The task was to prepare a solution for waterproofing a concrete coating. In the composition of the solution, the dominant role will be played by the drug with the trade name “Liquid Glass”. First, a little theory.
What is “Liquid glass”? Essentially it is silicon dioxide in its pure form. As you know, concrete contains calcium compounds: calcium carbonate, calcium oxide, calcium hydroxide. And silicon dioxide, which is present in Liquid Glass as a base, binds free calcites, turning into a gel. Is it good? Undoubtedly. There is only one BUT. Liquid glass is quite thick. And if used in its pure form, it simply forms a film on the surface of the concrete. But it doesn’t penetrate inside. Our task is to saturate the concrete with the preparation to the maximum possible depth. This is exactly why we will be “fidgeting” with the composition.
How to make water-repellent impregnation for concrete
So, for our solution we will take 5 liters of water. For this volume of water you will need half a liter of “Liquid glass”. Those. the proportion is 1/10. The result is a fairly liquid solution, which, when processed, will penetrate deeply into the concrete structure.
One more feature should be noted. The concrete surface should not be old. As you know, concrete “matures” for up to 27 days. It is within this period that impregnation should be completed. Treat “maturing” concrete. Capable of absorbing liquid. And the proportion of solution components 1/10 is ideal for this.
Having diluted Liquid Glass with water, we could have stopped there, but we have one more “magic” component. This is the Penta 811 water repellent. The chemical is potassium methyl siliconate. It is sold in the form of a concentrate, which should be diluted according to the attached table, depending on the grades of concrete being processed. For M400 concrete the proportion is 1/12. This means that for our 5.5 liters we need to add about 400 ml. To prepare solutions with Penta 811, you cannot use galvanized and aluminum utensils. And the finished solution retains its properties for no more than 8 hours. That's all the restrictions on use.
By mixing all the components and mixing them thoroughly, we get 6 liters of the finished product for treating concrete. Without delay, let's start processing. It is very convenient to apply the solution with a paint roller. The first layer of impregnation is absorbed quite quickly. After it dries, apply another layer. It is absorbed noticeably worse, but, despite this, we cover the concrete with our solution a second time. Leave until completely dry.
Examination. You can evaluate the effectiveness of a water-repellent coating by watering concrete with water from a bottle. It is clearly visible that the liquid does not wet the treated surface, but rolls off it. This effect will be even more noticeable on vertical concrete structures.
