||Implementation of a Prestressed Inverted T-Beam System
Kevin K. McGhee
Associate Director for Pavements
A Virginia Tech research team will work with VDOT to design a new bridge on U.S. 360 over the Chickahominy River using prestressed inverted T-beams and a reinforced, cast-in-place concrete topping. The team will optimize the design of two similar Minnesota bridges built in 2005. Using precast elements reduces the time needed to construct formwork, tie reinforcing steel and place concrete on site, thus cutting traffic congestion as well.
The researchers will investigate the advantages of using 0.7-inch diameter prestressing strands in the prestressed girders to determine their use in the final design of the bridge. The reinforced cast-in-place topping of the inverted T-beam is deeper than typical adjacent member systems. This design will control or eliminate reflective cracking between members, providing more durability than structures with thin, unreinforced overlays. This system also will reduce maintenance costs compared to adjacent box-beams and voided slab systems.