齿坎式挡土结构抗滑稳定性分析

Numerical analysis for stability against sliding of retaining wall with notched sill

采用D-P弹塑性薄层单元模型数值模拟方法,结合现场试验结果对齿坎式挡土结构抗滑稳定性进行了计算分析,数值计算结果表明,挡墙的基底滑动过程、抗滑力和齿前土压力等力学特性指标与实测结果相吻合.进而分析了齿坎长度、位置、基底土特性等因素对齿坎式挡墙抗滑稳定性的影响程度;分析表明,齿坎式挡土结构物滑移破坏形态与刚体极限平衡法的假定存在差异,现行的抗滑稳定性与抗倾覆稳定性分别验算的方法是偏于不安全.

The lamina FEM for Doucker-Prager elasto-plastic model was used for analysis of the stability against bed-sliding for retaining wall by numerical simulation; the results of which accorded well with test results. Consequently, the stability of the retaining wall was discussed for the sliding factors of soil characteristics, load action position, notched-sill in length and position, etc. The calculation result show that the stability of retaining wall increased with the length of notched sill; and that the suitable length was 0.7～1.0 m. The bed failure surface of the retaining wall with notched sill is different from the usually designed sliding surface; the stability against sliding decreased with overturning moment. So analysis for retaining wall against sliding should not neglect the effect of coupling against overturning.