冷弯方钢管柱-H型钢梁外伸端板单向螺栓连接节点性能试验研究

为研究冷弯方钢管柱-H型钢梁外伸端板单向螺栓(hollo-bolt)连接节点的静力性能,对3个足尺寸的边柱节点进行了静力加载试验,试验研究参数为端板厚度和柱壁厚度。通过分析试验现象得到了不同端板厚度、柱壁厚度下单向螺栓连接节点的静力性能及破坏机理等,绘制了弯矩-转角曲线,对节点核心区各组件的应力-应变曲线进行了详细的分析。研究结果表明:随端板厚度增加,节点承载力不断增加,当端板厚度达到16mm后,端板厚度不再是节点承载力控制的主要因素;在其他条件不变的情况下,柱壁厚度对节点承载能力及转动能力有显著影响,柱壁厚度增加可有效提高节点刚度和承载能力。节点的极限转角较大,节点具有良好的变形能力,破坏形态主要有端板弯曲变形、单向螺栓套筒剪断和柱壁鼓曲变形破坏3种。

Experimental study on performance of the connection joints of cold-formed square steel tubular columns and H-shaped steel beams extension endplate using blind bolts

In order to study the static performance of the connection joints of cold-formed square steel tubular(CFST) columns and H-shaped steel beams extension endplate using blind bolts(hollo-bolt), the static loading test was carried out on 3 full-size side column joints, and the experimental research parametersis the endplate thickness and column wall thickness. Through analysis of experimental phenomena, the static performance and failure mechanism of blind bolt joints with different endplate thicknesses and column wall thicknesses were obtained. The bending moment-angle curve was drawn, and the stress-strain curve of each component in the core area of the joint was analyzed in detail. The results show that the bearing capacity of the joint increases continuously as the thickness of the endplate increases, but when the endplate thickness reaches 16 mm, the endplate thickness is no longer the main factor controlling the bearing capacity of the joint. When other conditions remain unchanged, the column wall thickness has a significant influence on the bearing capacity and rotational capacity of the joint. The increase in the thickness of the column wall can effectively improve the stiffness and bearing capacity of joint. The ultimate turning angle of the joint is larger and the joint has a large deformation capacity, and there are three main failure modes: endplate bending deformation, blind bolt sleeve shear cut and column wall bulging deformation.