【摘要】 针对含初始缺陷的既有地铁隧道受邻近穿越隧道施工影响的首都地铁隧道工程背景,基于有限差分方法,通过对既有地铁车站结构受邻近隧道穿越后的抗震性能研究,揭示其抗震动力响应机理。结果表明,在邻近隧道穿越影响下,含初始缺陷的既有隧道各薄弱控制点在地震作用下位移和应力动力时程的波动趋势具有相似性,说明衬砌结构是整体运动的,其位移、应力较穿越前均有所增加,边墙和仰拱在穿越后抗震性能影响最大,剪切破坏主要以车站结构周边土体为主,新线穿越后其剪切破坏分布范围有所增大,应进行注浆加固处理,与自身结构刚度相匹配,提高抗震能力。更多还原

【Abstract】 For the engineering background of a typical subway tunnel with initial defects caused by the construction of the new down-through tunnels in Beijing,the aseismatic performance of the existed tunnel is studied so as to reveal the mechanism of seismic dynamic response by using finite difference method.Numerical model will firstly be established.Then its boundary conditions and initial conditions are considered,including the choice of related parameters and seismic wave at the same time.The numerical simulation results show that the tunnel is deforming in its entirety since such physical variables as displacement and stress in its all key weak points have the same dynamic tendency under the influence of approaching construction of tunnels,and the variables including displacement and stress are much larger than those without any influence.For examples,after down-through construction,much influences of aseismatic performance are mainly taking place at both the side wall and the upper arch;and the shearing damage are mainly doing in surrounding soil mass.Due to widely shearing damage after down-through construction,it is suggested that grouting reinforcing should be applied so as to make them much stiffness as a whole and to have good aseismatic performance.更多还原