Central Park Boulevard Bridge
Matrix performed bridge type selection studies and designed a new viaduct structure to carry Central Park Boulevard (CPB)—a major arterial connecting areas south and north of Sand Creek—over intervening features. The viaduct will ultimately carry six lanes of CPB traffic over Smith Road, a UPRR mainline track, RTD’s East Corridor light rail line, and Sand Creek. The structure will also span the proposed Sand Creek Trail to be located on the north bank of the creek.
Because of the overall size and cost of the structure, Matrix was asked to evaluate the feasibility of building the bridge with only four traffic lanes with provisions for widening the structure to six lanes in the future as traffic volumes warrant.
Matrix developed four alternative structure types with three feasible span configurations. The Matrix team then evaluated each alternative in order to identify the most cost effective and aesthetically pleasing solution for this highly visible bridge. The ability to easily widen the bridge in the future was an important criterion in the evaluation. Span lengths ranged from 100 to 220 feet. The five alternatives studied included:
- A five-span continuous cast-in-place concrete box-girder
- A five-span spliced, continuous precast/post-tensioned concrete U-girder
- Two alternative five-span continuous welded steel plate-girders
- A six-span spliced, precast concrete bulb-tee girder
Based upon the evaluation, the five-span spliced, continuous precast/post-tensioned concrete U-girder alternative was recommended for construction. The overall bridge length is 906 feet, and estimated construction cost for the initial four-lane section is $8,551,700. Matrix completed the final design; the project is currently under contract for construction support.