岩土工程技术

2026, 40(5): 1-1.

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2026, 40(5): 1-3.

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Theoretical research and new advances in pile foundation engineering: a review of the 16th Pile Foundation Engineering Academic Conference

QIU Rendong, ZHU Zhaojing, GAO Wensheng, REN Xinjian, LIN Li, SUN Wei, MENG Jiahui

2026, 40(5): 633-644. doi: 10.20265/j.cnki.issn.1007-2993.2025-0603

[Abstract](73) [FullText HTML] (33) [PDF 534KB](12)

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This paper provides a comprehensive review of the advances in theoretical research and engineering practice of pile foundation engineering, as presented at the 16th Pile Foundation Engineering Academic Conference. The review encompasses five main aspects: keynote speeches, theoretical and experimental research, pile foundation design research and practice, pile construction techniques and environmental effects, and pile testing technologies. The topics covered under theoretical and experimental research include: pile foundation issues specific to the geological conditions in Guangdong Province; experimental studies on the effects of ground temperature on pile bearing capacity and serviceability; experimental investigations into pile bearing behavior under special conditions; theoretical and experimental studies on the load-bearing performance of composite piles; dynamic and shaking table tests for pile foundations; and experimental studies on the effects of jacking schemes on pile jacking construction parameters. Research and practice in pile foundation design focus on: determining side and end resistances in pile design; applications of pile foundations in ground and foundation reinforcement; pile design in marine under-consolidated soil layers; practical applications of artificial intelligence (AI) in pile design; optimization of pile foundation design schemes; and recent advances in pile design for wind power projects. Topics regarding pile construction techniques and environmental effects involve: environmental impacts of static drilling and root-planting piles; environmental effects of pile installation in special geological strata; pile construction techniques in low-headroom conditions; impacts of shield tunneling on the deformation of existing adjacent piles; applications of AI in pile construction; and discussions on post-grouting techniques for pile foundations. Finally, the pile testing technologies section covers: evaluation of pile integrity testing methods; exploration of novel pile testing technologies; theoretical research in pile testing; and testing techniques for precast piles.

Construction technique and bearing performance of bored pile in karst areas: a review

LIU Zhanlong, LIU Bo, CHU Hui, SU Chao

2026, 40(5): 645-656. doi: 10.20265/j.cnki.issn.1007-2993.2025-0277

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Bored piles have been widely applied in foundation engineering in karst areas due to their advantages of broad applicability, high bearing capacity, and relatively convenient construction. However, the complex geological environment in karst regions—characterized by karst caves, dissolution fractures, and uneven bedrock surfaces—significantly affects the construction quality and bearing performance of bored piles. Based on a systematic review of domestic and international literature and combined with the practical engineering conditions in karst areas, this paper comprehensively analyzes and reviews the geomorphological characteristics of karst landforms, bored pile construction techniques, construction quality control methods, and bearing capacity prediction and evaluation technologies. Furthermore, the future development trends of bored pile engineering in karst areas are discussed, aiming to provide valuable references and insights for pile foundation engineering in similar geological conditions.

Current status and adaptability research of intelligent robots in complex tunnel construction environments

LIU Zhifeng, HE Hongtong, CHEN Chen, WANG Jing, ZHANG Jizhe

2026, 40(5): 657-663. doi: 10.20265/j.cnki.issn.1007-2993.2025-0275

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The tunnel construction environment exhibits extreme complexity and traditional manual and mechanical construction methods have low efficiency and strong subjectivity. With their advanced perception, decision-making, and execution capabilities, intelligent robots have significantly enhanced the precision and reliability of tunnel engineering construction in complex environments. This study systematically analyzes the distinctive characteristics of tunnel construction environments. On the basis of summarizing the current research status at home and abroad, it identifies three predominant factors - complex geological conditions, spatial constraints, and harsh working environments - that significantly impact the operational performance of intelligent robots. Starting from engineering cases, it demonstrates the advantages of intelligent robots in improving tunnel construction efficiency, quality, and safety. At the same time, the technical factors affecting the adaptability of intelligent robots, such as navigation and positioning accuracy, communication stability, energy supply and endurance, as well as engineering factors such as construction process matching and collaborative operation ability with other equipment, were explored. Finally, a series of practical and feasible strategies were proposed, including customized design and strengthening the standardization of collaborative operation between equipment, to ensure that intelligent robots can better adapt to complex tunnel construction environments and process requirements, and improve tunnel construction efficiency and safety.

