An experimental and analytical investigation is conducted regarding the behavior of Ontario-type reinforced concrete bridge decks. A full-scale bridge deck (both cast-in-place and precast), detailed in accordance with the Texas State Department of Highways provisions for Ontario-type decks, and having about 60% of the reinforcement required by the current AASHTO code, performs well under current AASHTO design load levels. Under service and overload conditions (about three times the current AASHTO design wheel load), the behavior of the deck slab is essentially linear. Membrane forces do not noticeably affect the performance of the bridge prior to deck cracking. After cracking, significant compressive membrane forces are present in the deck, and could significantly increase its flexural capacity. Detailed finite element models of the specimen are developed for both the cast-in-place and precast panel deck cases. Cracking of the deck is followed using sequential linear analyses with a smeared cracking model. Analytical predictions agree well with experimental results.