摘要
3/4支撑是指支撑交点位于支撑节间高度h的3/4处的支撑。基于等效水平集中荷载,以顶点位移最小化为设计目标进行拓扑优化得到的3/4支撑,其荷载边界条件与实际工程中常见的跨层支撑有一定区别,设计时需要判断其差异性。层间位移角和顶点位移作为不同设计目标的差异亦不能忽略。对高宽比2~12有限元模型进行参数化分析,结果表明:总体来看,高宽比越大则3/4支撑的抗侧效率越高,有可能超过交叉支撑;随支撑截面加大或柱截面减小,3/4支撑的抗侧效率会逐渐提高;弯曲变形的比例越高,则3/4支撑越有效;3/4支撑角度的突变会导致层刚度的突变和层间位移角不均匀,内筒的存在有助于缓解此问题;3/4支撑的扭转刚度稍差于交叉支撑,对于平面不规则的结构需要关注其差异。
The 3/4 brace refers to the brace where the brace intersection is located at 3/4 of the total height h of the brace. Based on the equivalent horizontal concentrated load, the top point displacement minimization was taken as the design goal to conduct topology optimization to obtain the 3/4 brace, of which the load boundary conditions were different from the common cross-story brace in actual engineering, so the difference needs to be judged during design. The differences between inter-story displacement angles and top point displacements as different design goals could not be ignored. Parametric analysis of the finite element model with a height to width ratio of 2 to 12 shows that in general, the larger the ratio is, the higher the resisting lateral force efficiency of the 3/4 brace is, which may exceed that of the cross brace;as the brace cross section increases or the column cross section decreases, the resisting lateral force efficiency of 3/4 brace will gradually increase;the higher the proportion of bending deformation is, the more effective the 3/4 brace is;the abrupt change of the 3/4 brace angle will cause the abrupt change of the story stiffness and the uneven inter-story displacement angle, and the existence of the inner tube helps to alleviate this problem;the torsional stiffness of the 3/4 brace is slightly worse than that of the cross brace, and it is necessary to pay attention to the difference for the plane irregular structure.
作者
陈寅
陈晓航
黄元根
Chen Yin;Chen Xiaohang;Huang Yuangen(RBS Architectural Engineering Design Associates,Guangzhou 510170,China)
出处
《建筑结构》
CSCD
北大核心
2020年第4期44-48,共5页
Building Structure
关键词
高宽比
3/4支撑
交叉支撑
拓扑优化
结构效率
height to width ratio
3/4 brace
cross brace
topology optimization
structural efficiency
