Concrete Mixes by Weight and Volume
A Table for Concrete Mixes by Weight in Kilograms
by Bag, and by Cubic Meter, for Various Strengths
We have had numerous requests for Concrete Mixes by Weight, by volume, and by mass. Here is a table that was released by the Cement and Concrete Institute for trial concrete Mixes by Weight from 10MPa to 40MPa. These are trial mixes and should be used to test your concrete before it is used in any construction work. Your “competent person” or project manager should always assess and approve any concrete work undertaken on your site.
The concrete mixes proportions in the table are by mass and volume, using different size stones, for different strengths of concrete. You must add water to the mixture until it becomes workable; you can judge this by eye. The difference between various types of cement and aggregates is not taken into account with these mixes. Make sure that the water is kept together with the mix and is not allowed to drain/run away as this could result in a weaker mix.
NOTE:
These proportions for concrete mixes by weight are based on the assumption that a CEM-type cement of strength class 32,5 will be used. The cement of strength class 42,5 or higher will give a stronger concrete but may be less economical. Cement with high extender contents (eg CEM 11/B or CEM 11) will develop strength more slowly and will require particular care with curing. Masonry cement complying with SABS ENV 413-1 should only be used with specialist advice.
The amount of water required is not given in the table. The mix should contain enough water to achieve the required consistency. Consistency may be assessed by eye or measured by carrying out a slump test (SABS Method 862-1: 1994)
A mix made according to this table, and to the required consistency, should be assessed for workability and stone content before being used on a large scale.
Quantities of materials per cubic meter of concrete are net. Allow for wastage when ordering – for instance 3% on cement and 10% on aggregates.
A standard bag of cement weighs 50kg so the equivalent quantities and weights are:
1 Bag cement = 50kg = 0.2 m3 (cubic metre)
Below is the nominal mix proportions (also referred to as the ratios of concrete mixes) for different strength categories, using a 19mm stone.
NB. Low would be average 15MPa, medium 25MPa and high 35MPa. This is a guide only and quantities must be adjusted for the final requirements and specified by a “competent person”.
In addition to the above:
Concrete mixes ratios by weight are a crucial aspect of concrete construction, determining the proportions of various ingredients needed to create a durable and structurally sound concrete mix. These ratios typically include cement, water, aggregate (sand and gravel), and sometimes additives or admixtures.
The most common concrete mixes ratios by weight are expressed as parts, where the weight of each component is represented in relation to the weight of cement, which is assigned a value of 1. For example, a common mix ratio for general-purpose concrete is 1:2:3, which means one part cement, two parts sand, and three parts aggregate. To calculate the actual weight of each component in this mix, you would use the weight of cement as the reference point and scale the weights of sand and aggregate accordingly.
The choice of concrete mixes ratios depends on the specific requirements of the project. For instance, higher-strength concrete may require more cement, while a mix for a concrete sidewalk might use less cement and more aggregate. Engineers and construction professionals carefully select ratios to meet structural, durability, and workability needs.
Water is another critical component, but its ratio can vary based on factors such as the desired slump (consistency) of the concrete and environmental conditions. Generally, water is kept to a minimum to maintain strength and durability, as excessive water can weaken the final product.
Additives and admixtures can also be incorporated to enhance specific properties of concrete, such as accelerating or retarding the curing process, improving workability, or reducing permeability.
Concrete mixes ratios by weight are a fundamental consideration in construction. They determine the strength, durability, and workability of concrete. Properly proportioned mixes are essential for ensuring that concrete structures meet design requirements and can withstand the test of time. Engineers and builders must carefully calculate and mix the components to create concrete that meets the unique demands of each project.
my house is 16m in length and 11 m wide. my concrete depth must be 75mm.How much cubic meter concrete do i need for the slab.
Hi for a double story house, which was calculated to be 14 m3 of concrete for foundation. Do I use the 50kg:100l:100l formule and what is the coverage? I am a new builder with a local team and I do not want to waste too much material. We have 12+12+16+16 ouside walls. Foundation to be concreted is .5 wide x .6 deep. Indside walls is 12+12+9 x .23wide x .5 deep. Thank you
Hello sir,
what is the compressive strength range for laterite bricks ?
what is the difference between concrete mix by volume and weight ? which one is better for concrete mix by volume ?
Good afternoon
Can you please help me. I need the weight of 1 cubic metre of concrete with a 25 Mpa strength
hi i would like to kno for a foundation for a single storey extension 3sides,5mx3mx5m, how much of sand stone & cement wud i need to do a 230 mm thick foundation x500withd.rgds denver
Good day
I want to double storey, of which in future I plan to convert the to teaching class of range of 100 to 400 people, I do not need to demolish the house before it can be converted, I would like to know the size of width, depth and thickness concrete,of foundation using 42.5 cement
The above (1 Bag cement = 50kg = 0.2 m3 (cubic metre)) is incorrect.
A bag of cement is 0.033m3 to 0.035m3
Hi Ben, It is the Ultimate tensile strength of the concrete, named after the French mathematitian Pascal (Pa) and the M = Mega hence MPa. You can read more here: https://en.wikipedia.org/wiki/Ultimate_tensile_strength
Hi Hari, 1cc of water = 1 gram so 1 Liter will = 1 Kg = cu vol 100mmx100mmx100mm = 1000cc. Find out what the volume is first then you will have the weight.
Hi Menas, The only way on site is to make a batch box and monitor the people doing the mixing closely. The other factor that come into the calculation is the stone size and the dampness of the sand. So the mixing becomes an imprecise science. If you are worried it might be better to use a ready mix where you have some recourse if anything should fail.
How can site concrete mix design be made more reliable, even against readymix concrete from batching plant?
What does Mpa stand for
how to calculated the weight
of water
We have a very inexpensive handbook that will give you all the info you need about concrete and mortar.
We have a very inexpensive guide to mortar and concrete
what is the correct ratio mix 25mpa 1 shovel cement how many shovels premix do i need
What strength of concrete do I need to threw for a slab to be used as parking for motor vehicles, small truck up to 4 tons and forklifts with a capacity of 5 tons. Slab will also be used as a loading bay.
Good morning Janek
Many thanks for your help and advice. It is really appreciated. I’ll give it a bash and see how we do. This is a very helpful website. Thanks again.
Kind regards.
Hi Laurence, Ideally to get your 1.2³ m the number of bags will be .841³m with .84³m each sand and stone in theory. It is best to always mix a little extra as there will always be shrinkage and some waste. So your ratio of 9 bags to 1³m sand and 1³m stone will fine be for the strength and quantity you need.
Good day to you
I am throwing a slab with a required strength of 25 MPA. The area is 16m² at a required thickness of 75mm, which calculates to 1.2 m³ of concrete.
The above tables only gives me the ratio mix for 1m³, and I am required to have slightly more.
How much more cement, sand & stone will I require to complete the job satisfactorily? I will be using the 19mm stone. Would it be safe to use say 9 bags of cement to 1m³ sand and 1m³ of stone?
I will be grateful if you could assist me with this calculation.
Many thanks for the helpful website.
Regards.
thank u for yrs. help
Sorry I can’t help!
pls tell me the process of estimating of the building and roads
Hi Roger, You will need 75sq m X .1 = 7.5 cubic meters of concrete. The tables on this page “concrete-mixes-by-weight” will give you the amounts that you will need.
Greetings, I want to do 75 s/m concrete floor, @100mm thick, how much cement, sand and stone will I need for this job. Regards
You have to work in batches Asuquo
Thank you,but how can i reduce the amount of the materials so that it can enter or contain in a 56 litres mixer.