Approximation of Cross Spectra of Fluctuating Pressures on Dome-like Structure’s Surface

• Main Authors: Hsiang-Ling Lin, 林香伶
• Other Authors: Yuan-Lung Lo
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/93520324867296084526

碩士 === 淡江大學 === 土木工程學系碩士班 === 104 === When the demands for leisure activities and a large number of storage spaces are increasing, there are more and more large-span structures being constructed. The unique features of large-span structures are their large span roofs and lighter materials, which make them sensitive to wind loads. Therefore wind effect on large-span roofs have become the most important issue in the whole design procedure. Related researches about large-span structures in the past have been explored by a number of scholars. Reynolds number, turbulence intensity and roof curvature dominate the estimation of the wind loads. However, most conclusions were given in qualitative discussion. This present study adopts several different curvatures for hemispherical dome structures in Lo and Kanda’s experiments. By comparing proposed empirical formulas and the one proposed in the present study, cross spectrum of any two neighboring fluctuating pressures along the roof meridian have been well approximated. From fitting results, cross spectra with different roof’s curvature have similar trends. Therefore the case of rise/span ratio (f / D) equals 0.5 can be used instead of other three (f / D = 0.2, 0.3, 0.4) in conveneince. By separately regressing the fitted coefficients of root-coherence and phase functions, the cross spectra can be approximated well in a quantitative way.