钢-混凝土组合梁中高强螺栓连接件的抗剪性能试验研究

Experimental study on shear behavior of high-strength bolt connection in steel-concrete composite beam

为研究高强螺栓连接件在钢-预制混凝土组合梁中的抗剪性能,对11个高强螺栓连接钢-混凝土组合试件进行了推出试验,分析了预紧力、螺栓直径、预留孔洞大小和混凝土强度等参数对高强螺栓连接件的破坏形态、荷载-滑移特性和受剪承载能力的影响。试验结果表明:高强螺栓连接件的破坏形态为螺栓周围混凝土受压破坏和螺栓栓杆在钢梁和混凝土界面间的弯剪破坏。高强螺栓在加载过程中,同时受到剪力、弯矩和拉力的共同作用,螺栓栓杆受力较为复杂。高强螺栓连接件受剪承载力主要受螺栓直径、混凝土强度的影响,适当增大螺栓的直径、提高混凝土强度,可提高螺栓连接件的受剪承载力。高强螺栓预紧力越大,初始滑移荷载越大,但对试件的受剪承载力影响较小。

In order to study the shear behavior of high strength bolt connection in steel-concrete composite beam,a total of eleven push-out specimens were tested. The tests were developed to investigate the failure modes, load-slip curves and the shear capacity of bolt connectors by changing parameters including bolt pretension, bolt diameter, diameter of prefabricated holes in steel and concrete, and compressive strength of concrete. Two failure modes were observed in the experiments: the compression damage of concrete around the bolt and the bending shear failure of the bolt at the interface between the steel beam and the concrete. The high-strength bolts were subjected to combined action of shear force, bending moment and tensile force. The bolt diameter and the compressive strength of concrete are the main parameters affecting the shear bearing capacity of bolted connector. The shear capacity of bolted connection increases with the diameter of the bolt and compressive strength of concrete. The change in pretension of high-strength bolt connection has significant effect on the initial slip load, but has less effect on the shear capacity.