Abstract
For investigating how a high-rise building will be displaced in response to the wind pressure fluctuation, the wind velocity above the Kasumigaseki Building was registered by an anemometer of pitot-differential potentiometer type set at the scaffold built up 10m high on the penthouse during Typhoon No.22, 1967, while the long and short components of the vibration of the building were respectively measured by the vibrogaphs set on the 35th, 21st and 12th floor and the plumment of piano wire about 100m long suspended from the roof to the 13th floor in the staircase under construction. Then, from the power spectral density of the wind fluctuation, the maximum displacement of the building was theoretically calculated as one-mass system and multi-mass system and found in good agreement with the measured value. In short, the long components of the vibrations of a tall building are random and caused by gusts of wind, with the fundamental mode, while its short components are negligibly small as compared with the long ones, though they are rather regular of natural frequencies with the fundamental mode.
