A sudden severe storm destroyed a large tent structure connected to some concrete weight cubes, at near coast in Tsuruga City, Fukui Prefecture. High wind accompanied with the gust-front in the storm killed a man and injured nine persons. While the tent structure had an opening faced to sea, it was covered on remained walls with canvas. In this situation, when wind attacked from the open face, the tent would be easily lifted up, even though some weights might fairly resist to the lift caused by wind. This study describes the observation of damage to the tent structure and wind tunnel test results, which was carried out to quantify the wind load when the tent will be blown off in various situations of wall coverings.
An edge-girder deck is often used for cable-stayed bridges because of its structural simplicity and economical advantages. Aerodynamics of edge-girder decks has been studied by many researchers so far and less stability has often been reported. This paper presents a wind-tunnel test study of aerodynamic/aerostatic characteristics of an edge-girder deck (width/height = 12) of a composite cable-stayed bridge. As a result, large amplitude vortex-induced vibration occurred in vertical and torsional directions. It was found that vortices separated from the leading edge play a role to cause vortex-induced vibration. It was also found that onset wind speed and amplitude of vortex-induced vibration can be estimated by formulae in the wind-resistant design manual for road bridges. A three-component-force test showed that drag coefficient of the deck is by 30% larger than that of a similar type deck (plate girder) specified in the bridge design specification in Japan.
This note describes a platinum coating method of a tungsten wire for hot-wire anemometry. The resistance deviation of the coated tungsten wire stayed within ±2% during a half year. Using sensors with the coated tungsten wire, we obtained expected results of turbulent intensities and spectra in the turbulent boundary layer. This platinum coating method makes the tungsten wire sensor stable.