Adams Street Viaduct
The Adams Street viaduct crosses over 13 railroad tracks and runs directly alongside Chicago’s famed Union Station where 50,000 commuters pass each day. CMT was given the task of providing design phase services for the reconstruction of the viaduct amid the bustling activity in the heart of the country’s third largest city.
The reconstruction of the 260-ft. by 66-ft. structure consists of the removal and replacement of the deck, framing members, and columns. The existing caisson foundations will be reused. The new deck will be resurfaced with a bituminous overlay. In addition to the viaduct work, the project includes the reconstruction of the approach spans to an adjacent bascule bridge and roadway improvements to reduce high incidences of accidents.
The project’s proximity to one of the busiest railroad stations in the United States presents unique construction challenges that must be addressed in the design phase. No more than two railroad tracks may be unoperational at any time during construction to minimize disruption to Amtrak operations at its national rail hub. Removal of the existing deck will also expose the train passengers below to the elements, requiring the use of temporary covering.