摘要
在断层活动中,粘滑断层的错动往往能够引发地震,能量随错动快速释放,产生较强的地震。断层错动速率是反应断层活动强弱的因素,影响断层内衬砌内结构受力、变形和破坏。以内马铁路一期项目三标段2号隧道为工程依托,运用ANSYS软件数值建模,数值分析断层竖向错动速率与断层破碎带交界面动摩擦系数对穿越断层隧道的竖向位移和第一主应力的影响。结果表明,断层竖向错动是隧道主动盘竖向位移的主要影响因素,动摩擦系数对其影响较小。断层竖向错动导致隧道断层处截面底部拉应力最大,易发生拉裂破坏。增加断层竖向错动速率增加会增大隧道断层处截面底部拉应力,扩大隧道衬砌受拉范围,不利于隧道衬砌的安全。断层动摩擦系数和断层竖向错动速率增加会引起隧道断层处截面第一主应力峰值增加。
In fault activity,the dislocation of stick slip fault can often cause earthquakes,and the energy is released rapidly with the dislocation,resulting in strong earthquakes.Fault displacement rate is a factor reflecting the strength of fault activity,which affects the stress,deformation and failure of lining structure in fault.Based on the No.2 tunnel in the third tender section of the first phase of the Neima Railway,the numerical model of ANSYS software was used to consider the change of the fault friction velocity and the dynamic friction coefficient at the interface of the fault fracture zone.The effect of vertical fault action on the vertical displacement and the first principal stress across the fault tunnel was analyzed.The results show that the vertical fault displacement is the main factor affecting the vertical displacement of the tunnel active disk,and the dynamic friction coefficient has little effect on it.The vertical displacement of the fault leads to the maximum tensile stress at the bottom of the section of the tunnel fault,which is easy to crack.Increasing the vertical displacement rate of the fault will increase the tensile stress at the bottom of the section at the fault of the tunnel,expand the tensile range of the tunnel lining,which is not conducive to the safety of the tunnel lining.The increase of the dynamic friction coefficient and the vertical displacement rate of the fault will lead to the increase of the peak value of the first principal stress at the fault section of the tunnel.
作者
祁彬溪
王凡
陈捷翎
QI Binxi;WANG Fan;CHEN Jieling(School of Resources and Safety Engineering,Central South University,Changsha 410083,China)
出处
《建筑结构》
CSCD
北大核心
2020年第S02期753-758,共6页
Building Structure
基金
国家自然科学基金研究项目(51674287)
关键词
铁路隧道
断层错动
错动速率
动摩擦系数
railway tunnel
strike slip fault
dislocation rate
dynamic friction coefficien
