Mortar and concrete: the main components and methods of

Concrete and mortar for its preparation are among the most important, and therefore highly sought-after components at any construction site. When large-scale work, these materials are used in the literal sense of "on an industrial scale", because any master must thoroughly examine all the nuances of making such compositions. This is the issue we will devote to this article.

We define the terms

To avoid confusion, the very beginning determine what the difference between the mortar and concrete.

• The solution is a mixture of water and a binder - a material that, when dried, will polymerize and form a monolithic structure.. Cement, clay or gypsum is most often used as a binder in building mixtures.
• In addition to water and binding components, fillers are usually added to the composition.. The filler can be sand, gravel, polymer granules, expanded clay, steel or plastic fibers, etc. Fillers largely determine the properties of the material, which will turn out when frozen.

• If we talk about concrete, it is a building stone of artificial origin. Concretes are most often obtained after hardening of the cement slurry with a gravel, rubble or pebble aggregate for concrete.
• Concrete of various kinds is used in construction, ranging from heavy-duty, made of high-quality cement and granite, to light, which use claydite or pumice as a filling.. A separate category of materials are cellular concrete with a large number of air-filled pores.

Note! In spite of the fact that a rather strong material is obtained from such components, its additional reinforcement may be needed. To this end, steel reinforcement is introduced into the structure, which increases the resistance of concrete to bending loads.

Briefly summarizing all the above, the difference between the mortar and concrete is as follows:

• Not every mortar becomes a concrete after polymerization.
• Virtually any concrete is based on mortar, but other components are required to provide the basic characteristics of the material.

At first glance it seems pretty simple. But if you try to apply this knowledge in practice, immediately there are some nuances. We will dedicate the following sections to them.

Main components

Binder

As we noted above, the composition of the concrete solution necessarily includes a binding component, aggregate and water. We will analyze these elements to give you the necessary information for independent work.

So the first component is the binder. It is responsible for the hardening of the material during the evaporation of the liquid.

As such an ingredient in construction solutions are used:

• Cement - the most common option. Regardless of the type of cement (and here Portland cement, slag Portland cement, pozzolanic, alite compositions, etc. are isolated) the material first reacts with water, passing through the hydration stage. At this time, the cement is gaining strength, because the process of drying concretes on such a binder trying to slow down.

• The strength of the material, which is obtained by the polymerization of cement binder, is determined by such an indicator as the brand. To date, in the mass construction are actively used cement brand M100 - M600.
• Gypsum can also be used in mortars. Gypsum mixtures are often used in finishing for leveling surfaces; however, with the addition of certain components, structures with sufficient bearing capacity can be made of them.

Note! Gypsum compounds are prone to adsorption of water, because they require additional waterproofing treatment.

• Clay - a material that has been used in construction since ancient times. Nowadays, clay-based solutions (naturally, with modern modifying additives) are mainly used in the laying of stoves, fireplaces, etc. In addition, the addition of alumina to the cement allows to obtain concrete with high fire resistance.

• Polymeric materials can also be used as binders. A mixture of polyurethane base with mineral filler allows to obtain polymer concrete, which is used for arranging floor coverings with high wear resistance.

Filler

Now let's talk about the component that, in fact, determines whether concrete or mortar will work.

All fillers can be divided into two functional groups: some increase the strength of the building stone, others - improve its thermal insulation characteristics.

• The first group includes crushed limestone, gravel, granite, pebbles, etc. Crushed stone is introduced into the building mixture for its hardening: binding to the cement, it forms a monolithic structure. Moreover, the stronger the mineral from which the aggregate was obtained, the higher the mechanical properties of concrete.

Note! In some cases, iron fragments can be used (in the production of heavy-duty concretes), as well as large stone (in this case, we will receive butobcrete).

• The second group of aggregates consists mainly of porous materials - pumice, vermiculite, perlite, expanded clay, etc. Due to the special internal structure, they increase the volume of air in the thickness of the material, reducing its thermal conductivity.

• Separately, it should be said about the sand. This material binds to the cement and provides the mortar with the characteristics needed to connect with the filler and reinforcement. When introducing sand into the mortar, it is important to observe the proportions of the mortar for concrete: add too much, and the cement binding force will not be enough to form a solid monolith.

In addition to these components, the mechanical properties of the building stone can be improved by reinforcement. To do this, use either metal rods, pipes and wires of different diameters, connected in bulk frameworks, or fiber for concrete - fibers of high strength, evenly distributed in the material.

Cooking method

Proportions of popular compositions

Making a concrete solution with your own hands, it is important to choose a ratio of components that will meet the requirements put forward to the finished composition. This applies to both strength and other characteristics, such as thermal conductivity, water absorption, frost resistance, etc.

Examples of recipes for commonly used mortar are given below:

Note! Examples of the exact dosage for obtaining solutions of a certain brand are given in the images in this article.

In drawing up the proportion, it must be borne in mind that the SNiP on concrete and mortars (the main document is a set of rules SP 82-101-98, governing the preparation of mortars) contains instructions on the ratio of components for most situations. It is worth studying this standard to facilitate the selection of components to create a structure with the required strength.

Kneading and use

As for the practical application of the knowledge gained, the instruction for the manufacture and pouring of building mixtures is no different in complexity.

Below we describe the technology by which the most demanded concrete is prepared:

• In a sufficiently large capacity or concrete mixer we fall asleep dry cement and sifted sand.

Note! Sifting sand is needed to remove organic pollutants that degrade the characteristics of the material.

• Thoroughly mix the composition, ensuring its uniformity.
• Add gravel and repeat mixing. As a rule, when using a concrete mixer it takes no more than 5-7 minutes.
• Then we perform mixing the composition with water. Water should be added gradually, making sure that the solution was not too liquid.
• At the final stage of mixing, modifiers can be introduced into the composition - hardeners, means for increasing plasticity, anti-frost additives, etc. In relation to the cost of the main components, the price of modifiers is low, but they can improve the quality of concrete very significantly.

Note! Unlike gravel, porous fillers are injected into liquid cement, otherwise it will be difficult for us to distribute them throughout the material.

After that, our future concrete can be considered ready for use.

And here we can do in several ways:

• Pour the material directly into the formwork and leave there until the final hardening.
• Using hand tools, fill in cracks and grooves on an existing structure.
• Lay the solution in the form to obtain building blocks.

In any case, it is important for us to provide concrete with an optimum mode of drying for the entire period of strength set-up, which in natural conditions is about four weeks.

Conclusion

Understanding the difference between concrete and mortar, as described above, as well as knowing the proportions of the most frequently used building materials is worth every master. Naturally, knowledge comes with experience, but a beginner can get ready for work by studying the recommendations in the text and watching the video in this article.