سال انتشار: ۱۳۹۱

محل انتشار: نهمین کنگره بین المللی مهندسی عمران

تعداد صفحات: ۷

نویسنده(ها):

Beytollah Taromi – Ms Student, Zanjan University, Zanjan, Iran
Kiarash Nasserasadi – Assistant Professor, Department of Civil Engineering, Zanjan University, Zanjan, Iran
Asghar VataniOskouei – Assistant Professor, Department of Civil Engineering, Shahid Rajaee University,Tehran, Iran

چکیده:

Recently the experience of recent near fault earthquakes such as Chi-Chi, Kobe and Tabas earthquakes have shown that the structures are more vulnerable in the near source earthquakes. This has also shown in many studies. The main reason for that is due to a strong and long period velocity pulse which generates in the near-field (NF) earthquakes. Base isolation systems are one of the methods for reducing the damage and vulnerable in the near source earthquakes, seismic isolation system increase period vibration of structures which reduce seismic force and the amount of energy transferred into the structure. In this paper, a parametric study has been carried out to study the behavior of based isolated concrete buildings in the near source earthquakes. One base isolated concrete building with 7 stories is considered. The variation of top floor absolute acceleration, base shear and bearing displacement of the isolated building is plotted under different isolator parameters such as bearing yield strength and post yield stiffness ratio. The comparison of results indicated that for low values of the bearing yield strength and post yield stiffness ratio there is significant displacement in the lead- rubber bearing(LRB) under near-fault motions. In addition the increase of isolation period causes the base shear and floor acceleration reduced, but bearing displacement increases very much