Bending of FRP Bridge Deck Under the Combined Effect of Thermal and Vehicle Load

Abstract

Fibre reinforced plastics (FRP) composite materials have been introduced in bridge engineering as it offers easy installation, lightweight and corrosion resistance. In the present investigation, FRP bridge deck has been modeled using the ANSYS 14.0 software package. A finite element computer code has also been developed for the analysis of the bridge deck. The deck has been formulated as a laminated composite plate stiffened with closely spaced laminated stiffeners having box configuration. The first order shear deformation theory has been applied. The box stiffener induces a considerable amount of torsional rigidity due to its closed attachment with the plate. Therefore, the torsional rigidity of the stiffener has been calculated by considering the stiffener cross section as a hollow box configuration. The bridge deck model has been developed as one plate at top and another plate at bottom with vertical blade stiffeners placed between the horizontal plates using ANSYS 14.0. The temperature gradient between the top and the bottom surfaces of the FRP bridge deck is developed due to low thermal conductivity of FRP materials and hollow section which gives rise to a very high thermal stress. The thermal load on the deck has been considered to be varying linearly through the depth of the deck. The combined effect of vehicle load and temperature gradient through the thickness on the bending behaviour of the FRP deck has been studied in the present analysis. The present formulation has been validated by comparing the obtained results with those available in the published literature.