Research

Surveying the damage after the Angus Tornado

Surveying the damage after the Angus Tornado

Dr. Kopp’s current interests focus on mitigating wind damage in extreme storms, such as tornadoes and hurricanes. This link to his TEDx Talk describes his research program, with further details provided below.

Current Research

Full-scale component and cladding tests at the IRLBH

Dr. Kopp with Dr. David Henderson, Dr. Murray Morrison, and Dr. Eri Gavanski (left to right) on the roof of the ‘3 Little Pigs’ test house at IRLBH.

Dr. Kopp with Dr. David Henderson, Dr. Murray Morrison, and Dr. Eri Gavanski on the roof of the ‘3 Little Pigs’ test house

The ‘3 Little Pigs’ project, named for the famous children’s story was developed to mitigate wind damage to houses during extreme storms such as tornadoes, thunderstorms and hurricanes. The research primarily takes place at the Insurance Research Lab for Better Homes (IRLBH). The focus on past research has been on the performance of residential roofs (both the complete roof structure as well as the sheathing) and residential wall systems (wood-frame walls, windows and glass, vinyl siding, brick-clad walls).

An overview of the project can be found in Kopp et al. (2010, The ‘Three Little Pigs’ Project: Hurricane Risk Mitigation by Integrated Wind Tunnel and Full-Scale Laboratory Tests, ASCE Natural Hazards Review, vol. 11, pp. 151-161). Unique pressure-based tests can be conducted using Pressure Loading Actuators, which replicate the effects of the wind in a very realistic way. This allows industry standard product tests to be assessed based on loads performed under more realistic conditions. The advantages of such methods are described by Kopp et al. (2012, Full-scale testing of low-rise, residential buildings with realistic wind loads, Journal of Wind Engineering and Industrial Aerodynamics, vol. 104-106, pp. 25-39).

Photo of the test house at IRLBH

Photo of the test house at IRLBH

Current projects are focussed on the performance of vinyl siding, for residential walls, and metal roofs, for commercial buildings. This is collaborative research involving State Farm, the Institute for Catastrophic Loss Reduction (ICLR), the Insurance Institute for Business and Home Safety (IBHS), and the Metal Building Manufacturers Association (MBMA).

Damage Surveys Following Tornadoes in Canada

UWO student, Emilio Hong, examining tornado damage in Angus, ON, June 2014.

UWO student, Emilio Hong, examining tornado damage in Angus, ON, June 2014.

Canada has the second highest rate of tornado occurrence in the world. Following severe tornadoes, Dr. Kopp’s rapid response research team participates in damage investigations. Dr. Kopp’s team is often on-site within hours following a damaging storm. Dr. Kopp also provides annual training on wind engineering principles of relevance to damage surveys, in collaboration with Environment and Climate Change Canada (ECCC) meteorologists, to the ECCC staff and UWO students who conduct the surveys. This research complements his full-scale lab testing at IRLBH and model-scale wind tunnel studies at BLWTL, providing ground-truth for test results and indications of where there are problems and further research is needed. Since the intensity of a tornado is rated by the damage it causes, Dr. Kopp’s lab research is also helping to guide modifications to the EF-Scale as applied in Canada. This research, which began in 2006, is on-going.

wind-borne debris damage to a vehicle from the EF-3 Tornado in Goderich, On

Wind-borne debris damage to a vehicle from the EF-3 Tornado in Goderich, ON

A recent paper by Kopp, (2017, Assessment of wind speeds based on damage observations from the Angus (Ontario) Tornado of 17 June 2014, Canadian Journal of Civil Engineering, vol. 44, pp. 37-47 doi: 10.1139/cjce-2016-0232) describes the findings from the 2014 tornado. The following link is to an ICLR Webinar by Dr. Kopp describing his team’s observations and findings from the EF-2-rated tornado in Angus, Ontario.

Wind Loads for Low-Rise Buildings and Small Building Components

The vast majority of buildings are low-rise, yet there has been relatively little research on the wind loads acting on these structures, particularly on houses. Dr. Kopp’s research group has, and is, working on every aspect of the nature of wind loading of low buildings and small building components. There are many challenges with such studies, particularly small components such as sheathing, cladding systems, soffits, etc., which often fail during severe storms.

