Prestressing strand for concrete structures and concrete structures containing such strand

摘要

In a prestressing strand for use in stressing a concrete structure, having one or more central core wires and a plurality of outer wires extending helically around the core wire the surface of at least the core wires is modified in order to increase the friction resistance to relative movement between the core wire and the outer wires. This strand is found to give more accurate stressing, where the conduit in the concrete for the tensioned wire is curved. The outer wires may also have modified surtaces. The modification may be mechanical indentations or surface conditioning treatment such as oxidation, etching, coating or deposition.