PBL剪力连接器的承载机理与屈服荷载

Load-Bearing Mechanism and Yield Load of PBL Shear Connectors

为了研究PBL剪力连接器的变形特征,通过4类9组共33个试件的加载试验,测试了外加荷载和PBL连接器变形,结合试件破坏形态,揭示了PBL剪力连接器在加载全过程的承载机理,探明了影响PBL连接器变形性能的主要因素.在此基础上,提出了PBL连接器屈服荷载的定义及计算公式.研究结果表明:PBL连接器的工作可分为拟弹性、弹塑性和屈服3个阶段;混凝土榫的剪断,导致PBL连接件屈服,屈服滑移量为1.2 mm;在弹性、弹塑性阶段由混凝土榫和钢筋共同承载;在屈服阶段,主要由芯棒钢筋承载;芯棒钢筋直径和强度、混凝土榫的直径是影响变形性能的主要因素,芯棒钢筋直径不宜小于16 mm.

In order to study the deformability of Perfobond Leiste （PBL）shear connectors,a series of tests were conducted to investigate the load-bearing mechanism and deformability influence factors of PBL shear connectors. In these tests,33 specimens divided into 4 types and 9 groups were loaded, and the external loads,deformation,and failure pattern of the specimens were probed. On this basis, the yield load of the PBL shear connector was defined,and a formula for yield load calculation was proposed. The results show that the deformation behavior of PBL connectors can be divided into the pseudo-elastic stage,the elasto-plastic stage,and the yield stage;and the yield is due to the shear fracture of concrete column. The slide at the yield point is about 1. 2 mm. Load is carried by concrete column and transverse steel bar in the pseudo-elastic stage and elasto-plastic stage,but only by transverse steel bar in the yield stage. Therefore,the diameter and strength of the transverse steel bar and the diameter of concrete column are the main factors influencing the deformation behavior of PBL shear connectors,and the diameter of the transverse steel bar should be more than 16 mm.