Refined Design Methods for Lean-on Bracing

Details

• Creators:
  Bjelland, Aiden ; Gasser, Claire ; Fish, David ; Helwig, Todd ; Yarnold, Matthew ; Park, Sunghyun ; Patel, Shrey ; Hurlebaus, Stefan ; Hebdon, Matthew ; Engelhardt, Michael ; Williamson, Eric
• Corporate Creators:
  University of Texas at Austin. Center for Transportation Research ; Texas A&M University. Texas Transportation Institute
• Corporate Contributors:
  Texas Department of Transportation. Research and Technology Implementation Office ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  Bracing Bridge Construction Bridge Performance Cross-frame Behavior Finite Element Method Guidelines Lean-on Bracing Stability Bracing Steel Bridges Structural Stability (Mechanics) Weight

  More +
• Publication/ Report Number:
  FHWA/TX-24/0-7093-1
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Texas
• Edition:
  September 1, 2020 - January 12, 2026
• Corporate Publisher:
  University of Texas at Austin. Center for Transportation Research
• Abstract:
  Cross frames are structural elements that are critical for the stability of steel bridges during erection and construction and also play an important role for completed bridges. Historically, the brace locations have been regions of fatigue concerns. In addition, the braces require significant handling and processing during fabrication and represent one of the most expensive components per unit weight on the bridge. Therefore, there are major benefits in terms of economics and structural performance to minimize the number of cross frames. Lean-on bracing concepts that replace full cross frames in certain bracing lines with top and bottom struts that allow a single cross frame to brace several girders is a method of minimizing the number of cross frames on a bridge. Lean-on concepts for bridge applications were developed in the early 2000's on TxDOT study 0-1772. While the previous study developed design guidelines, recent applications of lean-on bracing on TxDOT bridge designs demonstrated the need for improved efficiency and clarity. The research conducted on this investigation include field monitoring, parametric finite element analyses, and the development of design equations based upon extensive parametric finite element analyses. Results of the research are presented and discussed and refined design methods were developed that provide guidance on effective use of lean-on bracing. The recommendations are demonstrated through design examples.
• Format:
  PDF
• Funding:
  0-7093
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:3b1980b4a15b32b524a2c920bc66509789b4ebb93f400e998599e62d8b60033565d7ea0337cc6251347d6358a93ede928f0f696dc4162153752deaa2e5491f3c
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/93050/dot_93050_DS1.pdf
• File Type:
  [PDF - 14.74 MB ]