Wind effects on a large cantilevered flat roof: loading characteristics and strategy of reduction
Mean and extreme pressure distributions on a large cantilevered flat roof model are measured in a boundary layer wind tunnel. The largest peak suction values are observed from pressure taps beneath conical "delta-wing type" corner vortices that occur for oblique winds, then the characteristics and causes of the local peak suctions are discussed in detail. Power spectra of fluctuating wind pressures measured from some typical taps located at the roof edges under different wind directions are presented, and coherence functions of fluctuating pressures are also obtained. Based on these results, it is verified that the peak suctions are highly correlated with the conical vortices. Furthermore, according to the characteristics of wind loads on the roof, an aerodynamic solution to minimize the peak suctions by venting the leading edges and the corners of the roof is recommended. The experimental results show that the suggested strategy can effectively control the generation of the conical vortices and make a reduction of 50% in mean pressures and 25% in extreme local pressures at wind sensitive locations on the roof.
- Uematsu, Y., Yamada, M. and Sasaki, A. (1997), "Design wind loads for structural frames of flat long-span roofs: gust loading factor for a structurally integrated type", J. Wind Eng. Ind. Aerodyn., 66, 155-168.
- Wind Tunnel Testing: A General Outline. The Boundary Layer Wind Tunnel Laboratory, The University of Western Ontario, Faculty of Engineering Science, London, Ontario, Canada N6A 5B9, May 1999.
- Xie, Z.N., Ni, Z.H. and Shi, B.Q. (2002), "Dynamic characteristics of tubing systems for fluctuating wind pressure measurements", Chinese Journal of Applied Mechanics, 19(1), 5-9. (in Chinese).
- Yasui, H., Marukawa, H., Katagiri, J., Katsumura, A., Tamura, Y. and Watanabe, K. (1999), "Study of windinduced response of long-span structure", J. Wind Eng. Ind. Aerodyn., 83, 277-288.
- Simiu, E. and Scanland, R.H. (1978), Wind Effects on Structures: An Introduction to Wind Engineering, New York: John Wiley.
- Stathopoulos, T. and Surry, D. (1983), "Scale effects in wind tunnel testing of low buildings", J. Wind Eng. & Ind. Aerodyn., 13, 313-326.
- Surry, D. (1982), "Consequences of distortions in the flow including mismatching scale and intensities of turbulence", Workshop on Wind Tunnel Modeling for Civil Engineering Applications. U. S. Dept. of Commerce, National Bureau of Standards, Gaithersburg, MD, U. S. A.
- Uematsu, Y. and Yamada, M. (2002), "Wind-induced dynamic response and its load estimation for structural frames of circular flat roofs with long spans", Wind and Struct., An Int. J., 5(1), 49-60.
- Uematsu, Y., Watanabe, K., Sasaki, A., Yamada, M. and Hongo, T. (1999), "Wind-induced dynamic response and resultant load estimation of a circular flat roof", J. Wind Eng. Ind. Aerodyn., 83, 251-261.
- Li, Q.S. and Melbourne, W.H. (1999b), "Turbulence effects on surface pressures of rectangular cylinders", Wind and Structures, 2(4), 253-266.
- Li, Q.S., Calderone, I. and Melbourne, W.H. (1999), "Probabilistic characteristics of pressure fluctuations in separated flows for various free-stream turbulence", J. Wind Eng. Ind. Aerodyn., 82, 125-145.
- Melbourne, W.H. (1975), "The relevance of codification to design", Proc. 4th Int. Conf. on Wind Effects on Building and Structures, Heathrow, 785-790.
- Melbourne, W.H. (1979), "Turbulence effects on maximum surface pressures - a mechanism and possibility of reduction", Proc. 5th Int. Conf. on Wind Engineering, Fort Collins, 541-552.
- Melbourne, W.H. (1995), "The response of large roofs to wind action", J. Wind Eng. Ind. Aerodyn., 54/55, 325-335.
- Melbourne, W.H. and Cheung, J.C.K. (1988), "Reducing the wind loading on large cantilevered roof", J. Wind Eng. & Ind. Aerodyn., 28, 410-410.
- Natalini, B., Marighetti, J.O. and Natalini, M.B. (2002). "Wind tunnel modeling of mean pressures on planar canopy roof", J. Wind Eng. & Ind. Aerodyn., 90, 427-439.
- GB50009-2001 (2002), "Load code for the design of building structures", China Architecture & Building Press, Beijing. (in Chinese).
- Hunt, A. (1981), Scale Effects on Wind Tunnel Measurements of Wind Effects on Prismatic Buildings, PhD Thesis, Cranfield Institute of Technology, UK.
- Kawai, H. (2002), "Local peak pressure and conical vortex on building", J. Wind Eng. Ind. Aerodyn., 90, 251-263.
- Kawai, H. and Nishimura, G. (1996), "Characteristics of fluctuating suction and conical vortices on a flat roof in oblique flow", J. Wind Eng. Ind. Aerodyn., 60, 211-225.
- Li, Q.S. and Melbourne, W.H. (1999a), "The effects of large scale turbulence on pressure fluctuations in separated and reattaching flows", J. Wind Eng. Ind. Aerodyn., 83, 159-169.
- Banks, D., Meroney, R.N., Sarkar, P.P., Zhao, Z. and Wu, F. (2000), "Flow visualization of conical vortices on flat roofs with simultaneous surface pressure measurement", J. Wind Eng. Ind. Aerodyn., 84, 65-85.
- Cook, N.J. (1982), "Reduction of wind loads on a grandstand roof", J. Wind Eng. Ind. Aerodyn., 10, 373-380.
- Uematsu, Y., Yamada, M. and Sasaki, A. (1996), "Wind-induced dynamic response and resultant load estimation for a flat long-span roof", J. Wind Eng. Ind. Aerodyn., 65, 155-166.
- Uematsu, Y. and Isyumov, N. (1999), "Wind pressures acting on low-rise buildings", J. Wind Eng. Ind. Aerodyn., 82, 1-25.
- AIJ Recommendations for Loads on Buildings (1996), Architectural Institute of Japan, Japan. (English version).
- Li, Q.S. and Melbourne, W.H. (1995), "An experimental investigation of the effects of free-stream turbulence on streamwise surface pressures in separated and reattaching flows", J. Wind Eng. Ind. Aerodyn., 51-52, 313-323.
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