Settlement characteristic at the junction area of surcharge preloading and semi-rigid composite foundation in soft soil sites

SHEN Minglong, DAI Yiming, CHEN Huahan

2026, 40(5): 664-671. doi: 10.20265/j.cnki.issn.1007-2993.2025-0257

[Abstract](44) [FullText HTML] (19) [PDF 840KB](8)

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To investigate the deformation characteristics of the junction area between surcharge preloading and semi-rigid composite foundation treatments, this paper takes a ground treatment project in a deep soft soil site as an example. A finite element model of the junction area with two different ground treatment types is established to analyze the long-term development trends of surface settlement and differential settlement in the post-construction stage. The results show that: (1) The development rates of both surface settlement and differential settlement in the junction area decrease year by year; (2) The location of the maximum differential settlement continuously shifts from the junction interface towards the composite foundation area over time, ultimately locating at a position 1.9 times the height of the surcharge slope shoulder outside, and is unaffected by the pile spacing; (3) The maximum value of the surface slope rate exhibits a nonlinear relationship with the pile-soil replacement ratio, and when the replacement ratio is lower than 0.13, the control effect on the maximum differential settlement is significant; (4) Using a surface slope rate of 0.5% as the standard, the critical replacement ratio for exceeding the limit is approximately 0.114. When the replacement ratio is lower than this value, the differential settlement in the junction area exceeds the limit. For common replacement ratios of composite foundations, the overlimit range is symmetrically distributed around the position of the maximum value, with a width within 16 meters.

Application of comprehensive geological prediction technology in Wuzhishan Tunnel

WANG Zhou, ZHENG Yuhui, CUI Liang, MAO Chuan, LIU Lei

2026, 40(5): 672-681. doi: 10.20265/j.cnki.issn.1007-2993.2025-0211

[Abstract](50) [FullText HTML] (24) [PDF 6808KB](5)

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During the construction of tunnels under complex geological conditions, to investigate the geological conditions ahead of the tunnel face and prevent adverse geological hazards such as soft rock fracture, water inrush and mud outburst, a management system for dynamic comprehensive geological prediction and design of tunnels should be established with geological analysis as the main line and the combination of long and short distance advanced geological prediction as the basis. In the construction of the Wuzhishan Extra long Tunnel on the Renshou to Pingshan Xinshi section of the G4216 Expressway, aiming at various adverse geological bodies, multiple advanced geological prediction methods including geological analysis, advanced horizontal drilling, ground penetrating radar, transient electromagnetic method and seismic wave method were adopted. A management system for dynamic comprehensive prediction and design was constructed to guide dynamic design, and post excavation comparative verification was carried out according to construction progress. This management system reduces geological safety risks in tunnel construction, featuring scientificity, economy and safety. It can provide references for advanced geological prediction and dynamic design of tunnels under similar complex geological conditions.

In-plane stability analysis of frame-type concrete strut for foundation pit engineering

HU Jisong, ZHOU Shudong

2026, 40(5): 682-692. doi: 10.20265/j.cnki.issn.1007-2993.2025-0198

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The excavation specifications do not specify the calculation length value for the stability of the concrete frame support plane. Currently, the calculation length coefficient formula for frame columns in steel structures, concrete specifications, and related research does not consider the influence of support length and fixed boundary conditions at both ends. Based on the load-bearing model, a systematic in-plane stability analysis of the frame bracing system is conducted by treating the bracing members as mega-lattice columns. Utilizing the exact theoretical solution for the stability buckling of battened lattice columns, and accounting for the individual member action, the effective length of the bracing, and the fixed-end boundary conditions, a formula for the effective length factor of the bracing is derived. Furthermore, the energy method is employed to deduce the in-plane effective length factor formula for bracing members with fixed-end boundary conditions, incorporating the lateral stiffness of the steel columns. The calculated results demonstrate a high degree of agreement with those obtained from finite element eigenvalue buckling analysis, confirming that the proposed formulas achieve sufficient accuracy for practical engineering design applications.

