Akademik Veri Yönetim Sistemi
JOURNAL OF POLYTECHNIC-POLITEKNIK DERGISI, cilt.25, sa.2, ss.655-665, 2022 (ESCI, TRDizin)
Lead rubber bearings (LRBs) are among the most commonly used seismic isolation bearing types due to their high energy dissipation capacity. However, the experimental studies reveal that the temperature rise occurring under cyclic loads in the lead core, causes a deterioration in the characteristic strength by decreasing the yield strength of the lead, and it is important to consider this effect. In seismically isolated buildings, in addition to the isolation system, the superstructure also has a degree of energy dissipation capacity thanks to its inherent damping. It is seen that different damping ratios are used in the designs of such structures and research studies dealing with these structures. In this study, the change in the temperature-dependent behavior of seismically isolated buildings is investigated in cases where (i) superstructure damping is taken as 5% similar to fixed base reinforced concrete buildings, (ii) superstructure damping is taken as a smaller value such as 2%, and (iii) superstructure damping is completely neglected. A seismically isolated reinforced concrete building is modeled in the OpenSees program, considering the effect of the lead core heating on the characteristic strength and responses such as floor accelerations, temperature increase in the lead core, bearing shear forces and displacements obtained from nonlinear time history analyses are investigated. The results obtained showed that especially the floor accelerations can vary significantly and the floor accelerations obtained with different superstructure damping ratios can be in different limit ranges.