Do you need a concrete path or do you want to build a spacious garage and are you sure you can handle the construction yourself? It is neither difficult nor very easy, but it is a feasible project if you know how to get a mixture of cement, aggregates and additives correctly.
Apparently, concrete can be quite easy to obtain. If you have quality materials and a recipe tailored to the project. Go through this article and find out what steps you need to follow for everything to go well and get a compact and durable concrete.
Because the dust used can affect your eyesight and skin, the components of the protective equipment enter the first positions in the list of necessary materials. You need glasses to prevent powder from entering the eyes, a mask for respiratory protection, which is good to buy from a specialty store, although medicinal ones are also good, and thicker rubber gloves to limit contact. with the skin.
For the actual mixture you need a mix of cement, gravel, sand and additives, a water bucket or hose connected to the pump or faucet, a blender for mixing, a shovel for casting, a plastic wheelbarrow to make the mixture and a brush. You can also make the composition in a bale or in a larger bucket or in a can, but it is easier to work in a wheelbarrow, especially if you have to transport the material after homogenization.
Ingredients to keep in mind
In short, concrete is a mix of cement, a powder composed of clay, limestone, gypsum, etc., and water, in which gravel and sand are added, plus various additives, depending on the project. When you mix them you get a homogeneous paste, which when dried becomes solid and hard.
It is useful to know what information the name of the type of cement you are buying gives you. Thus CEM means Portland cement and can be type I or II (CEM I or CEM II), AS means that it includes slag, 42.5 and 32.5 respectively indicates the strength class, measured in Newton per cubic millimeter, N tells you that the initial strength is the usual one, and R that it is a version with high initial resistance.
From the category of aggregates you can use sand with a grain diameter of 0 to 4mm, or from 4 to 8mm (pearl) and gravel with a diameter of 8 to 16mm (small stone), or 16 to 22.4mm (large stone).
The water is good to be taken either from the city network or from another source, recycled, but always clear and odorless. So avoid taking water from a cloudy and visibly dirty lake or pond.
What kind of concrete do you need
And the final composition, ie concrete, is in turn classified according to compressive strength, including two relevant digits in the name. The first suggests the resistance obtained using a sample with a cylindrical format, and the second one with a square profile.
Thus, a concrete of class C 6 / 7.5 is considered less qualitative and suitable rather for filling, filling and external correction (leveling, filling of gaps, support for harder concrete, etc.), than for the construction of structures that they need superior strength.
C 8/10 is a slightly more resistant concrete, easy to spread and level on large surfaces, recommended for reinforced or unreinforced screeds, lifting elements, screeds used for leveling.
With a C 12/15 concrete you can already pour foundations, belts or floor tiles between two floors. It is frequently used for single-level constructions and to raise pillars that do not require special structural strength.
If you want to build a house with a maximum of two levels, specialists will recommend as a starting point class C16 / 20, a medium level concrete as structural strength, suitable for foundation slabs, beams, belts, flooring, partition slabs and columns of structure.
Classes C 18/22, C20 / 25, C25 / 30, C28 / 35 are options with superior strength recommended for taller buildings and projects with increasing strength requirements.
Recipes to choose from
In order to make it easier for you to go straight to work, we offer you some clear recipes that you can put into practice immediately. These formulas are based on 42.5R type cement, and the quantities are designed to obtain at the end a cubic meter of concrete with which you can work.
If you want to build a concrete alley or level a floor, we will tell you that you can easily get a cubic meter of C 8/10 by mixing: 220kg cement, 587kg sand 0 – 4mm, 257kg sand 4 – 8mm, 413kg gravel 8 – 16mm , 545 kg large stone and 130 liters of water. Don’t forget that the formula takes into account a cubic meter of concrete as a result and adjusts the quantities accordingly, to get as much concrete as you need.
For those who prepare the foundation for a single-level house, garage or warehouse, the list of materials includes, for a cubic meter of concrete C 16/20: 280kg cement, 567kg sand 0 – 4mm, 252kg sand 4 – 8mm, 400kg stone small, 525kg large stone and 161 liters of water.
Preparation of the mixture
For each concrete wheelbarrow you have to calculate the mixture proportionally, determining how much you add from each ingredient. If you have a construction wheelbarrow with a 100 liter tank, you will always work with the 10th part of the recipe. For those who prefer to buy the already combined mixture from the store, this step is much simpler.
Add the dry ingredients for the first time, taking care to leave enough space for water in the deeper part of the wheelbarrow. Then pour the water with a bucket, measuring as accurately as possible the required amount. A softer concrete will pour more easily, but has a lower strength, while a too dry one is more difficult to apply correctly.
Then use the shovel to slowly and gradually pull the material dry in the water and homogenize it. Repeat this movement until you are sure that all the cement has gotten wet.
To know if the concrete has the right texture, carefully check the marks left when pulling the mixture with a shovel. Where the blade has entered the composition, the wall should be moist, almost smooth and shiny, and the material left on the sides should stand without slipping or leaking.