摘要
为了研究顺层岩质边坡下浅埋偏压隧道洞口段围岩破坏机理,以班丘隧道为例,根据现场地质调查结果,结合监测数据并利用数值模拟的方法分析了隧道洞口段围岩的破坏机制,提出了治理措施。结果表明:隧道浅埋侧拱肩处易出现拱形拉伸屈服塑性带,围岩易从此处开始破坏;围岩破坏是多种因素共同作用的结果,其中隧道偏压作用、岩体结构和降雨是造成隧道塌方和边坡滑坡的关键因素;隧道塌方模式为:掌子面上方岩体首先在重力作用下沿拱形屈服带形成拱形坍塌,然后在弯折内鼓作用下形成整体塌方,边坡滑坡的形式为坡体表面中风化页岩夹泥砂岩在坡体破坏的情况下发生顺层面的近平面滑移。
The Banqiu tunnel is taken as an example to study the failure mechanism of surrounding rock at shallow tunnel entrance section subjected to the unsymmetrical pressure loading from bedding rock slope.Based on the results of on-site geological survey,combining with the monitoring data and numerical simulation method,the failure mechanism of surrounding rock in tunnel entrance is analyzed,and the control measures are proposed.The research shows that the arch-shaped tensile yield plastic zone is easy to appear at the shoulder of shallow-buried side arch of tunnel,and the surrounding rock is easy to be damaged from this point.The failure of surrounding rock is a result of multifactor synergism.Tunnel biasing,rock mass structure and rainfall are the key factors causing tunnel collapse and slope landslide.The mode of tunnel collapse is that the rock mass above the working face falls along the arch yield zone to form an arch collapse under the action of gravity at first,and then an overall collapse under the action of bending and inner drum is formed.The mode of the slope landslide is that the medium weathered shale with thin layered mudstone slides along the surface of bedding plane in the case of slope failure.
作者
于群群
刘秀敏
郑允
YU Qun-qun;LIU Xiu-min;ZHENG Yun(School of Civil Engineering & Architecture,Anhui University of Science & Technology,Huainan 232001,China;State Key Laboratory of Geomechanics & Geotechnical Engineering,Institute of Rock & Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China)
出处
《河南城建学院学报》
CAS
2020年第1期58-63,70,共7页
Journal of Henan University of Urban Construction
基金
国家自然科学基金资助项目(11602284)。
关键词
浅埋隧道
偏压
顺层边坡
数值模拟
破坏机理
shallow tunnel
unsymmetrical pressure
bedding slope
numerical simulation
failure mechanism
