How to repair reinforced concrete

Descripción sistema

Reinforced concrete plays a very important role in our daily lives, as it is present in most building and civil engineering structures. However, despite its good behaviour in service, its durability is compromised by different pathologies that can affect it.

The most common and frequent is carbonation, a chemical process whereby the concrete loses its ability to protect the reinforcement against corrosion. Carbonation advances as a front in the concrete and when it reaches the reinforcement, in the presence of moisture, corrosion begins.

The rebars, as they rust, increase in volume, producing internal stresses in the concrete that result in spalling or spalling, which can eventually weaken the structure.

Reinforcement corrosion can also be caused by the action of chlorides, sulphates, etc.; this is known as pitting corrosion (it occurs at certain points of the reinforcement, in a discontinuous manner).

Related products

• PROPAM® REPAR TECHNO

Related products

• PROPAM® REPAR TECHNO
• PROPAM® REPAR TECHNO 40
• PROPAM® REPAR TECHNO 20
• PROPAM® REPAR 30
• BETOPRIM
• BETOPAINT
• BETOPAINT FLEX
• FLEXITEC
• PROPAM® REPAR 40
• PROPAM® REPAR 5
• BETOPOX® 93

Solution

The repair of concrete consists of four basic operations:

Substrate remediation. Mechanically remove the deteriorated concrete until the substrate has a pH of more than 9.5 and a percentage of chlorides lower than the minimum required.

Protection of the reinforcement.The reinforcement must be exposed on the entire surface where it is rusted.Clean the rust layer of the reinforcement with a brush or sandblast and then applyBETOPRIMas a protective primer against corrosion.

Corrosion inhibitor. Apply by spray, roller or brush CORTEC MCI 2021 if the service life of the reinforcement is to be increased against corrosion processes.

Protection of the final surface.The simplest way to protect the concrete against carbonation, chlorides and aggressive environmental chemicals is by means of a continuous coating based on BETOPAINT/ BETOPAINT FLEX anti-carbonation paint or FLEXITEC flexible cementitious membrane .

Recommendations

• The concrete substrate must always be firm (minimum tensile strength of 1 N/mm2), clean, free of cement slurry, oil, grease, traces of release agent, old paint, etc.
• The concrete repair can be carried out with thePROPAM® REPAR TECHNO range, in which case it is not necessary to apply the reinforcement passivating primer or the bonding bridge to the concrete, only water to dampen the substrate.
• In the PROPAM® REPAR TECHNO range, BETOPRIM passivating primer is only recommended if the steel is very close to the surface (<1cm).
• IfBETOPOX® 93is used as a bonding bridge,PROPAM® REPAR 30 or 40must be applied while the bonding bridge is fresh, i.e. within 4 hours after application.
• For thin cosmetic repairs, usePROPAM® REPAR 5. It is not necessary to applyBETOPOX® 93for this type of repair.
• Curing of repair mortars is essential for at least 24 hours after application to ensure that the product achieves the intended properties, wetting and protecting the surfaces already within the first few hours, especially if they are fast-setting.