考虑中间主应力与约束损失的深埋圆形隧道围岩特征曲线分析

提出基于统一强度理论和非相关联流动法则,推导同时考虑中间主应力和约束损失两种因素作用下的围岩弹塑性应力-位移解析解.结合算例,分析中间主应力和约束损失对围岩特征曲线的影响规律.结果表明:考虑中间主应力的影响,能够充分发挥围岩的强度;考虑约束损失的影响,计算得到的围岩塑性区径向位移值减小,说明在利用围岩特征曲线进行支护设计时,同时考虑以上两种因素,能够取得较好的经济效益.

Ground Reaction Analysis of Deep-Buried Circular Tunnels Considering Intermediate Principal Stress and Confinement Loss

Based on the unified strength theory and a non-associated flow rule, an analytical solution for elastic-plastic of a deep circular rock tunnel is presented taking into consideration both effects of the intermediate principal stress and confinement loss factor. In combination with a calculation example, the impacts of these two factors on the ground reaction curve from are studied. The results show: consideration of the impact of intermediate principal stress is conducive to develop the strength of the surrounding rock; considering the impact of the constraint loss, the radial displacement of surrounding rock decrease. Consequently, when two factors are considered, using the characteristic curve of surrounding rock for designation, benign economic benefit can be achieved.