The waterproofing of buildings is always a very present issue, given the number of future problems that can be avoided. For some time now, an increasing number of companies choose to tackle the problem from the very choice of materials, instead of applying treatments a posteriori. This is how nanocrystallization has penetrated.
Although in Spain this technique is in an incipient state, the truth is that both in the US and in Europe itself (Germany, Norway, Sweden …) we could say that it is already more than consolidated. It is also applied to constructions as demanding as oil rigs, which are submerged at a depth of 350 meters with all that this implies for erosion.
Create a crystalline lattice
What exactly does it consist of? It is a chemical process that is applied to concrete, ceramics, mortars and natural stones, that is, to porous materials that are widely used in construction. In essence, it is about creating a stable network of nanometric crystals inside these materials, altering the behavior of their ions, atoms and molecules so that they bind to form this crystal network.
The process is especially applied to the silicates (sodium, potassium and lithium) that contain the mineral material, until they are converted into a kind of siliceous gel that when solidifies creates the crystalline lattice. And we speak in terms of “nano” because the size of the particle ranges from 01, to 0.7 nanometers (a nanometer is one billionth of a meter). These dimensions make the penetration of silicates much easier, which increases the density of the material on which we act.
Although it is true that this process takes between 15 and 20 days, the fruits of the work make it worth the wait. Most of the time, around 15 days, is dedicated to crystallization itself, since the first stage of the process, that is, the gelling phase, is around three or four days. The result of this process is a meshed network of nanocrystals that have the characteristics of pure quartz.
Among its main advantages, waterproofing stands out, which is the issue at hand. The reason is actually very simple: by increasing the density of the material – which is called “densification” – the permeability is significantly reduced, which prevents the absorption of water and humidity that, in the long term, would harm our constructions. However, waterproofing is not the only advantage of using concrete and mortar treated with this technique. Among other benefits we can also highlight:
- Greater corrosion protection. – Thanks to crystallization, it is possible to keep the pH of the materials above 11.4, which favors the inhibition of corrosion, avoiding oxidation.
- Energy efficiency. – The densification of the material, in addition to repelling water, also helps us to avoid the dissipation of temperature through the concrete.
- Flexibility and resistance. – Thanks to the characteristics of quartz, the resulting material has a lower expansion than untreated concrete, which favors a greater adaptation to the movements of the materials. In addition, the crystalline mesh guarantees greater mechanical resistance.
Due to all these advantages, nanocrystallization has become a great ally, not only for new construction projects, but also for renovations in which it is sought to tackle/solve problems of humidity, corrosion and it is required to have a good consolidation of the joints in repairs with concrete or mortar.In Spain, the technique is relatively new, but it has already been applied to a multitude of projects, some benchmark such as, without going any further in our own province, the waterproofing of the Alicante tram tunnels.