方家湾衬砌黄土隧道围岩结构地震动稳定性分析

为了得到天平铁路段方家湾黄土隧道在地震作用下的安全系数,在现有文献基础上,借助有限元软件和强度折减法将时程分析应用于隧道结构的地震动稳定性分析,从而获得隧道结构的动力安全系数.通过数值算例,考虑隧道衬砌结构的弹塑性本构关系,利用动力有限元静力强度折减法对有衬砌黄土隧道进行地震动稳定性分析,结合天平铁路土建一标段方家湾隧道工程,对该黄土隧道进行动力稳定性分析,定量估计天平铁路部分黄土隧道地震动的安全储备情况.为以后黄土隧道围岩结构在地震作用下安全系数的计算及其工程应用提供了理论依据.

Analysis of the Seismic Stability of Wall Rock Structure of Loess Lining Tunnel in Fangjiawan of Tianping Railway under Earthquakes

Based on the available literature, and strength reduction method,and the time history with the help of finite element software ANSYS and the analysis method,the seismic stability of the tunnel structure in Fangjiawan section of Tianping Railway was analyzed,thus getting its safety factor. Through numerical examples,and considering the elastic-plastic nature of its lining structure, using the dynamic finite element static strength reduction method, the seismic stability of the lining loess tunnel and analyzed, com- bining it with Fangjiawan tunnel engineering. The dynamic stability of this loess tunnel was also analyzed, and the security situation of the railway of Tianping loess tunnel was quantitatively estimated, so as to pro- vide a theoretical basis for the calculation of safety factors and engineering application under earthquake actions.