Relating repair-strengthening or demolition-reconstruction decisions for existing structures of different usage purposes and building classes to public construction costs in typical functions

The decision to demolish and reconstruct or strengthen structurally vulnerable buildings before and after an earthquake depends on numerous parameters, one of which is the realistic estimation of reconstruction costs. In this study, a comprehensive literature review was conducted on the vulnerability rates of structures, and potential structural damage ratios, as well as their impacts on humans and the environment, were examined using the Hazus method published by FEMA. Studies that account for local conditions were also analyzed, and the damage-loss probability and ratio estimation method employed in this research was explained in detail. The study investigates the processes of annual estimation of approximate building and construction costs in Turkey and the determination of building costs published by Ministries. The changes in building construction costs between 1995 and 2024 were analyzed. For this purpose, the relevant data were compiled, converted based on exchange rates for the corresponding years, normalized to today's exchange rates (USD and TL), and statistically analyzed. The dispersions of these values were identified, and proposed values were evaluated for three different confidence levels. As case studies, potential damage and losses were examined for a steel industrial structure and a reinforced concrete residential structure, and the justifications for repair-strengthening versus demolition-reconstruction decisions were presented. The study derives results by incorporating cost changes in the construction sector with the building lifecycle, considering depreciation as a basis. It demonstrates the use of predictive tools, specifically the Erdemli Damage/Loss Estimation Analysis (ERD-HKTA) method, in decision-making processes for reconstruction or strengthening in various functional structures.