Post Tension Cable Slab Foundation

Errors that lead to cracks in post tensioned slabs.

Post tension cable slab foundation.

Cables are arranged as indicated by the engineer and chaired to run through the center of the slab. Campbell the post tension cable system for concrete slab foundations that has and is replacing the standard steel rebar system has a fundamental flaw. As a result it s best to construct a post tensioned slab giving the slab the strength to resist stresses caused by the soil. Commercial foundations will have much more steel.

Foundation repair of post tension foundation including cables. The home builders theory is that they can achieve a minimum of 50 psi pounds per square inch compression throughout the slab and most importantly at the middle of the. A post tension slab is a slab of concrete that has been pre stressed using a specific method to increase the strength of the concrete. When errors are made on site during the post tensioning process the ability of the reinforcement to prevent cracking is decreased.

The post tensioning institute designed post tensioned foundations. Construction of post tensioned slabs on grade is very similar to using reinforcing steel except for the tensioning step. Many modern homes are built on post tension slab concrete. Several methods exist for pre stressing concrete with post tensioning being a very common one.

For residential construction tendons at 48 inches on center are common. The first edition of the post tensioning manual was published in 1972 and as of the time of this writing 2018 they are up to their 6th edition. We specialize in elevated and slab on grade post tensioning and post tension repair work for both commercial and residential applications in dallas fort worth arlington keller plano mansfield and throughout the dfw metroplex texas oklahoma colorado louisiana and new mexico. Post tensioned slabs are thinner and lighter which have trickle down effects on the both the building gravity and lateral force resisting systems including columns shear walls and foundations.

A primer a basic concept to understand is that concrete is strong in compression and weak in tension. This tension makes the concrete slab and foundation much stronger than concrete without reinforcement and helps reduce cracking. Flexural cracks develop when.