Wind tunnel experimental investigation on tapered cylinders for highway support structures

Highway support structures are an important component of the United States highway system. Over the years, wind-induced vibration of these structures has been observed throughout the country under a variety of conditions. A number of recent major failures, some resulting in deaths has sparked interest in the wind loads on and fatigue design of highway support structures. Design is currently guided by the AASHTO specifications. Although the design codes received major revision in 1985, there is concern that they still do not adequately address the effects of wind on these structures. To gain better understanding of the problem and to develop recommendations for code revisions, several projects have been initiated at the State and Federal levels. A portion of this project involves wind tunnel experiments to establish the effects of wind on tapered cylinders. The experimental program and early results are the subject of this paper.