带加强层框架-核心筒结构中单伸臂桁架刚度比的合理取值

Rational stiffness of single outrigger trusses in frame-core structure with outriggers

推导带加强层框架-核心筒结构顶层位移的简化计算公式,提取影响结构顶层位移的刚度比特征参数:伸臂弯曲刚度比i、伸臂剪切刚度比g、外框架柱弯曲刚度比p。采用ETABS软件建立一253.2 m超高层结构模型,研究水平均布荷载和地震作用下结构的侧移、内力与i、g、p的相互关系。研究结果表明,采用刚度比特征参数i、g、p对结构侧向刚度进行优化是合理可行的,p对结构侧向刚度影响最大,其次是g,最小是i,其中i的取值不宜超过0.6,g的取值宜控制在0.9～3.5区段之间,p的取值宜控制在1.3～4.6区段之间。

The characteristic parameters of bending stiffness ratio i,shearing stiffness ratio g of outrigger trusses and bending stiffness ratio p of column were investigated in order to get the simplified calculation formula of structural roof displacement in frame-core structure with outriggers.The relationships among the structural roof displacement,internal forces and i,g,p under uniformly distributed loading and earthquake loading were studied taking as example a 253.2-meter super-rise building using the software ETABS.The results show that i,g,p adopted for optimizing the structural lateral stiffness are reasonable and feasible,and p has the greatest influence on the structural lateral stiffness,the second is g and i has the smallest effect.As for the characteristic parameters,i should not be bigger than 0.6,g should be between 0.9~3.5,and p should be between 1.3~4.6.