RES2022-02: Load Rating of Girder Stringer Floorbeam Bridges

Load Rating of Girder Stringer Floorbeam Bridges

There are 31 bridges in Tennessee with superstructure systems consisting of steel girders, floorbeams and stringers. The average age of these bridges is 55 years, and about half are owned by TDOT. Many of these structures carry heavy traffic (up to 74,140 ADT) over significant features such as the Tennessee River and Cumberland River. This bridge type has proven to have good performance history. As part of the December 2020 NBIS Plan of Corrective Action, FHWA has required that TDOT update the load rating of all bridges not designed with LRFD Standards. Of the 31 girder-stringer-floorbeam bridges in Tennessee, 30 require revised calculations. In addition, 6 of these structures were required to be load rated for emergency vehicles as part of the Fast Act. The results of the TDOT load rating calculations for the bridge set have shown low capacity, particularly in the stringers. This is not indicative of the observed performance of these structures. The bridge set has been modelled with AASHTOWare BrR and studied heavily by the TDOT evaluators. In addition, the bridges have been modelled with CSI Bridge software utilizing finite element analysis. Hand calculations have also been made. Weight restriction at many of these bridge locations would be detrimental to the Tennessee economy, safety and to traffic congestion. Since traditional computer modelling and load rating calculation methods have been exhausted, TDOT believes that research in this area would be the best course of action at this time.

• Record URL:
  https://www.tn.gov/content/dam/tn/tdot/long-range-planning/research/final-reports/Final%20Report%20-%20Proj%20No%20RES2022-02%20(6-28-23)_PP.pdf

Language

• English

Project

• Status: Completed
• Funding: $100000
• Contract Numbers:

  RES2022-02

• Sponsor Organizations:

  Tennessee Department of Transportation

  James K. Polk Building
  Fifth and Deaderick Street
  Nashville, TN  United States  37243-0349
• Managing Organizations:

  Tennessee Department of Transportation

  James K. Polk Building
  Fifth and Deaderick Street
  Nashville, TN  United States  37243-0349
• Project Managers:

  Hayworth, Rebecca

• Performing Organizations:

  Tennessee Tech University

  Department of Civil and Environmental Engineering
  1020 Stadium Drive Box.5015
  Cookeville, TN  United States  38505
• Principal Investigators:

  Henderson, Craig

• Start Date: 20220314
• Expected Completion Date: 20230314
• Actual Completion Date: 20230630
• USDOT Program: Transportation, Planning, Research, and Development
• Subprogram: Bridge Safety

Subject/Index Terms

• TRT Terms: Bridges; Live loads; Load factor; Stringers
• Geographic Terms: Tennessee
• Subject Areas: Bridges and other structures; Design; Highways;

Filing Info

• Accession Number: 01889537
• Record Type: Research project
• Source Agency: Tennessee Department of Transportation
• Contract Numbers: RES2022-02
• Files: RIP, STATEDOT
• Created Date: Aug 2 2023 11:24AM