Title:
PT Grout: Bleed water voids
Author(s):
Morris Schupack
Publication:
Concrete International
Volume:
26
Issue:
8
Appears on pages(s):
69-77
Keywords:
Post-tensioning; prestressing steel; corrosion; ducts; bond; water retentive; thixotropic; failure
DOI:
Date:
8/1/2004
Abstract:
Portland cement grout has been used to fill post-tensioning (PT) ducts. Incidents of PT corrosion failures reported around the world can often be attributed to unexpected grout voids caused by water separation from the liquid grout solution. Early users of PT cement grout recognized, but did not adequately deal with, sedimentation (bleed). External visual observations could not detect how well the ducts and anchorages were filled. This article presents the past history of PT grouting, and suggests further research to determine if common practices are based on facts or myths.