不均匀竖向荷载作用下弯曲型高层建筑的整体稳定验算  

Overall stability checking of flexural tall buildings under uneven vertical loads

作　　者：黄吉锋[1] 徐培福[1] 陈富盛 Huang Jifeng;Xu Peifu;Chen Fusheng(China Academy of Building Research,Beijing 100013,China)

机构地区：[1]中国建筑科学研究院

出　　处：《建筑结构》2018年第24期53-57,84,共6页Building Structure

摘　　要：整体稳定控制是高层建筑结构设计中的重要问题之一。《高层建筑混凝土结构技术规程》(JGJ3—2010)通过刚重比来控制结构整体稳定和二阶效应幅度,其刚重比公式适用于竖向荷载沿高度分布相对均匀的结构。高规适用高度范围内,绝大部分弯曲型高层建筑的竖向荷载沿高度分布是相对均匀的,近年来我国高层建筑迅速发展,有些超高层建筑出现竖向荷载从下到上显著变小甚至突变的情况,直接用高规刚重比公式计算过于保守、存在较大误差。针对竖向荷载不均匀的弯曲型结构,探讨并提出了适用的刚重比公式,此刚重比公式可以合理反映竖向荷载不均匀对刚重比的影响,同时在竖向荷载均布情况下直接退化为高规的刚重比公式。理论和算例分析表明,建议的刚重比公式计算精度可以满足工程需要,且在各种竖向荷载模式下均偏于安全,具有工程实用价值。Overall stability control is one of the important issues in the structural design of tall buildings.Technical specification for concrete structures of tall building (JGJ 3-2010)(specification for short)stipulates to control the structural overall stability and the second-order effect amplitude by the stiffness-weight ratio.Its stiffness-weight ratio formula is applicable to struetures with relatively uniform vertical load distribution.Within the applicable building height range of the specification,the vertical load distribution along the height of most flexural tall buildings is relatively uniform. Meanwhile,China's tall buildings have developed rapidly in recent years,and vertical loads are significantly,smaller or even abrupt from bottom to top in some super-tall buildings.It is too conservative and there is a large error if the stiffness-weight ratio formula in the specification was directly used.Aiming at the tall building structure with uneven vertical load,the applicable formula was proposed to calculate stiffness-weight ratio.The stiffness-weight ratio formula could reasonably reflect the influence of the vertical load unevenness on the stiffness-weight ratio,and it directly degenerated into the stiffness-weight ratio formula of the specification in the case of uniform vertical load.The analysis on theoretical and numerical examples shows that the calculation accuracy of the proposed stiffness-weight ratio formula can meet the engineering needs,and it is safe in all kinds of vertical load modes,and has engineering practical value.

关 键 词：高层建筑 结构稳定 刚重比 临界屈曲荷载因子 

分 类 号：TU318[建筑科学—结构工程]