跨越地裂缝复杂连体结构动力响应分析

Dynamic response analysis of complex connected structures crossing ground fissures

为研究地震作用下跨地裂缝复杂连体结构的动力响应,本文基于地裂缝的三维位移活动特征,将地裂缝蠕动变形量以初始位移形式施加在分析模型上,同时施加罕遇地震,分析地裂缝活动对上部结构在地震作用下的影响,重点考察了结构关键构件内力变化,结构的层间位移角,层间剪力等指标。分析表明:地裂缝沉降量的增加对上部结构的不利作用也随之增大,考虑罕遇地震下50年地裂缝活动发展,结构关键杆件的内力变化在10%~20%左右,个别杆件增幅较大,建议增大截面。结构的层间位移角最大为1/118,整体侧移值较小,满足规范限值要求,说明选取的支座连接形式能有效减弱地裂缝沉降对结构的影响。

To study the dynamic response of complex connected structure crossing the ground fissures under the earthquake,the creep deformation of ground fissures is applied to the analysis model in the form of initial displacement in this paper,which is based on the three dimensional displacement characteristics of ground fissures.At the same time,to analyze the influence of ground fissure activity on the structure under the earthquake in detail,the rare earthquake effect is considered in the modeling possess.Besides,the internal force change of the key components of the structure,the story drift angle of the structure,and the story shear force are mainly investigated.The analysis shows that the adverse effect on the structure develops rapidly with an increase in the subsidence of ground fissures.In addition,the development of the ground fissures activity in 50 years under the rare earthquake is considered,the internal force of the key members of the structure is changed by about 10%~20%,and the increase of individual members is large.Analysis indicates that the increase of the section is advisable.Moreover,the maximum story drift angle of the structure is 1/118,and the overall lateral displacement value is small,which meets the requirements of the code limit.Results demonstrate that the selection of bearing connection form in this work can effectively reduce the impact of subsidence of ground fissures on the structure.