ZC3-A Portable Concrete Rebound Hammer Tester, also known as a Schmidt hammer or Swiss hammer. It's a non-destructive testing (NDT) instrument used to estimate the compressive strength and assess the quality of hardened concrete.
Helpful information:
It measures the rebound number (R-value) of concrete by impacting the surface with a steel hammer.
The rebound number correlates to the surface hardness and, indirectly, to the concrete's compressive strength.
It can help identify areas of inconsistent concrete quality, damage from freezing or fire, and areas needing further evaluation.
Factors like the smoothness of the concrete surface can affect the test results.