腹板嵌入式组合梁中抗剪连接件推出试验

Push-out experimental study on shear connectors in embedded composite beams with notched web

提出一种节省钢材且具有较高受剪承载力的新型组合梁——腹板嵌入式钢-混凝土组合梁,它是将倒T形钢梁腹板上部开槽,嵌入到混凝土翼板中形成的组合梁。通过10个推出试件的试验,研究腹板嵌入式组合梁中钢板连接件的受剪承载力。推出试验结果表明,连接件的受剪承载力随混凝土强度等级、钢板厚度增加而提高。基于试验结果,通过参数回归分析,拟合出嵌入式组合梁连接件受剪承载力计算公式,并提出连接件的构造要求。通过与普通组合梁中栓钉连接件受剪承载力的比较表明,腹板嵌入式钢-混凝土组合梁中钢板连接件具有承载力高、易于实现完全抗剪连接的优点,而且连接件抗剪连接刚度大,可以减少组合梁由于滑移效应引起的刚度折减。

Based on the ordinary steel-concrete composite beam, a novel embedded composite beam which not only had higher shear bearing capacity but also could save steel was proposed. The embedded composite beam consists of the steel beam with reverse T section which has notches on the top of the web and is embedded in the concrete slab. Through the test of 10 push-out specimens, the bearing capacity of the shear connector in the embedded composite beam is researched. Test results show that the bearing capacity of the shear connector increases with the improvement of the concrete grade and the thickness of the steel plate. Based on the test results, the formulas to calculate the shear bearing capacity of the notched web connectors was developed based on parametric analysis and the configuration requirements on the shear connector in embedded composite beams. The bearing capacities of the shear studs in ordinary composite beams were compared with that of the shear connector in embedded composite beams, which indicated that the notched web connector not only had higher shear bearing capacity and easier possibility to develop totally shear connection, but also could decrease the reduction of the stiffness of the composite beam caused by sliding effect.