摇摆式预应力混凝土桥墩基于位移的抗震设计方法研究

PDF(1421 KB)

振动与冲击 ›› 2014, Vol. 33 ›› Issue (24) : 106-111.

论文

摇摆式预应力混凝土桥墩基于位移的抗震设计方法研究

王军文1,2 张伟光1,2 李建中3

作者信息 +

Study on Displacement-based Seismic Design Procedures of Rocking Bridge Piers With Posttensioned Tendons

Wang Junwen1,2 Zhuang Weiguang1,2 Li Jianzhong3

Author information +

文章历史 +

摘要

本文根据基于性能抗震设计的思想，提出一种摇摆式预应力混凝土桥墩基于位移的抗震设计方法。该方法根据桥梁抗震设防水准确定桥墩的损伤水平，并考虑墩底接缝区变形的影响计算桥墩的目标位移；借助非弹性位移谱计算桥墩的位移需求。摇摆式预应力混凝土桥墩在墩底接缝区设置耗能钢筋或外部耗能装置来耗能地震能量，利用无粘结后张拉钢束在接缝处产生的摩擦力提供剪切抗力，合理设计预应力钢束的初张力，使其在地震荷载作用下保持在弹性范围内，保证其良好的复位能力。通过与已有的设计方法相比，评估了所提出的设计方法的可靠性。研究结果表明：与已有的设计方法相比，用本文提出的摇摆式预应力混凝土桥墩基于位移的抗震设计方法的设计结果与非线性时程分析结果的相关性更好。

Abstract

Based on performance-based design philosophy, a displacement-based seismic design procedure for rocking bridge piers with post tensioning tendons is developed. In this design procedure, the level of piers damage is determined on the basis of earthquake fortification level, target displacement of piers is estimated considering the effect of deformation of the interface region where piers connect to footings; with inelastic response spectrum, the displacement demand under the earthquake is calculated. Energy dissipation bars or additional external dissipation devices in the piers-to-foundation critical interface region are used to dissipate earthquake energy by yielding, unbonded post-tensioning tendons are used to provide the shear resistance through friction developed at the pier-to-footings interface by the post-tensioning force, the initial tension of tendons is designed in details to maintain stress in tendons in the elastic range, and negligible residual displacements of piers are expected. The reliability of this design procedure is assessed by comparison with existing design procedures. The results of studies show that, compared with existing design procedures, the proposed design procedure gives results that is more consistent with the results of nonlinear time-history analysis.

导出引用

王军文;张伟光;李建中. 摇摆式预应力混凝土桥墩基于位移的抗震设计方法研究[J]. 振动与冲击, 2014, 33(24): 106-111

Wang Junwen;Zhuang Weiguang;Li Jianzhong. Study on Displacement-based Seismic Design Procedures of Rocking Bridge Piers With Posttensioned Tendons[J]. Journal of Vibration and Shock, 2014, 33(24): 106-111