基于Hoek-Brown强度准则的巷道围岩弹塑性研究

摘要

The surrounding rock zoning and analysis are the main basis to determine the roadway bolting and loose ground pressure. Displacement of surrounding rock is the main parameter for the design of coal mine tunnel cross section and the determination of distortion geostatic pressure. This paper adopts Hoek-Brown strength theory and limit equilibrium equation and carries out the elasto-plastic analysis of an idealized roadway surrounding rock with a unit lateral pressure coefficient. It derives the plastic zone radius, stress field and displacements of the surrounding rock. The results are further compared with the results determined from the widely used Fennner formula associated with the Mohr-Coulomb yield strength criterion.%巷道围岩区域划分和分析是确定巷道里锚杆支护、松散地压的主要依据.巷道围岩位移是煤矿巷道断面设计、确定变形地压等的主要根据.本文采用Hoek-Brown强度理论和极限平衡方程通过对侧压力系数为1的圆形理想巷道的巷道围岩进行弹塑性分析.通过上述计算求出围岩巷道的塑性半径、应力及位移,与目前广泛采用的以Mohr-Coulomb为屈服强度准则的修正的芬纳公式作为比较.