Development of New AASHTO LRFD Tunnel Design Specifications

There is limited experience in the state departments of transportation (DOTs) with new tunnel design. Most agencies rely on consultants who specialize in tunnel work for design and construction assistance. In addition, The Federal Highway Administration (FHWA) has established a goal to have federally funded projects for "structures other than bridges," like tunnels design by load rating factor design (LRFD), by October 1, 2010. The objective of this proposal is to develop specifications, commentary, and guidelines for tunnel design. The proposal focuses on design standards for structural design, geotechnical design, ventilation, fire control and suppression, and public signing. Very little design guidance is provided in the AASHTO LRFD Bridge Design Specifications for Tunnels in Section 12, Buried Structures and Tunnel Liners. The material on tunnels will be removed and included in a new section. Additional specifications and guidance must be developed and included in the new section. It is expected that the contractor will use existing guidelines, especially those developed by FHWA and the National Fire Prevention Association, to prepare the specifications, commentary, and guidelines. This strategic research need is identified in the AASHTO Highway Subcommittee on Bridges and Structures' 2005 Strategic Plan for Bridge Engineering, as part of Grand Challenge 4, Advancing the AASHTO Specifications, Grand Challenge 1, Extending Service Life, and Grand Challenge 2, Optimizing Structural Systems. The objective of the proposed research is to improve the design of highway tunnels by developing specifications and guidelines for road tunnel design. The research will produce a draft design specification and commentary in the format of the AASHTO LRFD Bridge Design Specifications. There is an urgent need to develop and improve the current methods of tunnel design, operation, and rehabilitation. These improved methodologies will increase the reliability and effectiveness of highway tunnel operations, leading to improved tunnel safety and more effective operation and management of tunnels in state and local tunnel inventories. The results of this research will provide guidelines suitable for implementation by state DOTs. It is anticipated that the research results will be presented to the AASHTO Subcommittee on Bridges and Structures, T-20 Technical Committee on Tunnels, for consideration and adoption into the LRFD Specifications. The technical committee will work with FHWA and NHI to develop training as needed based on the new specifications.


  • English


  • Status: Proposed
  • Contract Numbers:

    Project 12-89

  • Sponsor Organizations:

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  USA  20590

    American Association of State Highway & Transportation Officials

    444 North Capitol Street, NW, Suite 225
    Washington, DC    20001

    National Cooperative Highway Research Program

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

    Dekelbab, Waseem

  • Start Date: 20100615
  • Source Data: RiP Project 26493

Subject/Index Terms

Filing Info

  • Accession Number: 01463915
  • Record Type: Research project
  • Source Agency: National Cooperative Highway Research Program
  • Contract Numbers: Project 12-89
  • Files: TRB, RiP, USDOT
  • Created Date: Jan 3 2013 2:32PM