Schmidt Hammer/Rebound Hammer

Rebound Hammer Test

The Rebound Hammer Test is a non-destructive test of compressive strength of concrete conducted following the ASTM C805 standard.

The compressive strength of concrete is a crucial value in structural assessment as it is the main variable that can affect the load carrying capacity of reinforced concrete structures.

The mechanism inside the rebound hammer is the spring-loaded mass which will be triggered when the plunger is pressed against the concrete. The impact energy from the spring-loaded mass will be transferred into the plunger to the concrete surface, and the reflection of impact energy (rebound) will be indicated by a “rebound number” shown at the scale on the side of the hammer unit. The interpretation of concrete compressive strength is conducted by using the relationship of the rebound number and the compressive strength.The higher rebound number (higher reflection of impact energy) implies the higher compressive strength of concrete.

The test will not leave any damage on the surface of structural concrete, and it can be done quickly and at a low cost suitable for large testing areas.

The Rebound Hammer Test can also be conducted in conjunction with the Compressive Strength Test for the Cored Samples for more accurate test data.