摘要
在中国规范体系下,框架-核心筒结构应设计为双重抗侧力体系,其对二道防线的设计有明确的规定,即框架-核心筒体系的框架部分必须具有足够的抗侧刚度和承载力。国外的一些规范(如美国规范ASCE7等)则允许单重抗侧力体系,即水平荷载由剪力墙承担,框架部分只承担竖向荷载。因此,为了比较单重与双重抗侧力体系的抗震性能,该文首先根据中国规范设计一典型框架-核心筒双重抗侧力体系模型,然后在保持结构重力荷载代表值相等(混凝土用量基本不变)的前提下,基于以下调整原则设计了框架-核心筒单重抗侧力体系模型:1)在双重结构体系的基础上取消结构二道防线,即取消结构框架部分的楼层剪力调整;2)为了减小框架构件截面尺寸,该研究取消了框架构件抗震等级的要求,使筒体承受大部分的水平地震作用,而框架只承担结构的竖向荷载。该文对比分析了两种结构体系在多遇和罕遇地震作用下的响应特征和构件损伤情况,进而讨论两种体系的倒塌机理以及抗倒塌性能。最后讨论单重与双重体系在不同地震水准下,框架所承担剪力和剪力分担比的变化情况以及对应关键构件的破坏情况。研究表明:在地震作用下,双重抗侧力体系结构的响应略大于单重抗侧力体系,两者的抗倒塌能力相当。然而,单重体系的用钢量比双重体系少。
In the design code system of China,frame-core tube structure should be designed as a dual lateral-force resisting system,and there are strict requirements for the secondary lateral-force resisting system of such structure.In other words,the outer frame of the frame-core tube structure should have sufficient lateral stiffness and strength.However,in the design codes of other countries(e.g.,ASCE-7 of the United States),the outer frame of the frame-core tube structure is permitted to only carry the vertical load.Therefore,to compare the seismic performances of the single and dual lateral-force resisting systems of the frame-core tube structure,a dual lateral-force resisting system model was firstly designed following the design codes of China.Subsequently,under the same gravity load(and the same concrete consumption),the single lateral-force resisting system model of the frame-core tube structure was design according to the following procedures:1)the secondary lateral-force resisting system was removed from the dual system,and the shear force adjustment of the frame was ignored;2)the seismic detailing requirement of the frame was lowered to reduce the sectional size.As a result,the tube beared most of the seismic load,and the frame only resisted the vertical load.The structural responses and component damage of these two systems under SLE(Service Level Earthquake)and MCE(Maximal considered earthquake)were analyzed.Furthermore,the collapse mechanisms of two structures and their collapse-resistances were investigated.Finally,the variation of the shear force and shear distribution of the frame under different levels of earthquake and the corresponding damage of key components were discussed.The research shows that the response of the dual system structure was slightly greater than that of the single system,and their collapse resistant capacities were similar.However,the steel consumption of the single system was less than that of the dual system.
作者
谢昭波
解琳琳
林元庆
陆新征
CHEA Cheav Por;XIE Lin-lin;LIN Yuan-qing;LU Xin-zheng(Beijing Engineering Research Center of Steel and Concrete Composite Structures,Tsinghua University,Beijing 100084,China;School of Civil and Transportation Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044,China;China Nuclear Power Engineering Co.,Ltd.,Zhengzhou Branch,Zhengzhou,Henan 450052,China;Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry,Department of Civil Engineering,Tsinghua University,Beijing 100084,China)
出处
《工程力学》
EI
CSCD
北大核心
2019年第10期40-49,共10页
Engineering Mechanics
基金
国家自然科学基金项目(51778341)
关键词
框架-核心筒结构
高层结构
抗侧力体系
抗震性能
剪力分担比
frame-core tube structure
tall building
lateral-force resisting system
seismic performance
shear distribution
