Mechanical Properties of Alkali Activated Slag Binder-based Concrete Exposed to Elevated Temperature

Mechanical Properties of Alkali Activated Slag Binder-based Concrete Exposed to Elevated Temperature | 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 Mechanical Properties of Alkali Activated Slag Binder-based Concrete Exposed to Elevated Temperature Rajesh Kumar Paswan, Pramod Kumar, Virendra Kumar This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5017589/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Fire is a catastrophic event that significantly threatens structures. As a fire progresses, the strength of concrete deteriorates over time due to the high temperatures. Understanding how the concrete's strength diminishes under high temperatures. The present study is motivated by focusing on how alkali-activated concrete responds to elevated temperatures.There is a growing trend of using ground granulated blast furnace slag (GGBFS) as a constituent material in both normal strength and high-performance concrete. When combined with sodium hydroxide and sodium sulphate powder as activators, this material forms Alkali-activated Concrete(AAC). This research paper investigates the impact of high temperatures on the compressive strength, split tensile strength, and flexural strength of AAS concrete. Test specimens were subjected to temperatures of 100°C, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C and 800°C.The research indicates that AACperforms better than regular binder concrete, making it a potentially better alternative. GGBFS Elevated Temperatures CompressiveStrength Split TensileStrength Flexural Strength Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 1. Introduction Concrete is widely employed in construction and civil engineering due to its flexibility, long-lasting nature, and ability to withstand fire(Amran et al., 2022 ). The demand for concrete as a construction material continues to rise steadily. Consequently, ordinary Portland cement (OPC) production increased from 1.5 billion tons in 1995 to a staggering 2.5 billion tons in 2015 (Hammad et al., 2021 ). According to current global projections, this figure could potentially increase by an additional 25% over the next decade, exacerbating the imminent scarcity of limestone within the next 25–50 years (Naik, 2008 ). To address this issue, extensive research has been conducted for decades on replacing cement with alternative industrial by-products with high alumina and silica, known as aluminosilicates. Recently, this approach has gained significant popularity due to the growing interest in reducing the environmental impact of cement production. Aluminosilicates, which serve as common alternatives to OPC, contain substantial quantities of silicon oxide (SiO 2 ) and aluminum oxide (Al 2 O 3 ) (Yang & Song, 2009 ). Although Alkali-activated Concrete(AAC) exhibits certain drawbacks compared to OPC concrete, such as increased carbonation and shrinkage, it offers numerous advantages to the construction industry regarding durability and rapid strength development. Notably, the rapid strength development of AAC makes it a viable substitute for OPC in deep-water oil well cementing applications. The utilization of AAC concrete presents opportunities for reducing environmental impact while still meeting the construction industry's requirements for durability and strength (Jiapei et al., 2018 ). GGBFS isderived by rapidly cooling molten iron slag, a by-product of the iron and steel-making process, using water or steam. This cooling process produces a glassy and granular material, which is subsequently dried and finely ground into a powder. Blast furnace slag is generated when iron ore is combined with coke and subjected to high temperatures ranging from 1350 to 1550°C within a blast furnace.GGBFS serves as an environmentally friendly binding material that helps reduce CO 2 emissions. It is more durable than OPC and other pozzolanic materials. GGBFS can be used as a cementitious binder and admixture to produce traditional, high-performance concrete. Its inclusion enhances workability, durability, and long-term strength (Lee et al., 2006 ). Previous experimental studies have shown that GGBFS concrete exhibits a more uniform and optimized distribution of pore sizes, resulting in denser and more durable concrete structures (Chithambaram et al., 2019 ; Singh et al., 2023). Moreover, GGBFS concrete demonstrates early strength development during high-temperature curing due to its temperature-dependent characteristics (Kishore, 2023 ). Consequently, GGBFS is suitable for manufacturing precast concrete subjected to high-temperature curing. However, GGBFS possesses latent hydraulic properties and requires an alkaline activator to trigger its cementitious characteristics in producingAAC concrete (Amer et al., 2021 ). Introducing an alkaline activator initiates a reaction between a strongly alkaline liquid and solid aluminum silicate material, forming N-A-S-H gel (Xu et al., 2021 ).Like the cement hydrate product C-S-H gel, this gel is known as an alkali-activated product (Sanni &Khadiranaikar, 2012 ). This paper explores several studies concerning alternative materials for replacing Portland Slag Cement (PSC), specifically focusing on GGBFS. It is widely recognized that new binders are required to improve cement's environmental and durability performance. An alkali-activated (AA) binder was developed by combining GGBFS with alkali metal hydroxide and metal sulphate, serving as an activator. When mixed with slag, this activator produces a novel binder material that exhibits properties like conventional cement binders.Alumino-silicate materials, namely GGBS, are mixed with an alkali solution during the geopolymer preparation process. This mixture forms AlO 4 and SiO 4 tetrahedral units(Lecomte et al., 2006 ), which are interconnected by shared oxygen atoms, resulting in polymeric structures known as poly(sialates), poly(sialate–siloxo), or poly(sialate–disiloxo), depending on the SiO 2 /Al 2 O 3 ratio. The impact of variables such as Si/Al, SiO 2 /Na 2 O, and Al 2 O 3 /Na 2 O on the system has been addressed in previous research (Komljenović et al, 2010 ; Ryu et al., 2013 ). The formation of polymeric precursors (-SiO 4 –AlO 4 –, -SiO 4 –AlO 4 –SiO 4 –, or -SiO 4 –AlO 4 –SiO 4 –SiO 4 –) occurs through the sharing of all oxygen atoms between two tetrahedral units, accompanied by the release of water molecules (Davidovits, 2013 ). The connection between the tetrahedral frameworks is established through long-range covalent bonds. Geopolymer exhibits several advantages, including high compressive strength, fire resistance, low shrinkage, and excellent acid resistance. Temperature is a significant factor that has a notable impact on the strength of concrete (Ozbayrak et al., 2023). Concrete can be exposed to elevated temperatures in both controlled and uncontrolled fire scenarios. Concrete subjected to high temperatures directly affects its compressive, tensile, and flexural strength (Zhang et al., 2016 ). One of the key reasons for strength loss in concrete at elevated temperatures is the development of cracks between the cement paste and aggregate due to thermal incompatibility between these components. However, normal-strength concrete generally exhibits better fire resistance than high-strength concrete (Phan & Phan, 1996 ).Exposure to elevated temperatures causes significant changes in the concrete matrix's chemical composition and physical structure (Yasaswini& Rao, 2020 ). High temperature is a crucial factor in the physical deterioration processes that impact the stability and durability of concrete structures (Hertz, 2005 ). The behaviour of concrete under high-temperature conditions is greatly influenced by material properties, including the characteristics of the aggregate, cement paste, and the bond between the aggregate and cement paste (Arioz, 2007 ). Understanding how concrete structures and construction materials behave under elevated temperatures and fire conditions is of utmost importance for designers and researchers worldwide, as it directly affects the safety of human lives. Nevertheless, examining the high-temperature performance of alkali-activated GGBFS as a complete replacement for cement has been limited in previous studies. This study aims to fill this research gap in the existing literature. The present study demonstrates through experimental investigations that the AAC binder exhibits superior properties and is environmentally friendly, making it a promising substitute for OPC in construction and repair projects. However, these conclusions are solely based on testing conducted at ambient temperature.Understanding AAC's mechanical behavior under elevated temperatures is crucial. Therefore, a series of mechanical tests were carried out to examine the impact of elevated temperatures on Alkali Activated Slag Binder concrete. This study prepared concrete specimens using 100% Alkali-activated slag binder, comprising 94% GGBFS and 6% alkali activator and subjected to heating up to 800 ℃. Furthermore, a comparative benchmark test was performed using PSC and OPC43 concrete for reference.By investigating the mechanical properties of AAC concrete under elevated temperatures, this study aims to provide insights into its performance in challenging thermal conditions. 2. Experimental program 2.1 Materials 2.1.1 Cement The investigation utilized PSC from Lafarge Co. due to its favorable characteristics, including low heat of hydration, making it well-suited for mass construction. The physical properties of PSC were examined and are provided as follows: The fineness modulus, normal consistency, specific gravity, initial setting time, and final setting time of the binder were determined to be 3.0%, 33%, 3.06, 68 minutes, and 300 minutes, respectively (Table 1 ). OPC of grade 43 is also used as a benchmark material for comparative purposes. The physical properties of OPC43 were measured as follows: The fineness modulus, normal consistency, specific gravity, initial setting time, and final setting time of the binder were determined to be 4%, 30%, 3.1, 48 minutes, and 262 minutes, respectively(Table 1 ). Table 1 Physical properties of conventional cement PhysicalRequirements PSC OPC43 SpecificGravity 3.0 4.0 StandardConsistency 33% 30% SoundnessLe-Chatelier(mm) 3.06 3.1 Setting timeinitial(min) 68 48 Setting timefinal(min) 300 262 2.1.2 GGBFS The binder used in the study was GGBFS, which was obtained as industrial waste from Tata Steel Ltd. in Jamshedpur. This GGBFS complied with the IS: 12089 (1987). It is composed of various elements, including Lime (CaO), Silica (SiO 2 ), Alumina (Al 2 O 3 ), Magnesium oxide (MgO), Sulphur (S), Glass content, Ferric Oxide (Fe 2 O 3 ), Loss on Ignition K 2 O. The chemical composition details of the binder materials utilized in the study are presented in Table 2 . Additionally, the dimensional modulus, specific gravity, and bulk density in the compacted state of the GGBFS were determined to be 2.83, 2.59, and 1670 kg/m 3 , respectively. Table 2 Chemical composition of different binders Compound GGBFS PSC OPC43 CaO 61.5 63.69 62.49 SiO 2 18.34 21.21 20.27 Al 2 O 3 9.76 5.54 5.32 MgO 6.26 2.93 4.46 Fe 2 O 3 1.32 3.11 3.16 SO 3 0.83 2.63 3.53 TiO 2 0.74 - - K 2 O 0.36 0.71 0.65 MnO 0.15 - - Na 2 O 0.14 0.18 0.12 P 2 O 5 0.07 - - CeO 2 0.06 - - SrO 0.06 - - 2.1.3 AlkaliActivator In this study, an activator was employed, which consisted of a mixture of metal hydroxides (MOH) and A 2 B. This activator is alkaline, contributing to a combined pH of approximately 13. A 2 B, a significant constituent of the activator, is primarily composed of SO 3 and Na 2 O. For a more detailed understanding of the composition and characteristics of A 2 B, please refer to Table 3 , which provides a comprehensive description of this component. The specific properties of the activator, such as its alkalinity and major components, play a crucial role in its role as an activator in the study. Table 3 Chemical composition of alkali activator (A 2 B) Compound A2B% CaO 0.08 MgO 0.12 Fe2O3 0.02 SO3 80.3 K2O 0.19 MnO 0.02 Na2O 16.36 P2O5 0.02 2.1.4 Fine aggregate and coarse aggregate The study utilized local fine-grained aggregates sourced from the Kharkai River, which meet the requirements specified in the IS 383:2016 standard for zone II. These aggregates exhibit the following characteristics: a fineness modulus of 2.83, specific gravity of 2.59, free moisture content of 0.2%, water absorption of 0.8%, bulking of sand of 3%, and a bulk density of 1560 kg per cubic meter in the compacted state.Additionally, coarse aggregates obtained from Jamshedpur, Jharkhand, were used in the experiment. The coarse aggregates were of two sizes: 20 mm and 12.5 mm. The 20 mm size coarse aggregate exhibited a fineness modulus of 6.81, specific gravity of 2.83, and water absorption of 0.35%. The 12.5 mm size coarse aggregate had a fineness modulus of 5.8, specific gravity of 2.54, and water absorption of 0.20%. These properties of the coarse aggregates are essential in determining their suitability for use in the study. 