This report presents the design and development of an asphalt vegtation control treatment that allows installation of a steel-post W-beam guardrail system with posts installed directly in asphalt.The asphalt vegetation control design was developed using a series of bogie vehicle impact tests that evaluated the guard rail, posts, performance, and various asphalt thicknesses at various offsets from the edge of the asphalt. The force deflection response of the posts installed in the asphalt was compared to the response of the post installed directly and soil. Using these comparisons, a design of the asphalt vegetation control treatment was recommended for full scale, crash testing of the steel-post w-beam guard rail system.
Testing of the steel post w-beam guard rail in asphalt vegetation control treatment was performed according to the safety performance evaluation guidelines included in the second addition of the American Association of state highway and transportation officials (AASHTO) manual for assessing safety hardware (MASH) (1). The tests were performed in accordance with MASH test level three (TL-3), which involves performing MASH test 3–10 and MASH test 3–11.
This report provides details on the steel – post W-beam guard rail in asphalt vegetation control treatment, the crash test and results, and the performance assessment of the guard rail for MASH TL – 3 evaluation criteria for longitudinal barriers. The steel post w-beam guardrail in asphalt vegetation control treatment met the performance criteria for an MASH TL-3 for longitudinal barriers.
