engleski

Actual Wind Load and the Comparison of the Results With the Wind Tunnel Tests Upon the Dubrovnik Bridge

The paper presents the computation results for the Dubrovnik steel cable-stayed bridge with a total span of 474 m by using two different sources of wind action. The first set of data was obtained by direct measurements of the wind direction and velocity, second values, acting on the structure at the end of its construction and the second set of data was based on the simulated wind action in the tunnel carried out by prof. G. Sedlacek (Germany). The Bora wind in Croatia is known as a catabatic, very cold and locally changeable wind blowing from the direction of the towards the Adriatic coastline, with the maximum measured wind gusts over 70 m/s. The recently completed measurements of the second values of wind gusts at three points, at different elevations (10, 52 and 140 m) at the pile of the Dubrovnik bridge, and the fourth measurement point, at the other end of the bridge, have made it possible to present the actual action of this highly catabatic wind (it was the first time to measure the wind profile considering the elevations). The results obtained by this computation were compared with the results obtained by computations based on the values of the simulated wind action in the tunnel whit the assumed wind direction and velocity. The paper proves that for the winds of the Bora type the tunnel simulations (the wind tunnel tests) are not suitable so that measurements at actual locations are required. The investigations were performed according to the EUROCODE recommendations and they represent the basis for the development of the Croatian codes in the field of the dynamic wind action upon the structure.

wind load; wind tunnel

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