2.2 Casting and curing To conduct the experiment, the alkali-activated binder was prepared using 94% GGBFS 3% metal hydroxides, and 3% metal sulphates as alkali activators. Fine aggregate was sourced from Tata Steel Pvt. Ltd., while the coarse aggregate was obtained from the Kharkai river bed and locally available rock stone aggregate. All materials used in the experiment were found to comply with the IS 383–1970 standard.The activator solution was prepared by mixing the activators with water and stirring for 10 minutes to achieve a homogeneous consistency. The alkali binder, sand, and aggregate were then mixed according to the IS: 10262 (2009) specifications. The proportions of the concrete mix are listed in Table 4 . Table 4 Mix design proportions of different constituents S. No. Ingredients Mass of materials (kg) Mix proportion 1 Binder content 352.98 1:1.9:3.38 2 Fine aggregate 672.39 3 Coarse aggregate 1194.14 4 Water 173 The mix was used to cast 26 specimens, including size 150 X 150 X 150 mm cubes, cylindrical specimens with a diameter of 150 mm and length of 300 mm, and prism specimens measuring 500 X 100 X 100 mm. After being kept in the moulds for 24 hours, the specimens were subjected to water-curing conditions. The concrete mixtures were designed based on the absolute volume method for M25 grade concrete, following the guidelines of IS: 10262 (2009). The materials were proportioned by weight, resulting in a final mix proportion of 1:1.9:3.38, with a fixed water-cement ratio of 0.49. The desired workability was achieved by targeting a slump value within the 90 ± 10 mm range. 2.3 Testing The workability of concrete refers to its ability to be easily mixed and achieve a uniform consistency. It is primarily influenced by the water-cement ratio, with higher ratios resulting in increased workability. The workability was evaluated using the slump cone test (100 X 200 X 300 mm) according to IS: 1199 (1959). This test was performed batch-to-batch to ensure consistent concrete quality during casting. The compressive strength of concrete represents the maximum uniaxial stress it can withstand before failure. The compressive strength of the cube specimens was tested using a universal testing machine with a capacity of 3,000 kN, and the loading ratewas 140 kg/cm 2 /min. It is determined by dividing the failure load by the cross-sectional area resisting the load, which is reported in N/mm 2 . Compressive strength tests were conducted on 150 mm cube specimens following IS:516–1959, using a digital compression testing machine after curing for 3, 7, and 28 days.Tensile strength is a crucial property of concrete, although it is inherently weak in tension and prone to cracking under tensile forces. The split tensile strength (T) was calculated using Eq. 1 . 1 Where; P = Applied load D = Diameter of the cylinder L = Length of the cylinder The split tensile strength test was performed on (300 X 150) mm cylinder specimens according to IS:516–1959. The split tensile of the cylinders specimens were tested using a universal testing machine with a capacity of 3,000 kN, and the loading rates for the split tensile strength test were 1.2–2.4 N/mm 2 /min. Flexural strength measures a concrete’s ability to withstand bending caused by factors such as temperature changes. It was determined using (100 X 100 X 500) mm beam specimens under two-point loading, following IS:516–1959. The flexural strength was calculated using Eq. 2 , considering a shear span (a) less than 110 mm. $$\:{F}_{b}=\frac{PL}{b{d}^{2}}$$ 2 To investigate the effect of elevated temperatures, the specimens were heated in an electric muffle furnace at temperatures ranging from 100 o C to 800℃. The heating rate was set at 10°C/minute until the desired temperature was reached, and then it was maintained for 4 hours before allowing the specimens to cool naturally to room temperature. 3. Results and discussions 3.1 Compressive strength of mortar on ambient temperature The results displayed in Fig. 1 depict the compressive strength of mortar samples made with GGBFS, PSC, and OPC43. The compressive strength values at the curing period of 28 days for PSC, GGBFS, and OPC43 mortar were recorded as 33.92 N/mm², 35.39 N/mm², and 43.79. N/mm², respectively. The study examined the compressive strength of GGBFS mortar(Chithambaram et al., 2019 ) and compared it with two other types of mortar: PSC and OPC 43. Upon analyzing the results, it was found that GGBFS mortar demonstrated distinct compressive strength characteristics.The compressive strength of GGBFS mortar was approximately 4.33% higher than PSC. This indicates that GGBFS mortar outperforms PSC in terms of compressive strength, suggesting it could be a favorable option in certain applications requiring higher strength.On the other hand, when compared to OPC43, the compressive strength of GGBFS mortar was 19.18% lower. This substantial difference indicates that OPC43 still maintains a significant advantage over GGBFS mortar regarding compressive strength. The findings suggest that regarding compressive strength, GGBFS mortar falls between PSC and OPC43. It exhibits a slight advantage over PSC but falls significantly short of OPC43. 3.2 Compressive strength of concrete on ambient and elevated temperature A comparison was conducted to evaluate the compressive strength of alkali-activated slag concrete with PSC concrete and OPC43 concrete. Figures 2 , 3 , and 4 presented the compressive strength results under ambient and elevated temperatures, respectively. After 28 days of curing, the compressive strength values were recorded as 29.11 N/mm 2 , 32.54 N/mm 2 , and 36.54 N/mm 2 for PSC, GGBFS, and OPC43 concrete. Figure 2 revealed that GGBFS concrete achieved a significantly higher compressive strength than PSC concrete, with approximately 11.78% improvement at the age of 28 days. Conversely, compared to OPC43 concrete, GGBFS concrete exhibited a lower compressive strength, with a reduction of approximately 10.95% at 28 days. The compressive strength of alkali-activated slag concrete consistently surpassed that of PSC concrete. However, when compared to OPC43 concrete, alkali-activated slag concrete demonstrated lower compressive strength values.The results indicate that GGBFS concrete outperformed PSC concrete in terms of compressive strength, exhibiting higher values. However, when compared to OPC43 concrete, GGBFS concrete displayed lower compressive strength. The study investigated the compressive strength of different binder concretes under ambient conditions and then subjected them to testing at elevated temperatures (Figs. 3 and 4 ). The results in Fig. 3 indicate the changes in compressive strength as the temperature was raised from ambient to 100 o C(Shen and Xu, 2019 ; Pratap and Kumar, 2024 ).As the temperature increased from ambient to 100 o C (Fig. 3 ), the compressive strength of PSC, GGBFS, and OPC43 concrete showed varying degrees of improvement(Tayeh et al., 2021 ). Specifically, PSC concrete experienced an 11.06% increase in compressive strength, while GGBFS and OPC43 concrete demonstrated smaller improvements of 1.09% and 5.23%, respectively. As the temperatures continued to rise beyond 100 o C, the compressive strength of the concretes exhibited a reduction. For PSC concrete, the decrease in compressive strength ranged from 10.54% to as much as 78.16%, indicating a significant loss in strength. GGBFS concrete experienced a compressive strength reduction of 3.84–72.43%, while OPC43 concrete showed the most substantial decline, ranging from 3.17% to a remarkable 96.69% (Fig. 4 ). 3.3 Split tensile strength of concrete on ambient and elevated temperature This study compared the split tensile strength of alkali-activated slag concrete with that of PSC concrete and OPC43 concrete. Figures 5 , 6 , and 7 presented the results for split tensile strength under ambient and elevated temperatures, respectively. After a curing period of 28 days, the split tensile strength values were measured as 4.7 N/mm 2 , 4.9 N/mm 2 , and 5.4 N/mm 2 for PSC, GGBFS, and OPC43 concrete, respectively.From Fig. 5 , it was evident that GGBFS concrete exhibited significantly higher split tensile strength than PSC concrete, with an approximate 4.26% improvement at the age of 28 days. In contrast, compared to OPC43 concrete, GGBFS concrete displayed lower split tensile strength, showing a reduction of approximately 15.52% at the same age. Consistently, alkali-activated slag concrete demonstrated higher split tensile strength values than PSC concrete across the various test conditions. However, when compared to OPC43 concrete, alkali-activated slag concrete exhibited lower split tensile strength values.The study aimed to analyze the split tensile strength of different binder concretes under both ambient and elevated temperature conditions (Figs. 6 and 7 ). As the temperature increased from ambient, the split tensile strength of PSC, GGBFS, and OPC43 concrete began to decrease (Fig. 6 )(Husem, 2006 ). As the elevated temperatures continued to rise beyond the ambient level, the split tensile strength of all concretes exhibited a significant reduction. For PSC concrete, the decrease in split tensile strength ranged from 10.64% to as much as 76.59%, indicating a substantial loss in its ability to withstand tensile forces. Similarly, GGBFS concrete experienced a split tensile strength reduction of 8.20–73.47%, showing its vulnerability to elevated temperatures(Tayeh et al., 2021 ).The most substantial decline was observed in OPC43 concrete, with its split tensile strength dropping from 13.79% to an astounding 75.86% (Fig. 7 ). These findings indicate that OPC43 concrete is highly sensitive to increasing temperatures and tends to suffer a severe reduction in its split tensile strength as it rises. The study's results highlight the negative impact of elevated temperatures on the split tensile strength of different binder concretes. Understanding this behaviour is crucial for selecting appropriate concrete types in applications where the material may be exposed to elevated temperatures, as it helps ensure the structural integrity and safety of concrete structures under varying environmental conditions. 