Abstract:With the method of microscopic statistics,the mechanism of anisotropic sand and impact of bedding angle on sand frictional properties and shear strength are analyzed. Based on the research above,two micro-factors including shear capacity coefficient and stability of particles are studied,which influence the frictional properties and peak strength of anisotropic sand. Moreover,in order to study the action mechanism of these two factors,“plastic hinge-wedge” model is established and a method to calculate the peak friction angle of sand is proposed. Finally,the modified direct shear test indicates that the theoretical results coincide with the experimental ones well. Results are hence obtained:(1) The orientation arrangement of internal particles is the main factor to cause the anisotropy,and the inherent anisotropy and induced anisotropy have the same formation microscopic mechanism;(2) The bedding angle has a great influence on the distribution of particle direction angle and affects the macroscopic mechanical properties of sand;(3) The bearing capacity of sand is mainly affected by the distribution of particle direction angle,the stability of particles and the friction properties of particle surface. These three factors lead to the ultimate strength of soil which can be calculated.
陈立平,张顶立,房 倩,应国刚,王剑晨. 基于细观统计的各向异性砂土摩擦特性与破坏机制研究[J]. 岩石力学与工程学报, 2014, 33(sl): 3291-3298.
CHEN Liping,ZHANG Dingli,FANG Qian,YING Guogang,WANG Jianchen. RESEARCH ON FRICTION CHARACTERISTICS AND FAILURE MECHANISM OF ANISOTROPIC SAND BASED ON MICRO-STATISTICS. , 2014, 33(sl): 3291-3298.