Static and fatigue performance of glass fiber-reinforced polymer (GFRP) web-core bridge deck sandwich panels: Experimental and numerical investigation

This study investigates the static and fatigue performance of glass fiber-reinforced polymer web-core bridge deck sandwich panels through experimental testing and numerical analysis. Tested deck specimens, incorporating reduced facing and web thicknesses to approximately 50% of full-scale decks, were designed to capture critical failure modes while maintaining realistic geometry and support conditions. The web-core sandwich panels, spanning 2 meters, demonstrated an ultimate load capacity exceeding 450 kN, which is more than 10 times higher than the factored highway wheel load defined by FLM4 (0.5*90 kN) and over 4 times higher the LM2 wheel load (0.5*200 kN), underscoring their potential for real-world bridge applications. The fatigue tests revealed multiple failure modes at high loads, with imperfections identified as the primary cause of failure. Finite Element Analysis supports the experimental results, showing that imperfections significantly reduce fatigue life, increasing local stresses and reducing the number of cycles. The buckling analysis suggested by the current European design recommendations was found to be conservative, as web buckling was not observed in tests. These findings underline the importance of accounting for imperfections in the design verifications, with further research needed to validate these conclusions for full-scale web-core sandwich bridge decks. • Downscaled web-core panels resisted > 450 kN, far above FLM4 (90 kN) and LM2 (200 kN). • Local dimples raised stress 1 . 4 × , cutting fatigue life up to 10 × . • Ply-level FEA matched tests; imperfections shifted failure modes, urging QC. • EU shear-buckling limits not seen in tests/FEA, suggesting conservative specs.