How the Sir John Carling Building will be destroyed
Ian MacLeod, Ottawa Citizen
Published on: July 9, 2014, Last Updated: July 9, 2014 7:28 PM EDT
The biggest blast in the capital’s history happens Sunday when a famed U.S. demolition team blows up the Sir John Carling Building into 40,000 tonnes of rubble.
The obsolete federal office tower overlooking Dow’s Lake is to take a spectacular plunge from the city’s skyline at 7 a.m.
Eric “master blaster” Kelly of Advance Explosives Demolition Inc. of Idaho will push a button detonating about 400 kilograms of dynamite in an intricate sequence of small, controlled explosions within the 11-storey structure.
Boom-boom-boom-boom.
In the time it takes to read this paragraph, 930 Carling Ave. should shudder and collapse into smithereens, imploding into its own footprint. By next summer, the pulverized concrete is to be covered with clay, topsoil, sod and trees. Total cost to Public Works for the “deconstruction” is $4.8 million.
People are welcome to watch – but from no closer than 300 metres. Safety is paramount, says Marc Verticchio, site supervisor for the main contractor, the AIM Environmental Group of Stoney Creek, Ont.
City and federal police, private security guards and volunteers will staff road closures and barricades.
“The implosion will not happen if someone ventures into the prohibited zone,” warns Verticchio.
Nearby residents are advised to stay indoors. Warning sirens will wail. The rest of the city shouldn’t hear or feel a thing.
Still, this job is no push over.
Concrete and steel reinforcing rods were inexpensive in 1967 when workers erected the former Agriculture and Agri-Food Canada headquarters.
“This is a heavily-reinforced building,” says Kelly, gazing up at the 40,000-square metre edifice, stripped bare of everything from wiring to asbestos. It’ll take about 2,000 high-explosive charges to knock it down in a precisely-planned feat of engineering.
The surrounding area is open Experimental Farm property, except for one critical obstacle. Just metres away, on the northwest side, sits a small, one-storey former cafeteria building known as the “West Annex.” It’s a heritage site the government wants protected.
So Kelly has to get the tower to fall to the southeast, just enough to miss demolishing it.
“This is a tough one,” says master blaster.
Kelly estimates he has “shot” close to 1,000 structures in his 35-year career. He holds world records. In 1994, he lit the fuse on 5,400 kilograms of explosives and toppled a 251,000-square-metre Sears building in Philadelphia, the largest U.S. structure ever demolished with explosives.
Things haven’t always gone as planned, but no one has ever been hurt.
“I’ve been doing this 35 years and if you find any blasting company – I don’t care if they shoot rocks, stumps or whatever – who says they didn’t have something that didn’t go the way they like, they’re liars, they haven’t been in the business long enough,” says Kelly.
At 54, he is burly and affable, with a red-meat, backwoods kind of vibe. As an 11 year old, he watched his father, a blaster in Pennsylvania’s coal mines, topple a smoke stack. He’s never looked back.
Kelly lives from hotel to hotel about 50 weeks a year with his wife and the company president, Lisa. They’re accompanied by their four young daughters, who are home-schooled by Lisa. The family returns to their 200-acre northern Idaho homestead and horses once or twice a year.
The couple also has four grown children from previous marriages, including fellow blaster Eric Jr., 32. The entire clan starred in the short-lived TLC reality TV series The Imploders.
Kelly is also an evangelical Christian pastor who wears his religion not on his sleeve, but on his construction helmet, adorned with the three crucifixes of Calvary.
“We’re not Bible thumpers,” explains Lisa. They do, however, thump the holy — out of buildings, bridges, blast furnaces, silos, sports arenas, nuclear power plants and towers around the world.
Calgary, Montreal, Miami, Greece. Boom-boom-boom-boom. Nova Scotia, Minneapolis, Toronto, West Palm Beach. Boom-boom-boom-boom.
Success comes down to God and gravity.
