【摘要】 为了探讨、比较焊接和螺栓连接钢框架的极限承载能力、滞回性能及动力特性,本文进行了6榀1∶2比例的单跨双层钢框架循环加载试验和动力特性测试,其中焊接、端板螺栓连接、角钢螺栓连接钢框架各两榀。试验过程中每层框架都铺设了混凝土楼板和配重,水平循环荷载按三角形分布施加。循环加载试验表明:当焊接连接框架的焊缝质量较高时,钢框架具有良好的承载能力和滞回性能,其最终破坏模式是构件形成塑性铰而发生强度破坏,属于典型的延性破坏,框架侧向层间塑性变形可以达到层高的1/25,塑性变形主要来自梁柱连接节点域的剪切变形和柱、梁的弯曲变形;端板螺栓连接框架的承载能力和滞回性能也较好,耗能能力略低于焊接框架,框架侧向层间塑性变形可以达到层高的1/30,但端板焊缝容易发生断裂;角钢螺栓连接框架的承载能力和耗能能力相对较低,塑性变形主要发生在连接角钢和柱脚部位,且翼缘连接角钢容易发生低周疲劳破坏。动力特性测试结果表明:随着节点转动刚度的减小,框架自振周期延长。更多还原

【Abstract】 In order to investigate and compare the ultimate load-carrying capacity,hysteretic behavior and dynamic characteristics of welded and bolted steel frames;6 single-span two-story steel frames were tested under cyclic loading.There were 2 welded,end-plate bolted and angle bolted frames apiece.During the test,concrete floor were laid and vertical weight was applied on every floor.Triangle horizontal loads were applied to frames cyclically.Experimental results show that the welded frames with high quality connection welding have better load-carrying capacity and hysteretic behavior.The reason for the fracture is that the plastic hinges broke,and the failure is the typical ductility mode.The plastic story drifts can reach(1/25) of the height of the story. The plastic deformations are mainly caused by the shear deformation of the panel zone in beam-to-column connections,and the bending deflections of column and beam.End-plate bolted frames also have better load-carrying capacity and hysteretic behavior,while the dissipation capacity is a little lower than that of the welded frames.The plastic story drifts can reach 1/30 of the height of the story,but the end-plate welds are easy to crack.For angle bolted frames,the load-carrying capacity and hysteretic behavior are much lower than those of the welded frames.The plastic deformations mainly occur in flange angles and column feet.The flange angles are easy to cause low-cycle fatigue fracture.Dynamic characteristics tests show that the natural vibration period of steel frame can be prolonged with the reducing of connection rotation stiffness.更多还原