A Study of Pretensioned High Strength Concrete Girders in Composite Highway Bridges- Design Considerations

Recent developments have made concrete with strengths up to 12,000 psi commerically available for construction of pretensioned highway bridge girders. The implementation of this material has preceded the full understanding and documentation of its behavior and effect on the design of bridge structures. Therefore, a review of code, practice, and the literature is necessary for high strength concrete to be used safely and efficiently in pretensioned bridge girders.

Selected girder cross-sections are reviewed and determined their sensitivity to different design parameters and their effectiveness with the use of high strength concrete than some sections currently in use. Several factors are identified that limit the design potential of some sections.

AASHTO and ACI codes are reviewed for application to high strength concrete. Test data and analytical studies related to the use of high strength concrete are also reviewed.

Based on the review of codes, literature, test data, and additional analytical studies, proposals and recommendations are made regarding the design of pretensioned high strength concrete bridge girders.