Four vehicular crash tests conducted on metal beam guardrail envelopes called "bullnose barriers" are reported. Large size passenger cars weighing about 4,900 lbs (2,220 kg) impacted the barriers at speeds of 41 to 64 mph (18 to 29 m/sec). In three tests the vehicle impacted the nose of the barrier head-on, and in the last test it struck the nose in a 10 deg/18 in. off-center attitude. The barriers consisted of two flared sides of W-section guardrail joined at one end by a curved section with about a 5 foot (1.5 m) radius. The barriers were supported by wood posts and anchored with cables at the front and back of each flared side of the barrier. Some designs also included the following features: breakaway cable anchors, different post sizes, torsional post reinforcement, concrete footings, and a secondary cable restraint system. A bullnose design capable of stopping and containing a 60 mph (27 m/sec) head-on impact at low deceleration with no intrusion of barrrier or vehicle components into the passenger compartment and little barrier debris was developed. However, a high speed vehicle impacting off-center at an angle into a similar barrier rode down the front of the barrier without being stopped or contained. Recommendations for further testing and suggested design changes are included to improve the capability of the barrier for off-center angular impacts.

  • Supplemental Notes:
    • This study was conducted in cooperation with DOT, Federal Highway Administration.
  • Corporate Authors:

    California Department of Transportation

    Transportation Laboratory
    5900 Folsom Boulevard
    Sacramento, CA  United States  95819
  • Authors:
    • Parks, D M
    • Stoughton, R L
    • Stoker, J R
    • Nordlin, E F
  • Publication Date: 1976-6

Media Info

  • Pagination: 94 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00158061
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWACADOTTL63957635 Final Rpt., FCP 41G1062
  • Contract Numbers: D-4-37 HP&R
  • Created Date: Oct 13 1977 12:00AM