Influence of joint form on shear characteristics of asphalt concrete core under steep bank slope condition

Influence of joint form on shear characteristics of asphalt concrete core under steep bank slope condition | 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 Influence of joint form on shear characteristics of asphalt concrete core under steep bank slope condition Yong Li, Yanlong Li, Yunhe Liu, Xinjian Sun, Lifeng Wen, Weimei Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3988129/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 The connection performance between the core and the concrete plinth under steep bank slope conditions is related to the overall seepage safety of the dam. In this study, combined with the actual engineering, the steep slope control groups with slopes of 71°, 76° and 81° were designed. The research scheme not only considers the limit situation of the existing specifications, but also makes further exploration on the situation of high and steep valleys beyond the specifications. Considering the asymmetric valley and the symmetric valley, two contact forms of arc joint and flat joint are set up. Based on the numerical calculation, the influence of the joint embedding depth and the amplification angle on the shear action of the asphalt concrete core (ACC) is quantitatively studied. The results indicate that the symmetry of the valley will cause stress to deflect, affecting the characteristics of shear stress of the core. Under the condition of high-steep bank slope, large shear deformation occurs at the joint of ACC, and significant arching occurs near the bank slope. The overall stress level of the arc joint is higher than that of the flat joint, and it is highly sensitive to the change of the bank slope. Increasing the embedded depth of the joint, the local shear effect of the core wall becomes larger. As the joint magnification angle decreases, the stress level of the core and the maximum shear stress decrease. Expanding the contact surface of the joint can reduce the shear effect of the core. This study breaks through the conventional dam construction conditions and explores the mechanical properties of anti-seepage bodies in high and steep valleys. The research results of this paper can provide reference for the design of ACC joints under extreme steep bank slope conditions. asphalt concrete core steep bank slope joint form stress shear deformation 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 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 1 Introduction In recent years, more and more dams choose asphalt concrete core rockfill dams (ACCRDs) because of their strong adaptability to deformation and good plasticity [ 1 ] . Under the condition of high-steep bank slope, the joint part of ACC and plinth may have large shear deformation, which seriously endangers the impermeability and safety of dam body and core [ 2 ] . Therefore, it is of great significance to study the shear stress law of the joint of ACC under the condition of high - steep bank slope [ 3 ] , which is of great guiding significance to the construction of 100-meter-class ACCRD. At present, the research on the shear characteristics of ACC by scholars at home and abroad is mainly summarized into two aspects, namely model test and numerical simulation. On the one hand, in the model experiments, the mechanical properties of the core are mainly studied by the shear effect of the two interfaces [ 4 ] . Tajdini et al. (2014) [ 5 ] considered the interface between mortar and asphalt concrete under dry and saturated conditions. Through small-scale direct shear tests, the effects of asphalt permeability grade, moisture and density on shear strength under different normal stress levels and constant shear rates were carried out. Wang et al. (2018) [ 6 ] carried out shear tests on the interface between ACC and transition layer, and studied and evaluated the behavior of shear displacement between the two. As shown in Fig. 1, another type is the connection between the ACC and the concrete structure, which belongs to the soft asphalt-rigid concrete interface. Wang et al. (2010) [ 7 ] conducted a special model test to study the connection behavior between the narrow asphalt core and the plinth. The results of the water storage test showed that the seepage through the ACC and the core - plinth interface was very small. Kong et al. (2013) [ 8 ] obtained that the inclination of the core of the arc joint type is slightly larger than that of the horizontal joint type through the shaking table model analogy test. Wang et al. (2017) [ 9 ] proposed to embed a row or two rows of water stops in the plinth to strengthen the connection of the asphalt core plinth when studying the optimal ratio of SAM at the connection between the core and the plinth. The existing model test is limited to small size, failing to consider the overall structure of the core, and failing to fully reflect the evolution law of the overall stress and deformation of the core. On the other hand, in the numerical analysis, Li et al. (2023) [ 10 ] combined with the reliability theory to analyze the crack resistance reliability of ACC under the action of water storage. The calculation results show that there is tensile stress concentration near the slope of both sides of the core, but the generation of tensile stress has not been further studied. It is worth noting that there is often a close relationship between the generation of tensile stress and shear action. Based on numerical calculation, Li et al. (2023) [ 11 ] quantitatively studied the arch effect mechanism of ACC under complex topographic and geological conditions. The study shows that there is a significant shear effect between the core and the bank slope due to the constraints of the valley terrain. In order to quantify the magnitude of shear action, Gao et al. (2019) [ 12 ] proposed the shear safety control standard of ACC based on the stress characteristics of ACC in different periods. In general, the current research on ACCRDs at home and abroad is mainly aimed at the general valley terrain, and there are few studies on the impermeability and safety of the joint between the asphalt core and the base under the condition of high-steep bank slopes. Therefore, it is necessary to consider the condition of high - steep bank slope and carry out the research on the shear action law of ACC and base joint. In this study, based on the finite element method, this study first compares and analyzes the adaptability of arc joints and flat joints to different types (asymmetric valleys, symmetrical valleys) of steep slope valleys. On this basis, the stress deformation law of the ACC joint under the condition of steep bank slope is deeply analyzed in terms of the embedded depth and the magnification angle. Revealing the seepage resistance and safety of the dam body and core after shear deformation occurs at the joint areas of steep bank slope. To clarify the applicability of high ACCRDs with steep bank slope, with a view to providing a deeper understanding of the shear deformation of the core of ACCRDs, and to provide some references for practical projects. 2 Feasibility study on shear behavior of core-plinth 2.1 Core-plinth stress characteristics Figure 2 is the stress diagram of asphalt concrete core - plinth. The AACC is buried inside the rockfill body, and the stress is complex. Its mechanical properties need to comprehensively consider the combined effects of its own load (self-weight) and surrounding structures (friction, earth pressure, water load, etc.) [ 12 ] . When analyzing the mechanical properties of ACC, it is necessary to comprehensively consider the combined effect of transition layer and rigid contact. The connection between ACC and concrete concrete structure belongs to soft asphalt-rigidity. Because soft - hard contact is in two areas of different materials and deformation ability, there will be obvious shear effect, and shear stress will be generated at the interface, among which the stress at the junction is more concentrated. During the construction and operation of the dam, the ACC may have a large shear displacement at the joint of the steep bank slope, and it is easy to produce tensile stress and lead to tensile failure at the shoulder of the high and steep bank slope. This requires that the ACC has a large deformation capacity at the joint of the steep bank slope to prevent shear and tensile failure. When the valley terrain is narrow valley, both sides of the valley bank slope is relatively stable and strong structure. The core extrudes and deforms toward the middle of the valley, and the bank slope provides a stable arch footing for the core stress arching [ 13 ] . Reasonable quantification and mitigation of shear stress is the focus of research. 2.2 Measuring the load capacity At present, the most common method to determine whether the shear failure of ACC occurs is to calculate the ratio of shear stress to failure shear stress, that is, to solve the stress level. The detailed expression is shown in Eq. ( 1 ) [ 14 ] . The stress level is an important index to judge the limit equilibrium zone in the dam body, and the stress level reflects the degree of strength of the dam material. If the stress level of each part of the dam is less than 1.0, the dam will not be sheared. $$S=\frac{{{\sigma _1} - {\sigma _3}}}{{{{({\sigma _1} - {\sigma _3})}_f}}}=\frac{{({\sigma _1} - {\sigma _3})(1 - \sin \varphi )}}{{2c\cos \varphi +2{\sigma _3}\sin \varphi }}$$ 1 Where S is stress level; σ 1 is major principal stress; ( σ 1− σ 3 ) f is limit principal stress difference; c is cohesion; φ is angle of internal friction. During the impoundment period, the lateral deformation of the core increases under the action of horizontal water pressure, the axial elongation of the core increases, and the tensile strain increases, resulting in an increase in tensile stress. The ACC is very thin compared with the rockfill material, and its tensile strength is generally between 0.19 ~ 0.78 MPa. Through the tensile test, the tensile strength of ACC in Quxue Hydropower Station reaches 0.60 MPa. When the calculated maximum tensile stress \({\sigma _{\hbox{max} }}\) is greater than the tensile strength \({\sigma _t}\) of the core, it is proved that the core is fractured and cracks are generated. The corresponding relation is shown in expression (2). $${\sigma _{\hbox{max} }} \leqslant {\sigma _t}$$ 2 In the case of narrow valley, there is a strong shear between the core and the rock on both sides, resulting in the transfer of stresses, and the core will produce a significant arching action. The magnitude of the arching can be described by the arching coefficient, which is defined as the ratio of the vertical stress in the cell σ Z to the self-weight of the soil bar on the cell γh , as shown in Eq. ( 3 ) [ 15 ] . Some researchers believe that horizontal cracks may occur in the core when the vertical stress of the core is 20% -50% of the vertical stress of the adjacent dam shell at the same elevation [ 16 ] . $$R=\frac{{{\sigma _Z}}}{{\gamma h}}$$ 3 Where σ z is vertical stress; γ is unit weight; h is the thickness of the soil above the element calculated. The smaller the arching coefficient, the stronger the arching. When the arching coefficient is less than 1, it indicates that the stress is being transferred from the core to the transition layer as well as the dam shell. Therefore, based on the above analysis, in order to more intuitively compare the safety of the core, we mainly introduce the above three criteria for the mechanical properties of the asphalt concrete core. 3 Engineering case and calculation scheme 3.1 Engineering case Statistics show that nearly 200 ACEDs have been constructed. Some typical examples of ACEDs are the 125-meter-high Storglomvatn dam, the 125-meter-high Yele dam and the 85-meter-high Feistritzbach dam. Some of them are more than 150 meters high, 153 meters high Zarema dam. The dam built in 2017 in China is 174 meters high, which is the highest ACCRD in the world [ 6 ] . Table 1 lists the data of 20 typical ACCRDs in the world, where H C is the height of the core, H D is the maximum dam height corresponding to the location of the core, T is the thickness of the core, L C is the length of the dam axis, and W is the bottom width of the enlarged foot of the core. The height of most dams is between 40 and 130 m, and the total dam height ranges from 45 to 173 m. The length of the axis of the dam is relatively discrete, which is closely related to the form of the valley. The overall aspect ratio is about 1 ~ 8.5. In comparison, the thickness of the core is relatively stable, which basically belongs to the range of 0.6 ~ 1.2 m, and the angle of the core slope can reach 71°. In addition, for the contact surface between the core and the plinth, there are both arc contact and flat contact. In order to facilitate the construction, flat joints are widely used in engineering. In response to the research in this paper, the statistics provide valuable information to understand the valley shape conditions, as well as the structural form of the core. Table 1 Basic information of 20 ACCRDs. No. Dam Country Year Core type H C /m H D /m L C /m T /m W /m Slope gradient Joint type 1 Finstertal Austria 1977 Inclined core 96 150 652 0.5 ~ 0.7 - - Flat contact 2 Maopingxi China 1993 Vertical core 94 105 889 0.5 ~ 1.2 3.0 1 V :1.48 H Arc contact 3 Dong tang China 1996 Vertical core 46 48 145 0.5 1.0 1 V :0.75 H Arc contact 4 Storglomvatn Norway 1997 Vertical core 117 125 825 0.5 ~ 0.9 - 1 V :1.73 H Flat contact 5 Guanmao zhou China 1999 Vertical core 107 109 242.8 0.6 ~ 1.5 3.0 1 V :1.19 H Flat contact 6 Yele China 2001 Vertical core 120 124.5 411 0.6 ~ 1.2 2.4 1 V :1.48 H Flat contact 7 Shimen China 2006 Vertical core 94.5 106 312.51 0.6 ~ 1.2 2.4 1 V :1.07 H Flat contact 8 Guanying dong China 2006 Vertical core 57.7 60 241 0.5 ~ 1.0 2.0 1 V :1.75 H Arc contact 9 Ertang gou China 2007 Vertical core 63 64.3 500 0.5 ~ 1.2 1.2 1 V :1.11 H Flat contact 10 Ba di China 2009 Vertical core 96 98 371 0.8 ~ 1.2 - 1 V :0.78 H Flat contact 11 Kushitayi China 2009 Vertical core 90.9 91.1 439 0.4 ~ 0.8 2.0 1 V :0.65 H Flat contact 12 Huangjing ping China 2011 Vertical core 75.2 85.5 407.44 0.6 ~ 1.1 2.3 1 V :0.58 H Flat contact 13 Quxue China 2014 Vertical core 132 173.2 219.44 0.6 ~ 1.5 3.0 1 V :0.33 H Arc contact 14 Jingfo shan China 2014 Vertical core 104.25 104.85 320.08 0.5 ~ 1.3 3.0 1 V :1.07 H Flat contact 15 Hongyu dong China 2015 Vertical core 100 102.8 219.4 0.8 ~ 1.2 2.0 1 V :0.58 H Flat contact 16 Dashi men China 2016 Vertical core 128.5 130 205 0.6 ~ 1.4 2.6 1 V :0.49 H Flat contact 17 Zongge lu Africa 2018 Vertical core 74 85 130 0.6 ~ 1.0 2.5 - Flat contact 18 Dongtai zi China 2019 Vertical core 42.6 45.83 1505.6 0.5 1.0 - Arc contact 19 Tuo pa China 2019 Vertical core 59.5 61.5 431.42 0.5 ~ 0.7 2.0 1 V :2.05 H Flat contact 20 Jiangjia Kou China 2021 Vertical core 96 98 381 0.6 ~ 1.1 2.2 1 V :1.80H Flat contact 21 Pa zi China 2022 Vertical core 106 107.2 108 0.6 ~ 1.2 2.3 1 V :1.66 H Flat contact 3.2 Calculation scheme Figure 3 shows the four sets of computational schemes designed for this study. For the provisions of the slope ratio of the core, China's water conservancy design code [ 18 ] requires the slope of the ACC to be lower than 1:0.35. Observing the existing dam structure data, this study combines the joint forms (arc joint, flat joint) of the core to adjust the slope of the bank slope to a relatively extreme situation, that is, the slope of the bank slope is 1 V :0.35 H (71°), 1 V :0.25 H (76°), 1 V :0.15 H (81°). The designed scheme fully considers the high-steep conditions of the valley, and on this basis, the asymmetric valley and the symmetric valley are designed as the control group. In addition, the calculation scheme also considers the embedding depth D at the joint, which is 0.1 m, 0.3 m and 0.5 m respectively. And the joint amplification angle θ , 60°, 70°, 80° respectively. In order to understand the influence of joint structure on the mechanical properties of core. 4 Numerical Computation Model 4.1 Finite element model Three-dimensional finite element analysis was carried out using ABAQUS software. The finite element mesh of the dam and the mesh of the core joint are shown in Fig. 4 . There are 51816 units and 59083 nodes in the whole ACCRD. The model is meshed by hexahedral elements, and the joints of the core are properly encrypted. The origin of the calculation coordinate system is located at the intersection of the maximum dam section and the base. The origin of the calculation coordinate system is located at the intersection of the maximum dam section and the base. The river direction is the Y axis, the cross river direction is the X axis, and the vertical direction is the Z axis. The calculation range of foundation is as follows: it extends 172 m upward and downstream along the flow direction, 172 m along the left and right banks along the dam axis direction, and 172 m along the depth direction. In order to reasonably reflect the mechanical properties of the core, four layers of elements are divided along the thickness direction of the core. The bottom of the model is fully constrained and the surrounding normal constraints. Figure 5 is the schematic diagram of the maximum dam section. ACC and rockfill body are filled in the same layer, and gravity load is applied step by step. Combined with the actual water storage process as shown in Fig. 6, considering the permeability of the upstream dam shell material, it is decided to simulate the hydrostatic pressure by vertically acting on the surface of the asphalt core through the 12-level water storage. 