#### A quality of concrete: its compressive strength

A concrete with a compressive strength of 30 MPa after 28 days will require a crushing force of 60 tonnes in order to break a cylindrical test piece with a diameter of 16 cm. 1 MPa = kg/cm². The compressive strength of normal concrete varies between 25 and 50 MPa. Above this level, the term High Performance Concrete is used.