隧道软弱围岩变形特征与控制方法  

Deformation Characteristics and Control Method of Tunnel with Weak Surrounding Rock

作　　者：李鹏飞[1,2] 赵勇 刘建友 

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124 [2]首都世界城市顺畅交通协同创新中心,北京100124 [3]5铁道部工程设计鉴定中心,北京100844 [4]中铁工程设计咨询集团有限公司,北京100055

出　　处：《中国铁道科学》2014年第5期55-61,共7页China Railway Science

基　　金：国家自然科学基金资助项目(51308012);北京市自然科学基金资助项目(3144026);城市与工程安全减灾教育部重点实验室基金资助项目(USDE201407)

摘　　要：根据隧道围岩变形发生的机制可将其分为材料变形和结构变形;根据隧道围岩变形的时空效应可将其分为掌子面超前变形、掌子面挤出变形和掌子面后方变形。隧道软弱围岩变形具有一般隧道围岩变形的特性,同时还具有初期变形速度较快、变形持续时间长、变形破坏形式多样,以及超前变形及其影响范围、掌子面挤出变形和掌子面后方变形及其影响范围均较大等特点。为控制掌子面超前变形,可以利用钢管、钢棒、钢背板材料系或高压喷射系等隧道横、纵向刚性梁构造进行超前支护;为控制掌子面挤出变形,可以采用倾斜(或球形)掌子面、预留核心土、掌子面喷混凝土、掌子面打设锚杆、掌子面前方围岩注浆加固等方法;为控制掌子面后方变形,可以优化开挖方法,采用喷射高性能混凝土、选用高承载力锚杆、高规格钢支撑以及施加多重支护等方法提高初期支护的承载能力。According to the forming mechanism, the surrounding rock deformation of tunnel can be divided into material deformation and structure deformation. Based on the space-time effect on the tunnel face by excavation, the deformation distribution of surrounding rock is divided into three parts in space, which are deformation ahead of the tunnel face, at the tunnel face and back from the tunnel face. Besides the general characteristics of the common tunnel, high change rate in initial excavation period, long-lasting deformation, various failure modes, the large change range ahead of the tunnel face, at the tunnel face and back from the tunnel face are considered as the main characteristics of the soft surrounding rock tunnel. In order to control the deformation ahead of the tunnel face, transverse or vertical rigid beam structures formed by steel tubes, steel bars, steel backing plate, or high pressure grouting, etc can be taken as support measures in advance. In order to control the deformation at the tunnel face, countermeasures such as inclined or orbicular tunnel face, reserved core, shotcrete on the face, advance anchor bolt and advanced grouting can be adopted. In order to control the deformation back from the tunnel face, the excavation method should be optimized, meanwhile such measures as shotcrete with high performance concrete, anchor with high bearing capacity, high standard steel support and multiple support, etc should be adopted to improve the bearing capacity of the primary support.

关 键 词：铁路隧道 软弱围岩 围岩变形 时空效应 变形控制 

分 类 号：U45[建筑科学—桥梁与隧道工程]