Types of Concrete Mix Ratio Design and their Strengths
Concrete mix is known as mixing cement with sand, stone/aggregates and water into a paste form that can be used to bind the building materials together.
The right proportion of cement, sand, stones or aggregates mixing determines the concrete max strength. There is some variety of concrete available in the market based on these ratios like M10, M20, M30, M35.But people does not know differences of M10 or M20.
?Mix? is known as ?M?. Concrete with designated proportions of cement, sand and aggregate is represented as mix. And the number following represents the compressive strength of that concrete mix in N/mm2 after 28 days is determined by number designated after ?M?.
The concrete mix of M20 grade will determine 20 N/mm2 of compressive strength after 28 days.
Table of Concrete Mix Ratio
The table below shows variety of concrete mix design with their respective requirement ratios of cement, sand and aggregates.
Concrete Grades |
Concrete mix design of various ratio |
M5 |
1:5:10 |
M7.5 |
1:4:8 |
M10 |
1:3:6 |
M15 |
1:2:4 |
M20 |
1:1.5:3 |
M25 |
1:1:2 |
M30 |
1:0.75:1.5 |
M35 |
1:0.5:1 |
M40 |
1:0.25:0.5 |
As you can notice in the above table, sand volume is always kept half of that of aggregates in these standard mix designs.
Use buckets or some standard cubes in the project helps to measure and maintain these ratios. During the entire project, engineer/supervisor has to inspect and enforce to each and every concrete mix preparation in a consistency way.
Ratio of Water Content of Concrete Mix
The strength & workability of concrete is fundamentally determined by water content. The more amount of water, the workability of concrete (more fluid) will be higher.
But it decreases the concrete strength. If you keep low water, water workability will also decrease and it will be difficult to place such concrete in the structure.
Same concrete volume for various grades of concrete may be varied by the different amount of water. So engineers or supervisor must notice the right balance of concrete mixing must find the right balance in the construction site.
Conclusion
In concrete mix there are some steps and procedures like proper water mix, Portland cement, sand, and stone aggregates. We also found during the process of mixing that more or less water makes the concrete more workable or less workable. The slump test is perfect for this kind of mix.