TEST OF RECOVERY OF pH IN CARBONATED CONCRETE IN A STRUCTURE OF 50 YEARS OF LIFE.

ALKALINITY RECOVERY TEST

ALKALINITY RECOVERY TEST

ALKALINITY RECOVERY One of the most serious and common pathologies in concrete is carbonation. With the passage of time external agents, and in particular the ambient humidity, penetrate through the capillary network of structures, accessing the inside of the concrete, by capillary action: coating concrete loses alkalinity that keeps the reinforcement protected.

Therefore, this loss of alkalinity (pH of concrete down) below a critical value located around 9.5 cannot guarantee the reinforcement protection, and then, start the pathologies: corrosion of reinforcement, reinforcement section loss, which decreases the resistance of the concrete and durability, so the remaining useful life of the structure is significantly shortened

PASSING OF TIME, EXTERNAL AGENTS (AMBIENTAL HUMIDITY...)

CARBONATION

↓ ALKALINITY

PATHOLOGIES: ↓ DURABILITY

• SECTION LOSS •↓ RESISTANCE • ETC

REINFORCEMENT CORROSION

Structure of concrete with pathologies Carbonation is a process linked to the concentrations of CO2 present in the air, the presence of humidity and ambient temperature. If there is a direct access to the inside of the concrete, would not occur the carbonation process, which would avoid the oxidation, appearance of pathologies, etc. The ideal thing would be to completely seal the porous concrete network access: This what we get with the CATALYZED NANO‐CRISTALLIZATION.

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ALKALINITY RECOVERY TEST

NANOCRISTALLIZATION PROCESS The products that we use are nanosilicates. They penetrate through the pores and react with the calcium‐free concrete and water into quartz, crystal sand, which filled all of the capillary network. It creates a crystallized barrier that will prevent the entry of water, air,...

Our products are completely innocuous, mineral, and are based on the crystallization of silicate of sodium (our product base) and free calcium Ca+ existing in most building materials, to become small crystals internally that will prevent the passage of fluids through the interior of the same.

The performance of our products is based on several very basic concepts: 



They are nanofiltered until a product whose components have a molecular size  This allows them to penetrate any micro‐pore or capillar of any material, by polishing or vibrated it is.

Your insight is based on capillarity and surface tension  It applies with low pressure spray and a powerful mineral catalyst makes contact with the material into a gel that will penetrate by capillary suction of the material up to 20 cm during the first 3‐4 days to crystallize completely in 15 days more.

This will generate a network internal nanocrystalline should bring to concrete durability, increased resistance and protection against any type of environment.

Internal representation of the nanocristallization CONTROLL®INNERSEAL, sodium nanosilicates

Also is achieved recover the alkalinity of the concrete, as shows the essay that is describes below.

TEST OF RECOVERY OF pH IN CARBONATED CONCRETE IN A STRUCTURE OF 50 YEARS OF LIFE. The laboratory of engineering and environment IMASA, has produced a report of the results of the test carried out on two samples: a cylinder of reinforced concrete from a structure of 50 years old with carbonation.

The untreated sample essay gives a pH 8.8, so, below the critical pH

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ALKALINITY RECOVERY TEST

After application of the nanocristalizacion with silicates of sodium, and within 21 days, with an essay by dilutions have seen increasing the alkalinity of the concrete (pH 10.1) and therefore the recovery of inhibiting's function own concrete on the reinforcement, to overcome the critical barrier of 9.5.

(TEST OF COMPLETE REPORT IN ANNEX 1)

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ALKALINITY RECOVERY TEST

CONTROLL®INNERSEAL: Due to the high power of penetration of our solution (approx. 20 cm), the product has sealed, permanently the pores and fissures up to 2 mm from the concrete, preventing any filtration. All the pores of the concrete are filled in CONTROLL® INNERSEAL, silicates of sodium, which reacts with the water and the concrete‐free calcios, and become a gel of silicates of calcium, in 15 days, have solidified and have become a few glasses insoluble and unchangeable.

PASSING OF TIME, EXTERNAL AGENTS (AMBIENT HUMIDITY...)

APPLICATION OF

CONTROLL® INNERSEAL

↑ DURABILITY "RENEWED" CONCRETE

STOPS THE CARBONATION PROCESS

ALKALINITY RECOVERY

↑ RESISTENCE

With this test we can demonstrate the properties of the nanocristallization in our sector. With test and the results obtained are summarized in the following graphic:

ANNEX 1. REPORT OF TEST RESULTS:

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