氯盐侵蚀下基于桥墩弯剪数值分析模型的RC桥墩抗震性能研究  

Seismic Performance of RC Bridge Pier Based on Shear Numerical Analysis Model under Chloride Ion Erosion

作　　者：张涵旖 ZHANG Hanyi(Collage of Civil Engineering,Institute of Disaster Prevention,Sanhe 065201,China)

机构地区：[1]防灾科技学院土木工程学院,河北三河065201

出　　处：《防灾科技学院学报》2024年第4期35-46,共12页Journal of Institute of Disaster Prevention

基　　金：中央高校基本科研业务费研究生科技创新基金资助(ZY20220316)。

摘　　要：近海桥梁所处环境氯离子浓度较高,桥墩在氯盐侵蚀下的抗震性能变化备受关注。以受氯盐侵蚀的钢筋混凝土桥墩为研究对象,结合Fick第二定律,计算不同腐蚀程度下的材料参数。基于OpenSees平台,结合Leborgne提出的模拟剪切强度退化的数值分析模型,通过计算剪切破坏时墩底塑性铰区域的转角θ_(f)监测剪切破坏发生时刻,建立氯盐侵蚀下的桥墩弯剪数值分析模型,并通过现有的腐蚀钢筋混凝土墩柱拟静力试验结果验证了模型的准确性。以北方某港口大桥为工程背景,建立数值分析模型,选取1999年中国台湾Chi-Chi地震中记录到的7条近断层地震动进行动力时程分析。结果表明:随着氯盐侵蚀作用进行,钢筋混凝土材料性能劣化严重,桥墩在服役期内的抗震位移需求逐渐增大,抗震性能降低,因此在近海桥梁结构的设计过程中考虑氯盐侵蚀作用是很有必要的。Since near-sea bridges are located in the environments with high concentrations of chloride ions,the seismic performance of bridge piers under chloride ion erosion have been of great concern.In this paper,the reinforced concrete(RC)bridge pier subjected to chloride ion action are studied,and the material parameters under dfferent corrosion levels are calculated by combining Fick's second law.With the help of OpenSees platform,combined with Leborgne shear strength degradation numerical analysis model,a bending-shear numerical analysis model of bridge pier under chloride ion erosion is established by calculating the rotation angle S,of plastic hinge area at the bottom of the pier during shear failure to monitor the moment of shear failure.Further,the accuracy of the model is verified by being compared with the existing quasi-static test data of corrosion RC pier column.Taking a harbor bridge in the north as the engineering background,we established a numerical analysis model,and selected seven near-fault ground motions of the 1999 Chi-Chi earthquake in Taiwan,China for dynamic time-history analysis.The results show that with the erosion of chloride ion,the performance of RC materials deteriorates seriously,the demand for seismic displacement of the bridge piers gradually increases during the service period,and the seismic performance decreases.Therefore it is necessary to consider the chloride ion erosion in the design of offshore bridge structures.

关 键 词：桥梁抗震性能 氯盐侵蚀 数值模拟 OPENSEES 

分 类 号：U442.5[建筑科学—桥梁与隧道工程] U443.22[交通运输工程—道路与铁道工程]