三维主应力条件下隧道应变软化围岩弹塑性解  

Elastoplastic Solution for Strain-softened Surrounding Rocks in Tunnels under 3D Principal Stress

作　　者：王凯[1] Wang Kai(The Fifth Engineering Co.,Ltd.of China Railway 18th Bureau Group,Tianjin 300450,China)

机构地区：[1]中铁十八局集团第五工程有限公司,天津300450

出　　处：《市政技术》2023年第2期91-97,共7页Journal of Municipal Technology

摘　　要：为探究隧道在三维主应力作用下的围岩应变及位移,将塑性区内相等的径向应力增量划分为有限个相同数量的同心圆环,通过平衡微分方程和差分进化算法,利用三维H-B屈服准则确定每一环的应力。基于求解的应力和相关联流动法则可以获得塑性区的塑性应变及位移。将计算结果与有限元软件的数值模拟结果进行对比验证其可靠性。结果表明,笔者所建立的三维主应力条件下隧道应变软化围岩弹塑性解是一种可以同时求解3个主应力及位移数值解的新方法,且与数值模拟结果拟合良好,证明了该方法的可靠性与准确性。相对于二维平面应变假设,该方法更好地考虑了岩体三维主应力状态下的应力应变关系,对复杂岩层条件下的隧道围岩稳定性分析具有重要参考价值。In order to investigate the strain and displacement of the surrounding rock in the tunnel under 3D principal stress, the equal radial stress increments in the plastic zone is divided into a finite number of concentric rings of the same size. The stresses in each ring is determined by 3D H-B criterion, the balanced differential equation and the differential evolution algorithm. The plastic strain and displacement can be obtained based on the solved stresses and the associated flow law. The calculation results are compared with the numerical simulation results of finite element software to verify the reliability. The results show that the elastic-plastic solution of the tunnel strain-softened surrounding rock under 3D principal stress is a new method of solving three principal stresses and displacements simultaneously. It fits well with the numerical simulation results, which proves the rationality and accuracy. Compared with 2D plane strain assumption, this method better considers the stress-strain relationship under the 3D principal stress state of the rock mass. It has important reference value for the stability analysis of the tunnel surrounding rock under complex rock conditions.

关 键 词：三维H-B屈服准则 相关联流动法则 应变软化围岩 弹塑性解 

分 类 号：U451.2[建筑科学—桥梁与隧道工程]