DOI QR코드

DOI QR Code

Ridge and field tile aerodynamics for a low-rise building: a full-scale study

  • Tecle, Amanuel (Laboratory for Wind Engineering Research (LWER), International Hurricane Research Center (IHRC)/Department of Civil and Environmental Engineering (CEE), Florida International University (FIU)) ;
  • Bitsuamlak, Girma T. (WindEEE Research Institute, Western University) ;
  • Suskawang, Nakin (LWER, IHRC/CEE) ;
  • Chowdury, Arindam Gan (LWER, IHRC/CEE) ;
  • Fuez, Serge (Laboratory for Wind Engineering Research (LWER), International Hurricane Research Center (IHRC)/Department of Civil and Environmental Engineering (CEE), Florida International University (FIU))
  • Received : 2011.06.27
  • Accepted : 2012.04.24
  • Published : 2013.04.25

Abstract

Recent major post-hurricane damage assessments in the United States have reported that the most common damages result from the loss of building roof coverings and subsequent wind driven rain intrusion. In an effort to look further into this problem, this paper presents a full-scale (Wall of Wind --WoW--) investigation of external and underneath wind pressures on roof tiles installed on a low-rise building model with various gable roofs. The optimal dimensions for the low-rise building that was tested with the WOW are 2.74 m (9 ft) long, 2.13 m (7 ft) wide, and 2.13 m (7 ft) high. The building is tested with interchangeable gable roofs at three different slopes (2:12; 5:12 and 7:12). The field tiles of these gable roofs are considered with three different tile profiles namely high (HP), medium (MP), and low profiles (LP) in accordance with Florida practice. For the ridge, two different types namely rounded and three-sided tiles were considered. The effect of weather block on the "underneath" pressure that develops between the tiles and the roof deck was also examined. These tests revealed the following: high pressure coefficients for the ridge tile compared to the field tiles, including those located at the corners; considerably higher pressure on the gable end ridge tiles compared to ridge tiles at the middle of the ridge line; and marginally higher pressure on barrel type tiles compared to the three-sided ridge tiles. The weather blocking of clay tiles, while useful in preventing water intrusion, it doesn't have significant effect on the wind loads of the field tiles. The case with weather blocking produces positive mean underneath pressure on the field tiles on the windward side thus reducing the net pressures on the windward surface of the roof. On the leeward side, reductions in net pressure to a non-significant level were observed due to the opposite direction of the internal and external pressures. The effect of the weather blocking on the external pressure on the ridge tile was negligible.

