Cement is a mixture of aggregates and paste. The paste is usually made from cement and water, while the aggregates can be either fine or coarse.
There are two types of concrete that I would want to mention. First, we have fresh concrete that should possess the desired workability. Then, we have hardened concrete that should possess the desired strength and durability.
There is precisely how much cement, water, and aggregate should be used to get a good mixture. Usually, the concrete mix is made from 10 to 15 per cent cement, 15 to 20 per cent water, and 60 to 75 per cent aggregate. It is crucial to design the mix properly if we want to get a properly designed mixture.
What goes into a concrete mix
Making concrete mix is not as easy as most people think. There needs to be the right amount of water, cement, gravel, and sand, with a hint of air as well, to get a mixture that will be strong and durable enough. Proportioning the ingredients properly and mixing them well is also very important.
To understand the mix ratios and mix design, we will need to discuss the separate materials that go in the mix.
People generally usually use Portland type A cement in the concrete mix. This type of cement has a light grey colour and is suitable for most types of concrete jobs. It comes packed in 40-kilogram bags or larger ones, but it has a limited storage life. So, make sure that you buy some only when you are planning on using them. If you leave it to sit for a long time, it will become lumpy and largely unusable.
The sand that is used in a concrete mix should not have any clay, salts, or other organic materials. If the sand is right in clay content, it will produce low-quality concrete.
River Gravel/Crushed Stone/Blue Metal
When using coarse aggregate for a concrete mix (which is different from exposed aggregate), you should decide between crushed stone, blue metal, or river gravel. These options are far better than standard gravel and will help create high-quality concrete that can be used for just about anything.
Last but not least, we have water. It is a general rule that the water should be clean, fresh, and drinkable. If the water contains minerals, it will cause the concrete mix to be of lower quality.
How is the concrete ratio calculated?
The concrete ratio is usually calculated differently depending on where and what we will use the concrete for.
The so-called classic ratio for cement mix is called the 1-2-3 concrete-mix. This means that the ratio is supposed to be made from 1 part cement powder, 2 parts sand, and 3 parts washed aggregate. We can also add water to the mix to get the desired consistency.
What is Cement be used for
Cement can be used either as a binder for various different construction projects. It can also be used for various different household applications, such as staircases, an adhesive to tiles, pool decking or a concrete driveway.
Should you mix concrete yourself or leave it to a professional
Because preparing the concrete mix is so important, it is advised that you have a professional do it for you instead of you doing it yourself. The concrete mix ratios can vary depending on their purpose, so there are certain things to be taken into consideration when preparing the mix.
For example, professionals know that the water to cement ratio can directly impact the strength of concrete at a given age. The lower this ratio goes, the higher the strength of the concrete will be.
Also, there is a difference between the various mortar types that should be taken into consideration. Mortar mix ratios also vary depending on their use.