Determination of Structural Fragility Curves of Various Building Types for Seismic Vulnerability Assessment in the Sarpol-e Zahab City

Seismic vulnerability assessment helps to estimate the extent and the probability of damage to buildings due to the potential earthquake hazard. Determination of structural fragility curves of buildings is one of the most important steps in seismic vulnerability assessment. The fragility curve predicts the probability of exceeding specific damage states for a seismic intensity parameter. This paper is focused on the development of structural fragility curves for different building types in the Sarpol-e Zahab city. For this purpose, a reconnaissance survey was conducted after the Sarpol-e Zahab earthquake of November 12, 2017 to identify the damage state of various buildings based on the HAZUS Methodology. Then, the improved displacement coefficient method implemented in the SELENA software was used for expressing building loss probabilities. In order to find out which level of the seismic design can be used in defining the fragility curves, different weights were considered to apply to the HAZUS fragility curves of high, moderate, low and pre-code to be used in the logic tree method. Finally, the mean and standard deviation values were introduced for the construction of fragility curves with the lognormal distribution