Pre-Stressed Concrete Beams

Pre-Stressed Concrete Beams
Pre- stressed concrete beams are beams in which the concrete is entirely in compression with tensile forces taken by steel tendons. These are fabricated to produce a compression more than the expected tension under loading conditions. High strength steel tendons are stretched while the beam is cast over them. Then, when the concrete has cured, the tendons are slowly released and the beam is immediately under eccentric axial loads. This eccentric loading creates an internal moment, and, in turn, increases the moment carrying capacity of the beam. They are commonly used on highway bridges.