巷道围岩弹塑性解析解及工程应用

Elastic-plastic analytical solutions for surrounding rocks of tunnels and its engineering applications

基于统一强度理论和非关联流动法则,合理考虑中间主应力、围岩塑性区弹性应变和剪胀特性等影响,建立了巷道围岩弹塑性应力和位移解析解。研究结果表明:中间主应力和围岩剪胀特性对围岩特征曲线和支护压力的影响显著,考虑中间主应力的影响能充分发挥围岩的强度潜能;不考虑塑性区体积变化所得支护压力较小,设计偏危险;巷道支护设计应考虑围岩剪胀特性的重要影响。

Based on the unified strength theory and a non-associated flow rule,the elastic-plastic analytical solutions of stress and displacement for surrounding rocks of tunnels were presented.The effects of intermediate principal stress,elastic strains in the plastic zone and dilatancy properties were taken into account in the analytical solutions.The results show that the influences of intermediate principal stress and dilatancy properties on the ground reaction curve and support pressure are significant.The strength potentials of rock mass are better achieved due to considering the intermediate principal stress effect.The tunnel design with ignoring volume changes in the plastic zone is in danger,in that the corresponding support pressure is smaller.The effect of dilatancy is important for the tunnel support design.