AbstractSteel plate girders are considered a viable solution for the construction of medium- to long-span bridges. Despite their many advantages, various concerns have been raised regarding their maintenance due to the potential of fatigue crack initiation at welded details, accelerated corrosion in thin webs, and trapped debris around stiffeners. The use of rolled beams, on the other hand, can be very beneficial because they require much less maintenance. However, they are limited in size, which imposes constraints on their use to relatively short-span bridges due to deflection requirements. In this study, the behavior of the double composite superstructure system was investigated. The system comprises rolled beams in combination with a reinforced concrete slab, resting on the bottom flanges of the beams, to allow for longer spans to be built using rolled beams. To assess the full potential of double composite bridge systems, an analytical formulation, validated through numerical finite-element analysis, was developed to capture the full nonlinear behavior of the bridges. The effect of some parameters relevant to the performance, such as the use of prestressing tendons and ultrahigh-performance concrete, was investigated. The analysis results showed a substantial reduction in deflection for the double composite bridges over their single composite counterparts. Similarly, a significant increase in the moment capacity was also shown when the double composite sections were used. The finite-element modeling approach was used to reflect on the localized response of a selected bridge. The analysis procedure outlined in this study could be applied for the design and assessment of double composite bridges and could be used to determine the viability of using such a system for the construction and rehabilitation of new and existing bridges.