Arup is the Engineer of Record for the Park Union Bridge, opened to pedestrians in July 2021, connecting the U.S. Olympic & Paralympic Museum to America the Beautiful Park and Downtown Colorado Springs. Called the rip curl for its cresting design, the footbridge was collaboratively shaped with Design Architect DS+R and spans 245ft over active rail lines. The 300 ton steel superstructure is designed to both integrate with the aesthetic vision for the museum and to minimize impact on rail operations during construction.
One of the key project successes for the design team was producing a design that struck a balance between achieving the aesthetic vision and minimizing the impact on the railroads below. From bridge inception, the designers leveraged their parametric 3-D work environment to communicate visually and explain crucial aspects of the bridge behavior among themselves and with key collaborators of the project team.
The design team collaboratively massed, rationalized, and managed the steelwork 3-D model in Rhino with a Grasshopper parametric plug-in. To realize this structure, the design team carried out global, modal, spectral, footfall, buckling analysis, and wind tunnel testing. When preliminary desktop studies showed a potentially divergent response to wind, Rowan Williams Davies & Irwin Inc. (RWDI), located in Ontario, Canada, was commissioned to design and build an aeroelastic model used to evaluate the wind-induced responses of the bridge. All analysis was completed in Oasys GSA, which linked parametrically to the 3-D steelwork model.
Building over railroads presents unique constraints both in design and construction. Maintaining railroad operation unimpeded during erection was a key driver in the design; the yard includes thirteen rail tracks with two through tracks that have freight train traffic of approximately ten trains per day. The bridge was erected 3 hours faster than the allowed 8 hour window.
- Course will award 1.0 hour of continuing education
- Diamond Review approved in all 50 states
- This webinar will be available as a recording.