扭曲体型高层网筒结构体系的结构布置及基本性能

为配合扭曲体型高层建筑方案,提出扭曲体型高层网筒结构体系,给出其结构布置,分析扭曲程度对结构基本性能的影响。通过系列模型计算,探讨了旋转角、主环梁层间距、结构高宽比等几何参数对结构抗侧性能的影响。其中,旋转角和结构高宽比是主要影响参数,主环梁层间距影响不大。扭曲结构最大抗侧刚度对应的层旋转角存在一个适宜区间,随着高宽比的增大,此角度区间范围变窄;在此区间内扭曲体型能够有效提高抗侧刚度,在此区间之外其抗侧性能则比传统非扭曲结构差。当结构总旋转角为90°时,不同高宽比的扭曲结构都具有最优抗侧性能。扭曲结构虽然受力合理,但是从底部算起至少半数楼层的主环梁必须考虑竖向荷载产生的轴拉力,而且考虑主环梁轴拉力的楼层数占总层数的比例随着高宽比的增大而增大。扭曲体型高层网筒结构体系具有良好的结构效率和抗侧性能。

Structural arrangements and performance of high-rise twisted diagrid tube structures

For the sake of architectural design of twisted high-rise buildings,twisted diagrid tubular structures were developed along with the general structural arrangements with effects of twist on structural performance being analyzed.A series of structural model analyses were carried out to evaluate the influence of some geometric parameters on the lateral resistance.The results show that the rotation angle and height-to-width aspect ratio are dominant,while the storey interval between two adjacent main ring beams is insignificant.There exists a suitable range of storey rotation angles resulting in the maximum lateral stiffness,which narrow with increasing aspect ratio.In terms of the lateral stiffness,the twisted structure is superior within,but inferior out of this range of storey rotation angles,compared with the conventional non-twisted ones.When the accumulative rotation angle at the top reaches 90°,the optimal lateral resistance can be achieved for the structures with different aspect ratios.Twisted diagrid tubular structures have better structural performance,however,axial forces of main ring beams under vertical loadings have to be considered for over half stories upward from the base,particularly for large aspect ratios.Twisted diagrid tubular structures are proved to have better structural efficiency and remarkably hence the lateral resistance.