IH-70 Ramp A
Life-Cycle Engineering Services | EXPANDED

Modjeski and Masters is pleased to announce the acquisition of structural engineering firm Summit Engineering Group, Inc. Our combined engineering prowess and respective technical skillsets will enable us to provide streamlined design and construction solutions to best meet client needs.

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back buttonSegmental Concrete Bridges

I-70/SH-58 Ramp 1 Flyover Design

| Wheatridge, CO

  • Client:

    Ames Construction Company
  • Service:

    Segmental Concrete Bridges
  • Status:

  • Overview

    The original interchange at I-70 and SH 58 was constructed in 1968. And since then, it has operated without the ramps from eastbound I-70 to westbound SH 58 and from eastbound SH 58 to westbound I-70. “The missing ramps have been a priority of the county for more than 20 years,” said Jefferson County Commissioner Kevin McCasky. “[The new ramps] figured prominently on Jeffco’s Countywide Transportation Plan completed in the 1990s and in all transportation plans since that time.”

    To address this issue, the Colorado Department of Transportation (CDOT) commissioned the design of new ramps to alleviate traffic on local arterials. As originally designed by another firm, the bridge featured curved, precast concrete girders with unique detailing. Working in concert with CDOT and the contractor, Summit Engineering Group (Summit) value-engineered the design to feature details and cross-sections similar to those developed for previous projects. This approach provided efficiencies to both the contractor and precaster, which helped meet the numerous construction challenges presented by the difficult urban site. The 11-span bridge crosses Clear Creek, a bike path, 3 traffic openings, eastbound and westbound I-70, and eastbound SH58. The structure includes the state’s longest span using constant depth, precast concrete U-girder construction.

    “The flyover bridge symbolizes the progress that has been made through regional collaboration between local, county, state, and federal officials,” said City of Wheat Ridge Mayor Jerry DiTullio. “This new flyover would not have been possible without the foresight of the entities involved and their commitment to enhancing accessibility for motorists through this corridor.”

    The interchange improvement project began in February 2007 and was completed nearly 3 months ahead of schedule. This project’s success and similar ones in Colorado over the last 5 years validates how Summit has advanced CDOT’s vision of developing precast concrete as a viable option for complex, long-span interchange construction. Summit was awarded the 2014 “Henry Hansen Industry Advancement Award” for this bridge by the Precast/Prestressed Concrete Institute. The award recognizes fresh, uninhibited concepts that hold the potential to move the industry to the next generation of technology for industry, materials, products, processes, and applications.
  • Description

    Tasks Performed
    • Value Engineering
    • Construction Engineering
    • Erection Engineering

    Bridge Geometry
    • Length of Main Span – 235 feet
    • Total Project Length – 2,115 feet
    • Lanes on Existing Structure – One Lane
  • Testimonial

    This interchange improvement project will greatly improve safety, mobility and access for commuters and members of this community. - Pam Hutton, Chief Engineer, CDOT
  • Credits

    Gregg A. Reese, PE (Project Principal)