The 14th World Conference on Earthquake Engineering

The need for vulnerability assessment of urban scale building populations is of increasing interest due to the high seismic risk in densely populated areas around the world. Istanbul, Turkey, is one of the most intensively populated metropolises in the world in addition to being probably one of the most risky cities in terms of the expected seismic activity in the near future. In order to minimize the seismic risk of the city, instead of the method of evaluating every single building according to the existing code which failed immediately due to the source and time limitations, a wiser approach is being employed nowadays, namely, evaluating each building in the stock by using some simplified rapid or preliminary assessment techniques and focusing primarily on the “collapse vulnerable” structures. The proposed P25 Scoring Method is a preliminary assessment approach which is primarily based on calculation of area and inertia based ratios of structural members and infill walls as well as on observing and listing the most important structural parameters which affect the seismic response of a building. The method has been calibrated with 323 RC buildings from different seismic regions of Turkey that are subjected to different past earthquakes and experienced various levels of damages. The damage states and also performance levels of the analyzed case study buildings are found to be in good agreement with the proposed primary assessment technique. The paper includes the details of the method and the calibration results.