The Influence of Palm Kernel Shell on the Mechanical Strength Properties of Reinforced Concrete Deep Beams

The Influence of Palm Kernel Shell on the Mechanical Strength Properties of Reinforced Concrete Deep Beams | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article The Influence of Palm Kernel Shell on the Mechanical Strength Properties of Reinforced Concrete Deep Beams Kwadwo Adinkrah-Appiah, Mark Adom-Asamoah, Russell Owusu Afrifa, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7376026/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 18 You are reading this latest preprint version Abstract This study investigates the influence of palm kernel shell (PKS) on the mechanical strength properties of reinforced concrete deep beams. A high strength lightweight concrete of grade 30 was prepared using palm kernel shell as coarse aggregate. Three pairs of deep beams, with and without shear reinforcement, of 150 mm width and 350 mm depth, having shear span-to-effective depth ratios of 1.0, 1.5 and 2.0, were prepared for the PKS reinforced concrete deep beams. The beams were cured for 7, 14, 21, and 28 days and tested for ductility and shear strength under three-point loading. The experimental results showed comparatively that the average ductility ratio of the PKS concrete deep beams without shear reinforcement was 1.6 times that of the normal weight concrete (NWC) whilst for the beams with vertical shear reinforcement, the ductility ratio was 1.3 times that of the NWC, showing superiority of palm kernel shell concrete (PKSC) over NWC in terms of ductility. Also, the normalized shear strength of the PKSC deep beams was found to be higher than the NWC samples at all a/d ratios. It was concluded that PKSC deep beams exhibit higher ductility and normalized shear strength characteristics than NWC deep beams and hence can be considered in high-rise buildings as transfer girders especially in earthquake-prone zones. Palm kernel shell Deep beams Ductility ratio Shear strength Normal concrete weight Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 1. Introduction Concrete is one of the most widely utilized construction materials across the globe, which has significantly increased its demand within the industry (Adinkrah-Appiah et al., 2016 ). This rise in demand has consequently led to higher consumption of coarse aggregates, a key component of concrete that functions primarily as an economic filler in construction. Over the years, natural rock types of igneous, metamorphic, and sedimentary origin—such as granite, basalt, flint, and limestone—have commonly been used as coarse aggregates for concrete production (Adinkrah-Appiah et al., 2025 ; Adinkrah-Appiah, 2018 ; Adinkrah-Appiah et al., 2015 ; BS 812, Part 1:1975). Their physical qualities, including hardness, inertness, particle shape and texture, gradation, moisture content, specific gravity, soundness, and bulk density, make them suitable for this purpose. This practice has been standard in both maintenance works in advanced economies and new construction projects in developing countries. However, heavy reliance on natural rock resources is creating environmental concerns (Obeng et al., 2025 ; Adinkrah-Appiah, 2006 ). Additionally, the continuous extraction of aggregates from ecological sites has made concrete relatively expensive. This is largely due to the high cost of transporting aggregates over long distances, coupled with regulatory restrictions imposed by environmental authorities on quarrying activities. These challenges highlight the need to explore alternative coarse aggregate materials to either replace or supplement natural sources. Numerous studies on waste products—such as coal ash, blast furnace slag, fiberglass, plastics, sludge pellets, ceramic waste, asphalt debris, metal scraps, waste clay pots, polypropylene, and recycled concrete—have reported promising results as substitutes for conventional aggregates (Abeka et al., 2025 ; Adinkrah-Appiah et al., 2025 ; Obeng et al., 2025 ; Nimo-Boakye et al., 2023 ; Adinkrah-Appiah, 2018 ; Adom-Asamoah et al., 2018 ; Adinkrah et al., 2018 ; Adinkrah-Appiah & Obour, 2017 ; Adinkrah-Appiah & Kpamma, 2013 ; Adinkrah-Appiah & Obour, 2012 ; Adinkrah-Appiah, 2006 ; Emmitt & Gorse, 2010 ; Moulinier et al., 2006 ). Some research has also investigated agricultural wastes as partial replacements for cement to improve performance and promote environmentally friendly construction (Assiamah et al., 2025 ; Assiamah et al., 2024 ; Assiamah et al., 2022 ). Many of these waste products fall under artificial lightweight aggregates (Teo et al., 2006 ), whose application in developed countries has contributed significantly to infrastructure development (Mahmud et al., 2009 ). Since the mechanical and physical properties of aggregates influence the strength, ductility, and durability of concrete, it is essential to assess the performance of these alternatives before widespread adoption. Palm Kernel Shell (PKS), a by-product of palm kernel oil extraction, has recently gained attention as a potential lightweight coarse aggregate in concrete production due to its favorable properties (Alengaram et al., 2008 ). Studies on PKS concrete (PKSC) reveal that it performs well in compression, shear, flexure, ductility, aggregate interlock, and bonding with steel reinforcement (Teo et al., 2006 ; Alengaram et al., 2008 ; Adinkrah-Appiah et al., 2015 ). PKSC beams, in particular, have demonstrated higher ductility than conventional normal-weight concrete (NWC) beams (Teo et al., 2009 ; Alengaram et al., 2011; Shafigh et al., 2011 ). For instance, Alengaram et al. ( 2008 ) observed that PKSC beams achieved a displacement ductility ratio of 1.7 compared to NWC beams. Teo et al. ( 2006 ) concluded that the promising results from PKS as a lightweight aggregate indicate its suitability for structural concrete, especially in affordable housing and in seismic zones, where its low weight and ductility are advantageous. Reinforced concrete (RC) beams are known to exhibit reduced shear strength as their depth increases, a phenomenon referred to as the size effect (Ghugal & Dahake, 2012 ; Appa Rao & Sundaresan, 2014 ). Nevertheless, shear strength generally improves as the shear span-to-depth ratio (a/d) decreases (Breña & Roy, 2009 ). Based on this, RC beams are classified as slender or deep beams (Adinkrah-Appiah & Adom-Asamoah, 2016 ). Regions where the shear span is less than twice the beam depth are termed disturbed regions (D-regions), where arch action dominates over beam action (ACI-318, 2008; Shuraiam, 2012). Deep beams, characterized by the presence of D-regions, tend to fail through brittle shear mechanisms (ACI-318, 2008; Appa Rao & Kunal, 2007 ). In high-rise buildings, deep beams often serve as transfer girders, where sufficient ductility is vital to resist various loads, including seismic forces. Given its lightweight nature and excellent ductility characteristics, PKSC emerges as a promising material for constructing RC deep beams in tall structures. This study, therefore, examines the shear strength and ductility performance of reinforced PKSC deep beams and compares them with equivalent NWC deep beams. 2. Experimental design 2.1 Materials PKS were collected from the waste left over by a local oil production mill in Sunyani Municipal, until an appreciable amount was obtained. The sand was obtained from Chiraa in Sunyani, and met the requirement specified by British Standard Institution (BS EN 12620:2002 + A1:2008). Machine crushed angular granite aggregate was used as coarse aggregate with sizes varying from 10mm to 19mm from a local source. The specific gravity of coarse aggregate was 2.68, the fineness modulus was 6.5 and the water absorption was 0.7 percent, which were all conducted in accordance with the physical property of coarse aggregate BS 812: Part 2: 1995 and BS EN 933-1:1997. After procurement, the sand was air dried to constant weight Ordinary Portland cement 42.5 R in the super rapid grade, a product by GHACEM Ltd in Ghana was used for the study. It also conforms to the specifications in British Standard (BS 12, 1996 ). The water used for this study was clean and did not contain any dangerous organic or chemical content. It was obtained from free-flowing tap. 2.2 Methods Shetty ( 2005 ) notes that the mix design for lightweight concrete is typically determined through trial batching. Following this approach, a grade 30 concrete, designated as PKSC30, was developed, cast, and tested for the reinforced PKS deep beams. The mix proportions adopted a sand-to-cement ratio of 1.8 and a PKS-to-cement ratio of 0.8, in line with the findings of Alengaram et al. ( 2008 ). For comparison, another concrete mix incorporating normal weight aggregate (granite) was prepared, labeled NWC30, with a target compressive strength of 30 MPa. The detailed mix proportions for both PKSC30 and NWC30 are presented in Table 1 . Table 1 Mix Proportions for Concrete Samples Concrete mix Design 28-day Target Cube Strength (N/mm 2 ) Cement Content (Kg/m 3 ) Water/ Cement Ratio (W/C) Sand/ Cement Ratio (S/C) Coarse Aggregate/ Cement Ratio (A/C) Super-Plasticizer (%) PKSC30 30 450 0.40 1.4 0.7 1.5 NWC30 30 350 0.50 2.0 4.0 0.5 A total of three beam pairs, comprising PKSC and NWC beams with and without shear reinforcement, were designed to fail primarily in shear. To prevent premature anchorage failure, adequate reinforcement anchorage was ensured by extending the reinforcement 150 mm beyond the support centerlines. Each beam was reinforced with 1.0% mild steel longitudinal reinforcement, having a yield strength of 413 MPa and an elongation capacity of 22%, and was cast in timber formwork. The principal experimental variables considered included the shear span-to-effective depth ratio (a/d = 1.0, 1.5, and 2.0), the Shear Reinforcement Index (SRI), and the concrete type. All beams had a rectangular cross-section measuring 150 mm in width and 350 mm in overall depth. The general notation adopted for beam identification followed the format C/A/I, where: C represents the concrete type, with P for PKSC and N for NWC, A denotes the a/d ratio, which could be 1.0, 1.5, or 2.0, and I signifies the shear reinforcement index (SRI), with W0 for SRI = 0.0% and V8 for SRI = 0.8%. The shear reinforcement index (SRI) was calculated using Eq. 1. Beam details are presented in Tables 2 and 3 , covering deep beams without shear reinforcement and those with vertical shear reinforcement, respectively, while Fig. 1 illustrates a PKSC deep beam specimen prepared for testing. \(\:SRI={A}_{s}{f}_{y}/{S}_{v}{b}_{v}\) % Eq. 1 Table 2 PKSC and NWC deep beams without shear reinforcement Beam ID Effective depth d (mm) Effective Span L (mm) Shear Span, a (mm) (a/d) 6mm shear reinforcement spacing (mm) P/1.0/W0 312 625 312.5 1.0 - - P/1.5/W0 312 940 470.0 1.5 - P/2.0/W0 312 1250 625.0 2.0 - N/1.0/W0 312 625 312.5 1.0 - N/1.5/W0 312 940 470.0 1.5 - N/2.0/W0 312 1250 625.0 2.0 - 3. Results and Discussions The results of the mechanical property tests on the coarse aggregates and the resulting concrete types were recorded and analyzed. Table 3: PKSC and NWC deep beams with vertical shear reinforcement Beam ID Effective depth d (mm) Effective Span L (mm) Shear Span, a (mm) (a/d) 6mm shear reinforcement spacing (mm) P/1.0/V8 312 625 312.5 1.0 80 P/1.5/V8 312 940 470.0 1.5 80 P/2.0/V8 312 1250 625.0 2.0 80 N/1.0/V8 312 625 312.5 1.0 80 N/1.5/V8 312 940 470.0 1.5 80 N/2.0/V8 312 1250 625.0 2.0 80 3.1 Mechanical Tests on Aggregates The laboratory characterization of coarse aggregates (Table 4) revealed notable differences between palm kernel shell (PKS) and granite aggregates. The PKS exhibited an Aggregate Impact Value (AIV) of 4.88%, while granite recorded 9.73%. For comparison, Teo et al. (2009) reported an AIV of 7.51% for PKS, suggesting that the PKS used in this study demonstrated superior resistance to impact loading. Although both aggregate types met the British Standard (BS 882, 1983) specification for maximum allowable AIV, the PKS value was approximately half of that for granite, indicating a higher relative toughness. Since resistance to sudden impact significantly affects the load-carrying capacity of concrete, these results suggest that PKS aggregate concrete could outperform granite-based concrete in impact-sensitive applications. Similarly, the Aggregate Crushing Value (ACV) tests showed that PKS recorded 2.33% compared to 17.95% for granite. Both values are within the BS 812 (1983) limit of 35%. However, the PKS result represents only about 13% of the granite value, reflecting a much higher resistance to crushing. This finding is consistent with observations by Teo et al. (2009), who reported an ACV of 8% for PKS, again highlighting that the PKS used in this investigation exhibits better crushing resistance. The reduced production of fines from PKS under load further corroborates its toughness. The relatively lower AIV and ACV values obtained for PKS compared to granite imply that PKS concrete is likely to exhibit improved ductility and energy absorption under compressive and impact loads, supporting earlier findings on the enhanced deformability of PKS-based lightweight concrete (Teo et al., 2009; Shafigh et al., 2011). Furthermore, abrasion resistance tests showed a value of 7.7% for PKS compared to 31.9% for granite, underscoring the higher wear resistance of PKS aggregates. Collectively, these results point to PKS as a promising coarse aggregate, capable of contributing to the development of lightweight concrete with superior ductility and durability characteristics. Table 4: Physical Characteristics of PKS and Granite Aggregates Properties PKS Granite Specifications Grain size (mm) 3 – 18 6.3 - 20 12.5 maximum for PKS (Teo et al 2006) Shell thickness, mm 1 – 3 - 0.5-3 (Teo et al 2006) Specific gravity 1.02 2.75 1.17 for PKS (Teo et al 2006) Bulk unit weight, kg/m 3 588.75 917.50 500-600 for PKS (Teo et al. 2006) Fineness Modulus 4.38 5.89 2-4 for fine aggregates and 4-6 for coarse aggregates 24-Hour Water Absorption, % 6.75 0.68 33 for PKS (Teo et al. 2006); ≤ 25 for normal weight (BS812: Part 107) Aggregate Impact Value, % 4.88 9.73 ≤ 25% (BS812: 1983) Aggregate Crushing Value, % 2.33 17.95 ≤ 35% (BS812:1983) Flakiness Index (%) 38.0 24.0 ≤ 45% (for < 20mm, BS812-105) Elongation Index 16.0 22.0 ≤ 45% (for < 20mm, BS812-105) Los Angeles Abrasion (%) 7.7 31.9 < 50 (BS812: 1983) 3.2 Tests on Hardened Concrete Samples The mechanical properties of PKSC and NWC are summarized in Table 5. The modulus of elasticity (E) of PKSC was measured at 12.28 GPa, compared with 28.5 GPa for NWC, indicating that the E-value of PKSC is approximately 43% of that of its normal-weight counterpart. This finding is consistent with established trends for lightweight concrete, where E-values typically range between 10–24 GPa (FIP Manual, 1983). The reduced stiffness of PKSC explains its susceptibility to larger deflections under load, a common drawback of lightweight concretes. Comparable results have been documented in previous studies. Alengaram et al. (2008) reported an E-value of 10 GPa for PKSC, which was about 33% of the corresponding NWC, while Shafigh et al. (2011) found values between 10.8 and 18.4 GPa for PKSC. The value obtained in the present study therefore aligns well with the reported range, strengthening the evidence that PKSC consistently develops lower elastic modulus relative to NWC, despite comparable compressive strengths. The relatively lower modulus of elasticity, combined with the previously demonstrated ductility advantages of PKSC (Teo et al., 2006; Alengaram et al., 2011), suggests that PKSC beams may undergo greater deformations but can dissipate energy more effectively than NWC beams. These mechanical property results support the proposition of PKSC as a suitable material for structural applications where ductility and lightweight characteristics are beneficial, such as in seismic regions and high-rise structures. Table 5: Modulus of Elasticity, Splitting Tensile Strength and Modulus of Rapture Values for Concrete Samples Type of Concrete Modulus of Elasticity (E-value) (GPa) Maximum Strain Splitting Tensile Strength (KPa) Modulus of Rupture (MoR) (MPa) PKSC30 12.28 0.0026 1.80 1.19 NWC30 28.5 0.0018 3.53 2.88 The compressive strength of the two types of concrete is recorded in Table 6. The 28-day compressive strength results were 33.70 and 42.93 MPa for the PKSC and the NWC samples respectively, showing a higher compressive strength for the NWC than the PKSC. The development of the compressive strength with time is shown in Figure 2, portraying negligible strength development at latter days for the PKSC compared to the NWC. Table 6: Cube Compressive Strength of Concrete Concrete Grade Cube Compressive Strength (MPa) 3 Days 7 Days 28 Days 90 Days PKSC30 21.92 27.12 33.70 33.96 NWC30 34.75 37.84 42.93 48.63 3.3 Shear Strength Characteristics of Deep Beam Samples The deep beam specimens without shear reinforcement predominantly failed by strut action through diagonal splitting , characterized by the rupture of the concrete struts between the loading and support points, accompanied by a loud explosive sound at failure. This mode of failure is typical of deep beams where the load is primarily transferred through compression struts rather than flexural action (Appa Rao & Kunal, 2007; ACI-318, 2008). Both PKSC and NWC specimens displayed this diagonal-splitting strut failure, indicating no fundamental difference in the failure mechanism between the two concrete types. In terms of crack propagation, flexural cracks first appeared at mid-span as the load was applied. With further loading, diagonal cracks developed, extending from the bottom corners of the support plates towards the load application points at the top of the beam. These crack patterns, observed in both PKSC and NWC beams, are consistent with the behaviour of deep beams reported in the literature, where flexural cracks precede shear-induced diagonal cracks (Ghugal & Dahake, 2012; Shuraim, 2012). Representative examples of the observed failure modes and crack distributions are presented in Figures 3a and 3b. The similarity in crack initiation and failure progression between PKSC and NWC beams suggests that PKSC can replicate the