Theoretical study and application of pile foundation bearing capacity of broken bedrock building

YUAN Jianfei, WANG Kunyi, LI Shengqun, ZHANG Jianwei, LI Lianxiang, GUO Rui

2026, 40(5): 693-702. doi: 10.20265/j.cnki.issn.1007-2993.2025-0244

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In order to solve the problem of designing embedded piles in fractured bedrock areas, the bearing capacity calculation methods, calculation parameters and application scope of embedded piles used in two domestic codes are analysed. According to the “Code for Design of Foundation and Subgrade of Highway Bridges and Culvert”, the approach to accounting for the bearing capacity factors of end and side resistance of piles considering rock integrity, the method of calculating the bearing capacity of embedded piles with broken bedrock is modified to obtain a method suitable for broken bedrock building. The Mohr-Coulomb parameter based on the modified Hoek-Brown criterion is used to carry out finite element simulations to obtain the ultimate bearing capacity of monopiles with fractured bedrock embedded piles, and to model pile raft foundations with different degrees of integrity and analyse their bearing capacity and monopile bearing properties. The results show that the modified bearing capacity calculation method is scientific and the fractured bedrock still has good bearing capacity as the bearing layer of group pile foundation. The results are applied to the optimal design of pile foundation for a super high-rise project in the fractured bedrock area of Jinan, and the relevant results can be used as reference for similar projects.

Calculation and verification of ground settlement due to precipitation in a confined aquifer

FU Qiaosong, LIU Pan, DING Chunfu, YAO Aijun, LI Liyun

2026, 40(5): 703-710. doi: 10.20265/j.cnki.issn.1007-2993.2025-0299

[Abstract](63) [FullText HTML] (14) [PDF 1913KB](9)

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In the underground excavation construction of Tiantongyuan Station of Beijing Metro Line 13, due to the rich groundwater and the tunnel floor located in the confined aquifer, the effect of the waterproof curtain is not good and the cost is high. Therefore, the confined aquifer is pre-dewatered and decompressed before excavation to control groundwater. In order to predict the surface subsidence caused by precipitation, this study established a mathematical model of regional division based on the three-dimensional groundwater dynamics theory, which comprehensively considered the distribution curve of precipitation pressure in confined aquifer and the spatial position of aquiclude roof. After dividing the stress area of confined aquifer into non-pressure area and pressure area, the pore water pressure distribution formula of single well precipitation was constructed according to the energy conservation equation, and the Mindlin solution was introduced to calculate the surface settlement. Verified by the measured data, the average error between the final settlement value and the analytical solution is 15%. The research shows that the model can provide a theoretical basis for surface subsidence caused by precipitation in deep confined aquifer.

Construction impact of a new mined tunnel undercrossing an overlying stormwater box culvert and an underlying existing tunnel

LUO Yunhua, ZHOU Xiangguo, LI Tanglei, ZHANG Yongxing, ZHANG Xuemin

2026, 40(5): 711-716. doi: 10.20265/j.cnki.issn.1007-2993.2025-0276

[Abstract](36) [FullText HTML] (13) [PDF 2045KB](5)

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New underground projects in close proximity to existing underground structures are becoming increasingly common. Strictly controlling the impact of the construction of such new underground works on existing structures is the key to the success of the project. Taking the construction of a new transfer passage tunnel at a subway station, which underpasses an existing tunnel and passes beneath an overlying stormwater box culvert, as a case study, this paper investigates the influence laws of the Center Diaphragm (CD) method on surface settlement and the deformation of both the new tunnel and existing structures. The study is based on field monitoring data and three-dimensional finite element analysis. The results indicate that adopting the CD method—characterized by layered, block, zoned, and segmented excavation—combined with advance horizontal jet grouting for ground improvement, can effectively control ground settlement and structural deformation. Furthermore, the excavation footage in the CD method significantly affects the deformation of the existing tunnel and the stormwater box culvert; therefore, the excavation footage must be strictly controlled during construction to minimize impacts on existing structures. The findings of this study can provide valuable references for the construction of similar underground projects.

