摘要
针对活动断层错动下隧道安全性难题,以常见的马蹄形隧道为例,通过开展室内模型试验以及三维数值仿真计算,分析活动断层错动下隧道变形特征,确定重点设防和监测区段以及隧道断面上的重点监测位置。结果表明:活动断层走滑错动下,围岩、衬砌沿隧道走向变形规律基本一致,即上盘区域整体变形保持一致,与施加的断层错动量大小基本一致;围岩、衬砌的整体变形沿隧道纵向呈逐级递减趋势,最后稳定且趋于0。随着错动量的增大,断层错动的影响区域逐渐扩大,变形递减的斜率逐渐增大,围岩变形沿纵向变化模式逐渐由指数衰减向线性衰减过渡,当走滑量小于等于1 m时,围岩的潜在破坏区域约为30 m;随着错动量增大至2、3、4 m时,围岩变形近似呈线性且向远离断层方向逐渐衰减。建议监测穿越活动断裂隧道时对断层上盘30 m内重点变形监测,监测隧道断面时根据实际情况适当加强拱腰的应力监测。
In response to the safety challenges of tunnels under active fault movement,taking the common horseshoe shaped tunnel on the Kunming-Nanning high speed railway as an example,the indoor model tests and threedimensional numerical simulation calculations were conducted to analyze the tunnel deformation characteristics under active fault movement,to determine the key fortification and monitoring sections and key monitoring positions on the tunnel section.The results show that under the strike-slip displacement of active faults,the deformation patterns of surrounding rock and lining along the tunnel direction are basically consistent,that is,the overall deformation of the hanging wall area remains consistent,and the magnitude of the applied fault deformation is basically consistent.The overall deformation of the surrounding rock and lining shows a gradual decreasing trend along the longitudinal direction of the tunnel,and finally stabilizes and tends to zero.As the displacement increases,the affected area of fault deformation gradually expands,and the slope of deformation decreasing gradually increases.The longitudinal variation pattern of surrounding rock deformation gradually transitions from exponential decay to linear decay.When the strikeslip is less than 1 m,the potential failure area of the surrounding rock is about 30 m.As the displacement increases to 2,3 and 4 m,the deformation of the displacement curve is approximately linear and gradually decays away from the fault direction.It is suggested that the key deformation monitoring should be carried out within 30 m of the hanging wall of the fault when the tunnel crossing active fault is monitored.In the process of tunnel section monitoring,stress monitoring of the arch waist should be increased appropriately according to the actual situation.
作者
周栓科
戴天
马素健
于佳琪
程素明
ZHOU Shuanke;DAI Tian;MA Sujian;YU Jiaqi;CHENG Suming(Sichuan Expressway Construction and Development Group Co.Ltd.,Chengdu 610031,China;Wenzhou Railway and Urban Rail Transit Construction Management Center,Wenzhou Zhejiang 325000,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Chengdu Branch of China Railway No.3 Engineering Group Co.Ltd.,Chengdu 610031,China)
出处
《铁道建筑》
北大核心
2023年第5期110-114,共5页
Railway Engineering
基金
中铁二院工程集团有限责任公司科研项目(科2019-023)。
关键词
隧道
活动断层
模型试验
数值模拟
变形特征
设防区段
tunnel
active fault
model testing
numerical simulation
deformation characteristics
fortified section
