几何参数对隧道地震反应影响的二维数值分析  

2-D numerical analysis of tunnels against earthquake loading considering geometrical parameters

作　　者：孙强强[1] 薄景山[1,2] 孙有为[1] 张兆鹏[2] 

机构地区：[1]防灾科技学院,河北三河065201 [2]中国地震局工程力学研究所地震工程与工程振动重点实验室,黑龙江哈尔滨150080

出　　处：《世界地震工程》2017年第4期49-58,共10页World Earthquake Engineering

基　　金：国家自然科学基金(51208108);中央高校基本科研业务费研究生科技创新基金项目(ZY20160302)

摘　　要：隧道结构地震破坏的原因众多,几何因素的影响不可忽视。基于有限差分方法,构建一系列数值计算模型,比较了不同埋深、直径、衬砌厚度和径厚比时隧道结构的地震响应特性,并采用相对变形比和内力放大系数定量分析了隧道的变形、内力分布和内力峰值与几何参数间的关系。计算结果表明:内力放大系数随着埋深的增加而减小,埋深大于20m,输入地震动幅值小于0.2g时,隧道拱顶底间相对位移峰值和相同位置处自由场相对位移峰值接近;衬砌厚度对动弯矩的影响较动轴力显著,增加衬砌厚度会显著的增大隧道的动弯矩峰值,但弯矩放大系数随着衬砌厚度的增加而减小;隧道的动内力峰值随着直径的增加而增大,而轴力放大系数则随着直径的增加而减小;径厚比显著影响衬砌结构的内力分布,当径厚比大于10时,隧道结构发生显著的内力偏转。The effects of geometrical parameters on the seismic response of tunnel in soils are discussed. The dynamic analysis is performed using the finite difference method and the soil behavior is simulated with Mohr-Coulomb elastoplastic model. Numerical models are developed to simulate the seismic response after considering various buried depths, diameters, thicknesses and diameter-to-thickness ratios. It is shown that the internal forces amplification factor is larger at shallow tunnels, and the maximum relative displacement of tunnel crown and invert is approx- imately equal to that of freefield when the depth is larger than 20 m and PGA is less than 0.2 g. Analysis also re- veals that lining thickness has significant influence on the seismic-induced bending moments, but axial forces are limited. The bending moment amplification factor decreases with the lining thickness increasing. The maximum seismic-induced internal forces are larger at big diameter, there is an inverse relationship between the axial forces amplification factor and the diameter. It also can be seen that the diameter-to-thickness ratio affects the internal force distribution of the lining. The tunnel lining has a significant internal force deflection when it is greater than 10.

关 键 词：隧道地震反应 埋深 径厚比 有限差分方法 动力时程分析 

分 类 号：TU4[建筑科学—土工工程]