摘要
以上部结构分别为三层、五层、七层和九层的LRB(铅芯橡胶隔震支座)基础隔震结构为研究对象,考虑了上部结构屈服强度比、刚度、硬化系数等的影响,通过大量的弹塑性时程分析,对极罕遇地震作用下隔震结构无碰撞以及隔震层与限位墙发生碰撞时的非线性响应特性进行了分析和对比。结果表明:增大上部结构屈服强度比,可以有效降低上部结构的层间位移和延性需求;当屈服强度比越小、上部结构刚度越大时,硬化系数对结构响应的影响越大;无碰撞时,对于上部结构基本自振周期在一定范围内变化的LRB基础隔震结构,相同的屈服强度比对应的上部结构延性需求、损伤状态基本一致,但是当隔震层与限位墙发生碰撞,上部结构破坏程度会有很大差异,特别是上部结构刚度较大时,延性需求增大非常明显,这种情况下上部结构破坏已经非常严重甚至会倒塌。
The LRB(lead-core rubber isolation support)base-isolated structures with three,five,sev⁃en and nine-story superstructure were taken as research object.The influence of yield strength ratio,stiffness and hardening coefficient of the superstructure was considered.Through a large number of elastoplastic time history analysis,the nonlinear response characteristics of LRB base-isolated struc⁃tures without collision or impacting with the moat wall under extremely rare earthquakes were ob⁃tained.The results show that increasing the yield strength ratio can effectively reduce the inter-storey displacement and ductility demand of the superstructure.When the yield strength ratio is smaller and the stiffness of the superstructure is larger,the effect of the hardening coefficient on the structural re⁃sponse is greater.When there is no collision,for the LRB base-isolated structures whose self-vibration period of the superstructure changes within a certain range,the ductility demand and the damage state remain unchanged under the determined yield strength ratio..However,when the LRB layer impacts with the moat wall,the superstructure damage will be very different.Especially,if the superstructure stiffness is large,the ductility demand increases very obviously.In such a case,the superstructure damage has been very serious or even leads to collapse.
作者
黄潇
胡志祥
刘运林
HUANG Xiao;HU Zhixiang;LIU Yunlin(School of Civil Engineering,AnHui JianZhu University,Hefei 230601,China;School of Civil and Hydraulic Engineering,Hefei University of Technology,Hefei 230009,China)
出处
《防灾减灾工程学报》
CSCD
北大核心
2022年第3期436-444,共9页
Journal of Disaster Prevention and Mitigation Engineering
基金
安徽省高校省级自然科学研究项目⁃重点项目(KJ2020A0451)
安徽建筑大学科研基金(2019QDZ51)
安徽省自然科学基金(1908085ME144)
中央高校基本科研业务费专项(JZ2021HGTB0103)资助。
关键词
基础隔震结构
橡胶隔震支座
极罕遇地震
碰撞
延性需求
base-isolated structure
lead-core rubber isolation support
extremely rare earthquake
im⁃pact
ductility demand
