预应力预制框架节点修复机理试验研究

基于工程可修复及震后快速修复的需求,提出一种新型自复位预应力预制框架节点形式(PTED节点)。为了研究PTED节点的抗震性能,进行低周往复加载试验,试验结果表明,节点的弹塑性变形集中在耗能角钢上,梁、柱构件及预应力筋基本保持弹性,卸载后节点具有良好的自复位能力,残余变形小。基于PTED节点的自复位功能及损伤集中的特点,提出PTED节点的修复机理和修复方法,即震后利用预应力筋的回弹复位功能使结构恢复到正常状态,然后更换受损角钢完成修复。为了验证修复机理的正确性和修复方法的可行性,对修复后节点重新进行低周往复加载,试验结果表明,修复后节点的抗震能力与原节点基本等同。

REHABILITATION MECHANISM STUDY OF BEAM-TO-COLUMN CONNECTIONS FOR SELF-CENTERING POST-TENSIONED PRECAST FRAME

Based on the requirement of quick rehabilitation,a new kind of the self-centering post-tensioned precast connection( named PTED) was proposed. The tests of the PTED frame connections were carried out. The damage and mechanical characteristics of the connections under low reversed cyclic loading were studied. The results showed that the damage concentrates in the steel angles,the connections have the ability of self-centering and the residual deformation is small when unloading. Based on the self-centering capability of the PTED connection, the rehabilitation mechanism and the repair method were proposed,that is,after the earthquake the joint can returned to it's original position utilizing the self-centering capability of the post-tensioned steel and then just replace the damaged angle. The tests of the repaired PTED connection under low reversed were carried out and the repaired method was verified. The results showed that the seismic capacity of the repaired joint was basically the same as the original one.