The Colorado Department of Transportation and Granite/RLW Joint Venture, the contractor for the Grand Avenue Bridge project, were presented with the Rocky Mountain Chapter ACI Excellence in Concrete Award in the infrastructure category. The projects submitted for this award were judged on the following criteria: innovative construction techniques or solutions, innovative use of materials, engineering merit, architectural merit, sustainability, resilience, functionality and end use suitability.
“The Grand Avenue Bridge project was the most significant CDOT project in Region 3 since the completion of Interstate 70 through Glenwood Canyon in 1991,” said Gaylen Stewart, construction manager for the Grand Avenue Bridge project. “The design and use of the concrete was planned into the design primarily to maintain design continuity throughout the historic downtown area, but also played a central role to the structural elements across the project site.”
The Grand Avenue Bridge traffic bridge and the Pedestrian Bridge and surrounding infrastructure required 21,398 tons of concrete both paving and structural and 3,373 tons of asphalt. The entire concrete formed superstructure of the downtown section of the traffic bridge was constructed during the closure of Grand Avenue.
Replacing the aging and “functionally obsolete” 50’s era highway structure required innovative solutions from both the engineers and contractors during a two-and-a-half-year design period. The bridge consists of two separate structures married with an expansion device. The structure was cast in place concrete deck that varies from 9” at the edge, to a radially thickened maximum of 3’ 3” in the middle of the deck, with 51 coffers on three lines. The location - relatively small downtown spans, conventional reinforcing steel, prefabricated formwork and simple low-height falsework aided in reducing costs and construction time. The designs provided options for lighting fixtures, textures and reveals.
The new pedestrian bridge, included in the scope of the project is a connection that ties the north and south downtown districts together with an elegant, accessible concrete structure. The path has four bump outs and two canopies for the public enjoy views of historic downtown Glenwood Springs, as well as the natural beauty of Glenwood Canyon and the Roaring Fork Valley.
Aesthetic concrete design features were considered throughout the project including: the highway and pedestrian bridges, the highway bridge barrier, the pedestrian stair cases, elevator building, pedestrian underpass and a pedestrian plaza. Concrete was designed to develop an enhanced experience and reflect the history of the area. This level of detail helps to contribute to a redevelopment of the historic downtown Glenwood Springs. Contextual design contributed to making these bridges structures that have grown out of the form, materials and colors of the city. The design strengthens downtown Glenwood as the core of the community and gateway to the Roaring Fork Valley.