3.4 Flexural strength of concrete on ambient and elevated temperature One of the focuses of the present study is to compare the flexural strength of alkali-activated slag concrete with that of PSC concrete and OPC 43 concrete. Figures 8 , 9 , and 10 presented the results for flexural strength under ambient and elevated temperature conditions, respectively. After a curing period of 28 days, the flexural strength values were recorded as 4.7 MPa, 4.9 MPa, and 5.4 MPa for PSC, GGBFS, and OPC 43 concrete, respectively. Figure 8 indicated that GGBFS concrete exhibited significantly higher flexural strength than PSC concrete, with an approximate 8.51% improvement at 28 days. This suggests that GGBFS concrete demonstrates enhanced resistance to bending forces compared to PSC concrete. However, compared to OPC 43 concrete, GGBFS concrete displayed lower flexural strength, with a reduction of approximately 12.07% at the same age. This implies that OPC43 concrete outperforms GGBFS concrete in flexural strength, demonstrating a higher ability to withstand bending stresses. The findings indicate that GGBFS concrete performs better than PSC concrete in flexural strength, exhibiting higher values. However, compared to OPC43 concrete, GGBFS concrete showed lower flexural strength. This study section examines the flexural strength of different binder concretes under ambient and elevated temperature conditions, as illustrated in Figs. 9 and 10 . As the temperature increased from the ambient level, the flexural strength of PSC, GGBFS, and OPC43 concrete began to decline. As the elevated temperatures continued to rise beyond the ambient level, the flexural strength of all concrete types exhibited a significant reduction (Fig. 9 ). PSC concrete experienced a decrease in flexural strength ranging from 12.76% to an alarming 85.10%, indicating a substantial loss in its ability to withstand bending forces. Similarly, GGBFS concrete demonstrated a flexural strength reduction(Yasaswini& Rao, 2020 ) of 3.92–80.27%, indicating its susceptibility to elevated temperatures. The most substantial decline was observed in OPC43 concrete, with its flexural strength decreasing from 12.07% to a remarkable 84.48% (Fig. 10 ). These findings emphasize that OPC43 (Husem, 2006 )concrete is highly sensitive to increasing temperatures and undergoes a significant reduction in flexural strength as the temperature rises. The study highlights the impact of elevated temperatures on the flexural strength of different binder concretes. It indicates that as temperatures increase beyond ambient, all concrete types experience a decrease in flexural strength. In Fig. 11 , the researchers investigated the colour change of concrete when exposed to elevated temperatures. They examined the external surface of the concrete element and focused on areas where visible aggregates were present. The observed colour changes are depicted in Fig. 8 . The researchers found that the colour of the concrete varied depending on the temperature it was subjected to. Between 100–300°C, the concrete transformed from grey to whitish grey. At temperatures ranging from 400–600°C, it turned reddish. Finally, when exposed to 800°C, the concrete became buff. These colour changes can be attributed to two main factors: the gradual removal of water and dehydration of the cement paste and the transformations occurring within the aggregate.As the concrete is exposed to elevated temperatures, the heat causes the moisture present in the cement paste to evaporate gradually. This process of water removal and dehydration leads tochanges in the colour of the concrete.Additionally, the aggregates within the concrete also undergo transformations under high temperatures. The siliceous aggregate's specific chemical and mineral composition plays a role in the observed colour changes. The interaction between the aggregate and the heat alters the aggregate's physical and chemical properties, which, in turn, affects the colour of the concrete. 4. Mass loss of different specimens Concrete samples were subjected to oven drying, causing them to lose mass due to water evaporation or other factors. The percentage mass loss of mortar, concrete cubes, cylinders, and prisms can be observed in Figs. 12 , 13 , 14 , and 15 , respectively. This experiment likely aimed to study how different concrete shapes and compositions react to drying, providing valuable insights into their durability and water-retention capabilities. Figure 12 illustrates that the mass loss of mortar specimens rises with higher temperatures. The percentage mass loss varies for different cement types: PSC shows a range of 2.4–9.9%, GGBFS exhibits 2.1–9.4% loss, and OPC 43 has a range of 1.1–8.2% loss. These findings suggest that as the temperature increases, all three binder types experience increased mass loss, with PSC demonstrating the highest susceptibility to loss, followed by GGBFS and OPC43. Understanding these variations is vital for designing and selecting appropriate cement types for different temperature conditions in construction projects. Figure 13 depicts the relationship between temperature and mass loss in concrete cube specimens. As the temperature rises, the mass loss of the specimens also increases. The percentage mass loss varies among different cement types: PSC shows a range of 0.87–8.8%, GGBFS exhibits a range of 0.69–7.9% loss, and OPC 43 has a range of 0.55–7.4% loss. These findings indicate that PSC is the most susceptible to mass loss at higher temperatures, followed by GGBFS and OPC 43. Figure 14 illustrates the relationship between temperature and mass loss in concrete cylinder specimens. With an increase in temperature, the specimens experience higher mass loss. The percentage mass loss varies across different cement types: PSC exhibits a range of 0.85–6.3% loss, GGBFS shows a range of 0.78–5.9% loss, and OPC43 demonstrates a range of 0.56–5.5% loss. These results indicate that PSC is the most vulnerable to mass loss at elevated temperatures, followed by GGBFS and OPC43. Figure 15 displays the correlation between temperature and mass loss in concrete prism specimens. As the temperature increases, the specimens undergo greater mass loss. The percentage mass loss differs for various cement types: PSC shows a range of 0.45–5.4% loss, GGBFS exhibits a range of 0.35–5.1% loss, and OPC43 demonstrates a range of 0.22–4.2% loss. 5. Conclusions In conclusion, compressive, split, and flexure strengths of geopolymer concreteunder ambient and elevated temperatures have been thoroughly investigated and analyzed. The findings from various studies highlight the response and behaviour of geopolymer concrete when subjected to high temperatures, providing valuable insights for the construction industry.Extensive research and analysis have been conducted on polymer concrete under ambient and elevated temperature conditions. The primary objective of these studies is to gain valuable insights into the behaviour, properties, and overall performance of polymer concrete when subjected to varying temperature levels. The key findings and conclusions derived from these investigations are outlined below: In conclusion, the analysis of the compressive strength values of GGBFS mortar at different curing periods of 28 days revealed that its strength ishigher compared to both PSC and lower than the OPC43. Specifically, the compressive strength of GGBFS mortar was approximately 4.33% higher than PSC and 19.18% lower than OPC43. These findings suggest that GGBFS mortar can be a viable alternative with improved strength characteristics compared to PSC, albeit still falling short of the strength exhibited by OPC43. After 28 days of curing, compressive strength values were 29.11 N/mm 2 for PSC, 32.54 N/mm 2 for GGBFS, and 36.54 N/mm 2 for OPC43 concrete. GGBFS achieved 11.78% higher strength than PSC and 10.95% lower compressive strength than OPC43. At 100°C, the compressive strength of PSC, GGBFS, and OPC43 simproved. However, at temperatures beyond 100°C, all concretes weakened significantly. PSC reduced by 10.54–78.16%, GGBFS by 3.84–72.43%, and OPC43 by 3.17% to a substantial 96.69%. Higher temperatures negatively impacted compressive strength across all concrete types. In conclusion, GGBFS concrete showed significantly higher split tensile strength than PSC concrete after 28 days, with a 4.26% improvement. However, it exhibited lower split tensile strength than OPC43 concrete, with a reduction of approximately 15.52%. As temperatures increased, all concrete experienced notable decreases in split tensile strength, with PSC, GGBFS, and OPC43 showing reductions ranging from 10.64–76.59%, 8.20–73.47%, and 13.79–75.86%, respectively, indicating their susceptibility to elevated temperatures. after 28 days of curing, the flexural strength values were 4.7 N/mm 2 for PSC, 4.9 N/mm 2 for GGBFS, and 5.4 N/mm 2 for OPC43 concrete. GGBFS concrete exhibited significantly higher flexural strength than PSC concrete, with an approximate 8.51% improvement. However, GGBFS concrete showed lower flexural strength than OPC43 concrete, with a reduction of approximately 12.07%. As temperatures increased, all concrete types experienced a decline in flexural strength. PSC concrete showed a significant decrease ranging from 12.76–85.10%, GGBFS concrete exhibited a reduction of 3.92–80.27%, and OPC43 concrete displayed the most substantial decline from 12.07–84.48%. The evaluation of test specimens at elevated temperatures demonstrated that only the residual compressive strength increased as the temperature rose from ambient to 100°C, followed by a subsequent decrease. However, the residual split tensile and flexural strength immediately declined upon increasing the temperature from ambient conditions. The evaluation of mass loss in different test samples revealed distinct patterns. The PSC sample demonstrated higher mass loss, indicating a greater weight reduction than the other samples. On the other hand, the OPC43 sample exhibited lesser mass loss, suggesting a relatively lower reduction in weight. The GGBFS sample displayed intermediate mass loss, falling between the levels observed in the PSC and OPC43 samples. These results suggest variations in the susceptibility of the different cement types to undergo mass loss during the evaluation process. The study's conclusion suggests that GGBFS can be considered a favorable replacement for PSC in various construction applications. The research indicates that GGBFS exhibits superior performance compared to PSC, making it a potentially better alternative. However, it is worth noting that GGBFS shows lower results than OPC43 in certain aspects. This calls for further investigation and assessment to understand better the specific scenarios where GGBFS can be optimally utilized and address potential limitations. Additional research will help validate its practical applications in construction projects. Declarations Credit authorship contribution statement Rajesh Kumar Paswan : Methodology, Investigation, Writing - original draft. Pramod Kumar :Writing – review & editing. Virendra Kumar :Investigation, Review & editing, Supervision. Conflict of interest: The authors declare that there is no conflict of interest regarding thepublication of this paper. Funding: None. No funding to declare. Author Contribution A. Rajesh Kumar Paswan: Investigation, Methodology, Visualization, Resources, Writing - review & editing.B. Virendra Kumar: Formal analysis, Conceptualization, Validation, Visualization, Writing- Original draft, Writing - review & editing.T. Pramod Kumar: Methodology, Visualization Acknowledgement The authors would like to thank to the Research and Development division, Tata Steel Ltd., Jamshedpur for the supply of Ground Granulated Blast Furnace Slag (GGBFS). The authors would like to thank the Department of Civil Engineering, R.V.S College of Engineering and Technologuy, Jamshedpur, for providing there research facilities. The authors would also like to thank N. Ramkumar, Ph.D., Director, Navoday Sciences Pvt. Ltd., Chennai for supplying the activator along with the technical input. Data availability: Data will be made available at the request of the corresponding author. References Amran M, Huang SS, Debbarma S, Rashid RS (2022) ,Fire resistance of geopolymer concrete: A critical review. Constr Build Mater 324:126722 Amer I, Kohail M, El-Feky MS, Rashad A, Khalaf MA (2021) ),A review on alkali-activated slag concrete. Ain Shams Eng J 12(2):1475–1499 Arioz O (2007) ,Effects of elevated temperatures on properties of concrete. Fire Saf J 42(8):516–522 Chithambaram SJ, Kumar S, Prasad MM (2019) ,Thermo-mechanical characteristics of geopolymer mortar. Constr Build Mater 213:100–108 Davidovits J (2013) ,Geopolymer cement. A review. Geopolymer Inst Tech papers 21:1–11 Hammad N, El-Nemr A, Hasan HED (2021) ,The performance of fibreGGBS-based alkali-activated concrete. J Building Eng 42:102464 Hertz KD (2005) ,Concrete strength for fire safety design. Magazine Concrete Res 57(8):445–453 Husem M (2006) ,The effects of high temperature on compressive and flexural strengths of ordinary and high-performance concrete. Fire Saf J 41(2):155–163 IS 12089 (1987) Specification for granulated slag for the manufacturing of Portland cement. Bureau of Indian Standard , New Delhi IS 10262 (2009) Guidelines for concrete mix design proportioning. Bureau of