砂土场地桩柱式墩桥梁桩身地震需求简化计算方法  

SIMPLIFIED SEISMIC DEMAND PREDICTION METHOD FOR EXTENDED PILE-SHAFTS IN COHESIONLESS SOILS

作　　者：王晓伟[1] 钱晋 叶爱君[1] 王靖程 杨光怡 WANG Xiao-wei;QIAN Jin;YE Ai-jun;WANG Jing-cheng;YANG Guang-yi(State Key Laboratory for Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学土木工程防灾减灾全国重点实验室,上海200092

出　　处：《工程力学》2024年第12期150-157,共8页Engineering Mechanics

基　　金：国家自然科学基金项目(52008155,52178155);土木工程防灾国家重点实验室项目(SLDRCE19-B-20)。

摘　　要：桩柱式墩是桥梁工程中广泛采用的下部结构形式,但如果桩身没有进行有效的能力保护设计,在地震作用下可能形成塑性铰。由于土桩动力相互作用的复杂影响,如何根据墩柱塑性铰区截面的超强弯矩计算桩身的抗震需求,依然是桩柱式墩桥梁延性抗震设计中的技术难题。基于土-桩-结构一体化模型,对桩柱式墩桥梁的延性抗震设计方法开展研究,重点解决桩身地震需求的简化计算问题。通过开展不同地震强度下桩柱弯矩分布发展规律研究,确定了桩身地震需求参数;通过桩身地震需求参数敏感性分析,结合大量参数分析及多元线性回归方法,建立了桩身地震需求参数与土体、结构参数之间的关联关系,提出了基于能力保护的桩身抗弯需求和加强配筋范围的简化计算方法。研究成果可为我国桩柱式墩桥梁延性抗震设计方法的改进提供依据。The pile-shaft is a substructure widely used in bridge engineering.Under earthquake,the pile may yield if the capacity protection design principle is not well followed.Due to the complex soil-pile interaction in modeling and analysis,it is still difficult to predict the seismic demand of piles based on the yielding moments of piers.Therefore a coupled soil-pile-structure model are adopted to investigate the ductility seismic design method of pile-shafts with a focus on the simplified seismic demand prediction method.Investigations are conducted on the bending moment distribution under different earthquake intensities to determine pile-shaft demand parameters,and extensive parametric analyses are performed to understand the mathematical relationship between pile-shaft demand parameters and soil/structural sensitive parameters.A simplified seismic demand prediction method is proposed.

关 键 词：桥梁工程 桩柱式墩桥梁 桩身地震需求 能力保护构件 简化计算方法 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]