绕顶转动模式下三维被动土压力的数值研究

已有的刚性挡土墙上三维被动土压力的研究主要基于挡土墙平移模式(T位移模式)下开展的,而对挡土墙绕顶转动模式(RT位移模式)下三维被动土压力的研究尚不充分。因此,该文采用数值方法系统地研究了RT位移模式下三维被动土压力及三维空间滑裂面性状。针对无黏性土体,得到了挡土墙宽度与深度比值、土体摩擦角大小和墙土接触面摩擦角比值对三维被动土压力系数及墙后土体滑裂面的影响,并与T位移模式下的三维被动土压力系数和墙后土体的空间滑裂面形态进行了定量的比较。研究结果表明:RT位移模式下的三维被动土压力系数和空间滑裂面形态均受土体内摩擦角及墙土接触面摩擦角比值的影响,且两者之间存在相互联系。RT位移模式下的三维被动土压力系数和空间滑裂面形态与T位移模式下有显著的区别;RT位移模式下的三维被动土压力系数及空间滑裂面相比于T位移模式下较小。研究成果可为RT位移模式下三维被动土压力的进一步研究和相关工程设计提供参考。

NUMERICAL STUDY OF 3D PASSIVE EARTH PRESSURE DURING WALL ROTATION AROUND THE TOP MODE

The existing study of 3D passive earth pressure on the rigid retaining walls is mainly based on translation mode(T mode) of the retaining wall,while the study of 3D passive earth pressure during retaining wall rotation around the top mode(RT mode) still remains insufficient. Therefore,this paper systematically studies 3D passive earth pressures and the properties of 3D spatial slip surface in RT mode with numerical method. For the non-cohesive soil,the width and depth ratios of retaining wall,the values of soil internal friction angle and the soil-to-wall interface friction ratios have effects on the 3D passive earth pressure coefficients and the slip surface of soil behind retaining walls. Meanwhile there is a quantitative comparison between RT mode and T mode. The results show that: both values of soil internal friction angle and soil-to-wall interface friction ratios have significant influence on the 3D passive earth pressure coefficients and the spatial slip surface behind retaining wall in RT mode,and there is a connection between them. The 3D passive earth pressure coefficients and the spatial slip surface have significant difference between T mode and RT mode. The 3D passive earth pressure coefficients and the spatial slip surface in RT mode are smaller than those in T mode. The results can provide a reference for further study of 3D passive earth pressure and related engineering design in RT mode.