A hybrid sacrificial galvanic anode, an anodic system including the hybrid sacrificial anode, and a method of cathodically protecting steel reinforcement in concrete structures is provided. The hybrid anode provides initial steel polarization followed by long term galvanic protection without the use of batteries or external power supplies.

The present invention relates to a Z-type heterojunction photoanode film used for the photocathode protection of a reinforcing bar, the preparation method thereof and a method for the corrosion inhibition of mental materials from concrete structures in marine engineering by using the Z-type heterojunction photoanode film used for the photocathode protection of a reinforcing bar. The preparation method includes steps of preparing Fe.sub.2O.sub.3 on the conducting surface of a clean conductive substrate through the hydrothermal process, preparing Fe.sub.2O.sub.3-PANI composite photoanode film by depositing polyaniline on the surface of Fe.sub.2O.sub.3 through the electrochemical synthesis and preparing Ru-Fe.sub.2O.sub.3-PANI composite photoanode film on the surface of the Fe.sub.2O.sub.3-PANI composite photoanode film through the in situ chemical reduction method. The technical solution in the present invention can achieve highly effective photocathode protection of a reinforcing bar from concretes in marine engineering and improve the durability of concrete structures in marine engineering.

A cathodic protection system providing substantially complete coverage to individual steel-in-concrete units in a multi-unit structure. The system includes a power supply, an electronic circuit board, a header cable, anode wire in each unit connected to the header cable, an adhesive fiber mat in each unit, and a conductive coating in each unit.

Disclosed is an adhesive hydrogel containing a polymer matrix, water, and a polyhydric alcohol, wherein the polymer matrix contains a copolymer of a monofunctional monomer with a single polymerizable C—C double bond and a polyfunctional monomer with two or more polymerizable C—C double bonds, the monofunctional monomer contains a nonionic (meth)acrylamide-based monomer, and the polyfunctional monomer has a composition formula: C.sub.lH.sub.mO.sub.n, where O is an oxygen atom in an ether bond, l is an integer greater than or equal to 4, m is an integer greater than or equal to 6, and n is an integer greater than or equal to 0.

A cathodic protection system providing substantially complete coverage to individual steel-in-concrete units in a multi-unit structure. The system includes a power supply, an electronic circuit board, a header cable, anode wire in each unit connected to the header cable, an adhesive connector in each unit, and a conductor in each unit.

Sacrificial anodes for installing in an ionically conductive medium at an installation site containing metal requiring cathodic protection are formed by locating anode cores in a tray having dividing members defining a row of side by side chambers with each chamber containing a respective one of the anode cores and casting into the receptacle a covering mortar for the anode cores with each anode core receiving a coating at least partly surrounding the anode core with the connecting wire exposed. The mortar is cast to form frangible bridges between each anode and the next. The trays are stacked and transported to the site where the installer separates and individually installs the anodes into the medium.

Provided is an anticorrosion device that does not require the installation of electrical equipment and has no concern about loss of anticorrosion effect due to deterioration of the anode. An anticorrosion device that prevents corrosion of a metal material in a structure, including a thermoelectric power generation unit 10 configured to generate an electromotive force due to a temperature gradient, an anode unit 20 that is responsible for an anode reaction corresponding to the electromotive force, and a cathode unit 30 that is responsible for a cathode reaction corresponding to the electromotive force, in which the cathode unit 30 is a metal material (target metal) in the structure.

An array of anode assemblies for insertion at a plurality of locations in a gap between a section of a reinforced concrete structure and another solid structure is provided. Each anode assembly comprises an expandable member, an anode attached to the expandable member for protecting a steel reinforcement in the reinforced concrete structure, and an anode connector for interconnecting the array of anode assemblies. During use, each anode assembly of the array of anode assemblies is inserted into the gap, between the section of the reinforced concrete structure and the solid structure, at the plurality of locations. The expandable member of each anode assembly is configured to expand so as to press the anode into contact with a surface of the reinforced concrete structure.

The present invention relates to a Z-type heterojunction photoanode film used for the photocathode protection of a reinforcing bar, the preparation method thereof and a method for the corrosion inhibition of mental materials from concrete structures in marine engineering by using the Z-type heterojunction photoanode film used for the photocathode protection of a reinforcing bar. The preparation method includes steps of preparing Fe.sub.2O.sub.3 on the conducting surface of a clean conductive substrate through the hydrothermal process, preparing Fe.sub.2O.sub.3-PANI composite photoanode film by depositing polyaniline on the surface of Fe.sub.2O.sub.3 through the electrochemical synthesis and preparing Ru-Fe.sub.2O.sub.3-PANI composite photoanode film on the surface of the Fe.sub.2O.sub.3-PANI composite photoanode film through the in situ chemical reduction method. The technical solution in the present invention can achieve highly effective photocathode protection of a reinforcing bar from concretes in marine engineering and improve the durability of concrete structures in marine engineering.

In a method for cathodically protecting and/or passivating a metal section in an ionically conductive material such as steel reinforcement in concrete or mortar, an impressed current or sacrificial anode communicates ionic current to the metal section and a storage component of electrical energy which can be a cell, battery or capacitor is provided as a component of the anode. A current limiter is provided which prevents excess current draining the supply. This can be a semi-conductive device such as a transistor or diode is connected in the path from the anode to the metal section to limit the cathodic protection current to a value of the order of 1 milliamp. When a diode or similar device is used the current can be limited to the reverse leakage current of the diode.