Experimental Validation of the AASHTO Natural Wind Fatigue Design Specifications for Cantilevered Sign Support Structure Anchor Bolts
Publication: Practice Periodical on Structural Design and Construction
Volume 20, Issue 1
Abstract
A cantilevered sign support structure failed, which was attributed to fatigue fracture of the anchor bolts. The failed structure was designed before the publication of the AASHTO fatigue provisions. The structure was replaced with a similar arrangement but designed using the AASHTO fatigue provisions. It was equipped with a double-nut-moment joint to concrete foundation using a 31.75-mm (1.25-in.) thick, 889-mm (35-in.) diameter base plate and eight galvanized 38.1-mm (1.5-in.) diameter bent anchor bolts. Significant clearance discrepancies between the base plate and the foundation for each of the anchor bolts existed because of topographical limitations. Experimental evaluation on the fatigue behavior attributable to natural wind was conducted on the anchor bolt attachments for validation of the AASHTO fatigue provisions. The results of the study indicated an irregular distribution of stress ranges between anchor bolts, with a portion having stress ranges greater than the values calculated using the AASHTO standards as well as the constant-amplitude fatigue limit of the anchor bolt connection detail.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The work described in this document originated from research sponsored by the Alabama DOT (ALDOT) Project #930-683 titled “Design of Overhead Sign Structures for Fatigue Loads.” It is important to acknowledge other participants of the project including Fouad H. Fouad, as well as the hard work and dedication of the ALDOT Maintenance Bureau.
References
AASHTO. (2008). “Standard specification for steel anchor bolts.” AASHTO M314-90, Washington, DC.
AASHTO. (2013). Standard specifications for structural supports for highway signs, luminaires and traffic signals, 6th Ed., Washington, DC.
ASTM. (2013). “Standard specification for high-strength low-alloy columbium vanadium structural steel.” A572/A572M, West Conshohocken, PA.
Collins, T. J., and Garlich, M. J. (1997). “Sign structures under watch.” 〈http://www.roadsbridges.com/sign-structures-under-watch〉 (Oct. 14, 2013).
Davenport, A. G. (1961). “The spectrum of horizontal gustiness near the ground in high winds.” Q. J. R. Meteorol. Soc., 87(372), 194–211.
Dexter, R. J., and Ricker, M. J. (2002). “Fatigue-resistant design of cantilevered signal, signs, and light supports.” NCHRP Rep. 469, Transportation Research Board (TRB), Washington, DC.
Federal Highway Administration (FHWA). (2005). “Guidelines for the installation, inspection, maintenance and repair of structural supports for highway signs, luminaires, and traffic signals.” Publication No. FHWA-NHI-05-036, Washington, DC.
Foley, C. M., et al. (2008). “Fatigue risks in the connections of sign support structures: Phase I.” WHRP 08-05, Wisconsin DOT, Madison, WI.
Harris, C. M. (1996). Shock and vibration handbook, 4th Ed., McGraw Hill, New York.
Hosch, I., and Fouad, F. (2009). “Fatigue design of sign support structures for loading caused by natural wind loads.” Transportation Research Record 2131, Transportation Research Board (TRB), Washington, DC, 15–22.
Kacin, J., Rizzo, P., and Tajari, M. (2010). “Fatigue analysis of overhead sign support structures.” Eng. Struct., 32(6), 1659–1670.
Kaczinski, M. R., Dexter, R. J., and Van Dien, J. P. (1998). “Fatigue resistant design of cantilevered sign, signal and light supports.” NCHRP Rep. 412, Transportation Research Board (TRB), Washington, DC.
Till, R. (1992). “Cantilever sign supports.” Materials and Technology Engineering and Science (Mates) 62, Michigan DOT, Lansing, MI.
Information & Authors
Information
Published In
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Jun 19, 2013
Accepted: Nov 25, 2013
Published online: Nov 27, 2013
Published in print: Feb 1, 2015
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.