岩石剪切断裂面接触算法的开发与应用

Development and application of contact algorithms for rock shear fracture surface

为了克服现有数值计算方法在计算复杂断裂面接触滑移过程中效率低的问题,通过吸收边界元的建模思想,提出了新的数值计算方法。在该算法中,所有网格均位于岩块的边界,利用显示差分方法计算得到岩块之间的相互作用力以及岩块的位移量。利用"小球在抛物面上滑移"、"哑铃在不同倾角的斜面上"两个模拟试验对文中的算法进行验证,同时利用文中算法与有限元算法对直剪试验进行模拟。结果表明:算法能够准确描述物体之间的相互接触,准确计算得到接触块体之间的法向位移。算法能够准确判断出接触物体的"滑移状态"和"稳定状态",摩擦力的数值计算结果与解析解的误差小于10-10。在计算断裂面接触和剪应力变化规律时,算法与有限元算法的计算结果一致,但文中计算方法的效率显著提高。

In order to overcome the inefficiency of existing numerical calculation programs in calculating the contact slip law of complex fracture surfaces,a new numerical calculation method was proposed by absorbing the idea of boundary element method.In this algorithm,all grids were located at the boundary of rock blocks,and the interaction force between rock blocks and the displacement of rock blocks were calculated by using the explicit difference method.The algorithm was validated by two simulation experiments,i.e.the ball sliding on the parabolic surface and the dumbbell sliding on the inclined surface with different inclinations.The results show that:the algorithm can accurately describe the contact between objects and accurately calculate the normal displacement between blocks.The algorithm can accurately judge the"sliding state"and"stable state"of the object.The error between the numerical and analytical results of friction force is less than 10-10.When calculating the variation of bearing capacity during slip of fracture surface,the calculation results of the new method are consistent with those of the finite element method,but the calculation efficiency of the new method is significantly improved.