Browse > Article
http://dx.doi.org/10.12989/was.2012.15.2.111

Recent Brazilian research on thunderstorm winds and their effects on structural design  

Riera, Jorge D. (PPGEC, EE, Universidade Federal do Rio Grande do Sul)
Ponte, Jacinto Jr. (UNISINOS, Universidade do Vale do Rio dos Sinos)
Publication Information
Wind and Structures / v.15, no.2, 2012 , pp. 111-129 More about this Journal
Abstract
Codes for structural design usually assume that the incident mean wind velocity is parallel to the ground, which constitutes a valid simplification for frequent winds caused by sypnoptic events. Wind effects due to other phenomena, such as thunderstorm downbursts, are simply neglected. In this paper, results of recent and ongoing research on this topic in Brazil are presented. The model of the three-dimensional wind velocity field originated from a downburst in a thunderstorm (TS), proposed by Ponte and Riera for engineering applications, is first described. This model allows the generation of a spatially and temporally variable velocity field, which also includes a fluctuating component of the velocity. All parameters are related to meteorological variables, which are susceptible of statistical assessment. An application of the model in the simulation of the wind climate in a region sujected to both EPS and TS winds is discussed next. It is shown that, once the relevant meteorological variables are known, the simulation of the wind excitation for purposes of design of transmission lines, long-span crossings and similar structures is feasible. Complementing the theoretical studies, wind velocity records during a recent TS event in southern Brazil are presented and preliminary conclusions on the validity of the proposed models discussed.
Keywords
thunderstorms; winds; downdraft; downburst; vertical profile; fluctuating velocities; mixed climate; extreme values; registered velocities;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)  (Related Records In Web of Science)
연도 인용수 순위
1 ABNT- Associacao Brasileira de Normas Tecnicas (1987), Norma NBR-6123 ,Acao do Vento nas Edificacoes, Rio de Janeiro.
2 ABNT- Associacao Brasileira de Normas Tecnicas (1991) , NBR - 5419 , Protecao de estruturas contra descargas atmosfericas, Rio de Janeiro.
3 AS1170.2 (2002), Structural design actions -Part 2 -Wind actions
4 AS/NZS 7000 (2010), Overhead Line Design - Detailed Procedures
5 ASCE Manual 74, Guidelines for Electrical Transmission Line Structural Loading
6 Blessmann, J. (1995), O Vento na Engenharia Estrutural, Editora da Universidade, 1a Edicao, Porto Alegre, RS, Brasil.
7 Caracena,F., Holle.R.L. and Dosswell, C.A. (1977), Microbursts: A handbook for visual identification, NOAA, National Severe Storm Laboratories, U.S.A.
8 CIGRE SC22 WG16 (2002), Meteorology for overhead lines, Draft Report on Current Practices regarding Frequencies and Magnitude of High Intensity Winds.
9 CIGRE TB 256 (2004), Report on Current Practices regarding the Frequencies and Magnitude of High Intensity Winds.
10 CIGRE TB 350 (2008), How Overhead Lines Respond to Localized High Intensity Winds - Basic Understanding.
11 Chay, MT., Albermani, F. and Wilson, B. (2006), "Numerical and analytical simulation of downburst wind loads", Eng. Struct., 28(2), 240-254.   DOI
12 Chen, Lizhong , Letchford, C.W. (2004), "A deterministic-stochastic hybrid model of downburst and its impact on a cantilevered structure", Eng. Struct., 26(5), 619-26.   DOI
13 Donald, A.T. and Fox, Robert W. (1995), Introducao a Mecanica dos Fluidos, Editora Guanabara- Koogan S.A., 4a. Edicao.
14 Fujita,T.T. (1978), Manual of downburst identification for Project NIMROD, SMPR- 156, University of Chicago, May.
15 Fujita.,T.T. (1985), The Downburst Microburst and Macroburst, Report of projects NIMROD and JAWS.
16 Gomes, L. and Vickery, B.J. (1976), On thunderstorm wind gusts in Australia, with particular reference to Observatory Hill, Sydney, Research Report No. R277, Civil Engineering Laboratory, University of Sydney.
