大断面隧道施工力学响应数值模拟研究

The numerical simulation of constructional mechanical responses of highway tunnel with large cross section

结合重庆市在建大坪隧道的工程地质和设计情况,对隧道洞身Ⅲ类围岩地段采用不同施工方法锚喷初支开挖时的力学动态响应进行了数值模拟,分析了围岩应力场、应变场、位移场,以及锚喷时喷层、锚杆的力学性态,通过综合比较得出,台阶三分部法开挖是适合大坪隧道Ⅲ类围岩段合理的施工方法。

According to the design and geological condition of Da-ping tunnel, numerical methods used to analyze the mechanical responses of tunnel with large cross section on surrounding rock condition of class Ⅲ. Then stress field , meet an emergency field , displacement field and mechanical responses of shotcrete and bolt support of different construction methods are studied, and base on compare synthetically step three branch excavating method is the rational construction of Da-ping tunnel surrounding rock condition of class Ⅲ.