Study on Structures and Equipments Supported on Seismic Isolator

近年来，隔震系统的研究及其实现方法的发展十分活跃。本研究的目的是在各种地震系统中寻找可行、可用且足够的支撑系统，这些地震系统仅限于通过为建筑物或机器提供非常软的弹簧来降低地震功率的类型，讨论了具有叠层橡胶支座和某种消能工组成的减震系统的多层钢筋混凝土建筑的动力特性。采用粘性、摩擦和滞回型消能工。分别对固体地基和软土地基的输入地震反应进行了模拟。对叠层橡胶和消能减震器进行了精确的参数研究。并对非隔震结构和隔震结构的地震反应进行了比较，说明隔震结构能有效地减小地震能量向上部的传递。隔震效果越好，地震功率级越高。从控制地震后残余的大位移反应的角度考虑，如何选择消能工是一个重要问题，隔震建筑的楼层反应谱表明，建筑中的次要结构和设备可以避免强烈的地震作用。隔震反应谱与非隔震反应谱相比，无明显的优势频率。特别是摩擦耗能器，没有出现窄带峰值，叠层橡胶支座隔震器可能会引起摇摆振动。还进行了摇摆振动的分析。获得了定量结果。

Recently, Researches for seismic isolation systems and the development of the realization of them have been highly activated. The objective of this study lays in searching for the feasible, available and adequate supporting system among various seismic systems limited to the type that can reduce the seismic power by means of providing buildings or machines with very soft springs.Dynamic chraracteristics of multi-storied RC buildings provided with seismic isolation systems, which consists of laminated rubber bearings and some kind of dissipators, are discussed. Viscous, frictional and hysteretic types are adopted as dissipators. Simulations of response to input earthquakes which corresponds to the solid and soft ground have been carried out. The precise parameter study of laminated rubbers and dissipators has been also carried out. Furthermore seismic response of non isolated building is compared with isolated one.Suffice to say that the seismic isolater can reduces the seismic power into the upper part of buildings. The more effective the seismic isolator become, the higher earthquake power level is. From the point of controlling large response displacement which remains after earthquake, it is important how to select the type of dissipators.Response spectra of the floor response obtained in the isolated building reveal that secondary structures and equipments in the building may be made free from severe excitations. Accelaration response spectra, compared with that of the non isolated building, has no distinct predominant frequencys. Especially in the case of frictional dissipators, no narrow band peak appears.Rocking vibrations may be induced by the seismic isolator using laminated rubber bearings. Analysis of rocking vibrations has been also carried out. Quantitative results are obtained.