What are dry building mixes?
Dry building mixes are very popular in the construction and repair industry. They are easy to prepare and apply. Dry mixes belong to the group of auxiliary building materials that are used for interior and exterior decoration of premises. Immediately after dilution with water, they become suitable for use and are used for plastering, laying tiles, brickwork, etc. accurate dosage of all components of the composition and compliance with the rules for mixing raw materials make it possible to obtain high-quality solutions for use in various construction areas.
Classification of dry mixes for construction
Modern mixes are used for different types of work, so they are usually divided into:
- masonry-thick-layer and thin-layer;
- glue-mounting, facing. They are used for laying tiles and stoneware tiles, aerated concrete blocks, bricks, etc.;
- – for leveling, making screed, creating a finishing layer. They can be either regular or self-leveling;
- repair-injection, volume-and surface-recovery;
- insulation-used for creating heat and sound insulation;
- plaster-light, special and heavy;
- putty-leveling and for creating a finishing layer;
- grout-for grouting joints up to 6 mm thick, and joints with a width of more than 6 mm;
- universal-mixtures that can be used during various construction and repair works.
Dry mixes are also classified according to the composition of the binder. They can be simple or complex. To create simple mixtures, use only one binding component, such as cement or gypsum. In complex mixtures, several astringent additives are used simultaneously. In addition, dry mixes are divided into special and universal, which can be used for most repair and construction work. So, for example, levelling mixes for putty are often used when pouring floors, starting finishing of wall panels, etc. dry mixes are used for both internal and external works. When working inside buildings, gypsum mixtures are most often used, thanks to which a favorable microclimate for humans is maintained in the room. When carrying out external works, mixtures based on cement are used – a substance characterized by high resistance to moisture, fire resistance and resistance to atmospheric phenomena. Dry mixes are classified according to the dispersion of the filler – they can be finely dispersed-the filler fraction does not exceed 0.315 mm, and highly dispersed – the fraction of 2.5 mm or higher.
Composition of dry mixes
The basis of mixtures can be gypsum, polymers and cement, and various additives are added to them, giving the composition the necessary quality characteristics. Substances used in the production of dry mixes are conventionally grouped into several groups:
- Mineral binders-lime, Portland cement, gypsum.
- Organic binder polymer powders based on ethylene, vinyl chloride, and acrylate.
- Fillers-chalk, quartz sand, amorphous silica, talc, asbestos, vermiculite.
- Water-retaining additives, plasticizers and substances that regulate the setting of the material.
Binders are added to mixes to improve their strength characteristics and adhesion. There is a distinction between hydraulic and non-hydraulic components. Hydraulic mixtures provide high resistance to water.
Modified additives for dry building mixes
Thanks to the use of modifying additives, dry mixes for construction acquire the necessary technical characteristics. In dry mixes, the proportion of modifying additives is about fifteen percent. Modifying additives can be of organic or inorganic origin. They increase the coupling of components with water, improve its coupling characteristics. Additives regulate spreading, are responsible for plasticity and durability during further operation.
Scope of use of dry mixes for construction
Dry mixes can be used for almost all types of work related to the construction and repair of premises. So, for example, a mixture of M150, created on the basis of sand and Portland cement, is used:
- for processing joints and seams;
- laying of bricks, stoneware, paving slabs;
- during plastering works;
- for leveling any surface;
- when concreting stairs;
- during the repair of floors and other reinforced concrete structures.
The M150 mixture is quickly applied to the surface and solidifies within 24 hours. Dry mix M200 can be used for laying bricks and blocks of aerated concrete, filling the foundation, when carrying out plastering works. It contains Portland cement, sand and modified additives. The mixture was created taking into account the requirements of GOST28013-98. material consumption is 10 kg per 1.9 liters of clean water. M300 is a self-levelling mixture, the main difference of which is a fast curing time. It is used not only for leveling floors, but also for pouring foundations, load-bearing structures, brickwork, and fastening reinforced concrete structures. The M300 mixture is characterized by maximum strength indicators, resistance to high humidity and temperature changes.
Advantages of dry building mixes
Due to the special composition and ease of preparation, building mixes are widely popular in the construction industry. The main advantages of dry mixes include the following factors::
- Easy to use and prepare – on the packaging of each mixture there is an instruction that allows you to get a high-quality and ready-to-use solution.
- Stability of the composition-all components are added to dry mixes in a strictly dosed form, so any composition retains all the specified characteristics.
- Cost-effective-the use of building mixes helps to save costs advantageously, since the mortar is applied in a thinner layer. In addition, the time spent on processing is significantly reduced, which is important.
- Uniformity and plasticity – if you follow the instructions, the solution turns out to be homogeneous and is well applied to any surface.
- High adhesive qualities-reliable adhesion to almost any substrate.
- Excellent sound and thermal insulation performance.
- Long shelf life even when stored for a long time, mixtures do not lose their original characteristics. They can be transported and stored even at low temperatures.
- Eco-friendly-all mixes intended for repairs and construction are absolutely safe for human life, so they can be used for both exterior and interior work.
When choosing mixtures for work, it is best to follow the rules for choosing materials from one manufacturer – they are perfectly combined with each other, guaranteeing quality and long service life.