压剪条件下预埋椭圆裂纹三维扩展实验研究

本文首先试制了透明的低温树脂材料和非透明的砂浆类材料.然后,通过实验研究了这两种材料内置椭圆形裂隙的三维始裂、扩展过程及其破裂过程中声发射信号特征,并采用三维断裂理论确定了内部裂纹的三维始裂状态.实验结果表明,在单轴压缩荷载作用下,两种材料中内置裂隙初期破裂面形态基本一致,均为一对反对称的包裹状翼裂纹,但初始起裂位置有...

EXPERIMENTAL STUDY ON THREE-DIMENSIONAL(3-D) PROPAGATION FROM A PRE-EXISTING ELLIPSE FLAW UNDER COMPRESSION-SHEARING

Some testing samples with a pre-existing ellipse flaw(b/a=0.5) are made from two self-fabricated non-transparent mortar and transparent resin materials.Under uniaxial compression,a series of observation experiments on the 3-D fracture process of the flaw are carried out.The experimental results show that the primary crack shapes are basically similar in the two different materials,namely a pairs of antisymmetric wrapping wing cracks;however,their initial fractured places are different.In the transparent res...