Corrosion protection techniques

Rak‐43.3312 Repair Methods ofRak 43.3312 Repair Methods of Structures II (4 cr)

E k SiEsko Sistonen

Some standards and publications related to corrosion protection techniques

• CATHODIC PROTECTION OF STEEL IN CONCRETE (ISO• CATHODIC PROTECTION OF STEEL IN CONCRETE (ISO 12696:2012)

• SFS‐EN 1504 (ten parts); Summarized in:• PRODUCTS AND SYSTEMS FOR THE PROTECTION AND 

REPAIR OF CONCRETE STRUCTURES.• DEFINITIONS REQUIREMENTS QUALITY CONTROL ANDDEFINITIONS, REQUIREMENTS, QUALITY CONTROL AND 

EVALUATION OF CONFORMITY.• PART 9: GENERAL PRINCIPLES FOR THE USE OF 

PRODUCTS AND SYSTEMSPRODUCTS AND SYSTEMS• Case Studies of Rehabilitation, Repair, Retrofitting, and 

Strengthening of Structures By Mourad M. Bakhoum, IABSE 20102010

• Durability of Engineering Structures: Design, Repair and Maintenance  By Jan Bijen, 2003y j ,

Principles and methods related to reinforcement corrosionEN 1504‐9:2008 (E)

i i i i• 7. Preserving or restoring passivity– 7.1 Increasing cover with additional mortar or concrete

– 7.2 Replacing contaminated or carbonated concrete

– 7.3 Electrochemical realkalisation of carbonated concrete

– 7.4 Realkalisation of carbonated concrete by diffusion

– 7.5 Electrochemical chloride extraction

Principles and methods related to reinforcement corrosionEN 1504‐9:2008 (E)

• 8. Increasing resistivity– 8.1 Hydrophobic impregnationy p p g

– 8.2 Impregnation

8 3 Coating– 8.3 Coating

• 9. Cathodic control– 9.1 Limiting oxygen content (at the cathode) by saturation or surface coatingg

Principles and methods related to reinforcement corrosionEN 1504‐9:2008 (E)

• 10. Cathodic protection– 10.1 Applying an electrical potentialpp y g p

• 11. Control of anodic areas11 1 A i i f h i f– 11.1 Active coating of the reinforcement

– 11.2 Barrier coating of the reinforcement

– 11.3 Applying corrosion inhibitors in or to the concrete

Simplified POURBAIX‐DIAGRAM / Tap Water / IronWater / Iron

Anodic protection

Protection by yAlkalization

Cathodic protectionCathodic protection

Simplified POURBAIX‐DIAGRAM / Clorides solution / Iron

7.3 Electrochemical Realkalisation

http://www.norcure.com/Realk.pdf

7.3 Electrochemical Realkalisation7.3 Electrochemical Realkalisation

Case: Pasila, Helsinki

7.4 Realkalisation of carbonated concrete by diffusion7.4 Realkalisation of carbonated concrete by diffusion

Not alkalied Coating

Not alkalied area area

Etki cs

7.5 Electrochemical chloride extraction

Vandex International Ltd 15/09/99, SBhttp://www.norcure.com/chloride.htm

Chloride extraction with renovation render / plaster / mortar)

M th d f t ti i f t i

metallic copper and/or copper compounds are added to the concrete mass, in which

Method for protecting reinforcement in concrete from chloride corrosion

mass the copper reacts with the chloride to form salts with a chloride content and of low solubility, thus substantially reducing the danger of steel corrosion caused by chloride. The copper or copper compound can also be brought into close contact with h f l i h f f i

Vandex International Ltd 15/09/99, SBhttp://www.google.com/patents/EP1290245B1?cl=en

the concrete, for example in the form of a repair mortar.

8.1 Hydrophobic impregnation8.1 Hydrophobic impregnation-based on Silanes or Siloxanes, or blends of these materialskth.diva-portal.org/smash/get/diva2:305538/FULLTEXT02

http://web byv kth se/shared/pdf/83 Johansson%20A %20http://web.byv.kth.se/shared/pdf/83_Johansson%20A.%20b84.pdf

8.2 Impregnation -water proof products (sealant)p p ( )-corrosion inhibitors

8.3 Coating

-Chemically and physically drying coatingsOrganic and inorganic coatings-Organic and inorganic coatings

9. Cathodic control9.1 Limiting oxygen content (at the cathode) by saturation or surface coating) y g

Creating condition in which potentiallyth di f i f t bl tcathodic areas of reinforcement are unable to

drive an anodic reaction

Advanced Concrete Technology 3: Processes, Volume 3edited by John Newman, B S Choo

10. Cathodic protection

http://www.norcure.com/Corrosion.pdf

Installation of Impressed Current Cathodic Protection System

http://www.cedd.gov.hk/eng/about/organisation/org_ceo_pm.htm

Cathodic protection with Titanium meshCathodic protection with Titanium mesh

Ted Kay: Assessment and renovation of concrete structures

http://www repairandprotect com/projects/pearl harbor/cathodic protection htmhttp://www.repairandprotect.com/projects/pearl_harbor/cathodic_protection.htm

Good anode materials:‐magnesium alloy(6 % Al, 3 % Zn, 0.15 % Mn)‐zinc‐aluminium (5 % Zn)‐titanium

http://www.accessscience.com/search.aspx?rootID=792458

http://www.norcure.com/Corrosion.pdf

11.1 Active coating of the reinforcement

Painting reinforcement with containing activei t A ti ti f i f t ipigments. Active coating for reinforcement is

coating which contain Portland cement orl t h i ll ti i t ( i ) hi helectrochemically active pigments (zinc) which

may function as inhibitors or which may providel li d th di t tilocalized cathodic protection

11.2 Barrier coating of the reinforcementBarrier coatings for reinforcement are coatingswith the aim of isolating it from the pore waterwith the aim of isolating it from the pore waterin the surrounding mortar or concrete

E C t d R i f t-Epoxy Coated Reinforcement-Galvanised reinforcing steel-Galvanised and Epoxy Coated Reinforcement-Galvanised and Epoxy Coated Reinforcement-Others

Concrete Structure Management:Guide to Ownership and Good Practice : pGuide to Good Practice Bulletin 44, FIB -Féd. Int. du Béton, 2008

11.3 Applying corrosion inhibitors in or to the concrete

Migrating corrosion inhibitors (MCI)

Volatile corrosion inhibitors (VCI)

http://www.cortecmci.com/

http://www.offshore-technology.com/contractors/corrosion/corroless

Other types of techniques

• non‐metallic FRP (Fibre Reinforced Polymer) bars and elements– Glass Fiber Reinforced Polymer (GFRP)

Carbon Fiber Reinforced Polymer (CFRP)– Carbon‐Fiber‐Reinforced Polymer (CFRP)• the risk of salt‐frost resistance

h i k f h lk li i• the risk of the alkali‐reaction

ACI 440.1R “Guide for the Design and Construction of StructuralConcrete Reinforced with FRP Bars”

FIB Task Group 9.3 – bulletin 40 “FRP Reinforcement in RCStructures”

http://aslanfrp.com/Aslan100/Resources/Aslan100a.pdf

Avoid combining idAvoid combining different metals

Avoid gaps