shear behaviour of conventional concrete in deep beam applications, while potentially offering additional ductility benefits as reported in earlier PKSC studies(Teo et al., 2006; Alengaram et al., 2011). In contrast to beams without shear reinforcement, specimens incorporating vertical stirrups exhibited a more ductile failure mode , characterized by a greater number of cracks with comparatively smaller widths prior to failure. PKSC beams developed a larger number of cracks overall and exhibited wider crack openings at ultimate load than the corresponding NWC beams, reflecting the influence of the lightweight aggregate on crack propagation and strain distribution. The crack development sequence began with the formation of multiple flexural cracks under initial loading, followed by the gradual emergence of diagonal strut cracks extending between the support and loading plates. These diagonal cracks widened progressively until failure occurred. Unlike the explosive failures observed in beams without shear reinforcement, the reinforced beams failed more silently, with the failure mechanism dominated by shear-compression crushing of the struts . Representative crack patterns are illustrated in Figures 4a and 4b. The load history further demonstrated that the shear strength of both PKSC and NWC beams increased as the shear span-to-depth ratio (a/d) decreased , consistent with arch action principles in deep beams (Ashour et al., 2003; Londhe, 2011). For example, the ultimate shear strength of PKSC beams without shear reinforcement increased from 142 kN (P/2.0/W0) to 190 kN (P/1.5/W0), and further to 226 kN (P/1.0/W0), as the a/d ratio decreased from 2.0 to 1.5 and then to 1.0, respectively (Table 4). These results represent a 34% strength increase when the ratio was reduced from 2.0 to 1.5 and a further 19% increase when reduced from 1.5 to 1.0. This trend highlights the critical role of the a/d ratio in governing the shear capacity of PKSC beams, mirroring behaviour long established for NWC beams (Ghugal & Dahake, 2012; Appa Rao & Sundaresan, 2014). The improved performance of PKSC beams at lower a/d ratios demonstrates their capacity to exploit strut-and-tie action effectively, while their higher ductility relative to NWC offers additional benefits for applications in seismic and high-rise structures. This significant response of the shear strength of PKSC deep beams to the a/d ratio confirms that the shear strength of a deep beam fundamentally depends on its a/d ratio, and that the a/d ratio is the overriding parameter that affects the shear strength of a deep beam, as has been found by other researchers (Ashour et al. 2003; Londhe, 2011). The corresponding NWC in the study also produced similar results. Comparison of the shear capacities of the PKSC and NWC deep beams is better achieved by normalizing the ultimate loads with the square-root of the corresponding 28-day cube compressive strength of the concrete. Table 7 shows that the PKSC deep beam samples produced higher normalized failure loads of 38.9, 32.7 and 24.5 MPa for a/d ratios of 1.0, 1.5 and 2.0 respectively, whilst for the NWC, the normalized failure loads were 34.2, 25.6 and 24.4 for a/d ratios of 1.0, 1.5 and 2.0 respectively for the beams without shear reinforcement. Similarly, for the beams with vertical shear reinforcement, the normalized loads were 39.9, 38.9 and 38.6 N/mm 2 , whilst the NWC deep beam samples produced 35.1, 34.8 and 34.2 N/mm 2 for the a/d of 1.0, 1.5 and 2.0 respectively. The results show that the PKSC deep beams exhibit higher normalized shear strength characteristics compared to the NWC deep beams. This confirms the result of Alengaram et al. (2011) which reported higher shear strength for PKSC slender beams compared to the control NWC beams. 3.4 Crack and Deflection Response of PKSC and NWC Deep Beams The cracking patterns of the tested beams, as summarized in Table 7, revealed consistent trends between PKSC and NWC specimens. With the exception of specimen N/1.5/W0, all beams first developed flexural cracks under increasing load, which were subsequently followed by the formation of diagonal strut cracks at higher load levels. For the PKSC deep beams without shear reinforcement, the first flexural cracks appeared at load levels between 41% and 54% of the ultimate load , while the corresponding NWC beams exhibited first flexural cracks between 40% and 67% of their ultimate load capacity . Similarly, in beams with vertical shear reinforcement, PKSC specimens showed initial flexural cracks between 26% and 53% of ultimate load, whereas the range for NWC specimens was 42% to 75% . Following the initiation of flexural cracks, strut (diagonal) cracks appeared and became the dominant cracking mode. These diagonal cracks propagated from the bottom support region towards the upper loading plates and increased both in width and length with continued loading, eventually governing the ultimate failure of the beams. For PKSC deep beams without shear reinforcement, first strut cracks appeared at 46%–60% of the ultimate load, while NWC beams showed a wider range of 46%–72% . With vertical shear reinforcement, first strut crack loads ranged between 41% and 70% for PKSC and between 53% and 91% for NWC. The ratio of both first flexural and strut crack loads to ultimate load was found to increase as the a/d ratio decreased for both concrete types, regardless of the presence of shear reinforcement. This trend is consistent with the enhanced arching action at lower shear span-to-depth ratios, which delays the initiation of diagonal cracking (Ashour et al., 2003; Londhe, 2011). A key distinction emerged between the two concrete types: at all a/d ratios, PKSC beams developed first flexural and strut cracks at lower percentages of ultimate load compared to NWC beams . This behaviour implies that PKSC beams undergo more progressive crack development and higher inelastic deformation prior to failure, while NWC beams display relatively brittle responses. At ultimate load, PKSC beams exhibited larger crack widths than NWC beams, further supporting their superior energy absorption capacity and ductility. This finding aligns with earlier observations on PKSC slender beams, where higher displacement ductility was recorded compared to normal-weight counterparts (Alengaram et al., 2008). Consequently, PKSC emerges as a promising material for deep beam applications, where brittle failure is a dominant concern (Appa Rao & Kunal, 2007). Table 7: Shear strength characteristics of deep beam samples Beam ID a/d f cu (MP) Load at first Crack (KN) Max. Crack Width (mm) Max. Mid-Span Deflection (mm) P max (KN) Nom-alized P max (N/mm 2 ) Failure Mode Flex-ural Strut P/1.0/W0 1.0 33.70 92 104 0.64 2.06 226 38.9 SF/DS P/1.5/W0 1.5 33.70 82 84 1.60 3.73 190 32.7 SF/DS P/2.0/W0 2.0 33.70 78 86 3.80 4.00 143 24.5 SF/DS P/1.0/V8 1.0 33.70 122 160 0.47 2.60 230 39.6 SF/SC P/1.5/V8 1.5 33.70 80 94 1.30 4.04 226 38.9 SF/SC P/2.0/V8 2.0 33.70 58 92 0.82 3.98 224 38.6 SF/SC N/1.0/W0 1.0 42.93 150 162 0.50 2.10 224 34.2 SF/DS N/1.5/W0 1.5 42.93 - 78 2.6 4.85 168 25.6 SF/DS N/2.0/W0 2.0 42.93 66 108 1.78 2.95 160 24.4 SF/DS N/1.0/V8 1.0 42.93 172 210 0.45 2.28 230 35.1 SF/SC N/1.5/V8 1.5 42.93 98 124 0.80 2.43 228 34.8 SF/SC N/2.0/V8 2.0 42.93 94 118 0.62 2.97 224 34.2 SF/SC SF=Strut failure, DS=Diagonal splitting, SC=Shear compression The deflection of the PKSC and NWC deep beams without shear reinforcement is as shown in Figures 5 and 6, whilst that for the beams with vertical shear reinforcement is portrayed in Figures 7 and 8. The load-deflection response of the PKSC deep beams with and without shear reinforcement shows that as the a/d ratio increased from 1.0 through 1.5 to 2.0, the stiffness of the beams reduced whilst the ultimate deflection at failure increased (Figures 5 and 7). This implies that, PKSC deep beams exhibit similar behaviour as reinforced NWC deep beams, as a decrease in a/d ratio results in an increase in the stiffness and hence the shear strength, as found for NWC (Ashour et al. 2003; Londhe, 2011). The NWC deep beams in the study showed similar trends as presented in Figures 6 and 8. However, in all cases the NWC deep beam samples exhibited higher resistance to deflection compared to the PKSC deep beams. This is portrayed by the relative steeper slopes of the NWC deep beam curves, for both beams with and without shear reinforcement, indicating that NWC deep beams have higher stiffness, and hence exhibit brittle failure, compared to corresponding PKSC deep beams. The PKSC deep beams experienced larger deflections in all cases at failure compared to the NWC deep beams. This confirms the findings of Alengaram et al. (2008) that PKSC slender beams exhibit higher deflections at failure and hence possess higher ductility characteristics at failure than similar NWC slender beams. 3.5 Ductility of PKSC and NWC deep beams Ductility, defined as the capacity of a structural element to absorb energy and undergo significant inelastic deformation, is a key property in reinforced concrete design because it permits stress redistribution and provides warning before ultimate failure occurs (Duthinh & Starnes, 2001; Adom-Asamoah & Afrifa, 2013). In structural concrete, ductility may be evaluated in terms of curvature, rotation, or displacement. This study employed the displacement ductility ratio (μ) , expressed as the ratio of ultimate deflection to the deflection at which the flexural reinforcement yields. A higher ductility ratio indicates a greater capacity of the member to sustain deformation before collapse. Ratios between 3 and 5 are generally regarded as adequate for structural members, as they signify the ability to accommodate large displacements under dynamic actions such as earthquakes (Teo et al., 2006). In this investigation, the yield points of the flexural steel were identified from the load–deflection curves, specifically at the second stage where a noticeable change in slope occurs, following the procedure recommended by Adom-Asamoah and Afrifa (2013). Analysis of the displacement ductility ratios presented in Tables 8 and 9 revealed that PKSC deep beams without shear reinforcement consistently exhibited higher ductility values compared to corresponding NWC beams across all a/d ratios . A similar observation was made for beams with vertical shear reinforcement (Tables 10 and 11), where PKSC specimens again demonstrated superior ductility performance. The enhanced ductility of PKSC beams may be attributed to the lightweight aggregate’s influence on crack distribution and post-yield behaviour, which promotes progressive deformation rather than abrupt failure. In general, ductility in RC beams is influenced by several factors including longitudinal reinforcement, web reinforcement, shear span-to-depth ratio, and compressive strength of the concrete (Appa Rao & Injaganeri, 2013). For a given reinforcement configuration, an increase in concrete compressive strength is associated with improved ductility (Lin & Lee, 2003). The higher ductility indices obtained for PKSC in this study reinforce earlier findings on the superior deformability of lightweight aggregate concretes (Teo et al., 2006; Alengaram et al., 2011). These results underscore the potential of PKSC as a suitable material for applications requiring high energy absorption and inelastic deformation capacity, such as in seismic regions and critical load-bearing components in high-rise construction. Table 8: Displacement Ductility Ratio (μ) of PKSC deep Beams without Shear Reinforcement Beam ID a/d Ratio Ultimate Deflection (mm) Deflection at Yield (mm) Ductility Ratio (µ) P/1.0/W0 1.0 2.06 0.89 2.32 P/1.5/W0 1.5 3.73 1.09 3.42 P/2.0/W0 2.0 4 0.94 4.26 AVERAGE 3.33 STDEV 0.97 CV 0.29 Intrinsic factors that contribute to good ductility behaviour of a concrete are toughness and good shock absorbing capacity of the aggregates used to form the concrete (Teo et al, 2006; Adom-Asamoah and Afrifa, 2013). This is measured by the low aggregate crushing value (ACV) and aggregate impact value (AIV) of the PKSC aggregate. For instance, BS812: 1983 code specifies maximum ACV and AIV values of 35% and 25% respectively for good and sound concrete aggregates. The ACV and AIV obtained for the PKS aggregate were 2.33% and 4.88% respectively, whilst for the granite aggregate used for the NWC, the values were 17.95% and 9.73% (Table 4). Although all the two aggregates satisfy the BS812: 1983 requirements for both ACV and AIV, the PKS aggregate exhibited relatively lower values for both parameters and hence confirms the higher ductility performance characteristics of the PKSC deep beams compared to the NWC deep beam samples in the study. Table 9: Displacement Ductility Ratio (μ) of NWC deep Beams without Shear Reinforcement Beam ID a/d Ratio Ultimate Deflection (mm) Deflection at Yield (mm) Ductility Ratio (µ) N/1.0/W0 1.0 2.1 1.71 1.22 N/1.5/W0 1.5 4.85 1.61 3.01 N/2.0/W0 2.0 2.95 1.45 2.03 AVERAGE 2.09 STDEV 0.90 CV 0.43 Table 10: Displacement Ductility Ratio (μ) of PKSC deep Beams with Vertical Shear Reinforcement Beam ID a/d Ratio Ultimate Deflection (mm) Deflection at Yield (mm) Ductility Ratio (µ) P/1.0/V8 1.0 2.6 1.03 2.52 P/1.5/V8 1.5 4.04 0.83 4.87 P/2.0/V8 2.0 3.98 0.96 4.15 AVERAGE 3.85 STD 1.20 CV 0.31 Table 11: Displacement Ductility Ratio (μ) of NWC deep Beams with Vertical Shear Reinforcement Beam ID a/d Ratio Ultimate Deflection Deflection at Yield Ductility Ratio (µ) N/1.0/V8 1.0 2.28 0.78 2.92 N/1.5/V8 1.5 2.43 1.19 2.04 N/2.0/V8 2.0 2.97 0.71 4.18 AVERAGE 3.05 STD 1.08 CV 0.35 The experimental results demonstrated clear differences in ductility between PKSC and NWC deep beams. For specimens without shear reinforcement , the average displacement ductility ratios (μ) were 3.3 for PKSC and 2.1 for NWC , yielding a relative ductility factor of 1.6 in favour of PKSC. When vertical shear reinforcement was introduced, the average ductility ratios increased to 3.9 for PKSC and 3.1 for NWC , corresponding to a relative ductility of 1.3 . These findings indicate that while the addition of shear reinforcement enhanced the ductility of both concrete types, the improvement was more pronounced in NWC beams. This suggests that PKSC inherently possesses superior ductility characteristics, whereas NWC requires reinforcement to achieve comparable levels of inelastic deformation. Similar conclusions have been reported by Appa Rao and Injaganeri (2013), who identified web reinforcement as a key factor in improving ductility behaviour in RC beams. The implication of this result is that PKSC deep beams may require less web reinforcement than NWC beams to achieve satisfactory ductility , potentially leading to cost savings in reinforcement requirements. The intrinsic ductility of PKSC thus reduces dependence on shear reinforcement for crack control and energy dissipation. These findings are consistent with earlier work on slender beams. Alengaram et al. (2008) reported displacement ductility ratios of 4.8 for PKSC and 2.8 for NWC beams with shear reinforcement, corresponding to a relative ductility of 1.7 . Although absolute ductility values are lower in deep beams due to their inherently brittle behaviour (Appa Rao & Kunal, 2007), the relative ductility advantages of PKSC observed in this study (1.3–1.6) align closely with the slender beam results. The structural significance of these results lies in the application of PKSC in deep beam design for high-rise structures , particularly as transfer girders. Deep beams are typically associated with brittle shear-compression failures; thus, the higher ductility of PKSC can enhance post-cracking performance and provide critical energy absorption capacity. Moreover, the lightweight nature of PKSC offers an added advantage for seismic design, where reduced self-weight decreases inertial forces. The combination of high ductility and low density makes PKSC a promising material for RC deep beams in earthquake-prone regions, while its enhanced energy absorption also contributes to the higher relative shear strength observed in PKSC beams compared to NWC beams. 