In and around highway construction zones, delineation devices as well as barriers are used to control and restrict the flow of traffic. The need for positive, containing barriers was recognised by the Federal Highway Administration (FHWA). The FHWA further recognised that many temporary barrier devices were being used without documented performance. Accordingly, four temporary barriers were selected for crash test evaluation: (1) 25x25 cm(10"x10") timber barrier; (2) W-beam/barrel barrier; (3) Type X curb; (4) Stacked timber barrier. These barriers were subjected to controlled impacts with full size 2040-kg (4500-lb) cars impacting at angles from 7 to 15 degrees at speeds from 56 km/h (35 mph) to 90 km/h (56 mph). Results indicate the first and third barrier designs had minimal redirection/containment capacity, and performance was judged to be poor. The W-beam/barrel concept performed well during a 72 km/h (45 mph), 15-deg angle impact, but performance was unsatisfactory for 55 mph (88 km/h), 15-deg angle. The stacked timber barrier provided smooth redirection for both 35 mph (56 km/h) and 50 mph (80 km/h) impacts. (FHWA)
Samenvatting