【摘要】 为使钢管混凝土叠合柱-混凝土梁节点能得到广泛应用,提出一种新型钢管混凝土叠合柱-混凝土梁的连接节点,利用设置于叠合柱中钢管外的环筋平衡混凝土框架梁端纵筋的拉力,梁端纵筋以卡扣、弯折等形式与柱中环筋连接。制作6个边节点试件,进行梁受弯单调加载试验,考察节点试件的裂缝发展及分布、变形、破坏形态、承载力以及延性,揭示梁纵筋锚固构造的传力机制。试验结果表明,试件的裂缝集中于梁根部的塑性铰区,表现为弯曲破坏形态,有充分的塑性变形能力,延性系数大于普通钢筋混凝土柱-梁节点的延性系数;梁根部受拉侧纵筋均能在柱中环筋屈服前以及试件达到峰值荷载前屈服;试验过程中未出现梁纵筋和柱中环筋应变突变现象。梁纵筋与柱中环筋的3种连接构造形式具有类似的受力性能,均锚固可靠。利用ABAQUS程序对试验过程进行仿真模拟分析,计算结果与试验结果吻合。更多还原

【Abstract】 A new type of joint between concrete-encased concrete-filled steel tubular(CFST) columns and concrete beam was proposed to make wide use of the joint of concrete-filled steel tubular composite column-concrete beam. The tensile force of longitudinal reinforcement at the beam end of the concrete frame was balanced by the ring reinforcement outside the steel tube in the composite column.The longitudinal reinforcement at the beam end was connected with the ring reinforcement in the column in the form of buckle, bending and so on. Six side joints were made and tested under bending monotonic load in order to test the distribution and development of cracks, deformation, failure mode, bearing capacity and ductility of the side joints. And the force transfer mechanism of the anchorage structure of longitudinal reinforcement was revealed. The test results show that, the cracks of the specimens are concentrated in the plastic hinge area at the end of the beam and shows a bending failure mode with sufficient plastic deformation capacity; the ductility coefficient is greater than that of the ordinary reinforced concrete column beam joint; the longitudinal reinforcement at the tensile side of the beam end can yield before the ring bars yield in the column and the specimen reaches the peak load; there is no strain mutation in the longitudinal reinforcement of beam and ring reinforcement of column in the test. The results show that the three connection forms of longitudinal reinforcement and ring reinforcement have similar mechanical performance, and they are all anchored reliably. The test process was simulated by ABAQUS program, which proved the consistence between the calculated results and the test results.更多还原