半现浇榫卯节段预制桥墩滞回性能研究

Research on Hysteretic Performance of Local Cast-in-place Mortise-and-Tenon Joint Segment Prefabricated Pier

为克服传统无粘结预应力节段预制桥墩在水平往复荷载下接缝处易出现压碎破坏、滞回性能较差的缺点,在原有桥墩基础上进行改进,采用桥墩底部塑性铰区域与承台一同浇筑、其余部分节段预制的方式,考虑混凝土塑性损伤模型进行非线性拟静力加载计算。发现此种结构对比传统节段预制桥墩滞回性能有一定提升,结构受力控制截面转变为现浇部分与节段之间的接缝,并在此基础上在节段间加入榫卯结构与耗能钢筋,进一步提升了结构的延性与极限承载力。结构的破坏形式也由接缝间因开张与闭合产生的压碎破坏转变为墩底的弯曲破坏,滞回性能大幅提升,并具有更好的整体性。

In order to avoid the joint of traditional unbounded prestressed segment prefabricated pier being crushed under horizontal reciprocating load,and improving its poor hysteretic performance,Making change based on the original pier,the plastic hinge area at the bottom of the piers and pier foundation are poured together,other part is prefabricated.Through non-linear quasi-static loading calculation considering plastic damage model of concrete.It is found that this structure hysteretic performance has improved compared to traditional segment prefabricated pier,and structural force-controlled sections transform into joints between cast-in-place sections and segments.Next,mortise-and-tenon structure and energy-consuming steel bars be used into the segments,further improving the ductility and ultimate bearing capacity of the structure.The failure form of the structure also changed from crushing failure caused by opening and closing between the joints to bending failure at the bottom of the pier.Structure hysteresis performance is greatly improved,and has better integrity.