GUARDRAIL AND GUARDRAIL TERMINALS INSTALLED OVER CURBS - PHASE II

A barrier system was developed for installation where W-beam is placed over curbs. The guardrail design was constructed with two 2.66-mm (12-gauge) thick nested W-beam rails totaling 26.67 m in length. The nested W-beam rail was supported by fifteen W152 x 13.4 steel posts, each measuring 1,830 mm long. Post spacings were 1.905 mm on center. The concrete curb was a type "G" curb that measured 203 mm wide x 102 mm high x 19.05 m long. The research study included full-scale vehicle crash testing, using a 3/4-ton pickup truck. The full-scale test, impacting at a speed of 100.3 km/hr and an angle of 28.6 deg, 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 guardrail/curb combination barrier system was determined to be acceptable according to the Test Level 3 (TL-3) evaluation criteria specified in NCHRP Report No. 350.