Seismic reliability analysis of reinforced-concrete hospital building with base isolation

When an earthquake occurs in a region, it causes structural damages to buildings. Retrofitting these damaged structures before earthquakes to happen reduces the potential hazards and minimizes future casualties. In this paper, the seismic assessment of Reinforced Concrete (RC) structure inadequately to withstand seismic loads due to changing demands, and their retrofitting is studied. After a brief introduction of seismic retrofit described for an existing structure, methods of assessing the seismic vulnerability of existing building is presented. To show the effect of the selected retrofit approach on the seismic behavior of RC buildings, an existing hospital building was selected as the case study. Since the use and occupancy of the selected RC building designed as a residential building had changed, a seismic assessment was carried out using Opensees software to show whether the building needs seismic retrofit or not. For this purpose, nonlinear dynamic analysis of hospital structures under 7 earthquake records concerning Type 2 soil was carried out based on Iranian seismic codes. Besides, to consider uncertainties and structural reliability analysis, 27 earthquake records have been used by the Monte Carlo Sampling (MCS), which results showed that the building needs seismic retrofit because of the increasing demands. In the following, the retrofit approach, which contains using Lead Rubber Bearing (LRB), was performed based on Iranian codes. It is concluded that using this technique of retrofitting and using the reliability analysis method can have a new approach as well as an effective role in improving the seismic behavior of structures.

Keywords:

Reliability analysis , Seismic Assessment , Retrofitting , Lead Rubber Bearing , Monte Carlo Simulation