Cement is a conglomerating material that is made up of a ground mixture of limestone and calcined clay, whose main property is its ability to harden on contact with water. Cement is widely used in civil works, but also for some home repairs, so it is always important to know how to make concrete and cement at home.
Cement has been one of the most used construction materials by mankind. The first cement was used in Ancient Greece and was a mixture of porous limestone of volcanic origin. Later, the Romans improved the original recipe, adding volcanic ash from Vesuvius, creating a material that has resisted for millennia under water, something impossible for modern cements that cannot withstand more than 60 years of immersion without deteriorating.
As a result of the wars and invasions that caused the fall of the Roman Empire, human beings forget what cement is made of and it is not until the 18th century that it is used again to create the foundations of lighthouses, in this case the recipe for cement already adds calcined lime.
However, it would not be until 1824 when modern cement would appear, patented as “Portland cement”, a white cement that comes from a mixture of limestone and clay calcined at high temperatures. In the 20th century, thanks to chemical and scientific advances, new varieties were created, such as liquid cement or fresh concrete.
In this sense, modern concrete and cement are a mixture of calcium silicates and aluminates, obtained by firing calcareous materials, such as clay, sand and volcanic stones. Each type of modern cement has a different composition, for example, white cement does not contain iron, but it does contain fluorite and cryolite, which is why it has a lighter color than other cements such as ferrous.
What is cement used for?
This building material is used for a wide variety of purposes as cement is very versatile and can be used to seal and protect walls, ceilings and floors. In this sense, the most common use of the material is to insulate homes and buildings, as well as to protect them from the penetration of water or to seal off an area from air circulation.
In this sense, it is important to know how to make cement for the ground, for example, to pave an area and turn it into a basketball court with which to play with Nike Revolution 4 sneakers. But it will also be necessary to know how to make very hard cement to build walls, as well as light cement, to seal those walls or their cracks.
What is needed to make cement?
First of all, to make cement you must have the right tools. In this sense, you need to have a sieve, a trowel and a container to mix, which can be a plastic bucket or, if you plan to make a large quantity, a wheelbarrow with which you can also transport the concrete without getting tired. If you need to make a very large mix, it is best to have a concrete mixer, since these machines allow you to mix huge amounts of cement and, as they keep the mix moving at all times, it will not dry out or harden, so you can work in large areas and with large amounts of cement.
As for the materials, to make concrete, cement, sand and water are required. Although it is possible to make cement without sand (light cement), it is best to have the correct cement-sand ratio, since this will be responsible for absorbing moisture. In this sense, for those who wonder how much cement and sand is needed per square meter, the correct measure is 3 measures of sand for each one of cement and water.
The sand used to make cement must be construction or river sand. This means that not all sand, such as beach sand, is suitable, with which the cement would not bind or would be of very low quality, obtaining a brittle and inconsistent result. In some cases, cement gravel is used, with which a much harder mixture is obtained.
It is also very important to maintain the correct water to cement ratio as too much water will make the cement too runny.
How to make cement step by step?
To make a homemade refractory mortar, that is, a consistent mixture of cement and sand, the first step is to sift the sand well. When sifting the sand, we seek to eliminate all possible impurities, removing small stones that will bother us when working with the mortar.
Once the sand is sifted, the indicated proportion is added to the cement, which is usually 3 measures of sand for each measure of cement. Next, the mixture of cement and sand must be stirred to render, and the same amount of water as cement is added. In this step, you have to be careful, because if the sand accumulates a lot of moisture, less water should be added, in this sense it is better to keep the amount of water short, since otherwise it will be a mixture that is too liquid and light.
To finish, mix everything well, with the help of a paddle until you achieve a homogeneous paste, without lumps and that moves well, being slightly stuck on the sides.
To work with the cement, it is very important to slightly moisten the areas where the paste has to be applied, since if the cement is applied directly on a dry surface, it will come off. Also, if we overdo it when applying the cement to any area, it is possible to remove the excess using a damp sponge or, in the case of dry cement, an esparto scourer.