On-site strength assessment of limestone based concrete slabs by combining non-destructive techniques

An experimental program is conducted on concrete slabs of different strength classes intended for various exposure classes, based on a limestone aggregate matrix, which is typically used for Belgian applications. Besides destructive core drilling and testing, the following non-destructive techniques were selected for this study: the rebound hammer, the ultrasonic pulse velocity tester, the Wenner probe for concrete resistivity and the Windsor probe (semi-destructive). Best fit correlations between the output of these different techniques and the destructively determined compressive strength were established. By means of multiple linear regression analysis, different non-destructive techniques were combined for assessment of strength of limestone based concrete.