INFLUENCE OF INTER-STORY ISOLATION LEVELS ON THE SEISMIC RESPONSE OF MID-RISE AND HIGH-RISE REINFORCCONCRETE BUILDING

Abstract

Inter-story isolation system is a technique of isolating the portion of building at one or more intermediate story levels. It includes single story isolation and segmental isolation system. For a low rise building; base isolation system is highly effective system, but for a high rise building this system is not effective. This research was conducted on the relative effectiveness of different inter-story isolation levels; on the seismic response of mid-rise and high rise buildings. It includes both regular and setback irregular cases. Initially buildings were designed as reinforced concrete structures, and then lead rubber bearings were designed as nonlinear device. Each building category is designed for base isolation cases, and then each isolation systems were designed for 3second fundamental period and 15% damping. Finally based on the results and discussion the following conclusion was reached. On both mid-rise and high-rise building seismic response of base isolation, quarter-level isolation and segmental base& mid isolation systems have relatively smaller seismic response, and also mid isolation and three-quarter isolation system of regular high-rise building have relatively smaller seismic response. But mid story level symmetrical setback irregular mid-rise and high-rise buildings mid isolation and three-quarter isolation’s seismic response are much larger than other isolation system, specially threequarter level isolation system’s seismic response are greater than non-isolated building