竖向荷载作用下柱列支撑体系受力性能试验研究及有限元分析

Experimental investigation and finite element analysis on mechanical behavior of column-bracing system under vertical loading

为研究柱列支撑体系的受力性能和验证有限元方法分析该问题的可靠性,对带有不同初始几何缺陷分布的单层和双层柱列支撑体系进行静力模型试验研究。研究结果表明:由于试验模型中柱和水平撑杆的初始几何缺陷的随机分布,水平撑杆受压力或拉力也是随机的;双层柱列支撑体系的极限承载力高于单层柱列支撑体系的极限承载力,且双层柱列支撑体系中的水平撑杆减小柱的计算长度超过柱高的一半;柱列支撑体系的失稳破坏是由于单柱失稳破坏引发的。采用有限元模型对试验进行了模拟验证,计算结果与试验结果吻合良好。

In order to investigate the mechanical behavior of column-bracing system and verify the reliability of finite element analysis, the static experimental studies were conducted on one-story and two-story column-braclng systems with different distributions of the initial imperfections. It is found that the horizontal inter-column brace forces in compression or in tension have also randomness because of the randomness of the initial imperfections of both the columns and braces. The ultimate load-carrying capacity of two-story column-bracing systems is higher than that of one-story column-bracing systems because the mid-height horizontal braces of two-story column-bracing systems can reduce the effective column length more than half of column length. Buckling failure of column-bracing systems is caused by buckling failure of a column. Moreover, a finite element model is developed and verified against tests, and the results from the finite element analysis agree well with the experimental data.