【作者】 郑涛；

【导师】 谢异同；

【作者基本信息】 西安建筑科技大学 ， 防灾减灾工程及防护工程， 2009， 硕士

【摘要】 隔震结构是近三十年飞速发展的一种不同于传统结构的被动控制体系。在上部结构和基础之间引入一个侧向刚度小而竖向刚度大的隔震层,即通过隔震层的耗能装置,而不是由结构或结构构件来吸收消耗地震能量。本文以一个八层钢筋混凝土框架基础隔震结构为例：考虑到隔震结构周期较长的特点,结合实际地震动调整的小波方法,对结构输入调整前后的地震动进行抗震性能分析。本文主要从以下几个方面进行研究：(1)探讨了隔震结构在国内外的历史进展及未来发展趋势,分析隔震体系的基本原理,隔震装置的主要类型及性能并讨论了隔震技术及隔震结构计算方法。(2)对框架结构采用层剪切模型,对叠层橡胶支座采用双线性弹簧模拟,建立三维有限元分析模型,对结构的整体自振特性进行分析并探讨了高阶振型对结构地震反应的影响。以单向反应谱法和单向地震动输入对结构进行弹性地震反应分析,研究多遇地震作用下结构的整体受力变形,并为进一步研究隔震结构的动力特性打下基础。通过数值对比,得出隔震结构能大大减轻结构的水平地震作用,得到一些对实际隔震结构抗震设计有价值的结果。(3)基础隔震结构具有周期长、隔震层变形大的特点,规范对隔震结构时程分析输入地震动的选取规定不够统一。本文探讨了隔震结构时程分析输入地震动的新方法,对结构选波控制指标难于指导实际工程设计的现状提出新思路：考虑到小波分析方法具有自适应时频窗的优点,对地震动的调整具有很强的优越性,其能合理考虑场地类别、频谱特性、振幅对地震动的影响,尤其是对隔震结构敏感的低频长周期地震动。通过输入基于小波方法调整后的地震动,对隔震结构进行时程分析。比较调整前后结构的动力特性,以结构的基底剪力、顶层位移作为控制指标,以反应谱法计算结果作为基准,对调整前后的结果对比分析,认为调整后结构反应的离散性小,且调整后的基底剪力与反应谱法计算结果有更好的接近,即调整后的地震动更易满足规范对结构时程分析输入的选择要求,其计算方法能够更全面反映出设计地震动的特性,计算结果能更好地满足时程分析输入地震动的特征,为以后的实际工程抗震设计提供理论依据。更多还原

【Abstract】 Base-isolated structure is a passive control system different from the traditional structure in recently three decades of rapid development. There is a isolation layer of the lateral stiffness small and the vertical stiffness larger between the upper part of the structure and foundation. Through the consumption energy device of isolation layer, and not absorb the seismic energy by the structure or structure members. There is an eight-story reinforced concrete frame structure as an example of base-isolation in this paper. Considering the long period of base-isolated structure, with the wavelet method of the actual ground motion. Through input the ground motion of before and later adjustment to the structure for the performance of analysis earthquake-resistance. This paper studies mostly from the following aspects:(1) The discussion of the history and future trends of isolated at home and abroad, the analysis of the basic principles of isolation system, the main types of isolation devices and performance, discussed the isolation techniques and the calculation methods of isolation structure.(2) With shear-layer model on the frame structures, using the bi-linear spring simulation pairs of laminated rubber bearings, the three-dimensional finite element analysis model was established, the structure of the overall vibration characteristics was analyzed, and the seismic response of the higher-mode of buildings was explored. To further study the dynamic properties of isolated structures lay the foundation, the elastic seismic response of the structure by input the one-way response spectrum method and one-way ground motion was analysed, study the shear force and the deformation performance under the regular earthquake loading. Through numerical comparison, draw a conclusion:the base-isolated structure can greatly reduce the level of seismic action, some valuable conclusions of practical seismic design of isolated structures were obtained.(3) Base-isolated structure has the characteristics of long period, isolation layer deformation large, the code for seismic design of buildings has not unify the method of input ground motion of the time-history analysis. This paper discusses the new method of the input ground motion to time-history analysis of isolation structures, and bring forward the new ideas for the status selection of indicators structural wave control diffcult to guide practical engineering design:considering the advantages of self-adaptive time-frequency window of the wavelet analysis, and the strong advantage of the adjusted the ground motion, it can reasonably consider the response for the type of venue, spectral characteristics, amplitude of ground motion, especially for the low-frequency and long period ground motion which based on wavelet method adjustment. Comparing the dynamic properties of the structure with before and later adjusted wavelet, and the controlling index:basal shear force, the top-level displacement, the calculation of the response spectrum method as a benchmark. Comparing and alysising the result of the adjusted wavelet before and late, obtained the results the adjusted wavelet is smaller discrete, the adjusted wavelet of base shear is closer to the numerical calculated in the response spectrum method for the adjusted seismic waves regularly. Its calculation method more fully embodies the characteristics of the design earthquake motion, and its result can more fully reflect the characteristics of the design ground motion, and provide a theortical basis seismic design for the future practical engineering.更多还原