带约束拉杆L形截面钢管混凝土的本构关系

分析了带约束拉杆L形截面钢管混凝土在轴压下的受力机理,在确定带约束拉杆L形截面钢管混凝土有效约束区域合理形状的基础上,将带约束拉杆L形截面钢管混凝土短柱划分成一个方形和两个带约束拉杆的矩形钢管混凝土短柱,对截开面的性质和截开面上的边界条件进行合理假设;借鉴约束混凝土的本构关系建立了带约束拉杆L形截面钢管混凝土的等效单轴本构关系,并根据试验数据确定了本构关系中的参数。用建议的本构关系对有关试件进行了荷载-应变全过程分析,荷载-应变的理论计算曲线和试验曲线吻合良好。

CONSTITUTIVE RELATIONSHIP OF L-SECTION CFT WITH BINDING BARS

The interactions within the components of L-section concrete-filled steel tube (CFT) with binding bars subjected to axial load are analyzed. By reasonably setting the effective confined areas of L-section CFT with binding bars, the L-section is divided into a square and two rectangular sections. The rectangular sections have binding bars while the square section has no one. The logical assumptions on the characters and boundary conditions of the cutting section are suggested. The constitutive relationship of confined concrete is adopted to build the equivalent constitutive relationship of the core concrete confined by L-section steel tube with binding bars and the parameters are confirmed through experimental data. The experimental specimens are calculated by the proposed constitutive relationship. The calculating results of load-strain curves are in good agreement with the experimental ones.