轴压下带约束拉杆L形钢管混凝土短柱的试验研究

对7根轴压下L形钢管混凝土短柱(6根带约束拉杆,1根无约束拉杆)进行试验,介绍试件和试验方案的设计,分析钢板厚度、约束拉杆的直径和水平间距等主要参数对带约束拉杆L形钢管混凝土短柱极限承载力和延性的影响.试验表明,在L形钢管混凝土短柱上设置约束拉杆,可以有效地延缓钢管壁的局部屈曲,改善钢板对核心混凝土的约束效应,提高该类构件的极限承载力和延性.最后,将带约束拉杆L形钢管混凝土短柱划分成1个方形和2个带约束拉杆的矩形钢管混凝土短柱,并借鉴带约束拉杆方形钢管混凝土承载力的计算公式,对带约束拉杆L形钢管混凝土短柱的极限承载力计算方法作初步探讨.

Experimental investigation on L-shaped concrete-filled steel tube stub columns with binding bars under axial load

Seven L-shaped concrete-filled steel tube stub columns, including six specimens with binding bars and one specimen without for comparison, were tested. The experimental program and parameters for specimens are introduced particularly. The effects of thickness of tube, diameter and level spacing of the binding bars on the ultimate strength and ductility of the specimens are analyzed. The experimental results show that binding bars can postpone the local buckling of the tube, improve the confining effect of the tube to core concrete, and enhance the ultimate strength and ductility of this type of members. Based on the ultimate strength equations of concrete-filled square steel tube stub columns with binding bars, a method to calculate the ultimate strength of L-shaped concrete-filled steel tube stub columns with biding bars is proposed, in which the L-section is divided into one square section without binding bars and two rectangular sections with binding bars.