Instrumentation to Aid in Steel Bridge Fabrication

There are many documented and undocumented cases of steel bridge erection problems. This is especially true for complex structures, such as curved girders and box structures. As an example, in 2001 the Virginia Department of Transportation was faced with a problem at the Magruder Boulevard over I-64 Bridge in Hampton, Virginia. Here an incorrectly fabricated girder was not identified until most of the structure was erected and some components did not fit together. This single incident resulted in millions of dollars in legal expenses, re-fabrication expenses, and delays in construction of the bridge. Because of these types of problems, most states require a steel bridge fabricator to shop assemble some or all parts of a steel bridge. This practice is intended to assure that the structure, primarily the splice plates and cross frames, will fit together at the job site as designed. This shop assembly procedure is labor and time-in¬tensive and adds significant cost to a steel bridge. In addition, quality control data is typically taken by hand with string lines and rulers and recorded manually on paper reports. This process can sometimes contain errors (i.e. wrong number written down or errors in measurements) and does not provide a complete permanent record of a fabricated component. This research will deliver a laser based bridge measurement system that will greatly improve the quality and reduce the cost of complex bridge fabrication. This system will reduce or eliminate the need for shop fit-up and assembly by providing a virtual assembly capability using specialized solid modeling and analysis software specifically targeted at large-scale complex structures. This laser system will be specifically designed for steel bridge fabrication and will accurately and precisely measure all aspects of a bridge component, including splice hole locations, camber, sweep, and end-kick in a nearly full-automated manner. The completed system can be used as a quality control tool to document as-built conditions of girders and as a virtual fit-up tool to eliminate shop assembly. There is no existing laser-based measurement system that can measure very large and very complex girders with the accuracy, as rapidly, and with as little operator intervention as that being proposed. The use of this laser system on just one complex bridge job could result in benefits that exceed the cost of this entire research project. The stakeholder group that can potentially benefit the most from the use of the proposed laser system are the State departments of transportation (DOTs), who could save millions of dollars on the cost of steel bridges and receive greater quality assurance on the end product. Elimination of shop assembly of complex structures could save millions of dollars. The proposed system can identify fabrication errors at the fabrication shop allowing repairs to be made prior to painting and shipment to a job site. Documentation from the proposed system is a permanent record that is certifiable and traceable. This documentation can be used to help reduce construction claims and could serve as evidence in legal disputes in cases where there are problems during bridge erection. Avoiding the legal expenses from one such dispute of this type could more than pay for the cost of this research.

Language

  • English

Project

  • Status: Proposed
  • Funding: $250000
  • Contract Numbers:

    TPF-5(226)

  • Sponsor Organizations:

    New York State Department of Transportation

    50 Wolf Road
    Albany, NY  United States  12232

    Virginia Department of Transportation

    1401 East Broad Street
    Richmond, VA  United States  23219

    Texas Department of Transportation

    125 E. 11th Street
    Austin, TX  United States  78701-2483

    Iowa Department of Transportation

    800 Lincoln Way
    Ames, IA  United States  50010

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Project Managers:

    Kassner, Bernie

  • Start Date: 20111020
  • Expected Completion Date: 20150331
  • Actual Completion Date: 0
  • Source Data: RiP Project 42024

Subject/Index Terms

Filing Info

  • Accession Number: 01560746
  • Record Type: Research project
  • Source Agency: Federal Highway Administration
  • Contract Numbers: TPF-5(226)
  • Files: RiP, USDOT
  • Created Date: Apr 22 2015 1:03AM