考虑退化效应的滑移铅芯橡胶支座力学性能精细建模与模型验证  

Numerical simulation and model validation of sliding-lead rubber bearing considering cyclic degradation effect

作　　者：郑文智 王浩[3] 谭平[1,2] 刘彦辉[2] 杜永峰[4] Zheng Wenzhi;Wang Hao;Tan Ping;Liu Yanhui;Du Yongfenga(School of Civil Engineering,Guangzhou University,Guangzhou 510006,China;Key Laboratory of Earthquake Resistance Earthquake Mitigation&Structural Safety of the Ministry of Education,Guangzhou University,Guangzhou 510006,China;Key Laboratory of C&PC Structures of the Ministry of Education,Southeast University,Nanjing 210096,China;Institute of Earthquake Protection and Disaster Mitigation,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]广州大学土木工程学院,广东广州510006 [2]广州大学工程抗震减震与结构安全教育部重点实验室,广东广州510006 [3]东南大学混凝土及预应力混凝土结构教育部重点实验室,江苏南京210096 [4]兰州理工大学防震减灾研究所,甘肃兰州730050

出　　处：《土木工程学报》2022年第10期11-21,61,共12页China Civil Engineering Journal

基　　金：国家重点基础研发计划(2019YFE0112500);国家自然科学基金(52108278,51978185,51778163);教育部长江学者创新团队(IRT13057)。

摘　　要：隔震支座是隔震结构地震响应控制的关键构件,滑移铅芯橡胶隔震支座具有协调上部结构温致变形、地震作用下可耗能复位等优势,但往复荷载作用下其力学性能退化显著。文章建立考虑支座性能退化的滑移铅芯橡胶支座精细数值模型,开展不同竖向压力、加载频率、加载位移幅值时滑移铅芯橡胶支座压剪力学性能分析,并基于支座试验结果验证模型的准确性,进一步探明支座性能退化对隔震桥梁地震响应的影响。结果表明:竖向压力增大会改变滑移铅芯橡胶支座的滞回力-位移关系,从而提升其耗能性能;加载频率对摩擦力的影响随加载频率增大而显著减小;加载位移幅值越大,支座单周耗能能力、等效刚度随滞回周期的增加减小越显著;相比已有数值模型,考虑支座性能退化的精细数值模型分析结果与试验结果吻合更好,模型误差显著减小。隔震周期越大,支座性能退化对隔震桥梁地震响应的影响越显著,应在隔震结构设计与性能分析中予以关注。Seismic isolation bearing is the key component for response mitigation of seismically isolated structures.Sliding-lead rubber bearing(sliding-LRB) has the advantages of accommodating the thermal-induced structural deformations and seismic isolation subjected to earthquakes, whereas its mechanical performance degrades significantly under cyclic loadings.A refined numerical model for sliding-LRB considering cyclic-induced degradation effect was developed, and based on the model, the compression-shear performance of sliding-LRB subjected to different vertical loads, shear frequency and displacement amplitude was numerically analyzed.Furthermore, the accuracy of the model was validated by the test results and the cyclic-induced degradation effect on the response of seismic-isolated bridges was investigated.Results show that the increase of the vertical force may change the hysteretic force-displacement relationship of sliding-LRB, and thus enhance its energy dissipation capacity.The influence of the loading frequency on the friction force may be reduced significantly with the increase of the loading frequency.The larger the displacement amplitude is, the more evident the decreases of the energy dissipation in each cycle and equivalent stiffness with the increase of hysteretic loops shall be.Compared with the previous numerical model, the analysis results of the developednumerical model including cyclic-induced degradation effect agree well with the experimental values, and the model error is effectively reduced.With the increase of structural isolation period, the cyclic-induced degradation effect on the response of seismic-isolated bridges is more evident and attention shall be paid in structural seismic isolation design and performance analysis.

关 键 词：滑移支座 铅芯橡胶支座 性能退化 数值模拟 模型验证 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]