4. Conclusions Based on the results obtained, the following conclusions were drawn on the use of PKSC for the design of reinforced concrete deep beams: PKS aggregate possesses lower aggregate crushing, aggregate impact and higher abrasion resistance than normal weight aggregate which makes it a material that produces concrete that absorbs shocks and wearing better than normal weight aggregate concrete. Strength development of PKSC is at early age compared to NWC samples. After 28 days, PKSC does not develop any appreciable strength. PKSC develops almost its utmost strength around 7 days. PKSC deep beam samples having a/d of 2.0 and below fail by strut failure through diagonal-splitting with a loud explosion for beams without shear reinforcement; whilst for beams with vertical shear reinforcement, a more ductile failure mode occurs through shear compression without explosion. The shear strength of PKSC deep beams increase as a/d ratio reduces, as has been found for normal weight concrete deep beams. The normalized shear strength of PKSC deep beams is higher than corresponding NWC deep beams at different a/d ratios. First flexural and strut cracks appear at lower percentages of ultimate loads in PKSC deep beams with and without shear reinforcement than in NWC deep beams. This shows that PKSC deep beams exhibit higher inelastic deformations, and hence exhibit higher ductility characteristics at failure. Average displacement ductility ratio of 3.3 and 2.1 were recorded for PKSC and NWC deep beams without shear reinforcement respectively; whilst for beams with vertical shear reinforcement the average displacement ductility ratios were 3.9 and 3.1 for PKSC and NWC deep beams respectively. This gives a relative displacement ductility ratio of 1.6 and 1.3 existing between PKSC and NWC deep beams without shear reinforcement and with vertical shear reinforcement respectively. This further shows that, the high relative ductility of PKSC deep beams over NWC deep beams reduces as shear reinforcement is introduced as a result of the more brittle NWC improving its ductility at a relatively higher rate with the introduction of shear reinforcement. Declarations Ethics approval and consent to participate Not applicable. Consent for publication The authors guarantee that this manuscript is not published or not under consideration by any other journal and that the manuscript is original and is their own work. Availability of data and material The datasets used and/or analysed during the current study are available from the corresponding author upon reasonable request Competing interest The authors declare that they have no competing financial interests or personal relationships that may have influenced the work reported in this study Funding The authors received no funding for this research Authors’ contributions All the authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by KA, MA, ROA . The first draft of the manuscript was written by SA, and JO. All the authors commented on previous versions of the manuscript. All the authors have read and approved the final manuscript Acknowledgements We thank the anonymous reviewers for their valuable comments and suggestions, which helped improve the quality of this work Authors' information Kwadwo Adinkrah-Appiah is an Associate Professor of Civil Engineering. He has authored several research publications. His research areas include shear strength of reinforced palm kernel shell concrete deep beams, vulnerability of building structures in the seismic zones of Ghana, the use of waste materials as aggregates for concrete and building block production for sustainable construction, the use of lateritic soils for concrete and building block production, lean construction in the Ghanaian construction industry and the economic cost of road accidents in Ghana. Mark Adom-Asamoah is the Provost of the College of Engineering at the Kwame Nkrumah University of Science and Technology, Kumasi. He is a past Dean of the Faculty of Civil and Geo-Engineering and Head of the Department of Petroleum Engineering. He is a Fulbright Senior Research Fellow, Commonwealth Scholar and British Council Scholar. He was a visiting scholar at the University of Bristol, UK and Arizona State University, USA. His research interests are behavior of local civil engineering materials and seismic behavior of low-medium seismic regions. Russell O. Afrifa is a lecturer in the Civil Engineering Department at Kwame Nkrumah University of Science and Technology (KNUST) and specializes in structural engineering, reinforced concrete design, and structural materials. With a PhD in Civil Engineering and over 15 years of experience as a structural Engineer, Dr. Afrifa brings a wealth of practical knowledge to his academic role. His expertise extends to the design and analysis of reinforced concrete structures, as well as the study of advanced structural materials. Dr. Afrifa's research aims to increase the safety, durability, and efficiency of infrastructure through innovative engineering solutions Sampson Assiamah is a lecturer from the Department of Building and Technology, Sunyani Technical University, and is currently pursuing PhD in structural engineering at Kwame Nkrumah University of Science and Technology (KNUST), Department of Civil Engineering. My research interests are related to sustainable construction materials and processing, structural engineering, materials science, construction technology and building science. J acqueline Obeng is a lecture from the Department of Civil Engineering, Sunyani Technical University, and is currently holds PhD in structural engineering at KNUST, Department of Civil Engineering. My research interests are related to sustainable construction materials and processing, structural engineering, materials science, construction technology and building science. References ACI 318 (2008). “ACI Committee 318 (2008). Building Code Requirements for Structural Concrete (ACI 318-08) and Commentary”. American Concrete Institute, Farmington Hills, MI. Abeka, H. Obeng, J. Sasa, J. Adinkrah-Appiah, K. Obeng-Ankamah, N. Abdulai, M. Koogyah, E. and Okyere, C. (2025). “Assessing the Resilience of Palm-Kernel–Based Concrete to Sodium Chloride and Sulphuric Acid Attack”. Journal of Engineering Research and Reports 27 (5):399-410. https://doi.org/10.9734/jerr/2025/v27i51514. Adinkrah-Appiah, K., Assiamah, S. & Agyeman, S. Effect of partial replacement of sawdust with sand on the properties of sandcrete blocks for sustainable non-load bearing walls in Ghana. Discov Civ Eng 2 , 95 (2025). https://doi.org/10.1007/s44290-025-00246-4 Adinkrah-Appiah, K. (2018). Non-conventional coarse aggregate concrete for sustainable housing construction in Ghana. Sunyani Technical University International Journal of Technology (STUIJT). Vol 1, Issue 5 - May, 2018, (ISSN 2508–0997, Online). Adinkrah, K. A., Asamoah, M. A., & Osei, J. B. (2018). Structural Lightweight PKS Concrete without the use of Supplementary Cementing Materials. Journal of Structural Technology , 3 (2), 1-15. Adinkrah-Appiah K, Kpamma EZ, Nimo-Boakye A, Asumadu KT, Obeng-Ankamah N. Annual consumption of crushed stone aggregates in Ghana. J Civil Eng Archit Res. 2016;3(10):1729–37. Adinkrah-Appiah, K. and Adom-Asamoah, M. (2016). Characterization and Shear Strength Prediction of Reinforced Concrete Deep Beams – A Review. International Journal of Science and Research (IJSR). ISSN (Online): 2319-7064, Index Copernicus Value (2013): 6.14, Impact Factor (2013): 4.438 Adinkrah-Appiah, K. & Obour, G. D. Fused laterite powder substitution for cement in concrete production. Int Conf Appl Sci Technol Conf Proc. 2017;3(1):100–5. Adinkrah-Appiah, K. Kpamma, E. Z. Nimo-Boakye, A. Asumadu, K. T. Obeng-Ankamah, N. (2016). Annual consumption of crushed stone aggregates in Ghana. J Civil Eng Archit Res. 2016;3(10):1729–37. Adinkrah-Appiah, K. (2016). Shear Strength of Reinforced Palm Kernel Shell Concrete Deep Beams. ‎ LAP LAMBERT Academic Publishing. 1 October 2016b. ISBN-10 3659834459; ISBN-13: ‏ .978-3659834455 Adinkrah-Appiah, K. Obeng-Ankamah, H. and Abeka, H. K. (2016). Concrete pavement slabs reinforced with steel fibres from discarded vehicle tyres. STU International Journal of Technology (STUIJT) Vol. 1, Issue 1 -April, 2016 (ISSBN: 2508-0997, Online). www.stu.edu.gh. Adinkrah-Appiah, K. Adom-Asamoah, M. and Afrifa, R. O. (2015). Shear Strength Prediction of Palm Kernel Shell RC Deep Beams without Shear Reinforcement. 1st International Conference on Engineering, Science, Technology & Entrepreneurship, 2015. Department of Civil Engineering, K.N.U.S.T. Kumasi. 2015; 472–492. Adinkrah-Appiah, K. Adom-Asamoah, M. and Afrifa, R. O. (2015). “Reducing Environmental Degradation from Construction Activities: The Use of Recycled Aggregates for Construction in Ghana”. Journal of Civil Engineering and Architecture Research. Vol. 2, No. 8, 2015, pp. 831-841. Adinkrah-Appiah, K. and Kpamma, E. Z. (2013). Improving the Structural Characteristics of Earth Blocks as an Input of Affordable Housing for Low Income Northern Communities of Ghana. International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2013): 6.14 | Impact Factor (2013): 4.438. Adinkrah-Appiah, K. Obour, D. G. The potential of rice husk ash as a partial replacement for Cement in concrete production in Ghana. 1st International Conference on Infrastructure Development in Africa (ICIDA) Conference Proceedings 2012. Department of Building Technology, K.N.U.S.T., Kumasi. 2012. Adinkrah-Appiah, K. (2006). Salancrete Building Blocks From Mixture of sand, Laterite And Cement For Sustainable housing In Ghana. Sunyani Polytechnic Lecture Series V, Sunyani, Ghana, volume 4, number 1, June 2006. ISBN 0855–0843. 2021; 157–175. Adom-Asamoah, M. Banahene J. O. Adinkrah-Appiah, K. (2018). Structural Characteristics of Reinforced Palm Kernel Shell Concrete Deep Beams. Civil Engineering Journal Vol. 4, No. 7, July, 2018. Available online at www.CivileJournal.org. Adom-Asamoah, M. and Afrifa R. O. (2013). Performance evaluation of shear strength of reinforced concrete beams made from phyllite aggregates. A Thesis submitted to the Department of Civil Engineering, KNUST, Kumasi, in partial fulfillment of the requirement for the degree of Doctor of Philosophy. Department of Civil Engineering, College of Engineering. Alengaram, U. J. Jumaat M. Z. and Mahmud, H. (2008). “Ductility behaviour of reinforced palm kernel shell concrete beams”. Eur. J. Scient. Res. 23 (3):406-420. Appa Rao, G. and Sundaresan, R. (2014), “Size Dependent Shear Strength Of Reinforced Concrete Deep Beams Based On Refined Strut-And-Tie Model”. Journal of Frontiers in Construction Engineering. Mar. 2014, Vol. 3 Iss. 1, PP. 9-19. Appa Rao, G. and Injaganeri, S. S. (2013), “Minimum shear reinforcement for optimum ductility of reinforced concrete beams”. International Journal of Research in Engineering and Technology. eISSN: 2319-1163, pISSN: 2321-7308. Vol. 2 Issue 10, Oct-2013. Appa Rao G. and Kunal K. (2007). “Shear strength of Reinforced Concrete deep beams”. FraMOS- 6 , 17-22, June, 2007, Catania, Italy, pp. 671-675. Ashour, A. F., Alvarez, L. F., and Toropov, V. V. (2003). "Empirical modeling of shear strength of RC deep beams by genetic programming." Computers and Structures, 81 (5), 331-338. Assiamah, S. Kankam, C. K. Adinkrah-Appiah, K. et al. (2025). The impact of burnt sawdust ash from timber species as partial cement replacements on the durability properties for sustainable interlocking blocks. Discov Civ Eng. 2025;2:20. https://doi.org/10.1007/s44290-025-00183-2. Assiamah, S. Kankam, C. K. Adinkrah-Appiah, K. Afrifa, R. O. and Twumasi, J. O. (2024). Effects of burnt sawdust ashes from timber species on the strength properties of laterite-interlocking blocks. Discov Civil Eng. 2024;1(1):87. Assiamah, S. Kankam, C. K. Afrifa, R. O. Adinkrah-Appiah, K. Banahehe, O. J. (2024). Improving tensile strength characteristics and water absorption of laterite interlocking blocks enhanced with different burnt sawdust ash from timber species. J Mater Sci Res Rev. 2024a;7(4):532–50. Assiamah, S. Kankam, C. K. Adinkrah-Appiah, K. Afrifa, R. O. and Twumasi, J. O. (2024b). Effects of burnt sawdust ashes from timber species on the strength properties of laterite-interlocking blocks. Discov Civil Eng. 2024;1(1):87. Assiamah, S. Kankam, C. K. Adinkrah-Appiah, K. Afrifa, R. O. Jack, Banahene O. J. and Okai, D. (2024c). Influence of burnt sawdust ash from timber species on the chemical strength properties of laterite-interlocking blocks. J Mater Sci Res Rev. 2024c;7(2):252–61. Assiamah, S. Agyeman, S. Adinkrah-Appiah, K. and Danso, H. (2022). Utilization of sawdust ash as cement replacement for landcrete interlocking blocks production and mortarless construction. Case Stud Constr Mater. 2022. https://doi.org/10.1016/j.cscm.2022.e00945. Breña S. F. and Roy N. C. (2009). “Evaluation of Load Transfer and Strut Strength of Deep Beams with Short Longitudinal Bar Anchorages”. ACI Structural Journal, V. 106, No. 5 Title no. 106-S63, MS No. S-2008-205. BS812 (1975). “Specification of Aggregates for Concrete”. British Standard Institute Part 1. BS882 (1983): “Specification of Aggregates for Concrete”, British Standard Institute. BS 12. (1996). Specification for Portland cement. British Standards Institution. BS EN 933-1:1997Testing for geometrical properties of aggregate. Determination of particle size distribution. Sieving method (AMD 15907). British Standard EN 12620: (2002). +A1: (2008). Aggregates for concrete masonry units. Duthinh, D. and Starnes, M. (2001). Strength and Ductility of Concrete Beams Reinforced with Carbon FRP and Steel. U.S. Department of Commerce, Technology Administration. Building and Fire Research Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899. Emmitt S. and Gorse C. (2010), “Introduction to Construction of Buildings. Second Edition”. Wiley-Blackwell. ISBN-10:1405 188545. FIP Manual, (1983). “FIP Manual of Lightweight Aggregate Concrete”, 2 ed. London: Surrey University Press. Ghugal Y. M. and Dahake A. G. (2012), “Flexural analysis of deep beam subjected to parabolic load using refined shear deformation theory”. Applied and Computational Mechanics, Vol 6 , (2012), 163–172. Lin and Lee, (2003), “Shear Behaviour of High Workability Concrete Beams”, ACI Structural Journal, Vol. 100 , No.5, Sept.-Oct. 2003, pp. 599-608. Londhe, R. S. (2011), "Shear strength analysis and prediction of reinforced concrete transfer beams in high-rise buildings." Structructural Engineering Mechanics, Vol. 37 (1), 39-59. MacGenley and Choo, 1990; McGenley, T. J. and Choo, B. S. (1990). Reinforced concrete: Design theory and examples. Second Edition. London; New York: E&FN Spon. Mahmud, H.B. Majuar, E. Zain, M.F.M. and Hamid, N.B.A.A. (2009). Mechanical Properties and Durability of High Strength Concrete Containing Rice Husk Ash. Journal of advanced concrete technology. Vol. 79 (1): 21-30. Moulinier, F. Lane, S. and Dunster, A. (2006), “The use of glass as aggregate in in Portland cement concrete”. The Waste and Resources Action Programme (WRAP), Banbury, Oxon. Nimo-Boakye, A., Nana-Addy, E., Adinkrah-Appiah, K. (2023). Burnt Clay Grinding Pot Waste Powder as a Partial Replacement of Ordinary Portland Cement for Concrete Production. In: Aigbavboa, C., et al. Sustainable Education and Development – Sustainable Industrialization and Innovation. ARCA 2022. Springer, Cham. https://doi.org/10.1007/978-3-031-25998-2_73 Obeng, J., Sasah, J., Adinkrah-Appiah, K. et al. (2025). A comprehensive review of local sustainable materials utilized in concrete production in Ghana. Discov Sustain 6 , 400 (2025). https://doi.org/10.1007/s43621-025-00898-3. Rogowsky, D. M., MacGregor, J. G. and Ong, S. Y. (1983), “Tests of Reinforced Concrete Deep Beams”. University of Alberta, Edmonton. Report number: 109. Shafigh, P. Jumaat, M. Z. Mahmud, H. and Alengaram, U.J. (2011). “A new method of producing high strength oil palm shell lightweight concrete”. Mater Des 2011; 32(10):4839–43. Shetty, M. S. (2005), “Concrete technology theory and practice”. 3rd Multicolor illustrative revised ed., India; 2005. Shuraim, A. B. (2012), “Behavior and shear design provisions of reinforced concrete D-region beams”. Journal of King Saud University – Engineering Sciences (2013) 25 , 65–74. Teo, D.C.L. Mannan M. A. Kurian V. J., and Zakaria I. (2006). Flexural behaviour of reinforced lightweight OPS concrete beams. In: 9th International conference on concrete engineering and technology, Malaysia; 2006. p. 244–252. Teo, D.C.L. Mannan M. A., Kurian V. J. (2009). Production of lightweight concrete using oil palm shell (OPS) aggregates. In: 4th International conference on construction materials: performance, innovations and structural implications, Nagoya, Japan; 2009. p. 661–6. Yang, K.H., Chung, S.H. and Ashour, A.F. (2007). “Influence of section depth on the structural behaviour of reinforced concrete continuous deep beams”, Mag. Concrete Res., 59(8), 575-586. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 27 Oct, 2025 Reviews received at journal 21 Oct, 2025 Reviews received at journal 19 Oct, 2025 Reviews received at journal 18 Oct, 2025 Reviews received at journal 16 Oct, 2025 Reviewers agreed at journal 12 Oct, 2025 Reviewers agreed at journal 12 Oct, 2025 Reviews received at journal 11 Oct, 2025 Reviewers agreed at journal 10 Oct, 2025 Reviews received at journal 08 Oct, 2025 Reviewers agreed at journal 07 Oct, 2025 Reviewers agreed at journal 07 Oct, 2025 Reviewers agreed at journal 07 Oct, 2025 Reviewers invited by journal 07 Oct, 2025 Editor invited by journal 28 Sep, 2025 Editor assigned by journal 24 Sep, 2025 Submission checks completed at journal 15 Sep, 2025 First submitted to journal 15 Sep, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7376026","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":531915857,"identity":"668917da-76a1-4800-97cf-ac76b86785e1","order_by":0,"name":"Kwadwo Adinkrah-Appiah","email":"","orcid":"","institution":"Sunyani Technical University","correspondingAuthor":false,"prefix":"","firstName":"Kwadwo","middleName":"","lastName":"Adinkrah-Appiah","suffix":""},{"id":531915861,"identity":"86078c22-db7d-46de-a19c-143a91842ccf","order_by":1,"name":"Mark Adom-Asamoah","email":"","orcid":"","institution":"Kwame Nkrumah University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Mark","middleName":"","lastName":"Adom-Asamoah","suffix":""},{"id":531915862,"identity":"a64149b6-444d-4718-9bbb-5a66587bdfb4","order_by":2,"name":"Russell Owusu Afrifa","email":"","orcid":"","institution":"Kwame Nkrumah University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Russell","middleName":"Owusu","lastName":"Afrifa","suffix":""},{"id":531915863,"identity":"07e2c5b0-3d4f-44c5-b51c-a8c734744b22","order_by":3,"name":"Sampson Assiamah","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABFElEQVRIiWNgGAWjYHADxgYgccCOH8ROKCBBS7IkiEowIN6qA4wbDoBoPFrk20+nPfxRcUdevv9w46cbNXeYjc+vTvzwwIBBnl/sAFYtBmdytxvznHlmuOFGYrN0zrFnfGY33m6WADrMcObsBOxaGHK3STO2HWbcIMHYIJ3DdpjZ7MbZDSAtCQa3sWuR73+7TfJn22H7+f0Hm3/n/DvMuHnG2c0/8GlhuJG7TYK37XBiw4HENulckHX8vdvw2mJw4y3IL4eTgX5ps87tO5wscYN3m0WCgQROv8j3524Dhthh2/n9xx/fzvl22I6//+zmmz8qbOT5pXE4jIGBDY0vAVYpgUs5Ni38B/CpHgWjYBSMghEIAITcbAESNE1JAAAAAElFTkSuQmCC","orcid":"","institution":"Sunyani Technical University","correspondingAuthor":true,"prefix":"","firstName":"Sampson","middleName":"","lastName":"Assiamah","suffix":""},{"id":531915865,"identity":"03f66103-ec52-494f-9b02-9860314ada43","order_by":4,"name":"Jacqueline Obeng","email":"","orcid":"","institution":"Sunyani Technical University","correspondingAuthor":false,"prefix":"","firstName":"Jacqueline","middleName":"","lastName":"Obeng","suffix":""}],"badges":[],"createdAt":"2025-08-14 17:23:23","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7376026/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7376026/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":93961991,"identity":"d9fe4973-517d-4f51-a47e-aa678c443b1d","added_by":"auto","created_at":"2025-10-20 17:15:15","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1761453,"visible":true,"origin":"","legend":"","description":"","filename":"PKSCDuctilityPaperFinalProf.docx","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/5efa67bb1366070ddcdd4231.docx"},{"id":93961988,"identity":"589ae9c3-c3fc-430a-8973-2515f83cb126","added_by":"auto","created_at":"2025-10-20 17:15:15","extension":"json","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":6634,"visible":true,"origin":"","legend":"","description":"","filename":"6d31d99a863848c4941dc4388242a758.json","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/25ee1c35a64b3395d54821f5.json"},{"id":93961983,"identity":"741c0fb6-d1ba-463c-8db1-486cf18e33d5","added_by":"auto","created_at":"2025-10-20 17:15:13","extension":"xml","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":154556,"visible":true,"origin":"","legend":"","description":"","filename":"6d31d99a863848c4941dc4388242a7581enriched.xml","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/bedb097bdf3718cd44feb5f5.xml"},{"id":93961916,"identity":"b564a4e6-136d-4f2f-bedb-86ebc6a5f61b","added_by":"auto","created_at":"2025-10-20 17:15:11","extension":"jpeg","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1074,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/68761a72c7f7b7390305d88d.jpeg"},{"id":93962325,"identity":"dd826277-b14b-4c97-959b-c80d639e4691","added_by":"auto","created_at":"2025-10-20 17:23:16","extension":"jpeg","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":77420,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/86633dd6ffe838d4f9a75b86.jpeg"},{"id":93961935,"identity":"7ecac23f-4672-4538-b8da-fbee29bece93","added_by":"auto","created_at":"2025-10-20 17:15:13","extension":"jpeg","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":112164,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/ca76c1edf8122c61f6e3ff95.jpeg"},{"id":93961985,"identity":"1b0eab33-cd50-443f-8248-979f15bdbc8c","added_by":"auto","created_at":"2025-10-20 17:15:13","extension":"jpeg","order_by":12,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":332767,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/6e9cd56371a7b6f6de2da69d.jpeg"},{"id":93961986,"identity":"60ad979b-c5f0-4e03-adfd-d592170cfe5a","added_by":"auto","created_at":"2025-10-20 17:15:14","extension":"jpeg","order_by":13,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":77466,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage5.