Evaluation of Load Rating by Load and Resistance Factor Rating

Guide Manual for Condition Evaluation and Load and Resistance Factor Rating (LRFR) of Highway Bridges, 1st Edition and 2005 Interim" </span>was developed under NCHRP Project 12-46. Before the Guide Manual was endorsed by the AASHTO Highway Subcommittee on Bridges and Structures (HSCOBS) to become a full manual, some additional research was requested to explain differences between the new manual and the established load factor rating (LFR) requirements. NCHRP 20-07/Task 122 provided explicit comparisons between ratings produced by the LRFR methods of the Guide Manual and the load factor ratings from the latest edition of the <em>AASHTO Manual for Condition Evaluation of Bridges</em>.  Nevertheless, because the Task 122 scope was limited to flexural ratings and the number of structures rated was small, HSCOBS wanted more bridges rated and LRFR/LFR comparisons made for moment and shear induced by a variety of loads. The choice of load rating method may affect the transportation of goods and services over the nation's highways by restricting routes that were previously unrestricted. Additional comparisons of LRFR and LFR ratings are needed to (1) develop refinements to the load rating process that maintain an acceptable level of bridge reliability without unnecessary restrictions on commerce and (2) explain changes in truck weight restrictions to the public. The objectives of this project are to recommend refinements to the LRFR methods in the <em>AASHTO </em><span><em>Manual for Bridge Evaluation</em> and to explain changes in truck weight restrictions. A comprehensive database of rating comparisons shall be established to identify differences in ratings and to develop the proposed refinements. </span></font></div>


  • English


  • Status: Completed
  • Contract Numbers:

    Project 12-78

  • Sponsor Organizations:

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    American Association of State Highway and Transportation Officials (AASHTO)

    444 North Capitol Street, NW
    Washington, DC  United States  20001

    National Cooperative Highway Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC  United States  20001
  • Project Managers:

    Dekelbab, Waseem

  • Performing Organizations:

    Michael Baker Jr., Incorporated

    100 Airside Drive
    Moon Township, PA  United States  15108-
  • Principal Investigators:

    Mlynarski, Mark

  • Start Date: 20080303
  • Expected Completion Date: 0
  • Actual Completion Date: 20110318
  • Source Data: RiP Project 16899

Subject/Index Terms

Filing Info

  • Accession Number: 01464580
  • Record Type: Research project
  • Source Agency: National Cooperative Highway Research Program
  • Contract Numbers: Project 12-78
  • Files: TRB, RiP, USDOT
  • Created Date: Jan 3 2013 2:45PM