Deformation control of a high-fill railway subgrade undercrossed by a three-span frame bridge

FENG Baixi, ZHANG Haihang, ZHOU Kai, JIANG Yihui, XU Xinyang, LI Lang

2026, 40(5): 717-726. doi: 10.20265/j.cnki.issn.1007-2993.2025-0303

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The construction of a box-frame culvert under an existing operational railway embankment may trigger deformation of the existing railway and compromise track smoothness, potentially resulting in operational disruptions in severe cases. This study takes the traffic diversion road beneath the Pingnan Railway at Wuhe Station in Shenzhen as the engineering background. A numerical model of a frame bridge underpassing an existing railway line was established. Based on field monitoring data, the disturbance-induced deformation of the overlying existing railway during cast-in-situ frame bridge construction was analyzed under different pile-cutting sequences. Key control techniques in cast-in-situ box-frame culvert underpass construction were then proposed. The calculation results show that, during the cast-in-situ underpass construction of the frame bridge, the track settlement curves under various construction conditions exhibit a generally symmetrical distribution. The minimum track settlement occurs at the supporting pile locations, whereas the maximum settlement appears at the mid-span of the D-beam. An increase in the span of the frame bridge leads to more pronounced horizontal displacement of the railway track within the bridge span. After optimization of the pile-cutting sequence, the track settlement within the area of the SGC10 supporting pile is significantly smaller than that obtained using the original scheme, with the settlement reduced by 49%. Consequently, both the settlement and horizontal displacement of the existing railway track within the entire underpass area are reduced. By cutting the existing supporting piles in stages, the railway track load can be progressively transferred to different frame bridges, enabling multiple stages of load redistribution. This staged load-transfer process can significantly reduce track settlement and improve the smoothness of the existing railway. The calculated deformation patterns of the railway track under different construction conditions are consistent with the field monitoring results, indicating that the proposed modeling approach can be used to predict track deformation during railway underpass construction at grade-separated crossings and provide practical construction experience for the safe implementation of similar railway underpass projects.

Mechanical degradation behavior and damage constitutive model of muddy siltstone under cyclic wetting and drying conditions

LI Zhi, HAN Lei, HE Xiaoyun, HOU Zhaoxu

2026, 40(5): 727-737. doi: 10.20265/j.cnki.issn.1007-2993.2025-0159

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Aiming at the deterioration of the mechanical properties of mud siltstone in northern Guangxi Province under the action of wet and dry cycles, uniaxial compressive strength tests and SEM tests with different numbers of wet and dry cycles were carried out, and based on the law of energy evolution, the complete compaction point of mud siltstone was determined, and the segmental damage constitutive model of mud siltstone was constructed. The results show that: (1) After five dry and wet cycles, the uniaxial compressive strength and modulus of elasticity of the siltstone decreased by 90.7% and 81.5%, respectively, and the damage mode changed from shear damage to tensile-shear composite damage. (2) The point where the dissipated energy is equal to the elastic strain energy is determined as the complete compaction point, and the compaction strain increases linearly with the increase of the number of dry-wet cycles. (3) The fitting results of the segmental damage constitutive model match well with the experimental data, which can more accurately describe the deformation and damage characteristics of muddy siltstone under the action of wet and dry cycles. The results of the study provide data support and theoretical reference for the stability of slopes subjected to rainfall-exposure cycles in Northern Guangxi.

Mechanism and quantitative characterization of calcareous concretion regulating crack development in expansive soil

HE Lin, ZHOU Bingwei, HUANG Boqing

2026, 40(5): 738-746. doi: 10.20265/j.cnki.issn.1007-2993.2025-0348

[Abstract](38) [FullText HTML] (22) [PDF 2814KB](3)

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In this study, calcareous concretion-like heterogeneities with different area coverage were incorporated into remolded expansive soil, and the Soil Crack Identification System was employed to dynamically monitor and quantitatively analyze the entire process of crack development during dehydration. The test results show that the heterogeneities have a significant influence on the geometric characteristics and development of the expansion soil cracks, systematically regulating quantitative indicators such as crack rate. With the increase of the heterogeneities coverage, the crack initiation and inflection point moisture content occur earlier, and the crack development tends to form a more direct and fewer expansion paths along the boundaries of the heterogeneities, and inhibits the evolution of cracks to wider morphology. Among them, the coverage of 15.7% is the threshold of regulation effect. Under this coverage, the crack rate, total crack length and fractal dimension all reach the maximum value. The influence of heterogeneities on crack development exhibits staged characteristics, with the stress concentration effect, partition constraint effect and interface effect acting together to determine the process of crack emergence, expansion and stabilisation. The research findings can provide a theoretical basis for an in-depth understanding of the mechanism of crack development in heterogeneous soils and related engineering practices.

