为了研究分离式竖向加劲板钢管混凝土柱-梁节点的抗震性能,对7个节点试件进行了在柱顶施加恒定轴压力、梁端施加往复荷载的试验。通过对试验数据分析,得到了各个试件的荷载-位移曲线、骨架曲线、应变曲线、强度和刚度退化规律、延性等结果。试验观测到节点发生3种破坏模式:梁翼缘在加劲板短边附近受拉破坏;梁翼缘和加劲板间焊缝受剪破坏;与加劲板连接处的钢管壁受拉破坏。在屈服线理论的基础上,提出了与加劲板连接处钢管壁受拉破坏模式下的塑性机构模型。根据虚功原理推导出了该模式下的屈服荷载计算公式,计算公式与试验结果吻合较好。将推导出的公式与典型的3种破坏模式计算公式相组合,可以准确地预测节点最终破坏模式。
In order to study the seismic performance of CFT column-to-beam joints with detached vertical stiffeners, 7 joint specimens were tested under constant axial compression at the top of the column and cyclic loads at
the end of the beam. Through the analysis of test data, the load-displacement curve, skeleton curve, strain
curve, strength and stiffness degradation laws, ductility and other results of each specimen were obtained. Three
ultimate failure modes of the joints were found in the tests, namely, tensile failure of the beam flange near the
short edge of vertical stiffeners, shear failure of welds between the beam flange and vertical stiffeners, and tensile
failure of the steel tube wall connected with vertical stiffeners. Then a plastic mechanism model of the joints under
tension failure mode of the steel tube wall connected with vertical stiffeners was put forward based on the yield-line
theory. And the yield load calculation formula under this mode was derived according to the principle of virtual
work. The calculated results are in consistent with the test results. Combining the derived formula with calculation
formulas of three typical failure modes, the ultimate failure mode of the joints can be accurately predicted.