Indian Standard, New Delhi IS 1199 (1959) Methods of sampling and analysis of concrete. Bureau of Indian Standard, New Delhi Jiapei D, Yuhuan B, Xuechao C, Zhonghou S, Baojiang S (2018) ,Utilization of alkali-activated slag-based composite in a deepwater oil well cementing. Constr Build Mater 186:114–122 Kishore K (2023) Geopolymer concrete and its strength influencing variables, Materials Today: Proceedings , 80, 1434–1441 Komljenović M, Baščarević Z, Bradić V (2010) ,Mechanical and microstructural properties of alkali-activated fly ash geopolymers. J Hazard Mater 181(1–3):35–42 Pratap B, Kumar P (2024) ,Effect of the elevated temperature on the mechanical properties of geopolymer concrete using fly ash and ground granulated blast slag. J Struct Fire Eng 15(3):409–425 Lecomte I, Henrist C, Liégeois M, Maseri F, Rulmont A, Cloots R (2006) ,Micro-structural comparison between geopolymers, alkali-activated slag cement and Portland cement. J Eur Ceram Soc 26(16):3789–3797 Lee KM, Lee HK, Lee SH, Kim GY (2006) Autogenous shrinkage of concrete containing granulated blast-furnace slag. Cem Concr Res 36(7):1279–1285 Naik TR (2008) Sustainability of concrete construction. Pract Periodical Struct Des Constr 13(2):98–103 Özbayrak A, Kucukgoncu H, Aslanbay HH, Aslanbay YG, Atas O (2023) ,Comprehensive experimental analysis of the effects of elevated temperatures in geopolymer concretes with variable alkali activator ratios. J Building Eng 68:106108 Phan LT, Phan LT (1996) Fire performance of high-strength concrete: a report of the state-of-the-art (Vol. 105). National Institute of Standards and Technology, Gaithersburg, MD Ryu GS, Lee YB, Koh KT, Chung YS (2013) ,The mechanical properties of fly ash-based geopolymer concrete with alkaline activators. Constr Build Mater 47:409–418 Singh P, Prasad B, Kumar V (2024) ,Influence of elevated temperature on compressive strength of LD slag aggregate concrete. J Struct Fire Eng 15(1):76–90 Sanni SH, Khadiranaikar RB (2012) Performance of geopolymer concrete under severe environmental conditions. Int J Civil Struct Eng 3(2):396–407 Shen J, Xu Q (2019) ,Effect of elevated temperatures on compressive strength of concrete. Constr Build Mater 229:116846 Tayeh BA, Zeyad AM, Agwa IS, Amin M (2021) ,Effect of elevated temperatures on mechanical properties of lightweight geopolymer concrete. Case Stud Constr Mater 15:e00673 Xu LY, Alrefaei Y, Wang YS, Dai JG (2021) ,Recent advances in molecular dynamics simulation of the NASH geopolymer system: modeling, structural analysis, and dynamics. Constr Build Mater 276:122196 Yang KH, Song JK (2009) ,Workability loss and compressive strength development of cementless mortars activated by combination of sodium silicate and sodium hydroxide. J Mater Civ Eng 21(3):119–127 Yasaswini K, Rao AV (2020) Behaviour of geopolymer concrete at elevated temperature, Materials Today: Proceedings , 33, 239–244 Zhang HY, Kodur V, Wu B, Cao L, Wang F (2016) ,Thermal behavior and mechanical properties of geopolymer mortar after exposure to elevated temperatures. Constr Build Mater 109:17–24 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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. 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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-5017589","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":357508761,"identity":"9523c01a-ceb6-4e9a-9305-3903f88dd532","order_by":0,"name":"Rajesh Kumar Paswan","email":"","orcid":"","institution":"R.V.S College of Engineering and Technology Jamshedpur","correspondingAuthor":false,"prefix":"","firstName":"Rajesh","middleName":"Kumar","lastName":"Paswan","suffix":""},{"id":357508762,"identity":"9fd963c3-eebb-4c37-b57a-059d3822d6ff","order_by":1,"name":"Pramod Kumar","email":"","orcid":"","institution":"Mohan Babu University (SVEC) Tirupati","correspondingAuthor":false,"prefix":"","firstName":"Pramod","middleName":"","lastName":"Kumar","suffix":""},{"id":357508763,"identity":"46a0c0fb-38fd-4af3-86af-e7b759ca5912","order_by":2,"name":"Virendra Kumar","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBElEQVRIiWNgGAWjYBACCSTKgIHxz385EOvAA+K1NDAbg7UkENbCANeS2ABi4tMiOSM78XNlm0U+v3Tztg8/d7Clzw87/BBoi52cbgN2LdISuZslz7ZJWM6cc6x4Zu8ZntyNt9MMgFqSjc0OYNciJ5G7QbLhjISBwY0cYwYeNoncjbMTQFoOJG7DrWXzT5AWe6AWxj9sBumGs9M/4NUCdNg2yYYKoC0SOcbMvG0JCfLSOfhtkex5u80SpEXiRloxs8yZA4YbpHMKDiQY4PaLxPHczTcbDOoM+Gckb2Z8U3FAXn52+uYPHyrs5HBpwQQGYJUGxCoHAfkGUlSPglEwCkbBSAAAmW1fE0+1ApgAAAAASUVORK5CYII=","orcid":"","institution":"National Institute of Technology Jamshedpur","correspondingAuthor":true,"prefix":"","firstName":"Virendra","middleName":"","lastName":"Kumar","suffix":""}],"badges":[],"createdAt":"2024-09-02 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2","display":"","copyAsset":false,"role":"figure","size":126078,"visible":true,"origin":"","legend":"\u003cp\u003eCompressivestrengthof concrete consisting of different binders at 28 days\u003c/p\u003e","description":"","filename":"Picture2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/00c7baa471e66914839fbb62.jpg"},{"id":65950190,"identity":"5fbe2a46-393c-4ea1-9709-9eb3396c3c06","added_by":"auto","created_at":"2024-10-04 19:27:55","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":296413,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of temperature on compressive strength variation in concrete with different binders\u003c/p\u003e","description":"","filename":"Picture3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/7cf4cdd82597c8538ed646cb.jpg"},{"id":65950009,"identity":"9de0dbb3-d674-4301-abc5-abe7412fac80","added_by":"auto","created_at":"2024-10-04 19:19:55","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":171378,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of temperature on residual compressive strength variation in concrete with different binders\u003c/p\u003e","description":"","filename":"Picture4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/287c955af7b57e339a41cf15.jpg"},{"id":65950191,"identity":"a7b277d1-f6d3-4348-9475-4b698ff3f373","added_by":"auto","created_at":"2024-10-04 19:27:55","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":200660,"visible":true,"origin":"","legend":"\u003cp\u003eSplit tensile strengthof concrete consisting of different binders at 28 days\u003c/p\u003e","description":"","filename":"Picture5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/dcf526fae2c7edddc8b694eb.jpg"},{"id":65950007,"identity":"f960b0ff-3aad-44b6-90b3-b7a7b0d0dec1","added_by":"auto","created_at":"2024-10-04 19:19:55","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":334194,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of temperature on split tensile strength variation in concrete with different binders\u003c/p\u003e","description":"","filename":"Picture6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/59fcd937c4ca46dbbd48181a.jpg"},{"id":65949955,"identity":"4872a48b-2e9e-4c21-b2f1-83d1e1fcbf24","added_by":"auto","created_at":"2024-10-04 19:11:55","extension":"jpg","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":188289,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of temperature on residual split tensile strength variation in concrete with different binders\u003c/p\u003e","description":"","filename":"Picture7.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/eb1ae75f80707908ee232f7a.jpg"},{"id":65950012,"identity":"97ab5989-3755-49e3-9877-e04c775522ee","added_by":"auto","created_at":"2024-10-04 19:19:56","extension":"jpg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":169266,"visible":true,"origin":"","legend":"\u003cp\u003eFlexural strength of concrete consisting of different binders at 28 days\u003c/p\u003e","description":"","filename":"Picture8.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/ecdbb0efb841c12f749c4fbf.jpg"},{"id":65949967,"identity":"13588756-1056-42a9-bb2f-004f779b774b","added_by":"auto","created_at":"2024-10-04 19:11:56","extension":"jpg","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":331734,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of temperature on flexural strength variation in concrete with different binders\u003c/p\u003e","description":"","filename":"Picture9.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/e0b9cc6c38c73c5467e1a222.jpg"},{"id":65950011,"identity":"6f245dfd-d5c8-4358-8181-ae43c30f53cd","added_by":"auto","created_at":"2024-10-04 19:19:55","extension":"jpg","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":211657,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of temperature on residual flexural strength variation in concrete with different binders\u003c/p\u003e","description":"","filename":"Picture10.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/0a8d15536f043d38a70f291b.jpg"},{"id":65949963,"identity":"1235fecb-8971-4f55-8fb7-a565873b923f","added_by":"auto","created_at":"2024-10-04 19:11:56","extension":"jpg","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":38831,"visible":true,"origin":"","legend":"\u003cp\u003eColour change of heated concrete surface along with the exposed aggregates, which wereheatedin anelectricmuffle furnace\u003c/p\u003e","description":"","filename":"Picture11.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/68836de85b2235296143a66d.jpg"},{"id":65949966,"identity":"9a10553e-0fd2-4bd5-8bea-5a0dbf930fcd","added_by":"auto","created_at":"2024-10-04 19:11:56","extension":"jpg","order_by":12,"title":"Figure 12","display":"","copyAsset":false,"role":"figure","size":211694,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of elevated temperature on mass loss variation in mortar with different binders\u003c/p\u003e","description":"","filename":"Picture12.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/d2389a433a2b898179bd493e.jpg"},{"id":65949965,"identity":"3ff3b52a-5096-4cfa-a4b2-0ceb36a769c6","added_by":"auto","created_at":"2024-10-04 19:11:56","extension":"jpg","order_by":13,"title":"Figure 13","display":"","copyAsset":false,"role":"figure","size":194980,"visible":true,"origin":"","legend":"\u003cp\u003eVariation of mass loss of different binders’ cubes specimen on elevated temperature\u003c/p\u003e","description":"","filename":"Picture13.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/41b83c5343d31db6e8c6c58e.jpg"},{"id":65949961,"identity":"a3fb0a1d-5797-47b5-841a-a317d2061077","added_by":"auto","created_at":"2024-10-04 19:11:56","extension":"jpg","order_by":14,"title":"Figure 14","display":"","copyAsset":false,"role":"figure","size":214871,"visible":true,"origin":"","legend":"\u003cp\u003eVariation of mass loss of different binders’ cylinder specimens on elevated temperature\u003c/p\u003e","description":"","filename":"Picture14.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/e197d573455149b65dba4cd9.jpg"},{"id":65949957,"identity":"e90bfb90-1848-4c73-bc5e-6b527dde49ba","added_by":"auto","created_at":"2024-10-04 19:11:55","extension":"jpg","order_by":15,"title":"Figure 15","display":"","copyAsset":false,"role":"figure","size":221244,"visible":true,"origin":"","legend":"\u003cp\u003eVariation of mass loss of different binders’ prism specimens on elevated temperature\u003c/p\u003e","description":"","filename":"Picture15.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/48dc8de046a50d0985027d6e.jpg"},{"id":66897848,"identity":"7fce1eef-7b49-468c-9bb2-72bbf657490e","added_by":"auto","created_at":"2024-10-17 15:46:51","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3729248,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5017589/v1/0fcffcb1-7cca-49d4-8aba-00140c781a79.