Concrete mix grades
What are different types of concrete mix grades, their strength & their uses?
In concrete mix grades “M” presents concrete mix design ratio and the number after “M” presents MPa or N/mm2 compressive strength of concrete. For example M10, M15, M20, M25 concrete mix grades.
There are different types of concrete mix grades in civil engineering according to their need and use.
Some of them are standard and pre designed & calculated but sometimes in special occasion need based concrete mix designs are used. There uses are depended upon their strength. According to nature of project we go for a ready mix concrete and sometimes we mix on site.
5N/mm2 means that one mm2 area of concrete cube of 150mm can resist 5N or 5MPa compressive load after curing the 28 days. It can be converted into PSi (by multiplying with 145).
IMPORTANT! C10, C15, C20, C25 etc are British/European standard of “Concrete strength class”.
Below the chart is given, there’s the concrete mix grades, their strength and their uses are mentioned.
Read also types of concrete.
Concrete mix ratio and grade table:
Concrete GradeMix Ratio (C:S:A) and Compressive Strength (MPa)
M51:5:10 725psi
M7.5 1:4:8 1087psi
M10 1:3:6 1450psi
M15 1:2:4 2175psi
M20 1:1.5:3 2900psi
M25 1:1:2 3625psi
M30 4350psi
M40 5800psi
M50 7250psi
M60 8700psi High Strength Concretes
M70 10150psi
M80 11603psi
Concrete mix grades and strength
M5 concrete mix:
M5 (1:5:10) is lean concrete mix which can bear 5 newton load/pressure on per square millimeter area or 725 pounds on per square inch.
It is used in footing/foundations bed to provide smooth and plain surface for foundation and to separate the direct interaction of foundation with surface.
M7.5 concrete mix:
M7.5 (1:4:8) is also a lean concrete mix which is used in foundation to provide plain surface and to make a disruption between footing and the ground surface.
It is used where there is a little more strength is needed as compare to M5 mix.
M10 concrete mix strength:
Concrete mix From M10 (1:3:6) is ordinary concrete. It bear less load than compare to M15. M10 has 10 N/mm2 or 1450 Psi compressive strength. It is use in plinth beams, slabs, R.C.C walls, road pavements etc.
M15 concrete mix strength:
M15 has concrete mix ratio (1:2:4) and it is most commonly use concrete mix because of its compressive strength and economical conditions in ordinary concrete mix section.
M15 has 15 Newton compressive strength per square millimeter or 2175 Psi. M15 concrete is use in Building columns, beams, slab, for plinth beam, bridge piers, pavements almost everywhere generally.
M20 and M25 concrete mix ratio:
What is M20/M25 concrete mix ratio? M20 concrete mix ratio is (1:1.5:3) respectively. M20 has compressive strength of 20 N/mm2 (MPa) or 2900 Psi
M25 concrete mix ratio is (1:1:2) and M25 has 25 N/mm2 or 3625 Psi compressive strength.
Concrete mix grades ratio
Read also ready mix concrete & precast concrete.
M30, M40, M50 conc mix:
M30 to M50 Concrete mix are Standard mix. It is mixed according to designed. That have really high compressive strength.
That are used in Septic tanks, Dams, Barrages, Flyovers, Bridges columns etc. That have as high compressive strength of 4350 psi to 7250 psi.
M60, M70, M80 conc mix:
M60 to M80 concrete mix are high strength concrete and designed mix. That have 8700 psi to 11603 psi compressive strength. That are used in special occasions.
which concrete grade is used in burj khalifa? In construction of burj khalifa M50 to M80 (high strength) concrete mix grade is used.
Beside compressive strentgh high strength concrete mix grade also have resistance against chemical erosion, acid attacks etc.
High strength concrete mix grade is used in chemical labs, nuclear reactors, nuclear weapon ware houses.
Source: civilmanage.com