Seismic performance evaluation of existing building using Seismic Index method

Abstract

Indonesia has frequently suffered major damaging earthquakes over the past 50 years. There are thousands of buildings in earthquakeprone regions that require seismic evaluation and rehabilitation. This paper describes a study about the seismic evaluation of existing buildings using seismic index method based on a Japanese standard. The basic seismic index is calculated based on the criteria of strength and ductility. Two existing buildings have been evaluated in this research. The first building consists of five stories and the second one has four. The seismic index of the structure has a different value for each story. The minimum seismic index occurs on the ground floor, and the index increases as the number of stories increase. The top floor has the maximum seismic index of all stories. The structure’s seismic safety shall be judged if the seismic index (Is) is greater than the seismic demand index (Iso). As a result of the evaluation, buildings A, and B are in an unsatisfactory condition. Especially for the three lower floors of both of buildings. It is also confirmed by drift angle that they exceed the required limit. To sum up, evaluation by using Japanese standards can be applied to building conditions in Indonesia.