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Mechanical Properties of Alkali Activated Slag Binder-based Concrete Exposed to Elevated Temperature","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eConcrete is widely employed in construction and civil engineering due to its flexibility, long-lasting nature, and ability to withstand fire(Amran et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). The demand for concrete as a construction material continues to rise steadily. Consequently, ordinary Portland cement (OPC) production increased from 1.5\u0026nbsp;billion tons in 1995 to a staggering 2.5\u0026nbsp;billion tons in 2015 (Hammad et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). According to current global projections, this figure could potentially increase by an additional 25% over the next decade, exacerbating the imminent scarcity of limestone within the next 25\u0026ndash;50 years (Naik, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). To address this issue, extensive research has been conducted for decades on replacing cement with alternative industrial by-products with high alumina and silica, known as aluminosilicates. Recently, this approach has gained significant popularity due to the growing interest in reducing the environmental impact of cement production. Aluminosilicates, which serve as common alternatives to OPC, contain substantial quantities of silicon oxide (SiO\u003csub\u003e2\u003c/sub\u003e) and aluminum oxide (Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e) (Yang \u0026amp; Song, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). Although Alkali-activated Concrete(AAC) exhibits certain drawbacks compared to OPC concrete, such as increased carbonation and shrinkage, it offers numerous advantages to the construction industry regarding durability and rapid strength development. Notably, the rapid strength development of AAC makes it a viable substitute for OPC in deep-water oil well cementing applications. The utilization of AAC concrete presents opportunities for reducing environmental impact while still meeting the construction industry's requirements for durability and strength (Jiapei et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eGGBFS isderived by rapidly cooling molten iron slag, a by-product of the iron and steel-making process, using water or steam. This cooling process produces a glassy and granular material, which is subsequently dried and finely ground into a powder. Blast furnace slag is generated when iron ore is combined with coke and subjected to high temperatures ranging from 1350 to 1550\u0026deg;C within a blast furnace.GGBFS serves as an environmentally friendly binding material that helps reduce CO\u003csub\u003e2\u003c/sub\u003e emissions. It is more durable than OPC and other pozzolanic materials. GGBFS can be used as a cementitious binder and admixture to produce traditional, high-performance concrete. Its inclusion enhances workability, durability, and long-term strength (Lee et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). Previous experimental studies have shown that GGBFS concrete exhibits a more uniform and optimized distribution of pore sizes, resulting in denser and more durable concrete structures (Chithambaram et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Singh et al., 2023). Moreover, GGBFS concrete demonstrates early strength development during high-temperature curing due to its temperature-dependent characteristics (Kishore, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Consequently, GGBFS is suitable for manufacturing precast concrete subjected to high-temperature curing. However, GGBFS possesses latent hydraulic properties and requires an alkaline activator to trigger its cementitious characteristics in producingAAC concrete (Amer et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Introducing an alkaline activator initiates a reaction between a strongly alkaline liquid and solid aluminum silicate material, forming N-A-S-H gel (Xu et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).Like the cement hydrate product C-S-H gel, this gel is known as an alkali-activated product (Sanni \u0026amp;Khadiranaikar, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2012\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis paper explores several studies concerning alternative materials for replacing Portland Slag Cement (PSC), specifically focusing on GGBFS. It is widely recognized that new binders are required to improve cement's environmental and durability performance. An alkali-activated (AA) binder was developed by combining GGBFS with alkali metal hydroxide and metal sulphate, serving as an activator. When mixed with slag, this activator produces a novel binder material that exhibits properties like conventional cement binders.Alumino-silicate materials, namely GGBS, are mixed with an alkali solution during the geopolymer preparation process. This mixture forms AlO\u003csub\u003e4\u003c/sub\u003e and SiO\u003csub\u003e4\u003c/sub\u003e tetrahedral units(Lecomte et al., \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2006\u003c/span\u003e), which are interconnected by shared oxygen atoms, resulting in polymeric structures known as poly(sialates), poly(sialate\u0026ndash;siloxo), or poly(sialate\u0026ndash;disiloxo), depending on the SiO\u003csub\u003e2\u003c/sub\u003e/Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e ratio. The impact of variables such as Si/Al, SiO\u003csub\u003e2\u003c/sub\u003e/Na\u003csub\u003e2\u003c/sub\u003eO, and Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e/Na\u003csub\u003e2\u003c/sub\u003eO on the system has been addressed in previous research (Komljenović et al, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; Ryu et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). The formation of polymeric precursors (-SiO\u003csub\u003e4\u003c/sub\u003e\u0026ndash;AlO\u003csub\u003e4\u003c/sub\u003e\u0026ndash;, -SiO\u003csub\u003e4\u003c/sub\u003e\u0026ndash;AlO\u003csub\u003e4\u003c/sub\u003e\u0026ndash;SiO\u003csub\u003e4\u003c/sub\u003e\u0026ndash;, or -SiO\u003csub\u003e4\u003c/sub\u003e\u0026ndash;AlO\u003csub\u003e4\u003c/sub\u003e\u0026ndash;SiO\u003csub\u003e4\u003c/sub\u003e\u0026ndash;SiO\u003csub\u003e4\u003c/sub\u003e\u0026ndash;) occurs through the sharing of all oxygen atoms between two tetrahedral units, accompanied by the release of water molecules (Davidovits, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). The connection between the tetrahedral frameworks is established through long-range covalent bonds. Geopolymer exhibits several advantages, including high compressive strength, fire resistance, low shrinkage, and excellent acid resistance.\u003c/p\u003e \u003cp\u003eTemperature is a significant factor that has a notable impact on the strength of concrete (Ozbayrak et al., 2023). Concrete can be exposed to elevated temperatures in both controlled and uncontrolled fire scenarios. Concrete subjected to high temperatures directly affects its compressive, tensile, and flexural strength (Zhang et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). One of the key reasons for strength loss in concrete at elevated temperatures is the development of cracks between the cement paste and aggregate due to thermal incompatibility between these components. However, normal-strength concrete generally exhibits better fire resistance than high-strength concrete (Phan \u0026amp; Phan, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e1996\u003c/span\u003e).Exposure to elevated temperatures causes significant changes in the concrete matrix's chemical composition and physical structure (Yasaswini\u0026amp; Rao, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). High temperature is a crucial factor in the physical deterioration processes that impact the stability and durability of concrete structures (Hertz, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2005\u003c/span\u003e). The behaviour of concrete under high-temperature conditions is greatly influenced by material properties, including the characteristics of the aggregate, cement paste, and the bond between the aggregate and cement paste (Arioz, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). Understanding how concrete structures and construction materials behave under elevated temperatures and fire conditions is of utmost importance for designers and researchers worldwide, as it directly affects the safety of human lives.\u003c/p\u003e \u003cp\u003eNevertheless, examining the high-temperature performance of alkali-activated GGBFS as a complete replacement for cement has been limited in previous studies. This study aims to fill this research gap in the existing literature. The present study demonstrates through experimental investigations that the AAC binder exhibits superior properties and is environmentally friendly, making it a promising substitute for OPC in construction and repair projects. However, these conclusions are solely based on testing conducted at ambient temperature.Understanding AAC's mechanical behavior under elevated temperatures is crucial. Therefore, a series of mechanical tests were carried out to examine the impact of elevated temperatures on Alkali Activated Slag Binder concrete. This study prepared concrete specimens using 100% Alkali-activated slag binder, comprising 94% GGBFS and 6% alkali activator and subjected to heating up to 800 ℃. Furthermore, a comparative benchmark test was performed using PSC and OPC43 concrete for reference.By investigating the mechanical properties of AAC concrete under elevated temperatures, this study aims to provide insights into its performance in challenging thermal conditions.\u003c/p\u003e"},{"header":"2. Experimental program","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Materials\u003c/h2\u003e \u003cdiv id=\"Sec4\" class=\"Section3\"\u003e \u003ch2\u003e2.1.1 Cement\u003c/h2\u003e \u003cp\u003eThe investigation utilized PSC from Lafarge Co. due to its favorable characteristics, including low heat of hydration, making it well-suited for mass construction. The physical properties of PSC were examined and are provided as follows: The fineness modulus, normal consistency, specific gravity, initial setting time, and final setting time of the binder were determined to be 3.0%, 33%, 3.06, 68 minutes, and 300 minutes, respectively (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). OPC of grade 43 is also used as a benchmark material for comparative purposes. The physical properties of OPC43 were measured as follows: The fineness modulus, normal consistency, specific gravity, initial setting time, and final setting time of the binder were determined to be 4%, 30%, 3.1, 48 minutes, and 262 minutes, respectively(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\u003ePhysical properties of conventional cement\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePhysicalRequirements\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePSC\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOPC43\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSpecificGravity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStandardConsistency\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e33%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSoundnessLe-Chatelier(mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSetting timeinitial(min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e48\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSetting timefinal(min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e262\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 \u003cdiv id=\"Sec5\" class=\"Section3\"\u003e \u003ch2\u003e2.1.2 GGBFS\u003c/h2\u003e \u003cp\u003eThe binder used in the study was GGBFS, which was obtained as industrial waste from Tata Steel Ltd. in Jamshedpur. This GGBFS complied with the IS: 12089 (1987). It is composed of various elements, including Lime (CaO), Silica (SiO\u003csub\u003e2\u003c/sub\u003e), Alumina (Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e), Magnesium oxide (MgO), Sulphur (S), Glass content, Ferric Oxide (Fe\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e), Loss on Ignition K\u003csub\u003e2\u003c/sub\u003eO. The chemical composition details of the binder materials utilized in the study are presented in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003eAdditionally, the dimensional modulus, specific gravity, and bulk density in the compacted state of the GGBFS were determined to be 2.83, 2.59, and 1670 kg/m\u003csup\u003e3\u003c/sup\u003e, respectively.\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\u003eChemical composition of different binders\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCompound\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGGBFS\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePSC\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOPC43\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCaO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e61.