摘要
结构地震响应与所在场地的土层条件密切相关,而水平双向地震动作用方向的差异也会导致结构不同方向震害的差异.基于设计反应谱,选取了20组实际记录的水平双向地震动,针对基岩(Ⅰ_(0))、Ⅱ类以及Ⅲ类场地,对五层钢筋混凝土框架结构在双向地震动作用以及场地土层非线性效应共同影响下的地震响应进行分析,研究场地效应对地表地震动方向性以及上部结构地震响应方向性的影响.研究表明:在结构抗震设计时,不仅要考虑场地效应引起的地表地震动放大,还需要考虑场地效应引起结构地震响应的最不利方向以及方向差异性相比于基岩地震动作用时的变化;仅考虑出露基岩地震动输入的结构地震响应分析往往不安全,且忽略了场地效应对结构地震响应最不利方向的影响.
The seismic response of the structure is closely related to the soil layer conditions of the site,and the difference in the input direction of horizontal bi-directional ground motion will also lead to the difference in the seismic damage of the structure in different directions.Based on the design response spectra,20 sets of actual recorded horizontal bidirectional ground motions are selected as the seismic input.Seismic response analyses for the five-story reinforced concrete frame structure on the bedrock(Ⅰ_(0)),ClassⅡandⅢsites are performed.The influence of nonlinear effect of site soil layer and the bidirectional ground motion on the directionality of seismic response of structure is investigated.The results show that in the seismic design of the structure,not only the amplification of surface ground motion caused by site effect should be considered,but also the most unfavorable direction of the structural seismic response caused by the site effect and the change of direction difference compared with bedrock ground motion should be considered.The structural seismic response analysis considering only the ground motion input of the outcrop bedrock is often unsafe,and the influence of site effect on the most unfavorable direction of structural seismic response is ignored.
作者
宋健
亓富丽
张子阳
吴凯莉
SONG Jian;QI Fuli;ZHANG Ziyang;WU Kaili(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210024,China;College of Civil and Transportation Engineering,Hohai University,Nanjing 210024,China;Lille College,Hohai University,Nanjing 210024,China)
出处
《河南科学》
2023年第11期1628-1637,共10页
Henan Science
基金
国家自然科学基金面上项目(52178325)。
关键词
土层非线性
场地效应
结构地震响应
最不利方向
方向差异性
soil layer nonlinearity
site effect
structural seismic response
the most unfavorable direction
directional difference
