高围压下岩石椭圆裂纹面构型变化规律

Research on deformation of crack surface of rock masses under high confining compression

采用复变函数和保角变换的方法,对受压条件下张开型裂纹面的变形规律进行了分析,得出了变形过程中裂纹面新构型的参数方程,并给出了新的裂纹面构型的保角变换关系式;考虑到椭圆裂纹面在高围压下产生的较大变形,采用几何非线性的分析方法分析了构型方程参数的理论解,并与小变形线性方法的结果进行了对比分析,表明采用小变形结果误差不大.扩充了受压条件下岩石张开型裂纹的非奇异断裂理论,为研究受压条件下裂纹面的闭合规律和裂纹变形对断裂破坏规律的影响提供了理论依据.

The law of the deformation of the open crack surface under compression is researched. The methods of complex function and conformal transformation are combined to construct the parameter function which describes the deforming crack surface. Furthermore, the new expression of conformal transformation for the deformed crack is deduced to analyze the characteristics of closure and fracture of the open crack. Considering the large deformation of crack surface under high confining pressure, geometric non-linear analysis method is utilized to fix the parameters, whose results are contrasted with those by linear analysis method, and it is shown that little error is caused by small deformation assumption. Based on the proposed method, the deformation of crack surface is calculated under any loads, which shows validity of conclusion. The above result develops the theory of nonsingular fracture mechanics, which will provide the theoretical basis both for the study of closing law of crack surface under compressive loading and the study of the crack deformation＇s influence on the crack＇s breaking.