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/8d39f3e85e2137c604011f76.jpeg"},{"id":93962313,"identity":"b4850f71-822b-441b-b5bd-d9dcc099513d","added_by":"auto","created_at":"2025-10-20 17:23:13","extension":"png","order_by":14,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":935,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/9e828067ba5fd3c1cd52de0a.png"},{"id":93961912,"identity":"ecadacea-463e-44e7-8fc6-32d6f1a1cb54","added_by":"auto","created_at":"2025-10-20 17:15:11","extension":"png","order_by":15,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":83201,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/a528a3dd1e108ace83f11233.png"},{"id":93961931,"identity":"3124670e-505b-4cde-b836-c06e801a0c53","added_by":"auto","created_at":"2025-10-20 17:15:12","extension":"png","order_by":16,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":75990,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/d9581a619ee2a61477600148.png"},{"id":93961992,"identity":"765f82de-e696-4767-80ef-2248a40e6a9c","added_by":"auto","created_at":"2025-10-20 17:15:16","extension":"png","order_by":17,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":94923,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/ae270acddb90815646766b78.png"},{"id":93961952,"identity":"35e6a9ca-b02e-4c90-9d87-42ce40fe7c3c","added_by":"auto","created_at":"2025-10-20 17:15:13","extension":"png","order_by":18,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":52900,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/9853025099c43218c7cddb89.png"},{"id":93961930,"identity":"9098912a-7640-4a55-b0aa-4ea0b0339c0f","added_by":"auto","created_at":"2025-10-20 17:15:12","extension":"xml","order_by":19,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":151881,"visible":true,"origin":"","legend":"","description":"","filename":"6d31d99a863848c4941dc4388242a7581structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/5b692f1debd597c91bbbddb0.xml"},{"id":93961987,"identity":"73ee27ed-bf44-4f3b-a38f-8092cb75df97","added_by":"auto","created_at":"2025-10-20 17:15:14","extension":"html","order_by":20,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":163054,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/cf8ac779f81644bdefdf5d67.html"},{"id":93961915,"identity":"661baa4a-ecd0-4dc4-aef5-b5de9fdbc16f","added_by":"auto","created_at":"2025-10-20 17:15:11","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":5713,"visible":true,"origin":"","legend":"\u003cp\u003eA PKSC deep beam specimen prepared for testing.\u003c/p\u003e","description":"","filename":"placeholderimage.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/543b733b8480081c197d5cb9.png"},{"id":93961989,"identity":"19444cf6-91bb-41ed-916a-d364213167ee","added_by":"auto","created_at":"2025-10-20 17:15:15","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":32610,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDevelopment of compressive strength of concrete samples\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/ca50190d8b4e257782a80a40.png"},{"id":93961927,"identity":"249e5b3d-e0f1-443e-b834-0142af252355","added_by":"auto","created_at":"2025-10-20 17:15:12","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1288224,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea: PKSC deep beam without shear reinforcement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eb: NWC deep beam without shear reinforcement\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/3bd92f8bc97e426c96c5d6d6.png"},{"id":93961933,"identity":"e8ae7cae-0ace-493d-a5c5-5c286ec035a5","added_by":"auto","created_at":"2025-10-20 17:15:13","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":1062404,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea: PKSC deep beam with vertical shear reinforcement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eb: NWC deep beam with vertical shear reinforcement\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/9d807745b2bb70085b595cae.png"},{"id":93961934,"identity":"72692b6a-8bfa-472b-990f-c9f4294454c6","added_by":"auto","created_at":"2025-10-20 17:15:13","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":31428,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eLoad-deflection curve for PKSC deep beams without shear reinforcement\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/7d813ec4917d6281f7a6a211.png"},{"id":93961932,"identity":"0d8ea538-5755-4b2e-8a3c-86da32aba613","added_by":"auto","created_at":"2025-10-20 17:15:13","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":27282,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eLoad-deflection curve for NWC deep beams without shear reinforcement\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/95bd94064e1a1a4d38fca1e1.png"},{"id":93961993,"identity":"41f76904-2240-413d-9945-12adda38861e","added_by":"auto","created_at":"2025-10-20 17:15:16","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":40955,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eLoad-deflection curve for PKSC deep beams with vertical shear reinforcement\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/739eeef99b6fa803ccb5561a.png"},{"id":93961913,"identity":"1328633f-501b-4f17-93dd-a8ac3ce28527","added_by":"auto","created_at":"2025-10-20 17:15:11","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":34774,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eLoad-deflection curve for NWC deep beams with vertical shear reinforcement\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/0d53e017c4a38e0fe4a1c906.png"},{"id":93962512,"identity":"b2dd281a-10d8-47e5-ac13-25b7b0fbd7c7","added_by":"auto","created_at":"2025-10-20 17:23:27","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4765415,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7376026/v1/77af9bf5-8817-4b5c-b4f8-09dd4c0becc1.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The Influence of Palm Kernel Shell on the Mechanical Strength Properties of Reinforced Concrete Deep Beams","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eConcrete is one of the most widely utilized construction materials across the globe, which has significantly increased its demand within the industry (Adinkrah-Appiah et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). This rise in demand has consequently led to higher consumption of coarse aggregates, a key component of concrete that functions primarily as an economic filler in construction. Over the years, natural rock types of igneous, metamorphic, and sedimentary origin\u0026mdash;such as granite, basalt, flint, and limestone\u0026mdash;have commonly been used as coarse aggregates for concrete production (Adinkrah-Appiah et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Adinkrah-Appiah, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Adinkrah-Appiah et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; BS 812, Part 1:1975). Their physical qualities, including hardness, inertness, particle shape and texture, gradation, moisture content, specific gravity, soundness, and bulk density, make them suitable for this purpose. This practice has been standard in both maintenance works in advanced economies and new construction projects in developing countries. However, heavy reliance on natural rock resources is creating environmental concerns (Obeng et al., \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Adinkrah-Appiah, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2006\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eAdditionally, the continuous extraction of aggregates from ecological sites has made concrete relatively expensive. This is largely due to the high cost of transporting aggregates over long distances, coupled with regulatory restrictions imposed by environmental authorities on quarrying activities. These challenges highlight the need to explore alternative coarse aggregate materials to either replace or supplement natural sources. Numerous studies on waste products\u0026mdash;such as coal ash, blast furnace slag, fiberglass, plastics, sludge pellets, ceramic waste, asphalt debris, metal scraps, waste clay pots, polypropylene, and recycled concrete\u0026mdash;have reported promising results as substitutes for conventional aggregates (Abeka et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Adinkrah-Appiah et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Obeng et al., \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Nimo-Boakye et al., \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Adinkrah-Appiah, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Adom-Asamoah et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Adinkrah et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Adinkrah-Appiah \u0026amp; Obour, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Adinkrah-Appiah \u0026amp; Kpamma, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2013\u003c/span\u003e; Adinkrah-Appiah \u0026amp; Obour, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; Adinkrah-Appiah, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2006\u003c/span\u003e; Emmitt \u0026amp; Gorse, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; Moulinier et al., \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). Some research has also investigated agricultural wastes as partial replacements for cement to improve performance and promote environmentally friendly construction (Assiamah et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Assiamah et al., \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Assiamah et al., \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Many of these waste products fall under artificial lightweight aggregates (Teo et al., \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2006\u003c/span\u003e), whose application in developed countries has contributed significantly to infrastructure development (Mahmud et al., \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). Since the mechanical and physical properties of aggregates influence the strength, ductility, and durability of concrete, it is essential to assess the performance of these alternatives before widespread adoption.\u003c/p\u003e\u003cp\u003ePalm Kernel Shell (PKS), a by-product of palm kernel oil extraction, has recently gained attention as a potential lightweight coarse aggregate in concrete production due to its favorable properties (Alengaram et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). Studies on PKS concrete (PKSC) reveal that it performs well in compression, shear, flexure, ductility, aggregate interlock, and bonding with steel reinforcement (Teo et al., \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2006\u003c/span\u003e; Alengaram et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2008\u003c/span\u003e; Adinkrah-Appiah et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). PKSC beams, in particular, have demonstrated higher ductility than conventional normal-weight concrete (NWC) beams (Teo et al., \u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e2009\u003c/span\u003e; Alengaram et al., 2011; Shafigh et al., \u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). For instance, Alengaram et al. (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2008\u003c/span\u003e) observed that PKSC beams achieved a displacement ductility ratio of 1.7 compared to NWC beams. Teo et al. (\u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2006\u003c/span\u003e) concluded that the promising results from PKS as a lightweight aggregate indicate its suitability for structural concrete, especially in affordable housing and in seismic zones, where its low weight and ductility are advantageous.\u003c/p\u003e\u003cp\u003eReinforced concrete (RC) beams are known to exhibit reduced shear strength as their depth increases, a phenomenon referred to as the size effect (Ghugal \u0026amp; Dahake, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; Appa Rao \u0026amp; Sundaresan, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). Nevertheless, shear strength generally improves as the shear span-to-depth ratio (a/d) decreases (Bre\u0026ntilde;a \u0026amp; Roy, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). Based on this, RC beams are classified as slender or deep beams (Adinkrah-Appiah \u0026amp; Adom-Asamoah, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). Regions where the shear span is less than twice the beam depth are termed disturbed regions (D-regions), where arch action dominates over beam action (ACI-318, 2008; Shuraiam, 2012). Deep beams, characterized by the presence of D-regions, tend to fail through brittle shear mechanisms (ACI-318, 2008; Appa Rao \u0026amp; Kunal, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2007\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIn high-rise buildings, deep beams often serve as transfer girders, where sufficient ductility is vital to resist various loads, including seismic forces. Given its lightweight nature and excellent ductility characteristics, PKSC emerges as a promising material for constructing RC deep beams in tall structures. This study, therefore, examines the shear strength and ductility performance of reinforced PKSC deep beams and compares them with equivalent NWC deep beams.\u003c/p\u003e"},{"header":"2. Experimental design","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1 Materials\u003c/h2\u003e\u003cp\u003ePKS were collected from the waste left over by a local oil production mill in Sunyani Municipal, until an appreciable amount was obtained. The sand was obtained from Chiraa in Sunyani, and met the requirement specified by British Standard Institution (BS EN 12620:2002\u0026thinsp;+\u0026thinsp;A1:2008). Machine crushed angular granite aggregate was used as coarse aggregate with sizes varying from 10mm to 19mm from a local source. The specific gravity of coarse aggregate was 2.68, the fineness modulus was 6.5 and the water absorption was 0.7 percent, which were all conducted in accordance with the physical property of coarse aggregate BS 812: Part 2: 1995 and BS EN 933-1:1997. After procurement, the sand was air dried to constant weight Ordinary Portland cement 42.5 R in the super rapid grade, a product by GHACEM Ltd in Ghana was used for the study. It also conforms to the specifications in British Standard (BS 12, \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e1996\u003c/span\u003e). The water used for this study was clean and did not contain any dangerous organic or chemical content. It was obtained from free-flowing tap.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2 Methods\u003c/h2\u003e\u003cp\u003eShetty (\u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e2005\u003c/span\u003e) notes that the mix design for lightweight concrete is typically determined through trial batching. Following this approach, a grade 30 concrete, designated as PKSC30, was developed, cast, and tested for the reinforced PKS deep beams. The mix proportions adopted a sand-to-cement ratio of 1.8 and a PKS-to-cement ratio of 0.8, in line with the findings of Alengaram et al. (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). For comparison, another concrete mix incorporating normal weight aggregate (granite) was prepared, labeled NWC30, with a target compressive strength of 30 MPa. The detailed mix proportions for both PKSC30 and NWC30 are presented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eMix Proportions for Concrete Samples\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eConcrete mix\u003c/p\u003e\u003cp\u003eDesign\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e28-day Target Cube\u003c/p\u003e\u003cp\u003eStrength (N/mm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCement Content\u003c/p\u003e\u003cp\u003e(Kg/m\u003csup\u003e3\u003c/sup\u003e)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eWater/ Cement Ratio (W/C)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eSand/ Cement Ratio (S/C)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eCoarse Aggregate/ Cement Ratio (A/C)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eSuper-Plasticizer (%)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePKSC30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e450\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNWC30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e350\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e4.