Evaluation and Analysis of Decked Bulb T Beam Bridge

Prestressed beams have been a popular beam of choice for building highway bridges in the Midwest since the early 1960s. Although these beam types are economical and are proven to carry traffic loads well, they are starting to show signs of distress, mostly from corrosion of the steel reinforcement that is caused by moisture contaminated with salt and chlorides. Salt used for deicing roadways causes chlorides to penetrate the beams and cause the steel reinforcement and prestressing strands to corrode. Some states use pre-stressed box beams because of their efficient cross section and small beam depth to span ratio. Today, many of these structures are reaching the end of their service life, mainly because of corrosion of the steel reinforcement. In the harsh environment of the Midwest, where bridges are exposed to many freeze thaw cycles and deicing salts it would be beneficial to have a bridge structure free from corrosion, easy to inspect, and a service life at least double that of current structures. Also, since mobility of the traveling public is a very important consideration when building or rehabilitating bridges, there is a need to develop a beam type that can be built using accelerated bridge construction techniques. The objective of this project is to analyze and evaluate the decked bulb T beam (or decked I beam) as a viable replacement for the side-by-side box-beam bridge. The project description uses the term bulb T beam as a general description of an I beam shape, with a wide top flange that can serve as a deck surface. For this type of beam to be a viable replacement to a box beam, it must have a very robust cross-section designed to have a shallow depth to span ratio, which makes it very different than the standard American Association of State Highway and Transportation Officials (AASHTO) section used by some states. The use of a bulb T beam cross section would eliminate inherent problems associated with the ability to inspect and repair box-beam type structures. The Bulb T beam cross-section will provide enough space at the section bottom for ease of periodical inspections and maintenance of critical elements, such as beam web and the suffit of the bridge deck slab.


  • English


  • Status: Completed
  • Funding: $415500
  • Contract Numbers:


  • Sponsor Organizations:

    Iowa Department of Transportation

    800 Lincoln Way
    Ames, IA  United States  50010

    Michigan Department of Transportation

    Van Wagoner Building
    425 W. Ottawa Street
    Lansing, MI  United States  48909

    Minnesota Department of Transportation

    Transportation Building
    395 John Ireland Boulevard
    St Paul, MN  United States  55155

    Oregon Department of Transportation

    355 Capitol St. NE
    Salem, OR  United States  97301-3871

    Wisconsin Department of Transportation

    PO Box 7910
    4802 Sheboygan Avenue, Room 104
    Madison, WI  United States  53707-7910
  • Project Managers:

    Clover, Andre'

  • Performing Organizations:

    Lawrence Technological University

    21000 West Ten Mile Road
    Southfield, MI  United States  48075
  • Principal Investigators:

    Grace, Nabil

  • Start Date: 20110919
  • Expected Completion Date: 0
  • Actual Completion Date: 20150430
  • Source Data: RiP Project 29835

Subject/Index Terms

Filing Info

  • Accession Number: 01570492
  • Record Type: Research project
  • Source Agency: Federal Highway Administration
  • Contract Numbers: TPF-5(254)
  • Created Date: Jul 22 2015 1:02AM