Influence of pilot hole depth on construction parameters and bearing behavior of pipe piles in saturated clay sites

SHENG Zhiqiang, ZHU Zhaojing, REN Xinjian, MENG Jiahui, LIN Li, QIU Rendong, ZHU Chunming

2026, 40(5): 747-754. doi: 10.20265/j.cnki.issn.1007-2993.2025-0228

[Abstract](61) [FullText HTML] (16) [PDF 889KB](8)

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Taking the saturated clay site as the background, the influence of pilot hole depth on pile installation, soil plugging effect, and bearing performance was systematically analyzed by comparing the construction parameters and single pile static load test results of prefabricated pipe piles (pile length of 9.0 m) with different pilot hole depths (3.0, 4.5, 6.0 m). Key findings include: (1) For jacked pile installation, the final pressure showed minimal variation when pilot hole depths were less than half the pile length (4.5 m), but significantly reduced at two-thirds pile length (6.0 m). In hammer-driven piles, the blow count decreased substantially with pilot hole depth, particularly for the final 80 cm penetration at 6.0 m depth. (2) Increasing pilot hole depth reduced soil plug length in jacked piles but increased it in hammer-driven piles, indicating greater soil intrusion into pile cavities during dynamic installation. (3) The ultimate bearing capacity of single piles decreased with pilot hole depth. Shaft resistance dominated capacity reduction at depths 4.5 m, while both shaft and tip resistances significantly diminished at 6.0 m depth. (4) The experimental ratio of the characteristic vertical compressive bearing capacity to the final jacking force averaged 0.293, approaching the lower bound of 0.30 stipulated in Clause 4.3.3 of the Technical Specification for Static Pressing Precast Concrete Pile Foundations (DBJ/T 15—94—2013). This indicates that the bearing capacity can still be estimated from the final pressure under pilot-hole conditions in saturated clay. In the absence of regional experience, the safety factor should be amplified by 11%~26% relative to the code value. (5) Considering both construction feasibility and bearing-capacity loss control, the pilot hole depth for pipe piles in saturated clay sites is recommended to be 0.4~0.5 times the pile length, which effectively mitigates extrusion effects while limiting capacity reduction. These findings provide a reliable reference for the design and construction of pilot hole techniques for pipe piles in saturated clay strata.

Toughness enhancement mechanism of cement-sodium silicate composites based on fiber bridging and calcium ion regulation

FENG Xiao, HOU Benao, SUN Wen, YANG Wenda, SHI Zhenzhong, ZHANG Shilei, LI Meiling

2026, 40(5): 755-764. doi: 10.20265/j.cnki.issn.1007-2993.2025-0202

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Cement-sodium silicate (C-S) grout struggles to effectively absorb dynamic load energy in practical engineering due to insufficient toughness. To address this problem, a ternary synergistic modification system of CaO-EG-PP was proposed. By regulating calcium ion concentration and the bridging effect of polypropylene (PP) fibers, the effects of different mixing ratios (0%~5% calcium oxide (CaO), 0.04% ethylene glycol (EG), 0%~1% PP fibers) on the mechanical properties of C-S consolidates are investigated. Combined with experiments on setting time, compressive strength, flexural-compressive strength ratio, tensile-compressive strength ratio and impact resistance, the toughness enhancement mechanism is revealed. The results show that when the volume ratio (V_c∶V_s) increases from 2∶1 to 5∶1, the setting time is shortened by 41.2%~54.2%. For the group with 1% CaO + 0.04% EG, the compressive strength reaches 6.75 MPa at a PP fiber content of 0.2%, which is 13.4% higher than that of the control group, and the elastic modulus increases by 36.1% simultaneously. The tensile-compressive strength ratio of the group with 3% CaO + 0.04% EG is increased by 5.4%~104.1% compared with the control group, and the PP fiber bridging effect raises the impact energy consumption at complete cracking to 147.15 J (39.24 J for the control group). The study indicates that optimized calcium ion concentration balances the charge density of silicate tetrahedra to stabilize the gel structure, ethylene glycol strengthens interfacial bonding via hydrogen bonds, and fiber bridging together with topological entanglement inhibits microcrack propagation. The three components synergistically realize the coupled enhancement of ion regulation-hydrogen bond stabilization-fiber toughening.

