摘要
基础隔震技术由于良好的隔震性能在实际工程中得到广泛应用。现有的隔震结构分析方法主要采用宏观尺度(如弹簧单元)对其地震响应进行分析研究,隔震支座采用弹簧进行模拟时,该文模型只能反映结构的整体响应而未能考虑隔震支座及其他局部关键位置的细节。因此,为了解结构局部关键位置的力学性能(如隔震支座),该文提出一种考虑隔震支座特性的隔震结构多尺度模拟方法。首先,建立微观单元(实体单元)与宏观单元(梁单元)之间的多尺度界面连接方程;其次,通过不同尺度单元之间有效组合建立四种不同串联隔震体系模型(弹簧-梁单元模型、弹簧-实体单元模型、多尺度模型和全实体单元模型),在四种模型梁端施加往复荷载得到其滞回曲线,并与试验结果进行对比分析。分析结果表明,采用多尺度模拟方法不仅能掌握结构局部关键位置(隔震支座)受力特性,还可以提高计算效率,减少计算时间和存储空间,并在计算精度和计算代价之间得到了均衡。在此基础上,结合串联隔震结构振动台试验进一步验证多尺度分析方法的有效性。最后利用多尺度有限元模拟方法的优越性分析某基础隔震结构的动力响应。
Base-isolated techniques have been widely adopted in practical projects due to efficient isolation effects. The existing structural analysis methods of isolated structures principally utilize the macroscale model(spring element) to investigate the seismic behavior of isolated structure, which generally employs spring element to simulate isolation bearing. It can capture the overall response of isolated structures, but fails to consider the detailed characters of bearing isolation and other key components. In order to incorporate the mechanical properties of key components(such as isolation bearing), a multiscale finite element(FE) simulation method of isolated structure considering bearing isolation behaviors was proposed. Firstly, the multiscale interfacial connection equation between macroelement(beam element) and microelement(solid element) was formulated. Secondly, four series isolation systems(SIS) were formulated through the effective combination of the distinctive elements with different scales, including spring-beam model, spring-solid model, multiscale model(beam-solid model) and full-solid model(solid-solid model). The analyses of the aforementioned models simulated in Ansys, as well as testing results, were comparatively performed on the beam top under reversal loading. It illustrates that the multiscale simulation methodology can reflect the mechanical properties of key components(isolation bearing) and enhance computational efficiencies. The multiscale approach was further confirmed through a comparison with shaking table test results of SIS. Finally, the seismic behavior of base-isolated structure based on multiscale model was analyzed by the multiscale FEA method.
作者
李万润
王辉
孙玉萍
杜永峰
王雪平
吴忠铁
LI Wan-run;WANG Hui;SUN Yu-ping;DU Yong-feng;WANG Xue-ping;WU Zhong-tie(Lanzhou University of Technology,Earthquake Protection and Disaster Mitigation Institute,Lanzhou 730050,China;Lanzhou University of Technology,School of Civil Engineering,Lanzhou 730050,China;Lanzhou University of Technology,Disaster Prevention and Mitigation Engineering Research Center of Western Civil Engineering,Lanzhou 730050,China;Northwest University for Nationalities,School of Civil Engineering,Lanzhou 730050,China)
出处
《工程力学》
EI
CSCD
北大核心
2018年第6期115-122,131,共9页
Engineering Mechanics
基金
国家自然科学基金项目(51568041
51578274)
教育部长江学者创新团队项目(IRT13068)
兰州理工大学博士点基金项目
甘肃省住建厅科技攻关项目(JK2016-12)
关键词
隔震结构
多尺度建模
隔震支座
串联隔震体系
振动台试验
isolated structure
multiscale modeling
isolation bearing
series isolation system (SIS)
shaking table test