脆性材料在压缩载荷作用下的断裂破坏准则

目前多裂隙材料在压缩载荷作用下的力学行为问题已成为当前断裂力学及岩石力学等学科的重要课题.选取位于同一直线上的多裂隙体,考虑裂隙(纹)表面间的摩擦力并应用复变应力函数,推出了裂纹应力强度因子的解析表达式.当只有两个裂纹或一个裂纹存在时,给出了准确的应力强度因子解析解.最后依据共线双裂纹模型和单裂纹模型及传统的裂纹断裂准则,建立了脆性材料在压缩载荷作用下的断裂破毁准则.在一些特殊情况下, 这个准则可以简化,并且其简化后的准则具有应用价值,特别是当材料不含有宏观裂纹时,这个准则就和著名的库伦 - 摩尔准则相一致.

A New Fracture Criterion for Brittle Materials Under Compression

In this paper, the cracks situated along a straight line were investigated, and using complex stress functions, the stress intensity factors were formulated.For the two cases of only two collinear cracks and a single crack inside an infinite plate, the exact solutions of stress intensity factors were presented. Finally, by using the two collinear crack model and a single crack model, a new fracture criterion for brittle materials under compression was developed based on the traditional fracture criterion. In some special cases, this new crack propagation criterion can be simplified, and the results were very interesting, especially, for the case of materials without pre existing macrocracks, the new crack propagation criterion was identical with the well known Coulomb Mohr criterion.