为避免钢结构露出型柱脚在地震中发生破坏,研究一种新的减震装置。该装置通过楔块滑动、弹簧变形和螺杆的塑性伸长来控制柱脚位移,同时消耗地震能量,达到消能减震的效果。采用方形空心钢管柱,分别对普通螺栓柱脚和带减震装置的柱脚进行低周往复加载试验,研究其恢复力特性。试验表明:普通螺栓连接的柱脚呈滑移型滞回特征;由于弹簧恢复和楔块切入,新型柱脚连接每次加载卸载均以原点为始终,呈无滑移型滞回特征。根据试验结果,得到了带楔块装置钢柱脚的无滑移型恢复力模型。研究结果表明,无滑移型减震连接的钢柱脚具有良好的抗震性能且简单易用。
A new isolation device was designed to avoid damage of steel exposed-column base in earthquake,which consists of a wedge compressed by a spring and a counter-wedge.By the plastic elongation of the anchor bolt,the deformation of the spring and the slip of the wedge,the device can effectively dissipate the earthquake energy and control the damage of the structure.Dynamic cyclic test was performed to study the hysteretic behaviors of steel exposed-column base with and without the device.The results show that the ordinary column base is observed to be slip-type due to a gap between the nut of the anchor bolt and the base plate,caused by the plastic elongation of the anchor bolt.The new isolation column base is observed to be non-slip-type due to the gap which can be eliminated by use of the new device.Based on test results,a new non-slip-type hysteretic model is proposed.The results show that this device provides a better seismic performance and can be used conveniently.