Rusting reinforcement (rebar corrosion)

The work, step by step

General guidance based on the manufacturer data sheets. Site conditions differ: confirm the system with MCT before you start. Where we do not name a product, ask us and we will confirm the right one.

1. 1

   Step 1: Survey and test

   An engineer maps rust stains, cracks and hollow areas and checks cover, carbonation and chloride content. FerroGard-903 Plus is typically used up to about 1 % free chloride by weight of cement at bar level; above that, consumption is increased only after trials and corrosion-rate monitoring (FerroGard-903 Plus p.3).

2. 2

   Step 2: Repair cracked and spalled areas first

   Visible defects must be repaired by conventional methods: remove loose concrete, treat the steel and re-profile (FerroGard-903 Plus p.3). Clean bars by abrasive blast cleaning (MonoTop-610 p.3). Follow the spalling-concrete guide for the full sequence.

3. 3

   Step 3: Protect exposed steel

   Two coats of about 1 mm all round each cleaned bar, 2 mm minimum in total (MonoTop-610 p.2, p.3). For experienced professionals only (MonoTop-610 p.1).

   Sika MonoTop-610 Sika Professionals only

   Bonding primer as part of a concrete repair system Reinforcement corrosion protection as part of a concrete repair system (TDS p.1)

4. 4

   Step 4: Rebuild the cover

   Restore full cover with polymer-modified repair mortar. SikaRep PK is listed for increasing cover and replacing carbonated or contaminated concrete (SikaRep PK p.1). MonoTop-612 PK is sulphate resistant (MonoTop-612 PK p.1). SikaEmaco S 488 has high carbonation resistance (Emaco S 488 p.1).

   SikaRep PK Sika

   Repair of spalling and damaged concrete in buildings, bridges, infrastructure and superstructure works. (TDS p.1)

   Temperature stated in TDS

   +5 °C min / +35 °C max (TDS p.2)

   Pack

   25 kg Bag

   Sika MonoTop-612 PK Sika

   Sika MonoTop®-612 PK is used for structural concrete repairs as well as general patching to concrete and mortars. (TDS p.1)

   SikaEmaco S 488 Sika

   SikaEmaco® S 488 is used for the structural repair of concrete elements such as: Columns, piers and cross beams of bridges, Cooling towers and chimneys and other industrial environments, Water treatment and sewerage facilities before subsequent coating, Tunnels, pipes, outfalls and all below grou… (TDS p.1)

   Pack

   25 kg bag

5. 5

   Step 5: Treat sound concrete with a corrosion inhibitor

   Where concrete is undamaged but the steel is corroding or at risk, apply FerroGard-903 Plus to saturation by brush, roller or spray on a surface free of render, coatings and laitance. When the last coat turns matt, wash with low-pressure water (FerroGard-903 Plus p.1, p.4). It penetrates about 25–40 mm in 1–2 months (p.2).

   Sika FerroGard-903 Plus Sika

   For the corrosion protection of steel reinforced concrete structures above and below the ground. (TDS p.1)

   Temperature stated in TDS

   +5 °C min. / +40 °C max (TDS p.2)

   Pack

   25 kg pail

6. 6

   Step 6: Keep water and chlorides out

   Seal with Sikagard-705 L silane, 2–3 coats; it reduces corrosion even in cracked concrete and stops further chloride migrating to the bars (Sikagard-705 L p.1, p.2). Or use an anti-carbonation coating: Sikagard-680 S Betoncolor or Sikagard-550 W Elastic (G) (p.1).

   Sikagard-705 L Sika

   Sikagard®-705 L is used as water-repellent impregnation (hydrophobic treatment) for absorbent substrates such as concrete in civil engineering or building concrete structures subjected to heavy stress due to freeze and thaw cycles and de-icing salts and chl… (TDS p.1)

   Temperature stated in TDS

   +5 °C min. / +35 °C max (TDS p.2)

   Pack

   18 kg pail and 180 kg drum

   Sikagard-680 S Betoncolor Sika

   As a protective and decorative coating for: The protection and enhancement of concrete cementitious substrates on building and infrastructure elements, Reducing the deterioration of concrete and assisting with controlling the corrosion of any embedded steel reinforcement, Increasing the service l… (TDS p.1)

   Temperature stated in TDS

   +5 °C min. / +35 °C max (TDS p.3)

   Sikagard-550 W Elastic (G) Sika Request a quotation

   Sikagard®-550 W Elastic (G) is used for protection and enhancement of concrete structures (normal and lightweight concrete), especially exposed outdoor concrete surfaces with a risk of cracking. (TDS p.1)

   Temperature stated in TDS

   +8°C min. / +40°C max (TDS p.3)

7. 7

   Step 7: Build new work to resist corrosion

   For new pours, jackets or extensions exposed to chlorides or industrial chemicals, add Sika FerroGard CI 222, a corrosion-inhibiting admixture, to the concrete (FerroGard CI 222 p.1).

   Sika FerroGard CI 222 Sika Request a quotation

   Sika® FerroGard® CI 222 typical uses: Concrete bridges, highways and pavements exposed to de-icing salts, Concrete marine structures operating in chloride environments, Concrete tunnels, infrastructure or retaining walls, Concrete in industrial plants where corrosive substances are present, Concr… (TDS p.1)

   Pack

   05 ltr jerry can 20 ltr plastic can 200 ltr drum 1000 ltr IBC Bulk supply in tanker is…

Steps and product facts are taken from the manufacturer data sheets (page cited). Products are named only where the data sheet confirms the use; quantities follow a site visit or photos. General guidance: check the data sheet or ask us before you start.