NDT PROTOCOLS FOR THE DIAGNOSTICS AND MAINTENANCE OF EARLY REINFORCED CONCRETE STRUCTURES: A CASE STUDY

摘要

The research work presented is focused on the diagnostic and rehabilitation of historical structures in reinforced concrete, and has been carried out within a scientific collaboration program with the Railway Company "Ferrovie Appulo Lucane", aimed at monitoring the maintenance state of their architectural and infrastructural patrimony. In particular, the case of the Viaduct of Corso Italia in Bari is illustrated. The objectives of the research are the detailed characterization of the structure through the application of a complete protocol of diagnostic, and the elaboration of correlation curves on the base of experimental data. In the future, this will allow the control of the actual structural conditions on the basis of only non destructive testing, in a short time and with reduced cost and intrusion in the structure. After a detailed survey of the deterioration, a program of ND testing has been carried out: Chemical and physical characterization of the concrete mixture; Appraisal of the corrosion level for reinforcement bars; Appraisal of in situ properties and homogeneity for the concrete (by means of rebound hammer and ultrasonic testing, extraction of samples in order to provide the correlation curves). By processing the data correlation curves have been obtained that will be used, in the future, the monitoring of the structure by only using ND investigations and reducing length, cost and invasiveness of inspections.