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eA total of three beam pairs, comprising PKSC and NWC beams with and without shear reinforcement, were designed to fail primarily in shear. To prevent premature anchorage failure, adequate reinforcement anchorage was ensured by extending the reinforcement 150 mm beyond the support centerlines. Each beam was reinforced with 1.0% mild steel longitudinal reinforcement, having a yield strength of 413 MPa and an elongation capacity of 22%, and was cast in timber formwork.\u003c/p\u003e\u003cp\u003eThe principal experimental variables considered included the shear span-to-effective depth ratio (a/d\u0026thinsp;=\u0026thinsp;1.0, 1.5, and 2.0), the Shear Reinforcement Index (SRI), and the concrete type. All beams had a rectangular cross-section measuring 150 mm in width and 350 mm in overall depth. The general notation adopted for beam identification followed the format C/A/I, where:\u003c/p\u003e\u003cp\u003eC represents the concrete type, with P for PKSC and N for NWC,\u003c/p\u003e\u003cp\u003eA denotes the a/d ratio, which could be 1.0, 1.5, or 2.0, and\u003c/p\u003e\u003cp\u003eI signifies the shear reinforcement index (SRI), with W0 for SRI\u0026thinsp;=\u0026thinsp;0.0% and V8 for SRI\u0026thinsp;=\u0026thinsp;0.8%.\u003c/p\u003e\u003cp\u003eThe shear reinforcement index (SRI) was calculated using Eq.\u0026nbsp;1. Beam details are presented in Tables\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, covering deep beams without shear reinforcement and those with vertical shear reinforcement, respectively, while Fig.\u0026nbsp;1 illustrates a PKSC deep beam specimen prepared for testing.\u003c/p\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:SRI={A}_{s}{f}_{y}/{S}_{v}{b}_{v}\\)\u003c/span\u003e\u003c/span\u003e% Eq.\u0026nbsp;1\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003ePKSC and NWC deep beams without shear reinforcement\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBeam ID\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eEffective depth d (mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eEffective Span L (mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eShear Span, a (mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(a/d)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e6mm shear reinforcement spacing (mm)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eP/1.0/W0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e312\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e625\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e312.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eP/1.5/W0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e312\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e940\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e470.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eP/2.0/W0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e312\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1250\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e625.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eN/1.0/W0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e312\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e625\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e312.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eN/1.5/W0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e312\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e940\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e470.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eN/2.0/W0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e312\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1250\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e625.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Results and Discussions","content":"\u003cp\u003eThe results of the mechanical property tests on the coarse aggregates and the resulting concrete types were recorded and analyzed.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3: PKSC and NWC deep beams with vertical shear reinforcement\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"493\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBeam ID\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEffective depth \u0026nbsp; \u0026nbsp; d (mm)\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEffective \u0026nbsp;Span \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;L (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eShear Span, a (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e(a/d)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e6mm shear reinforcement spacing (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003eP/1.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003e312\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e625\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e312.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003eP/1.5/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003e312\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e940\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e470.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003eP/2.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003e312\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e1250\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e625.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003eN/1.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003e312\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e625\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e312.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003eN/1.5/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003e312\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e940\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e470.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003eN/2.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003e312\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e1250\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e625.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e3.1 Mechanical Tests on Aggregates\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe laboratory characterization of coarse aggregates (Table 4) revealed notable differences between palm kernel shell (PKS) and granite aggregates. The PKS exhibited an Aggregate Impact Value (AIV) of 4.88%, while granite recorded 9.73%. For comparison, Teo et al. (2009) reported an AIV of 7.51% for PKS, suggesting that the PKS used in this study demonstrated superior resistance to impact loading. Although both aggregate types met the British Standard (BS 882, 1983) specification for maximum allowable AIV, the PKS value was approximately half of that for granite, indicating a higher relative toughness. Since resistance to sudden impact significantly affects the load-carrying capacity of concrete, these results suggest that PKS aggregate concrete could outperform granite-based concrete in impact-sensitive applications.\u003c/p\u003e\n\u003cp\u003eSimilarly, the Aggregate Crushing Value (ACV) tests showed that PKS recorded 2.33% compared to 17.95% for granite. Both values are within the BS 812 (1983) limit of 35%. However, the PKS result represents only about 13% of the granite value, reflecting a much higher resistance to crushing. This finding is consistent with observations by Teo et al. (2009), who reported an ACV of 8% for PKS, again highlighting that the PKS used in this investigation exhibits better crushing resistance. The reduced production of fines from PKS under load further corroborates its toughness.\u003c/p\u003e\n\u003cp\u003eThe relatively lower AIV and ACV values obtained for PKS compared to granite imply that PKS concrete is likely to exhibit improved ductility and energy absorption under compressive and impact loads, supporting earlier findings on the enhanced deformability of PKS-based lightweight concrete (Teo et al., 2009; Shafigh et al., 2011). Furthermore, abrasion resistance tests showed a value of 7.7% for PKS compared to 31.9% for granite, underscoring the higher wear resistance of PKS aggregates. Collectively, these results point to PKS as a promising coarse aggregate, capable of contributing to the development of lightweight concrete with superior ductility and durability characteristics.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4: Physical Characteristics of PKS and Granite Aggregates\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eProperties\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePKS\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGranite\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpecifications\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eGrain size (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e3 \u0026ndash; 18\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e6.3 - 20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e12.5 maximum for PKS (Teo et al 2006)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eShell thickness, mm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1 \u0026ndash; 3\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e0.5-3 (Teo et al 2006)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eSpecific gravity\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e2.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e1.17 for PKS (Teo et al 2006)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eBulk unit weight, kg/m\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e588.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e917.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e500-600 for PKS (Teo et al. 2006)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eFineness Modulus\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e4.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e5.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e2-4 for fine aggregates and 4-6 for coarse aggregates\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003e24-Hour Water Absorption, %\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e6.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e33 for PKS (Teo et al. 2006); \u0026le; 25 for normal weight (BS812: Part 107)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eAggregate Impact Value, %\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e4.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e9.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026le; 25% (BS812: 1983)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eAggregate Crushing Value, %\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e2.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e17.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026le; 35% (BS812:1983)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eFlakiness Index (%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e38.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e24.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026le; 45% (for \u0026lt; 20mm, BS812-105)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eElongation Index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e16.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e22.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026le; 45% (for \u0026lt; 20mm, BS812-105)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 211px;\"\u003e\n \u003cp\u003eLos Angeles Abrasion (%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e7.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e31.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026lt; 50 (BS812: 1983)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e3.2 Tests on Hardened Concrete Samples\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe mechanical properties of PKSC and NWC are summarized in Table 5. The modulus of elasticity (E) of PKSC was measured at 12.28 GPa, compared with 28.5 GPa for NWC, indicating that the E-value of PKSC is approximately 43% of that of its normal-weight counterpart. This finding is consistent with established trends for lightweight concrete, where E-values typically range between 10\u0026ndash;24 GPa (FIP Manual, 1983). The reduced stiffness of PKSC explains its susceptibility to larger deflections under load, a common drawback of lightweight concretes.\u003c/p\u003e\n\u003cp\u003eComparable results have been documented in previous studies. Alengaram et al. (2008) reported an E-value of 10 GPa for PKSC, which was about 33% of the corresponding NWC, while Shafigh et al. (2011) found values between 10.8 and 18.4 GPa for PKSC. The value obtained in the present study therefore aligns well with the reported range, strengthening the evidence that PKSC consistently develops lower elastic modulus relative to NWC, despite comparable compressive strengths.\u003c/p\u003e\n\u003cp\u003eThe relatively lower modulus of elasticity, combined with the previously demonstrated ductility advantages of PKSC (Teo et al., 2006; Alengaram et al., 2011), suggests that PKSC beams may undergo greater deformations but can dissipate energy more effectively than NWC beams. These mechanical property results support the proposition of PKSC as a suitable material for structural applications where ductility and lightweight characteristics are beneficial, such as in seismic regions and high-rise structures.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5: Modulus of Elasticity, Splitting Tensile Strength and Modulus of Rapture Values for Concrete Samples\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType of Concrete\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eModulus of Elasticity\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(E-value) (GPa)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMaximum Strain\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSplitting Tensile Strength (KPa)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eModulus of Rupture (MoR)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(MPa)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003ePKSC30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e12.28\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e0.0026\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e1.80\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e1.19\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003eNWC30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e28.5\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e0.0018\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e3.53\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e2.88\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe compressive strength of the two types of concrete is recorded in Table 6. The 28-day compressive strength results were 33.70 and 42.93 MPa for the PKSC and the NWC samples respectively, showing a higher compressive strength for the NWC than the PKSC. The development of the compressive strength with time is shown in Figure 2, portraying negligible strength development at latter days for the PKSC compared to the NWC.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 6: Cube Compressive Strength of Concrete\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 109px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eConcrete Grade\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 378px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCube Compressive Strength (MPa)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e3 Days\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e7 Days\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e28 Days\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e90 Days\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 109px;\"\u003e\n \u003cp\u003ePKSC30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e21.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e27.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e33.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 101px;\"\u003e\n \u003cp\u003e33.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 1px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 109px;\"\u003e\n \u003cp\u003eNWC30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e34.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e37.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e42.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 101px;\"\u003e\n \u003cp\u003e48.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 1px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e3.3 Shear Strength Characteristics of Deep Beam Samples\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe deep beam specimens without shear reinforcement predominantly failed by \u003cstrong\u003estrut action through diagonal splitting\u003c/strong\u003e, characterized by the rupture of the concrete struts between the loading and support points, accompanied by a loud explosive sound at failure. This mode of failure is typical of deep beams where the load is primarily transferred through compression struts rather than flexural action (Appa Rao \u0026amp; Kunal, 2007; ACI-318, 2008). Both PKSC and NWC specimens displayed this diagonal-splitting strut failure, indicating no fundamental difference in the failure mechanism between the two concrete types.\u003c/p\u003e\n\u003cp\u003eIn terms of crack propagation, \u003cstrong\u003eflexural cracks\u003c/strong\u003e first appeared at mid-span as the load was applied. With further loading, \u003cstrong\u003ediagonal cracks\u003c/strong\u003e developed, extending from the bottom corners of the support plates towards the load application points at the top of the beam. These crack patterns, observed in both PKSC and NWC beams, are consistent with the behaviour of deep beams reported in the literature, where flexural cracks precede shear-induced diagonal cracks (Ghugal \u0026amp; Dahake, 2012; Shuraim, 2012).