Development and MASH Full-Scale Crash Testing of a High-Mounting-Height Temporary Single Sign Support with Aluminum Sign (9-1002-12-5)

Work zone traffic control devices such as temporary single sign supports are a primary means to communicate information to motorists in work zone areas. The Federal Highway Administration and the Manual on Uniform Traffic Control Devices require work zone traffic control devices to be crashworthy. That is, they should not pose a safety hazard to motorists and/or work zone personnel if impacted by errant vehicles. The objective of this research was to develop a nonproprietary, lightweight, crashworthy, work-zone single sign support for use with an aluminum sign substrate mounted at a height of 7 ft. The device is intended to meet the evaluation criteria in MASH. Texas A&M Transportation Institute (TTI) researchers decided to utilize perforated steel tubing for the frame of the new temporary single sign support system to accommodate requests to help make the system lightweight, durable, easy to assemble, and adjustable. Design concepts were developed and evaluated through engineering analysis, developmental full-scale crash tests, and finite element computer simulations. Results were reviewed with the project monitoring committee and a system was selected by TxDOT for evaluation through full scale crash testing. MASH Test 3-72 with the 2270P pickup truck was performed to evaluate the behavior of the sign support oriented at both 90 degrees and 0 degrees. The sign support system oriented at 0 degrees passed all the MASH evaluation criteria. Secondary contact between the pickup truck and the aluminum sign panel of the sign support system oriented at 90 degrees caused a cut in the roof that constituted occupant compartment intrusion. Consequently, the sign support system did not pass MASH occupant risk criteria. The report recommendations possible design modifications to mitigate this behavior and improve impact performance for the pickup truck.