Since a statistical approach to the wind loading problem was proposed in the early 1960's, there have been a number of gust response approaches developed. However some simplification or approximation employed in those approaches seems to lead to inaccurate predicted results in some circumstances. An improvement of the gust response approach has been attempted in this work. Firstly a flexible mathematical model of natural turbulence characteristics has been suggested as a result of reviewing recent works. Formulae suggested include various parameters which allow the height dependence of power spectral density and co-coherence of the longitudinal turbulence component to be taken into account. For mathematical convenience the height dependence of wind characteristics has been expressed in terms of a power law profile. These height dependent expressions with appropriate parameters have been incorporated with a method for gust response prediction. Secondly the dynamic along-wind force coefficient concept has been employed to improve the conventional stochastic prediction theory for gust response. The coefficient has been evaluated experimentally by using a two-dimensional single degree of freedom system model in a partial boundary layer wind tunnel. Experimental results for the static drag coefficient showed some relevance to previous works. Experimental results for the dynamic along-wind force coefficient have been reduced into an empirical form, with the section aspect ratio and the reduced wind speed as variables, in terms of its ratio to the static drag coefficient. A computer program for the gust response prediction has been developed and convenient chart diagrams have been presented for practical applications. Effects of the variation of parameters used in the wind characteristics' model have been examined numerically and the significant role of the dynamic along-wind force coefficient in the gust response prediction discussed.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:653193 |
| Date | January 1979 |
| Creators | Kanda, Jun |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/15138 |
Page generated in 0.0019 seconds