PROCESS FOR REHABILITATING INTERNALLY REINFORCED CONCRETE BY REMOVAL OF CHLORIDES

摘要

A process for rehabilitation of internally reinforcedconcrete which comprises the temporary application of anadherent coating of an electrolytic material to surfaceareas of the concrete. Distributed electrode means,preferably a wire grid, is embedded in the adherent coat-ing. Voltage sufficient to develop a current of about 1-5amps/m is applied between the reinforcement and thedistributed electrode, to cause migration of chloride ionsfrom the concrete into the electrolytic coating. When thechloride content of the concrete has been reduced to adesired level, the voltage is discontinued and the electro-lytic coating and distributed electrode are removed. Ahighly preferred material for the adherent electrolyticlayer is cellulosic pulp, premixed with water or othersolution (such as calcium hydroxide) in a nozzle andsprayed onto the surface of the area being treated.Desirably, the distributed electrode is formed of a ferrousmaterial reactive with chlorine, to minimize the release offree chlorine gas into the ambient. Particularly fortensioned reinforcement, the process monitors polarizationof the tensioned steel to prevent hydrogen embrittlement.