Crack propagation in brittle solid containing 3D surface fracture under uniaxial compression

Abstract

用含有预制半圆形三维表面裂纹的冷冻透明有机玻璃材料研究了裂纹的扩展机制,并对裂纹扩展中的特征应力进行了分析,同时,考察了裂纹深度、长度和倾角等几何因素变化对裂纹扩展的影响。研究结果表明,表面裂纹扩展受裂纹深度 d 与试样厚度 T 影响很大,当 d/T≥1/3时,表面裂纹扩展到接近试样端部并穿透到试样的背面,当 d/T<1/3时,其裂纹扩展长度为预制裂纹直径的0.5～1倍时就不再扩展;裂纹倾角和裂纹相对试样尺寸也影响裂纹扩展。 The purpose of this study is to investigate the effect of crack length,flacture angle and boundary effect on the mechanisms of propagation of a half-disk shaped 3-D surface crack under uniaxial compression. Transparency material of PMMA is used in this study.The results of this study can provide a better understanding on the instability of mine pillar.