Concrete M300, like any other, in principle,is almost universal material, which is currently used in many areas of construction and for various purposes. Each brand of this substance has its own properties, price, characteristics, production technology.
general information
M300 is a brand that is considered practicallyuniversal, as it has an acceptable cost and fairly good properties. In addition, the parameters of the concrete mix are determined in advance by GOST. Of course, in order to obtain high-quality concrete M300 as a result, it is necessary to use good raw materials. But here it is important to note that the composition of this substance includes as many as five different components.
Components for production
Естественно, что основным ингредиентом является cement. As a rule, the M400 and M500 brands are used, since they are characterized by the best properties. Using the same brand M200 is impractical because it may worsen the parameters of the finished concrete. Due to the fact that cement elements M200 are characterized by poor performance, in the future it will not be able to withstand the required loads.
By the way, when buying it is very important to pay attention to the shelf life. If it has expired, the quality of concrete M300, like any other, significantly reduced.
The second element is rubble.Most often granite, limestone or gravel is used here. It is worth noting that granules can vary greatly in size: it can vary from 5 to 70 mm. The choice of this filler is based on its strength. It should be twice the strength that would be required from concrete. In other words, the composition of concrete M300 with limestone will be 500-600, and with gravel - 800-1000.
If you follow this rule, in the futureget to avoid destruction of the structure. Here it should be added that if the gravel is contaminated, then it will have to be washed before adding to the composition.
Also concrete M300 contains sand.This brand of material implies the presence of sand granules ranging in size from 1 to 2.5 mm. In order not to degrade the performance of the future mortar, sand is also required to sift if it contains particles of dirt.
Ironically, water is essential.component affecting the quality of concrete. So, if you use a chemically or biologically contaminated liquid for mixing, then its properties will deteriorate. It is necessary to filter the water before use.
The last item that turns out to beA significant influence on the characteristics of concrete M300, is an additive. We are talking about various plasticizers and other ingredients that are added to the material, if necessary, to increase its frost resistance, for example, or other technical indicators.
Characteristics of the substance
As has already become clear, the quality of the M300 depends primarily on the components used. When using quality components characteristics of concrete will be approximately as follows:
- Water resistant - w8. This indicator says that we have a low permeability composition. The absorption of moisture to them does not exceed 4.2% of the volume.
- Frost resistance level - f200.
- Concrete of this brand belongs to the class b22, but b25 is also often written. Depending on the requirements for future construction, the class of mobility of the composition may vary from n2 to n4.
- The density of concrete M300 is 1800-2500 kg / m³. This parameter will vary depending on which filler is used.
- Stiffness - W2-W4.
- This concrete belongs to the class of heavy.
Application
Due to the fact that concrete M300 has quite good properties, which, moreover, can be adjusted by changing components, this composition has found wide application in construction work:
- It is used for the construction of facilities such as platforms, roads, curbs, as it can withstand high loads and does not crumble.
- With it, install walls or supports.
- Used in the construction of landings in apartment buildings, as well as for the stairs themselves.
- It is great for pouring monolithic foundations on which a multi-storey building can stand, and does not settle under pressure.
- It is used for the production of concrete products, as well as fencing.
It is also worth adding that this concrete is goodsuitable for the construction of sewage pipes, constantly exposed to high humidity, as well as being in a constantly changing temperature.
Components for self-made
You can buy a ready-made solution, but you can make it with your own hands. If you independently make the M300, then you need to know that it can be of two types:
- The first involves the use of cement brand M400. In this case, the ratio of components such as cement, sand, crushed stone, will be as follows - 1: 1.9: 3.7.
- The second type means that you have to use cement M500. Here the ratio of components will change and will look like this - 1: 2.2: 3.7.
Production
The weight of concrete M300, or rather one of its cube, canreach 2000 kg / m³. The recipe is quite simple, and for the successful production only the material itself and some devices will be needed. So, to get one cube of M300, you will need:
- 340 to 360 kg of cement;
- 800-850 kg of sand;
- 900-1100 kg of crushed stone;
- about 200 liters of water;
- about 10 kg of various additives (plasticizers and others).
To make such a quantity of materialNaturally, a concrete mixer will also be needed. In addition to it, a shovel is needed to load dry components, buckets for pouring water, as well as measuring containers so that it is possible to observe the proportions of concrete M300.
Manufacturing technology is quite simple:
- The first thing to do is pour 3/4 of the total water in the mixer.
- After that, the equipment is turned on and you can begin to fill the cement.
It is necessary to mix water and cement, until a homogeneous mass is formed, only then you can add crushed stone first, and then sand.
Specific gravity and dry matter producers
To successfully carry out any work, inwhich need to use concrete, you need to know its specific weight, as this will help determine the required number of initial components. For example, if you take the figures given in the previous description and mix the solution with them, you will get a cube with a specific weight of about 2400 kg. In this case, to create concrete M300, the flow will be about 30 bags of the mixture.
Of course, professional builders are notenjoy, but at homework it will help. It is also worth adding that the specific weight includes the weight of the reinforcement, if any, as well as the location of the solution.
To date, there are dry mixes thatmore often called simply sand concrete. It is important to note here that the recipe for preparing concrete M300 gave impetus to the development of such a substance. It is packaged in bags weighing from 25 to 50 kg. True, the cost per bag will exceed the cost of the same amount of M300 by about 150 rubles. However, sand concrete is used much easier and faster. In addition, the addition of rubble if necessary is also allowed.
Hardening features
Due to its characteristics, concrete M300 withsolidification is characterized by specific reactions. So, if the proportions were chosen correctly, then during this process crystalline hydrate appears. At this time, in fact, the interaction of cement and liquid occurs, which is accompanied by the formation of a new substance. This is very important to know, because if the liquid in this period of time is too small, the process itself will take longer, and the final strength of the concrete will decrease. In some cases, it may even shrink or crack.
If the ambient temperature is enoughhigh, then moistening should start no later than two hours after pouring. In the normal temperature range with sufficient air humidity, this parameter may increase up to 12 hours.
It is important to note that it is necessary to water the concreteOnly spray to avoid jet damage to a weak surface. Nodes and edges of the structure should be watered more carefully than just a flat surface.