\u003c/p\u003e\n\u003cp\u003eRepresentative examples of the observed failure modes and crack distributions are presented in Figures 3a and 3b. The similarity in crack initiation and failure progression between PKSC and NWC beams suggests that PKSC can replicate the shear behaviour of conventional concrete in deep beam applications, while potentially offering additional ductility benefits as reported in earlier PKSC studies(Teo et al., 2006; Alengaram et al., 2011).\u003c/p\u003e\n\u003cp\u003eIn contrast to beams without shear reinforcement, specimens incorporating vertical stirrups exhibited a more \u003cstrong\u003eductile failure mode\u003c/strong\u003e, characterized by a greater number of cracks with comparatively smaller widths prior to failure. PKSC beams developed a larger number of cracks overall and exhibited wider crack openings at ultimate load than the corresponding NWC beams, reflecting the influence of the lightweight aggregate on crack propagation and strain distribution. The crack development sequence began with the formation of multiple flexural cracks under initial loading, followed by the gradual emergence of diagonal strut cracks extending between the support and loading plates. These diagonal cracks widened progressively until failure occurred. Unlike the explosive failures observed in beams without shear reinforcement, the reinforced beams failed more silently, with the failure mechanism dominated by \u003cstrong\u003eshear-compression crushing of the struts\u003c/strong\u003e. Representative crack patterns are illustrated in Figures 4a and 4b.\u003c/p\u003e\n\u003cp\u003eThe load history further demonstrated that the \u003cstrong\u003eshear strength of both PKSC and NWC beams increased as the shear span-to-depth ratio (a/d) decreased\u003c/strong\u003e, consistent with arch action principles in deep beams (Ashour et al., 2003; Londhe, 2011). For example, the ultimate shear strength of PKSC beams without shear reinforcement increased from 142 kN (P/2.0/W0) to 190 kN (P/1.5/W0), and further to 226 kN (P/1.0/W0), as the a/d ratio decreased from 2.0 to 1.5 and then to 1.0, respectively (Table 4). These results represent a \u003cstrong\u003e34% strength increase\u003c/strong\u003e when the ratio was reduced from 2.0 to 1.5 and a further \u003cstrong\u003e19% increase\u003c/strong\u003e when reduced from 1.5 to 1.0.\u003c/p\u003e\n\u003cp\u003eThis trend highlights the critical role of the a/d ratio in governing the shear capacity of PKSC beams, mirroring behaviour long established for NWC beams (Ghugal \u0026amp; Dahake, 2012; Appa Rao \u0026amp; Sundaresan, 2014). The improved performance of PKSC beams at lower a/d ratios demonstrates their capacity to exploit strut-and-tie action effectively, while their higher ductility relative to NWC offers additional benefits for applications in seismic and high-rise structures.\u003c/p\u003e\n\u003cp\u003eThis significant response of the shear strength of PKSC deep beams to the a/d ratio confirms that the shear strength of a deep beam fundamentally depends on its a/d ratio, and that the a/d ratio is the overriding parameter that affects the shear strength of a deep beam, as has been found by other researchers (Ashour et al. 2003; Londhe, 2011). The corresponding NWC in the study also produced similar results. Comparison of the shear capacities of the PKSC and NWC deep beams is better achieved by normalizing the ultimate loads with the square-root of the corresponding 28-day cube compressive strength of the concrete. Table 7 shows that the PKSC deep beam samples produced higher normalized failure loads of 38.9, 32.7 and 24.5 MPa for a/d ratios of 1.0, 1.5 and 2.0 respectively, whilst for the NWC, the normalized failure loads were 34.2, 25.6 and 24.4 for a/d ratios of 1.0, 1.5 and 2.0 respectively for the beams without shear reinforcement. Similarly, for the beams with vertical shear reinforcement, the normalized loads were 39.9, 38.9 and 38.6 N/mm\u003csup\u003e2\u003c/sup\u003e, whilst the NWC deep beam samples produced 35.1, 34.8 and 34.2 N/mm\u003csup\u003e2\u003c/sup\u003e for the a/d of 1.0, 1.5 and 2.0 respectively. The results show that the PKSC deep beams exhibit higher normalized shear strength characteristics compared to the NWC deep beams. This confirms the result of Alengaram et al. (2011) which reported higher shear strength for PKSC slender beams compared to the control NWC beams.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4 Crack and Deflection Response of PKSC and NWC Deep Beams\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe cracking patterns of the tested beams, as summarized in Table 7, revealed consistent trends between PKSC and NWC specimens. With the exception of specimen N/1.5/W0, all beams first developed \u003cstrong\u003eflexural cracks\u003c/strong\u003e under increasing load, which were subsequently followed by the formation of diagonal strut cracks at higher load levels. For the PKSC deep beams without shear reinforcement, the first flexural cracks appeared at load levels between \u003cstrong\u003e41% and 54% of the ultimate load\u003c/strong\u003e, while the corresponding NWC beams exhibited first flexural cracks between \u003cstrong\u003e40% and 67% of their ultimate load capacity\u003c/strong\u003e. Similarly, in beams with vertical shear reinforcement, PKSC specimens showed initial flexural cracks between \u003cstrong\u003e26% and 53%\u003c/strong\u003e of ultimate load, whereas the range for NWC specimens was \u003cstrong\u003e42% to 75%\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eFollowing the initiation of flexural cracks, \u003cstrong\u003estrut (diagonal) cracks\u003c/strong\u003e appeared and became the dominant cracking mode. These diagonal cracks propagated from the bottom support region towards the upper loading plates and increased both in width and length with continued loading, eventually governing the ultimate failure of the beams. For PKSC deep beams without shear reinforcement, first strut cracks appeared at \u003cstrong\u003e46%\u0026ndash;60%\u003c/strong\u003e of the ultimate load, while NWC beams showed a wider range of \u003cstrong\u003e46%\u0026ndash;72%\u003c/strong\u003e. With vertical shear reinforcement, first strut crack loads ranged between \u003cstrong\u003e41% and 70%\u003c/strong\u003e for PKSC and between \u003cstrong\u003e53% and 91%\u003c/strong\u003e for NWC.\u003c/p\u003e\n\u003cp\u003eThe ratio of both first flexural and strut crack loads to ultimate load was found to \u003cstrong\u003eincrease as the a/d ratio decreased\u003c/strong\u003e for both concrete types, regardless of the presence of shear reinforcement. This trend is consistent with the enhanced arching action at lower shear span-to-depth ratios, which delays the initiation of diagonal cracking (Ashour et al., 2003; Londhe, 2011).\u003c/p\u003e\n\u003cp\u003eA key distinction emerged between the two concrete types: at all a/d ratios, \u003cstrong\u003ePKSC beams developed first flexural and strut cracks at lower percentages of ultimate load compared to NWC beams\u003c/strong\u003e. This behaviour implies that PKSC beams undergo more progressive crack development and higher inelastic deformation prior to failure, while NWC beams display relatively brittle responses. At ultimate load, PKSC beams exhibited \u003cstrong\u003elarger crack widths\u003c/strong\u003e than NWC beams, further supporting their superior energy absorption capacity and ductility. This finding aligns with earlier observations on PKSC slender beams, where higher displacement ductility was recorded compared to normal-weight counterparts (Alengaram et al., 2008). Consequently, PKSC emerges as a promising material for deep beam applications, where brittle failure is a dominant concern (Appa Rao \u0026amp; Kunal, 2007).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 7: Shear strength characteristics of deep beam samples\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"625\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBeam ID\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ea/d\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ef\u003csub\u003ecu\u003c/sub\u003e (MP)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLoad at first Crack (KN)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMax. Crack Width (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMax. \u0026nbsp;Mid-Span Deflection (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP\u003csub\u003emax\u003c/sub\u003e (KN)\u003csub\u003e\u0026nbsp;\u003c/sub\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNom-alized P\u003csub\u003emax\u003c/sub\u003e (N/mm\u003csup\u003e2\u003c/sup\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFailure Mode\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFlex-ural\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eStrut\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eP/1.0/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e33.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e104\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e0.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e2.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e226\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003e38.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/DS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eP/1.5/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e33.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e1.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e3.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e190\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003e32.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/DS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eP/2.0/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e33.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e3.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e4.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e143\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003e24.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/DS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eP/1.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e33.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e160\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 60px;\"\u003e\n \u003cp\u003e0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e2.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e230\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e39.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/SC\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eP/1.5/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e33.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 60px;\"\u003e\n \u003cp\u003e1.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e4.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e226\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e38.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/SC\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eP/2.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e33.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 60px;\"\u003e\n \u003cp\u003e0.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e3.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e224\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e38.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/SC\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eN/1.0/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e42.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e150\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e162\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e2.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e224\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003e34.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/DS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eN/1.5/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e42.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e2.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e4.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e168\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003e25.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/DS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eN/2.0/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e42.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e108\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e1.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e2.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e160\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003e24.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/DS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eN/1.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e42.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e172\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e210\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 60px;\"\u003e\n \u003cp\u003e0.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e2.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e230\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e35.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/SC\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eN/1.5/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e42.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e124\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 60px;\"\u003e\n \u003cp\u003e0.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e2.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e228\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e34.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/SC\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eN/2.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e42.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e118\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 60px;\"\u003e\n \u003cp\u003e0.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e2.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e224\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e34.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eSF/SC\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eSF=Strut failure, DS=Diagonal splitting, SC=Shear compression\u003c/p\u003e\n\u003cp\u003eThe deflection of the PKSC and NWC deep beams without shear reinforcement is as shown in Figures 5 and 6, whilst that for the beams with vertical shear reinforcement is portrayed in Figures 7 and 8. The load-deflection response of the PKSC deep beams with and without shear reinforcement shows that as the a/d ratio increased from 1.0 through 1.5 to 2.0, the stiffness of the beams reduced whilst the ultimate deflection at failure increased (Figures 5 and 7). This implies that, PKSC deep beams exhibit similar behaviour as reinforced NWC deep beams, as a decrease in a/d ratio results in an increase in the stiffness and hence the shear strength, as found for NWC (Ashour et al. 2003; Londhe, 2011). The NWC deep beams in the study showed similar trends as presented in Figures 6 and 8.\u003c/p\u003e\n\u003cp\u003eHowever, in all cases the NWC deep beam samples exhibited higher resistance to deflection compared to the PKSC deep beams. This is portrayed by the relative steeper slopes of the NWC deep beam curves, for both beams with and without shear reinforcement, indicating that NWC deep beams have higher stiffness, and hence exhibit brittle failure, compared to corresponding PKSC deep beams. The PKSC deep beams experienced larger deflections in all cases at failure compared to the NWC deep beams. This confirms the findings of Alengaram et al. (2008) that PKSC slender beams exhibit higher deflections at failure and hence possess higher ductility characteristics at failure than similar NWC slender beams.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.5 Ductility of PKSC and NWC deep beams\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDuctility, defined as the capacity of a structural element to absorb energy and undergo significant inelastic deformation, is a key property in reinforced concrete design because it permits stress redistribution and provides warning before ultimate failure occurs (Duthinh \u0026amp; Starnes, 2001; Adom-Asamoah \u0026amp; Afrifa, 2013). In structural concrete, ductility may be evaluated in terms of curvature, rotation, or displacement. This study employed the \u003cstrong\u003edisplacement ductility ratio (\u0026mu;)\u003c/strong\u003e, expressed as the ratio of ultimate deflection to the deflection at which the flexural reinforcement yields. A higher ductility ratio indicates a greater capacity of the member to sustain deformation before collapse. Ratios between \u003cstrong\u003e3 and 5\u003c/strong\u003e are generally regarded as adequate for structural members, as they signify the ability to accommodate large displacements under dynamic actions such as earthquakes (Teo et al., 2006).\u003c/p\u003e\n\u003cp\u003eIn this investigation, the yield points of the flexural steel were identified from the load\u0026ndash;deflection curves, specifically at the second stage where a noticeable change in slope occurs, following the procedure recommended by Adom-Asamoah and Afrifa (2013). Analysis of the displacement ductility ratios presented in Tables 8 and 9 revealed that \u003cstrong\u003ePKSC deep beams without shear reinforcement consistently exhibited higher ductility values compared to corresponding NWC beams across all a/d ratios\u003c/strong\u003e. A similar observation was made for beams with vertical shear reinforcement (Tables 10 and 11), where PKSC specimens again demonstrated superior ductility performance.\u003c/p\u003e\n\u003cp\u003eThe enhanced ductility of PKSC beams may be attributed to the lightweight aggregate\u0026rsquo;s influence on crack distribution and post-yield behaviour, which promotes progressive deformation rather than abrupt failure. In general, ductility in RC beams is influenced by several factors including longitudinal reinforcement, web reinforcement, shear span-to-depth ratio, and compressive strength of the concrete (Appa Rao \u0026amp; Injaganeri, 2013). For a given reinforcement configuration, an increase in concrete compressive strength is associated with improved ductility (Lin \u0026amp; Lee, 2003).