Determination of Calibration Factor of Rebound Hammer as per IS 516 (Part 5/Sec 4) : 2020

In this video , we will discuss in detail for establishing a correlation between rebound hammer and concrete strength by concrete cube. The most satisfactory way of establishing a correlation between compressive strength of concrete and its rebound number is to measure both the properties simultaneously on concrete cubes.
The general correlation can be derived from concrete cubes used in smaller projects in a region with similar materials including cement type and the same shall be repeated every year. For bigger projects at least three cubes each for three different concrete grades shall be cast and tested for establishing the correlation. Cube specimens should be wet cured for 27 days and they should be removed from wet storage and kept in the laboratory atmosphere for about 24 h before testing.