Rebound hammer test

Rebound hammer test is a non-destructive test used to assess the compressive strength of concrete. It is a simple and widely used method to determine the strength of concrete in the field, especially in situations where there is limited access or the use of other testing methods is not feasible.

In this test, a rebound hammer is used to strike the concrete surface, and the rebound of the hammer is measured and compared to a calibration curve to determine the compressive strength of the concrete. The rebound hammer consists of a spring-loaded hammer that is released to strike the concrete surface and a dial gauge that measures the rebound distance.

The principle behind the rebound hammer test is that the rebound of the hammer is related to the surface hardness and compressive strength of the concrete. The harder the concrete surface, the higher the rebound of the hammer, and the higher the compressive strength of the concrete.

Rebound hammer tests are commonly used on concrete surfaces that are at least 100mm thick, such as walls, columns, and beams. The test can be performed on both freshly poured and hardened concrete.

While the rebound hammer test is a useful method for assessing the compressive strength of concrete, it has limitations. The results of the test are affected by factors such as the moisture content, surface roughness, and age of the concrete, which can impact the accuracy of the test results. Therefore, it is important to follow standardized procedures and use appropriate calibration curves for the specific type of concrete being tested.