基于无量纲法的应变软化围岩的逐步位移法解析
Dimensionless analysis of numerical stepwise procedure in strain-softening rock mass

基于Brown等提出的应变软化模型及逐步应变计算方法，采用无量纲分析法，获得基于Mohr-Coulomb准则下的应变软化围岩的应力及位移场分布的无量纲解。与已有理论结果的对比分析表明：采用基于无量纲法的逐步位移法求解软化围岩应力与位移是准确有效的。对支护力及残余区控制系数的影响分析表明：支护力和残余区控制系数的增大会减小围岩塑性区范围。该结论可为隧道支护力大小的设计提供参考。
On the base of numerical stepwise procedure and the strain-softening behavior model which is proposed by Brown, this study uses the dimensionless analysis method and obtains the dimensionless solution of the stress and displacement in strain-softening rock mass compatible with the generalized Mohr-Coulomb (M–C) failure criterion. Compared with the existing theory, results show that the solution of the stress and displacement in strain-softening rock mass based on dimensionless numerical stepwise procedure are validity and accuracy. The analysis of the supporting force and control coefficient in residual region show that the plastic region will decrease as the supporting force and control coefficient in residual region increase. This conclusion can provide a reference for the design of tunnel support force