This paper introduces the strutted box widening method (SBWM), a system that allows a two-lane segmental bridge to be designed and constructed so that it can be easily widened into a three- or four-lane bridge at any time in the future. This solution is attractive because widening only needs to occur if and when traffic volumes warrant it. Two examples demonstrate how the SBWM can be used to widen a variable-depth cast-in-place segmental bridge and a constant-depth precast segmental bridge. Design and construction considerations of the SBWM are addressed, and the advantages and disadvantages of the SBWM are outlined. Two particularly appealing potential applications are described.