Strength characteristics of fill material for red clay soft rock roadbed

HE Nengfang, ZHANG Zonghong, HU Ren, MA Jie, HE Xiaoyun

2026, 40(5): 765-771. doi: 10.20265/j.cnki.issn.1007-2993.2025-0158

[Abstract](38) [FullText HTML] (18) [PDF 915KB](5)

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To investigate the influence of particle size and moisture content on shear strength characteristics of red-bed soft rock fillers in roadbed engineering, direct shear tests were conducted on typical red-bed soft rock fillers from Guangxi region under varying particle sizes and moisture conditions, clarifying the influence of particle size and moisture content on the shear strength, brittleness, and dilatancy characteristics of red-bed soft rock fillers. The results revealed that: increasing particle size, moisture content, and vertical load promoted the transition of stress-displacement curves from softening to hardening, accompanied by increased peak shear displacement; shear strength demonstrated a characteristic peak-shape response to moisture variation, while showing monotonic decay with particle size growth; elevated vertical loads and moisture contents facilitated the shear volumetric behavior also transitioned from dilatancy to contraction; particle coarsening, moisture saturation, and load intensification collectively suppressed dilation, with coarser particles exhibiting pronounced pre-shear contraction; brittleness evolution progressed through three-phase coupling with dilation angle: softening-dilation, hardening-dilation, and hardening-contraction, governed by the increasing particle size and moisture content of red-bed soft rock fillers.

Bearing characteristics of reinforced weathered material embankment with waste tyre grating

JIN Long, LI Shenghu, LIU Yazhen, LIU Zhikun, LIU Qingyuan, ZHANG Hongbo

2026, 40(5): 772-779. doi: 10.20265/j.cnki.issn.1007-2993.2025-0149

[Abstract](36) [FullText HTML] (17) [PDF 1647KB](1)

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Waste tyres have high friction resistance and high strength characteristics, and have good application prospects for reinforced fine-grained soil, weathered material, soft rock and other embankments. To reveal the bearing characteristics of reinforced embankment with waste tyre grating under vertical load and establish the calculation method of bearing capacity, we designed and carried out the indoor loading test of reinforced embankment, and studied the bearing characteristics and deformation characteristics of reinforced embankment with waste tyre grating under different number of reinforcing layers, and the results show that: scrap tyre grating can effectively improve the structural integrity of the embankment, and reduce the settlement and lateral displacement of the top of the slope and effectively enhance the ultimate bearing capacity of the embankment, up to 70%; embankment internal stress along the depth of the direction of gradual attenuation, and the upper layer of grating to bear the stress is obviously greater than the lower layer of grating; compared with the impact of the number of layers of grating, it can be seen that the more the number of reinforcing layers, the more obvious the effect of the tyre grating mesh pads, the phenomenon of stress concentration weakened. According to the analysis of the test results, the ultimate bearing capacity calculation formula and parameters of the waste tyre grating reinforced weathering material roadbed are determined, and the study results can provide theoretical support for the application of waste tyre grating engineering.

Shear characteristics of foamed flowable stabilized soil under triaxial compression conditions

ZHAO Dongsheng, WANG Jun, YAO Cuncun, ZHANG Hongbo, CAO Shuxin, TAO Yuchen

2026, 40(5): 780-790. doi: 10.20265/j.cnki.issn.1007-2993.2025-0199

[Abstract](57) [FullText HTML] (25) [PDF 2953KB](14)

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Foamed Flowable Stabilized Soil (FFSS) is widely used in backfill engineering. However, its performance evaluation is mostly based on unconfined compressive strength, with limited studies addressing the influence of lateral confinement. In this study, a series of Unconsolidated Undrained (UU) triaxial shear tests were conducted to systematically investigate the effects of wet density, silt content, and confining pressure on the mechanical behavior of FFSS. The results show that the stress–strain curves of the specimens exhibit distinct elastoplastic characteristics and conform to the Mohr–Coulomb failure criterion. Both increased confining pressure and wet density contribute to enhanced triaxial compressive strength. Specifically, when wet density increased from 600 kg/m³ to 1200 kg/m³, cohesion increased by over 250%, while the internal friction angle decreased with increasing density. Confining pressure was also found to delay post-peak strength degradation, reducing the brittleness index by 40%~60%. A critical silt content of 35% was identified, at which the material achieved optimal strength and deformation performance. Moreover, a multiple regression model for shear strength was developed based on the test data, offering valuable support for the engineering design and performance prediction of FFSS.

Current Issue 2026, Volume 40, Issue 5

Current Issue
2026, Volume 40, Issue 5