How to knead concrete: the composition and proportions of

20-01-2018

Building

Not a single building can do without concrete. This is a mobile and durable building material, which often acts as the foundation of a building. That is, the durability and practicality of the whole future house depends on its quality. So, you should understand the principles of its production in order to be able to take care of the reliability of your home.

Table of proportions how to knead concrete based on cement M400

How to do

So, this is the strongest building material we can do with our own hands. What does he have in his structure?

Composition

Cement is a fundamental ingredient that provides binding properties.

Tip: to create the foundation should not use cement grade lower than M400, because they are designed for use in places that do not have a significant load.

Water is a solvent medium that allows you to mix a combination of different ingredients.. At the same time, it does not split the components, but only brings them to the smallest particles and accompanies thorough mixing.
Sand - the small component fraction forming the first belt of strength. Usually it is preferable to use the river, but if you want to increase the moisture-insulating properties, it is well suited and career.

Photo sand and cement next to the connection

Rubble or gravel to create the main granite mass. If you hit the concrete with your hand, you will feel the pain of contact with these elements.

Cutting reinforced concrete with diamond circles is necessary precisely because of these hard elements.

Tip: if you want to warm the room, it is recommended to add expanded clay to the solution. It has a very low thermal conductivity and can perfectly improve the insulation.

Using claydite during concreting will help to create coziness.

Proportions

You can throw all of the above ingredients in a heap and mix by hand, but this will in no way guarantee the high quality of the resulting solution. Even more, most likely you will get stone-like porridge, which will not last long. Therefore, if you need a quality batch, try to observe the correct ratio of all components.

Proportions - how to knead concrete properly are repelled by the amount of cement used. That is, it is taken as one conditional unit, and the remaining additives are already carried out according to it. Thus, when it is indicated, for example, 1: 3: 5, this means that 10 kg of gravel and 50 kg of sand are needed per ten kilograms of cementitious mixture. Water is usually required half as much, in our case 5 liters.

Tip: all batches are recommended to be carried out in a concrete mixer. It will greatly facilitate your work and make the solution as homogeneous as possible.

The price of concrete mixers repeatedly pays for large volumes.

Instruction of batches of various grades of concrete looks like this:

M200 - 2.8 sand and 4.8 rubble are consumed per standard unit of cement. But such a foundation has a very weak strength due to the small amount of binder, therefore it is not usually used.
M300 - the ratio of all ingredients is 1: 1.9: 3.9. As you can see, the fractional components here are already smaller, which makes it possible for the solution to grasp much better. It is suitable for concreting floors in non-industrial premises.

You can also always buy an already mixed packaged solution.

M400 - here only 10 kg of fine sand and 27 kg of gravel are needed for 10 kg of the binder. This is a fairly durable and reliable composition that is suitable for the foundation of multi-storey buildings, walling and pouring floors in buildings with high loads.

M450 - the ratio of 1: 1.1: 2.5 components is necessary in cases when unique improved strength properties are required. With such a composition, you can allow in the future any load on the final structure.

All of the above combinations are also applied special modifying additives.

They, of course, increase the final cost of the finished composition, but also endow it with additional technical characteristics:

Plasticizers. Concrete is made more plastic, which allows its use on moving parts and protects against premature cracking.

An example of a plasticizer that increases the elasticity of the finished structure

Accelerators. Significantly reduce the setting time of the binder. It is especially convenient to use them when it is necessary to hand over the object soon.
Antifreeze additives. Prevent the crystallization of water in the composition of the concrete solution. Thanks to this, construction work can be carried out even in winter.

The possibility of concreting at sub-zero temperatures

Anticorrosion fluid. Protect against rust on the fittings used in the construction of the foundation. If there is a lot of metal involved, then protection against the destructive effect of moisture is simply necessary, since you cannot prevent it from hardening in concrete.
Strength boosters. If the binding properties of cement grades M400 and M500 are insufficient in your case, then additional components will help you to strengthen the strength of concrete.

In addition, many types of modifiers have a combination of different properties. So carefully study the annotations accompanying them to achieve the most optimal result for your case. (See also the article Fiber for Concrete: Features.)

Conclusion

Concrete is used in construction everywhere and the strength and durability of the entire building directly depends on its quality. Therefore, its batch should be approached with due attention and responsibility. Above are all the components involved in the creation of this solution, and their proportions for different brands. Do not forget also about the modifiers, allowing to achieve additional quality indicators.

Kneading of concrete - a responsible matter

The video in this article will provide you with an additional amount of information regarding the materials presented.

Follow all recommendations, and your concrete solution will be a reliable support for any design.