Abstract: A high integrity container having a three-layered structure that is suitable as a container for use in storage and disposal of radioactive wastes or industrial wastes can be fabricated by casting a concrete lining as an inner layer on the inner surface of a metallic vessel as an outer layer, reinforcing the concrete lining with a reinforcing material and strengthening the concrete lining with an impregnant, and polymerizing and curing the impregnant layer that is formed as an intermediate layer between said metal drum and the concrete lining.

Abstract: A multiplex design container, is herein disclosed, that comprises a metallic vessel as an outer layer, a concrete lining as an inner layer that is formed on the inner surface of the metallic vessel and which is reinforced with a reinforcing material and strengthened with an impregnant, and a polymerized and cured impregnant layer as an intermediate layer that is formed between said metallic vessel and the concrete lining.

Abstract: A polymer-impregnated concrete product is obtained by placing a concrete mix in a frame capable of withstanding high temperature and high pressure in such a manner as to form therein a hollow portion, molding the concrete mix to obtain a concrete article containing a hollow portion therein, causing the concrete article as held in a tightly closed state in the frame to be cured by application of heat, subjecting the concrete article, as retained in the frame, to treatments for drying and deaeration, then supplying a monomer preparation to the hollow portion of the concrete article, applying pressure to bear upon the concrete article thereby causing the monomer preparation to be diffused into the fine voids in the concrete article, and heating the concrete article in situ thereby allowing the diffused monomer to be polymerized.

Abstract: Concrete products possessing properties far excelling those of conventional autoclaved concrete products are obtained by placing fresh concrete mix in molding frames adapted to withstand elevated temperatures and increased pressure, closing the filled molding frames airtightly, and heating the molding frames and the concrete mix held therein while inhibiting completely the leakage of water from within the molding frames and thereby allowing the concrete mix inside the molding frames to be cured while in a state of being maintained at elevated temperatures under increased pressure.