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.
出处
《石河子大学学报（自然科学版）》
CAS
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)
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
single-arch four-lane road tunnel
span-ratio
cross-section optimum
finite difference software FLAC
