Guidelines for the Load and Resistance Factor Design and Rating of Riveted, Bolted, and Welded Gusset-Plate Connections for Steel Bridges

Gusset plates for main load carrying members and bracing elements in steel bridges are generally intended to transfer the applied forces from member to member through axial and shear loads. However, bridge connections often present analytical and design challenges whereby several members are framing into the same connection hence introducing a complex geometry and state of stress, which often lead to varying assumptions of load path and vastly different design and rating methodologies. These range from simple analysis and design of axially loaded connections to those involving an interaction between flexural, shear, and axial stresses.<span>   Further, many theories are available to determine the assumed configuration of the resisting elements as well as the resistance of each element to withstand yielding, fracture, and buckling of the connected members and plates. Over the years, studies of gusset connections have been limited to building-type bracing systems. Recent work at the University of Utah presented an exhaustive review of national and international gusset plate literature for brace frame gusset plate research (Janice J. Chambers and Christopher J. Ernst, 2005). The review goes back to papers published in the early 1930s and through 2005. However, most of the research was focused on building-type connections with very limited research on bridge-type connections. The only few bridge investigations were limited to seismic behavior of gusset connections. Having the vast majority of research focused on building-type connections and most investigations resulting in differing conclusions, there exists a need for a comprehensive yet focused investigation on bridge-type connections. The methodology must yield validated, consistent methodology that assures public safety without undue burden on bridge owners for design and rating purposes. Recent failures of gusset bridge connections and the current national urgency to properly design and rate gusset truss connections points to the need for further analytical and experimental investigations to verify and/or modify existing procedures, and to provide guidance to the bridge engineers for the proper design and rating of riveted, bolted, and welded gusset connections. The main objectives of this research are: (1) Perform advanced finite element analyses of varying bridge gusset connection types, configurations, loadings, and failure modes to verify or modify existing procedures, or develop new design and rating procedures. (2) Perform large-scale experimental investigations to validate the findings of the finite element analyses. (3) Based on the analytical and experimental investigations, develop recommendations for optimal connection configurations to maximize the resistance of gusset connections and minimize the possibility of unfavorable failure modes.</font> (4) Develop guidelines, specifications, and examples for the load and resistance factor design and rating of gusset connectionsCurrently, the lack of uniformity and best practices in the design and load rating of gusset connections results in confusion, unknown safety hazards, and possibly unnecessary checks. There is a pressing urgency to develop safe guidelines and procedures to help bridge owners design and load rate steel bridge gusset connections. These guidelines must be verified to ensure that connections are not only properly designed and rated but most importantly without imposing unnecessary burdens. The new guidelines are expected to assure safety of new and existing bridges as well as simplify design and rating to avoid unfavorable failure modes. Further, bridge owners are currently in need of these procedures along with numerical examples necessary to properly interpret and implement any new procedures. This research meets the AASHTO Grand Challenge 4 in the area of "Enhanced Specifications for Improved Structural Performance.


  • English


  • Status: Active
  • Contract Numbers:

    Project 12-84

  • 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

  • Performing Organizations:

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  USA  20590
  • Principal Investigators:

    Ocel, Justin

  • Start Date: 20081001
  • Source Data: RiP Project 18036

Subject/Index Terms

Filing Info

  • Accession Number: 01464470
  • Record Type: Research project
  • Source Agency: National Cooperative Highway Research Program
  • Contract Numbers: Project 12-84
  • Files: TRB, RiP, USDOT
  • Created Date: Jan 3 2013 2:43PM