References

  1. ASTM E 1592 (2005), Standard Test Method for Structural Performance of Sheet Metal Roof and Siding Systems by Uniform Static Air Pressure Difference.
  2. Banks, D. and Meroney, R.N. (2001), "A model of roof-top surface pressures produced by conical vortices: model development", Wind Struct., 4(3), 227-246. https://doi.org/10.12989/was.2001.4.3.227
  3. Bitsuamlak, G.T., Dagnew, A. and Chowdhury, A. (2009), "Computational assessment of blockage and wind simulator proximity effects for a new full-scale testing facility", Wind Struct. (in press)
  4. Cochran, L.S. and Cermark, J.E. (1992), "Full-and model-scale cladding pressures on the Texas Tech Experimental Building", J. Wind Eng. Ind. Aerod., 43, 1589-1600. https://doi.org/10.1016/0167-6105(92)90374-J
  5. Cochran, L.S., Levitan, M.L., Cermark, J.E. and Yeatts, B.B. (1993), "Geometric similitude applied to model and full-scale pressure tap sizes", Proceedings of the 3rd Asia-Pacific Symp on Wind Eng., 917 922, HK.
  6. Cutter, S.L., Johnson, L.A., Finch, C. and Berry, M. (2007), "The US hurricane coasts: increasingly vulnerable? ", Environment 49(7), 8-20.
  7. Factory Mutual Research Corporation (FM) (1985), "Factory mutual property loss prevention data sheet 1-49 - Perimeter flashing", Factory Mutual, Norwood, MA, USA.
  8. Federal Emergency Management Agency (FEMA) (2004), Improving school safety, Risk Management Series design guides, FEMA RMS #424, January, USA.
  9. Federal Emergency Management Agency (FEMA) (2007), Improving critical facility safety, Risk Management Series design guides, FEMA RMS #543, January, USA.
  10. FM 4470 (1986), Approval Standard for Class 1 Roof Covers.
  11. Gerhardt, H.J. and Kramer, C. (1992), "Effects of building geometry on roof wind loading", J. Wind Eng. Ind. Aerod., 43, 1765-1773. https://doi.org/10.1016/0167-6105(92)90589-3
  12. Hooke, W.H. (2007), "Editor's note", Nat. Academy Eng., 37(1), 3-4.
  13. Huang, P., Mirmiran, A., Chowdhury, A.G., Abishdid, C. and Wang, T. (2009), "Performance of roof tiles under simulated hurricane impact", J. Architec. Eng.-ASCE, 15(1), 26-34. https://doi.org/10.1061/(ASCE)1076-0431(2009)15:1(26)
  14. Institute of Business and Home Safety (IBHS) (1999a), Metal edge flashing, Natural Hazard Mitigation Insights, No.10, June, USA.
  15. Institute of Business and Home Safety (IBHS) (1999b), Performance of metal buildings in high winds, Natural Hazard Mitigation Insights, No. 9, January, USA.
  16. Institute of Business and Home Safety (IBHS) (2009), Hurricane IKE: nature's force vs structural strength, Natural Hazard Mitigation Insights, No. 9, January 1999, USA.
  17. Kawai, H. and Nishimura, G. (1996), "Characteristics of fluctuating suction and conical vortices on a flat roof in oblique flow", J. Wind Eng. Ind. Aerod., 60, 211-225. https://doi.org/10.1016/0167-6105(96)00035-9
  18. Kramer, C. and Gerhardt, H.J. (1989), "Wind pressures on roofs of very low and very large industrial buildings", Proceedings of the 8th Colloq. on Industrial Aerodyn. Part 2. Aachem, Germany.
  19. Lin, J.X. and Surry, D. (1998), "The variation of peak loads with tributary area near corners on flat low building roofs", J. Wind Eng. Ind. Aerod., 77-78, 185-196. https://doi.org/10.1016/S0167-6105(98)00142-1
  20. Lin, J.X., Surry, D. and Tieleman, H.W. (1995), "The distribution of pressure near roof corners of flat roof low buildings", J. Wind Eng. Ind. Aerod., 56, 235-265. https://doi.org/10.1016/0167-6105(94)00089-V
  21. Lott, N. and Ross, T. (2006), "Tracking and evaluating U.S. billion dollar weather disasters, 1980-2005", Forum on Environmental Risk and Impacts on Society: Successes and Challenges, American Meteorological Society.
  22. McDonald, J.R. and Smith, T.L. (1990), Performance of roofing systems in the hurricane Hugo, Institute for Disaster Research, Texas Tech University, Lubbock, Texas.
  23. Mehta, K.C. and Levitan, M.L. (1992), "Roof corner pressures measured in the field on a low building", J. Wind Eng. Ind. Aerod., 41, 181-192. https://doi.org/10.1016/0167-6105(92)90408-3
  24. Minor, J.E. and Mehta, K.C. (1979), "Wind damage observations and implications", J. Struct. Division -ASCE, 11, 2279-2291.
  25. Mirmiran, A. (2006), "Hurricane loss reduction for housing in Florida: Section 5-Performance of tile roofs under hurricane impact - Phase I", Retrieved June 10, 2010, from http://www.ihrc.fiu.edu/lwer/docs/Year6_Section5_TileTest_RCMPY6.pdf.
  26. Mirmiran, A., Wang, T., Abishdid, C., Huang, P., Jimenez, D.L. and Younes, C. (2007), "Hurricane loss reduction for housing in Florida: performance of tile roofs under hurricane impact - Phase II", Retrieved June 11, 2010, http://www.ihrc.fiu.edu/lwer/docs/Year7_Section5_Tiles_ RCMPY7.pdf.
  27. Rappaport, E.N. (2000), "Loss of life in the United States associated with recent tropical cyclones", Bull. Am. Meteorol. Soc., 81(9), 2065-2074. https://doi.org/10.1175/1520-0477(2000)081<2065:LOLITU>2.3.CO;2
  28. Robertson, A.P., Hoxey, R.P., Rideout, N.M. and Freathy, P. (2007), "Full-scale study of wind loads on roof tiles and felt underlay and comparisons with design data", Wind Struct., 10(6), 495-510. https://doi.org/10.12989/was.2007.10.6.495
  29. Saathoff, P.J. and Melboume, W.H. (1989), "The generation of peak pressures in separated /reattaching flows", J. Wind Eng. Ind. Aerod., 32, 121-134. https://doi.org/10.1016/0167-6105(89)90023-8
  30. Sparks, P.R., Schiff, S.D. and Reinhold, T.A. (1994), "Wind damage to envelopes of houses and resulting insurance losses", 53, 145-155.
  31. Stathopoulos, T. (1987), "Wind pressures on flat roof edges and corners", Proceedings of the 7th Int. Conf. on Wind Eng. Aachen, Germany.
  32. Stathopoulos, T., Baskaran, A. and Goh, P.A. (1990), "Full-scale measurements of wind pressures on flat roof corners", J. Wind Eng. Ind. Aerod., 36, 1063-1072. https://doi.org/10.1016/0167-6105(90)90103-J
  33. Tieleman, H.W., Surry, D. and Lin, J.X. (1994), "Characteristics of mean and fluctuating pressure coefficients under corner (delta wing) vortices", J. Wind Eng. Ind. Aerod., 42, 263-275.
  34. UL 1897 (2004), Standard for Uplift Tests for Roof Covering Systems.

Cited by

  1. Partial turbulence simulation and aerodynamic pressures validation for an open-jet testing facility vol.19, pp.1, 2014, https://doi.org/10.12989/was.2014.19.1.015
  2. Wind pressure characteristics of a low-rise building with various openings on a roof corner vol.21, pp.1, 2015, https://doi.org/10.12989/was.2015.21.1.001
  3. Investigating a wind tunnel method for determining wind-induced loads on roofing tiles vol.155, 2016, https://doi.org/10.1016/j.jweia.2016.05.006
  4. Wind loading on ridge, hip and perimeter roof tiles: A full-scale experimental study vol.166, 2017, https://doi.org/10.1016/j.jweia.2017.04.002