Development of Local Deflection Limit State for Multicellular FRP Bridge Decks

Local deflection responses and simple mathematical equations of a multi-celluar FRP deck have been developed and presented herein. The proposal limit state for local deflection is based on experimental and numerical modeling data of various types of FRP bridge decks. The local deflection of FRP bridge decks has been derived and verified for structural safety reasons. For example, excessive deck curvature can lead to wearing surface cracking and potential deck deterioration. The proposed limit state can be an integral part of FRP deck design procedure. Using a single span beam model, local deflection limit state is validated by comparing with the data for deck flange deflection under HS 25 truck load conditions. The data are further validated from finite element analysis. Local deflection limit state is proposed to be one percent of the distance between two contiguous webs of a deck. The average percent fixity of top flange of multicellular FRP decks is taken as 15-20% while computing for local deflection.