Article
Application of Stress Inequalities (Magnel Diagram) for a Prestressing Design with Cut Strands
Transportation Research Board 97th Annual Meeting
(2018)
Abstract
Prestressing is used to overcome the weakness of concrete in tension. If not properly controlled, tensile stresses develop in a section due to prestressing, which leads to cracking especially close to the beam ends. To control the stresses along with beam, it is necessary to change the prestressing force, strand eccentricity, or both. This is practically achieved by debonding, draping, providing cut strands, or a combination thereof. Debonding and draping are the most commonly used techniques with typical beam sections. However, in certain beam sections, the stress limits cannot be satisfied by implementing these two techniques. Debonding practices, guidelines, and specifications are well documented in literature. However, application of stress inequalities for evaluating the combined effect of debonding and cut strands during a prestress concrete bridge beam design is not documented. This article presents an example demonstrating the use of stress inequalities, in the form of a Magnel diagram, for prestressing design of a highway bridge beam with debonding and cut strands. Evaluation of the stress limits along the span is demonstrated using a prototype bridge.
Disciplines
Publication Date
January 7, 2018
Citation Information
Funda Yavuz, Upul Attanayake and Haluk M Aktan. "Application of Stress Inequalities (Magnel Diagram) for a Prestressing Design with Cut Strands" Transportation Research Board 97th Annual Meeting (2018) Available at: http://works.bepress.com/upul-attanayake/68/