The minimum thickness of steel deck plates was changed from 12 mm to 16 mm for fatigue durability, but the effect of deck thickness on load-carrying capacity has not been quantitatively investigated. Therefore, the effects of deck steel plate thickness and the number of longitudinal and transverse ribs on load-carrying capacity were evaluated by FEA. As a result, the load-carrying capacity did not decrease significantly even when the thickness of the steel deck plate was increased and the number of U-ribs was decreased. In addition, although the deflection of the steel deck plate increased when a wheel load was applied, it was confirmed that the deflection limit specified in the Japanese specifications for highway bridges was satisfied.
