基于内动力的非均匀岩石材料I型断裂扩展过程分析

天然岩石材料由不同矿物组成同时包含孔洞、裂隙等微结构面,组成材料和结构非均匀。载荷作用下的破坏主要是由于这种非均匀性所致,引入内动力的概念,分析非均匀岩石材料裂纹扩展、演化规律。根据裂纹扩展的内外区概念,选定结构非均匀即含有预制裂纹的岩石材料,对于内区材料的均匀和非均匀性分别进行计算,分析其裂纹扩展过程。从计算结果可以看出:内区材料均匀岩石即只有结构非均匀时,裂纹扩展沿预制裂纹平直扩展,内动力的最大值始终位于裂纹的尖端,各个时步裂纹扩展长度相同;内区材料非均匀即结构、材料都不均匀时,裂纹扩展不再平直而是成锯齿状延伸,应力状态图不规则,成散射状,在原有裂纹扩展到一定程度后不再沿预制裂纹扩展,而是产生新的开裂点。

Propagation process analysis of I type fracture on non-uniform rock based on internal motive force

Natural rock material of different mineral composition contains holes,cracks,and other surface microstructure,is the non-uniform materials of composition and structure.The rock damage on loading is mainly due to this non-uniform.Authors introduced the concept of the internal motive force,analyzed the fracture propagation and involution law of the non-uniform rock material.According to the concept of the inside and outside region on the fracture propagation,authors selected the non-uniform structures rock material that was containing pre-crack,a uniform and non-uniform in the area of the material were calculated to analyze the fracture propagation process.The results show that crack propagation is along the pre-crack straight extension and the maximum value of the internal motive force is always at the crack tip and the crack length is the same as each time step when the uniformity material of the inside region rock that is only non-uniform structure;crack propagation is no longer straight but in a zigzag extending,the irregular stress state diagram,extends a certain length after the original crack is no longer along the pre-crack extension,but to generate new cracking point when the inside region material is non-uniform that is the structure and material are both non-uniform.