某竖向混合结构的弹塑性时程分析

Elasto-plastic Time History Analysis of a Vertial Hybrid Structure

由两种或两种以上不同材料串联组成的结构称为竖向混合结构[1]。由于其在建筑和结构上的优势,该结构体系已在国内重大工程中得到应用。但其竖向刚度的变化,使得竖向混合结构的地震反应比一般非混合结构复杂。针对某一竖向混合结构,采用有限元分析软件PERFORM-3D,在6度(0.05 g)罕遇地震作用下进行弹塑性时程计算,并分析该结构的变形、耗能、顶部鞭梢效应和破坏模式,评价其抗震性能。结果表明:在6度罕遇地震作用下,结构体系变化的楼层处,层间位移角发生明显变化,此处柱容易屈服;顶部钢结构部分未产生明显鞭梢效应;该结构耗能合理,满足"大震不倒"的设计要求。

The vertical hybrid structure is the structure with upper steel and lower concrete components （S/ RC structure）. Because of its advantages in architectures and structures, it has been used in critical engineering projects in China. However, the changes of the vertical stiffness of S/RC structure make the building performance more complex than the ordinary structures when subjected to seismic load. In this paper, in order to study the seismic behavior of a structure located in 6 seismic intensity （0.05 g） area , PERFORM- 3D was used to perform elasto-plastic time history analysis. Besides, this paper analyses the deformation, dissipation ,whipping effect and failure mode, and evaluate its seismic behavior. The calculation results indicate that the inter story drift becomes dramatically at the floors where vertical stiffness changes and it is rational in the dissipation and can meet the requirement of the 3-level design.