Eltech Systems Corporation

Diamond Shamrock Corporation

Other

The Euclid Chemical Company

John E Bennett

Thomas A Mitchell

Gerald R Pohto

Joseph E Elliott

Barry L Martin

John J Bartholomew

Thomas J Schue

David E Harney

Carl W Brown, Jr

Neil W Stillman

Thomas R Turk

Donald S Novak

Rodney G Powers

Jacob R Blasius

Dale W Griffis, Ii

Russell J Bechkowiak

Claude M Brown

Dale W Griffis

The galvanic cathodic protection of steel embedded in concrete structures is enhanced by the utilization of a flexible composite anode assembly containing a sacrificial anode member. The anode member is at least partially covered by a matrix comprising an ionically-conductive material. The conductive material includes at least one electrochemical activating agent such as a mixture of lithium bromide and lithium nitrate and a compressible water-retaining mineral such as a phyllosilicate mineral. The presence of this mineral in the matrix increases the current delivered by the anode, thereby resulting in a greater level of cathodic protection, and a longer effective service life of the anode. Exfoliated vermiculite is a preferred phyllosilicate mineral and is present in an amount of between about 2% and about 15% by weight, based on the total weight of the matrix.

Composite anode for cathodic protection

The deterioration of reinforced concrete structures by galvanic corrosion adversely affects roads, bridges, parking garages and buildings that use reinforcing steel in their construction. Galvanic cathodic protection is typically provided for such reinforced concrete structures using embedded sacrificial anodes, such as zinc, aluminum, and alloys thereof. Disclosed herein is an anode assembly () for cathodic protection of a reinforced concrete structure. The assembly comprises at least one sacrificial anode member (). The anode member is covered with an ionically-conductive covering material () into which is bound an electrochemical activating agent at least partly covering the sacrificial anode member. One side () of the ionically-conductive covering material is configured to conform closely to a steel reinforcing bar. The conforming side has a non-conductive barrier () as an integral part of the covering material. Electrical connectivity is established between the anode member and a ferrous reinforcing bar () using conductive wires ().

Anode assembly for cathodic protection

A chorded zither including a self-supporting metal frame with separate and structurally independent sound board panels that can be easily interchanged and affixed to said frame to create different looking and sounding instrument configurations with the same basic instrument, including sound chambers that are deeper and greater in volume than those of the prior art.

Non-organic open-framed chorded zither/autoharp with multiple interchangeable sound chambers

The cathodic protection system of a concrete structure () uses sacrificial anodes such as zinc, aluminum and alloys thereof embedded in mortar. A humectant is employed to impart high ionic conductivity to the mortar in which the anode is encapsulated. Lithium nitrate and lithium bromide and combinations thereof are preferred as the humectant. The anode () is surrounded by a compressive, conductive matrix () incorporating a void volume between 15% and 50% to accommodate the sacrificial corrosion products of the anode. A void space of at least 5% of the total volume of the anode () may be provided opposite to the active face of the anode. Synthetic fibers such as polypropylene, polyethylene, cellulose, nylon and fiberglass have been found to be useful for forming the matrix. A tie wire is used to electrically connect the anode to the reinforcing bar.

Cathodic protection system

This invention relates generally to an electrically conductive valve metal mesh of extreme void fraction. More particularly the invention relates in a most important aspect to an application thereof for an electrode structure in such a way as to prevent the corrosion of steel, including reinforcing steel in concrete, by cathodic protection.

Expanded titanium metal mesh

A method of protecting reinforced concrete structures comprising of applying a protective cathodic coating containing a non-corroding metal and an electrochemically active material on concrete wherein the protective coating is formed by thermally spraying a mixture of said non-corroding metal such as a valve metal and said electrochemically active material. The coating may also be formed by applying a precursor of the electrochemically active material and a metal-containing layer to concrete, then anodically polarizing said metal layer to convert the precursor into an electrochemically active material.

Method of protecting reinforced concrete structures

A metal coating of typically a valve metal, especially a titanium metal coating, is applied by thermal spraying to the surface of concrete, most particularly steel-reinforced concrete. The metal such as titanium may be sprayed by any one of several thermal spraying techniques including flame spray, electric-arc spray, plasma spray, high-velocity oxyfuel spray, or detonation gun spray. The metal coating should be tightly adhered to the concrete and desirably will have a porosity to facilitate extensive coating of the metal itself, as well as facilitate any activation that may be needed for the metal. Such activation can be in the form of an electrochemically active material which allows the coating to function in electrochemically active form. One coating option is to apply a solution onto the spray-applied metal, then polarize the metal anodically to effect deposition of active material on the metal. Another option includes depositing electrochemically active material directly onto the concrete, then applying an adherent, electrically conductive overlay such as a titanium metal coating to the treated concrete.

Reinforced concrete structure

An anode for cathodically-protected steel-reinforced concrete is embedded in an ion-conductive overlay on the concrete structure. The anode comprises at least one sheet of highly expanded valve metal mesh having a pattern of voids defined by a network of valve metal strands connected at a multiplicity of nodes. This provides a redundancy of current-carrying paths through the mesh which ensures effective current distribution throughout the mesh even in the event of possible breakage of a number of individual strands. The surface of the valve metal mesh carries an electrochemically active coating. At least one current distribution member is welded to the valve metal mesh. The entire area of the structure to be protected, excluding non-protected openings for obstacles and the like, is covered by a single piece of the mesh, or several pieces in close proximity with one another.

Cathodic protection system for a steel-reinforced concrete structure

Expanded metal mesh and anode structure

The present invention resides in an apparatus for removing chloride ions from a reinforced concrete structure. The apparatus comprises an integrated anode assembly which includes an anode and an electrolyte, the anode being immersed in the electrolyte. The integrated anode assembly is flexible and conformable to the surface configuration of the concrete structure to which it is applied. Means are provided for removably adhering the integrated anode assembly to the concrete structure, conformed to said surface configuration, and for establishing an electric current between said anode and the reinforcement of said concrete structure.

Apparatus for the removal of chloride from reinforced concrete structures

Cathodic protection of a reinforced concrete structure utilizes a metal anode such as a zinc anode in combination with a pressure sensitive ionically conductive hydrogel in contact with at least a portion of the surface of the anode. Preferably, the anode and ionically conductive hydrogel are flexible and supplied in roll form. The combination may further include the addition of salt to the hydrogel as well as application to the metal-hydrogel combination of Type III cement. The cathodic protection may be carried out with or without a power source.

Method and apparatus for cathodically protecting reinforced concrete

A catalytically-coated valve metal reference electrode is used to measure the potential of reinforcing members in concrete in a system to cathodically protect the same.

Growing community of inventors

Chardon, OH, United States of America

John E Bennett