GRADE OF CONCRETE

GRADE OF CONCRETE

               Concrete is generally graded according to its compressive strength. the various grades of concrete as stipulated i IS:1343-1980 are given in the table. In the designation of concrete mix, the letter M refers to the mix and the number to the specified characteristic strength of 150 mm work cubes at 28 days, expressed in MPa ( N/mm2). The concrete of grades M5 and M7..5 is suitable for lean concrete based, simple foundations, foundations for masonry walls and other simple or temporary reinforced concrete construction for masonry not be designed. The concrete grades lower than M15 is not suitable for reinforced concrete works and grades of concrete lower than M30 are not to be used in the prestressed concrete works.

GRADE OF CONCRETE is of three types.

• Ordinary Concrete
• Standard Concrete
• High Strength Concrete

Ordinary Concrete

GROUP	Ordinary concrete			Standard concrete							High Strength Concrete
GRADE DESIGNATION	M 10	M 15	M 20	M 25	M 30	M 35	M 40	M 45	M 50	M 55	M 60	M 65	M 70	M 75	M 80
Specified characteristic strength at 28 days, MPs	10	15	20	25	30	35	40	45	50	55	60	65	70	75	80