Development of lightweight FRP bridge deck designs and evaluations

The focus of this study was to develop and analyze lightweight FRP bridge decks and determine their adequacy under AASHTO's HS25 loading case with minimum stringer spacings of five feet. Two different multicellular decks were designed and tested during this study. Both decks had fiber volume fractions of approximately 54% and weighed 14–15 lb/ft2 of deck area. Testing was performed to determine both the elastic and failure response at the component level and the elastic response at the system level. Theoretical correlation of stiffness was made via approximate classical lamination theory, and maximum transverse load distribution factors were predicted. In addition, several failure modes were identified and theoretically correlated to obtain applicable limit states based on the strain to failure approach. The study found that local resistance and force transfer across the joints were the areas of potential improvement. The remainder of the study showed adequate performance of the decks.