Patent ID: 6165346
Filing Date: 2000-12-26
Classification: C23F

Abstract:
A method for cathodic protection of a concrete structure comprising:providing a concrete structure having a layer of concrete and a steel member in contact with the layer of concrete;providing a sacrificial anode member;burying the anode member within the layer so as to be in contact with the concrete layer;the sacrificial anode member as provided and prior to being buried in the concrete layer comprising an anode body of an anode material which is covered on at least one surface thereof by a coating material which is carried by the anode body;the anode member being arranged such that, when the anode member is buried, the coating material is in contact with the concrete layer;the coating material being arranged to allow communication of current through the coating material and the concrete layer between the anode body and the steel member so as to provide cathodic protection for the steel member by an electrical potential between the anode body and the steel member which causes a current to flow through the concrete layer tending to inhibit corrosion of the steel member;the coating material comprising a solid material with a binder attaching the coating material to the anode body;providing in the coating material an additive different from the coating material itself which additive is a deliquescent material which is bound into the coating materials;causing the presence of the deliquescent material bound into the coating material to absorb sufficient moisture into the coating material to maintain conductivity around the anode body;and causing the presence of the deliquescent material to keep the interface between the anode body and the coating material electrochemically active to ensure that sufficient current is maintained between the anode body and the steel member during the life of the anode body to maintain said cathodic protection.