冷弯薄壁方钢管混凝土梁的荷载-位移滞回性能研究

Research on the load-displacement hysteretic behavior of concrete-filled thin-walled cold-formed square steel beam

进行6根冷弯薄壁方钢管混凝土简支梁在循环荷载作用下的试验,研究了试件的破坏形态,并对其荷载-位移滞回关系曲线及其骨架曲线进行分析,研究其在不同参数下的滞回性能、延性等重要抗震性能指标.得到的主要结论如下:⑴冷弯薄壁方钢管混凝土简支梁荷载-位移滞回曲线呈梭形,较为饱满,没有出现明显的捏缩现象,表明构件具有较好的延性和耗能能力.⑵宽厚比越小,滞回曲线梭形越饱满;跨高比越小,滞回曲线梭形也越饱满,构件的塑性变形能力越强,具备更好的地震吸收能力和优越的抗震能力.⑶比较荷载-位移滞回曲线的骨架曲线,不同参数对冷弯薄壁方钢管混凝土梁的竖向承载力影响很大.

Six concrete-filled thin-wailed cold-formed square steel tubes beams in cyclically loading were test- ed. The author researched the failure mode, analysed the load-displacement hysteretic curves and its frame- works curves through the experiment. Some different parameters of earthquake resistant capability can be re- viewed ,such as hysteretic behavior and ductility. Some important conclusions can be drew as follows： （1）The shape of load-displacement hysteretic curves of concrete-filled thin-walled cold-formed square steel tubes beams like a spindle.It is of satiation without obvious phenomenon of rheostriction. The members accordingly have good capacity of ductility and energy dissipation. （2）If the width-thickness ratio is smaller or the span- height ratio is smaller, the plumper of the load-displacement hysteretic curves spindle shape is well, and it shows the better capacity of plasticity , then it is provided that it has better properties of resisting the seism.（3） The different parameters have great influence on the vertical beating capacity of concrete-filled thin-walled cold-formed square steel tubes beams after analysed its framework curve of load-displacement hysteretic curve.