近场地震竖向分量对LRB基础隔震结构地震响应影响分析

发布时间：2018-03-06 00:02

本文选题：近场地震　切入点：竖向地震动　出处：《工程力学》2016年04期 　论文类型：期刊论文

【摘要】：该文主要对比分析了近场区竖向地震动对LRB基础结构动力响应的影响。首先,在ABAQUS有限元软件中建立了较为精确的有限元模型:上部结构采用纤维模型以考虑隔震结构在近场地震作用下可能出现的塑性变形,隔震层采用能反映隔震支座水平和竖向力学性能相互耦联的"Ryan-Kelly"力学模型;同时,综合考虑隔震支座的剪切破坏和拉压破坏以确定支座的破坏界限;在此基础上,分别进行隔震结构在水平地震单独作用和水平竖向地震联合作用下的动力分析,对比分析结果可知:近场区竖向地震动对于隔震支座的破坏模式影响较大,在较大的竖向分量作用下,隔震支座可能会在剪切破坏之前先发生拉压破坏;对于上部结构的动力响应,竖向地震动的影响具有随机性,但同样不可忽略,在某些工况下,考虑竖向地震作用会较大幅度地降低其水平动力响应。
[Abstract]:In this paper, the effect of vertical ground motion in near field on the dynamic response of LRB infrastructure is analyzed. A more accurate finite element model is established in ABAQUS software: the superstructure adopts fiber model to consider the plastic deformation of isolated structure under near-field earthquake. The isolation layer adopts the "Ryan-Kelly" mechanical model, which can reflect the coupling of horizontal and vertical mechanical properties of the isolation bearing, at the same time, the shear failure and tension compression failure of the isolated bearing are considered synthetically to determine the failure limit of the bearing. The dynamic analysis of isolation structure under the action of horizontal earthquake alone and horizontal vertical earthquake is carried out respectively. The results show that the near field vertical ground motion has a great influence on the failure mode of isolation support. Under the action of large vertical component, the isolated bearing may be subjected to tensile and compressive failure before shear failure. The effect of vertical ground motion on the dynamic response of superstructure is random, but it should not be ignored. The horizontal dynamic response can be greatly reduced by considering vertical seismic action.
【作者单位】：华中科技大学土木工程与力学学院;
【基金】：国家自然科学基金项目(51008134,51178203) 贵州省“十二五”重大科技专项项目(黔科合重大专项[2011]6014)
【分类号】：TU352.12

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