Post tensioning is a concrete reinforcement technique. Post tensioning tendons which provides pre-tensionıng of steel ropes inside the plastic channels or couplers are placed in the forms before placing the concrete. After the concrete is strengthened, the ropes are swiftlypulled or stretched before applying the service loads and leaned against the outer edges of the concrete. The initial pressure simply means that the steel is stretched (pulled or stretched) before the concrete supports the service load. Prestressed precast is actuall pulled before the prestressed steel concrete is casted. Post-stressed concrete means that the concrete is casted and then stressed; however, it is still stretched before the Ioads are applied and stretching continues. Stretching elements of stretching method consist of rope bundles with high breaking strength. With variations of number of ropes and if needed, variations of rope diameters and quality of the steel, it is possible obtain a great diversity as rope units with breaking strength between 160 — 16.000 kN in standard units. Larger ropes can be manufactured for special applications. After stretching, the cables are wedged in an anchor which allows the tensile force to be transferred to the structure. The basis of the post tension method is type anchors.
Tensioning Anchors Post
Tension-type tensioning anchors help to anchor and stretch the ropes. These are designed according to the principle of anchoring each rope individually by means of compressors. The prestressing force is transferred to concrete by a rigid anchor plate. The spirals surround too much concrete in the zone behind the anchor plate. The tensile forces in the anchor zone should be met with an additional soft reinforcement. The reinforcement is determined by considering the shape and dimensions of the anchor plate as well as the dimensions of the end region. Stretching anchors can also be used as fixed anchors. In this case, the anchor head must remain stable during the tensioning process.
Post Tensioning On The Floor
Post-tensioning reinforccd concrete floors have become an important factot for all types of commercial and residential projectsa, and floor systems. There are two popular methods in flooring systems. Unidirectional pavement slabs, bi-directional pavement slabs, it has bcen detcrmined that it is economical in parking structure applications, apartment buildings, office buildings, hospitals, high or Iow office buildings and industrial buildings. With this technology, the problem of cracking which cannot be solved by traditional methods can be solved. Other factors contributing to the growth of post-tensioning construction work include
Post-tensioning systems are applied in bridge constructions, high-rise constructions, earth-rock anchors, parking constructions, underground constructions. Economic and safe solutions are reached in heavy loads and wide openings.