Protection of concrete from moisture: methods and materials

How to protect concrete from moisture? In this article, we have to analyze several popular solutions that are applicable both for waterproofing foundations and basements, and for protecting capital walls from precipitation and seasonal fluctuations in humidity.

Classification

All waterproofing materials are divided into three main categories.

Useful: roll and coating materials are usually applied on the other side of the foundation or enclosing structure with which excessive static pressure of water is present. Otherwise, there always remains the risk of detachment of the protective layer, violation of its integrity. Penetrating waterproofing is devoid of this restriction.

Obviously, we are most interested in the last category of waterproofing. It is with her that we will get to know each other closer.

Possible solutions

Iron

The simplest and cheapest possible treatment of concrete from moisture is reduced to the iron-plating of the surface (the application of cement milk). Cement penetrates pores and microcracks, completely or partially clogging them. Of course, for the foundation of such waterproofing is not enough; but ironing the cement plaster of the facade will noticeably reduce water absorption.

Liquid glass

If sodium liquid glass is added to the cement-sand solution (an aqueous solution of Na2O (SiO2)) in a ratio of approximately 1:10, moisture-proof concrete with a very short (no more than half an hour) setting time is obtained. This recipe is often used to seal seams of sewer and water wells, block foundations and cracks in the floors of basements.

Processing with liquid glass is quite capable of reliably waterproofing the surface of the finished concrete product. Doing this work with your own hands is more than easy: the material diluted with water in a 1: 1 ratio is applied to the concrete with a brush, roller or spray.

Tip: undiluted liquid glass, applied in one layer, penetrates the concrete by an average of 2 millimeters. If the treatment is carried out with an aqueous solution and in several stages, the depth of impregnation will increase to 15-20 mm.

Water repellents

How to treat aerated concrete from moisture, if it is used to build the external walls of a residential building?

In this case, hydrophobic silicone-based primers will come to the rescue. Instructions for their use is also very simple: ready-to-use or diluted with water at a concentration specified by the manufacturer is applied to the surface of the facade in two or three layers without prior drying.

Protecting aerated concrete from moisture using a water-repellent solution solves several problems at once.

Specify: silicone-based water repellents are not just for aerated concrete. They can process all porous materials: heavy concrete, limestone, plaster, etc.

The composition is applied on a dry basis. A moisture meter for concrete, an uncomplicated electrical device that measures the resistivity of a surface area, will help assess the moisture level of a structure.

The average price of water-repellent products made in Russia is 150 rubles per kilogram. The only drawback of the solution is the limited adhesive qualities of the facade after processing: it can be painted only after six months.

Crystallizing Formulations

Пенетрон, Кристаллизол и их многочисленные аналоги отличаются от перечисленных выше решений принципом действия: упрощенно говоря, они не транспортируют материал для заполнения пор по капиллярам с поверхности, а создают его на месте (см.также статью «Пигменты для бетона: основные характеристики, сфера применения и методы самостоятельного приготовления»).

Chemical additives cause the accelerated crystallization of calcium salts (the main component of Portland cement) upon contact with water. The crystals securely fill the pores of the concrete.

What is the result?

• The most obvious result is the impossibility of moisture penetration into the concrete during the external processing of the structure.. If the walls of the basement are treated with the same Penetron from the inside, the groundwater will no longer find a way into the interior: the impregnation penetrates the concrete 40-60 centimeters.
• About vysola and mold, of course, you can also forget. For their appearance requires moisture.
• The frost resistance of concrete increases on average by 100 cycles.. On the practical side, this means an increase in the lifetime of the capital walls by 150–200 years.
• Finally, impregnation of concrete from moisture increases its compressive strength: the absence of pores prevents the material from crumble under load..

It is curious that Penetron and its analogues provide in some way self-healing waterproofing. Where water begins to penetrate concrete through new cracks and pores, the growth of calcium salt crystals immediately resumes. What is especially pleased - waterproofing measures can be carried out with damp walls or foundations.

Where do new cracks in concrete structures come from? The main reasons are shifts and frost swelling of soils, as well as installation work. During the perforation of technological holes and openings, shock vibration is destructive for concrete.

What to do?

1. In the first case, the problem is solved by reinforced reinforcement of structures. The foundation connected by reinforcement into a single rigid frame will not be deformed during any ground movement.
2. In the second, using less destructive work methods. So, cutting reinforced concrete with diamond circles, and fittings with a gas cutter or a conventional abrasive wheel, is far less destructive than using a jackhammer. Diamond drilling holes in the concrete is much more preferable than the work of a hammer drill.

Conclusion

In the framework of the short review we have listed only a small part of the possible solutions. As usual, the video in this article will offer the reader additional information (find out here how the concrete is heated by the welding machine).

Successes!