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FIGURE 13.38 Effect of soffit plate and fairing for suppressing vortex-excited vibration of open girder [33].

to prevent the flow from rolling on the upper surface of the deck. (e) Deflector has a similar role as the corner vanes for the square-shaped tower introduced in the previous section. The deflector has the role of making the fluid at the leading corner run along the girder shape. (f) Blunt fairing was developed as the fairing for a cable-stayed bridge made of prestressed concrete. At the present time, the blunt fairing is also used in a steel bridge. The concept for the blunt fairing is as follows [34]. The required conditions for a concrete bridge is to eliminate a sharp edge corner, because it is difficult to make the sharp edge corner and the tip of the sharp edge corner is easy to break. After studying aeroelastic performance of various blunt fairings, the upper and lower slopes of the blunt fairing is decided in the shape as shown in Figure 13.39. Figure 13.40 shows the results during the process to decide angle of the lower slope. The lower angle as shown in the figure was changed from 20° to 50° in every 5°. Referring to the figure, the aeroelastic response is remarkably influenced by the lower angles of the blunt fairing. After comparison

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