考虑高阶振型的改进能力谱法在铁路高桥墩中的应用  

Application of improved capacity spectrum method considering high-order mode to tall pier of railway bridge

作　　者：李宇[1] 潘彪[1] 李琛[2] 

机构地区：[1]长安大学旧桥检测与加固技术交通行业重点试验室,陕西西安710064 [2]长安大学建筑学院,陕西西安710064

出　　处：《土木工程学报》2016年第8期92-98,共7页China Civil Engineering Journal

基　　金：国家自然科学基金(51408042);陕西省自然科学基础研究基金面上项目(2015JM5156);陕西省教育厅专项科研项目(15JK1422);西安市建设科技项目(SJW2014012);中央高校基本科研业务费专项资金(0009-2014G1211006)

摘　　要：以我国《铁路工程抗震设计规范》为依据,在前人建议的模态分析Pushover法的基础上,针对我国大跨铁路桥梁中的高桥墩,提出能考虑高阶振型影响的改进能力谱法,并以内昆线花土坡铁路特大桥8#墩为实例,验证了改进方法评估高桥墩抗震性能的合理性,得到如下结论:1提出能考虑高阶振型的公式,使模态分析Pushover法能更好地考虑高阶振型的影响;2选取四类场地320条强震记录,统计了与我国《铁路工程抗震设计规范》相应的强度折减系数谱和弹塑性需求谱,为改进方法提供设计谱;2以墩高110m的8#墩为例,验证了考虑高阶振型的改进能力谱法应用于桥梁抗震性能评估的合理性。综上所述,研究成果可为同类工程抗震性能的研究提供有益参考。Based on the Code of Seismic Design for Railway Engineering and the modal Pushover analysis, an improved capacity spectrum method with high-order mode considered was proposed for the tall piers of large-span railway bridges. Furthermore, the rationality of the improved capacity spectrum method was validated based on the 8# tall pier of Huatupo railway bridge of Neijiang-Kunming railway line. Some meaningful conclusions are drawn as follows. 1 ） Calculation formulas considering high-order mode are proposed for improving the modal Pushover analysis. 2） According to the Code of Seismic Design for Railway Engineering, 320 records of strong earthquakes are appropriately selected to statistically derive the elasto-plastic demand spectra and strength reduction factor spectra as design spectra for improving the capacity spectrum method. 3 ） Based on the 8# tall pier with the height of 110m, the practicability of improved capacity spectrum method considering high-order mode for seismic performance assessment of bridges is validated. Therefore, research achievements in this study can be referred by the researches in similar projects.

关 键 词：超高桥墩 高阶振型 能力谱法 推倒分析 有限元 

分 类 号：TU442.5[建筑科学—岩土工程]