单向压缩条件下圆形颗粒体含孔洞试样的力学模拟

Numerical simulation of mechanical behavior of a specimen composed of circular granular material

通过编程,用连续介质快速拉格朗日分析(FLAC)实现了圆形颗粒体在单向压缩条件下的力学行为模拟.颗粒体试样中间含一圆形孔洞,颗粒体被离散成正方形网格,若2个颗粒体发生接触,则需要在颗粒体之间预置界面.研究了施加的荷载对试样应力线、应变线及受拉破坏区域等的影响.结果表明,试样内部的最大压应力约为所施加压应力值的5倍,这有别于连续介质理论的结果.孔洞顶部及底部各有1个三角形受拉区,内部可见明显的拉裂纹,裂纹的长度随试样端部所施加应力的增加而增大.

Fast Lagrangian analysis of continuous media（FLAC） is made to model the mechanical behavior of a specimen composed of circular granular material in uniaxial compression.The specimen has a central circular hole.The granular is divided into rectangular elements.If two granular bodies contact,an interface between them is needed.Effects of stress level applied at the top of the specimen on the stress line,strain line and tensile failure region are studied.Results show that the maximum tensile stress is about five times as high as the applied stress at the top of the specimen.This result is obviously different from the result of the continuous media theory.In the roof and floor of the hole,two triangular tensile stress regions are observed,in which apparent tensile cracks are formed.The length of the crack is increased with increase of the applied compressive stress at the top of the specimen.