AASHTO 2001 DESIGN OF OVERHEAD CANTILEVERED SIGN SUPPORTS

The American Association of State Highway and Transportation Officials (AASHTO) "Standard Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals" was revised in its entirety through a major research project conducted under the auspices of the National Cooperative Highway Research Program (NCHRP) Project 17-10. The new document was approved in 1999 by all state departments of transportation for adoption by AASHTO and was published in 2001. The revisions include updated provisions and criteria for extreme wind loads and new provisions and criteria on fatigue design. These provisions differ considerably from those in previous editions of the specifications. The impact of the new wind load and fatigue provisions on the design of cantilevered overhead sign supports from the standpoint of safety and economy had not been studied and was the main goal of this project. wind load and fatigue calculations and design of a cantilevered overhead sign support in Alabama were performed using the design criteria in both the 2001 AASHTO specifications and the 1994 edition of the specifications, using SABRE, a structural analysis package for overhead sign support structures. The results were compared and the impact of the 2001 specifications on design of cantilevered overhead sign support structures in Alabama was illustrated.