考虑中间主应力影响的非饱和黄土边坡抗滑桩间距研究

Spacing of anti-slide piles in unsaturated loess slope taking into account the influence of intermediate principal stress

理论研究和工程应用中土体破坏准则的合理选用对研究和设计结果影响较大,同时由于中间主应力效应的影响,导致平面应变试验和常规三轴试验的试验结果的差异也被广泛证实。基于土拱破坏理论,采用理论推导的方式将统一强度理论、统一滑移线场理论和土拱破坏理论应用于非饱和黄土边坡抗滑桩间距研究中,并根据试验数据确定了非饱和黄土中间主应力参数b,推导了基于土拱理论的非饱和黄土边坡抗滑桩间距表达式。通过工程实例研究了非饱和黄土边坡抗滑桩间距随中间主应力参数b和基质吸力的变化规律。研究结果表明,考虑中间主应力效应的影响可增大抗滑桩设计间距,从而降低工程造价。研究对优化非饱和黄土地区抗滑桩间距具有重要的参考价值。

Soil failure criteria in theoretical research and engineering applications have a significant impact on research and design outcomes.Additionally,the discrepancy in experimental results between plane strain tests and conventional triaxial tests,attributed to the influence of intermediate principal stress,has been widely acknowledged.In this study,the unified strength theory,unified slip line field theory,and soil arch failure theory are employed to investigate the anti-slide pile spacing of unsaturated loess slopes.Based on experimental data,the intermediate principal stress parameter b of unsaturated loess is determined,and the anti-slide pile spacing expression for unsaturated loess slopes is derived using the soil arch theory.Furthermore,the relationship between anti-slide pile spacing variation,intermediate principal stress parameter b,and matrix suction of unsaturated loess slopes is explored through engineering case studies.The analysis indicates that considering the effect of intermediate principal stress can lead to an increase in the design spacing of anti-slide piles,thereby reducing engineering costs.This research provides valuable insights for optimizing anti-slide pile spacing in unsaturated loess regions.