Probabilistic Behavior Assessment of Base-Isolated Buildings and Base Isolation Systems Subjected to Various Earthquakes with Different Components

Abstract

One of the greatest challenges of researchers is to understand the behavior of base isolation systems and base-isolated buildings under the conditions of different ground motions. The specific objective of this study is to evaluate the seismic response of multi-story base-isolated buildings with lead core rubber bearings (LCRBs) and buildings that are not isolated when subjected to different types of ground motions with different components. Under these conditions, the equations of motion of buildings with isolation systems are obtained, and LCRB force-deformation behavior is modeled as bilinear in MATLAB. Then, the behaviors of the base isolation system and base-isolated buildings are evaluated for 45 different earthquake scenarios, which are categorized into three different groups with regard to the ratio of peak ground acceleration to peak ground velocity (PGA/PGV). The dissipation of energy by a base isolation system, which is induced by the earthquake, varies for three different ranges of the PGA/PGV ratio. Despite the fact that by increasing the number of stories, the effectiveness of the isolator system decreases, this paper shows the most important finding to be that the damage limitation requirement is kept below 1% according to Eurocode 8, which is the requirement for buildings at the upper limit on the inter-story drift ratio under seismic loading, and the inter-story drifts significantly decreases for the base-isolated buildings and even for high-rise buildings.