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e63.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e62.49\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSiO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e18.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20.27\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAl\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.32\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMgO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.46\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFe\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.16\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSO\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.53\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTiO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eK\u003csub\u003e2\u003c/sub\u003eO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.65\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMnO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNa\u003csub\u003e2\u003c/sub\u003eO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eP\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCeO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSrO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\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 \u003cdiv id=\"Sec6\" class=\"Section3\"\u003e \u003ch2\u003e2.1.3 AlkaliActivator\u003c/h2\u003e \u003cp\u003eIn this study, an activator was employed, which consisted of a mixture of metal hydroxides (MOH) and A\u003csub\u003e2\u003c/sub\u003eB. This activator is alkaline, contributing to a combined pH of approximately 13. A\u003csub\u003e2\u003c/sub\u003eB, a significant constituent of the activator, is primarily composed of SO\u003csub\u003e3\u003c/sub\u003e and Na\u003csub\u003e2\u003c/sub\u003eO. For a more detailed understanding of the composition and characteristics of A\u003csub\u003e2\u003c/sub\u003eB, please refer to Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, which provides a comprehensive description of this component. The specific properties of the activator, such as its alkalinity and major components, play a crucial role in its role as an activator in the study.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eChemical composition of alkali activator (A\u003csub\u003e2\u003c/sub\u003eB)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCompound\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eA2B%\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCaO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMgO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFe2O3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSO3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e80.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eK2O\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.19\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMnO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNa2O\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e16.36\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eP2O5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.02\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 \u003cdiv id=\"Sec7\" class=\"Section3\"\u003e \u003ch2\u003e2.1.4 Fine aggregate and coarse aggregate\u003c/h2\u003e \u003cp\u003eThe study utilized local fine-grained aggregates sourced from the Kharkai River, which meet the requirements specified in the IS 383:2016 standard for zone II. These aggregates exhibit the following characteristics: a fineness modulus of 2.83, specific gravity of 2.59, free moisture content of 0.2%, water absorption of 0.8%, bulking of sand of 3%, and a bulk density of 1560 kg per cubic meter in the compacted state.Additionally, coarse aggregates obtained from Jamshedpur, Jharkhand, were used in the experiment. The coarse aggregates were of two sizes: 20 mm and 12.5 mm. The 20 mm size coarse aggregate exhibited a fineness modulus of 6.81, specific gravity of 2.83, and water absorption of 0.35%. The 12.5 mm size coarse aggregate had a fineness modulus of 5.8, specific gravity of 2.54, and water absorption of 0.20%. These properties of the coarse aggregates are essential in determining their suitability for use in the study.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Casting and curing\u003c/h2\u003e \u003cp\u003eTo conduct the experiment, the alkali-activated binder was prepared using 94% GGBFS 3% metal hydroxides, and 3% metal sulphates as alkali activators. Fine aggregate was sourced from Tata Steel Pvt. Ltd., while the coarse aggregate was obtained from the Kharkai river bed and locally available rock stone aggregate. All materials used in the experiment were found to comply with the IS 383\u0026ndash;1970 standard.The activator solution was prepared by mixing the activators with water and stirring for 10 minutes to achieve a homogeneous consistency. The alkali binder, sand, and aggregate were then mixed according to the IS: 10262 (2009) specifications. The proportions of the concrete mix are listed in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMix design proportions of different constituents\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eS. No.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eIngredients\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMass of materials (kg)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMix proportion\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBinder content\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e352.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003e1:1.9:3.38\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFine aggregate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e672.39\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCoarse aggregate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1194.14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWater\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e173\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\u003eThe mix was used to cast 26 specimens, including size 150 X 150 X 150 mm cubes, cylindrical specimens with a diameter of 150 mm and length of 300 mm, and prism specimens measuring 500 X 100 X 100 mm. After being kept in the moulds for 24 hours, the specimens were subjected to water-curing conditions.\u003c/p\u003e \u003cp\u003eThe concrete mixtures were designed based on the absolute volume method for M25 grade concrete, following the guidelines of IS: 10262 (2009). The materials were proportioned by weight, resulting in a final mix proportion of 1:1.9:3.38, with a fixed water-cement ratio of 0.49. The desired workability was achieved by targeting a slump value within the 90\u0026thinsp;\u0026plusmn;\u0026thinsp;10 mm range.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Testing\u003c/h2\u003e \u003cp\u003eThe workability of concrete refers to its ability to be easily mixed and achieve a uniform consistency. It is primarily influenced by the water-cement ratio, with higher ratios resulting in increased workability. The workability was evaluated using the slump cone test (100 X 200 X 300 mm) according to IS: 1199 (1959). This test was performed batch-to-batch to ensure consistent concrete quality during casting.\u003c/p\u003e \u003cp\u003eThe compressive strength of concrete represents the maximum uniaxial stress it can withstand before failure. The compressive strength of the cube specimens was tested using a universal testing machine with a capacity of 3,000 kN, and the loading ratewas 140 kg/cm\u003csup\u003e2\u003c/sup\u003e/min. It is determined by dividing the failure load by the cross-sectional area resisting the load, which is reported in N/mm\u003csup\u003e2\u003c/sup\u003e. Compressive strength tests were conducted on 150 mm cube specimens following IS:516\u0026ndash;1959, using a digital compression testing machine after curing for 3, 7, and 28 days.Tensile strength is a crucial property of concrete, although it is inherently weak in tension and prone to cracking under tensile forces. The split tensile strength (T) was calculated using Eq.\u0026nbsp;\u003cspan refid=\"Equ1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e\u003cdiv class=\"EquationNumber\"\u003e\u003cimg src=\"data:image/png;base64,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\"\u003e 1\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere;\u003c/p\u003e \u003cp\u003eP\u0026thinsp;=\u0026thinsp;Applied load\u003c/p\u003e \u003cp\u003eD\u0026thinsp;=\u0026thinsp;Diameter of the cylinder\u003c/p\u003e \u003cp\u003eL\u0026thinsp;=\u0026thinsp;Length of the cylinder\u003c/p\u003e \u003cp\u003eThe split tensile strength test was performed on (300 X 150) mm cylinder specimens according to IS:516\u0026ndash;1959. The split tensile of the cylinders specimens were tested using a universal testing machine with a capacity of 3,000 kN, and the loading rates for the split tensile strength test were 1.2\u0026ndash;2.4 N/mm\u003csup\u003e2\u003c/sup\u003e/min. Flexural strength measures a concrete\u0026rsquo;s ability to withstand bending caused by factors such as temperature changes. It was determined using (100 X 100 X 500) mm beam specimens under two-point loading, following IS:516\u0026ndash;1959. The flexural strength was calculated using Eq.\u0026nbsp;\u003cspan refid=\"Equ2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, considering a shear span (a) less than 110 mm.\u003cdiv id=\"Equ2\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ2\" name=\"EquationSource\"\u003e\n$$\\:{F}_{b}=\\frac{PL}{b{d}^{2}}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e2\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eTo investigate the effect of elevated temperatures, the specimens were heated in an electric muffle furnace at temperatures ranging from 100\u003csup\u003eo\u003c/sup\u003eC to 800℃. The heating rate was set at 10\u0026deg;C/minute until the desired temperature was reached, and then it was maintained for 4 hours before allowing the specimens to cool naturally to room temperature.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results and discussions","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Compressive strength of mortar on ambient temperature\u003c/h2\u003e \u003cp\u003eThe results displayed in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e depict the compressive strength of mortar samples made with GGBFS, PSC, and OPC43. The compressive strength values at the curing period of 28 days for PSC, GGBFS, and OPC43 mortar were recorded as 33.92 N/mm\u0026sup2;, 35.39 N/mm\u0026sup2;, and 43.79. N/mm\u0026sup2;, respectively.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe study examined the compressive strength of GGBFS mortar(Chithambaram et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) and compared it with two other types of mortar: PSC and OPC 43. Upon analyzing the results, it was found that GGBFS mortar demonstrated distinct compressive strength characteristics.The compressive strength of GGBFS mortar was approximately 4.33% higher than PSC. This indicates that GGBFS mortar outperforms PSC in terms of compressive strength, suggesting it could be a favorable option in certain applications requiring higher strength.On the other hand, when compared to OPC43, the compressive strength of GGBFS mortar was 19.18% lower. This substantial difference indicates that OPC43 still maintains a significant advantage over GGBFS mortar regarding compressive strength. The findings suggest that regarding compressive strength, GGBFS mortar falls between PSC and OPC43. It exhibits a slight advantage over PSC but falls significantly short of OPC43.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Compressive strength of concrete on ambient and elevated temperature\u003c/h2\u003e \u003cp\u003eA comparison was conducted to evaluate the compressive strength of alkali-activated slag concrete with PSC concrete and OPC43 concrete. Figures\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e presented the compressive strength results under ambient and elevated temperatures, respectively. After 28 days of curing, the compressive strength values were recorded as 29.11 N/mm\u003csup\u003e2\u003c/sup\u003e, 32.54 N/mm\u003csup\u003e2\u003c/sup\u003e, and 36.54 N/mm\u003csup\u003e2\u003c/sup\u003e for PSC, GGBFS, and OPC43 concrete. Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e revealed that GGBFS concrete achieved a significantly higher compressive strength than PSC concrete, with approximately 11.78% improvement at the age of 28 days. Conversely, compared to OPC43 concrete, GGBFS concrete exhibited a lower compressive strength, with a reduction of approximately 10.95% at 28 days.\u003c/p\u003e \u003cp\u003eThe compressive strength of alkali-activated slag concrete consistently surpassed that of PSC concrete. However, when compared to OPC43 concrete, alkali-activated slag concrete demonstrated lower compressive strength values.The results indicate that GGBFS concrete outperformed PSC concrete in terms of compressive strength, exhibiting higher values. However, when compared to OPC43 concrete, GGBFS concrete displayed lower compressive strength.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe study investigated the compressive strength of different binder concretes under ambient conditions and then subjected them to testing at elevated temperatures (Figs.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). The results in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e indicate the changes in compressive strength as the temperature was raised from ambient to 100\u003csup\u003eo\u003c/sup\u003eC(Shen and Xu, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Pratap and Kumar, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2024\u003c/span\u003e).As the temperature increased from ambient to 100\u003csup\u003eo\u003c/sup\u003eC (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), the compressive strength of PSC, GGBFS, and OPC43 concrete showed varying degrees of improvement(Tayeh et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Specifically, PSC concrete experienced an 11.06% increase in compressive strength, while GGBFS and OPC43 concrete demonstrated smaller improvements of 1.09% and 5.23%, respectively.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAs the temperatures continued to rise beyond 100\u003csup\u003eo\u003c/sup\u003eC, the compressive strength of the concretes exhibited a reduction. For PSC concrete, the decrease in compressive strength ranged from 10.54% to as much as 78.16%, indicating a significant loss in strength. GGBFS concrete experienced a compressive strength reduction of 3.84\u0026ndash;72.43%, while OPC43 concrete showed the most substantial decline, ranging from 3.17% to a remarkable 96.69% (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Split tensile strength of concrete on ambient and elevated temperature\u003c/h2\u003e \u003cp\u003eThis study compared the split tensile strength of alkali-activated slag concrete with that of PSC concrete and OPC43 concrete. Figures\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e, \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e, and \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e presented the results for split tensile strength under ambient and elevated temperatures, respectively. After a curing period of 28 days, the split tensile strength values were measured as 4.7 N/mm\u003csup\u003e2\u003c/sup\u003e, 4.9 N/mm\u003csup\u003e2\u003c/sup\u003e, and 5.4 N/mm\u003csup\u003e2\u003c/sup\u003e for PSC, GGBFS, and OPC43 concrete, respectively.From Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e, it was evident that GGBFS concrete exhibited significantly higher split tensile strength than PSC concrete, with an approximate 4.26% improvement at the age of 28 days. In contrast, compared to OPC43 concrete, GGBFS concrete displayed lower split tensile strength, showing a reduction of approximately 15.52% at the same age.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eConsistently, alkali-activated slag concrete demonstrated higher split tensile strength values than PSC concrete across the various test conditions. However, when compared to OPC43 concrete, alkali-activated slag concrete exhibited lower split tensile strength values.The study aimed to analyze the split tensile strength of different binder concretes under both ambient and elevated temperature conditions (Figs.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e and \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). As the temperature increased from ambient, the split tensile strength of PSC, GGBFS, and OPC43 concrete began to decrease (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e)(Husem, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). As the elevated temperatures continued to rise beyond the ambient level, the split tensile strength of all concretes exhibited a significant reduction. For PSC concrete, the decrease in split tensile strength ranged from 10.64% to as much as 76.59%, indicating a substantial loss in its ability to withstand tensile forces. Similarly, GGBFS concrete experienced a split tensile strength reduction of 8.20\u0026ndash;73.47%, showing its vulnerability to elevated temperatures(Tayeh et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).The most substantial decline was observed in OPC43 concrete, with its split tensile strength dropping from 13.79% to an astounding 75.86% (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). These findings indicate that OPC43 concrete is highly sensitive to increasing temperatures and tends to suffer a severe reduction in its split tensile strength as it rises.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe study's results highlight the negative impact of elevated temperatures on the split tensile strength of different binder concretes. Understanding this behaviour is crucial for selecting appropriate concrete types in applications where the material may be exposed to elevated temperatures, as it helps ensure the structural integrity and safety of concrete structures under varying environmental conditions.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003e3.4 Flexural strength of concrete on ambient and elevated temperature\u003c/h2\u003e \u003cp\u003eOne of the focuses of the present study is to compare the flexural strength of alkali-activated slag concrete with that of PSC concrete and OPC 43 concrete. Figures\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e8\u003c/span\u003e, \u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e9\u003c/span\u003e, and \u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e10\u003c/span\u003e presented the results for flexural strength under ambient and elevated temperature conditions, respectively. After a curing period of 28 days, the flexural strength values were recorded as 4.7 MPa, 4.9 MPa, and 5.4 MPa for PSC, GGBFS, and OPC 43 concrete, respectively. Figure\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e8\u003c/span\u003e indicated that GGBFS concrete exhibited significantly higher flexural strength than PSC concrete, with an approximate 8.51% improvement at 28 days. This suggests that GGBFS concrete demonstrates enhanced resistance to bending forces compared to PSC concrete.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eHowever, compared to OPC 43 concrete, GGBFS concrete displayed lower flexural strength, with a reduction of approximately 12.07% at the same age. This implies that OPC43 concrete outperforms GGBFS concrete in flexural strength, demonstrating a higher ability to withstand bending stresses. The findings indicate that GGBFS concrete performs better than PSC concrete in flexural strength, exhibiting higher values. However, compared to OPC43 concrete, GGBFS concrete showed lower flexural strength.\u003c/p\u003e \u003cp\u003eThis study section examines the flexural strength of different binder concretes under ambient and elevated temperature conditions, as illustrated in Figs.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e9\u003c/span\u003e and \u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e10\u003c/span\u003e. As the temperature increased from the ambient level, the flexural strength of PSC, GGBFS, and OPC43 concrete began to decline. As the elevated temperatures continued to rise beyond the ambient level, the flexural strength of all concrete types exhibited a significant reduction (Fig.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003ePSC concrete experienced a decrease in flexural strength ranging from 12.76% to an alarming 85.10%, indicating a substantial loss in its ability to withstand bending forces. Similarly, GGBFS concrete demonstrated a flexural strength reduction(Yasaswini\u0026amp; Rao, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) of 3.92\u0026ndash;80.27%, indicating its susceptibility to elevated temperatures. The most substantial decline was observed in OPC43 concrete, with its flexural strength decreasing from 12.07% to a remarkable 84.48% (Fig.\u0026nbsp;\u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e10\u003c/span\u003e). These findings emphasize that OPC43 (Husem, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2006\u003c/span\u003e)concrete is highly sensitive to increasing temperatures and undergoes a significant reduction in flexural strength as the temperature rises.\u003c/p\u003e \u003cp\u003eThe study highlights the impact of elevated temperatures on the flexural strength of different binder concretes. It indicates that as temperatures increase beyond ambient, all concrete types experience a decrease in flexural strength.\u003c/p\u003e \u003cp\u003eIn Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e11\u003c/span\u003e, the researchers investigated the colour change of concrete when exposed to elevated temperatures. They examined the external surface of the concrete element and focused on areas where visible aggregates were present. The observed colour changes are depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e8\u003c/span\u003e. The researchers found that the colour of the concrete varied depending on the temperature it was subjected to. Between 100\u0026ndash;300\u0026deg;C, the concrete transformed from grey to whitish grey. At temperatures ranging from 400\u0026ndash;600\u0026deg;C, it turned reddish. Finally, when exposed to 800\u0026deg;C, the concrete became buff.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThese colour changes can be attributed to two main factors: the gradual removal of water and dehydration of the cement paste and the transformations occurring within the aggregate.As the concrete is exposed to elevated temperatures, the heat causes the moisture present in the cement paste to evaporate gradually. This process of water removal and dehydration leads tochanges in the colour of the concrete.Additionally, the aggregates within the concrete also undergo transformations under high temperatures. The siliceous aggregate's specific chemical and mineral composition plays a role in the observed colour changes. The interaction between the aggregate and the heat alters the aggregate's physical and chemical properties, which, in turn, affects the colour of the concrete.\u003c/p\u003e \u003c/div\u003e"},{"header":"4. Mass loss of different specimens","content":"\u003cp\u003eConcrete samples were subjected to oven drying, causing them to lose mass due to water evaporation or other factors. The percentage mass loss of mortar, concrete cubes, cylinders, and prisms can be observed in Figs.\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e12\u003c/span\u003e, \u003cspan refid=\"Fig14\" class=\"InternalRef\"\u003e13\u003c/span\u003e, \u003cspan refid=\"Fig15\" class=\"InternalRef\"\u003e14\u003c/span\u003e, and \u003cspan refid=\"Fig16\" class=\"InternalRef\"\u003e15\u003c/span\u003e, respectively. This experiment likely aimed to study how different concrete shapes and compositions react to drying, providing valuable insights into their durability and water-retention capabilities.