上下近接地下结构在地震作用下的动力响应分析

摘要

在地震作用下,探究上下近接、最小竖向净距2 m——地下商场和地铁车站的危险截面和相互影响规律.结合地铁抗震规范相关要求确立该工程的6种计算工况,建立三维模型运用时程分析法进行计算得出:相比两个结构单独存在,上下近接组合形式的结构动力响应均发生了一定量的增幅;结构构件距两结构相邻面越近,动力响应的增幅越大.因此,两个结构相邻面是地震发生时的危险截面.上下近接的地下结构的相互影响规律和危险截面等结论对以后的设计、施工能起到一定的指导作用.%This paper studies the dangerous cross-section and interaction law of the underground store and subway station with upper and lower closely-attached and minimum vertical net distance of 2.0 m under seismic action.With reference to metro related requirements specified in seismic code,six calculation conditions are defined and a three-dimensional model is established for analysis.Time history analysis method is used to conduct calculation and conclude that in comparison of the two separated structures,the dynamic responses of all upper and lower closely-attached underground structures tend to have a certain amount of increase,and the closer of structural elements to the adjacent surface of the two structures,the bigger the increase of dynamic responses.Therefore the adjacent surface of the two structures is the dangerous cross section subject to earthquake.The conclusions involving upper and lower closely-attached underground structure's interaction law and dangerous cross section may provide some guidance to future design and construction.