级配碎石直剪试验的细观分析

基于颗粒流理论及其PFC2D程序,在细观层次上从数值分析角度研究了碎石的直剪试验,从而揭示了其抗剪强度和变形机理。研究中针对碎石提出了一种随机计算模型,并给出了随机模型的实现方法,同时对该随机模型的算法可靠性进行了验证。文中探讨了在直接剪切试验中碎石的抗剪强度随位移的变化以及最大粒径、竖向压力对其影响,并从细观力学的角度上描述了直剪试验过程中颗粒的运动机理。直剪试验过程中的碎石细观结构变化的颗粒流仿真,是关于碎石细观力学特征与宏观力学响应相关联的初步研究。

Micro-Mechanical Analysis for Direct Shear Tests of Grade Crushed Stones

On the basis of the theory and procedure of Particle Flow Code in 2 Dimensions(PFC2D in this paper),Direct Shear Tests(DST) of crushed stone are studied by numerical analysis from the viewpoint of microcosmic to obtain the shear strength and deformation mechanism.A random calculation model for crushed stone is suggested and carried out,and its algorithmic reliability is verified.The varieties of the shear strength with displacement,and vertical pressure in DST are studied separately,and the movement mechanism of the particle during the DST process from the viewpoint of micromechanics is described.The numerical simulation of particle flow for crushed stone during the DST process is just an initial study on micro-mechanical characteristics and macro-mechanical response.