“On the day of the shot, we’ve done everything that we can do with the talents that God gave us, (so) it’s all up to him whether we’re going to be a hero or a bum,” says Kelly.
It’s a good omen then that old Sir John Carling will be laid to rest on a Sunday.
If the sky is clear, spectators will hear a noise as the air rushes outward, but shouldn’t feel a thing.
If there’s low cloud, more of that air blast could be deflected outward, rather than upward, like putting your hand in front of a stream of water from a garden hose.
Still, there should not be enough overpressure to break windows outside the immediate area surrounding the building.
It’s nothing like the image many have of explosives and explosions from Hollywood, wars and terrorism.
With a bomb, highly-pressurized, super-heated gases expand outward in a supersonic blast wave, cutting down everything in their path.
Explosive demolition, on the other hand, seeks to compromise the structural integrity of the building just enough to let gravity, the invisible glue that hold the universe together, do the rest.
By weakening its vertical strength, the weight of the building triggers a cascading failure of floors, like a house of cards.
Building “implosions” are a popular and efficient way to down big buildings, especially in crowded cities. Demolishing a large building floor by floor takes months. But this way, “stand back, push the button, and it’s on the ground,” says Kelly. “It’s a lot easier to process the (debris) on the ground then when it’s up in the air.”
For the past month, six to 15 AIM Environmental Group workers have been prepping the building for the big show.
The building’s 168 main vertical support columns, running from the basement to the roof, are constructed from reinforced steel rods encased in concrete.
From the first basement to the fourth floor, each column contains two bundles of rebar. From the fifth floor to the roof, each column contains one bundle.
Each bundle contains eight rods. Each rod measures about 60 millimetres in diameter, a little bigger than a golf ball.
Each bundle is also wrapped with a final piece of spiralling rebar, forming what’s called a “birdcage.”
It’s a mighty a strong cage. But simply destroying it with dynamite would require extra explosive and increase the chances of fly rock sailing in the wrong direction.
Instead, Kelly and his crew will use smaller explosive charges to bend the rebar outward so it loses its vertical strength.
Main support columns in the first basement and first and fifth floors are ground zero.
Over the past month, AIM Environmental Group workers have cut through the rebar that wraps each bundle on those three floors.
They’ve also drilled about 2,000 1.5-inch holes into the columns, four or five per column per floor, to hold the sticks of dynamite. Additional holes have been drilled in the shear wall supports encasing the elevator shafts and stairwells near the centre of the building.
(AIM has been on site since April 2013, removing and recycling the structure’s interior. It expects to exceed Public Works’ stipulation that at least 75 per cent of the building materials be recycled.)
The columns will then be wrapped with two layers of nine-gauge chain link fence, to contain or at least slow down large pieces of concrete from flying away. Then a layer of heavy-duty, 16-gauge, non-woven geotextile fabric will be wrapped around that to stop or slow down smaller pieces of fly rock.
Finally, the entire exterior length of the first and fifth floor and the above-grade portion of the first basement will be sheathed in more protective geotextile.
“The big thing is safety, safety, safety,” says Verticchio. He explains that Sunday’s blast was supposed to happen last Sunday, but he would have had to hurry his workers to complete the preparations on time.
“A blast is one of the last things you want to rush.”
On Sunday morning, he and Kelly and crew will be stationed in a command post, at an undisclosed nearby location.
“You never know, there’s crazy people out there,” says Verticchio.
Warning sirens will sound, 10 minutes, five, and then one minute before Kelly pushes a firing button starting a delayed sequence of explosions. He won’t reveal many specifics.
“We kind of keep that proprietary. If everybody knew how to blow up a building a lot more people would do it.”
The explosions will begin in the basement and travel upwards. They’ll also detonate from east to west, to “pull” the falling structure away from the West Annex.
Afterward, the Kellys will head off in their Dodge pickup to implode in Pennsylvania, Minnesota, Wyoming, Hungary and beyond. Boom-boom-boom-boom.
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