4.2 Constitutive model and model parameters In this paper, Duncan Chang E-B material constitutive model is used for rockfill, transition material and ACC. A large number of studies have shown that the stress-strain relationship of asphalt concrete core materials shows obvious nonlinearity [ 20 ] . Duncan Chang E-B model considers the hyperbolic dependence of loading/unloading stress path and elastic modulus on the current stress state, which can well describe the nonlinear behavior of asphalt concrete. At present, Duncan Chang E-B model is widely applied to the numerical simulation of asphalt core dam has accumulated a lot of application experience [ 21 , 22 ] . The material parameters are obtained from the triaxial experiment, and the material parameters are shown in Table 2 . Table 2 Duncan Chang E-B Model Material Parameters. Material ρ (kg/m 3 ) K n R f c (MPa) φ (°) K b m K ur Rockfill material of Ⅰ 2300 900 0.51 0.85 - 47.8 430 0.26 1800 Rockfill material of Ⅱ 2330 1000 0.58 0.84 - 51.3 580 0.47 2000 Asphalt concrete core 2447 287 0.21 0.58 0.3 31.6 1190 0.76 500 Transition layer 2320 1122 0.28 0.72 - 52.1 567 0.06 1800 Note K , modulus of the elasticity coefficient; n , elastic modulus exponent; R f , failure ratio; c , cohesion intercept; φ , friction angle; K b , the bulk modulus coefficient; m , bulk modulus index; K ur , Unloading-reloading elastic modulus base. According to the data collected in reference [ 23 ] , a total of 12 batches of core samples were drilled in the whole construction process of ACC, and the static triaxial experiment was carried out. The test temperature is 15°C, the axial deformation rate is 0.2 mm/min, and the confining pressure is 300, 600, 900, 1200 kPa. Figure 7 shows the static triaxial experiment results of one batch of core samples. The strain softening phenomenon occurs under low confining pressure, and the phenomenon is not obvious when the confining pressure is high. The volumetric strain-axial strain curve shows shear contraction at the beginning, followed by dilatancy; the larger the confining pressure is, the more obvious the shear shrinkage phenomenon is, and the shear dilatancy is obviously weakened. The peak strength increases with the increase of confining pressure. It can be seen from the diagram that the axial compressive strain of ACC sample is 10%~27% when it is destroyed. The linear elastic model is used to simulate the stress-strain relationship of plinth and bedrock. The calculation parameters are shown in Table 3 . Table 3 Linear Elasticity Material Parameters. Material ρ (kg/m 3 ) E (MPa) ν Concrete base 2400.00 30000.00 0.167 Bedrock 2100.00 3300.00 0.250 Note: ρ , density; E , Elastic moduli; ν , Poisson’s ratio. The Goodman contact element is used to simulate the stress and deformation of the contact surface between the transition layer and the ACC. The contact parameters are shown in Table 4 , and the constitutive relationship of the contact surface is as follows [ 24 ] : $$\left\{ {\begin{array}{*{20}{c}} {\Delta {\tau _1}} \\ {\Delta {\tau _2}} \end{array}} \right\}{\text{=}}\left[ {\begin{array}{*{20}{c}} {{k_{s1}}}&0 \\ 0&{{k_{s2}}} \end{array}} \right]\left\{ {\begin{array}{*{20}{c}} {\Delta {\gamma _1}} \\ {\Delta {\gamma _2}} \end{array}} \right\}$$ 4 Where k s1 and k s2 are the tangential contact stiffness expressions as: $${k_{s1}}{\text{=}}{\left( {1 - {R_f}\frac{{{\tau _1}}}{{{\sigma _n}\tan \delta }}} \right)^2}{K_1}{\gamma _w}{\left( {\frac{{{\sigma _n}}}{{{p_a}}}} \right)^n}$$ 5 $${k_{s2}}{\text{=}}{\left( {1 - {R_f}\frac{{{\tau _2}}}{{{\sigma _n}\tan \delta }}} \right)^2}{K_2}{\gamma _w}{\left( {\frac{{{\sigma _n}}}{{{p_a}}}} \right)^n}$$ 6 Table 4 Calculation parameters of Goodman interface model. Contact surface R f K 1 K 2 n δ (°) c (kPa) Between the core And transition layer 0.82 2600.00 5000.00 0.48 30.00 23.00 Between the core and concrete cushion block 0.85 6000.00 20000.00 0.30 20.00 100.00 Between rockfill materials and concrete cushion block 0.86 2800.00 5500.00 0.35 10.00 100.00 Note: K 1 , K 2 , n , R f , nonlinear contact parameters, determined by experiment; δ , contact surface friction angle. γ w , water density; P , atmospheric pressure. 4.3 Comparison of measured data and computed results In order to better verify the calculation model of this study, combined with the measured data from the strain and deformation to prove the rationality of the numerical model. The monitoring information is the local vertical strain measured in the core after reservoir impoundment in November 2017, and combined with the monitoring data [ 25 ] , it can be found that the trend of the strain between the computed results and the measured results is close as shown in Fig. 8(a). According to the measured data, the vertical strain of the upstream surface of the core is compressive strain and less than about 4.0%. The overall trend shows that the higher the elevation, the smaller the compressive deformation. The finite element calculation shows that the whole section of the core is compressed, the large compressive strain is mainly concentrated on the side near the gentle bank slope, and the vertical compressive strain is about 2% at the bottom. The computed maximum value is slightly smaller than the monitoring value, but the calculated values of other elevations are very close to the measured values. The monitored and calculated values are less than the compressive strain obtained from the triaxial experiment (Fig. 7). Figure 8(b) compares the calculated and measured lateral displacement of the core A section at four different water levels. According to the actual water storage process [ 26 ] , the water storage began from el.2208 m on February 12, 2017. On March 15, the water level reached el.2280 m and rose by 72 m in 31 days. On April 13, it reached el.2310 m, up 30 m from the previous stage. The subsequent water level rose slowly, reaching el.2320 m on June 7 and rising to el.2327 m on November 19. The whole water storage process lasted for 9 months. In order to ensure the calculation accuracy, this water storage process is well reflected by the analysis step of the software. Combined with the actual measurement results, it can be found that the trend of the core's lateral displacement along the elevation shows an increase and then decrease. With the increase of water level, the displacement along the river increases obviously. The finite element simulation results show the same variation curve as the measurement results. However, the numerical simulation results are larger than the measurement results by 2 ~ 3 cm, which is within a reasonable range and confirms the accuracy of the simulation results. Figure 9 shows the layout of the engineered water level meter, and compares the measured and detected dam deformation. Five settlement points are arranged in the cross section B at el.2244 m, and the vertical settlement of the dam is measured by water level gauge( WLG ). The settlement distribution and size of the el.2244 m measuring point are recorded when the dam rises from el.2289 m to el.2334.2 m. The computed deformation mode is roughly the same as the monitoring data. In summary, the calculation model in this paper can accurately reflect the mechanical properties of ACCRD. 5 Results and Discussion 5.1 Influence of narrow valley on the stress of ACC Under the condition of high-steep bank slope, the shear effect and arching effect of core can’t be ignored. Figure 10 shows the distribution of stress level. It can be found that the distribution of stress level in the completion period and the impoundment period is very similar. The stress level in the impoundment period is slightly higher than that in the completion period, and the dam body has two areas with high stress level. One appears near the upstream contact surface between the dam body and the core, with a large range and a high stress level. There are two reasons for the high stress level in this area. First, the modulus difference between the core and the dam rockfill is large, resulting in large uneven settlement in the area, resulting in large shear deformation. Second, under the action of water pressure, the deformation of the core to the downstream causes the small principal stress σ 3 in this area to decrease greatly, which makes the stress level increase [ 27 ] . However, the direction of shear deformation points to the inside of the dam body, which will not affect the stability of the upstream dam shell. Another area with high stress level in the dam is the contact part between the dam and the bank slope. It can be found that the stress level at the steeper position of the bank slope is relatively high, and the maximum dislocation displacement is 3.62 cm. This is due to the steep slope, the dam and the core will produce large shear deformation along the slope direction. At the same time, under the action of water pressure, the core will also undergo shear deformation downstream. Therefore, it is necessary to pay attention to the shear stress level of the core during the impoundment period. Figure 11 shows the contour distribution of tensile stress and shear strain of the core. Combined with Fig. 11(a), it can be found that from completion to impoundment, the tensile stress of the core increases, and the maximum tensile stress reaches 0.54 MPa, which is located at the end of the left bank of the core. In this process, the tensile area of the core is always concentrated at the top. However, it is worth noting that the tensile area and tensile stress on the right bank are significantly smaller than those on the left bank. This is because the right bank slope shows a trend of slowing down from the top to the bottom, which makes the tensile stress concentrate in a steeper section. Combined with the shear strain in the XZ direction in Fig. 11(b), it is further understood that the shear strain in the impoundment period is also larger than that in the completion period. At the same time, it can be found that the length of the potential slip zone on the right bank is longer than that on the left bank, where the compressive strain is on the slow side (the right bank side); the tensile strain is located on the steep side (the left bank side), and the maximum value is 1.69%, which is located at about 1/5 dam height of the left bank slope. This is because the steeper the bank slope, the greater the component force along the slope. Figure 12 shows the stress reduction of the core during the completion period and the impoundment period. Combined with Fig. 12(a), it can be found that the distribution of the arching coefficient R in the completion period and the impoundment period is not much different, and there is obvious aggregation near the slope on both sides. For such 'V' type valleys, under the condition of high-steep bank slopes, the arching coefficient R near the upper bank slope of the core is significantly reduced, indicating that the stress transfer between the core and the surrounding soil is obvious, resulting in a strong arching. But the difference is that the arching in the completion period is obviously weaker than that in the impoundment period. This is mainly due to a certain degree of increase in the vertical stress of the core under water presssure, and the results are similar to those in the reference [ 28 ] . It can be found from Fig. 11b that compared with the completion period, the change of stress caused by the impoundment period is dominant, and the strain has no significant change. In addition, after impoundment, the arching coefficient R does not change much with the reservoir water level, and most of them are within 10%, indicating that the arching during the construction period plays a decisive role in the arching after impoundment. Therefore, more attention should be paid to the arching during the completion period [ 29 ] . 