CFRP加固对预制节段拼装桥墩抗震性能的影响

Effect of CFRP Sheets on Seismic Performance of Precast Segmental Piers

摘要:

为提升预制节段拼装桥墩的抗震性能，采用碳纤维增强复合材料(CFRP)对预制节段拼装桥墩在地震中易损伤部位进行加固。基于既有试验，建立缩尺的预制节段拼装桥墩三维实体有限元模型，分析预制节段拼装桥墩在循环往复荷载情况下的恢复力特性以及破坏情况。分别采用箍筋加密和外包CFRP布对预制节段拼装桥墩底部节段进行加固，对比两种加固方式对预制节段拼装桥墩抗震性能的影响。研究结果表明，CFRP包裹桥墩底部节段能够增强桥墩整体刚度和承载能力，并且使得桥墩的刚度退化更加平缓，有利于预制节段拼装桥墩在地震作用下保持自身力学特性的稳定，确保桥梁整体的安全。

Abstract:

To improve the seismic performance of precast segmental piers during earthquake, carbon-fiber-reinforced plastics (CFRPs) were used to reinforce the vulnerable parts of precast segmental piers. Based on the results of previous experiments, we established a three-dimensional solid finite element model of a precast segmental pier and analyzed the restoring force characteristics and damage sustained by the pier under cyclic loading. After reinforcing the bottom segments of the pier with either stirrup reinforcement or an outsourced CFRP sheet, we compared the effects of the two reinforcement methods on its seismic performance. The results showed that the bottom section of the CFRP-wrapped pier enhanced the overall stiffness and bearing capacity of the pier and made the stiffness degradation of the pier gentler. Based on the results, we can conclude that CFRP reinforcement is conducive to the stability of the precast segmental pier under earthquake and can better ensure the safety of the bridge.