Damage from the EF-2 Angus Tornado

Damage from the EF-2 Angus Tornado

Currently, Dr. Kopp’s team is working on methods to conduct wind tunnel studies with relatively large models at the Boundary Layer Wind Tunnel Laboratory (BLWTL), which requires careful evaluation of the factors that control the building aerodynamics. Details can be found in Kopp et al. (2014, Building components and cladding: recent developments and future possibilities for assessing of wind effects, Proceedings of the 11th United Kingdom Wind Engineering Society Conference, Birmingham, UK, pp. 79-84). The paper by Gavanski et al. (2013, Wind loads on roof sheathing of houses, Journal of Wind Engineering and Industrial Aerodynamics, vol. 114, pp. 106-121) won the American Association for Wind Engineering’s Best Paper Award (for papers in 2013). Kopp & Wu (2017) which was the AAWE Peter Irwin Lecture gives a framework for analyzing wind loads in tornadoes.

Wind Loads on Solar Arrays

Model house in the Boundary Layer Wind Tunnel Laboratory

Model house in the Boundary Layer Wind Tunnel Laboratory

Dr. Kopp has been working on wind loads on solar arrays for about 15 years, and his work has been used as the basis for current wind loading standards, particularly SEAOC-PV2-2012, ASCE 7-16 and NBCC.

Details on wind tunnel test methodologies can be found in Kopp and Banks (2013, Use of the wind tunnel test method for obtaining design wind loads on roof-mounted solar arrays, ASCE Journal of Structural Engineering, vol. 139(2), pp. 284-287), while detailed wind loads on roof-mounted arrays can be found in Kopp et al. (2012, Aerodynamic mechanisms for wind loads on tilted, roof-mounted, solar arrays, Journal of Wind Engineering and Industrial Aerodynamics, vol. 111, pp. 40-52) and Kopp (2014, Wind loads on low profile, tilted, solar arrays placed on large, flat, low-rise building roofs, ASCE Journal of Structural Engineering, vol. 140(2), doi: 10.1061/(ASCE)ST.1943-541X.0000821). Fundamental aerodynamics have been investigated by Pratt and Kopp (2013, Velocity measurements around low-profile, tilted, solar arrays mounted on large flat-roofs, Journal of Wind Engineering and Industrial Aerodynamics, vol. 123, part A, pp. 226-238, doi: 10.1016/j.jweia.2013.09.001).

Wind tunnel model of a house with a solar array on the roof

Wind tunnel model of a house with a solar array on the roof

Much of this research has been conducted in collaboration with commercial rack-mounting manufacturers. Current research is focussed on residential, roof-mounted arrays.

Wind Loads on Multi-layer Roof and Wall Systems

This is fundamental research on the nature of wind loads on multi-layer roof and wall cladding systems. This work has informed applied research on vinyl siding, solar arrays, and commercial (high-rise) cladding systems. A recent publication can be found in Oh and Kopp (2014, Modelling of spatially and temporally-varying cavity pressures in air permeable, double-layer roof systems, Building and Environment, vol. 82, pp. 135-150, doi: 10.1016/j.buildenv.2014.08.008). This work has been funded through Dr. Kopp’s NSERC Discovery Grant.

My Research Group

Current Students

Ph.D.

  • Nasiri, Mahshid; Jan. 2015 – pres. Thesis topic: Wind effects on metal roofs of low-rise buildings.
  • Miller, Connell; May. 2015 – pres. Thesis topic: Full-scale test methods for vinyl siding under wind loads.
  • Guo, Yitian; Sept. 2016 – pres. Thesis topic: Wind loads on gable and hip roofs.
  • Stevenson, Sarah; Sept. 2017 – pres. Thesis topic: Wind effects on housing in the Carribbean.
  • Xia, Jinlin; Jan. 2017 – pres. Dual PhD Degree student with Tongji University (jointly suppervised with Dr. Y. Ge) Thesis topic: Long-span bridge aerodynamics.
  • Hong, Emilio; Jan. 2018 – pres. Thesis topic: Damage indicators for destructive tornadoes.

