摘要
竖向地震动在临近断层区较为强烈,这对具有低损伤特征的摇摆-自复位(rocking self-centering,RSC)桥墩构成了潜在的威胁。基于OpenSees平台建立了RSC桥墩有限元模型,与拟静力和振动台试验结果对比验证了建模方法的准确性。选取10条近场含脉冲地震波作为输入,分别以双向水平与三向激励2种工况对比,研究了竖向地震动对于RSC桥墩地震反应的影响。进一步扩展至含RSC桥墩的连续梁桥,以从整体上考虑桥梁上部结构的影响。结果表明:竖向地震动会使桥墩轴力增大,桥墩受压区最小高度减小,但从平均意义角度不是很显著,在不利的情况下,最大轴力可增加约19.55%,截面受压区最小高度降低约22.05%。总体而言,竖向地震动对RSC桥墩的墩顶最大位移影响不大。竖向地震动会很大程度改变RSC桥墩耗能钢筋拉应力及其破坏情况,由此对RSC桥墩及其桥梁结构抗震分析时有必要考虑竖向地震动的影响。
Vertical ground motion is more intense in the near-fault zones,which poses a potential threat to the rocking self-centering(RSC)column piers with low seismic damage characteristics.Based on the OpenSees platform,finite element model of RSCs was established,and the accuracy of the modeling method was validated by comparing simulation results with pseudo-static and shaking table test results.Ten near-filed ground motions with pulse-like waves were used as the earthquake inputs,and bidirectional horizontal excitation and the three-dimensional excitation were considered respectively.A research on the influence of vertical ground motion on the seismic response of RSCs,and the continuous beam bridge with RSCs was conducted.The results show that vertical ground motions can increase the maximum axial force of RSCs,and reduce the minimum height of the RSC section,but the changes are not significant on average.Under disadvantageous conditions,the maximum axial force can increase by about 19.55%,and the minimum height of the compression zone of the section can be reduced by about 22.05%.Overall,the vertical ground motion has a minor impact on the maximum displacement at the top of RSCs.Vertical ground motion can greatly change the tensile stress and failure of energy-dissipating steel bars in RSC bridge columns.Therefore,it is necessary to consider the vertical ground motion effects on seismic response estimation of RSC bridge columns and RSC bridge structures.
作者
王东升
张凯林
甄浩越
葛超洋
童磊
WANG Dongsheng;ZHANG Kailin;ZHEN Haoyue;GE Chaoyang;TONG Lei(School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300401,China)
出处
《地震工程与工程振动》
北大核心
2025年第4期64-74,共11页
Earthquake Engineering and Engineering Dynamics
基金
国家自然科学基金项目(52178473)。
关键词
摇摆-自复位桥墩
竖向地震动
数值分析
耗能钢筋
rocking self-centering(RSC)column piers
vertical ground motion
numerical analysis
energy-dissipating steel bars