5.2 Influence of joint form under asymmetric valley condition Figure 13 shows the variation law of arc joint and flat joint core stress level under different bank slope gradients. The research object comprehensively considers the actual terrain conditions (V-shaped valley, steep bank slope, asymmetry). Here, the dam height and the size of the bottom base are kept unchanged, and the slope of the steep bank slope on the left bank is adjusted, which can be analogized to widening the length of the dam axis. The calculation results show that as the slope of the left bank becomes steeper, the stress level and shear stress S 13 component of the core decrease. The maximum stress level is located in the left bank near the bottom area, and there is also a large area of high stress level in the middle of the right bank, which is consistent with the conclusion of the reference [ 30 ] . The rock on the left bank is steep and the core has a large misalignment along the bank slope. As the bank slope slows, the component force of gravity on the soil above the unit length becomes larger, resulting in an increase in shear stress S 13 downslope. In order to compare the differences in stress level contour distributions between the two joint forms more intuitively, the areas with S > 0.24 are shaded according to the calculation results. It is worth noting that the stress level of the whole joint of the arc joint is higher than that of the flat joint, and the overall stress level of the arc joint core is also higher than that of the flat joint core. This is because the arc joint is embedded inside the plinth, and under the action of water load, the embedded part restricts the deformation of the core. In the asymmetric V-shaped steep valley, the stress of the arc contact surface is not uniform, and the local extrusion deformation is large. The uncoordinated deformation leads to a large stress mutation in the convex part of the arc contact surface, especially in the middle of the contact surface. Figure 14 shows the variation law of arc joint and flat joint core arching with different bank gradients. It was pointed out that when the vertical stress in the core is 20%-50% of the vertical stress in the adjacent soil material at the same elevation, cracks may occur in the core. In order to analyze the law of stress transfer more intuitively, take 0.2 as the limit of the arching coefficient R , and find the percentage of the area of the whole core area when the arching coefficient R is lower than 0.2 [ 16 ] . The results show that in the asymmetric V-shaped valley, as the bank slope slows down, the area percentage corresponding to R less than 0.2 and the shear strain increase, and the stress transfer of the core increases. The arching on the left bank slope and the top of the right bank slope is the strongest. The largest arching area accounts for 8.64%, and the corresponding maximum E XZ is 1.4%. Taking the left bank side as an example, the arching coefficient R decreases and then increases along the left bank slope. It is worth noting that the arching of the arc joint core is higher than that of the flat joint. Although the overall arching distribution position of the two is similar, the low stress area of the arc joint extends to the top of the core. The reason is that the high stress level area of the arc joint core extends along the slope to the top of the core. 5.3 Influence of joint form under symmetric valley condition Figure 15 is the stress level variation law of the arc joint and the flat joint core under different bank slope gradients in the symmetrical valley. Combined with Fig. 15(a), it can be found that the stress level of the core is a process of 'increase-decrease-increase-decrease' along the elevation. Compared with the asymmetric valley, the maximum stress level in the symmetric valley is located at the bottom of the core, and the maximum stress level in the asymmetric valley is located on the side of the steep bank slope near the bottom. This is because the stress level in this paper reflects the overall shear characteristics of the core. The vertical extrusion at the bottom of the symmetrical valley core and the thrust along the river are the largest, and there is a large deformation. Of course, the stress level S near the bottom of the core axis is relatively large about 0.3. This is attributed to the distribution characteristics of the principal stress σ 3 of the core. The sharp decrease of the minor principal stress σ 3 at the bottom of the core will lead to a significant increase in the stress level. In other words, the symmetry of the valley will lead to stress deflection and affect the shear stress S 13 characteristics of the core. The symmetrical valley can evenly distribute its own gravity along the slope direction. On the whole, the maximum stress level S and shear stress S 13 of the core are increasing with the bank slope steepening. The maximum stress level S and shear stress S 13 of the arc joint core are greater than those of the flat joint core, and the maximum stress level S = 0.47 and shear stress S 13 = 554.8 kPa, as shown in Fig. 15(b). The above results show that the shear characteristics of arc joint core are more sensitive to the change of bank slope. For the symmetrical valley, the shear effect of the flat joint core is weak, and the adaptability to the steep bank slope will be better. Figure 16 shows the variation law of arc joint and flat joint core arching under different bank slope gradients in symmetrical valley. The calculation results show that the arching coefficient R at the central axis of the core is 'decrease-increase-decrease-increase' along the elevation. The arching in the middle and upper part of the core is strong, and its change trend is opposite to the change trend of the stress level S along the elevation. It shows that the shear effect is enhanced, the arching of the core is enhanced, and the two are closely related. Combined with the contour map Fig. 16(a), it can be found that the area with arching coefficient R < 0.2 is located on the slope side of both banks and extends to the top of the dam, which is symmetrically distributed. According to the shear stress contour map in Fig. 15(b), it is well verified that the shear stress on the slope side of the core is obviously stronger than that in other areas. This shear stress will prevent the settlement of the core, so that part of the vertical deformation of the core will be transferred to the harder bedrock, resulting in tensile areas on both sides and at the top of the core. The maximum tensile stress is 443.7 kPa, which is located at the top of the core, as shown in Fig. 16(b). On the whole, the bank slope becomes steeper, the percentage of the area where the arching coefficient is less than 0.2 increases, and the arching of the core is increasing. The area proportion of the arc joint core R < 0.2 corresponding to the slope of 1:0.15, 1:0.25, 1:0.35 is 7.4%, 6.49% and 5.58% respectively. The flat joint core is 7.03%, 6.04% and 5.09% respectively. Similarly, the arching and tensile stress of the arc joint core are higher than those of the flat joint core. The above results show that the shear action of the core will cause the stress redistribution of the core, and for the symmetrical valley, the arching of the flat joint core under the condition of steep bank slope is relatively low. 5.4 Influence of joint embedment depth Figure 17 shows the overall distribution law of core stress level under different embedded depths of joints. The calculation results show that the core maximum stress level S and the core maximum shear stress S 13 increase with the increase of the the core joint embedded depth D . The maximum stress level S = 0.35 and the shear stress S 13 = 452.3 kPa are higher than the flat joint core. In addition, the maximum value of shear stress S 13 occurs at the shoulder of the core, as shown in Fig. 17(a). Due to the symmetrical distribution of stress level contours, the right bank side of the core is taken for analysis. It is worth noting that the stress level is higher in three regions, namely: the bottom of the core, the slope of the core near the bottom, and the middle and upper part of the core, in which the maximum value of the stress level occurs at the bottom of the core, as shown in Fig. 17(b). This is the same as the calculation results of reference [ 24 ] . The shear dislocation deformation at the shoulder of the core is the largest, reaching 37.8 mm, and the bottom of the core reaches 2mm. For the stress level S at the characteristic position (excluding the high stress level area at the shoulder and the bottom of the core), the shear effect is the strongest, at about 1/3 H from the bottom. Combined with the distribution of the stress level of the core in different directions, the above rules (as shown in Fig. 18) are further elaborated. The measuring line transits from the central axis A-A of the core to the C-C of the bank slope, as shown in Fig. 18(a). The stress level S at the bottom and top of the measuring line are significantly different. The stress level S in the upper and middle parts of the core and most of the bottom areas are high. On the C-C side of the core bank slope, with the increase of the embedding depth D , the stress level S in the middle and lower part of the core increases. This may be because the embedded depth increases under the action of water load, and the constraint effect of the core wall becomes larger. Figure 18(b) shows the distribution of the core stress level along the longitudinal direction. It can be found that the stress level on both sides of the bank slope is first higher than the middle region and gradually decreases to lower than the middle region as the height increases. Compared to other areas of the core, the core joints are the most sensitive to stress changes. This is due to the fact that the contact surface is made up of two materials with huge differences in stiffness, and there will be significant shear action at such interfaces of soft and hard contact. For the core as a whole, the increase of embedding depth will enhance the local shear effect of the core. Figure 19 shows the distribution law of core arching coefficient in different directions under different embedded depths of joints. It can be found that with the change of joint type, the difference of core stress behavior is mainly concentrated on the bank slope side. Combined with Fig. 19(a), taking the core right bank slope as an example, as the embedding depth of the core increases, the arching coefficient in the middle and lower parts of the core decreases, indicates that the arching of the core increases, which corresponds to the distribution law of the core stress level. Overall, the percentage of the area where the core arching coefficient R is less than 0.2 does not change much. The values corresponding to D = 0.1, 0.3 and 0.5 m are 5.1%, 5.12% and 5.2%, respectively. When the core’s shape structure does not change much, it is more likely to affect the local stress state of the core. As shown in Fig. 19(b), it can be concluded from analyzing the stress transfer in the core at the same elevation that the stress transfer on the bank slope side of the core is significantly higher than that in the middle of the core, and the arching coefficient decreases dramatically near the bank slope. 5.5 Influence of joint amplification angle Figure 20 shows the stress level and shear stress distribution of the core under different joint magnification angles. The maximum stress level S corresponding to θ = 60 °, θ = 70 ° and θ = 80 ° are 0.33, 0.35 and 0.40, respectively. The shear stress S 13 increases from 290.5 kPa to 349.3 kPa, which is within the allowable shear strength range. With the increase of the angle, the maximum value of the overall stress level and the maximum shear stress of the core are increasing. Based on the stress level contour map, it can be found that the stress level at the bottom, middle and upper parts of the core and the slope side of the core are higher, as shown in Fig. 20(a). The distribution law of stress level along the right bank slope of the core can well explain the above phenomenon. In general, the distribution law of stress level along the elevation is consistent. The stress level at the top of the arc joint core is the largest. With the increase of the joint amplification angle, the stress level on the side of the bank slope is also increasing. The distribution law of stress level S along the right bank slope of the core can well explain the above phenomenon. In general, the distribution law of stress level S along the elevation is consistent. The stress level S at the top of the arc joint core is the largest. With the increase of the joint amplification angle, the stress level S on the side of the bank slope is also increasing, as shown in Fig. 20(b). In order to better explain the shear mechanism of the joint, flat joints with different magnification angles were further set up. The results show that there is a significant difference in the distribution of the stress level along the elevation of the right bank slope of the arc joint and the flat joint core, which is mainly reflected in the middle and lower regions and the top of the core. Taking 80 m elevation as the boundary, the stress level of the flat joint increases first and reaches the first peak near 30 m. The stress level of the middle and lower part of the right bank slope of the flat joint core is higher than that of the arc joint core. For flat joints, expanding the contact surface can reduce the stress level. The angle decreases and the contact surface expands, which can reduce the stress level. Figure 21 is the distribution law of core arching coefficient under different joint magnification angles. The effect of the joint magnification angle change on the overall arching of the core was not significant (as shown in Fig. 21(a)), and the percentage of area corresponding to arching coefficient R < 0.2 stabilized at 5.12%, which was concentrated near the core slope. As shown in Fig. 21(b), the arching coefficient R at the bank slope of the core gradually decreases from the bottom to the top, and the arching coefficient R at the bank slope is less than 0.5. It is worth noting that compared with the arc joint, the arching coefficient R on the bank slope side of the flat joint core varies greatly. It can be seen that the smaller the angle, the lower the arching coefficient R of the slope side of the core. 6 Conclusion Based on numerical analysis, this study first analyzes the adaptability of arc joints and flat joints to different types of steep slope valleys (asymmetric valleys and symmetric valleys). On this basis, the shear law of ACC is deeply analyzed in terms of the core embedment depth and the core amplification angle. The main conclusions are as follows: (1) Under the condition of high and steep bank slope, there is a large shear deformation of ACC. The stress level near the steep bank slope is high, which produces a significant arching, and the arching coefficient is less than 0.5. The tensile stress zone is concentrated on the shoulders of the core, and the maximum tensile stress reaches 0.54 MPa. (2) For the asymmetric V-shaped valley, adjusting the slope of the steep bank slope on one side, the bank slope becomes steeper, the length of the dam axis is shortened, the overall stress level of the core and the arching are reduced, and the structure of the multi-section slow bank slope can well alleviate the shear effect; compared with the flat joint, the stress level of the arc joint of the core is concentrated, and the arching is strong. (3) The symmetry of the valley will lead to the deflection of the stress and affect the shear stress characteristics of the core. Under the condition of symmetrical valley, the maximum stress level is located at the bottom of the core, and the shear effect and arching of the core with steep slope are enhanced. The shear characteristics of the arch joint core are highly sensitive to the change of slope gradient, and the overall stress level and arching of the arch joint core are higher than those of the flat joint. (4) Increasing the embedding depth of the joint will enhance the local shear effect of the core. The stress level of the core ranges from 0.3 to 0.4. When D = 0.5 m, the core S max = 0.35, and the maximum shear stress is 452.3 kPa, which appears at the shoulder of the core. (5) As the angle of the core joint decreases, the maximum stress level of the core and the maximum shear stress decrease by 17%. The stress levels corresponding to θ = 80°, θ = 70°, and θ = 60° are 0.20, 0.16 and 0.14, respectively. Expanding the contact surface of the joint can reduce the stress level. Declarations Author Contribution Yong Li: Conceptualization, Methodology, Validation, Writing-review & editing.Yanlong Li: Formal analysis, Supervision, Funding acquisition.Yunhe Liu: Funding acquisition.Xinjian Sun: Investigation and Validation.Lifeng Wen: Formal analysis.Weimei Li: Acquisition of data. Acknowledgments The work was supported by the National Natural Science Foundation of China (Grant No. 52039008); the China National Funds for Distinguished Young scientists (Grant No. 52125904); the National key R&D plan (Grant No. 2022YFC3004403); the Program 2022TD-01 for Shaanxi Provincial Innovative Research Team (No. 2022TD-01). Data Availability Statement The date used to support the findings of this study are available from the corresponding author upon request. 