M.E.Sc.

  • Jaffe, Aaron; May 2017 – present. Thesis: “Internal pressures in low-rise buildings during tornadoes.”.
  • Tanjil, Mahbub; Sept. 2017 – present. Thesis: “Effects of turbulence on gas flares”.

Postdoctoral Fellows

  • Akon, Abul Fahad; May 2017 – Apr. 2018. Mechanical & Materials Engineering, University of Western Ontario. Research topic: Building aerodynamics.
  • Wu, Chieh-Hsun; Sept. 2017 – Aug. 2018. Civil & Environmental Engineering, University of Western Ontario. Research topic: Design wind loads for low-rise buildings in tornadoes.

Research Staff

  • Corbin, Darcy; Jan. 2017 – present; Research Engineer. Topic: Wind tunnel modifications and equipment for Flare Net.
  • Jaffe, Aaron; July, 2018 – present; Research Engineer. Topic: Northern Tornadoes Project.
  • Elliott, Lesley; May 2018 – present; Research Meteorologist. Topic: Northern Tornadoes Project.

Alumni

Ph.D.

  • Chen, Yingzhao; Jan. 1999 – Aug. 2002; principal supervisor (co-supervised by D. Surry). Thesis: “Time Series Simulations of Wind-Induced Pressures on Low Buildings”.
  • Carriveau, Rupp; Jan. 2000 – Aug. 2004; co-supervisor (principal supervisor R.E. Baddour). Thesis: “Formation mechanisms of hydraulic intake vortices”.
  • Terrés-Nicoli, José; Oct. 2002 – Dec. 2008; at the University of Granada, Spain; co-supervisor (principal supervisor M.A. Losada). Thesis: “Mechanisms of Vortex-Induced Vibration of Bridges”.
  • Banik, Sudhan; Sept. 2003 – Aug. 2008; co-supervisor (principal supervisor H.P. Hong). Thesis: “Tornado hazard assessment”.
  • Liu, Zhigang; Sept. 2003 – Oct. 2009. Thesis: “Effects of geometry on vortex shedding from elongated bluff bodies.”
  • Gavanski, Eri; Sept. 2005 – Sept. 2009. Thesis: “Behaviour of glass plates under wind loads”.
  • Kordi, Bahareh; Sept. 2005 – Dec. 2009. Thesis: “Aerodynamics of wind-borne plate debris”.
  • Sarathi, Partha; Sept. 2005 – Dec. 2009; principal supervisor (co-supervised by P.J. Sullivan). Thesis: “Experimental study of the scalar concentration field in turbulent flows”.
  • Morrison, Murray; May 2006 – Sept. 2010. Thesis: “Response of a two-storey residential house under realistic, fluctuating wind loads”.
  • Henderson, David; Sept. 2006 – May 2010 at the James Cook University, Australia; co-supervisor (principal supervisor J. Ginger). Thesis: “Response of pierced, fixed, meal roof cladding to fluctuating wind loads”.
  • Taylor, Zachary; Sept. 2006 – Sept. 2011. Thesis: “The mechanisms of vortex shedding around elongated bluff bodies”.
  • Kirchhefer, Adam; Sept. 2007 – Dec. 2012; principal supervisor (co-supervised by R. Gurka, Ben Gurion University). Thesis: “The near wake of a European Starling”.
  • Stenabaugh, Sarah; Sept. 2009 – Apr. 2015; Thesis: “Design wind loads for solar modules mounted parallel to the roof of a low-rise building”.
  • Oh, Jeong Hee; Sept. 2010 – Aug. 2014. Thesis: “Wind-induced pressures in air permeable, double-layer roof systems in regions of separated flow”.
  • Van Straaten, Randy; Sept. 2010 – Aug. 2017. Thesis: “Pressure equalization of wind-induced pressures on residential vinyl siding ”.
  • Akon, Abul Fahad; Sept. 2012 – Apr. 2017. Thesis: “Effects of turbulence on the spearating-reattaching flow above surface-mounted, three-dimensional bluff bodies ”.
  • Wu, Chieh-Hsun (Jason); May 2013 – Aug. 2017. Thesis: “Estimation of turbulence effects on wind-induced suctions on the roof of a low-rise building ”.

