考虑非线性峰后损伤的圆形巷道围岩稳定性分析

Stability Analysis on Circular Roadway Considering Nonlinear Post Peak Damage

为研究巷道围岩的稳定性,考虑围岩损伤后弹性模量的变化,采用统一强度准则,对巷道围岩进行极限平衡状态分析,推导出巷道损伤区半径及应力分布的解析表达式,通过算例分析损伤区弹性模量、中间主应力和扩容对理论解的影响。结果表明:损伤区半径随扩容系数的增大而增大;随着损伤区弹性模量的增大,损伤区半径逐渐增大,切向应力峰值逐渐减小且距离巷道壁面越远;中间主应力系数越大,损伤区半径越小,切向应力峰值越大且离巷道壁面越近。

In order to study the stability of surrounding rock of roadway, considering the change of elastic modulus after damage,the limit equilibrium state analysis of surrounding rock mechanics state is carried out by using the unified strength criterion. Theanalytic expressions of damage zone radius and stress of surrounding rock are deduced. In the case study, the effect of elasticmodulus of damage zone, intermediate principal stress and dilatation are analyzed by the theory of solution. The results show thatthe damage zone radius will be increased with the increase of dilatation coefficient; with the increase of the elastic modulus ofdamage zone, the radius of damage zone will be increased gradually and the peak of tangential stress will be decreased graduallyand farther to roadway; the bigger the intermediate principal stress coefficient is, the smaller the radius of damage zone is, and thepeak of tangential stress is larger and closer to the roadway.