岩体中孔与裂纹贯通破坏模式图形判别法

Graphic Discrimination Method of Coalescence and Failure Mode in Rock Mass with Hole and Crack

为研究工程岩体贯通破坏过程岩体裂纹起裂贯通机制,预制了以岩桥倾角为变量的红砂岩试块用单轴压缩的加载方式进行实验,并且通过数值模拟进行验证.首先总结了含单裂纹与单孔红砂岩岩石试块破坏的4种断裂模式,然后首次定义了塑性核心区半径、塑性延展区长度,并用它们表征单孔半径(或裂纹长度、倾角)与塑性破坏区域的大小,发现塑性破坏区的贯通与试块的贯通断裂具有很好的对应关系,最后提出通过作图判断岩石裂纹贯通断裂的判别方法.模拟结果验证了所提破坏模式判别方法的正确性,与类似物理实验结果具有一致性.

In order to study the crack initiation and coalescence of the failure process of rock mass,the uniaxial compression of red sandstone samples with various rock bridge angles was numerically performed. Four failure patterns of red sandstone samples with single crack and hole is firstly summarized,then the radius of the plastic core and plastic extension area are defined,the single span radius（ or the crack length,angle） and the size of the plastic damage area are characterized. It is found that the coalescence of plastic failure zone is well consistent with the coalescence and fracture of samples. Finally,a graphic discrimination method is proposed to discriminate the fracture mode of rock mass. The experimental results verify the correctness of the method of the failure mode,which is consistent with the results of similar physical tests.