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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-3988129","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":276038914,"identity":"f4f74e12-d5fc-4058-8193-ed2815b846a3","order_by":0,"name":"Yong Li","email":"","orcid":"","institution":"Xi’an University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Yong","middleName":"","lastName":"Li","suffix":""},{"id":276038915,"identity":"6bcb397b-ea72-44a3-b208-b4b4164d791c","order_by":1,"name":"Yanlong 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8","display":"","copyAsset":false,"role":"figure","size":86434,"visible":true,"origin":"","legend":"\u003cp\u003eComparison between the measured results and core monitoring data.\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/49da1b033fc5f394be171f0f.png"},{"id":52101666,"identity":"b230c8da-7abb-449e-bdb5-d0d76fd1116e","added_by":"auto","created_at":"2024-03-06 19:09:36","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":36215,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of the measured and computed vertical settlement at el.2244 m (section B).\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/3a39cf83bada92f88ff38615.png"},{"id":52101239,"identity":"8310d0ad-df5f-4f94-80a0-a6f857c7e2ef","added_by":"auto","created_at":"2024-03-06 19:01:36","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":168849,"visible":true,"origin":"","legend":"\u003cp\u003eStress level distribution diagram.\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/36ba67fa31faf0e26a9ff843.png"},{"id":52101251,"identity":"12b56fba-9837-470c-9888-53a9c3fb1bac","added_by":"auto","created_at":"2024-03-06 19:01:37","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":61213,"visible":true,"origin":"","legend":"\u003cp\u003eCore stress-strain distribution contour map\u003c/p\u003e","description":"","filename":"11.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/4ed1e430918e0becf3833f5d.png"},{"id":52101245,"identity":"8709e10d-b84a-4b29-91f2-6a7d1e7315de","added_by":"auto","created_at":"2024-03-06 19:01:36","extension":"png","order_by":12,"title":"Figure 12","display":"","copyAsset":false,"role":"figure","size":74717,"visible":true,"origin":"","legend":"\u003cp\u003eStress reduction of core.\u003c/p\u003e","description":"","filename":"12.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/cf73a369eec2cd2ad236d18d.png"},{"id":52101254,"identity":"eb75b7de-40f9-4c4d-b694-3eab7354aa53","added_by":"auto","created_at":"2024-03-06 19:01:37","extension":"png","order_by":13,"title":"Figure 13","display":"","copyAsset":false,"role":"figure","size":82499,"visible":true,"origin":"","legend":"\u003cp\u003eThe variation law of stress level and shear stress (\u003cem\u003eS\u003c/em\u003e13) of core with different bank gradients.\u003c/p\u003e","description":"","filename":"13.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/1934ce82ac901d9b1b4423de.png"},{"id":52101250,"identity":"0b78742d-68f6-4bd4-a4cf-7766a544b098","added_by":"auto","created_at":"2024-03-06 19:01:36","extension":"png","order_by":14,"title":"Figure 14","display":"","copyAsset":false,"role":"figure","size":83184,"visible":true,"origin":"","legend":"\u003cp\u003eThe arching and shear strain \u003cem\u003eE\u003c/em\u003e\u003csub\u003e\u003cem\u003eXZ\u003c/em\u003e\u003c/sub\u003e variation law of core with different bank slope gradients.\u003c/p\u003e","description":"","filename":"14.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/9caff016325b514783a79930.png"},{"id":52101244,"identity":"1ab6f3c8-0320-4578-9aa1-2f01a4b4c3b9","added_by":"auto","created_at":"2024-03-06 19:01:36","extension":"png","order_by":15,"title":"Figure 15","display":"","copyAsset":false,"role":"figure","size":77472,"visible":true,"origin":"","legend":"\u003cp\u003eThe variation law of core stress level in symmetrical valley with different bank slope gradients.\u003c/p\u003e","description":"","filename":"15.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/84b0d59b8e961614995c2b0d.png"},{"id":52101242,"identity":"d8587cce-9ae8-4b61-a9df-9f0c1657340f","added_by":"auto","created_at":"2024-03-06 19:01:36","extension":"png","order_by":16,"title":"Figure 16","display":"","copyAsset":false,"role":"figure","size":73455,"visible":true,"origin":"","legend":"\u003cp\u003eThe variation law of core arching with different bank slope in symmetrical valley.\u003c/p\u003e","description":"","filename":"16.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/18df68cb3bda81bb3d5d13fa.png"},{"id":52101667,"identity":"0861946a-ece0-47ca-bab1-a83b37191292","added_by":"auto","created_at":"2024-03-06 19:09:36","extension":"png","order_by":17,"title":"Figure 17","display":"","copyAsset":false,"role":"figure","size":155889,"visible":true,"origin":"","legend":"\u003cp\u003eThe overall distribution law of core stress level and shear stress under different embedded depths of joints.\u003c/p\u003e","description":"","filename":"17.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/2991b6c4253a275922fa39c0.png"},{"id":52101247,"identity":"c5338942-c6b6-4edd-978d-a4e3c186b8fd","added_by":"auto","created_at":"2024-03-06 19:01:36","extension":"png","order_by":18,"title":"Figure 18","display":"","copyAsset":false,"role":"figure","size":165296,"visible":true,"origin":"","legend":"\u003cp\u003eThe distribution law of core stress level in different directions under different joints' embedded depths.\u003c/p\u003e","description":"","filename":"18.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/983b161194e14dd6011bcbe3.png"},{"id":52101253,"identity":"03256138-333a-4942-9002-b9c3ab8e1156","added_by":"auto","created_at":"2024-03-06 19:01:37","extension":"png","order_by":19,"title":"Figure 19","display":"","copyAsset":false,"role":"figure","size":140320,"visible":true,"origin":"","legend":"\u003cp\u003eDistribution law of core arching coefficient in different directions.\u003c/p\u003e","description":"","filename":"19.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/e6418b45b2f7b0bced9fb18b.png"},{"id":52101668,"identity":"2a5a8b44-0e8d-42ae-bfa0-f96d8ac67688","added_by":"auto","created_at":"2024-03-06 19:09:36","extension":"png","order_by":20,"title":"Figure 20","display":"","copyAsset":false,"role":"figure","size":137277,"visible":true,"origin":"","legend":"\u003cp\u003eStress level distribution law of core with different amplification angle.\u003c/p\u003e","description":"","filename":"20.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/339ce74b60a8aaffe06a845d.png"},{"id":52101249,"identity":"7e09b5e9-c83f-49a8-ac33-6ce0a6a86bdf","added_by":"auto","created_at":"2024-03-06 19:01:36","extension":"png","order_by":21,"title":"Figure 21","display":"","copyAsset":false,"role":"figure","size":55795,"visible":true,"origin":"","legend":"\u003cp\u003eDistribution law of core arching coefficient under different joint magnification angles\u003c/p\u003e","description":"","filename":"21.png","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/49e0fbebd30a96e08b05500d.png"},{"id":56156520,"identity":"6adebb67-ed7f-47ec-89cb-5ed05cc579e8","added_by":"auto","created_at":"2024-05-09 08:22:39","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3566483,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3988129/v1/dd5ea71a-b98a-475c-b51c-5aa0c015b030.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Influence of joint form on shear characteristics of asphalt concrete core under steep bank slope condition","fulltext":[{"header":"1 Introduction","content":"\u003cp\u003eIn recent years, more and more dams choose asphalt concrete core rockfill dams (ACCRDs) because of their strong adaptability to deformation and good plasticity\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. Under the condition of high-steep bank slope, the joint part of ACC and plinth may have large shear deformation, which seriously endangers the impermeability and safety of dam body and core\u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e. Therefore, it is of great significance to study the shear stress law of the joint of ACC under the condition of high - steep bank slope\u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e, which is of great guiding significance to the construction of 100-meter-class ACCRD.\u003c/p\u003e \u003cp\u003eAt present, the research on the shear characteristics of ACC by scholars at home and abroad is mainly summarized into two aspects, namely model test and numerical simulation. On the one hand, in the model experiments, the mechanical properties of the core are mainly studied by the shear effect of the two interfaces\u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. Tajdini et al. (2014)\u003csup\u003e[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e considered the interface between mortar and asphalt concrete under dry and saturated conditions. Through small-scale direct shear tests, the effects of asphalt permeability grade, moisture and density on shear strength under different normal stress levels and constant shear rates were carried out. Wang et al. (2018)\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e carried out shear tests on the interface between ACC and transition layer, and studied and evaluated the behavior of shear displacement between the two. As shown in Fig.\u0026nbsp;1, another type is the connection between the ACC and the concrete structure, which belongs to the soft asphalt-rigid concrete interface. Wang et al. (2010)\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e conducted a special model test to study the connection behavior between the narrow asphalt core and the plinth. The results of the water storage test showed that the seepage through the ACC and the core - plinth interface was very small. Kong et al. (2013)\u003csup\u003e[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e obtained that the inclination of the core of the arc joint type is slightly larger than that of the horizontal joint type through the shaking table model analogy test. Wang et al. (2017)\u003csup\u003e[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]\u003c/sup\u003e proposed to embed a row or two rows of water stops in the plinth to strengthen the connection of the asphalt core plinth when studying the optimal ratio of SAM at the connection between the core and the plinth. The existing model test is limited to small size, failing to consider the overall structure of the core, and failing to fully reflect the evolution law of the overall stress and deformation of the core.\u003c/p\u003e \u003cp\u003eOn the other hand, in the numerical analysis, Li et al. (2023)\u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e combined with the reliability theory to analyze the crack resistance reliability of ACC under the action of water storage. The calculation results show that there is tensile stress concentration near the slope of both sides of the core, but the generation of tensile stress has not been further studied. It is worth noting that there is often a close relationship between the generation of tensile stress and shear action. Based on numerical calculation, Li et al. (2023)\u003csup\u003e[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e quantitatively studied the arch effect mechanism of ACC under complex topographic and geological conditions. The study shows that there is a significant shear effect between the core and the bank slope due to the constraints of the valley terrain. In order to quantify the magnitude of shear action, Gao et al. (2019)\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e proposed the shear safety control standard of ACC based on the stress characteristics of ACC in different periods. In general, the current research on ACCRDs at home and abroad is mainly aimed at the general valley terrain, and there are few studies on the impermeability and safety of the joint between the asphalt core and the base under the condition of high-steep bank slopes. Therefore, it is necessary to consider the condition of high - steep bank slope and carry out the research on the shear action law of ACC and base joint.\u003c/p\u003e \u003cp\u003eIn this study, based on the finite element method, this study first compares and analyzes the adaptability of arc joints and flat joints to different types (asymmetric valleys, symmetrical valleys) of steep slope valleys. On this basis, the stress deformation law of the ACC joint under the condition of steep bank slope is deeply analyzed in terms of the embedded depth and the magnification angle. Revealing the seepage resistance and safety of the dam body and core after shear deformation occurs at the joint areas of steep bank slope. To clarify the applicability of high ACCRDs with steep bank slope, with a view to providing a deeper understanding of the shear deformation of the core of ACCRDs, and to provide some references for practical projects.\u003c/p\u003e "},{"header":"2 Feasibility study on shear behavior of core-plinth","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Core-plinth stress characteristics\u003c/h2\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e2\u003c/span\u003e is the stress diagram of asphalt concrete core - plinth. The AACC is buried inside the rockfill body, and the stress is complex. Its mechanical properties need to comprehensively consider the combined effects of its own load (self-weight) and surrounding structures (friction, earth pressure, water load, etc.)\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e. When analyzing the mechanical properties of ACC, it is necessary to comprehensively consider the combined effect of transition layer and rigid contact. The connection between ACC and concrete concrete structure belongs to soft asphalt-rigidity. Because soft - hard contact is in two areas of different materials and deformation ability, there will be obvious shear effect, and shear stress will be generated at the interface, among which the stress at the junction is more concentrated. During the construction and operation of the dam, the ACC may have a large shear displacement at the joint of the steep bank slope, and it is easy to produce tensile stress and lead to tensile failure at the shoulder of the high and steep bank slope. This requires that the ACC has a large deformation capacity at the joint of the steep bank slope to prevent shear and tensile failure. When the valley terrain is narrow valley, both sides of the valley bank slope is relatively stable and strong structure. The core extrudes and deforms toward the middle of the valley, and the bank slope provides a stable arch footing for the core stress arching\u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. Reasonable quantification and mitigation of shear stress is the focus of research.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Measuring the load capacity\u003c/h2\u003e \u003cp\u003eAt present, the most common method to determine whether the shear failure of ACC occurs is to calculate the ratio of shear stress to failure shear stress, that is, to solve the stress level. The detailed expression is shown in Eq.\u0026nbsp;(\u003cspan refid=\"Equ1\" class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/sup\u003e. The stress level is an important index to judge the limit equilibrium zone in the dam body, and the stress level reflects the degree of strength of the dam material. If the stress level of each part of the dam is less than 1.0, the dam will not be sheared.