岩质隧道围岩压力影响因素分析

Analysis of Influence Factors on Surrounding Rock Pressure of Rocky Tunnel

采用经典理论公式法、解析计算和数值模拟分析3种途径详细分析了隧道埋深、初始地应力、跨度、侧压力系数、隧道断面形状及岩体物理力学参数对隧道围岩松动压力的影响规律。结果表明:当围岩处于弹性状态时,围岩松动压力与隧道埋深、初始地应力和岩体容重呈线性正比关系;围岩竖向松动应力与侧压力系数呈线性反比关系,而水平向应力与侧压力系数呈线性正比关系;隧道断面形状对围岩松动压力有一定影响;岩体变形模量、黏聚力、内摩擦角和泊松比对围岩松动压力的影响可以忽略。同时,分析了这些方法的不足之处。

Adopting the classical theoretical formula method,the analytical calculation and numerical simulation,this paper analyzed the influence rules of tunnel embedded depth,initial geostress,span length,lateral pressure coefficient,tunnel section shape and rock physical mechanical parameters on surrounding rock loosening pressure of tunnel.The results show that when surrounding rock is in elastic state,loosening pressure of surrounding rock has positive linear relationship with tunnel embedded depth,initial geostress and bulk density of the rock mass;vertical loosening pressure of surrounding rock has inverse linear relationship with lateral pressure coefficient,while horizontal stress has positive linear relationship with lateral pressure coefficient;tunnel section shape has a certain influence on loosening pressure of surrounding rock;the effect of rock deformation modulus,cohesion,internal friction angle and Poisson＇s ratio on loosening pressure of surrounding rock can be neglected.Meanwhile,the disadvantages of these methods are discussed in this paper.