Post-tensioned continuous voided concrete bridge decks are widely used in the Province of Ontario. These bridge deck designs are generally based on one-dimensional analysis. The longitudinal moments are usually calculated by considering the deck as a wide beam, and the transverse moments in midspan and at the intermediate supports are evaluated by treating those portions of the bridge as a transverse beam and a frame respectively.To examine more precisely this two-dimensional structural behavior under various loading conditions, the recently designed Highway 403 underpass at Winston Churchill Boulevard in Mississauga, Ontario, was analyzed using the readily available ICES STRUDL-II finite element program.This paper describes the ICES STRUDL-II finite element modelling and analysis procedures, the results obtained, and the comparisons with conventional calculations.