摘要
采用CEB-FIP(1990)规范中的混凝土收缩徐变模型,考虑含钢率、套箍效应对混凝土收缩徐变的影响,计算了某超高层巨型混合结构竖向构件的竖向变形,分析弹性模量发展对竖向构件变形的影响,并研究竖向变形差对关键构件的内力影响。为实现在设定阶段竖向构件达到设计标高,对楼层标高预留高度和竖向构件下料预留长度的控制方法进行了研究。进一步提出减小竖向构件竖向变形差的措施,并通过算例验证了其有效性。研究表明,混凝土弹性模量发展对竖向构件变形影响不大;而混凝土的收缩徐变对超高层混合结构的变形及内力影响较大,应以考虑了混凝土收缩徐变的结构模型作为地震分析的初始态对关键构件进行校核;在带钢管混凝土柱的超高层巨型混合结构中,控制钢管混凝土柱压应力水平适当大于钢筋混凝土核心筒的压应力水平,可有效降低混凝土收缩徐变引起的竖向变形差及附加内力。
Using the concrete shrinkage and creep model in CEB-FIP(1990)specification,considering the influence of steel content and hoop effect on concrete shrinkage and creep,the vertical deformation of a super high-rise mega hybrid structure vertical components was calculated,and the influence of elastic modulus development on the deformation of vertical components was analyzed,and the influence of vertical deformation difference on the internal forces of key components was studied.In order to achieve the design elevation of the vertical components in the set phase,the control method of the reserved height of the floor elevation and the reserved length of the vertical component blanking was studied.Further measures to reduce the vertical deformation difference of vertical components were proposed,and the effectiveness was verified by an example.The research shows that the development of concrete elastic modulus has little effect on the deformation of vertical components.However,the shrinkage and creep of concrete have great influence on the deformation and internal forces of super high-rise hybrid structures.The structural model considering concrete shrinkage and creep should be used as the initial state of seismic analysis to check the key components.In the super high-rise mega hybrid structure with concrete filled steel tube column,the compressive stress of concrete filled steel tube column is controlled to be larger than that of reinforced concrete corewall,which can effectively reduce the vertical deformation difference and additional internal force caused by concrete shrinkage and creep.
作者
赵建
周定松
周佳
肖克艰
冯中伟
张恒飞
Zhao Jian;Zhou Dingsong;Zhou Jia;Xiao Kejian;Feng Zhongwei;Zhang Hengfei(China Southwest Architectural Design&Research Institute Corp.,Ltd.,Chengdu 610041,China)
出处
《建筑结构》
CSCD
北大核心
2020年第1期44-51,共8页
Building Structure
关键词
超高层巨型混合结构
收缩徐变
竖向变形差
楼层预留高度
竖向构件下料预留长度
压应力水平
super high-rise mega hybrid structure
shrinkage and creep
vertical deformation difference
reserved height of floor
reserved length of vertical component blanking
compressive stress level