\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ1\" name=\"EquationSource\"\u003e\n$$S=\\frac{{{\\sigma _1} - {\\sigma _3}}}{{{{({\\sigma _1} - {\\sigma _3})}_f}}}=\\frac{{({\\sigma _1} - {\\sigma _3})(1 - \\sin \\varphi )}}{{2c\\cos \\varphi +2{\\sigma _3}\\sin \\varphi }}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e1\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere \u003cem\u003eS\u003c/em\u003e is stress level; \u003cem\u003eσ\u003c/em\u003e\u003csub\u003e1\u003c/sub\u003e is major principal stress; (\u003cem\u003eσ\u003c/em\u003e\u003csub\u003e1\u0026minus;\u003c/sub\u003e\u003cem\u003eσ\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e\u003cem\u003ef\u003c/em\u003e\u003c/sub\u003e is limit principal stress difference; \u003cem\u003ec\u003c/em\u003e is cohesion; \u003cem\u003eφ\u003c/em\u003e is angle of internal friction.\u003c/p\u003e \u003cp\u003eDuring the impoundment period, the lateral deformation of the core increases under the action of horizontal water pressure, the axial elongation of the core increases, and the tensile strain increases, resulting in an increase in tensile stress. The ACC is very thin compared with the rockfill material, and its tensile strength is generally between 0.19\u0026thinsp;~\u0026thinsp;0.78 MPa. Through the tensile test, the tensile strength of ACC in Quxue Hydropower Station reaches 0.60 MPa. When the calculated maximum tensile stress \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\sigma _{\\hbox{max} }}\\)\u003c/span\u003e\u003c/span\u003e is greater than the tensile strength \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\({\\sigma _t}\\)\u003c/span\u003e\u003c/span\u003e of the core, it is proved that the core is fractured and cracks are generated. The corresponding relation is shown in expression (2).\u003cdiv id=\"Equ2\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ2\" name=\"EquationSource\"\u003e\n$${\\sigma _{\\hbox{max} }} \\leqslant {\\sigma _t}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e2\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eIn the case of narrow valley, there is a strong shear between the core and the rock on both sides, resulting in the transfer of stresses, and the core will produce a significant arching action. The magnitude of the arching can be described by the arching coefficient, which is defined as the ratio of the vertical stress in the cell \u003cem\u003eσ\u003c/em\u003e\u003csub\u003eZ\u003c/sub\u003e to the self-weight of the soil bar on the cell \u003cem\u003eγh\u003c/em\u003e, as shown in Eq.\u0026nbsp;(\u003cspan refid=\"Equ3\" class=\"InternalRef\"\u003e3\u003c/span\u003e)\u003csup\u003e[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e. Some researchers believe that horizontal cracks may occur in the core when the vertical stress of the core is 20% -50% of the vertical stress of the adjacent dam shell at the same elevation\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e.\u003cdiv id=\"Equ3\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ3\" name=\"EquationSource\"\u003e\n$$R=\\frac{{{\\sigma _Z}}}{{\\gamma h}}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e3\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere \u003cem\u003eσ\u003c/em\u003e\u003csub\u003ez\u003c/sub\u003e is vertical stress; \u003cem\u003eγ\u003c/em\u003e is unit weight; \u003cem\u003eh\u003c/em\u003e is the thickness of the soil above the element calculated. The smaller the arching coefficient, the stronger the arching. When the arching coefficient is less than 1, it indicates that the stress is being transferred from the core to the transition layer as well as the dam shell.\u003c/p\u003e \u003cp\u003eTherefore, based on the above analysis, in order to more intuitively compare the safety of the core, we mainly introduce the above three criteria for the mechanical properties of the asphalt concrete core.\u003c/p\u003e \u003c/div\u003e"},{"header":"3 Engineering case and calculation scheme","content":"\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Engineering case\u003c/h2\u003e \u003cp\u003eStatistics show that nearly 200 ACEDs have been constructed. Some typical examples of ACEDs are the 125-meter-high Storglomvatn dam, the 125-meter-high Yele dam and the 85-meter-high Feistritzbach dam. Some of them are more than 150 meters high, 153 meters high Zarema dam. The dam built in 2017 in China is 174 meters high, which is the highest ACCRD in the world\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e lists the data of 20 typical ACCRDs in the world, where \u003cem\u003eH\u003c/em\u003e\u003csub\u003eC\u003c/sub\u003e is the height of the core, \u003cem\u003eH\u003c/em\u003e\u003csub\u003eD\u003c/sub\u003e is the maximum dam height corresponding to the location of the core, \u003cem\u003eT\u003c/em\u003e is the thickness of the core, \u003cem\u003eL\u003c/em\u003e\u003csub\u003eC\u003c/sub\u003e is the length of the dam axis, and \u003cem\u003eW\u003c/em\u003e is the bottom width of the enlarged foot of the core. The height of most dams is between 40 and 130 m, and the total dam height ranges from 45 to 173 m. The length of the axis of the dam is relatively discrete, which is closely related to the form of the valley. The overall aspect ratio is about 1\u0026thinsp;~\u0026thinsp;8.5. In comparison, the thickness of the core is relatively stable, which basically belongs to the range of 0.6\u0026thinsp;~\u0026thinsp;1.2 m, and the angle of the core slope can reach 71\u0026deg;. In addition, for the contact surface between the core and the plinth, there are both arc contact and flat contact. In order to facilitate the construction, flat joints are widely used in engineering. In response to the research in this paper, the statistics provide valuable information to understand the valley shape conditions, as well as the structural form of the core.\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\u003eBasic information of 20 ACCRDs.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\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=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDam\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCountry\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eYear\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCore type\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eH\u003c/em\u003e\u003csub\u003eC\u003c/sub\u003e/m\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003eH\u003c/em\u003e\u003csub\u003eD\u003c/sub\u003e/m\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cem\u003eL\u003c/em\u003e\u003csub\u003eC\u003c/sub\u003e/m\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cem\u003eT\u003c/em\u003e/m\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003cem\u003eW\u003c/em\u003e/m\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSlope gradient\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c12\"\u003e \u003cp\u003eJoint type\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\u003eFinstertal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAustria\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1977\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eInclined core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e150\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e652\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.5\u0026thinsp;~\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\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\u003eMaopingxi\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1993\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e105\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e889\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.5\u0026thinsp;~\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.48\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eArc contact\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\u003eDong tang\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1996\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e145\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:0.75\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eArc contact\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\u003eStorglomvatn\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNorway\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1997\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e117\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e125\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e825\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.5\u0026thinsp;~\u0026thinsp;0.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.73\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGuanmao zhou\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1999\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e107\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e109\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e242.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.6\u0026thinsp;~\u0026thinsp;1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.19\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eYele\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e120\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e124.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e411\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.6\u0026thinsp;~\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.48\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eShimen\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e94.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e106\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e312.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.6\u0026thinsp;~\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.07\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGuanying dong\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e57.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e241\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.5\u0026thinsp;~\u0026thinsp;1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.75\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eArc contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eErtang gou\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2007\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e64.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.5\u0026thinsp;~\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.11\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBa di\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2009\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e371\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.8\u0026thinsp;~\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:0.78\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKushitayi\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2009\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e90.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e91.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e439\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.4\u0026thinsp;~\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:0.65\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHuangjing ping\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2011\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e75.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e85.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e407.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.6\u0026thinsp;~\u0026thinsp;1.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:0.58\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eQuxue\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2014\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e132\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e173.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e219.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.6\u0026thinsp;~\u0026thinsp;1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:0.33\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eArc contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eJingfo shan\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2014\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e104.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e104.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e320.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.5\u0026thinsp;~\u0026thinsp;1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.07\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHongyu dong\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2015\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e102.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e219.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.8\u0026thinsp;~\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:0.58\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDashi men\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2016\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e128.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e130\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e205\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.6\u0026thinsp;~\u0026thinsp;1.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:0.49\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eZongge lu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAfrica\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2018\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e130\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.6\u0026thinsp;~\u0026thinsp;1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDongtai zi\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2019\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e42.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e45.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1505.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eArc contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTuo pa\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2019\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e59.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e61.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e431.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.5\u0026thinsp;~\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:2.05\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eJiangjia Kou\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2021\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e381\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.6\u0026thinsp;~\u0026thinsp;1.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.80H\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePa zi\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2022\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertical core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e106\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e107.