Stability analysis and optimization of excavation method of double-arch tunnel with an extra-large span based on numerical investigation  

作　　者：Yiguo XUE Huimin GONG Fanmeng KONG Weimin YANG Daohong QIU Binghua ZHOU 

机构地区：[1]Geotechnical and Structural Engineering Research Center,Shandong University,Jinan 250061,China

出　　处：《Frontiers of Structural and Civil Engineering》2021年第1期136-146,共11页结构与土木工程前沿（英文版）

基　　金：Much of the research presented in this paper was supported by the National Natural Science Foundations of China(Grant Nos.51379112,51422904,40902084,41772298,and 41877239);the Fundamental Research Funds for the Central Universities(No.2018JC044);the Shandong Provincial Natural Science Foundation(No.JQ201513).

摘　　要：The Xiamen Haicang double-arch tunnel has a maximum span of 45.73 m and a minimum burial depth of 5.8 m.A larger deformation or collapse of the tunnel is readily encountered during tunnel excavation.It is therefore necessary to select a construction approach that is suitable for double-arch tunnel projects with an extra-large span.In this study,three construction methods for double-arch tunnels with extra-large spans were numerically simulated.Subsequently,the deformation behavior and stress characteristics of the surrounding rock were obtained and compared.The results showed that the double-side-drift method with temporary vertical support achieves better adaptability in the construction of such tunnels,which can be observed from both the numerical results and in situ monitoring data.In addition,the improved temporary support plays a critical role in controlling the surrounding rock deformation.In addition,the disturbance resulting from the excavation of adjacent drifts was obvious,particularly the disturbance of the surrounding rock caused by the excavation of the middle drift.The present findings can serve as the initial guidelines for the construction of ultra-shallowly buried double-arch tunnels with extra-large spans.

关 键 词：double-arch tunnel triple-layer composite liner system numerical modeling stress analysis SETTLEMENT 

分 类 号：U45[建筑科学—桥梁与隧道工程]