预应力混凝土管桩与承台连接节点抗震性能试验研究

Experimental research on seismic performances of prestressed high-strength concrete pipe piles and pile-pile cap connections

通过6个预应力混凝土管桩与承台连接节点的低周往复荷载试验,描述了连接节点的破坏过程和破坏形态,并分析了试验过程中桩身混凝土应力和锚固钢筋的的应变,对试件的滞回性能、承载力能力进行了研究,考虑了不同连接形式对节点抗震性能的影响。试验结果表明,试件均发生受弯破坏,破坏形态有两种:预应力钢筋被拉断,发生脆性破坏;锚固钢筋屈服,节点区破坏严重,发生延性破坏。另外,节点的转动性能越好,其滞回性能越好,承载力越高。

Based on the results of six prestressed high-strength concrete pipe piles and pile-pile cap connections under cyclic loading, the failure patterns and the mechanism of the specimens are described. The stresses of piles, strains of anchor bars, hysteretic performances and bearing capacities of different connections are analyzed. It is shown that the specimens appear to be flexural failure from the test results. There are two kinds of failure modes observed in the tests: the failure is sudden and brittle because of the fracture of prestressing tendon, and the connections are severely damaged because of the yielding of anchor bars and appearing of the plastic hinge. In addition, the bearing capacities and hysteretic performances increase with the rotation capacity of pile connections.