Reinforced hollow concrete article made watertight - by coating the mandrel of the mould with plastic prior to casting the concrete

摘要

Method comprises forming a thin layer of a plastic material of low elastic modulus on the core mandrel of the concrete mould, the layer, when it is thermosetting, being polymerised before the concrete is placed. Any reinforcing bars are located in the mould before insertion of the coated mandrel into the moulding cavity. Even if the concrete becomes fissured as a result of tensions and compressions the reinforcing bars will not become corroded from passage of fluid through the concrete article, since it will be protected by the flexible plastic coating.