背后组合空洞对隧道衬砌结构安全性影响评价研究

Research on the evaluation of the influence of combined cavity on the safety of tunnel lining structure

运用Midas/GTS NX软件模拟,在固定埋深情况下,分析了隧道拱顶、拱腰、拱脚衬砌位置背后各30°范围的三种组合空洞(拱顶+右拱脚、拱顶+右拱腰、右拱脚+右拱腰)下的应力分布及结构安全系数变化情况,结果表明:组合空洞的存在使得衬砌结构内力发生显著变化的同时结构整体安全系数都有所减小,其中右拱脚(30°)+右拱腰(30°)组合空洞工况的结构整体安全系数最低,最不安全位置出现在拱顶部位及拱腰部位,仰拱部位安全系数相对较高;且三种组合空洞工况下对结构右侧整体安全影响更显著。

The paper used Midas/GTS NX software to simulate,at a fixed burial depth,the three combined voids(vaults)in the range of 30 behind the tunnel arch,arch waist,and arch foot lining are analyzed+right arch foot,arch top+right arch waist,right arch foot+right arch (waist)stress distribution and structural safety factor changes.The results show that the presence of combined voids makes the internal force of the lining structure change significantly while the overall safety factor is reduced,and the overall safety factor of the right arch foot(3°)+right arch waist(3°)combined cavity working condition is the lowest;the most unsafe position appears at the top of the archand the waist of the arch and the safety factor of inverted archis relatively high;the three combined void conditions have amore significant impact on the overall safety of the right sideof the structure.