Concrete Grades,Types, Ingredients, Properties and Strength

Concrete is a construction material composed of cement, fine aggregates (sand) and coarse aggregates mixed with water which hardens with time. Concrete Grades,Types, Ingredients, Properties and Strength details you can find here.

Concrete Grades

Grades of concrete are defined by the strength and composition of the concrete, and the minimum strength the concrete should have following 28 days of initial construction. The grade of concrete is understood in measurements of MPa, where M stands for mix and the MPa denotes the overall strength.

Grade of Concrete        Mix Ratio      Compressive strength in 28 days

M5	1 : 5 : 10	5 MPa
M7.5	1 : 4 : 8	7.5 MPa
M10	1 : 3 : 6	10 MPa
M15	1 : 2 : 4	15 MPa
M20	1 : 1.5 : 3	20 MPa
Standard Grade of Concrete
M25	1 : 1 : 2	25 MPa
M30	Design Mix	30 MPa
M35	Design Mix	35 MPa
M40	Design Mix	40 MPa
M45	Design Mix	45 MPa
High Strength Concrete Grades
M50	Design Mix	50 MPa
M55	Design Mix	55 MPa
M60	Design Mix	60 MPa
M65	Design Mix	65 MPa	i
M70	Design Mix	70 MPa

Concrete pouring

Type of Concrete

1. Normal Strength Concrete
2. Plain or Ordinary Concrete
3. Reinforced Concrete
4. Prestressed Concrete
5. Precast Concrete
6. Light – Weight Concrete
7. High-Density Concrete
8. Air Entrained Concrete
9. Ready Mix Concrete
10. Polymer Concrete
    1. Polymer concrete
    2. Polymer cement concrete
    3. Polymer impregnated concrete
11. High-Strength Concrete
12. High-Performance Concrete
13. Self – Consolidated Concrete
14. Shotcrete Concrete
15. Pervious Concrete
16. Vacuum Concrete
17. Pumped Concrete
18. Stamped Concrete
19. Limecrete
20. Asphalt Concrete
21. Roller Compacted Concrete
22. Rapid Strength Concrete
23. Glass Concrete

Concrete Ingredients

1. Cement

2. Coarse aggregate

3. Fine aggregate

4. Water

1. Cement 

The cement and water form a paste that coats the aggregate and sand in the mix. The paste hardens and binds the aggregates and sand together.

Portland cement is the commonly used type of cement for production of concrete.

2. Coarse aggregate

Gravel or crushed stone is the coarse aggregate.

3. Fine aggregate

Sand is the fine aggregate.

4. Water

Water is needed to chemically react with the cement (hydration) and to provide work-ability of concrete. The amount of water in the mix compared with the amount of cement is called the water/cement ratio. The lower the w/c ratio, the stronger the concrete. (higher strength, less permeability)  

Concrete Properties

1. Concrete gain strength in presence of water, but most of the materials rust or decay when they are wet.
2. Concrete can be moulded to any shape at normal temperature and pressure.
3. Concrete resist attack of insects.
4. Concrete is fire and sound proof.
5. Strength of concrete is high.
6. Strength of concrete can be further increased by reinforcement, prestressing etc.
7. Concrete becomes stronger with age.
8. Frequent repairs, painting etc not required for concrete.
9. It is economical and strong compared to other construction materials.
10.Concrete can be pumped to any difficult places.
11.The material for concrete is easily available.
12.Concrete can be used to apply modern construction techniques for modern construction works.

Compressive Strength of Concrete

Compressive strength is the ability of material or structure to carry the loads on its surface without any crack or deflection. A material under compression tends to reduce the size, while in tension, size elongates.

Compressive Strength of Concrete at Various Ages

The strength of concrete increases with age. Table shows the strength of concrete at different ages in comparison with the strength at 28 days after casting.

Age	Strength percent
1 day	16%
3 days	40%
7 days	65%
14 days	90%
28 days	99%

Compressive Strength of Concrete at 7 and 28 Days

Grade of Concrete	Minimum compressive strength N/mm2 at 7 days	Specified characteristic compressive strength (N/mm2) at 28 days
M15	10	15
M20	13.5	20
M25	17	25
M30	20	30
M35	23.5	35
M40	27	40
M45	30	45

Concrete Mix Design

Concrete Mix Design is all about achieving target strength, water cement ratio and perfect proportions of Cement, Sand and Aggregate to produce a good concrete to achieve its target strength.




Related Articles :

M30 Grade of Concrete Mix Design Calculation Procedure

Concrete Mix Design Calculation for M40, M60 as per IS Code

Concrete Test on Green or Fresh Concrete and Hardened Concrete