摘要
钢框架-中心支撑结构(Steel Concentrically Braced Frame,简称CBF)是钢结构领域一种典型的双重抗侧力体系,由于该结构具有较大的初始抗侧刚度,支撑失效后框架部分仍能够提供强度和刚度,实际工程中得到了广泛应用。本文以单自由度钢框架-支撑体系为基础,定义了反映框架和支撑间刚度与强度比例关系的两个基本参数,按照我国现行抗震规范选取了20条不同场地的地震记录,基于延性运动方程对CBF体系进行了延性时程反应分析,建立了地震作用下单自由度CBF体系延性需求谱,分析过程中考虑了重力二阶效应和场地效应的影响。最终,依据结构延性能力和延性需求谱确定了基本参数的取值范围和CBF体系的临界周期,为此类结构的抗震设计提供重要参考。
Steel concentrically braced frame is a typical kind of dual system in steel structure.It is widely used for its large initial lateral stiffness,and the secondary strength and stiffness after braces fracture plays an important role in seismic collapse prevention.In this paper,SDOF systems are employed to represent CBFs system,and two parameters that relate the reserve system to the primary system are put forward.Time history analyses are carried out by 20 ground motion records from different sites based on the ductility governing equation of motion.The ductility demand spectra are presented and the influence of P-Δ effect and site effect are taken into account.Finally,the threshold periods and the parameter values of CBF systems are explored and identified on the basis of ductility demand spectra and structural ductility demand.The conclusion can provide references to the design of the CBF system.
出处
《地震工程与工程振动》
CSCD
北大核心
2014年第3期84-94,共11页
Earthquake Engineering and Engineering Dynamics
基金
新世纪优秀人才支持计划项目(NCET-13-0074)
中央高校基本科研业务费专项资金项目(DUT13ZD203)
