Standards, Best Practice Guidances and Thresholds CONREPNET Workshop MW6 BRE, 24th April 2006 Standards, Best Practice Guidances and Thresholds Josse Jacobs Technological advisor BBRI 2006 04 24 CONREPNET, MW6 Workshop

EN 1504 Standards : 10 Parts 1 Definitions 2 Surface protection systems for concrete 3 Structural and non structural repair (soon) 4 Structural bonding 5 Concrete injection 6 Anchoring of reinforcing steel bar (project) 7 reinforcement corrosion protection (project) 8 Quality control and evaluation of conformity 9 General principles for the use of products and systems 10 Site application and quality control of the works 2006 04 24 CONREPNET, MW6 Workshop

Other EN Standards CEN/TS 14038-1 Realkalization prCEN/TS 14038-2 Chloride extraction (project ?) EN 12696 Cathodic protection of steel in concrete ??? Sprayed concrete for repair (project ?) 2006 04 24 CONREPNET, MW6 Workshop

Repair procedure according to 1504-9 Standard does not cover repair of concrete structures damage caused by fire repair defects of existing post-tensioned systems Requirements before repair Safety before, during and after works Assessment of defects and causes 2006 04 24 CONREPNET, MW6 Workshop

Defects and their causes 2006 04 24 CONREPNET, MW6 Workshop

Objectives and options Do nothing <==> demolition Factors to consider (general, health, structural, environmental) Choice of action Extent and cause of defects Future conditions Appropriate to chosen protection or repair option Principles Possible using EN 1504 or other standards 2006 04 24 CONREPNET, MW6 Workshop

Methods based on the principle 1 Protection against ingress (PI) 1.1 Impregnation 1.2 Surface coating with and without crack bridging ability 1.3 Locally bandaged cracks 1.4 Filling cracks 1.5 Transferring cracks into joints 1.6 Erecting external panels 1.7 Applying membranes 2 Moisture Control (MC ) 2.1 Hydrophobic impregnation 2.2 Surface coating 2.3 Sheltering or over cladding 2.4 Electrochemical treatment 3 Concrete Restoration (CR) 3.1 Applying mortar by hand 3.2 Recasting with concrete 3.3 Spraying concrete or mortar 3.4 Replacing elements 4 Structural Strengthening (SS) 4.1 Adding or replacing embedded or external reinforcing steel bars 4.2 Installing bonded rebars in preformed or drilled holes in the concrete 4.3 Plate bonding 4.4 Adding mortar or concrete 4.5 Injecting cracks, voids or interstices 4.6 Filling cracks, voids or interstices 4.7 Prestressing - (post tensioning) 5 Physical Resistance (PR) 5.1 Overlays or coatings 5.2 6 Resistance to chemicals (RC) 6.1 6.2 2006 04 24 CONREPNET, MW6 Workshop

Methods based on the principle Principles (reinforcement) Other solutions not excluded Principle Methods based on the principle 7 Preserving or restoring passivity (RP) 7.1 Increasing cover to reinforcement with additional cementitious 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 8 Increasing Resistivity (IR) 8.1 Limiting moisture content by surface treatments, coatings or sheltering 9 Cathodic Control (CC) 9.1 Limiting oxygen content (at the cathode) by saturation or surface coating 10 Cathodic Protection (CP) 10.1 Applying electrical potential 11 Control of Anodic Areas (CA) 11.1 Painting reinforcement with coatings containing active pigments 11.2 Painting reinforcement with barrier coatings 11.3 Applying inhibitors to the concrete Note: Some of the methods may make use of products and systems that are outside the scope of the EN1504 series. 2006 04 24 CONREPNET, MW6 Workshop

After repair Record of repair works Instructions on inspection and maintenance to be undertaken during the remaining design life of the repaired part of the concrete structure 2006 04 24 CONREPNET, MW6 Workshop

Selection overview Not all methods covered by standards 2006 04 24 CONREPNET, MW6 Workshop

Performance characteristics (EN1504-2) Many tests, Criteria/test in function of Principle and method Several test related to durability of material and to protection of substrate (permeability, frost). 2006 04 24 CONREPNET, MW6 Workshop

Performance characteristics (prEN1504-3) Material characteristics Compressive strength, Chloride content, adhesive bond, Shrinkage/expansion Durability of the material Carbonation resistance, thermal compatibility Other Elastic modulus, skid resistance, thermal expansion, Capillary absorption Chloride ion ingress : only for special applications 2006 04 24 CONREPNET, MW6 Workshop

Performance characteristics (EN 1504-4) Tests on suitability for application, adhesion, material charcateristics Durability of the product: Thermal cycling Moisture cycling 2006 04 24 CONREPNET, MW6 Workshop

Performance characteristics (1504-5) 3 purposes for injection Durability characteristics Adhesion after thermal and wet-drying cycles, compatibility with concrete, sensitivity to water (expansion) 2006 04 24 CONREPNET, MW6 Workshop

Other repair materials Anchoring (EN 1504-6) Corrosion (1504-7) Under development 2006 04 24 CONREPNET, MW6 Workshop

Conclusions BUT Repair can be designed (1504-9) Materials can be evaluated (1504-8) Repair can be evaluated (1504-10) PBI are possible BUT No reflections on repaired structures What about performances after aging What about behaviour of the repaired structure 2006 04 24 CONREPNET, MW6 Workshop