Application of the Combined Method for Evaluating the .
The Rebound Hammer strength test, being a non-destructive test, has its advantages of preserving integrity of sample. Besides, the test is relative simple, economical and versatile compared to conventional crushing tests. The method is widely used for testing concretes manufacturers of such rebound hammers usually provide calibrated curves showing the relation of compressive strength .The temperature history is used to calculate a quantity called the maturity index. . development of compressive strength, and other mechanical properties of concrete, under . need for standards on estimating in-place concrete strength during.