\u003c/p\u003e\n\u003cp\u003eThe higher ductility indices obtained for PKSC in this study reinforce earlier findings on the superior deformability of lightweight aggregate concretes (Teo et al., 2006; Alengaram et al., 2011). These results underscore the potential of PKSC as a suitable material for applications requiring high energy absorption and inelastic deformation capacity, such as in seismic regions and critical load-bearing components in high-rise construction.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 8: Displacement Ductility Ratio (\u0026mu;) of PKSC deep Beams without Shear Reinforcement\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBeam ID\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ea/d Ratio\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eUltimate Deflection (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDeflection at Yield (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDuctility Ratio\u0026nbsp;\u003c/strong\u003e(\u0026micro;)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003eP/1.0/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e2.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e0.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e2.32\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003eP/1.5/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e3.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e1.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e3.42\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003eP/2.0/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e0.94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e4.26\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003eAVERAGE\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e3.33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003eSTDEV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e0.97\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003eCV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIntrinsic factors that contribute to good ductility behaviour of a concrete are toughness and good shock absorbing capacity of the aggregates used to form the concrete (Teo et al, 2006; Adom-Asamoah and Afrifa, 2013). This is measured by the low aggregate crushing value (ACV) and aggregate impact value (AIV) of the PKSC aggregate. For instance, BS812: 1983 code specifies maximum ACV and AIV values of 35% and 25% respectively for good and sound concrete aggregates. The ACV and AIV obtained for the PKS aggregate were 2.33% and 4.88% respectively, whilst for the granite aggregate used for the NWC, the values were 17.95% and 9.73% (Table 4). Although all the two aggregates satisfy the BS812: 1983 requirements for both ACV and AIV, the PKS aggregate exhibited relatively lower values for both parameters and hence confirms the higher ductility performance characteristics of the PKSC deep beams compared to the NWC deep beam samples in the study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 9: Displacement Ductility Ratio (\u0026mu;) of NWC deep Beams without Shear Reinforcement\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBeam ID\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ea/d Ratio\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eUltimate Deflection (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDeflection at Yield (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDuctility Ratio\u0026nbsp;\u003c/strong\u003e(\u0026micro;)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eN/1.0/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e1.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e1.22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eN/1.5/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e4.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e1.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e3.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eN/2.0/W0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e2.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e1.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e2.03\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eAVERAGE\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e2.09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eSTDEV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e0.90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eCV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 10: Displacement Ductility Ratio (\u0026mu;) of PKSC deep Beams with Vertical Shear Reinforcement\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBeam ID\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ea/d Ratio\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eUltimate Deflection (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDeflection at Yield (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDuctility Ratio\u0026nbsp;\u003c/strong\u003e(\u0026micro;)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eP/1.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e2.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 108px;\"\u003e\n \u003cp\u003e1.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e2.52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eP/1.5/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e4.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 108px;\"\u003e\n \u003cp\u003e0.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e4.87\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eP/2.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e3.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 108px;\"\u003e\n \u003cp\u003e0.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e4.15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eAVERAGE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e3.85\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eSTD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e1.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eCV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 11: Displacement Ductility Ratio (\u0026mu;) of NWC deep Beams with Vertical Shear Reinforcement\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBeam ID\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ea/d Ratio\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eUltimate Deflection\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDeflection at Yield\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 126px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDuctility Ratio\u003c/strong\u003e(\u0026micro;)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eN/1.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e2.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e2.92\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eN/1.5/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e2.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e1.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e2.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 133px;\"\u003e\n \u003cp\u003eN/2.0/V8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e2.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e0.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e4.18\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eAVERAGE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e3.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eSTD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 126px;\"\u003e\n \u003cp\u003e1.08\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eCV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 126px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 126px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe experimental results demonstrated clear differences in ductility between PKSC and NWC deep beams. For specimens \u003cstrong\u003ewithout shear reinforcement\u003c/strong\u003e, the average displacement ductility ratios (\u0026mu;) were \u003cstrong\u003e3.3 for PKSC\u003c/strong\u003e and \u003cstrong\u003e2.1 for NWC\u003c/strong\u003e, yielding a relative ductility factor of \u003cstrong\u003e1.6\u003c/strong\u003e in favour of PKSC. When \u003cstrong\u003evertical shear reinforcement\u003c/strong\u003e was introduced, the average ductility ratios increased to \u003cstrong\u003e3.9 for PKSC\u003c/strong\u003e and \u003cstrong\u003e3.1 for NWC\u003c/strong\u003e, corresponding to a relative ductility of \u003cstrong\u003e1.3\u003c/strong\u003e. These findings indicate that while the addition of shear reinforcement enhanced the ductility of both concrete types, the improvement was more pronounced in NWC beams. This suggests that PKSC inherently possesses superior ductility characteristics, whereas NWC requires reinforcement to achieve comparable levels of inelastic deformation. Similar conclusions have been reported by Appa Rao and Injaganeri (2013), who identified web reinforcement as a key factor in improving ductility behaviour in RC beams.\u003c/p\u003e\n\u003cp\u003eThe implication of this result is that \u003cstrong\u003ePKSC deep beams may require less web reinforcement than NWC beams to achieve satisfactory ductility\u003c/strong\u003e, potentially leading to cost savings in reinforcement requirements. The intrinsic ductility of PKSC thus reduces dependence on shear reinforcement for crack control and energy dissipation.\u003c/p\u003e\n\u003cp\u003eThese findings are consistent with earlier work on slender beams. Alengaram et al. (2008) reported displacement ductility ratios of \u003cstrong\u003e4.8 for PKSC\u003c/strong\u003e and \u003cstrong\u003e2.8 for NWC\u003c/strong\u003e beams with shear reinforcement, corresponding to a relative ductility of \u003cstrong\u003e1.7\u003c/strong\u003e. Although absolute ductility values are lower in deep beams due to their inherently brittle behaviour (Appa Rao \u0026amp; Kunal, 2007), the relative ductility advantages of PKSC observed in this study (1.3\u0026ndash;1.6) align closely with the slender beam results.\u003c/p\u003e\n\u003cp\u003eThe structural significance of these results lies in the application of PKSC in \u003cstrong\u003edeep beam design for high-rise structures\u003c/strong\u003e, particularly as transfer girders. Deep beams are typically associated with brittle shear-compression failures; thus, the \u003cstrong\u003ehigher ductility of PKSC\u003c/strong\u003e can enhance post-cracking performance and provide critical energy absorption capacity. Moreover, the \u003cstrong\u003elightweight nature of PKSC\u003c/strong\u003e offers an added advantage for seismic design, where reduced self-weight decreases inertial forces. The combination of high ductility and low density makes PKSC a promising material for RC deep beams in earthquake-prone regions, while its enhanced energy absorption also contributes to the higher relative shear strength observed in PKSC beams compared to NWC beams.\u003c/p\u003e"},{"header":"4. Conclusions","content":"\u003cp\u003eBased on the results obtained, the following conclusions were drawn on the use of PKSC for the design of reinforced concrete deep beams:\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003ePKS aggregate possesses lower aggregate crushing, aggregate impact and higher abrasion resistance than normal weight aggregate which makes it a material that produces concrete that absorbs shocks and wearing better than normal weight aggregate concrete.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eStrength development of PKSC is at early age compared to NWC samples. After 28 days, PKSC does not develop any appreciable strength. PKSC develops almost its utmost strength around 7 days.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003ePKSC deep beam samples having a/d of 2.0 and below fail by strut failure through diagonal-splitting with a loud explosion for beams without shear reinforcement; whilst for beams with vertical shear reinforcement, a more ductile failure mode occurs through shear compression without explosion.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eThe shear strength of PKSC deep beams increase as a/d ratio reduces, as has been found for normal weight concrete deep beams.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eThe normalized shear strength of PKSC deep beams is higher than corresponding NWC deep beams at different a/d ratios.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eFirst flexural and strut cracks appear at lower percentages of ultimate loads in PKSC deep beams with and without shear reinforcement than in NWC deep beams. This shows that PKSC deep beams exhibit higher inelastic deformations, and hence exhibit higher ductility characteristics at failure.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eAverage displacement ductility ratio of 3.3 and 2.1 were recorded for PKSC and NWC deep beams without shear reinforcement respectively; whilst for beams with vertical shear reinforcement the average displacement ductility ratios were 3.9 and 3.1 for PKSC and NWC deep beams respectively. This gives a relative displacement ductility ratio of 1.6 and 1.3 existing between PKSC and NWC deep beams without shear reinforcement and with vertical shear reinforcement respectively. This further shows that, the high relative ductility of PKSC deep beams over NWC deep beams reduces as shear reinforcement is introduced as a result of the more brittle NWC improving its ductility at a relatively higher rate with the introduction of shear reinforcement.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors guarantee that this manuscript is not published or not under consideration by any other journal and that the manuscript is original and is their own work.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study are available from the corresponding author upon reasonable request\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing financial interests or personal relationships that may have influenced the work reported in this study\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors received no funding for this research\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll the authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by KA, MA, ROA . The first draft of the manuscript was written by SA, and JO. All the authors commented on previous versions of the manuscript. All the authors have read and approved the final manuscript\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank the anonymous reviewers for their valuable comments and suggestions, which helped improve the quality of this work\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; information\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eKwadwo Adinkrah-Appiah\u003c/strong\u003e is an Associate Professor of Civil Engineering. He has authored several research publications. His research areas include shear strength of reinforced palm kernel shell concrete deep beams, vulnerability of building structures in the seismic zones of Ghana, the use of waste materials as aggregates for concrete and building block production for sustainable construction, the use of lateritic soils for concrete and building block production, lean construction in the Ghanaian construction industry and the economic cost of road accidents in Ghana.\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eMark Adom-Asamoah\u0026nbsp;\u003c/strong\u003eis the Provost of the College of Engineering at the Kwame Nkrumah University of Science and Technology, Kumasi. He is a past Dean of the Faculty of Civil and Geo-Engineering and Head of the Department of Petroleum Engineering. He is a Fulbright Senior Research Fellow, Commonwealth Scholar and British Council Scholar. He was a visiting scholar at the University of Bristol, UK and Arizona State University, USA.\u003cbr\u003e\u0026nbsp;His research interests are behavior of local civil engineering materials and seismic behavior of low-medium seismic regions.\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eRussell O. Afrifa\u003c/strong\u003e is a lecturer in the Civil Engineering Department at Kwame Nkrumah University of Science and Technology (KNUST) and specializes in structural engineering, reinforced concrete design, and structural materials. With a PhD in Civil Engineering and over 15 years of experience as a structural Engineer, Dr. Afrifa brings a wealth of practical knowledge to his academic role. His expertise extends to the design and analysis of reinforced concrete structures, as well as the study of advanced structural materials. Dr. Afrifa\u0026apos;s research aims to increase the safety, durability, and efficiency of infrastructure through innovative engineering solutions\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eSampson Assiamah\u003c/strong\u003e is a lecturer from the Department of Building and Technology, Sunyani Technical University, and is currently pursuing PhD in structural engineering at Kwame Nkrumah University of Science and Technology (KNUST), Department of Civil Engineering. My research interests are related to sustainable construction materials and processing, structural engineering, materials science, construction technology and building science.\u003c/li\u003e\n \u003cli\u003eJ\u003cstrong\u003eacqueline Obeng\u003c/strong\u003e is a lecture from the Department of Civil Engineering, Sunyani Technical University, and is currently holds PhD in structural engineering at KNUST, Department of Civil Engineering. My research interests are related to sustainable construction materials and processing, structural engineering, materials science, construction technology and building science.\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eACI 318 (2008). \u0026ldquo;ACI Committee 318 (2008). Building Code Requirements for Structural Concrete (ACI 318-08) and Commentary\u0026rdquo;. American Concrete Institute, Farmington Hills, MI.\u003c/li\u003e\n \u003cli\u003eAbeka, H. Obeng, J. Sasa, J. Adinkrah-Appiah, K. Obeng-Ankamah, N. Abdulai, M. Koogyah, E. and Okyere, C. (2025). \u0026ldquo;Assessing the Resilience of Palm-Kernel\u0026ndash;Based Concrete to Sodium Chloride and Sulphuric Acid Attack\u0026rdquo;. Journal of Engineering Research and Reports 27 (5):399-410. https://doi.org/10.9734/jerr/2025/v27i51514.