基于Abaqus对断层错动下高速铁路隧道衬砌受力变形模拟研究

Research on Mechanical Deformation Characteristics of High-speed Railway Tunnel LiningStructure under Fault Movement

以杭温高速铁路某区间隧道为研究对象,采用Abaqus软件建立三维分析模型。通过对断层上、下盘强制施加位移边界条件,分析断层错动下铁路隧道衬砌结构受力变形机制,探究不同断层位错量、断层宽度及倾角下衬砌结构弯矩、应力和竖向位移的变化规律。结果表明,由于断层上下盘的相对错动导致隧道衬砌结构的弯矩、应力和竖向位移变化都会在断层破碎带附近发生激烈波动;衬砌左、右拱腰处主应力峰值在围岩与断层破碎带交界处出现最大和最小值,且其值随着断层位错量的增大而进一步增大;在一定的断层宽度和位错量下,衬砌拱腰处会产生拉应力和压应力,导致衬砌结构极易发生弯曲变形以及拉扭破坏。

Taking a section tunnel of Hangzhou-Wenzhou high-speed railway as the research object,a three-dimensional analysis model is established by using Abaqus software.By imposing displacement boundary conditions on the upper and lower walls of the fault,the influence of fault movement on the mechanical deformation characteristics of highway tunnel lining structure is studied.The change laws of bending moment,stress and vertical displacement of lining structure under different fault movement amount,fault width and inclination are analyzed.The results show that the bending moment,stress and vertical displacement of the tunnel lining structure will fluctuate violently near the fault fracture zone due to the relative displacement of the upper and lower walls of the fault.The maximum and minimum principal stress peaks at the lining arch waist occur at the interface between the fault fracture zone and the surrounding rock,and their values increase with the increase of fault dislocation.Under a certain fault width and movement amount,tensile stress and compressive stress will occur at the arch waist of the lining,which will lead to bending deformation and tensile torsional failure of the lining structure.