不同巨型支撑设置对中国建筑千米级摩天大楼的影响

Impact of different arranged location of mega bracings on 1000m-high skyscraper of CSCEC

以高1 180m的中国建筑千米级摩天大楼为载体,在3个周边单塔+中央交通核每100m通过2层连接平台刚性连接而成巨型组合结构体的3个单塔上设置5种不同的巨型支撑布置方案,同时也考虑了在连接平台桁架上设置不同斜撑方式的影响,来研究巨型支撑对结构刚度、刚重比、周期、楼层剪力、位移及框架承担剪力占基底剪力百分比等结构设计控制指标的影响。研究结果表明:连接平台桁架上下设置X形斜撑对结构提供的刚度明显大于人字形斜撑;巨型支撑可显著提高结构的整体刚度,增大结构的刚重比,减小结构的周期和楼层位移角;巨型支撑对结构的刚度比、楼层剪力影响不大;巨型支撑可显著增大外框承担的剪力,增强外框架的刚度,提高框架承担基底剪力的百分比。

The 1 000m-high out-of-code high-rise building skyscraper has height of 1 180 m and it consists of 3 main surrounding towers and one central traffic tower which are rigidly connected by two stories 15m-high connected platform in every 100 m. Considering impact of different bracing arrangements on trusses on connected platforms,five different types of mega bracing schemes were set on the 3 surrounding towers,to study the influence of mega bracing on structural design controlling parameters including structural rigidity,rigidity-to-gravity ratio,period,story shear forces,displacements,ratio of shear force carried by frames to total base shear force. The study results indicate that X-shaped bracing contributes a much larger stiffness than V-shaped bracing. Mega bracing can significantly increase the overall stiffness of the structure,resulting in an increase in rigidity-to-gravity ratio,and a decrease in structural period and inter-story displacements. Mega bracings have little influence on structural stiffness ratio and inter-story shear forces. Mega bracing can significantly increase the shear force carried by exterior frames,enhance stiffness of the exterior frames,and increase the ratio of shear force carried by frames to total base shear force.