Evaluation of rapid seismic safety assessment methods on a substandard reinforced concrete building stock in Istanbul

Exposure, hazard and vulnerability are the components of seismic risk, and knowledge on the vulnerability of the existing buildings is vital to properly assess their risks in seismically active regions. Unfortunately, it is not easy to assess the vulnerability of individual buildings realistically in large building stocks, particularly for regions where the buildings do not comply with the current and previous code regulations. In this study, for assessing the accuracy, applicability and cost-effectiveness of available rapid seismic safety assessment procedures for individual reinforced concrete buildings in huge building stocks, five second stage and three rapid visual screening methods are examined in a comparative manner. For this purpose, these eight methods are used to assess the seismic risks of actual service buildings of Istanbul Metropolitan Municipality, which had been previously evaluated by the third-level detailed code-based seismic performance assessment procedures. Furthermore, comprehensive site works have been conducted to compute the average time required for collecting data on each parameter necessary to use the investigated rapid assessment methods. Finally, the most cost and time-effective, and highly accurate rapid assessment method among the examined ones is selected to be applied to a vast amount of structures in Istanbul to prioritize them in terms of their seismic risks and plan the large volume mitigation interventions through a realistic and efficient approach.