土岩复合地层大跨地铁车站地震响应特征研究

为了研究位于土岩复合地层的大跨地铁车站在地震作用下的动力响应特征,采用有限元软件建立地层-结构模型,分别用Drucker-Prager弹塑性模型和混凝土损伤破坏模型模拟岩土体和混凝土衬砌,并在数值模拟的同时输入水平和竖向地震动进行动力时程分析。基于数值计算结果,对车站结构关键点的最大和最小主应力时程、关键时刻的主应力分布状态等进行分析,结果表明:1)车站结构最大拉应力主要发生在中板腋角、边墙上部和拱底等拐角区域;2)结构破坏主要表现为受拉损伤破坏;3)结构的压应力相对较小,未出现明显的受压破坏。

Research on Seismic Response of the Subway Station in Rock and Soil Strata

In order to study the dynamic response of a subway station in rock and soil strata under earthquake,finite element software is adopted to establish strata-structure mode.In addition,Drucker-Prager elastic-plastic model and the damage model for concrete are adopted to describe lining of the surrounding rock and concrete.During the numerical simulation,dynamic time history analysis is carried out through horizontal and vertical motion input.Based on the numerical results,the time histories of principal stresses,distribution of principal stresses at particular moments are fully studied.The resultsshow that:1)the largest tensile stress generally occurs at corners of floorslab,the top of sidewall and the bottom of the subway station;2)structural damage is mainly presented by tensile damage;3)tensile stress of the structure is relatively low,no obvious tensile damage occurs.