新型单面螺栓梁柱外伸端板连接节点受力性能试验研究

Experimental study on mechanical properties for extended end-plate connections of beam-column joints using new blind bolt

为研究新型自紧高强单面螺栓SHSOB连接节点的受力性能,并与传统M20扭剪型高强螺栓连接节点进行对比,设计制作了3个方矩形钢管柱与H形钢梁的外伸式端板连接节点试件,包括2个SHSOB螺栓连接节点和1个M20螺栓连接节点,对各节点试件开展了静力加载试验.揭示了节点的受力性能与破坏模式,考察了新型SHSOB螺栓连接节点的转动刚度、承载力和螺栓群受力分布模式.结果表明,SHSOB螺栓连接节点的初始转动刚度低于M20螺栓连接节点,节点转角大于0.03 rad,满足美国规范FEMA-350对节点延性的要求.随着荷载的增加,端板受拉区应力先增大后趋于稳定.SHSOB螺栓连接节点属于半刚性节点,螺栓群受力分布模式与传统的高强螺栓相似,中和轴位于螺栓群形心附近,具有较好的工程适用性.

To study the mechanical properties of joints connected by a new type of self-tightening high strength one-side bolt(SHSOB),and compare with the joints connected by traditional M20 high-strength torsional shear bolts,three specimens of the extended end-plate connections of square steel tube columns and H-shaped steel beams were designed and manufactured,including two joints connected by SHSOB bolts and one joint connected by M20 bolts.The static loading tests were carried out on the specimens to reveal the mechanical properties and the failure modes of the joints.The rotational stiffness,bearing capacity,and stress distribution modes of the bolt group were investigated.The results show that the initial rotational stiffness of the joint connected by SHSOB bolts is lower than that by M20 bolts.The joint angle of the joint connected by SHSOB bolts is greater than 0.03 rad,meeting the ductility requirements of the American standard FEMA-350.Moreover,with the increase of the load,the stress in the tensile zone of the end-plate increases first and then tends to be stable.The joints connected by SHSOB bolts belong to semi-rigid joints.The stress distribution pattern of the bolt group is similar to that of the traditional high-strength bolts,and the neutral axis is located near the centroid of the bolt group,thus showing that SHSOB bolt has a good engineering applicability.