TREATMENT PROCESS FOR CONCRETE

• US 20110168571A1
• Filed: 03/21/2011
• Published: 07/14/2011
• Est. Priority Date: 03/16/2005
• Status: Active Grant

• Current Assignee: Adrian Roberts, Gareth Glass, Nigel Davison
• Original Assignee: Adrian Roberts, Gareth Glass, Nigel Davison
• Inventors: GLASS, Gareth, DAVISON, Nigel, ROBERTS, Adrian
• Granted Patent: US 8,349,166 B2
• Time in Patent Office: Days
• US Class Current: 205/734
• CPC Class Codes: C23F 13/02 cathodic; Selection of conditions, parameters or procedures for cathodic protection, e.g. of electrical conditions
• CPC Class Codes: C23F 13/06 Constructional parts, or assemblies of cathodic-protection apparatus
• CPC Class Codes: C23F 13/16 Electrodes characterised by the combination of the structure and the material
• CPC Class Codes: C23F 2201/02 Concrete, e.g. reinforced
• CPC Class Codes: C23F 2213/21 combining at least two types of anodic or cathodic protection
• CPC Class Codes: C23F 2213/31 Immersed structures, e.g. submarine structures
• CPC Class Codes: E04C 5/015 Anti-corrosion coatings or treating compositions, e.g. containing waterglass or based on another metal coating of discrete reinforcing elements C04B20/10

Abstract

A single anode system used in multiple electrochemical treatments to control steel corrosion in concrete. The anode system comprises a sacrificial metal that is capable of supporting high impressed anode current densities with an impressed current anode connection detail and a porous embedding material containing an electrolyte. Initially current is driven from the sacrificial metal (1) to the steel (10) using a power source (5) for converting oxygen and water (14) into hydroxyl ions (15) on the steel and drawing chloride ions (16) into the porous material (2) around the anode such that corroding sites are moved from the steel to the anode restoring steel passivity and activating the anode. Cathodic prevention is then applied. This is preferably a sacrificial cathodic prevention which is applied by disconnecting the power source and connecting the activated sacrificial node directly to the steel.

Claims

1. A method of protecting steel in concrete that comprises using an anode and a source of DC power and a temporary impressed current treatment and a low current preventative treatment wherein

the temporary impressed current treatment is a high current treatment using the source of DC power to drive current off the anode to the steel to improve the environment at the steel and

the low current preventative treatment is applied to inhibit steel corrosion initiation after the application of the temporary impressed current treatment and the same anode is used in both treatments and

the anode comprises a sacrificial metal element that undergoes sacrificial metal dissolution as its main anodic reaction.

2-39. -39. (canceled)