M.E.Sc.

  • Carriveau, Rupp; Sept. 1999 – Jan. 2000; co-supervisor (principal supervisor R.E. Baddour). Thesis: “Investigation of Dye-Core Vortices at Submerged Water Intakes”.
  • Bailey, Sean; Sept. 1999 - May 2001; co-supervisor (principal supervisor R.J. Martinuzzi). Thesis: “The effects of wall proximity on vortex shedding from a square cylinder”.
  • Mans, Christian; Sept. 1999 – Aug. 2001; principal supervisor (co-supervised by D. Surry). Thesis: “Wind loads on parapets”.
  • Ellison, Tanya; May 1999 – Jan. 2002; jointly-supervised with R. J. Martinuzzi. Thesis: “High turbulence intensity wake measurements with a four-wire probe”.
  • Blissitt, Mark; Sept. 1999 – Jan. 2002. Thesis: “Experimental investigation of a uniform turbulent shear flow with multi-wire thermal anemometry”.
  • St. Pierre, Lizeanne; May 2000 - May 2002; principal supervisor (co-supervised by D. Surry). Thesis: “Evaluation of wind load provisions for low buildings”.
  • Pande, Mohit; Sept. 2000 – Aug. 2002; co-supervisor (principal supervisor D. Surry). Thesis: “Hurricane windfield simulations”.
  • Terrés-Nicoli, José; Sept. 2000 – Oct. 2002; principal supervisor (co-supervised by J.P.C. King). Thesis: “The torsional vortex-induced response of the Storebaelt Bridge”.
  • Farquhar, Steve; May 2001 - May 2003; principal supervisor (co-supervised by D. Surry). Thesis: “Wind tunnel and uniform pressure testing of a standing seam metal roof model”.
  • Sham bin Dol, Sharul; Jan. 2003 - June 2004; co-supervisor (principal supervisor R.J. Martinuzzi). Thesis: “The suppression of periodic vortex shedding from a rotating circular cylinder”.
  • Oh, Jeong Hee; Jan. 2003 – Dec. 2004; jointly-supervised with D.R. Inculet. Thesis: “Wind-induced internal pressures in low-rise buildings”.
  • Holmes, Bill; May 2002 – Oct. 2005; co-supervisor (principal supervisor R.J. Martinuzzi). Thesis: “Experimental investigation of velocities downstream of an axial flow fan for guide vane design”.
  • Morrison, Murray; Aug. 2004 – April 2006; co-supervisor (principal supervisor R.J. Martinuzzi). Thesis: “Vortex shedding from small apex angle pyramids”.
  • Palombi, Emanuela; Sept. 2004 – Sept. 2006; principal supervisor (co-supervised by R. Gurka). Thesis: “Effects of geometry on the flow around elongated cylinders”.
  • Nywening, Mark; Sept. 2004 – Dec. 2006; principal supervisor (co-supervised by T.C.E. Ho). Thesis: “The effects of geometry on wind loads of low-rise buildings”.
  • Khan, Abrar; Sept. 2010 – Oct. 2012. Thesis: “Load sharing of toe-nailed, roof-to-wall connections under extreme wind loads in wood-frame houses”.
  • Pratt, Nicolas; Jan. 2011 – Dec. 2012. Thesis: “Wind field measurements around photovoltaic panel arrays mounted on large flat roofs”.
  • Stedman, Derek; May 2012 – Apr. 2014. Thesis: “Full-scale tests of a wood-frame structure under extreme wind loads”.
  • Hong, Emilio; May 2015 – Apr. 2017. Thesis: “Wall pressure coefficients for low-to high-rise buildings”.
  • Sreedevi, Rahul, P; May 2015 – Apr. 2017. Thesis: “Estimation of cavity pressures in air-ermeable multi-layer systems using a lumped leakage approach”.
  • Stevenson, Sarah; Sept. 2015 – Aug. 2017. Thesis: “Analysis of framing failures in wood-frame residential roofs under wind load”.
  • Fakhruzzaman, Arif; Sept. 2015 – Aug. 2017. Thesis: “Influence of turbulence on the aerodynamics of low-rise buildings”.

