一种新型装配式钢-混组合梁板连接件推出试验研究

Push-out Test Study on a New Type of Shear Connector Applied in Prefabricated Steel-concrete Composite Beam-slab Structure

为了提高装配式钢-混组合结构施工的便利性和高效性,本文提出了一种新型的可用于钢-混组合结构梁板的焊接螺栓抗剪连接件.设计并制作了3个试件和1个采用普通剪力钉制作的对比连接件.通过推出试验分别研究了采用不同连接方式连接件的荷载位移曲线、承载及变形能力、破坏机理等力学性能.结果表明:剪力钉与螺栓钉材料的屈强比相似,受混凝土影响相对较小.通过对抗剪连接件推出试验整体分析可知,主要经历弹性、弹塑性和破坏三个阶段.在螺栓钉根部的焊接螺母有效尺寸越大,对试件整体受力性能越有利.由于螺杆上螺纹截面不规则,削弱了其有效面积,易产生应力集中.试件破坏多为螺杆产生断裂或拔出破坏,表明在螺栓钉与钢板之间连接有效.在复杂实际工程中,采用螺栓钉进行连接具有一定优势,提高了装配效率,应用前景良好.

In order to further improve the construction convenience and efficiency of prefabricated steel-concrete composite structure,a new weldable bolt shear connector for steel-concrete composite beam-slab structure was proposed in this paper.A group of three steel-concrete composite members were designed and manufactured with this kind of connectors,and a specimen with big head shear studs were used as the comparison sample.The load-displacement curves,load-bearing capacity and deformation capacity,failure mode and other mechanical properties of the steel-concrete composite members with different connectors were studied by push-out test.The results show that the proposed weldable bolt connector and shear stud connector have similar yield ratio and are less affected by concrete.According to the overall analysis of the push-out test of the members,the test process mainly goes through three stages:elastic,elastic-plastic and failure.The large the size of the weld nut at the root of the bolt,the better the mechanical properties of the specimen.Because the screw thread section is irregular,the bolts are easy to produce stress concentration.The failure of all members used weldable bolts are screw fracture or pull-out failure of the screw,which proves that the connection mode between weldable bolt shear connector and steel plate is firm and reliable.Therefore,in complex practical engineering,the use of weldable bolt shear connector improves assembly efficiency,with certain advantages and a good application prospect.