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e12\u003c/span\u003e illustrates that the mass loss of mortar specimens rises with higher temperatures. The percentage mass loss varies for different cement types: PSC shows a range of 2.4\u0026ndash;9.9%, GGBFS exhibits 2.1\u0026ndash;9.4% loss, and OPC 43 has a range of 1.1\u0026ndash;8.2% loss. These findings suggest that as the temperature increases, all three binder types experience increased mass loss, with PSC demonstrating the highest susceptibility to loss, followed by GGBFS and OPC43. Understanding these variations is vital for designing and selecting appropriate cement types for different temperature conditions in construction projects.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig14\" class=\"InternalRef\"\u003e13\u003c/span\u003e depicts the relationship between temperature and mass loss in concrete cube specimens. As the temperature rises, the mass loss of the specimens also increases. The percentage mass loss varies among different cement types: PSC shows a range of 0.87\u0026ndash;8.8%, GGBFS exhibits a range of 0.69\u0026ndash;7.9% loss, and OPC 43 has a range of 0.55\u0026ndash;7.4% loss. These findings indicate that PSC is the most susceptible to mass loss at higher temperatures, followed by GGBFS and OPC 43.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig15\" class=\"InternalRef\"\u003e14\u003c/span\u003e illustrates the relationship between temperature and mass loss in concrete cylinder specimens. With an increase in temperature, the specimens experience higher mass loss. The percentage mass loss varies across different cement types: PSC exhibits a range of 0.85\u0026ndash;6.3% loss, GGBFS shows a range of 0.78\u0026ndash;5.9% loss, and OPC43 demonstrates a range of 0.56\u0026ndash;5.5% loss. These results indicate that PSC is the most vulnerable to mass loss at elevated temperatures, followed by GGBFS and OPC43.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig16\" class=\"InternalRef\"\u003e15\u003c/span\u003e displays the correlation between temperature and mass loss in concrete prism specimens. As the temperature increases, the specimens undergo greater mass loss. The percentage mass loss differs for various cement types: PSC shows a range of 0.45\u0026ndash;5.4% loss, GGBFS exhibits a range of 0.35\u0026ndash;5.1% loss, and OPC43 demonstrates a range of 0.22\u0026ndash;4.2% loss.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"5. Conclusions","content":"\u003cp\u003eIn conclusion, compressive, split, and flexure strengths of geopolymer concreteunder ambient and elevated temperatures have been thoroughly investigated and analyzed. The findings from various studies highlight the response and behaviour of geopolymer concrete when subjected to high temperatures, providing valuable insights for the construction industry.Extensive research and analysis have been conducted on polymer concrete under ambient and elevated temperature conditions. The primary objective of these studies is to gain valuable insights into the behaviour, properties, and overall performance of polymer concrete when subjected to varying temperature levels. The key findings and conclusions derived from these investigations are outlined below:\u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eIn conclusion, the analysis of the compressive strength values of GGBFS mortar at different curing periods of 28 days revealed that its strength ishigher compared to both PSC and lower than the OPC43. Specifically, the compressive strength of GGBFS mortar was approximately 4.33% higher than PSC and 19.18% lower than OPC43. These findings suggest that GGBFS mortar can be a viable alternative with improved strength characteristics compared to PSC, albeit still falling short of the strength exhibited by OPC43.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eAfter 28 days of curing, compressive strength values were 29.11 N/mm\u003csup\u003e2\u003c/sup\u003e for PSC, 32.54 N/mm\u003csup\u003e2\u003c/sup\u003e for GGBFS, and 36.54 N/mm\u003csup\u003e2\u003c/sup\u003e for OPC43 concrete. GGBFS achieved 11.78% higher strength than PSC and 10.95% lower compressive strength than OPC43. At 100\u0026deg;C, the compressive strength of PSC, GGBFS, and OPC43 simproved. However, at temperatures beyond 100\u0026deg;C, all concretes weakened significantly. PSC reduced by 10.54\u0026ndash;78.16%, GGBFS by 3.84\u0026ndash;72.43%, and OPC43 by 3.17% to a substantial 96.69%. Higher temperatures negatively impacted compressive strength across all concrete types.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eIn conclusion, GGBFS concrete showed significantly higher split tensile strength than PSC concrete after 28 days, with a 4.26% improvement. However, it exhibited lower split tensile strength than OPC43 concrete, with a reduction of approximately 15.52%. As temperatures increased, all concrete experienced notable decreases in split tensile strength, with PSC, GGBFS, and OPC43 showing reductions ranging from 10.64\u0026ndash;76.59%, 8.20\u0026ndash;73.47%, and 13.79\u0026ndash;75.86%, respectively, indicating their susceptibility to elevated temperatures.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eafter 28 days of curing, the flexural strength values were 4.7 N/mm\u003csup\u003e2\u003c/sup\u003e for PSC, 4.9 N/mm\u003csup\u003e2\u003c/sup\u003e for GGBFS, and 5.4 N/mm\u003csup\u003e2\u003c/sup\u003e for OPC43 concrete. GGBFS concrete exhibited significantly higher flexural strength than PSC concrete, with an approximate 8.51% improvement. However, GGBFS concrete showed lower flexural strength than OPC43 concrete, with a reduction of approximately 12.07%. As temperatures increased, all concrete types experienced a decline in flexural strength. PSC concrete showed a significant decrease ranging from 12.76\u0026ndash;85.10%, GGBFS concrete exhibited a reduction of 3.92\u0026ndash;80.27%, and OPC43 concrete displayed the most substantial decline from 12.07\u0026ndash;84.48%.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eThe evaluation of test specimens at elevated temperatures demonstrated that only the residual compressive strength increased as the temperature rose from ambient to 100\u0026deg;C, followed by a subsequent decrease. However, the residual split tensile and flexural strength immediately declined upon increasing the temperature from ambient conditions.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eThe evaluation of mass loss in different test samples revealed distinct patterns. The PSC sample demonstrated higher mass loss, indicating a greater weight reduction than the other samples. On the other hand, the OPC43 sample exhibited lesser mass loss, suggesting a relatively lower reduction in weight. The GGBFS sample displayed intermediate mass loss, falling between the levels observed in the PSC and OPC43 samples. These results suggest variations in the susceptibility of the different cement types to undergo mass loss during the evaluation process.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003c/p\u003e \u003cp\u003eThe study's conclusion suggests that GGBFS can be considered a favorable replacement for PSC in various construction applications. The research indicates that GGBFS exhibits superior performance compared to PSC, making it a potentially better alternative. However, it is worth noting that GGBFS shows lower results than OPC43 in certain aspects. This calls for further investigation and assessment to understand better the specific scenarios where GGBFS can be optimally utilized and address potential limitations. Additional research will help validate its practical applications in construction projects.\u003c/p\u003e "},{"header":"Declarations","content":"\u003cp\u003e \u003cb\u003eCredit authorship contribution statement\u003c/b\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eRajesh Kumar Paswan\u003c/b\u003e: Methodology, Investigation, Writing - original draft. \u003cb\u003ePramod Kumar\u003c/b\u003e:Writing \u0026ndash; review \u0026amp; editing. \u003cb\u003eVirendra Kumar\u003c/b\u003e:Investigation, Review \u0026amp; editing, Supervision.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConflict of interest:\u003c/strong\u003e \u003cp\u003eThe authors declare that there is no conflict of interest regarding thepublication of this paper.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eNone. No funding to declare.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eA. Rajesh Kumar Paswan: Investigation, Methodology, Visualization, Resources, Writing - review \u0026amp; editing.B. Virendra Kumar: Formal analysis, Conceptualization, Validation, Visualization, Writing- Original draft, Writing - review \u0026amp; editing.T. Pramod Kumar: Methodology, Visualization\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eThe authors would like to thank to the Research and Development division, Tata Steel Ltd., Jamshedpur for the supply of Ground Granulated Blast Furnace Slag (GGBFS). The authors would like to thank the Department of Civil Engineering, R.V.S College of Engineering and Technologuy, Jamshedpur, for providing there research facilities. The authors would also like to thank N. Ramkumar, Ph.D., Director, Navoday Sciences Pvt. Ltd., Chennai for supplying the activator along with the technical input.\u003c/p\u003e\u003ch2\u003eData availability:\u003c/h2\u003e \u003cp\u003eData will be made available at the request of the corresponding author.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAmran M, Huang SS, Debbarma S, Rashid RS (2022) ,Fire resistance of geopolymer concrete: A critical review. Constr Build Mater 324:126722\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAmer I, Kohail M, El-Feky MS, Rashad A, Khalaf MA (2021) ),A review on alkali-activated slag concrete. Ain Shams Eng J 12(2):1475\u0026ndash;1499\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eArioz O (2007) ,Effects of elevated temperatures on properties of concrete. Fire Saf J 42(8):516\u0026ndash;522\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChithambaram SJ, Kumar S, Prasad MM (2019) ,Thermo-mechanical characteristics of geopolymer mortar. 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Constr Build Mater 109:17\u0026ndash;24\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"GGBFS, Elevated Temperatures, CompressiveStrength, Split TensileStrength, Flexural Strength","lastPublishedDoi":"10.21203/rs.3.rs-5017589/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5017589/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eFire is a catastrophic event that significantly threatens structures. As a fire progresses, the strength of concrete deteriorates over time due to the high temperatures. Understanding how the concrete's strength diminishes under high temperatures. The present study is motivated by focusing on how alkali-activated concrete responds to elevated temperatures.There is a growing trend of using ground granulated blast furnace slag (GGBFS) as a constituent material in both normal strength and high-performance concrete. When combined with sodium hydroxide and sodium sulphate powder as activators, this material forms Alkali-activated Concrete(AAC). This research paper investigates the impact of high temperatures on the compressive strength, split tensile strength, and flexural strength of AAS concrete. Test specimens were subjected to temperatures of 100\u0026deg;C, 200\u0026deg;C, 300\u0026deg;C, 400\u0026deg;C, 500\u0026deg;C, 600\u0026deg;C, 700\u0026deg;C and 800\u0026deg;C.The research indicates that AACperforms better than regular binder concrete, making it a potentially better alternative.\u003c/p\u003e","manuscriptTitle":"Mechanical Properties of Alkali Activated Slag Binder-based Concrete Exposed to Elevated Temperature","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-10-04 19:11:50","doi":"10.21203/rs.3.rs-5017589/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d83a5b36-c66d-4f81-8fb3-68df3a55e4d4","owner":[],"postedDate":"October 4th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-10-17T15:38:41+00:00","versionOfRecord":[],"versionCreatedAt":"2024-10-04 19:11:50","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5017589","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5017589","identity":"rs-5017589","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}