STATIC AND DYNAMIC BEHAVIOR OF 'TRI-CHORD TRUSS' OVERHEAD SIGN SUPPORT STRUCTURES

This report presents the results of a three part research effort on the experimental, static, and dynamic behavior of tri-chord overhead sign support structures. The experimental effort was primarily concerned with the degree of fixity of the column to truss connection required for analytic modeling. Repeated load tests of the chord splice are also included to provide information regarding fatigue strength. Analysis of dynamic response to extreme wind loads indicate that the AASHO Specifications are adequate. It is also shown that Stockbridge dampers are effective in reducing vibrations due to wind excitation. Finally, a computerized and highly reliable approximate method of analysis is devised for this type of structure. The method accounts for tapered chord tubes and permits the columns to be either one tube or two tubes trussed together. The U-bolt connections are assumed not to slip and no consideration is given to precambering or buckling instability. Comparison of approximate and 'exact' methods shows close agreement. The computer program is listed in the Appendix.

• Supplemental Notes:
  • Prepared in cooperation with North Carolina Dept. of Transportation and Highway Safety, Raleigh.
• Corporate Authors:

  North Carolina State University, Raleigh

  Highway Research Program, P.O. Box 5993
  Raleigh, NC  United States  27607

  North Carolina Department of Transportation

  P.O. Box 25201, 1 South Wilmington Street
  Raleigh, NC  United States  27611

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Mirza, J F
  • TUNG, C C
  • Smith, J C
• Publication Date: 1975-9

Media Info

• Pagination: 321 p.

Subject/Index Terms

• TRT Terms: Accelerated tests; Aerodynamic force; Columns; Computer programs; Dampers; Dynamic loads; Dynamic structural analysis; Fatigue strength; Gusts; Highway traffic control; Highways; Load tests; Overhead traffic signs; Repeated loads; Splicing; Statics; Structural supports; Trusses; Vibration; Wind; Wind pressure
• Uncontrolled Terms: Dynamic response; Gust loads; Static response; Wind load
• Old TRIS Terms: Supports
• Subject Areas: Bridges and other structures; Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00151154
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: ERRSD-110-71-3 Final Rpt., FHWA/RD-77-S0560, FCP 40S1-022
• Files: NTIS, TRIS, USDOT, STATEDOT
• Created Date: Mar 30 1977 12:00AM