摇摆双层桥梁地震反应及抗倒塌能力分析  

ANALYSIS OF SEISMIC RESPONSE AND OVERTURNING RESISTANCE OF ROCKING DOUBLE-DECK BRIDGE SYSTEM

作　　者：陈敬一 杜修力[1] 韩强[1] 周雨龙 CHEN Jing-yi;DU Xiu-li;HAN Qiang;ZHOU Yu-long(Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education,Beijing University of Technology,Beijing 100124,China;Research Institute of Highway Ministry of Transport,Beijing 100088,China)

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124 [2]交通运输部公路科学研究院,北京100088

出　　处：《工程力学》2020年第10期56-69,共14页Engineering Mechanics

基　　金：国家重点研发计划项目(2018YFC1504305);国家自然科学基金创新研究群体项目(51421005);国家自然科学基金项目(51878016)。

摘　　要：针对常规延性设计的现浇双层桥梁在地震损伤控制方面的不足,该文提出一种摇摆双层桥梁结构。采用拉格朗日方程和动量矩定理建立了可计算该类摇摆桥梁结构动力反应的刚体分析模型,分析了结构的地震反应,探讨了桥墩宽高比和桥墩尺寸参数等模型参数对其地震反应的影响,并采用脉冲近场地震动数学模型Ricker小波对结构的抗倒塌能力进行了定性和定量的分析。研究结果表明:在横桥向地震作用下,采用工程实际尺寸的摇摆双层桥梁结构在E2地震水准下未发生倒塌且上层结构未见塑性损伤;与远场地震相比,脉冲近场地震更易使结构发生倒塌;给出了结构在Ricker小波作用下的倒塌加速度谱和倒塌模式,结构抗倒塌能力随着桥墩宽高比和桥墩尺寸参数的增大而显著提高。Double-deck viaducts based on traditional ductility design are vulnerable to earthquake-induced damage.To control the seismic damage,a double-deck bridge is developed with the lower floor designed as a rocking structure.To investigate the dynamic response of the rocking bridge,an analytical model of rigid bodies is derived through the Lagrange method and momentum conservation law.The seismic response analysis and parametric analysis adopted structural parameters such as the size and dimension parameter of columns are performed using this model.The overturning resistance of the rocking double-deck bridge is estimated qualitatively and quantitatively with a mathematical model of Ricker wavelets.The results show that the rocking double-deck bridge with dimension in practice can satisfy the seismic design demand of the E2 earthquake according to the seismic design code of bridges in China.However,the rocking bridge is more prone to overturn under near-fault ground motions with a high amplitude velocity pulse.The overturning acceleration spectra and overturning modes of a rocking double-deck bridge system were obtained due to Ricker wavelets.The rocking bridge is more stable with the larger slenderness and size of columns.

关 键 词：双层桥梁 摇摆结构 分析模型 地震反应 抗倒塌能力 

分 类 号：U442.5[建筑科学—桥梁与隧道工程]