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He’ll Huff and He’ll Puff
Wind storms can cause a lot of damage and suffering.
Mike Bartlett and a research team at the University of Western Ontario are out to reduce the impacts.

Neatly dressed, with a carefully trimmed moustache, Dr. Mike Bartlett doesn’t resemble any kind of big bad wolf. But he does have dark designs on a certain brick house near London.

Succinctly put, Dr. Bartlett wants to blow it down. Piece by piece, again and again. “The team is confident,” he says without a trace of malice, “that the first major damage will be tearing the roof off the second-storey wall. It’s an obvious weak spot.”

The house in question is part of the “Three Little Pigs” project, a University of Western Ontario research initiative to test the effects of extreme wind conditions on light frame housing.

At the core of the project facility—funded in part by the Ontario Innovation Trust—is a conventional two-storey home. The house is surrounded on all sides by a cage of heavy steel girders, anchored in a metre-thick slab of reinforced concrete. Mounted on this steel “reaction frame” is the project’s most singular feature: a set of 100 air cells that press against the walls and roof. The cells are connected to actuators that operate like powerful vacuum cleaners to vary pressures over relatively small surface areas and up to seven times a second, simulating uneven patterns of turbulence than can tear off a roof.

The test house and reaction frame are all enclosed in a large steel building that can be rolled back on rails, exposing the house to precipitation. Sensors in the walls will allow other members of the research team to conduct research on how moisture penetrates building envelopes and forms mould.

Despite its whimsical name, the facility will address some very pressing real-world issues. The U.S. government estimates, for example, that 1.2 million homes were damaged by wind during the 2005 hurricane season that included Katrina—and that 90,000 of those homes sustained major damage or were destroyed. The cost of this kind of devastation, both in human suffering and dollars, is enormous. Researchers at the Three Little Pigs facility hope to help reduce those impacts not only by destructive testing, but also by developing new approaches to design and construction—insights they’ll make available to industry across North America and around the world.

“We’re trying to figure out how to share our work more broadly,” says Dr. Bartlett. “We think things like web sites and video would help. Imagine a building inspector pulling out a laptop on site and showing a contractor what’s going to happen if something isn’t built right.”

It certainly beats a visit from the big bad wolf.

Project: The “Three Little Pigs” Project: Testing Full-Scale Houses and Light-frame Buildings to Destruction using Realistic, Extreme Environmental Loads
Institution: University of Western Ontario
Research Sector: Engineering
Principal Investigator: Michael Bartlett
Trust Investment: $1,891,303
CFI Investment: $2,744,599
ORF Investment: $853,296
Total research investment from all sources: $6,861,496

 

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