ON THIS DAY: February 12, 2002, Ironworker killed by falling truss at Convention Center

PITTSBURGH — The David L. Lawrence Convention Center was built in three phases between 2000 and 2003. Just before the first phase was scheduled to open, a massive truss weighing 165 tons fell, killing one worker and injuring two others on Feb. 12, 2002.

Ironworker Paul Corsi, Jr., 37, was killed by the falling truss. He had been employed by Dick Corp since the prior summer.

The fallen truss was part of the third phase of the project. It was the 13th of 15 trusses that run north to south and support the sloping cable-stayed roof of the building.

Corsi was working on the truss, wearing a safety harness, when it fell at about 3 p.m. Another ironworker, Donald Lenigan, was working on the 12th truss as they worked together to attach horizontal floor beams. Lenigan was saved by his harness and left dangling with another worker, Walter Pasewicz, more than 100 feet above the ground, but Corsi fell with the 13th truss.

Improper bolts that were insufficiently tightened, were ultimately determined to be the cause of the collapse. The bolts sheared off as the truss tipped toward the river. Corsi was crushed underneath the truss when it pulled away from the rest of the Convention Center and collapsed.

Allegheny Coroner Cyril Wecht had recommended that homicide charges be filed against Dick Corp., which was building the center, but District Attorney Stephen Zappala did not believe there was enough evidence.

Zappala conceded there was negligence on the part of many involved, but that ultimately the proper screws and nuts were at the site and not used by the crew. Dick Corp and ADF International Inc. were both cited and fined by the Occupation Safety and Health Administration.

Another collapse in 2007 dropped sections of the concrete floor onto 10th Street, along with a high-lift, and left a truck dangling in the gap. That failure was ultimately blamed on a compromised expansion joint that seized and stressed adjoining welds already weakened by the cold weather.

Engineers investigated the entire design of the building and determined that all structural connections throughout the building needed to be retrofitted with improved connectors. When it was built, precast concrete sections were supported by steel beams, with the ends of each beam connected to a support member with bolted web clip angles, which failed in the collapsed section.

The repairs consisted of 1-square-foot steel seats with Teflon pads, a structural element that was on early blueprints for the building, but never installed.

The Sports & Exhibition Authority settled claims over the floor collapse with steel fabricator ADF Group, Rafael Vinoly Architects and Dick Corp. for $4.78 million in 2009.