在已经开发的3D-FSM·DDM间接边界元数值模拟系统的基础上,进行含预紧力端锚固锚杆支护功能的数值模拟系统研究与开发。算法的基本思想是:根据岩体与锚杆重合部分两端点的位移差与锚杆相应部分两端点的轴向位移差相等,补充方程数量,并与其他单元在边界条件下联立求解全部虚拟应力未知量;求取后利用其进一步求解围岩任意点的应力、位移及稳定性。所开发的数值系统与FLAC3D数值模拟系统进行了比较,验证本边界元系统的可靠性。开发后的边界元数值模拟系统可广泛应用于矿山、隧道等大型岩土工程的围岩稳定性分析。
A new numerical method simulating the support of partially grouted bolts with pre-tightening force was proposed on the previous researches of indirect boundary element method of 3D-FSM·DDM. According to that the displacement difference between the two ends of the bolt hole is the same as the deformation of anchor bolt at the relative section from the axis direction,the induced displacement equations about the bolt hole and the bolt were established. With the stress equilibrium equations in the original system,all the unknown quantities about the fictitious stresses can be solved. Finally,the stress,displacement and stability at an arbitrary point of rock around roadway can be computed. The correctness of the method was proved by comparing with the numerical simulation results with FLAC3 D. The numerical simulation system of boundary element developed can be widely applied in the stability analysis of large scale geotechnical engineering such as mine,tunnel,etc.