长沙某超高层环带桁架加强层设计与分析

Design and analysis of ring truss reinforcing layer of a super high-rise building in Changsha

采用环带桁架加强层可以有效的提高整体结构的抗侧刚度。本文以长沙某超高层项目为例,采用周期、刚重比和屈曲因子三个指标衡量结构抗侧刚度,研究了环带桁架不同位置布置、环带桁架截面刚度变化对提高整体结构刚度作用效果的影响,并研究环带桁架截面刚度变化对外框架、核心筒剪力的增大效应的相关性,指出结构整体刚度、外框架总剪力与楼层剪力比、核心筒总剪力与楼层剪力比与环带桁架截面刚度均呈现线性增加—变缓增加—水平不变的三阶段趋势。同时,本文指出,环带桁架布置在塔楼高区对于提升结构刚度效果最为明显。分析了实际项目设置环带桁架后对加强层和上下层的竖向构件的不利影响,并提出相应的解决方案。

The lateral stiffness of the whole structure can be effectively improved by using the ring truss stiffener.Taking a super high-rise project in Changsha as an example,three indexes:period,stiffness-to-weight ratio and buckling factor were used to measure the lateral stiffness of the structure,this paper studied the influence of the position arrangement of the ring truss and the change of the section stiffness of the ring truss on the effect of improving the overall structure stiffness,and studies the correlation of the change of the section stiffness of the ring truss to increase the shear force of the external frame and core tube.It is pointed out that the overall stiffness of the structure,the total shear force ratio of the outer frame to the floor,the total shear force ratio of the core tube to the floor and the section stiffness of the ring truss all show three stages of linear increase,slow increase and constant horizontal trend.At the same time,this paper points out that the ring truss arranged in the high area of the tower has the most obvious effect on improving the rigidity of the structure.analyzes The adverse effect of the ring truss on the vertical members of the reinforcing layer and the upper and lower layers were analysised,and the corresponding solutions were put forward.