Recent advances on non-destructive evaluation of concrete compression strength

The evaluation of structural performance of existing concrete structures, built according to standards and materials quite different to those available today, requires procedures and methods able to cover lack of data about mechanical material properties and reinforcement detailing. This issue is more relevant where seismic zones are concerned and structural strengthening is needed to prevent failures due to earthquakes. Recent seismic codes give relevance to procedure and methods to establish the performance levels of existing structures. To this end detailed inspections and testing on materials are required. As a consequence non-destructive testing (NDT) can be used in conjunction with destructive testing (DT) by a representative correlation between DT and NDT. The aim of this study is to verify the accuracy of some of the most reliable and employed formulations available in literature between measured parameters, i.e., rebound index (RI) and ultrasonic pulse velocity (UPV), and compressive strength (SonReb Method).