Seismic Risk Prioritization of Steel Buildings Using Fuzzy Inference System: A Case Study of School Buildings in Selected Regions of Tehran

The first and the most important step in preparation of seismic retrofit plan for existing buildings is the analysis of their vulnerability by conducting retrofit studies. However, most of the existing buildings in Tehran are in urgent need of retrofit studies due to reasons such as high seismicity, upgration of building and seismic codes, the abundance of old buildings and so on. In these studies, it is very important to identify the seismic status of the buildings which are in the first priority of seismic retrofit, especially the ones with public use like schools. A seismic risk prioritization technique for steel buildings is proposed in this paper, using a risk assessment hierarchical structure and fuzzy inference system. Afterward, this technique is applied in a case study, validating the results obtained for the steel buildings of the schools in Tehran. At the first of the prioritization process, the required information of the buildings is classified according to the designed hierarchical structure; Then, after quantification of the qualitative data and the fuzzification, the data are modeled, evaluated and defuzzificated based on the fuzzy inference system; This process is performed for all stages of the hierarchical structure to obtain the seismic risk parameter. After the qualification, this parameter indicates the risk of buildings and their requirement for retrofit or rehabilitation. The results that are distinguished by urban districts, determined the high-risk steel school buildings requiring retrofit studies and have shown the role of each effective parameters on the seismic risk of the buildings.