单拱四车道公路隧道断面的优化  

Cross-section Optimum Investigation of Single-arch Four-lane Road Tunnels

作　　者：曾宜江[1] 杨小礼[1] 

机构地区：[1]中南大学土木建筑学院,湖南长沙410075

出　　处：《石河子大学学报（自然科学版）》2008年第5期616-620,共5页Journal of Shihezi University(Natural Science)

基　　金：交通部四车道公路隧道科研项目(200631878557)

摘　　要：合理的扁平率对大断面隧道稳定性和经济性具有重要的意义。本文以广东省龙头山隧道为工程背景,采用大型有限差分软件FLAC,对不同埋深、不同围岩条件下的四车道公路隧道进行了数值模拟,计算出单拱四车道公路隧道围岩的位移、塑性区分布和最大剪切应变率,分析了扁平率对隧道断面的力学特征影响规律,得出以下结论:单拱四车道公路隧道的扁平率应控制在0.61～0.63,这既能满足初期支护条件下围岩稳定性要求,又能提高隧道建设的经济效益。Reasonable span-ratio has an important effect on configuration stability and economical nature of large-span tunnel.Numerical simulation have been conducted using finite difference software FLAC for four-lane road tunnel under different embedded depth and different surrounding rock condition.This paper,based on Longtou Mountain Tunnel in Guangdong province,displacement,plastic zone distribution and maximum shear strain-rate of the surrounding rocks had been calculated for four-lane road tunnel,the influence law of span-ratio on mechanical character of tunnel section had been studied.The results show that span-ratio of single-arch four-lane road tunnel should be controlled in a narrow range of 0.61～0.63,which not only satisfies the stabilization of the surrounding rocks,but also increases economic benefits of tunnel construction.

关 键 词：单拱四车道公路隧道 扁平率 断面优化 有限差分软件FLAC 

分 类 号：U452.2[建筑科学—桥梁与隧道工程]