Abstract:

Because of the large displacements at isolation level of a base isolated building, the stability problem arises. Seismic code provisions limit the base isolation technique, in practice, to buildings in the low – to medium rise range. In this study, an earthquake resistant design concept is suggested which enable the base isolation technique is used in low – to medium rise buildings as well as high rise ones. Instead of classical base isolation technique in which the structural flexibility is concentrated in the isolation level at the base of the building, the distributed flexibility along the height of the building is proposed. How the distributed structural flexibility affects the seismic isolation performance of the building is investigated. Reinforced concrete building models which are regular and irregular in plan, and have various isolation parameters, supporting conditions, number of stories (varying 1 to 20) is prepared. The seismic response of new isolation concept building models subjected to N – S component of 1999 Golcuk Earthquake (Yarımca-Petkim) input is evaluated and compared with the responses of the corresponding fixed base and conventional base isolated models. The results demonstrate that using isolators between storeys of superstructure improves seismic response in 12 storey model which is regular in plan and in 12 and 16 storey model which are irregular in plan.

Keywords: