Sika® FerroGard®-903
Penetrating, bipolar corrosion inhibiting, impregnation coating for hardened concrete
Sika® FerroGard®-903 is a surface applied bipolar corrosion inhibitor, designed for use as an impregnation of steel reinforced concrete. It is designed to penetrate the surface and then to diffuse in vapor or liquid form to the steel reinforcing bars embedded in the concrete. Protection with Sika® FerroGard®-903 both delays the start of corrosion and reduces the corrosion rate. Corrosion protection with Sika® FerroGard®-903 increases the service and maintenance life cycles by up to 15 years when used as part of a complete Sika® Concrete Repair and Protection System. How it works Sika® FerroGard®-903 is based on organic and inorganic inhibitors that protects both the anodic and cathodic parts of the corrosion cell. This dual action effect dramatically delays the initiation of corrosion and greatly reduces the overall corrosion activity. Sika® FerroGard®-903 penetrates the concrete and forms a protective monomolecular layer on the surface of the reinforcing steel. This barrier inhibits corrosion of the steel caused by the presence of chlorides as well as by carbonation of concrete.
- Suitable for method 11.3 (applying inhibitor to the concrete) for Principle 11 (anodic control), EN 1504-9
- Does not change the appearance of the concrete structure
- Does not alter the water vapour diffusion properties of concrete
Usage
- For the corrosion protection of steel reinforced concrete, prestressed, precast, post tensioned or marine concrete structures above and below the ground
- As a corrosion control treatment for undamaged reinforced concrete where reinforcing steel is corroding, or is at risk from corrosion due to the effects of carbonated or chloride contaminated concrete
- Steel-reinforced concrete, bridges and highways exposed to corrosive environments (deicing salts, weathering)
- Sika® FerroGard®-903 is especially suitable for extending the service life of aesthetically valuable fair-faced concrete surfaces such as historic structures
Packaging
20 kg container
Advantages
- Suitable for method 11.3 (applying inhibitor to the concrete) for Principle 11 (anodic control), EN 1504-9
- Does not change the appearance of the concrete structure
- Does not alter the water vapour diffusion properties of concrete
- Long term protection and durability
- Can be applied to the surface of existing repairs and to surrounding areas to prevent the development of incipient anodes
- Protects both, cathodic (principle 9) and anodic (principle 11) zones of reinforcing steel
- Can be applied where other repair/prevention options are not viable
- Easily applied by either spray or roller to all existing reinforced concrete.
- Economic extension of the service life of reinforced concrete structures
- Penetration depth can be tested on site using the Sika “Qualitative Analysis Test”
Colour
Colourless to Pale yellow liquid
Product Details
APPROVALS / STANDARDS
- BRE, The use of surface applied Sika® FerroGard®-903 corrosion inhibitor to delay the onset of chloride induced corrosion in hardened concrete, BRE Client Report No. 224-346, 2005
- Mott MacDonald, Evaluation of Sika® FerroGard® 901 and 903 Corrosion Inhibitors, Ref. 26’063/001 Rev A, April 1996.
- SAMARIS (Sustainable and Advanced Materials for Road Infrastructure) – Final Report, Deliverables D17a, D17b, D21 & D25a, Copenhagen, 2006
- Mulheron, M., Nwaubani, S.O. , Corrosion Inhibitors for High Performance Reinforced Concrete Structures, University of Surrey, 1999
- C-Probe Systems Ltd., Performance of Corrosion Inhibitors in Practice, 2000
- Wolfseher & Partner, Materials Technological Investigation, Report No. 96.144.11 and Report No. 98.115.11.
Chemical Base
Amino alcohol and inorganic combination
Shelf Life
12 months from date of production
Storage Conditions
Store properly in undamaged and unopened, original sealed packaging. Store in a cool environment.
Density
~ 1.14 kg/L (at +20 °C)
Viscosity
~ 25 Cps
pH-Value
> 8
System structure
Sika® FerroGard®-903 is part of the Sika® Concrete Repair & Protection Systems:
| Repair system | Sika MonoTop® or SikaTop® mortars |
| Reinforcement corrosion control | Sika® FerroGard®-903 |
| Concrete protection | Sikagard® Coatings and or Sikagard®
|
Penetration depth
Site surveys and experimental tests have shown that Sika® FerroGard®-903 can penetrate through concrete at a rate of a few millimetres per day and to a depth of approximately 25 to 40 mm in 1 to 2 months. This penetration rate can be faster or slower dependent on the porosity of the concrete. Sika® FerroGard®-903 penetrates through both liquid and vapour phase diffusion mechanisms.
Note: If after application of Sika® FerroGard®-903, the concrete surface is coated with protective coatings (cement based, acrylic or impregnation) or hydrophobic impregnation, the rate of diffusion of the inhibitor is reduced but not stopped as the mechanism of diffusion liaises then only on the vapour phase.
As concrete quality and permeability differ, it is recommended to perform some preliminary depth profile testing by the Sika “Qualitative Analysis” to assess the specific penetration rate.
Application
Ambient air temperature
+5 °C min. / +40 °C max.
Substrate temperature
+5 °C min. / +40 °C max.
Consumption
Generally ~ 0.500 kg/m2
For very dense concrete with low permeability, the rate of application of Sika® FerroGard®-903 can be reduced but must not be lower than 0.300 kg/m2.
To assess project requirements, consumption and depth of penetration shall be checked on site using the Sika “Qualitative Analysis” – refer to the relevant method statement.
APPLICATION
Sika® FerroGard®-903 is supplied ready for use and must not be diluted. Do not shake the material prior to use. Following transportation, some foam may appear in the pail – this does not affect the performance of the product.
Sika® FerroGard®-903 shall be applied to saturation by brush, roller, low pressure or airless spray equipment.
After the application of the last coat, as soon as the surface become mat, do a low pressure water cleaning (water hose).
The day after application, the treated surfaces shall be cleaned by pressure washing (~ 10 MPa – 100 bars) to remove any traces of soluble salts that may have deposit at the surface.
To improve penetration speed, concrete treated with Sika® FerroGard®-903 may be dampened once or twice for 1 – 3 days after application.
Number of coats:
This is dependent on the porosity and moisture content of the substrate and the weather conditions, normally 3 to 5 coats are necessary to achieve the required consumption.
Waiting time between coats:
This is dependent on the porosity of the concrete and the weather conditions, normally 30 minutes to a few hours to allow the surface to dry between coats. Allow the surface to dry out between coats to a matt damp appearance.
Overcoating with coatings:
Two days (or later) after the application of Sika® FerroGard®-903, the treated surfaces must be washed down once or twice with water and allowed to dry for at least 3 days.
Then clean the surface thoroughly by water jet (100 – 150 bars) and allow drying for a further 3 days.
If the application is carried out as described above, no further treatment is required before overcoating with Sikagard® hydrophobic impregnations, Sikagard® breathable coatings or Sikafloor® products (Refer to appropriate Product Data Sheet for application details).
If non Sika coatings are to be applied, please contact the manufacturers technical department for confirmation of compatibility with Sika® FerroGard®-903 or undertake compatibility and adhesion site trials.
Overcoating with cementitious products:
Allow areas treated with Sika® FerroGard®-903 to dry for a couple of days.
Rinse treated surface with high-pressure water jet (~ 100 – 150 bars). As a bonding agent for cementitious repair systems, only SikaTop® Armatec-110 Epocem® is to be used (follow the information in the product data sheet).
When Sika® FerroGard®-903 is used within a patch repair or before a cementitious overlay, Sika repair or overlay system can be used. Standard preparation (pre-wetting) shall be applied. When using a smoothing coat/pore filler over surface treated with Sika® FerroGard®-903, products such as SikaTop®-122 HS, Sikagard®-720 EpoCem® IN, Sika MonoTop®-122 F, SikaTop®-Seal 107 IN, etc. can be used. Cementitious levelling mortars shall only be used if there is a well prepared open textured surface that is completely cleaned of residue.
If other Sika cement based products are to be used, site trials are recommended to confirm preparation and suitability.
If non Sika cement based products are to be used, please contact the manufacturer technical department for confirmation of compatibility with Sika® FerroGard®-903 or undertake compatibility and adhesion site trials.
CLEANING OF TOOLS
Use water to clean application equipment.