強風時における乱れのスペクトルについて

Abstract

Spectra of gustiness in high wind are very important knowledge for the design ofbuildings or other constructions, but we don't have enough observational data for studynow. In this paper, results ofa study of spectra of gustiness observed on Tokyo Towerin high wind are shown. Observation heights are 20, 66, 106 and 253 m and the recordsof 5 cases (10 mm. In length for each), whose averaged wind speed at 253 in is about33 in/sec, are used for spectral analysis in Tukey method. Results show with one exceptionthat power spectral density decreases in proportion to the -3/4th power of frequencywithout any significant peak at every height. But one case (Run No. 2) shows signifi-cant power peaks at heigher levels. This situation may have some relations with coldfront passage. But at lower levels, the spectrum for each run resembles each otherthroughout cases.