Proj Overview

Project Overview

Replacement of two deteriorating three-span bridges on a major interstate was required for this design-build project. Using traditional construction methods, interstate traffic would have been rerouted over a 90-mile detour. To limit disruptions, accelerated bridge construction techniques were mandated.

Precast Solution

Use of precast concrete AASHTO Type II girders with a lightweight concrete deck met the requirements for the two-span bridge. The shallow-depth girders minimized fabrication time and allowed an increase in the bridge’s vertical clearance without changing the interstate profile. Girder span was increased by use of the lightweight deck, further minimizing construction time. A hydraulic jacking system was used to slide the main span and approach slabs in place, keeping closure time to a maximum of 7 hours.

This is the first bridge replacement project in the U.S. in which the approach slabs were slid in along with the main span. The accelerated construction system and use of precast girders helped reduce the overall project cost. The construction cost was approximately 60% of the engineer’s estimate.

 

Awards
2011 Design AwardsBest Bridge with a Main Span from 76 to 149 feet
Project Team

Engineer

Michael Baker Jr. Inc., Midvale, Utah 

Contractor

Ralph L. Wadsworth Construction Company, LLC, Draper, Utah 

Owner

Utah Department of Transportation 

Precaster

ENCON, Denver, CO

Key Project Attributes

  • Use of precast concrete AASHTO Type II girders with a lightweight concrete deck limited traffic disruptions.
  • The shallow-depth girders minimized fabrication time and allowed an increase in the bridge’s vertical clearance.
  • This is the first bridge replacement project in the U.S. in which the approach slabs were slid in along with the main span.
  • The accelerated construction system and use of precast girders helped reduce the overall project cost.

Project/Precast Scope

  • Deck area: 3,700 ft2
  • Bridge length: 82 ft 6.5 in.
  • Bridge width: 44 ft 10 in.
  • 14 80-ft 8-in. AASHTO Type II prestressed concrete girders