SON-REB method

The SONREB method is based on the combination of the results obtained, in the same test areas, from tests with rebound hammer and ultrasonic tests, correlating the rebound index (REBound) and the velocity of ultrasonic waves (SONic), with the compressive strength of concrete. The correlation is done through an appropriate calibration of the relationship that links these three quantities by means of statistical regression of the experimental values. The SONREB method aims at compensate the inaccuracies of the two non-destructive methods used, the moisture content causing the rebound index to be underestimated and the ultrasonic speed to be overestimated, and the age of the concrete increasing the rebound index while decreasing the ultrasonic speed. By carrying out compression tests on samples taken in the same points where the non-destructive tests are carried out, an increased correlation accuracy is obtained. In case no direct compression data are available for the tested concrete, literature correlation curves are employed. Reference standards: UNI EN 12504-4:2021; UNI EN 12504-2:2021.