黄土连拱公路隧道围岩变形监测和数值分析  

Site Monitoring and Numerical Analysis on Surrounding Rock Deformation of the Loess Double-arch Highway Tunnel

作　　者：胡晋川[1] 谢永利[1] 杨晓华[1] 聂少锋[1] 

机构地区：[1]长安大学,西安710064

出　　处：《武汉理工大学学报（交通科学与工程版）》2010年第1期101-105,共5页Journal of Wuhan University of Technology（Transportation Science & Engineering）

基　　金：国家西部交通建设科技项目资助(批准号:200131800021)

摘　　要：以离军高速公路黄土连拱隧道为工程背景,对地表沉降、地质和支护状况、拱顶下沉和水平收敛进行了现场监测,并采用有限元方法分析了隧道围岩拱顶下沉和水平收敛的变化规律,进而研究了黄土连拱隧道三导洞法施工的围岩变形规律和影响因素.结果表明:黄土隧道IV类围岩比V类围岩变形小,围岩稳定较快;三导洞施工法开挖中、左、右导洞和断面开挖时,围岩应力一直处于重新调整中,变形也在不断变化,且施工中开挖顺序对围岩变形有很大影响,在洞室开挖施工中,要密切注意拱腰及拱顶的变形情况,加强V类围岩监测,及时进行临时支护,尽早完成右洞初期支护,以防变形过大而围岩失稳;影响黄土隧道围岩变形的主要因素是黄土的工程特性和地质工程环境.Based on the doubled-arch tunnel loess of the Lijun highway, the surface settlement, geology and support status, vault crown settlement and horizontal constringency are monitored in site. Then the finite element method is used to analysis the rules of vault crown settlement and horizontal con- stringency of surrounding rocks. The deformation rule of surrounding rocks of the doubled-arch tun- nel with the three heading construction method is studied in this paper. The results shows that the de- formation of tunnel with Grade IV of surrounding rocks which stabilized rapidly is relatively small than that of Grade V. When middle pilot heading, left pilot heading, right pilot heading and section excavation are excavated, the stress of surrounding rocks has being in readjust and deformation is constantly changing. Besides, the order of construction has great influence on the deformation of sur- rounding rocks. Therefore, during the cavern excavation of tunnel, the deformation of haunch and vault should be closely noted. In order to prevent surrounding rock instability induced with large de- formation, the surrounding rocks of Grade V should be monitored tightly, the temporary support should be made timely and the primary right tunnel support should be completed as early as possible. The major reasons that influence the deformation of surrounding rocks of the loess tunnel are the char- acteristic of loess and the circumstance of project geology.

关 键 词：黄土连拱隧道 三导洞施工法 变形监测 变形规律 有限元 

分 类 号：TU451.2[建筑科学—岩土工程]