高层建筑结构推覆分析及对设计的启示

本文作者及其研究小组在过去的几年中对混凝土高层结构进行了推覆分析的研究,并编制了相应的计算机程序(TBPOA)。为了满足复杂体型高层结构的需要,提出了多种类型的单元,包括梁柱单元、单片墙单元、三垂直杆墙元和筒体墙单元,与试验结果对比分析表明这些模型具有很好的精度,并且能够搜索到结构反应的全过程,甚至结构的软化阶段。3个实际工程的推覆分析结果表明:小震作用下弹性分析所得的结果并不能反映结构可能存在的薄弱部位,罕遇地震作用下的弹塑性变形应该考虑结构二阶效应的影响,抗震规范提供的抗震设计原则和构造要求在某些结构中并不能保证罕遇地震下的抗震性能,对复杂高层结构进行推覆分析或弹塑性时程分析是很有必要的。

Push-over analysis of high-rise buildings and its influence on structural design

In the past years,the study of push-over analysis and corresponding computer program(TBPOA) were carried out by the authors and their research group.Several kinds of elements in the program are considered to satisfy the need of high-rise buildings with complex structural type.These elements include beam-column element,single slice wall element,three vertical line element for walls and tube-wall element for tubes.In comparison with test results, it is showed that these models possess high precision.TBPOA can search for the full process of structural response,even the softening stage of the structure.Push-over analyses for three actual high-rise structures showed that the results of elastic analysis under frequently occurred earthquake cannot reflect the probably existed weak floors of the structure,the elastic-plastic analysis of deformation under rarely occurred earthquake has to consider the second-order effect,in some structures,the seismic design criteria and constructional requirements provided by seismic codes cannot guarantee the seismic performances under rarely occurred earthquake.Push-over or nonlinear time-history analysis for high-rise structures with complex type is quite necessary.