Title: Advanced Composite Demonstration Bridge Deck

Author(s): Srinvasa L. Iyer

Publication: Symposium Paper

Volume: 138

Issue:

Appears on pages(s): 831-852

Keywords: anchorage (structural); bridge decks; cable; composite materials; fiberglass; glass; post-tensioning; prestressing; slabs; stresses; tests; Construction

DOI: 10.14359/4239

Date: 9/1/1993

Abstract:
A 30-ft span, 17-ft wide bridge was constructed in Rapid City, South Dakota, in the summer of 1991 to demonstrate the application of graphite and fiberglass cables for prestressing bridge decks. This bridge was designed by consultants and built by local contractors with the technology developed at the South Dakota School of Mines and Technology. Paper deals with the construction phase, testing, and monitoring of the bridge from September, 1991 to December, 1992. Post-tensioning bonded method was used for prestressing the bridge deck in the transverse direction, whereas nonprestressed reinforced reinforcement was used in the longitudinal direction as distributors. The slab thickness was 7 in. and was supported by three longitudinal girders. One-third of the bridge was prestressed with S-2 glass cables, while the second one-third was prestressed with graphite cables and the last one-third was prestressed with steel cables. Special anchorages were used for prestressing the cables. Electrical and slip gages were used to monitor the stresses in the cable and deck. After the bridge deck was constructed, it was loaded for static and dynamic loading before it was opened for traffic. Paper addresses the test methods and quality control for bridge cables, including the design guidelines for using new materials for the bridge decks. The actual test data for the bridge was compared with the design data and found very comparable in this project. This bridge project demonstrates the feasibility of using advanced composite cables for prestressing bridge decks. The information gained through the design, construction, and monitoring of this bridge will help provide guidelines for the design and construction of future bridges.