含岩腔板岩隧道塌方成因及治理  

Collapse Mechanism and Countermeasures of Tunnel Passing Through Slate Cavity

作　　者：魏家旭 周文皎 刘睿迪 李知军 白明洲[4] WEI Jiaxu;ZHOU Wenjiao;LIU Ruidi;LI Zhijun;BAI Mingzhou(Yunnan Construction Investment Holding Group Co.Ltd.,Kunming 650501,China;Railway Engineering Research Institute,CARS,Beijing 100081,China;State Key Laboratory of Track System for High-speed Railway,CARS,Beijing 100081,China;School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]云南省建设投资控股集团有限公司,昆明650501 [2]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081 [3]中国铁道科学研究院集团有限公司高速铁路轨道系统全国重点实验室,北京100081 [4]北京交通大学土木建筑工程学院,北京100044

出　　处：《铁道建筑》2023年第12期111-116,共6页Railway Engineering

基　　金：云南省交通运输厅科技项目(云交科教[2018]35号);中国铁道科学研究院集团有限公司基金(2022YJ126)。

摘　　要：针对古那湾1号隧道穿越含岩腔板岩发生的塌方,分析了塌方成因和破坏模式并给出了综合治理措施。隧道塌方成因是层状板岩碎裂松散、自稳能力低,隧顶围岩有岩腔发育和连续降雨导致围岩强度明显降低。破坏模式为隧道开挖→岩腔底部沉积物结构破坏进而推挤隧道→隧道垮塌→隧址区塌陷。治理措施包括:对岩腔进行回填;自地表垂直向下打设钢花管并注浆,增加围岩强度并封堵雨水渗流路径;洞内打设超前大管棚和小导管注浆预加固地层以及开挖过程中在掌子面及时喷射混凝土等。通过数值模拟与现场监测发现塌方治理效果较好。隧道已顺利贯通并处于长期稳定状态。Based on the collapse of the Gunawan No.1 Tunnel passing through slate cavity,the collapse mechanism was analyzed,and countermeasures were proposed.The main reasons for collapse are loose and fragmented layered slate with low self-stabilization ability,and a significant strength decrease of the surrounding rock due to the slate cavity and continuous rainfall.The damage mode is tunnel excavation→damage of the sediment at the bottom of the slate cavity,pressured the tunnel→tunnel damaged→collapse of the tunnel site area.The countermeasures are as follows:backfill slate cavity,drill steel tube pipes vertically downwards from the surface and inject grout to increase the strength of surrounding rock and block the path of rainwater seepage,then advanced large pipe sheds and small conduits are installed inside the tunnel to pre-reinforce the strata through grouting,and concrete is sprayed in a timely manner on the face during excavation.Through numerical simulation and on-site monitoring,it is found that the collapse countermeasures are effective,and the tunnel is successfully constructed and in a long-term stable state.

关 键 词：隧道塌方 板岩岩腔 塌方成因 治理措施 钢花管注浆 

分 类 号：U458.3[建筑科学—桥梁与隧道工程]