Field and Analytical Study for Deteriorating Precast Double-Tee Girder Bridges

This project discusses the performance of deteriorating double-tee (DT) girder bridges that have been in service for many years. This included field testing of two single-span DT girder bridges in South Dakota for live load distribution factors (LLDFs) and dynamic load allowance (IM). The LLDFs and IM were determined using strain data measured during the tests. When calculating LLDFs, nearly all the measured LLDFs were below the American Association of State Highway Transportation Officials (AASHTO) values. While analyzing the data, it was found that the stems on the same girder did not always have similar strain quantities. Hence, newly proposed stem and joint approaches to calculate the LLDFs were investigated and compared with the conventional girder approach. These results were also compared with those determined according to AASHTO Standard and Load and Resistance Factor Design (LRFD) specifications. It was found that both the AASHTO LRFD and Standard specifications were conservative when estimating IM, compared with the test results for both bridges. Analytical models for both bridges were then created in CSi Bridge to perform parametric studies with variance in DT bridge design parameters. It was concluded that the AASHTO LRFD values are typically conservative for the studied parametric bridges.

  • Record URL:
  • Record URL:
  • Supplemental Notes:
    • This document was sponsored by the U.S. Department of Transportation, University Transportation Centers Program.
  • Corporate Authors:

    South Dakota State University, Brookings

    Department of Civil and Environmental Engineering
    Brookings, SD  United States  57007

    Mountain-Plains Consortium

    North Dakota State University
    Fargo, ND  United States  58108

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • Authors:
    • Seo, Junwon
    • Kidd, Brian
    • Wehbe, Nadim
  • Publication Date: 2021-1


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Figures; Photos; References; Tables;
  • Pagination: 76p

Subject/Index Terms

Filing Info

  • Accession Number: 01766485
  • Record Type: Publication
  • Report/Paper Numbers: MPC 21-426
  • Contract Numbers: MPC-565
  • Created Date: Mar 8 2021 11:42AM