Project 2a: Reliability-based Evaluation of Bridge Components for Consistent Safety Margins - MS&T

The objective of this project is to calibrate load and resistance factors in LRFD Design Guidelines, (LRFD hereafter) under Service Limit State. The project will be carried out with three main tasks. Task 1 of the project will include identification of service load in Missouri, identification of Service Limit State of existing bridges designed with Load Factor Design, (LFD hereafter), and associated cost to maintain the bridge performance. Extensive data for the past twenty to thirty years will be collected including daily traffic, bridge maintenance records, and relevant costs. The collected data will be organized in efficient and extensible database which can be used in Task 2 and 3 as well as for a future study. Service Limit State will be determined based on the performance of bridges in the past years. In the Task 2 of the project, reliability of bridge components designed with LRFD will be analytically evaluated. The focus of the reliability analysis will be on Service Limit State. Load models and Service Limit States from Task 1 will be used in reliability analysis. Load factors will be calibrated with two main objectives: 1) the bridge components should have consistent safety margin, and 2) the bridge components designed with LRFD should be compatible with components designed with LFD which have performed well for the past years. In the Task 3 of the project, based on the results from Task 2, revised load factors for LRFD Guidelines will be suggested. In addition, necessary changes in the current Missouri Department of Transportation (MoDOT) Standard Plans for Highway Construction will be identified and made in consultation with MoDOT bridge engineers. The revised Standard Plans will guide private consultants and MoDOT engineers for new bridge designs that are consistent with the LRFD Bridge Design Manual. The calibrated load and resistance factors are expected to save overall cost in bridge construction and maintenance. The outcome of this project will provide sound background on load factors for Service Limit State, which has been determined primarily based on engineering judgment.


  • English


  • Status: Completed
  • Contract Numbers:



  • Sponsor Organizations:

    Center for Infrastructure Engineering Studies

    Missouri University of Science and Technology
    Rolla, MO  United States  65409

    Missouri Department of Transportation

    1617 Missouri Boulevard
    P.O. Box 270
    Jefferson City, MO  United States  65102
  • Principal Investigators:

    Kwon, Oh-Sung

  • Start Date: 20080901
  • Expected Completion Date: 0
  • Actual Completion Date: 20100831
  • Source Data: RiP Project 18897

Subject/Index Terms

Filing Info

  • Accession Number: 01462500
  • Record Type: Research project
  • Source Agency: Center for Infrastructure Engineering Studies
  • Contract Numbers: DTRT06-G-0014, 00022973
  • Files: UTC, RiP, STATEDOT
  • Created Date: Jan 3 2013 2:04PM