Aseismic Roof Isolation System: Feasibility Study with 13-Story Building

Abstract

An investigation is carried out of a 13-story building to assess the viability and effectiveness of a recently proposed roof isolation system that aims at reducing the response of buildings to earthquakes. The roof isolation system entails the insertion of flexible laminated rubber bearings between a building’s roof and the columns that support it, and the addition of viscous dampers connected between the roof and the rest of the building. It is based on the concept of a vibration absorber and the idea of constructing the mass, spring, and dashpot of such an absorber with the building’s roof, flexible bearings, and viscous dampers, respectively. The investigation includes a comparison of the building’s response under severe ground motion when it is considered with and without the isolation system, as well as determination of the properties and size of the isolation system components required. It is found that the proposed isolation system is effective, is able to be constructed, and has the potential to become an attractive way by which to reduce structural and nonstructural earthquake damage in low- and medium-rise buildings.