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e108\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.6\u0026thinsp;~\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1\u003cem\u003eV\u003c/em\u003e:1.66\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eFlat contact\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=\"Section2\"\u003e \u003ch2\u003e3.2 Calculation scheme\u003c/h2\u003e \u003cp\u003eFigure\u0026nbsp;3 shows the four sets of computational schemes designed for this study. For the provisions of the slope ratio of the core, China's water conservancy design code\u003csup\u003e[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/sup\u003e requires the slope of the ACC to be lower than 1:0.35. Observing the existing dam structure data, this study combines the joint forms (arc joint, flat joint) of the core to adjust the slope of the bank slope to a relatively extreme situation, that is, the slope of the bank slope is 1\u003cem\u003eV\u003c/em\u003e:0.35\u003cem\u003eH\u003c/em\u003e (71\u0026deg;), 1\u003cem\u003eV\u003c/em\u003e:0.25\u003cem\u003eH\u003c/em\u003e (76\u0026deg;), 1\u003cem\u003eV\u003c/em\u003e:0.15\u003cem\u003eH\u003c/em\u003e (81\u0026deg;). The designed scheme fully considers the high-steep conditions of the valley, and on this basis, the asymmetric valley and the symmetric valley are designed as the control group. In addition, the calculation scheme also considers the embedding depth \u003cem\u003eD\u003c/em\u003e at the joint, which is 0.1 m, 0.3 m and 0.5 m respectively. And the joint amplification angle \u003cem\u003eθ\u003c/em\u003e, 60\u0026deg;, 70\u0026deg;, 80\u0026deg; respectively. In order to understand the influence of joint structure on the mechanical properties of core.\u003c/p\u003e"},{"header":"4 Numerical Computation Model","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e4.1 Finite element model\u003c/h2\u003e \u003cp\u003eThree-dimensional finite element analysis was carried out using ABAQUS software. The finite element mesh of the dam and the mesh of the core joint are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e4\u003c/span\u003e. There are 51816 units and 59083 nodes in the whole ACCRD. The model is meshed by hexahedral elements, and the joints of the core are properly encrypted. The origin of the calculation coordinate system is located at the intersection of the maximum dam section and the base. The origin of the calculation coordinate system is located at the intersection of the maximum dam section and the base. The river direction is the \u003cem\u003eY\u003c/em\u003e axis, the cross river direction is the \u003cem\u003eX\u003c/em\u003e axis, and the vertical direction is the \u003cem\u003eZ\u003c/em\u003e axis. The calculation range of foundation is as follows: it extends 172 m upward and downstream along the flow direction, 172 m along the left and right banks along the dam axis direction, and 172 m along the depth direction. In order to reasonably reflect the mechanical properties of the core, four layers of elements are divided along the thickness direction of the core. The bottom of the model is fully constrained and the surrounding normal constraints.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e5\u003c/span\u003e is the schematic diagram of the maximum dam section. ACC and rockfill body are filled in the same layer, and gravity load is applied step by step. Combined with the actual water storage process as shown in Fig.\u0026nbsp;6, considering the permeability of the upstream dam shell material, it is decided to simulate the hydrostatic pressure by vertically acting on the surface of the asphalt core through the 12-level water storage.\u003c/p\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e4.2 Constitutive model and model parameters\u003c/h2\u003e \u003cp\u003eIn this paper, Duncan Chang E-B material constitutive model is used for rockfill, transition material and ACC. A large number of studies have shown that the stress-strain relationship of asphalt concrete core materials shows obvious nonlinearity\u003csup\u003e[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e. Duncan Chang E-B model considers the hyperbolic dependence of loading/unloading stress path and elastic modulus on the current stress state, which can well describe the nonlinear behavior of asphalt concrete. At present, Duncan Chang E-B model is widely applied to the numerical simulation of asphalt core dam has accumulated a lot of application experience\u003csup\u003e[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e. The material parameters are obtained from the triaxial experiment, and the material parameters are shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\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\u003eDuncan Chang E-B Model Material Parameters.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"10\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaterial\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eρ\u003c/em\u003e (kg/m\u003csup\u003e3\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eK\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003en\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eR\u003c/em\u003e\u003csub\u003e\u003cem\u003ef\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003ec\u003c/em\u003e (MPa)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003eφ\u003c/em\u003e (\u0026deg;)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eb\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cem\u003em\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eur\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRockfill material of Ⅰ\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e900\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e47.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e430\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e1800\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRockfill material of Ⅱ\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2330\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e51.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e580\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e2000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAsphalt concrete core\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2447\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e287\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e31.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e1190\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTransition layer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2320\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1122\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e52.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e567\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e1800\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"10\"\u003eNote \u003cem\u003eK\u003c/em\u003e, modulus of the elasticity coefficient; \u003cem\u003en\u003c/em\u003e, elastic modulus exponent; \u003cem\u003eR\u003c/em\u003e\u003csub\u003e\u003cem\u003ef\u003c/em\u003e\u003c/sub\u003e, failure ratio; \u003cem\u003ec\u003c/em\u003e, cohesion intercept; \u003cem\u003eφ\u003c/em\u003e, friction angle; \u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eb\u003c/em\u003e\u003c/sub\u003e, the bulk modulus coefficient; \u003cem\u003em\u003c/em\u003e, bulk modulus index; \u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eur\u003c/em\u003e\u003c/sub\u003e, Unloading-reloading elastic modulus base.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAccording to the data collected in reference\u003csup\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/sup\u003e, a total of 12 batches of core samples were drilled in the whole construction process of ACC, and the static triaxial experiment was carried out. The test temperature is 15\u0026deg;C, the axial deformation rate is 0.2 mm/min, and the confining pressure is 300, 600, 900, 1200 kPa. Figure\u0026nbsp;7 shows the static triaxial experiment results of one batch of core samples. The strain softening phenomenon occurs under low confining pressure, and the phenomenon is not obvious when the confining pressure is high. The volumetric strain-axial strain curve shows shear contraction at the beginning, followed by dilatancy; the larger the confining pressure is, the more obvious the shear shrinkage phenomenon is, and the shear dilatancy is obviously weakened. The peak strength increases with the increase of confining pressure. It can be seen from the diagram that the axial compressive strain of ACC sample is 10%~27% when it is destroyed.\u003c/p\u003e \u003cp\u003eThe linear elastic model is used to simulate the stress-strain relationship of plinth and bedrock. The calculation parameters are shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\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\u003eLinear Elasticity Material Parameters.\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=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaterial\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eρ\u003c/em\u003e (kg/m\u003csup\u003e3\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eE\u003c/em\u003e (MPa)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eν\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConcrete base\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2400.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e30000.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.167\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBedrock\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2100.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3300.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.250\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eNote: \u003cem\u003eρ\u003c/em\u003e, density; \u003cem\u003eE\u003c/em\u003e, Elastic moduli; \u003cem\u003eν\u003c/em\u003e, Poisson\u0026rsquo;s ratio.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eThe Goodman contact element is used to simulate the stress and deformation of the contact surface between the transition layer and the ACC. The contact parameters are shown in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, and the constitutive relationship of the contact surface is as follows\u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e:\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003cdiv id=\"Equ4\" class=\"Equation\"\u003e \u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ4\" name=\"EquationSource\"\u003e\n$$\\left\\{ {\\begin{array}{*{20}{c}} {\\Delta {\\tau _1}} \\\\ {\\Delta {\\tau _2}} \\end{array}} \\right\\}{\\text{=}}\\left[ {\\begin{array}{*{20}{c}} {{k_{s1}}}\u0026amp;0 \\\\ 0\u0026amp;{{k_{s2}}} \\end{array}} \\right]\\left\\{ {\\begin{array}{*{20}{c}} {\\Delta {\\gamma _1}} \\\\ {\\Delta {\\gamma _2}} \\end{array}} \\right\\}$$\u003c/div\u003e \u003cdiv class=\"EquationNumber\"\u003e4\u003c/div\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eWhere \u003cem\u003ek\u003c/em\u003e\u003csub\u003es1\u003c/sub\u003e and \u003cem\u003ek\u003c/em\u003e\u003csub\u003es2\u003c/sub\u003e are the tangential contact stiffness expressions as:\u003cdiv id=\"Equ5\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ5\" name=\"EquationSource\"\u003e\n$${k_{s1}}{\\text{=}}{\\left( {1 - {R_f}\\frac{{{\\tau _1}}}{{{\\sigma _n}\\tan \\delta }}} \\right)^2}{K_1}{\\gamma _w}{\\left( {\\frac{{{\\sigma _n}}}{{{p_a}}}} \\right)^n}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e5\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Equ6\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ6\" name=\"EquationSource\"\u003e\n$${k_{s2}}{\\text{=}}{\\left( {1 - {R_f}\\frac{{{\\tau _2}}}{{{\\sigma _n}\\tan \\delta }}} \\right)^2}{K_2}{\\gamma _w}{\\left( {\\frac{{{\\sigma _n}}}{{{p_a}}}} \\right)^n}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e6\u003c/div\u003e\u003c/div\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\u003eCalculation parameters of Goodman interface model.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eContact surface\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eR\u003c/em\u003e\u003csub\u003e\u003cem\u003ef\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eK\u003c/em\u003e\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eK\u003c/em\u003e\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003en\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eδ\u003c/em\u003e(\u0026deg;)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003ec\u003c/em\u003e(kPa)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBetween the core\u003c/p\u003e \u003cp\u003eAnd transition layer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2600.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5000.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e30.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e23.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBetween the core and\u003c/p\u003e \u003cp\u003econcrete cushion block\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6000.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e20000.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e20.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e100.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBetween rockfill materials\u003c/p\u003e \u003cp\u003eand concrete cushion block\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2800.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5500.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e100.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eNote: \u003cem\u003eK\u003c/em\u003e\u003csub\u003e1\u003c/sub\u003e, \u003cem\u003eK\u003c/em\u003e\u003csub\u003e2\u003c/sub\u003e, \u003cem\u003en\u003c/em\u003e, \u003cem\u003eR\u003c/em\u003e\u003csub\u003e\u003cem\u003ef\u003c/em\u003e\u003c/sub\u003e, nonlinear contact parameters, determined by experiment; \u003cem\u003eδ\u003c/em\u003e, contact surface friction angle. \u003cem\u003eγ\u003c/em\u003e\u003csub\u003ew\u003c/sub\u003e, water density; \u003cem\u003eP\u003c/em\u003e, atmospheric pressure.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e4.3 Comparison of measured data and computed results\u003c/h2\u003e \u003cp\u003eIn order to better verify the calculation model of this study, combined with the measured data from the strain and deformation to prove the rationality of the numerical model. The monitoring information is the local vertical strain measured in the core after reservoir impoundment in November 2017, and combined with the monitoring data\u003csup\u003e[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/sup\u003e, it can be found that the trend of the strain between the computed results and the measured results is close as shown in Fig.\u0026nbsp;8(a). According to the measured data, the vertical strain of the upstream surface of the core is compressive strain and less than about 4.0%. The overall trend shows that the higher the elevation, the smaller the compressive deformation. The finite element calculation shows that the whole section of the core is compressed, the large compressive strain is mainly concentrated on the side near the gentle bank slope, and the vertical compressive strain is about 2% at the bottom. The computed maximum value is slightly smaller than the monitoring value, but the calculated values of other elevations are very close to the measured values. The monitored and calculated values are less than the compressive strain obtained from the triaxial experiment (Fig.\u0026nbsp;7).\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;8(b) compares the calculated and measured lateral displacement of the core A section at four different water levels. According to the actual water storage process\u003csup\u003e[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]\u003c/sup\u003e, the water storage began from el.2208 m on February 12, 2017. On March 15, the water level reached el.2280 m and rose by 72 m in 31 days. On April 13, it reached el.2310 m, up 30 m from the previous stage. The subsequent water level rose slowly, reaching el.2320 m on June 7 and rising to el.2327 m on November 19. The whole water storage process lasted for 9 months. In order to ensure the calculation accuracy, this water storage process is well reflected by the analysis step of the software. Combined with the actual measurement results, it can be found that the trend of the core's lateral displacement along the elevation shows an increase and then decrease. With the increase of water level, the displacement along the river increases obviously. The finite element simulation results show the same variation curve as the measurement results. However, the numerical simulation results are larger than the measurement results by 2\u0026thinsp;~\u0026thinsp;3 cm, which is within a reasonable range and confirms the accuracy of the simulation results.