摘要
为研究钢筋混凝土(RC)板对复式钢管混凝土(CFDST)柱-钢梁上焊下栓节点抗震性能的影响,开展了5个组合节点的低周往复荷载试验,分析了有无RC板、下环板螺栓数量、RC板厚度和宽度对节点破坏形态、滞回曲线、承载能力、延性、刚度退化、耗能能力以及钢梁腹板应变的影响。结果表明:节点破坏形态表现为钢梁上翼缘与上环板连接处断裂或屈曲变形、钢梁下翼缘与下环板螺栓连接处水平滑移以及RC板混凝土破碎剥离等;节点的滞回曲线形状饱满、无捏缩;转角延性系数介于3.04~4.60之间;RC板的设置提高了节点的抗震性能;下环板螺栓数量减少则降低了节点的抗震性能;增加RC板厚度和宽度提高了节点的承载能力,但降低了延性和耗能能力;RC板组合效应使节点中性轴在正、负弯矩作用下分别向上偏移钢梁截面高度的24.6%~45.1%、4.1%。同时,以试验结果与破坏特征为基础,考虑极限状态下RC板有效宽度,推导了梁端受弯承载力计算式,计算结果与试验结果吻合良好。
To investigate the impact of reinforced concrete(RC)slabs on the seismic performance of concrete-filled double-skin steel tubular(CFDST)column to steel beam joints with welded upper flanges and bolted lower flanges,low-cycle reversed loading tests were conducted on five composite joints.The effects of the presence or absence of RC slabs,the number of bolts in the lower ring plate,RC slab thickness,and RC slab width on the failure modes,hysteretic curves,bearing capacity,ductility,stiffness degradation,energy dissipation capacity,and strain patterns of the steel beam web were analyzed.The results indicate that the failure modes of the joints are characterized by fracture or buckling deformation at the connection between the upper flange and the upper ring plate of steel beam,horizontal slippage at the bolted connection area between the lower flange and the lower ring plate of steel beam,and compressive crushing and spalling of the RC slab concrete.The hysteretic curves of joints are relatively full and show no pinching effect,with rotational ductility coefficients ranging from 3.04 to 4.60.The presence of the RC slab improves seismic performance indices of the joints.Reducing the number of bolts in the lower ring plate decreases the seismic performance of the joints.Increasing the thickness and width of RC slabs enhances the bearing capacity but reduces ductility and energy dissipation capacity.Due to the composite effect of the RC slab,the neutral axis shifts upward by 24.6%-45.1% and 4.1% of the section height under sagging and hogging moments,respectively.Based on the test results and failure characteristics,a calculation formula for the flexural bearing capacity at the beam end was derived by considering the effective width of the RC slab under the ultimate state,and the calculated results were in good agreement with the test results.
作者
张冬芳
王昱
赵均海
李丹丹
樊聪聪
ZHANG Dongfang;WANG Yu;ZHAO Junhai;LI Dandan;FAN Congcong(School of Civil Engineering,Chang’an University,Xi’an 710061,China)
出处
《建筑结构学报》
北大核心
2025年第9期58-72,共15页
Journal of Building Structures
基金
国家自然科学基金项目(51508028,51878056)
陕西省重点研发计划项目(2025SF-YBXM-545)。
关键词
复式钢管混凝土柱
上焊下栓组合节点
钢筋混凝土板
拟静力试验
抗震性能
受弯承载力
concrete-filled double-skin steel tubular(CFDST)column
top-flange-welded and bottom-flangebolted composite joint
reinforced concrete(RC)slab
quasi-static test
seismic performance
flexural bearing capacity
