多腔钢管混凝土柱巨型框架抗震性能试验研究

Experimental Research on Seismic Behavior of Mega-Frame with Multi-Cell CFST Columns

结合某超高层巨型框架结构工程实际,进行了一榀巨型框架结构底部三个巨型层1/25缩尺模型抗震性能试验研究。该巨型框架的巨型柱为多腔钢管混凝土异形截面柱,巨型梁为钢桁架梁,底部巨型层加设人字形箱形截面钢支撑,二、三巨型层加设X形箱形截面钢支撑。通过试验,分析了该巨型框架的滞回特性、承载力、刚度及退化过程、延性和屈服机制。试验表明,该巨型框架的支撑作为第一道防线首先屈服,之后巨型桁架梁上下弦杆进入屈服,最后巨型柱柱底出现塑性铰,实现了多腔钢管混凝土柱巨型框架结构延性屈服机制,抗震性能良好。

The experimental research on seismic behavior of a 1/25 scaled mega-frame model with 3 mega- storey from the bottom has been carried out according to a supper high-rise mega-frame structure building. The multi-cell special-shaped CFST columns are used for mega-columns. The steel truss beams are used for mega- beams. The K-shaped steel brace with box section is set at the bottom mega-storey. The X-shaped steel braces with box section are set at the second and the third mega-storey. The hysteretic properties, load-bearing ca- pacity, stiffness and its degeneration, ductility and yielding mechanism of the mega-frame have been analyzed based on the experiment. The results show that the brace in the mega-frame yields as the first line of defense. Then the upper and the lower chord members of mega truss beam yield. At last, the plastic hinges appear at the bottom of mega-column. The ductile yielding mechanism has been achieved for the multi-frame structure with multi-cell CFST columns with good seismic behavior.