Different types of grades of concrete as per 456 : 2000 standard
This construction video tutorial from learning technology demonstrates the grades of concrete on the basis of IS 456 : 2000 standard. As per this standard the grades are categorized in three groups like ordinary concrete, standard concrete and high strength concrete. Here grades range from M10 to M80.
M10, M15 and M20 belong to Ordinary Concrete. M25, M30, M35, M40, M45, M50, M55 belong to Standard Concrete. M60, M65, M70, M75 and M80 belong to High Strength Concrete (HSC).
Here m denotes mix and number denotes characteristic compressive strength of 150 mm cube at 28 days in N/mm2 (Newton per millimeter square). It means if you take compressive test of a cube having dimensions 150 x 150 x 150 mm for 28 days, the value obtained is 10 N/mm2.
All these concrete grades are suitably for PCC work i.e. plain cement concrete work where rebar is not used.
Standard Concrete is generally used in 10 storied and higher buildings and super structures.
High strength concrete is mostly used for designing heavy structures.