General presentation
Prestressed concrete General – Materials – Prestressing losses

Concrete is a particularly economical building material. Its compressive strength is high, but its tensile strength is mediocre and unpredictable. What's more, tensile failure is brittle: tensioned or bent parts can break suddenly as soon as the first crack appears.

Reinforced concrete corrects this shortcoming: tractions are taken up by steel reinforcements bonded to the concrete. However, the strength of the reinforcement can only be mobilized if the concrete cracks. Cracking considerably reduces rigidity and can affect durability. What's more, tensioned concrete only serves to encapsulate the reinforcement and hold it in place in the section, without contributing to the strength and rigidity of the structure. It constitutes...