EVALUATION OF TIMBER WEAK-POST GUARDRAIL SYSTEMS

SIX FULL-SCALE VEHICLE CRASH TESTS WERE CONDUCTED ON GUARDRAIL SYSTEMS TO EVALUATE THE EFFECTIVENESS OF SUBSTITUTING TIMBER POSTS FOR THE STANDARD 315.7 STEEL POSTS SPECIFIED IN A CURRENT GUARDRAIL STANDARD. RESULTS OF THE TESTS INDICATE THAT TIMBER IS A SUITABLE POST MATERIAL FOR THE "WEAK-POST" CONCEPT. ALTHOUGH THERE WAS SOME DIFFICULTY IN DETERMINING THE PROPER RAIL ATTACHMENT TO THE POST, SOLUTIONS TO THE PROBLEM ARE SUGGESTED IN THIS REPORT. THE TIMBER POST DESIGN CALLS FOR A 12-GAGE FLEXURAL BEAM MOUNTED ON 6- BY 7-IN. OR 5 1/2-IN. DIAMETER PINE POSTS SPACED AT 12.5-FT CENTERS. A 1/4-IN. DIAMETER STEEL BOLT AND A PIPE INSERT PROVIDE PROPER ATTACHMENT OF RAIL TO POST. THE SIXTH TEST OF THE SERIES PROVIDED AN EVALUATION OF THE EFFECTIVENESS OF A CONTINUOUS INSTALLATION COMPOSED OF THE NEW TIMBER WEAK-POST SYSTEM AND THE DEPARTMENT'S STRONG-POST SYSTEM. THE TEST RESULTS INDICATED THAT THE TRANSITION DESIGN BETWEEN THE TWO SYSTEMS WAS SATISFACTORY, BUT DESIGN CHANGES COULD IMPROVE PERFORMANCE. /AUTHOR/

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/hrr/1971/343/343-004.pdf
• Supplemental Notes:
  • Sponsored by Committee on Traffic Safety Barriers and Sign, Signal and Lighting Supports and presented at the 50th Annual Meeting. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Authors:
  • Bronstad, Maurice E
  • Burket, Robert B
• Conference:
  • 50th Annual Meeting of the Highway Research Board
  • Location: Washington District of Columbia, United States
  • Date: 1971-1-18 to 1971-1-22
• Publication Date: 1971

Media Info

• Media Type: Print
• Features: Appendices; Figures; References; Tables;
• Pagination: pp 34-56
• Monograph Title: Design of traffic safety barriers
• Serial:
  • Highway Research Record
  • Issue Number: 343
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Continuous structures; Crash tests; Crashes; Design; Guardrails; Installation; Posts; Steel; Testing; Timber
• Subject Areas: Design; Highways; Maintenance and Preservation; Research;

Filing Info

• Accession Number: 00203548
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Jul 25 1971 12:00AM