Concrete is one of the most used materials in the construction area, both domestically and industrially. However, it is a composite product, so it is important to take into account the amount of each ingredient to achieve a mixture that is tailored to the needs of the project.
The history of construction would not be the same without concrete, also called concrete. This material has its origin in the first buildings with clay materials, since it was necessary to prepare a mixture with lime or clay to join the different pieces and thus raise walls.
However, although they are still used to make cement, the truth is that these binders were quite weak, so they easily succumbed to atmospheric conditions.
For this reason, in Ancient Egypt limestone rocks with gypsum and water were used to create the homogeneous pastes that made it possible to cover great architectural monuments, such as the Pyramid of Cheops, which is more than 4,000 years old.
Materials and proportions to prepare concrete
If you do not know how concrete is made, it is important that you first know the materials that are needed. It is necessary to clarify at this point that the density of concrete varies according to the proportions of the ingredients used, therefore, it is essential to define the use before preparing the mixture .
Generally, concrete should be one part cement, two part sand and three part gravel, which is known as 1 m3 1: 2: 3 ratio concrete. As for the amount of water, it depends on the work to be done, but a proportion equal to that of cement may be sufficient.
For one-off DIY jobs, such as plugging a hole in the wall, a firm mix that carries little water is used, but for formwork in large constructions, more water needs to be added to facilitate the settling of the material in corrugated steel structures and at the same time reduce the weight of the reinforced concrete.
However, it must be taken into account that while the plasticity of the concrete increases, the water also decreases the final resistance of the concrete, therefore, it is not advisable to add a lot of water to the mix, unless it is a structure with a good metal reinforcement.
On the other hand, the components of the concrete can define the quality of the construction. In most cases, Portland cement is used as the main binder, a product composed of portions of lime and clay heated at high temperatures, which is very strong, durable and economical, making it suitable for large projects.
However, currently there are additives specially designed to change the properties of concrete, such as setting time , consistency, among others, thus speeding up processes. The quantity of these products depends on the proportions of the concrete.
Steps to prepare concrete at home
The dosage of homemade concrete is the same as for engineering works, but the preparation varies, mainly because of the proportions. In large constructions, an industrial concrete mixer is used , because it is necessary to mix considerable amounts of material.
For its part, in homes the concrete is generally mixed manually, using a spatula and a bucket for minor jobs, but if it is a larger quantity, it is more practical to do it on a wide and flat surface. Let’s see below the step by step to make concrete at home directly on the ground.
Define the proportions
The first step is to define the amount of each material that we are going to use to make the concrete. For this you can use a scale, but it is also possible to calculate the proportions if you have several cubes of the same size. If this is the case, you should fill a bucket of common Portland cement, two buckets of sand and three buckets of gravel, making sure that they all have the same volume of material.
It is good to clarify that the quantities do not have to be exact, but they do have to be as approximate as possible to obtain a good result.
Make a cone, heap, or volcano
If you are wondering how to make concrete for floors or any type of construction, you should know that an important part is the mixture of the aggregate ingredients and the binder when they are still dry. In this sense, it is best to do a pile on a smooth and flat floor.
The idea is to empty the buckets, but progressively, for example, add a little sand, some cement and concrete gravel, always on top of the pile so that the material spreads. In this way, you should add the interleaved materials to form a volcano-conical pile.
Mix aggregate materials
With the help of a construction shovel, you have to make a second pile next to the first, moving the materials from one place to another, always trying to drop the contents at the top of the volcano. You will notice that the materials begin to mix until they acquire a more neutral tone.
Experts recommend doing this procedure 3 times, so you should return the pile to the starting position and then redo the second volcano with the same material.
Add water and mix
This is the most important step when making concrete by hand, since if we add too much water the consistency will be very liquid, but if we add little it can be heavy and difficult to use.
For this reason, it is necessary to add the water progressively, because the necessary quantity depends on the aggregates; sometimes the sand is wet , therefore the mix will require less liquid.
You just have to make a hole in the center of the pile and proceed to place a little water. It is advisable to wait for the materials to absorb this first amount of liquid and then check if it is necessary to moisten a little more.
The idea is to move the dry ingredients from the edges of the volcano to the center, where you have added the water, and then stir with the tip of the shovel. It is important to mix everything well before adding more water.
Finally, it only remains to point out the importance of preparing the right amount of mixture according to the need, in order to use all the prepared concrete and thus not lose the materials.