Process of electrochemically re-alkalizing reinforced concrete

US4865702A · kind A · utility

Assignee

• Norsk Averflate Teknikk A/S (NOT) · NO

Inventors

• John Miller · Green Valley, US
• Oystein Vennesland · Trondheim, NO

Key dates

• Filing date: Jan 11, 1988
• Grant date: Sep 12, 1989
• Expiry date: Jan 11, 2008

Classification

• Technology area (CPC E): Fixed Constructions
• CPC primary: E04G23/02
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A process is disclosed for re-alkalizing carbonized reinforced concrete. An electric current is impressed between adjacent areas of concrete, one of which has become carbonized with consequent loss of pH, and the other of which is adequately alkaline in pH. The impressed voltage causes a migration of hydroxyl ions from the higher pH region to the lower pH region, to effect an increase in pH of the carbonized region to a satisfactory level. The region of high pH concrete may be either non-carbonized areas of the original concrete or a temporarily applied layer of an alkaline electrolyte.