Testing and Evaluation of Wyoming Road Closure Gate (TTI-1997-11)

Road closure gates are used to close certain highways when the driving conditions become too hazardous under severe winter weather conditions. The Wyoming Department of Transportation (WYDOT) developed a new road closure gate design that had not been crash tested to determine if it would meet nationally recognized safety standards. The WYDOT sponsored a study at the Texas Transportation Institute to crash test and evaluate the new road closure gate design and, as appropriate, to improve the design from the standpoints of safety performance, cost and practicality. The original road closure gate design was crash tested and failed to meet guidelines set forth in NCHRP Report 350 and the 1985 AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals. The design was then modified and crash tested with successful results. The modified road closure gate design consists of: a standard 8.84 m (29 ft) high luminaire support pole structure with a mast arm and light standard; a 4-bolt slip base breakaway base; a telescoping fiberglass/aluminum gate arm with an electric in-line linear actuator lift mechanism; and a gate arm bracket to restrict the lateral movement of the gate arm in the up position. The road closure gate design has been adopted by the Wyoming Department of Transportation and accepted by the Federal Highway Administration for use on the National Highway System.