More than a half century ago, the dramatic collapse of the Tacoma Narrows Bridge sparked a major investigation into the effects of wind on suspension bridges. To coordinate the many activities that were to be undertaken, the Advisory Board on the Investigation of Suspension Bridges was formed. The Board was broadly representative of engineers responsible for specific suspension bridges, research engineers having competence in aerodynamics and suspension bridge theory, and representatives of industry with demonstrated ability and leadership in the fabrication and erection of suspension bridges.

The Bureau of Public Roads (later the Federal Highway Administration), embarked upon a broad research program which involved coordinating national and international wind investigations, sponsoring contract research, conducting laboratory and field studies in-house, and providing technical guidance through committees, panels, or research councils.

The Bureau made a careful survey of existing wind tunnel facilities in the United States to determine if one might be adapted for the purpose of studying the effects of wind forces on suspension bridges. The results of the study determined that it would be more cost effective and expeditious to build its own specialized facility. During the 1950's, the Aerodynamics Laboratory and wind tunnel were designed, constructed, and placed into service at the Turner-Fairbank Highway Research Center in McLean, Virginia.

The facilities, which have evolved from this research program, are unique in the Nation. The Aerodynamics Laboratory is the only wind tunnel specifically designed for and dedicated to ensuring the aerodynamic stability of transportation structures, especially long-span bridges. The wind tunnel, with its relatively large cross section produces laminar flow and is very stable at low velocities. Its size and velocity range enable both static and dynamic investigations of large-scale section models of structures and structural components. The significance of structural details can be evaluated as well. A computer-driven turbulence simulation system is available to introduce properly scaled gusting into the air flow during testing. This system was the first of its kind in the world. To measure wind forces on sectional models, a high-frequency, dual force-balance system is available. Although other wind tunnels use high-frequency balances, ours is unique in that it is actually two matched balances in one system and can be used to directly measure unbalanced loads on the structural model.

To complement the research and development activities associated with wind tunnel experiments, the activities of the laboratory were expanded. Over the years, laboratory activity has grown to include more and more full-scale studies, with many bridges across the United States being instrumented and analyzed. In addition, in recent years, efforts have been under way to develop numerical and computational modeling of fluid and structural behavior interaction, in particular, as applied to long-span bridges.

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