円筒形塔状構造物の強風による振動

Abstract

A lateral vibration of a cylindrical tower structure induced by strong wind is presen-ted. We observed the amplitudes of displacement at the top of the Kyoto Tower, whenthe typhoon No.24 in 1965 passed Kansai district. The typhoon was attended with maximumpeak gust 51 n/sec at the top, and we discussed some problems below the mean windspeed 35 in/sec. Before the relationship between the amplitudes and the wind speed wasmade clear, the time duration of fluctuating wind velocity was dealt to fit the characteris-tics of the structure. In this range of wind speed the maximum amplitude arised at28m/sec. Though the oscillatory movement of the tower was classified as "self-excited", its states are generally like "beat ". These phenomena are thought that the movementsof the tower induce the vortices in increasing its amplitude and contrariwise the vorticescontroll the movement in decreasing it.