山岭公路隧道CD法开挖过程安全稳定性分析  

Safety and stability analysis of mountain highway tunnelexcavation by CD method

作　　者：惠冰 王琳 张文俊 陈朋 赵忠孝 HUI Bing;WANG Lin;ZHANG Wenjun;CHEN Peng;ZHAO Zhongxiao(Shandong Transportation Institute,Jinan 250102,China;Traffic Institute,Shandong University of Science and Technology,Qingdao 266590,China)

机构地区：[1]山东省交通科学研究院,山东济南250102 [2]山东科技大学交通学院,山东青岛266590

出　　处：《浙江工业大学学报》2024年第1期86-92,共7页Journal of Zhejiang University of Technology

基　　金：国家重点研发计划项目(2016YFC0801600);山东省交通运输厅科技计划项目(2021B40)。

摘　　要：不良地质条件下大断面隧道的开挖常采用CD法,在开挖过程中,完成最后一部台阶开挖后隧道全断面成型,这时需要及时对断面进行支护,以防止诱发隧道局部大变形甚至坍塌。为了预防隧道局部大变形或坍塌的发生,笔者以济潍高速某山岭隧道CD法开挖为研究对象进行全过程动态监测,采用有限元软件MIDAS 2020对台阶法开挖最后一部进行全过程的高仿真度模拟。研究结果表明:隧道沉降、收敛监测所得到的实测拟合曲线与有限元软件计算所得的模拟曲线基本吻合,通过选择合适的开挖步长,CD法开挖能够有效减小拱顶沉降和洞壁的收敛。短台阶法开挖和适时支护是控制隧道围岩变形,保证其安全稳定的关键,可以有效地保证浅埋大断面隧道的安全与长期的稳定。The CD method is usually used in the excavation of large-section tunnels under unfavorable geological conditions.During the excavation process,the whole section of the tunnel is formed after the last step excavation.At this time,the section needs to be supported in time to prevent the local large deformation or even collapse of the tunnel.In order to prevent local large deformation or collapse of the tunnel,the author takes the CD method excavation of a mountain tunnel in Jiwei expressway as the research object to carry out the whole process dynamic monitoring,and the finite element software MIDAS 2020 is used to carry out the high simulation of the whole process of the last step excavation.The results show that the high simulation curve obtained by tunnel settlement and convergence monitoring is basically consistent with the calculation curve.The CD excavation method can effectively reduce vault settlement and convergence of tunnel wall by selecting appropriate excavation step.Short bench excavation and timely support are the key to control the deformation of tunnel surrounding rock and ensure its safety and stability,which can effectively ensure the safety and long-term stability of shallow buried large section tunnel.

关 键 词：CD法 山岭隧道 数值模拟 监测 

分 类 号：U456[建筑科学—桥梁与隧道工程] U451.2[交通运输工程—道路与铁道工程]