June 25, 2007

Canadian firm honoured for participation in U.S. memorial

Dan O’Reilly

correspondent

Three, free-standing, 270-foot-high stainless steel arcs that commemorate the members of the United States Air Force has been recognized with a Project Outside of Ontario Award of Excellence from the Canadian Institute of Steel Construction (Ontario Region).

Designed by James Ingo Freed of Pei Cobb Freed & Partners Architects LLP, with structural design by Ove Arup & Partners, the Arlington, Virginia-based United States Air Force Memorial consists of stainless steel plates with high-strength concrete filling the lower two-thirds of each spire.

Construction started in February of 2006 and was completed in seven months, capping off years of planning by the United States Air Force Memorial Foundation. Centrex Construction LLC of Dallas was the contractor. Toronto-based Mariani Metal Fabricators Limited was the fabricator working as a subcontractor to Baltimore, Maryland-based Cianbro Corporation.

As the only Canadian firm to participate in the project, president and owner Vince Mariani says he gets a lot of questions of how and why his company was selected. “It was persistence and passion.”

The origin of the award stems from his company’s unsuccessful bid as the steel fabricator/erector for the Pentagon Memorial, which honours the victims of the Sept. 11, 2001 terrorist attacks on that building. Centrex Construction, which also built that structure, encouraged Mariani Metal to submit a bid for the Air Force Memorial.

“We were one of five prequalifed firms and the only Canadian one,” says Mariani, pointing out the prequalification process included the submission of several mocks up and samples. Later, however, he agreed to a joint venture proposal with Cianbro as the steel contractor. “I thought we would have a better chance if we formed a partnership with an American firm.”

It took 14 months for the spires to be fabricated and trucked to the site and another six months to erect the Unites States Memorial in Virginia.

Winning the contract involved a final interview with design architect James Ingo Freed and other selection committee members. Mariani remembers walking into the interview room, seeing his samples on a table and being asked by Freed — who did not know the origins of the samples — what he thought. “I can do better,” he recalls saying to the architect. Freed died in late 2005 before construction started.

When the company did receive the award, it realized right away the Memorial would be a unique challenge, he says.

“The quantity of material was enormous — one million pounds of stainless steel, 7,000 pounds of 100 per cent radiographed weld metal, covering 17,500 square feet of surface area.”

There were many complex technical and logistical issues involved in the project.

Mariani and his design team decided from the beginning to build the arcs in his fabrication plant in northwest Toronto.

Before proceeding with producing the spires, the team spent six months on research, including working with the designs using 3D modeling. “We’re one of the few fabricators in North America using CATIA 3D imaging technology and for this product, it proved invaluable.”

When it came to the actual fabrication, there were also significant challenges on the handling, lifting and finishing the spires, he adds.

That was met with a number of innovative engineering solutions, including the construction of jigs with a series of substations and the creation of a nylon sling and vacuum lifting system instead of chains to avoid steel contamination.

Other challenges included resolving several welding cylinder and gas procedures and grinding every joint without leaving the slightest mark, says Mariani.

The plant had to be thoroughly cleaned beforehand to prevent contamination from other metals and two other facilities were leased so the company could meet orders for its other customers, he says.

Over a period of 14 months, the spires were fabricated in a series of sections and then trucked to the memorial site. The actual erection of the monument took six months to complete and was followed by a dedication ceremony.

Print | Email | Comment