Comparison of model/full-scale wind pressures on a high-rise building

Abstract

/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. Aerodynamics, 1, pp. 55-66, 1975 Comparison of model/full-scale wind pressures on a high-rise building Dalgliesh, W. A. Journal of Industrial.v'p a ",' e, ex gcfi\ Journal of Industrial Aerodynamics, 1 (1975) (Received November 14,1974) Summary Recent experience with wind-induced glass breakage in high-rise office towers has demonstrated the difficulty of pin-pointing potential problem areas on a building and hence the need for a better understanding of the magnitude and nature of cladding loads.55-66 , a q * ; k: d o Elsevier Scientific Publishing Company, Amsterdam -Printed in T?qNet'Results of surface wind pressure measurements made simultaneously at 32 points on a 57-storey office tower in Toronto are reported. In addition to readings taken at %-second intervals during high winds, mean and root-mean-square pressures were recorded for a 5-minute interval once each hour, and pressure coefficients referred to the free stream dynamic pressure at 286 m were computed for comparison with wind tunnel test information which was used in the design of the cladding.

Full-Scale/Model Test Comparisons to Validate the Traditional ABL Wind Tunnel Simulation Technique: A Literature Review

“…Typical discrepancies were: (1) Mean and peak negative pressures at corners and separated flow regions on low-rise building roofs were underestimated in wind tunnels [7,12,[18][19][20]24]; (2) Local fluctuating pressures attributable to vortex shedding on high-rise building models differed from those on the prototype [27]; (3) Aero-elastic model tests for high-rise buildings underestimated the dynamic structural responses in the intermediate-frequency range [4]; (4) Differences between rms accelerations measured on the location and those obtained from the force balance model test were in the range of 4-25% for high-rise buildings [32,[34][35][36][37]; (5) Long-span bridges' vertical VIV amplitudes obtained using section models and full bridge aero-elastic models were much lower than those observed on the location [42,44]; (6) The pressure fluctuations measured on real structures followed non-Gaussian distributions, while the corresponding samples obtained from model tests followed Gaussian distribution [37,47,48,50]; (7) Model test results were conservative with respect to the spectral characteristics of wind-induced pressures measured on building models [17,50], since the normalized pressure spectra obtained in the wind tunnel were usually higher at high-frequency ranges than the full-scale values, and the coherences between pressure fluctuations tended to be stronger in the wind tunnel than at full scale. Taking a step forward, many related researchers explained the causes of the observed differences:…”

“…Dalgliesh [27] thought that reasons for the discrepancy between full-scale measurement and model test results for a high-rise building were that full-scale winds were not frequent enough or strong enough to provide sufficiently reliable rms data, and unsteadiness existed in the full-scale wind direction. Dalgliesh [4] supposed that full-scale experiments were inherently less deterministic and accurate than the wind tunnel experiments they were supposed to validate, since field observations were subjected to so many uncontrolled variables.…”

“…Examples were found of excellent agreement in almost all respects, but for some wind directions the comparisons gave unsatisfactory correlations. Dalgliesh [27] made simultaneous surface wind pressure measurements at 32 points on a 57-storey office tower in Toronto. Mean and rms pressures were recorded, and pressure coefficients referred to the free stream dynamic pressure at 286 m were computed for comparison with wind tunnel test information.…”

Full scale measurements and simulations of the wind speed in the close proximity of the building skin

“…On the other hand, full scale experiments are limited with the availability of sufficient wind conditions, large amount of time, effects of surrounding terrain, measuring devices and involved costs. Full scale measurements on city buildings, where the fluctuating characteristics of wind were subject of investigation, have been performed in many countries [3,4,5,6]. …”

The Use of Wind Tunnel Measurements in Building Design

“…Modern finite element methods and sets of directional wind tunnel pressure data obtained simultaneously at large numbers of taps have been applied recently to obtain such estimates for rigid buildings (Jang at al., 2002;Duthinh et al, 2008). Dalgliesh (1975), Dalgliesh (1982) and Dalgliesh et al (1983) compared measurements of wind pressure at full-scale and on a 1/200 aeroelastic wind tunnel model of the Commerce Court West Tower in Toronto. The 57-story steel frame (36.5 m x 69.7 m x 239 m) was the tallest building in Canada when it was completed in 1973.…”