17 Holmes, J.D. and Oliver, S.E. (2000), "An empirical model of a downburst", Eng. Struct., 22(9),1167-72.   DOI
18 Holmes, J.D, Baker, C.J., English, E.C. and Choi, E.C.C.(2005), "Wind structures and codification", Wind Struct., 8(4), 235-250.   DOI
19 Holmes, J.D., Hangan, H., Schroeder, J., Letchford, C.W. and Orwig, K.D. (2008), "A forensic study of the Lubbock-Reese dowwwndraft of 2002", Wind Struct., 11(2), 137-152.   DOI
20 Orwig, K.D. and Schroeder, J.L. (2007), "Near-surface wind characteristics of extreme thunderstorm winds", J. Wind Eng. Struct. Aerod., 95(7), 565-584.   DOI
21 Oseguera, R.M. and Bowles, R.L. (1988), A simple analytic 3-dimensional downburst model based on boundary layer stagnation flow, NASA Technical Memorandum 100632, July 1988.
22 Paluch,M.J., Toazza, A., Rocha, M.M. and Marroquim, A.I. (2003), "O laboratorio anemometrico da Universidade de Passo Fundo", Proceedings of the III Workshop Brasileiro de Micrometeorologia; UFSM, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil.
23 Paluch, M.J., Cappellari, T.T.O. and Riera, J.D. (2007), "Experimental and numerical assessment of EPS wind action on long span transmission line conductors", J. Wind Eng. Ind. Aerod., 95(7), 473-492.   DOI
24 Puglia, V.B. and Ramires, L.(2010), Analise de uma tormenta TS, Relatorio Tecnico, PPGEC, UFRGS, Porto Alegre, RS, Brasil.
25 Ponte Jr., Jacinto (2006), Modelagem e Simulacao do Campo de Velocidades do Vento em Tormentas Eletricas, Tese de Doutorado. Promec, UFRGS., Porto Alegre, RS, Brasil, 2005.
26 Ponte Jr., J. and Riera, J.D. (2007),"Wind velocity field during thunderstorms", Wind Struct., 10(3), 287-300.   DOI
27 Ponte, Jr., J. and Riera, J.D. (2010), "Simulation of extreme wind series caused by thunderstorms in temperate latitudes", Struct. Saf., 32(4), 131-137.
28 Riera, J.D., Viollaz, A.J. and Reimundin, J.C. (1977),"Some recent results on probabilistic models of extreme wind speeds", J.Wind Eng. Struct. Aerod., 2(3), 271-287.   DOI
29 Riera, J.D. and Nanni, L.F. (1989), "Pilot study of extreme wind velocities in a mixed climate considering wind orientation", J. Wind Eng. Struct. Aerod., 32(1-2), 11-20.   DOI
30 Riera, J.D., Viegas, F.B. and dos Santos, M.L.W. (1989) "Probabilistic assessment of wind loading for structural analysis", Proceedings of the 5th International Conference on Structural Safety and Reliability, ICOSSAR'89, Innsbruck, Austria, Balkem, Rotterdam.
31 Riera , J.D. and Rocha, M.M. (1998), "Load definition for wind design and reliability assessments; extreme wind climate", in Wind Effects on Buildings and Structures, (Eds., J.D. Riera and A.G. Davenport), A.A. Balkema, Rotterdam.
32 Simiu, E. and Scanlan, R.H. (1996), Wind Effects on Buildings and Structures, 3rd Ed., John Wiley & Sons, Inc., New York, USA.
33 Thom, H.C.S. (1967), Toward a universal climatological extreme wind distribution, Wind Effects on Buildings and Structures, Ottawa, Canada, Univ. of Toronto Press.
34 Vicroy, D.D. (1991), A simple, analytical, axisymmetric microburst model for downdraft estimation", NASA TM-104053, DOT/FAA/RD, 91/10, Feb.
35 Vicroy, D.D. (1992), "Assessment of microburst models for downdraft estimation", J. Aircraft, 29(6), 1043-1048.   DOI
36 Zhu,S. and Etkin, B. (1985), "Model of the wind field in a downburst", J. Aircraft, 22(7), 595-601, July 1985.   DOI
37 Wood, G.S. and Kwok, C.S. (1998), "An empirically derived estimate for the mean velocity profile of a thunderstorm downburst", Proceedings of the 7 th AWES Workshop, Auckland, Australia.