\u003c/p\u003e\u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e9\u003c/span\u003e shows the layout of the engineered water level meter, and compares the measured and detected dam deformation. Five settlement points are arranged in the cross section B at el.2244 m, and the vertical settlement of the dam is measured by water level gauge(\u003cem\u003eWLG\u003c/em\u003e). The settlement distribution and size of the el.2244 m measuring point are recorded when the dam rises from el.2289 m to el.2334.2 m. The computed deformation mode is roughly the same as the monitoring data. In summary, the calculation model in this paper can accurately reflect the mechanical properties of ACCRD.\u003c/p\u003e\u003c/div\u003e"},{"header":"5 Results and Discussion","content":"\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e5.1 Influence of narrow valley on the stress of ACC\u003c/h2\u003e \u003cp\u003eUnder the condition of high-steep bank slope, the shear effect and arching effect of core can\u0026rsquo;t be ignored. Figure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e10\u003c/span\u003e shows the distribution of stress level. It can be found that the distribution of stress level in the completion period and the impoundment period is very similar. The stress level in the impoundment period is slightly higher than that in the completion period, and the dam body has two areas with high stress level. One appears near the upstream contact surface between the dam body and the core, with a large range and a high stress level. There are two reasons for the high stress level in this area. First, the modulus difference between the core and the dam rockfill is large, resulting in large uneven settlement in the area, resulting in large shear deformation. Second, under the action of water pressure, the deformation of the core to the downstream causes the small principal stress \u003cem\u003eσ\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e in this area to decrease greatly, which makes the stress level increase\u003csup\u003e[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/sup\u003e. However, the direction of shear deformation points to the inside of the dam body, which will not affect the stability of the upstream dam shell. Another area with high stress level in the dam is the contact part between the dam and the bank slope. It can be found that the stress level at the steeper position of the bank slope is relatively high, and the maximum dislocation displacement is 3.62 cm. This is due to the steep slope, the dam and the core will produce large shear deformation along the slope direction. At the same time, under the action of water pressure, the core will also undergo shear deformation downstream. Therefore, it is necessary to pay attention to the shear stress level of the core during the impoundment period.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;11 shows the contour distribution of tensile stress and shear strain of the core. Combined with Fig.\u0026nbsp;11(a), it can be found that from completion to impoundment, the tensile stress of the core increases, and the maximum tensile stress reaches 0.54 MPa, which is located at the end of the left bank of the core. In this process, the tensile area of the core is always concentrated at the top. However, it is worth noting that the tensile area and tensile stress on the right bank are significantly smaller than those on the left bank. This is because the right bank slope shows a trend of slowing down from the top to the bottom, which makes the tensile stress concentrate in a steeper section. Combined with the shear strain in the \u003cem\u003eXZ\u003c/em\u003e direction in Fig.\u0026nbsp;11(b), it is further understood that the shear strain in the impoundment period is also larger than that in the completion period. At the same time, it can be found that the length of the potential slip zone on the right bank is longer than that on the left bank, where the compressive strain is on the slow side (the right bank side); the tensile strain is located on the steep side (the left bank side), and the maximum value is 1.69%, which is located at about 1/5 dam height of the left bank slope. This is because the steeper the bank slope, the greater the component force along the slope.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;12 shows the stress reduction of the core during the completion period and the impoundment period. Combined with Fig.\u0026nbsp;12(a), it can be found that the distribution of the arching coefficient \u003cem\u003eR\u003c/em\u003e in the completion period and the impoundment period is not much different, and there is obvious aggregation near the slope on both sides. For such 'V' type valleys, under the condition of high-steep bank slopes, the arching coefficient \u003cem\u003eR\u003c/em\u003e near the upper bank slope of the core is significantly reduced, indicating that the stress transfer between the core and the surrounding soil is obvious, resulting in a strong arching. But the difference is that the arching in the completion period is obviously weaker than that in the impoundment period. This is mainly due to a certain degree of increase in the vertical stress of the core under water presssure, and the results are similar to those in the reference\u003csup\u003e[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]\u003c/sup\u003e. It can be found from Fig.\u0026nbsp;11b that compared with the completion period, the change of stress caused by the impoundment period is dominant, and the strain has no significant change. In addition, after impoundment, the arching coefficient \u003cem\u003eR\u003c/em\u003e does not change much with the reservoir water level, and most of them are within 10%, indicating that the arching during the construction period plays a decisive role in the arching after impoundment. Therefore, more attention should be paid to the arching during the completion period\u003csup\u003e[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003e5.2 Influence of joint form under asymmetric valley condition\u003c/h2\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e13\u003c/span\u003e shows the variation law of arc joint and flat joint core stress level under different bank slope gradients. The research object comprehensively considers the actual terrain conditions (V-shaped valley, steep bank slope, asymmetry). Here, the dam height and the size of the bottom base are kept unchanged, and the slope of the steep bank slope on the left bank is adjusted, which can be analogized to widening the length of the dam axis. The calculation results show that as the slope of the left bank becomes steeper, the stress level and shear stress \u003cem\u003eS\u003c/em\u003e13 component of the core decrease. The maximum stress level is located in the left bank near the bottom area, and there is also a large area of high stress level in the middle of the right bank, which is consistent with the conclusion of the reference\u003csup\u003e[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]\u003c/sup\u003e. The rock on the left bank is steep and the core has a large misalignment along the bank slope. As the bank slope slows, the component force of gravity on the soil above the unit length becomes larger, resulting in an increase in shear stress \u003cem\u003eS\u003c/em\u003e13 downslope. In order to compare the differences in stress level contour distributions between the two joint forms more intuitively, the areas with \u003cem\u003eS\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.24 are shaded according to the calculation results. It is worth noting that the stress level of the whole joint of the arc joint is higher than that of the flat joint, and the overall stress level of the arc joint core is also higher than that of the flat joint core. This is because the arc joint is embedded inside the plinth, and under the action of water load, the embedded part restricts the deformation of the core. In the asymmetric V-shaped steep valley, the stress of the arc contact surface is not uniform, and the local extrusion deformation is large. The uncoordinated deformation leads to a large stress mutation in the convex part of the arc contact surface, especially in the middle of the contact surface.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e14\u003c/span\u003e shows the variation law of arc joint and flat joint core arching with different bank gradients. It was pointed out that when the vertical stress in the core is 20%-50% of the vertical stress in the adjacent soil material at the same elevation, cracks may occur in the core. In order to analyze the law of stress transfer more intuitively, take 0.2 as the limit of the arching coefficient \u003cem\u003eR\u003c/em\u003e, and find the percentage of the area of the whole core area when the arching coefficient \u003cem\u003eR\u003c/em\u003e is lower than 0.2\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e. The results show that in the asymmetric V-shaped valley, as the bank slope slows down, the area percentage corresponding to \u003cem\u003eR\u003c/em\u003e less than 0.2 and the shear strain increase, and the stress transfer of the core increases. The arching on the left bank slope and the top of the right bank slope is the strongest. The largest arching area accounts for 8.64%, and the corresponding maximum \u003cem\u003eE\u003c/em\u003e\u003csub\u003e\u003cem\u003eXZ\u003c/em\u003e\u003c/sub\u003e is 1.4%. Taking the left bank side as an example, the arching coefficient \u003cem\u003eR\u003c/em\u003e decreases and then increases along the left bank slope. It is worth noting that the arching of the arc joint core is higher than that of the flat joint. Although the overall arching distribution position of the two is similar, the low stress area of the arc joint extends to the top of the core. The reason is that the high stress level area of the arc joint core extends along the slope to the top of the core.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003e5.3 Influence of joint form under symmetric valley condition\u003c/h2\u003e \u003cp\u003eFigure\u0026nbsp;15 is the stress level variation law of the arc joint and the flat joint core under different bank slope gradients in the symmetrical valley. Combined with Fig.\u0026nbsp;15(a), it can be found that the stress level of the core is a process of 'increase-decrease-increase-decrease' along the elevation. Compared with the asymmetric valley, the maximum stress level in the symmetric valley is located at the bottom of the core, and the maximum stress level in the asymmetric valley is located on the side of the steep bank slope near the bottom. This is because the stress level in this paper reflects the overall shear characteristics of the core. The vertical extrusion at the bottom of the symmetrical valley core and the thrust along the river are the largest, and there is a large deformation. Of course, the stress level \u003cem\u003eS\u003c/em\u003e near the bottom of the core axis is relatively large about 0.3. This is attributed to the distribution characteristics of the principal stress \u003cem\u003eσ\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e of the core. The sharp decrease of the minor principal stress \u003cem\u003eσ\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e at the bottom of the core will lead to a significant increase in the stress level. In other words, the symmetry of the valley will lead to stress deflection and affect the shear stress \u003cem\u003eS\u003c/em\u003e13 characteristics of the core. The symmetrical valley can evenly distribute its own gravity along the slope direction. On the whole, the maximum stress level \u003cem\u003eS\u003c/em\u003e and shear stress \u003cem\u003eS\u003c/em\u003e13 of the core are increasing with the bank slope steepening. The maximum stress level \u003cem\u003eS\u003c/em\u003e and shear stress \u003cem\u003eS\u003c/em\u003e13 of the arc joint core are greater than those of the flat joint core, and the maximum stress level \u003cem\u003eS\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.47 and shear stress \u003cem\u003eS\u003c/em\u003e13\u0026thinsp;=\u0026thinsp;554.8 kPa, as shown in Fig.\u0026nbsp;15(b). The above results show that the shear characteristics of arc joint core are more sensitive to the change of bank slope. For the symmetrical valley, the shear effect of the flat joint core is weak, and the adaptability to the steep bank slope will be better.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;16 shows the variation law of arc joint and flat joint core arching under different bank slope gradients in symmetrical valley. The calculation results show that the arching coefficient \u003cem\u003eR\u003c/em\u003e at the central axis of the core is 'decrease-increase-decrease-increase' along the elevation. The arching in the middle and upper part of the core is strong, and its change trend is opposite to the change trend of the stress level \u003cem\u003eS\u003c/em\u003e along the elevation. It shows that the shear effect is enhanced, the arching of the core is enhanced, and the two are closely related. Combined with the contour map Fig.\u0026nbsp;16(a), it can be found that the area with arching coefficient \u003cem\u003eR\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.2 is located on the slope side of both banks and extends to the top of the dam, which is symmetrically distributed. According to the shear stress contour map in Fig.\u0026nbsp;15(b), it is well verified that the shear stress on the slope side of the core is obviously stronger than that in other areas. This shear stress will prevent the settlement of the core, so that part of the vertical deformation of the core will be transferred to the harder bedrock, resulting in tensile areas on both sides and at the top of the core. The maximum tensile stress is 443.7 kPa, which is located at the top of the core, as shown in Fig.\u0026nbsp;16(b). On the whole, the bank slope becomes steeper, the percentage of the area where the arching coefficient is less than 0.2 increases, and the arching of the core is increasing. The area proportion of the arc joint core \u003cem\u003eR\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.2 corresponding to the slope of 1:0.15, 1:0.25, 1:0.35 is 7.4%, 6.49% and 5.58% respectively. The flat joint core is 7.03%, 6.04% and 5.09% respectively. Similarly, the arching and tensile stress of the arc joint core are higher than those of the flat joint core. The above results show that the shear action of the core will cause the stress redistribution of the core, and for the symmetrical valley, the arching of the flat joint core under the condition of steep bank slope is relatively low.