Predicting the Bond Behavior of Prestressed Concrete Beams Containing Debonded Strands

Abstract

Static flexural tests were performed on prestressed concrete beam specimens made with debonded strands. A behavioral model based on the prediction of cracking in regions of the transfer zone of debonded strands was used to predict strand anchorage failures. Agreement between the test results and the prediction is excellent, demonstrating that a rational design method can be developed for prestressed beams with debonded strands. This research also shows that the currently required multiplier of 2.0 for the development length of debonded strands can be significantly reduced for some cases. Conversely, some dangerous and unsafe designs may be allowed by the current code. More appropriately, the provisions for anchorage of debonded strands may need revision.