高频循环剪切下结构与松砂接触面的土体特性

摘要

The behavior of loose sand-structure interface under the high frequency cycle shearing is analyzed by using Particle Discrete Element Method (DEM). The changes of sand box porosities of DEM model and sand volume strains are examined in detail. The results show that sand volumetric shrinkage due to shearing is not obvious in spite of the larger loose sand particle friction coefficients and particle stiffness. The particle stiffness ratio has a little effect on the mechanical properties of sands. In addition,the decrease in volume of sand under shearing is more obvious with the increase of the confining pressures. Moreover,the decrease in volume of loose sand under shearing is greater with the increase of the high frequency cycle shear amplitude and the shear frequency.%应用颗粒离散元分析理论,深入地研究了高频循环剪切荷载下松砂与结构的接触面土体响应特性,对各种颗粒因素和剪切条件对接触面土体孔隙率和体应变的影响进行详细分析.数值仿真分析结果表明,松砂颗粒摩擦系数和颗粒刚度越大,接触面附近土体剪缩性越不明显；松砂的颗粒刚度比对其力学性质影响不大；边界围压越大,松砂的剪缩性越明显；高频循环剪切的剪切振幅和剪切频率越大,松砂的剪缩性越强.