装配式栓钉剪力连接件抗剪承载力试验研究

Experimental Study on Shear Capacity of Prefabricated Composite Shear Stud

为探索装配式栓钉在荷载作用下的力学性能,设计了2个大比例尺的预制装配式栓钉剪力连接件,通过推出试验研究其破坏过程、荷载滑移曲线、抗剪性能和极限承载力。研究结果表明:当栓钉被剪断时,栓钉根部剪断位置处有颈缩现象且局部混凝土剥落,栓钉周边混凝土仅出现细小裂纹,没有明显贯穿式裂纹;由于桥道板板肋处混凝土受传力钢板的约束作用使得板肋处混凝土和钢结构间摩擦力增大,进而提高了装配式栓钉剪力连接件的抗剪承载能力;在考虑滑移沿试件高度不均匀分布系数对结构影响的基础上,推导了在考虑混凝土弹性模量、栓钉弹性模量、栓钉直径、栓钉数量等因素的装配式栓钉剪力连接件单钉极限承载力理论计算公式,且计算结果的安全富余度满足规范要求,与试验结果相比,误差在5%以内,吻合较好。

In order to explore the mechanical properties of the prefabricated studs under load action two large scale prefabricated composite shear stud(PCSS)were designed.The failure process load slip curve shear resistance and ultimate bearing capacity of studs were obtained by push out test.The judgment mark at the end of this test is the shear failure of studs.The research results show that when the stud is cut off there is necking phenomenon at the cutting position of the stud root and local concrete peeling off.There are only small cracks in the concrete around the stud and no obvious penetration cracks.Because of the restraint effect of the steel plate on the concrete at the rib of the bridge slab the friction between the rib concrete and the steel structure increases and the shear bearing capacity of the prefabricated composite shear stud is improved.Based on the influence of the uneven distribution coefficient of the slip along the height of the specimen on the structure the theoretical formulas for calculating the ultimate bearing capacity of single stud of prefabricated composite shear stud are derived considering the factors of concrete elastic modulus stud elastic modulus stud diameter and number of studs.The safety redundancy of the calculated results meets the requirements of the code.Compared with the test results the error is less than 5%which is in good agreement.