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003e5.4 Influence of joint embedment depth\u003c/h2\u003e \u003cp\u003eFigure\u0026nbsp;17 shows the overall distribution law of core stress level under different embedded depths of joints. The calculation results show that the core maximum stress level \u003cem\u003eS\u003c/em\u003e and the core maximum shear stress \u003cem\u003eS\u003c/em\u003e13 increase with the increase of the the core joint embedded depth \u003cem\u003eD\u003c/em\u003e. The maximum stress level \u003cem\u003eS\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.35 and the shear stress \u003cem\u003eS\u003c/em\u003e13\u0026thinsp;=\u0026thinsp;452.3 kPa are higher than the flat joint core. In addition, the maximum value of shear stress \u003cem\u003eS\u003c/em\u003e13 occurs at the shoulder of the core, as shown in Fig.\u0026nbsp;17(a). Due to the symmetrical distribution of stress level contours, the right bank side of the core is taken for analysis. It is worth noting that the stress level is higher in three regions, namely: the bottom of the core, the slope of the core near the bottom, and the middle and upper part of the core, in which the maximum value of the stress level occurs at the bottom of the core, as shown in Fig.\u0026nbsp;17(b). This is the same as the calculation results of reference\u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e. The shear dislocation deformation at the shoulder of the core is the largest, reaching 37.8 mm, and the bottom of the core reaches 2mm. For the stress level \u003cem\u003eS\u003c/em\u003e at the characteristic position (excluding the high stress level area at the shoulder and the bottom of the core), the shear effect is the strongest, at about 1/3\u003cem\u003eH\u003c/em\u003e from the bottom.\u003c/p\u003e\u003cp\u003eCombined with the distribution of the stress level of the core in different directions, the above rules (as shown in Fig.\u0026nbsp;18) are further elaborated. The measuring line transits from the central axis A-A of the core to the C-C of the bank slope, as shown in Fig.\u0026nbsp;18(a). The stress level \u003cem\u003eS\u003c/em\u003e at the bottom and top of the measuring line are significantly different. The stress level \u003cem\u003eS\u003c/em\u003e in the upper and middle parts of the core and most of the bottom areas are high. On the C-C side of the core bank slope, with the increase of the embedding depth \u003cem\u003eD\u003c/em\u003e, the stress level \u003cem\u003eS\u003c/em\u003e in the middle and lower part of the core increases. This may be because the embedded depth increases under the action of water load, and the constraint effect of the core wall becomes larger. Figure\u0026nbsp;18(b) shows the distribution of the core stress level along the longitudinal direction. It can be found that the stress level on both sides of the bank slope is first higher than the middle region and gradually decreases to lower than the middle region as the height increases. Compared to other areas of the core, the core joints are the most sensitive to stress changes. This is due to the fact that the contact surface is made up of two materials with huge differences in stiffness, and there will be significant shear action at such interfaces of soft and hard contact. For the core as a whole, the increase of embedding depth will enhance the local shear effect of the core.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;19 shows the distribution law of core arching coefficient in different directions under different embedded depths of joints. It can be found that with the change of joint type, the difference of core stress behavior is mainly concentrated on the bank slope side. Combined with Fig.\u0026nbsp;19(a), taking the core right bank slope as an example, as the embedding depth of the core increases, the arching coefficient in the middle and lower parts of the core decreases, indicates that the arching of the core increases, which corresponds to the distribution law of the core stress level. Overall, the percentage of the area where the core arching coefficient \u003cem\u003eR\u003c/em\u003e is less than 0.2 does not change much. The values corresponding to \u003cem\u003eD\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.1, 0.3 and 0.5 m are 5.1%, 5.12% and 5.2%, respectively. When the core\u0026rsquo;s shape structure does not change much, it is more likely to affect the local stress state of the core. As shown in Fig.\u0026nbsp;19(b), it can be concluded from analyzing the stress transfer in the core at the same elevation that the stress transfer on the bank slope side of the core is significantly higher than that in the middle of the core, and the arching coefficient decreases dramatically near the bank slope.\u003c/p\u003e\u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003e5.5 Influence of joint amplification angle\u003c/h2\u003e \u003cp\u003eFigure\u0026nbsp;20 shows the stress level and shear stress distribution of the core under different joint magnification angles. The maximum stress level \u003cem\u003eS\u003c/em\u003e corresponding to \u003cem\u003eθ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;60 \u0026deg;, \u003cem\u003eθ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;70 \u0026deg; and \u003cem\u003eθ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;80 \u0026deg; are 0.33, 0.35 and 0.40, respectively. The shear stress \u003cem\u003eS\u003c/em\u003e13 increases from 290.5 kPa to 349.3 kPa, which is within the allowable shear strength range. With the increase of the angle, the maximum value of the overall stress level and the maximum shear stress of the core are increasing. Based on the stress level contour map, it can be found that the stress level at the bottom, middle and upper parts of the core and the slope side of the core are higher, as shown in Fig.\u0026nbsp;20(a). The distribution law of stress level along the right bank slope of the core can well explain the above phenomenon. In general, the distribution law of stress level along the elevation is consistent. The stress level at the top of the arc joint core is the largest. With the increase of the joint amplification angle, the stress level on the side of the bank slope is also increasing. The distribution law of stress level \u003cem\u003eS\u003c/em\u003e along the right bank slope of the core can well explain the above phenomenon. In general, the distribution law of stress level \u003cem\u003eS\u003c/em\u003e along the elevation is consistent. The stress level \u003cem\u003eS\u003c/em\u003e at the top of the arc joint core is the largest. With the increase of the joint amplification angle, the stress level \u003cem\u003eS\u003c/em\u003e on the side of the bank slope is also increasing, as shown in Fig.\u0026nbsp;20(b). In order to better explain the shear mechanism of the joint, flat joints with different magnification angles were further set up. The results show that there is a significant difference in the distribution of the stress level along the elevation of the right bank slope of the arc joint and the flat joint core, which is mainly reflected in the middle and lower regions and the top of the core. Taking 80 m elevation as the boundary, the stress level of the flat joint increases first and reaches the first peak near 30 m. The stress level of the middle and lower part of the right bank slope of the flat joint core is higher than that of the arc joint core. For flat joints, expanding the contact surface can reduce the stress level. The angle decreases and the contact surface expands, which can reduce the stress level.\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;21 is the distribution law of core arching coefficient under different joint magnification angles. The effect of the joint magnification angle change on the overall arching of the core was not significant (as shown in Fig.\u0026nbsp;21(a)), and the percentage of area corresponding to arching coefficient \u003cem\u003eR\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.2 stabilized at 5.12%, which was concentrated near the core slope. As shown in Fig.\u0026nbsp;21(b), the arching coefficient \u003cem\u003eR\u003c/em\u003e at the bank slope of the core gradually decreases from the bottom to the top, and the arching coefficient \u003cem\u003eR\u003c/em\u003e at the bank slope is less than 0.5. It is worth noting that compared with the arc joint, the arching coefficient \u003cem\u003eR\u003c/em\u003e on the bank slope side of the flat joint core varies greatly. It can be seen that the smaller the angle, the lower the arching coefficient \u003cem\u003eR\u003c/em\u003e of the slope side of the core.\u003c/p\u003e "},{"header":"6 Conclusion","content":"\u003cp\u003eBased on numerical analysis, this study first analyzes the adaptability of arc joints and flat joints to different types of steep slope valleys (asymmetric valleys and symmetric valleys). On this basis, the shear law of ACC is deeply analyzed in terms of the core embedment depth and the core amplification angle. The main conclusions are as follows:\u003c/p\u003e \u003cp\u003e(1) Under the condition of high and steep bank slope, there is a large shear deformation of ACC. The stress level near the steep bank slope is high, which produces a significant arching, and the arching coefficient is less than 0.5. The tensile stress zone is concentrated on the shoulders of the core, and the maximum tensile stress reaches 0.54 MPa.\u003c/p\u003e \u003cp\u003e(2) For the asymmetric V-shaped valley, adjusting the slope of the steep bank slope on one side, the bank slope becomes steeper, the length of the dam axis is shortened, the overall stress level of the core and the arching are reduced, and the structure of the multi-section slow bank slope can well alleviate the shear effect; compared with the flat joint, the stress level of the arc joint of the core is concentrated, and the arching is strong.\u003c/p\u003e \u003cp\u003e(3) The symmetry of the valley will lead to the deflection of the stress and affect the shear stress characteristics of the core. Under the condition of symmetrical valley, the maximum stress level is located at the bottom of the core, and the shear effect and arching of the core with steep slope are enhanced. The shear characteristics of the arch joint core are highly sensitive to the change of slope gradient, and the overall stress level and arching of the arch joint core are higher than those of the flat joint.\u003c/p\u003e \u003cp\u003e(4) Increasing the embedding depth of the joint will enhance the local shear effect of the core. The stress level of the core ranges from 0.3 to 0.4. When D\u0026thinsp;=\u0026thinsp;0.5 m, the core \u003cem\u003eS\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e = 0.35, and the maximum shear stress is 452.3 kPa, which appears at the shoulder of the core.\u003c/p\u003e \u003cp\u003e(5) As the angle of the core joint decreases, the maximum stress level of the core and the maximum shear stress decrease by 17%. The stress levels corresponding to \u003cem\u003eθ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;80\u0026deg;, \u003cem\u003eθ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;70\u0026deg;, and \u003cem\u003eθ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;60\u0026deg; are 0.20, 0.16 and 0.14, respectively. Expanding the contact surface of the joint can reduce the stress level.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eYong Li: Conceptualization, Methodology, Validation, Writing-review \u0026amp; editing.Yanlong Li: Formal analysis, Supervision, Funding acquisition.Yunhe Liu: Funding acquisition.Xinjian Sun: Investigation and Validation.Lifeng Wen: Formal analysis.Weimei Li: Acquisition of data.\u003c/p\u003e\u003ch2\u003eAcknowledgments\u003c/h2\u003e \u003cp\u003eThe work was supported by the National Natural Science Foundation of China (Grant No. 52039008); the China National Funds for Distinguished Young scientists (Grant No. 52125904); the National key R\u0026amp;D plan (Grant No. 2022YFC3004403); the Program 2022TD-01 for Shaanxi Provincial Innovative Research Team (No. 2022TD-01).\u003c/p\u003e\u003ch2\u003eData Availability Statement\u003c/h2\u003e \u003cp\u003eThe date used to support the findings of this study are available from the corresponding author upon request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLi YL, Tang W, Wen LF, Wu HB (2020) Dam seismic deformation evaluation method of asphalt concrete core rockfill dam and its reliability analysis[J]. 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Comput Geotech 128:103814\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBeiranvand B, Komasi M (2020) Study of the Arching Ratio in Earth Dam by Comparing the Results of Monitoring with Numerical Analysis (Case Study: Marvak Dam) [J]. Iranian Journal of Science and Technology, Transactions of Civil Engineering\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGao J, Dang FN, Ma ZY (2020) Reduction measure research for reduction of high stress level of ultra-high asphalt concrete core[J]. Rock Soil Mech 41(5):1730\u0026ndash;1739\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":"asphalt concrete core, steep bank slope, joint form, stress, shear deformation","lastPublishedDoi":"10.21203/rs.3.rs-3988129/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3988129/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe connection performance between the core and the concrete plinth under steep bank slope conditions is related to the overall seepage safety of the dam. In this study, combined with the actual engineering, the steep slope control groups with slopes of 71\u0026deg;, 76\u0026deg; and 81\u0026deg; were designed. The research scheme not only considers the limit situation of the existing specifications, but also makes further exploration on the situation of high and steep valleys beyond the specifications. Considering the asymmetric valley and the symmetric valley, two contact forms of arc joint and flat joint are set up. Based on the numerical calculation, the influence of the joint embedding depth and the amplification angle on the shear action of the asphalt concrete core (ACC) is quantitatively studied. The results indicate that the symmetry of the valley will cause stress to deflect, affecting the characteristics of shear stress of the core. Under the condition of high-steep bank slope, large shear deformation occurs at the joint of ACC, and significant arching occurs near the bank slope. The overall stress level of the arc joint is higher than that of the flat joint, and it is highly sensitive to the change of the bank slope. Increasing the embedded depth of the joint, the local shear effect of the core wall becomes larger. As the joint magnification angle decreases, the stress level of the core and the maximum shear stress decrease. Expanding the contact surface of the joint can reduce the shear effect of the core. This study breaks through the conventional dam construction conditions and explores the mechanical properties of anti-seepage bodies in high and steep valleys. The research results of this paper can provide reference for the design of ACC joints under extreme steep bank slope conditions.\u003c/p\u003e","manuscriptTitle":"Influence of joint form on shear characteristics of asphalt concrete core under steep bank slope condition","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-06 19:01:30","doi":"10.21203/rs.3.rs-3988129/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":"e760f3dd-d631-4a86-a4e5-2f3218480a23","owner":[],"postedDate":"March 6th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-05-09T08:22:10+00:00","versionOfRecord":[],"versionCreatedAt":"2024-03-06 19:01:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3988129","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3988129","identity":"rs-3988129","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}