Development of a W-Beam Guardrail System for use on a 2:1 Slope
Karla Lechtenberg, Ronald Faller, Dean Sicking, John Rohde, Jim Holloway, Eric Keller
A W-beam guardrail system was developed and crash tested for use on a 2:1 foreslope. The guardrail design was constructed with 2.66-mm (12-gauge) thick W-beam rails totaling 53.34 m in length and incorporated a half-post spacing section of 17.15 m. The W-beam rail was supported by fifteen W152x13.4 by 1,829-mm long steel posts, spaced 1,905-mm on center, and nineteen W152x13.4 by 2,134-mm long steel posts, spaced 952.5-mm on center. Routed, 150x200x360 wood spacer blockouts were used to block the rail away from each post. The research study included bogie testing on steel posts placed in sloped fill and one full-scale vehicle crash test, using a 3/4-ton pickup truck. The test, impacting at a speed of 100.7 km/hr and an angle of 28.5 degrees, was conducted and reported in accordance with the requirements specified in NCHRP Report No. 350, Recommended Procedures for the Safety Performance Evaluation of Highway Features. The safety performance of the W-beam barrier system was determined to be acceptable according to Test Level 3 (TL-3) of the NCHRP Report No. 350 criteria.
Highway Safety, Guardrail, Roadside Appurtenances, Longitudinal Barrier, Roadside Slopes, Crash Test, Compliance Test