How to improve the quality of concrete assessment by combining several NDT measurements

RILEM TC INR-207 is devoted to the combination of non destructive techniques to improve the assessment of reinforced concrete. Several practical key applications have been selected, corresponding to the assessment of material condition, to the detection of defects or to the identification of an unknown geometry. For each application, the problem is analyzed from the point of view of added-value brought by combination. This paper explains what is the challenge when quantification is the main objective, and details what is done by TC members in a specific application, that of concrete strength assessment.