PSI - Issue 64

Francesco Calabrò et al. / Procedia Structural Integrity 64 (2024) 1759–1766 Francesco Calabrò, Giovanna E. Minniti, Antonino Fotia, Raffaele Pucinotti / Structural Integrity Procedia 00 (2019) 000 – 000

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Keywords: Authomated data acquisition; Cost estimation; Structural Degradation;

1. Introduction The historical building heritage made of reinforced concrete presents a series of peculiarities compared to the heritage of eras preceding the period of the Industrial Revolution. The life cycle of these buildings is strongly influenced by the characteristics of the materials with which they are made. On the other hand, the choice to proceed with their recovery does not respond to judgments of exclusively financial convenience. From this point of view, in fact, it would often be more convenient to demolish the buildings and replace them with buildings designed and built from scratch. To make an informed choice between recovery or demolition and reconstruction, the decision maker needs to have sufficiently detailed information on the economic implications of the two choices. The convenience of recovery, however, lies in two types of further considerations, deriving from the idea of sustainability of development. First of all, the considerations that drive their recovery are of a cultural nature, connected with the values that they transmit to future generations. The other type of considerations is of an environmental nature, connected with the principles dictated by the circular economy: it is the revolution underway in the economic field, which pushes us to move from the linear economy model, based on the princip les of "take, produce, dispose” to the regenerative model, based on the so - called “4 Rs”: “Reduce, Reuse, Recycle, Recover”. From this perspective, it is clear that the existing building heritage incorporates a capital of energy and raw materials which must be valorised through recovery. 2. The Construction Cost in the recovery interventions The estimate of the costs for the recovery of the existing building heritage does not present significant conceptual difficulties in the executive planning phase, relying on a long-established analytical approach, which sees the metric calculation as the tool for controlling the construction cost, starting from the individual processes, the result of which then flows into the economic framework, which allows the production cost to be estimated. A profoundly different matter, however, is that relating to the estimation of costs in the feasibility project phase, introduced by the Public Contracts Code with Legislative Decree 18 April 2016, n. 50, confirmed by Legislative Decree 31 March 2023, n. 36, which instead eliminated the defined planning level. While the executive project provides all the information necessary to process the estimated metric calculation, therefore proceeding in an analytical manner, at the feasibility project level the available information allows you to use exclusively a synthetic estimation procedure. The sources that can be used to identify the parametric values to be used are essentially the typological price lists generally published by the Regions or professional associations. These typological price lists are developed by examining the final costs of works already completed. This procedure undoubtedly has the advantage of referring to real, historically and geographically determined costs. First of all, it must be clarified that the values reported in the typological price lists refer to construction costs which, as is known, constitute only one of the items in the more general production cost formula: C P = C A + C I + C R + C C + (O U + C CO ) + S T + I M + C AS + S G + S C + I where: C A = Cost of the building area or building to be renovated C I = Area qualification costs C R = Costs for surveys, assessments and investigations C C = Construction cost