基于复杂地质的长大隧道快速施工关键技术探讨  

Investigation of the Rapid Construction Based on the Complex Geology at the Tunnel

作　　者：欧阳艳[1] 高攀科 OUYANG yan;GAO Panke(Shanxi Pailway Institute,Weinan,Shanxi714000 China;Chang ’An University,Xi’an,Shanxi710000,China)

机构地区：[1]陕西铁路工程职业技术学院,陕西渭南714000 [2]长安大学,陕西西安710000

出　　处：《公路工程》2018年第3期168-172,共5页Highway Engineering

基　　金：陕西省教育厅自然科学基金项目(12JK0926)

摘　　要：针对复杂地质环境下长大隧道施工难度大,施工周期长的问题,以西北高原地区一长大隧道实际施工情况为对象,结合FLAC 3d数值软件进行隧道开挖快速施工分析。根据隧道埋深开挖损伤理论提出了以岩爆段为支护对象的柔性防护网快速施工法。研究结果表明:隧道埋深小于300 m,并不为产生岩爆;隧道埋深300~800 m时,存在轻微岩爆;隧道埋深800~1 000 m时,以中级岩爆为主;当埋深大于1 000 m时,以严重岩爆为主;当隧道开挖时,隧道后墙角区域的岩爆倾向明显大于拱顶和边墙区域。其中拱肩区主要以中级岩爆为主,拱脚区域完全满足强岩爆特性;通过运用柔性防护网快速施工法,利用柔性网的延性降低骨料回弹,提高了混凝土的喷射厚度,将柔性网与围岩密贴,能减缓和控制岩爆发生;利用柔性网系统实现了局部荷载的均匀传递,提高局部减弱区的防护能力,改善隧道结构的耐久性。In view of the complex geological environment grew up in the tunnel construction is difficult and long construction cycle,grew up a tunnel construction situation in northwest plateau area as the object,combining with the FLAC 3 d numerical software for rapid construction of tunnel excavation.Based on the theory of tunnel buried deep excavation damage,the paper puts forward the rapid construction method of the flexible protective network with the rock burst section as the support object. The results show that the tunnel buried depth is less than 300 m,which is not to generate rock burst. When the tunnel is buried deep 300 ~ 800 m,there is a slight rock burst; When the tunnel is buried at 800 ~ 1 000 m,it is dominated by intermediate rock burst. When depth is greater than 1 000 m,it is mainly caused by severe rock burst. When the tunnel is excavated,the rockburst tendency in the corner area of the tunnel is obviously greater than that of the arch and the wall. The arch shoulder area is mainly dominated by intermediate rock burst,and the arch region is completely satisfied with the strong rock burst characteristics. By using flexible shield construction method,using the ductility of flexible network to reduce the aggregate rebound,improve the thickness of the concrete jet,will stick,flexible network and surrounding rock can slow and control of rock burst occurred; By using the flexible network system,the uniform transfer of local load is realized,and the protection ability of local weakening zone is improved,and the durability of tunnel structure is improved.

关 键 词：长大隧道 快速施工 柔性防护网 

分 类 号：U455[建筑科学—桥梁与隧道工程]