#Post tension slab crack repair download#

Formulated, prepackaged grout has been an important advancement in materials technology however, segregation, pockets of soft grout and chloride contamination have resulted in tendon corrosion. Grouted Post-TensioningД«leed water, segregation of portland cement grout and improper grout installation can leave voids and residual moisture in many grouted structures. Environmental exposure to chloride or deteriorated grout pockets can cause localized corrosion.ДЄbove: Corrosion of post-tensioned strand adjacent to an anchor plate. In some cases, components of the post-tensioning system such as uncoated anchor plates or exposed strands in front of or behind the anchors are not protected before being embedded directly in concrete. As such, if post-tensioned steel is exposed to oxygen and moisture, corrosion can occur even in a chloride-free environment. Because the tendon is not in direct contact with concrete or grout, it is not protected by the alkalinity of these materials. Unbonded Post-TensioningД¬orrosion in unbonded post-tensioning systems can occur anywhere along the length of the tendon but typically occurs at low points where water can accumulate, at uncoated anchors, and at locations where less concrete cover is present. Post-tensioned steel is also more susceptible to damage from chloride-induced pitting corrosion, hydrogen embrittlement, and stress corrosion cracking.ДЄbove: Inspection of grouted (bonded) post-tensioned tendon. For example, special techniques are necessary to evaluate corrosion in encapsulated systems where corrosion can occur inside sheathed cables without exposure to external chlorides (as is typical for conventional reinforced concrete). Many investigation and repair techniques utilized for conventionally reinforced concrete are inappropriate for post-tensioned concrete. Grouted (bonded) post-tensioning systems have also experienced problems due to voids, water bleeding, and grouting problems.

Special Considerations for Post-Tensioned StructuresД®arly commercially available unbonded systems were susceptible to corrosion including paper wrapped, plastic push-through (stuffed) and heat-sealed (cigarette wrapped) sheathing systems due to their susceptibility to the ingress of water.

#Post tension slab crack repair download#

Our engineers and technicians have specialized knowledge and training in the deterioration and repair of post-tensioned concrete.Д¬lick here to download the 2019 Post-Tension Structures: Solutions for Repair & Protection.ДЄbove: Post-tensioned nuclear containment building required concrete repairs and FRP strengthening. Post-tensioned concrete is a unique structural system that is widely used to construct many types of structures such as bridges, parking structures, buildings and tanks.

Vector Construction is hard at work advancing the state-of-the-art evaluation, repair and protection of post-tensioned structures.