Post-tensioning is a technique for concrete reinforcement. Post-tensioning tendons, which give the pre-tension of the steel ropes inside the channels and sleeves, are placed in the area before the concrete is placed. Then, once the concrete has strengthened, the ropes are tightly pulled or stretched and abutted against the outer edges of the concrete before the load is applied.
Prepress simply means that the steel is stretched (pulled or stretched) before the concrete supports service loads. The pre-precast, prestressed concrete is actually pre-stressed – the steel is drawn before the concrete is poured. Post-stressed concrete means that the concrete has been poured and then tension is applied; however, it is still stretched before the loads are applied, thus continuing to stretch.
The tensioning elements of the stretching method consist of high tensile strength rope bundles. After the cables (Cables) are tensioned, they are combined with the reverse lock system wedges that provide the transfer of the tension force to the structure.