Often, existing concrete structures will need to be examined and tested to ensure the concrete remains of adequate strength and durability. Rebound hammer surveys can be conducted to provide a rough estimate of concrete strength, where it is not possible to determine this by more accurate means such as core extraction and testing.
The test involves using a special rebound hammer, which measures the recoil of a piston against the concrete surface when a standard force is applied. This recoil can then be correlated approximately to concrete strength.
Rebound Hammer is used for-
- assessing the likely compressive strength of concrete with the help of suitable correlations between rebound index and compressive strength,
- assessing the uniformity of concrete, iii) assessing the quality of the concrete in relation to standard requirements, and iv) assessing the quality of one element of concrete in relation to another.
- It consist of a spring controlled mass that slides on a plunger within a Tubular spring
- Fixed load required-7 N/mm²
- Impact energy of hammar-2.2 N.M
- 150 mm Specimen used for calibration