四川省屏山县新安镇红土滑坡滑带土抗剪强度参数反演分析

摘要

Determination of the shear strength parameters of sliding zone soils is significant for the estimation and evaluation of landslide stability.Taking the clay landslide observed at Xin`an town of Pingshan County in Sichuan province as an example, the parameters of sliding zone soils are determined by the inversion shear strength parameters and the measured parameters of the sliding zone soil based on mechanical test.The results show that cohesive strength C and friction angle φ can be affected strongly by the constraints of critical state.The difference in the sensitivity to landslide stability is large for the shear strength parameters C and φ.The landslide stability is less sensitive to cohesive strength C and more sensitive to friction angle φ.Moreover, the obtained shear strength index (C=13.5 kPa, φ=8.5°) is consistent with that measured by mechanical test.%滑坡滑带土抗剪强度参数选取对滑坡稳定性计算及其评价至关重要.以四川省屏山县新安镇红土滑坡为例,通过反演分析计算滑带土抗剪强度参数(粘聚力C,摩擦角φ值),并结合滑带土的力学试验测出的参数,综合确定滑带土抗剪强度参数指标.结果表明,滑带土抗剪强度参数粘聚力C值和摩擦角φ值受临界状态约束条件影响较大,且粘聚力C值、摩擦角φ值对滑坡稳定性敏感程度差异性较大,滑坡的稳定性对粘聚力C值的敏感性较低,对摩擦角φ值的敏感性较高,并得出了抗剪强度指标:C=13.5 kPa,φ=8.5°,与力学试验测出的抗剪强度参数值相比,结果基本一致.