Proj Overview

Project Overview

Replacing the I-25 Trinidad Viaduct in Colorado required spanning a variety of obstacles along a long, curved path. The resulting design used precast concrete tub girders and deck panels to span the Purgatoire River, three existing rail lines, a planned rail line, and four city streets.

The design features four bridges over the river (two for the interstate mainline and two on/off-ramp bridges), two viaducts carrying the interstate over the city streets and rail lines, and two on/off ramps connecting into the viaducts.

Precast Solution

The partial-depth, prestressed concrete deck panels played a key role in minimizing costs. The panels were used for both the interior panels and the deck overhangs, which varied up to 6 ft (1.8 m). They would have required costly formwork, especially for the deck portions within the curves. The overhang panels were supported over the exterior girder’s two flanges while cantilevering to match the overhang length.

 

Awards_
2012 PCI Design AwardsTransportation Award: Best Bridge with a Main Span over 150 Feet
2012 PCI Design AwardsHarry H. Edwards Industry Advancement Award
Project Team

Engineer

Tsiouvaras Simmons Holderness Inc. 

Contractor

Lawrence Construction 

Owner

Colorado Department of Transportation, Pueblo, CO 

Precaster

Plum Creek Structures

Key Project Attributes

  • The efficiency of precast concrete allowed for reduced costs, while also providing an innovative solution
  • Precast resiliency allows it to be competitive with other approaches that have been more traditionally used.

Project/Precast Scope

  • Bridge length: 855 ft (260 m)
  • Project cost: $79.5 million
  • Precast panels varied up to 6 ft (1.8 m).