Precompressed concrete bar for reinforcing structural concrete - is stressed by embedded wires, with creep inducing compressive strain in reinforced member

摘要

A prestressed bar (1) of concrete or mortar is used to reinforce structural concrete members (3), replacing the conventional steel bar reinforcement in zones subject to tensile stresses, and effecting a reduction in the tensile cracking of the concrete. The bar is placed in a state of compression by pretensioned wires (4) dof high tensile steel or similar and then embedded in the member. A bond is promoted between the bar and the surrounding concrete, the time-proportional creep of the bar then inducing compressive strains in the member. The bar is fabricated on a stressing bed, a steel tube (1) containing the stressed wires being injected with concrete or mortar. The concrete may contain plastifying, air entraining or quick setting agents, or be heated.