外置可更换耗能器的预制拼装自复位桥墩抗震性能试验研究

Based on the concept of seismic resilience design, combined with prefabricated structure technology, a self-centering prefabricated bridge pier structure with external replaceable energy dissipator was developed. The quasi-static cyclic loading tests for two groups of self-centering prefabricated pier model structures were conducted. The load-bearing behavior and damage process of a self-centering prefabricated pier in cyclic loading process were introduced, and its seismic performances, such as, force-displacement hysteresis curve, skeleton curve, energy dissipation capacity, tension change of prestressed reinforcement, residual displacement, joint opening, height of compression zone at the bottom of pier were analyzed. The results showed that the external energy dissipation components have good replaceability and energy dissipation capacity, pier seismic performance before and after replacement is basically the same; the force-displacement hysteretic curve of self-centering pier has obvious "flag" shape with smaller residual displacement and good self-centering ability; with increase in horizontal displacement of pier top, tension of axial prestressed reinforcement inside pier increases linearly, and the prestress loss of prestressed reinforcement decreases after energy dissipator is replaced; the steel pipe wrapped around pier bottom can effectively restrain local concrete collapse, and the steel pipe has no damage, such as, local bulge.