Estimation of repair costs for RC and masonry residential buildings based on damage data collected by post-earthquake visual inspection

In the immediate post-earthquake, the safety conditions of buildings are commonly evaluated by field visual inspections. Then, a second phase involves the design of repair interventions and the relevant funding requests to the government or to insurance companies. The paper discusses the data related to the 2009 L’Aquila earthquake, focusing on the empirical damage and relevant Actual Repair Costs (ARC) of damaged residential buildings derived from requests for funding presented by practitioners engaged by owners in the reconstruction process. In particular, the data collected from a set of 2500 residential Reinforced Concrete (RC) and masonry buildings are presented focussing on the construction age, number of storeys, damage extent on structural components and ARC. A damage index for each building component has been computed according to data collected by field inspections and the relationship between damage index and different classes of buildings is herein outlined. Then, a correlation between the empirical damage and ARC is determined by means of a regression analysis. The proposed relationship between empirical damage and ARC may drive decision makers, in the immediate post-earthquake, to make preliminary estimates of the repair costs, only based on quick surveys on residential buildings. The relationship may also be used as a tool to figure out repair costs based on damage scenarios.