M.Eng.

  • Quiroga, Patricia; Sept. 2003 – Apr. 2006. Project: “Uncertainty analysis of surface pressure measurements on low-rise buildings”

Postdoctoral Fellows

  • Vernet, Anton; July 1998 – Aug. 1999; Mechanical Engineering, Universitat Rovira i Virgili, Spain. Research topic: Pattern recognition analysis of critical points in turbulent wakes.
  • Sistla, Phani; Nov. 2000 – Dec. 2002; Mechanical Engineering, Tennessee Tech University, USA; co-supervisor (principal supervisor R.J. Martinuzzi). Research topic: Suppression of vortex shedding in the wake of a rotating cylinder.
  • Chen, Yingzhao; Sept. 2002 – Aug. 2003; Civil & Environmental Engineering, University of Western Ontario. Research topic: Aerodynamics of low buildings.
  • Cho, Sang-Won; Feb. 2005 – Aug. 2006; Civil & Environmental Engineering, Korean Advanced Institute of Science and Technology; jointly-supervised with J. Galsworthy. Research topic: Wind loads on houses.
  • Banik, Sudhan; Dec. 2008 – Dec. 2009; Civil & Environmental Engineering, University of Western Ontario. Research topic: Effects of wind borne debris on glass panels.
  • Kordi, Bahareh; Jan. 2010 – Dec. 2010; Civil & Environmental Engineering, University of Western Ontario. Research topic: Wind loads on houses.
  • Sarathi, Partha; Jan. 2010 – June 2011; Civil & Environmental Engineering, University of Western Ontario. Research topic: Aerodynamics of low-rise buildings.
  • Gavanski, Eri; Sept. 2009 – Feb. 2011; Civil & Environmental Engineering, University of Western Ontario. Research topic: Performance of residential wall systems in extreme winds.
  • Liu, Zhigang; Jan. 2010 – Apr. 2010; Civil & Environmental Engineering, University of Western Ontario. Research topic: Vortex-induced response of elongated bluff bodies.
  • Henderson, David; June 2010 – Feb. 2011; Civil Engineering, James Cook University. Research topic: Performance of wood-frame houses under extreme winds.
  • Morrison, Murray; Oct. 2010 – Nov. 2011; Civil & Environmental Engineering, University of Western Ontario. Research topic: Reynolds number effects on wind loads on low-rise buildings.
  • Schinke, Reinhard; Sept. 2011 – Nov. 2011; Leibniz Institute of Ecological Urban and Regional Development Dresden, Germany. Research topic: Risk modeling of houses under extreme wind.
  • Guha, Tushar; Mar. 2012 – Oct. 2013; Mechanical Engineering, University of Aukland. Research topic: Analytical modelling of roof failures to houses in extreme wind.
  • Oh, Jeong Hee; Sept. 2014 – Dec. 2014; Civil & Environmental Engineering, University of Western Ontario. Research topic: Pressure equalization in multi-layer cladding systems.

Exchange Students

  • Fathi, Salim; Sept. 2000 - May 2001; Ph.D. student from University of Trieste, Trieste, Italy; with co-supervisor J. Galsworthy.
  • Cruzado, Hector; Aug. 2005 – Dec. 2005; Ph.D. student from Texas Tech University, Lubbock, Texas.
  • Mandava, Subba Rao; June 2006 – Oct. 2006; Ph.D. student from Universitat Rovira i Virgili, Spain.
  • Iida, Yumi, Sept. 2011 – Aug. 2012; Ph.D. student from Tohoku University, Japan
  • Yiu, Li, Sept. 2016 – Sept. 2017; Ph.D. student from Zhejiang University, China, (CSC Scholar)
  • Hao, Yanfeng, Sept. 2017 – Sept. 2018; Ph.D. student from Hunan University, China, (CSC Scholar)
  • Xia, Yuchao, Sept. 2017 – Sept. 2018; Ph.D. student from Zhejiang University, China, (CSC Scholar)