GFRP Bridge Deck Systems for Skewed Bridges: An Analytical Investigation on Deck Orientation

Glass fiber reinforced polymer (GFRP) bridge deck systems have been used increasingly for rehabilitation efforts and new construction, particularly for bridge applications requiring high strength, low self-weight, or good fatigue and environmental resistance. GFRP decks are typically constructed by joining pultruded plates and shapes with mechanical fasteners or structural adhesives. This yields a deck system that has one dominant strong direction for flexure. When such a system is installed, the deck panels are placed such that the strong direction is perpendicular to the supporting girders. On skewed bridges this orientation is neither practical nor efficient in terms of construction time. However, orienting the panels at the angle of skew effects behavior of the deck panel in terms of stiffness and how load is distributed to the girders. In this study, the finite element method is used to evaluate the correlation between low profile GFRP deck panel orientation angle and response. Thick shell elements with equivalent elastic stiffness coefficients were calibrated based on previous experimental studies in the principal fiber directions. Five skew angles are considered in the analysis while monitoring the transverse load distribution between girders, mid-span deflections, and principal strains. Practical issues related to the skewed installation will be discussed.