Reliability-Based Geotechnical Resistance Factors for Axially-Loaded Micropiles

Micropile foundations consist of small-diameter (typically less than 12 inches) drilled and grouted non-displacement, reinforced elements. Such foundations can be constructed in situations of low-headroom, restricted-access, obstructions, and vibration-sensitive sites. However, current micropile foundation design does not incorporate rational reliability-based geotechnical resistance factors, and many state departments of transportation do not have sufficient data or resources to do such calibrations. There was a need to identify the parameters that influence the resistance factors for micropile foundations and develop reliability-based geotechnical resistance factors and specifications that can be used for various design and construction methods. These factors and accompanying specifications should provide an increased level of confidence in the design and help highway agencies in making decisions regarding the use of micropile foundations. The objective of this research was to develop reliability-based geotechnical resistance factors for axially-loaded micropiles and related specifications.


  • English


  • Status: Completed
  • Funding: $249998
  • Contract Numbers:

    Project 04-40

  • Sponsor Organizations:

    National Cooperative Highway Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC  United States  20001

    American Association of State Highway and Transportation Officials (AASHTO)

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

    Federal Highway Administration

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

    Hanna, Amir

  • Performing Organizations:

    University of Missouri, Columbia

    Columbia, MO  United States  65211
  • Principal Investigators:

    Loehr, J

  • Start Date: 20170901
  • Expected Completion Date: 20200430
  • Actual Completion Date: 20200430
  • Source Data: RiP Project 40799

Subject/Index Terms

Filing Info

  • Accession Number: 01598918
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 04-40
  • Files: TRB, RIP
  • Created Date: May 9 2016 11:00AM