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K., Assiamah, S. \u0026amp; Agyeman, S. Effect of partial replacement of sawdust with sand on the properties of sandcrete blocks for sustainable non-load bearing walls in Ghana. \u003cem\u003eDiscov Civ Eng\u003c/em\u003e \u003cstrong\u003e2\u003c/strong\u003e, 95 (2025). https://doi.org/10.1007/s44290-025-00246-4\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. (2018). Non-conventional coarse aggregate concrete for sustainable housing construction in Ghana. Sunyani Technical University International Journal of Technology (STUIJT). Vol 1, Issue 5 - May, 2018, (ISSN 2508\u0026ndash;0997, Online).\u003c/li\u003e\n \u003cli\u003eAdinkrah, K. A., Asamoah, M. A., \u0026amp; Osei, J. B. (2018). Structural Lightweight PKS Concrete without the use of Supplementary Cementing Materials. \u003cem\u003eJournal of Structural Technology\u003c/em\u003e, \u003cem\u003e3\u003c/em\u003e(2), 1-15.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah K, Kpamma EZ, Nimo-Boakye A, Asumadu KT, Obeng-Ankamah N. Annual consumption of crushed stone aggregates in Ghana. J Civil Eng Archit Res. 2016;3(10):1729\u0026ndash;37.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. and Adom-Asamoah, M. (2016). Characterization and Shear Strength Prediction of Reinforced Concrete Deep Beams \u0026ndash; A Review. International Journal of Science and Research (IJSR). ISSN (Online): 2319-7064, Index Copernicus Value (2013): 6.14, Impact Factor (2013): 4.438\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. \u0026amp; Obour, G. D. Fused laterite powder substitution for cement in concrete production. Int Conf Appl Sci Technol Conf Proc. 2017;3(1):100\u0026ndash;5.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. Kpamma, E. Z. Nimo-Boakye, A. Asumadu, K. T. Obeng-Ankamah, N. (2016). Annual consumption of crushed stone aggregates in Ghana. J Civil Eng Archit Res. 2016;3(10):1729\u0026ndash;37.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. (2016). Shear Strength of Reinforced Palm Kernel Shell Concrete Deep Beams. \u0026lrm; LAP LAMBERT Academic Publishing. 1 October 2016b. ISBN-10 3659834459; ISBN-13: \u0026rlm; \u0026nbsp;.978-3659834455\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. Obeng-Ankamah, H. and Abeka, H. K. (2016). Concrete pavement slabs reinforced with steel fibres from discarded vehicle tyres. STU International Journal of Technology (STUIJT) Vol. 1, Issue 1 -April, 2016 (ISSBN: 2508-0997, Online). www.stu.edu.gh.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. Adom-Asamoah, M. and Afrifa, R. O. (2015). Shear Strength Prediction of Palm Kernel Shell RC Deep Beams without Shear Reinforcement. 1st International Conference on Engineering, Science, Technology \u0026amp; Entrepreneurship, 2015. Department of Civil Engineering, K.N.U.S.T. Kumasi. 2015; 472\u0026ndash;492.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. Adom-Asamoah, M. and Afrifa, R. O. (2015). \u0026ldquo;Reducing Environmental Degradation from Construction Activities: The Use of Recycled Aggregates for Construction in Ghana\u0026rdquo;. Journal of Civil Engineering and Architecture Research. Vol. 2, No. 8, 2015, pp. 831-841.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. and Kpamma, E. Z. (2013). Improving the Structural Characteristics of Earth Blocks as an Input of Affordable Housing for Low Income Northern Communities of Ghana. International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2013): 6.14 | Impact Factor (2013): 4.438.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. Obour, D. G. The potential of rice husk ash as a partial replacement for Cement in concrete production in Ghana. 1st International Conference on Infrastructure Development in Africa (ICIDA) Conference Proceedings 2012. Department of Building Technology, K.N.U.S.T., Kumasi. 2012.\u003c/li\u003e\n \u003cli\u003eAdinkrah-Appiah, K. (2006). Salancrete Building Blocks From Mixture of sand, Laterite And Cement For Sustainable housing In Ghana. Sunyani Polytechnic Lecture Series V, Sunyani, Ghana, volume 4, number 1, June 2006. ISBN 0855\u0026ndash;0843. 2021; 157\u0026ndash;175.\u003c/li\u003e\n \u003cli\u003eAdom-Asamoah, M. Banahene J. O. Adinkrah-Appiah, K. (2018). Structural Characteristics of Reinforced Palm Kernel Shell Concrete Deep Beams. Civil Engineering Journal Vol. 4, No. 7, July, 2018. Available online at www.CivileJournal.org.\u003c/li\u003e\n \u003cli\u003eAdom-Asamoah, M. and Afrifa R. O. (2013). Performance evaluation of shear strength of reinforced concrete beams made from phyllite aggregates. A Thesis submitted to the Department of Civil Engineering, KNUST, Kumasi, in partial fulfillment of the requirement for the degree of Doctor of Philosophy. Department of Civil Engineering, College of Engineering.\u003c/li\u003e\n \u003cli\u003eAlengaram, U. J. Jumaat M. Z. and Mahmud, H. (2008). \u0026ldquo;Ductility behaviour of reinforced palm kernel shell concrete beams\u0026rdquo;. Eur. J. Scient. Res. \u003cstrong\u003e23\u003c/strong\u003e(3):406-420.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eAppa Rao, G. and Sundaresan, R. (2014), \u0026ldquo;Size Dependent Shear Strength Of Reinforced Concrete Deep\u003c/li\u003e\n \u003cli\u003eBeams Based On Refined Strut-And-Tie Model\u0026rdquo;. Journal of Frontiers in Construction Engineering. Mar. 2014, \u003cstrong\u003eVol. 3\u003c/strong\u003e Iss. 1, PP. 9-19.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eAppa Rao, G. and Injaganeri, S. S. (2013), \u0026ldquo;Minimum shear reinforcement for optimum ductility of\u003c/li\u003e\n \u003cli\u003ereinforced concrete beams\u0026rdquo;. International Journal of Research in Engineering and Technology. eISSN: 2319-1163, pISSN: 2321-7308. Vol. 2 Issue 10, Oct-2013.\u003c/li\u003e\n \u003cli\u003eAppa Rao G. and Kunal K. (2007). \u0026ldquo;Shear strength of Reinforced Concrete deep beams\u0026rdquo;. FraMOS-\u003cstrong\u003e6\u003c/strong\u003e, 17-22, June, 2007, Catania, Italy, pp. 671-675.\u003c/li\u003e\n \u003cli\u003eAshour, A. F., Alvarez, L. F., and Toropov, V. V. (2003). \u0026quot;Empirical modeling of shear strength of RC deep beams by genetic programming.\u0026quot; Computers and Structures, \u003cstrong\u003e81\u003c/strong\u003e(5), 331-338.\u003c/li\u003e\n \u003cli\u003eAssiamah, S. Kankam, C. K. Adinkrah-Appiah, K. et al. (2025). The impact of burnt sawdust ash from timber species as partial cement replacements on the durability properties for sustainable interlocking blocks. Discov Civ Eng. 2025;2:20. https://doi.org/10.1007/s44290-025-00183-2.\u003c/li\u003e\n \u003cli\u003eAssiamah, S. Kankam, C. K. Adinkrah-Appiah, K. Afrifa, R. O. and Twumasi, J. O. (2024). Effects of burnt sawdust ashes from timber species on the strength properties of laterite-interlocking blocks. Discov Civil Eng. 2024;1(1):87.\u003c/li\u003e\n \u003cli\u003eAssiamah, S. Kankam, C. K. Afrifa, R. O. Adinkrah-Appiah, K. Banahehe, O. J. (2024). Improving tensile strength characteristics and water absorption of laterite interlocking blocks enhanced with different burnt sawdust ash from timber species. J Mater Sci Res Rev. 2024a;7(4):532\u0026ndash;50.\u003c/li\u003e\n \u003cli\u003eAssiamah, S. Kankam, C. K. Adinkrah-Appiah, K. Afrifa, R. O. and Twumasi, J. O. (2024b). Effects of burnt sawdust ashes from timber species on the strength properties of laterite-interlocking blocks. Discov Civil Eng. 2024;1(1):87.\u003c/li\u003e\n \u003cli\u003eAssiamah, S. Kankam, C. K. Adinkrah-Appiah, K. Afrifa, R. O. Jack, Banahene O. J. and Okai, D. (2024c). \u0026nbsp; Influence of burnt sawdust ash from timber species on the chemical strength properties of laterite-interlocking blocks. J Mater Sci Res Rev. 2024c;7(2):252\u0026ndash;61.\u003c/li\u003e\n \u003cli\u003eAssiamah, S. Agyeman, S. Adinkrah-Appiah, K. and Danso, H. (2022). Utilization of sawdust ash as cement replacement for landcrete interlocking blocks production and mortarless construction. Case Stud Constr Mater. 2022. https://doi.org/10.1016/j.cscm.2022.e00945.\u003c/li\u003e\n \u003cli\u003eBre\u0026ntilde;a S. F. and Roy N. C. (2009). \u0026ldquo;Evaluation of Load Transfer and Strut Strength of Deep Beams with\u003c/li\u003e\n \u003cli\u003eShort Longitudinal Bar Anchorages\u0026rdquo;. ACI Structural Journal, V. 106, No. 5 Title no. 106-S63, MS No. S-2008-205.\u003c/li\u003e\n \u003cli\u003eBS812 (1975). \u0026ldquo;Specification of Aggregates for Concrete\u0026rdquo;. British Standard Institute Part 1.\u003c/li\u003e\n \u003cli\u003eBS882 (1983): \u0026ldquo;Specification of Aggregates for Concrete\u0026rdquo;, British Standard Institute. \u0026nbsp; \u0026nbsp;\u003c/li\u003e\n \u003cli\u003eBS 12. (1996). Specification for Portland cement. British Standards Institution.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eBS EN 933-1:1997Testing for geometrical properties of aggregate. Determination of particle size distribution. Sieving method (AMD 15907).\u003c/li\u003e\n \u003cli\u003eBritish Standard EN 12620: (2002). +A1: (2008). Aggregates for concrete masonry units.\u003c/li\u003e\n \u003cli\u003eDuthinh, D. and Starnes, M. (2001). Strength and Ductility of Concrete Beams Reinforced with Carbon FRP\u003c/li\u003e\n \u003cli\u003eand Steel. U.S. Department of Commerce, Technology Administration. Building and Fire Research Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eEmmitt S. and Gorse C. (2010), \u0026ldquo;Introduction to Construction of Buildings. Second Edition\u0026rdquo;. Wiley-Blackwell. ISBN-10:1405 188545.\u003c/li\u003e\n \u003cli\u003eFIP Manual, (1983). \u0026ldquo;FIP Manual of Lightweight Aggregate Concrete\u0026rdquo;, 2 ed. London: Surrey University Press.\u003c/li\u003e\n \u003cli\u003eGhugal Y. M. and Dahake A. G. (2012), \u0026ldquo;Flexural analysis of deep beam subjected to parabolic load using refined shear deformation theory\u0026rdquo;. Applied and Computational Mechanics,\u003cstrong\u003eVol 6\u003c/strong\u003e, (2012), 163\u0026ndash;172.\u003c/li\u003e\n \u003cli\u003eLin and Lee, (2003), \u0026ldquo;Shear Behaviour of High Workability Concrete Beams\u0026rdquo;, ACI Structural Journal, \u003cstrong\u003eVol. 100\u003c/strong\u003e, No.5, Sept.-Oct. 2003, pp. 599-608.\u003c/li\u003e\n \u003cli\u003eLondhe, R. S. (2011), \u0026quot;Shear strength analysis and prediction of reinforced concrete transfer beams in high-rise buildings.\u0026quot; Structructural Engineering Mechanics, \u003cstrong\u003eVol. 37\u0026nbsp;\u003c/strong\u003e(1), 39-59.\u003c/li\u003e\n \u003cli\u003eMacGenley and Choo, 1990; McGenley, T. J. and Choo, B. S. (1990). Reinforced concrete: Design theory and examples. Second Edition. London; New York: E\u0026amp;FN Spon.\u003c/li\u003e\n \u003cli\u003eMahmud, H.B. Majuar, E. Zain, M.F.M. and Hamid, N.B.A.A. (2009). Mechanical Properties and Durability\u003c/li\u003e\n \u003cli\u003eof High Strength Concrete Containing Rice Husk Ash. Journal of advanced concrete technology. \u003cstrong\u003eVol.\u003c/strong\u003e \u003cstrong\u003e79\u003c/strong\u003e (1): 21-30.\u003c/li\u003e\n \u003cli\u003eMoulinier, F. Lane, S. and Dunster, A. (2006), \u0026ldquo;The use of glass as aggregate in in Portland cement concrete\u0026rdquo;. The Waste and Resources Action Programme (WRAP), Banbury, Oxon.\u003c/li\u003e\n \u003cli\u003eNimo-Boakye, A., Nana-Addy, E., Adinkrah-Appiah, K. (2023). Burnt Clay Grinding Pot Waste Powder as a Partial Replacement of Ordinary Portland Cement for Concrete Production. In: Aigbavboa, C., \u003cem\u003eet al.\u003c/em\u003e Sustainable Education and Development \u0026ndash; Sustainable Industrialization and Innovation. ARCA 2022. Springer, Cham. https://doi.org/10.1007/978-3-031-25998-2_73\u003c/li\u003e\n \u003cli\u003eObeng, J., Sasah, J., Adinkrah-Appiah, K. et al. (2025). A comprehensive review of local sustainable materials utilized in concrete production in Ghana. Discov Sustain \u003cstrong\u003e6\u003c/strong\u003e, 400 (2025). https://doi.org/10.1007/s43621-025-00898-3.\u003c/li\u003e\n \u003cli\u003eRogowsky, D. M., MacGregor, J. G. and Ong, S. Y. (1983), \u0026ldquo;Tests of Reinforced Concrete Deep Beams\u0026rdquo;. University of Alberta, Edmonton. Report number: 109.\u003c/li\u003e\n \u003cli\u003eShafigh, P. Jumaat, M. Z. Mahmud, H. and Alengaram, U.J. (2011). \u0026ldquo;A new method of producing high strength oil palm shell lightweight concrete\u0026rdquo;. Mater Des 2011; 32(10):4839\u0026ndash;43.\u003c/li\u003e\n \u003cli\u003eShetty, M. S. (2005), \u0026ldquo;Concrete technology theory and practice\u0026rdquo;. 3rd Multicolor illustrative revised ed., India; 2005.\u003c/li\u003e\n \u003cli\u003eShuraim, A. B. (2012), \u0026ldquo;Behavior and shear design provisions of reinforced concrete D-region beams\u0026rdquo;. Journal of King Saud University \u0026ndash; Engineering Sciences (2013) \u003cstrong\u003e25\u003c/strong\u003e, 65\u0026ndash;74.\u003c/li\u003e\n \u003cli\u003eTeo, D.C.L. Mannan M. A. Kurian V. J., and Zakaria I. (2006). Flexural behaviour of reinforced lightweight\u003c/li\u003e\n \u003cli\u003eOPS concrete beams. In: 9th International conference on concrete engineering and technology, Malaysia; 2006. p. 244\u0026ndash;252.\u003c/li\u003e\n \u003cli\u003eTeo, D.C.L. Mannan M. A., Kurian V. J. (2009). Production of lightweight concrete using oil palm shell\u003c/li\u003e\n \u003cli\u003e(OPS) aggregates. In: 4th International conference on construction materials: performance, innovations and structural implications, Nagoya, Japan; 2009. p. 661\u0026ndash;6.\u003c/li\u003e\n \u003cli\u003eYang, K.H., Chung, S.H. and Ashour, A.F. (2007). \u0026ldquo;Influence of section depth on the structural behaviour of reinforced concrete continuous deep beams\u0026rdquo;, Mag. Concrete Res., 59(8), 575-586.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"discover-civil-engineering","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Civil Engineering](https://www.springer.com/journal/44290)","snPcode":"44290","submissionUrl":"https://submission.nature.com/new-submission/44290","title":"Discover Civil Engineering","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Palm kernel shell, Deep beams, Ductility ratio, Shear strength, Normal concrete weight","lastPublishedDoi":"10.21203/rs.3.rs-7376026/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7376026/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study investigates the influence of palm kernel shell (PKS) on the mechanical strength properties of reinforced concrete deep beams. A high strength lightweight concrete of grade 30 was prepared using palm kernel shell as coarse aggregate. Three pairs of deep beams, with and without shear reinforcement, of 150 mm width and 350 mm depth, having shear span-to-effective depth ratios of 1.0, 1.5 and 2.0, were prepared for the PKS reinforced concrete deep beams. The beams were cured for 7, 14, 21, and 28 days and tested for ductility and shear strength under three-point loading. The experimental results showed comparatively that the average ductility ratio of the PKS concrete deep beams without shear reinforcement was 1.6 times that of the normal weight concrete (NWC) whilst for the beams with vertical shear reinforcement, the ductility ratio was 1.3 times that of the NWC, showing superiority of palm kernel shell concrete (PKSC) over NWC in terms of ductility. Also, the normalized shear strength of the PKSC deep beams was found to be higher than the NWC samples at all a/d ratios. It was concluded that PKSC deep beams exhibit higher ductility and normalized shear strength characteristics than NWC deep beams and hence can be considered in high-rise buildings as transfer girders especially in earthquake-prone zones.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e","manuscriptTitle":"The Influence of Palm Kernel Shell on the Mechanical Strength Properties of Reinforced Concrete Deep Beams","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-20 17:13:46","doi":"10.21203/rs.3.rs-7376026/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-10-27T09:46:27+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-21T10:51:31+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-19T16:18:40+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-18T18:18:08+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-16T10:43:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"79871373839737721980649039494467573158","date":"2025-10-13T01:17:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"266440870748051307964071255340952962365","date":"2025-10-12T12:43:16+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-11T07:38:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"223662735043832590895520746268712533879","date":"2025-10-10T17:38:36+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-08T21:18:57+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"319178888864881049277362526087273192281","date":"2025-10-07T16:04:43+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"296268496052116037385863017134705923600","date":"2025-10-07T14:56:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"291358325877346554400968498863381968193","date":"2025-10-07T14:30:13+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-07T12:34:31+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-09-28T18:08:06+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-09-24T07:51:13+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-09-15T14:59:12+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Civil Engineering","date":"2025-09-15T14:54:18+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-civil-engineering","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Civil Engineering](https://www.springer.com/journal/44290)","snPcode":"44290","submissionUrl":"https://submission.nature.com/new-submission/44290","title":"Discover Civil Engineering","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d17f9bdf-5e11-4858-a07d-2b15c32b9dbd","owner":[],"postedDate":"October 20th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-03-05T10:24:33+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-20 17:13:46","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7376026","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7376026","identity":"rs-7376026","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}