Recommendations for Concrete Members Prestressed with Unbonded Tendons (ACI 423.3R-05)

Description

This report is an update to the previous ACI-ASCE Committee 423 report entitled “Recommendations for Concrete Members Prestressed with Unbonded Tendons(ACI 423.3R-96).” Since the publication of that report and the four previous reports that it replaced, many previous recommendations have been incorporated into ACI 318-02.These recommendations have been prepared to provide a comprehensive guide for design, materials, and construction for concrete members prestressed with unbonded tendons. Suggested revisions and additions to ACI 318 are also included in this report.

This report presents recommendations for design, materials, and construction for concrete structures prestressed with unbonded tendons that are commensurate with the safety and serviceability requirements of ACI 318-02.This report is a guide, and practitioners should use their judgment when applying its recommendations. This report is generally not intended for reference in a specification or a code.

The recommendations pertinent to design with unbonded tendons considered in this report include the design of beams,girders, slabs, continuous members, and details and properties of tendons and anchors and their protection from corrosionduring construction and throughout the life of the structure. The recommendations in this report are not intended forunbonded construction stages of elements using bondedtendons; for multistrand unbonded tendons used as external tendons; members subject to direct tension, such as tiebacks,cable stays, arch ties, or circumferential tendons for contain-ment structures; or ground-supported post-tensioned slabsfor light residential construction (PTI 2004).