WIND EFFECTS ON THE EXISTING AND PROPOSED TACOMA NARROWS BRIDGES

In this paper, wind engineering studies of the proposed Tacoma Narrows Bridge are described as well as studies of modifications to the existing bridge. The new bridge, running parallel to the existing bridge, will be 61 m from center line to center line when complete. The proposed bridge will run parallel to and close to the existing bridge. Sectional models at a 1:50 scale and full aeroelastic models at a 1:211 scale of both bridges were built and tested to evaluate aerodynamic stability and wind loading. Field vibration measurements were also taken on the existing bridge to confirm its dynamic characteristics. Of particular interest, because of the 2 bridges' close proximity, was the potential for aerodynamic interactions between them. The results of the field tests and wind tunnel studies are provided.