单轴压缩下带圆孔的脆性岩板劈裂破坏研究  

Splitting Cracks from Brittle Rock Plate with Circular Cavities under Uniaxial Compression

作　　者：邓林[1] 张志敏[2] 

机构地区：[1]黄山学院建筑工程学院,黄山245041 [2]湖南科技大学土木工程学院,湘潭411201

出　　处：《硅酸盐通报》2017年第6期2006-2010,共5页Bulletin of the Chinese Ceramic Society

基　　金：安徽省高校自然科学研究项目(KJHS2015B04);安徽省教育厅教学研究项目(2016jyxm0975)

摘　　要：带圆孔的脆性岩板在单轴压缩荷载的作用下,其破坏过程一般经历弹性阶段,劈裂裂纹的产生与扩展,压剪裂纹的产生及岩板破坏几个阶段。分析了弹性阶段的圆孔四周的应力分布,解释了劈裂裂纹的产生机理,确定了劈裂裂纹产生的位置。通过分析开裂后裂纹尖端应力强度因子的变化规律,发现随着孔径的增大,起裂荷载减小,这个结论与实验结果非常吻合。而对于同一模型随着裂纹的扩展,应力强度因子减小,反映了劈裂裂纹的扩展是稳定的。对于岩石这种内部存在很多微小孔洞或不连续面的材料,通过该模型能从宏观唯像上解释岩石在单轴压缩试验中的劈裂破坏机理。Under uniaxial compression, the failure process of the brittle rock plate with single cavity generally contains the following several stages： elastic stage, initiation and propagation of splitting cracks, the growth of compression shear mixed mode cracks and rock breaking. The mechanical mechanism and initiation location of splitting cracks were demonstrated through the analysis of the stress distribution around the holes and mechanical properties of the brittle rock plate. It is obtained that cracking load decreases with the increase of the aperture, and the result fit well with the experimental result. At the same time, the splitting crack extension is stable because the crack stress intensity factor is decreasing when the crack propagate. It is shown that the proposed model is capable of explaining the fracture mechanism of the rock which is full of micro-holes and discontinuous surface.

关 键 词：脆性岩板 劈裂裂纹 应力强度因子 起裂荷载 

分 类 号：TU375[建筑科学—结构工程]