Bob Donaldson, Post-Gazette The wheels of a truck poke through the roof of the tunnel that runs between the two sections of the David L. Lawrence Convention Center, where a portion of the floor collapsed yesterday.

By Dan Majors, Pittsburgh Post-Gazette

A 6-inch-thick section of concrete flooring in the second-floor loading dock of the David L. Lawrence Convention Center collapsed yesterday under the weight of a tractor-trailer, sending steel, debris and equipment crashing 30 feet down into a walkway and a water feature below.

	Lake Fong, Post-Gazette A high-lift vehicle and a concrete-covered beam lie in the tunnel that separates the two sections of the David L. Lawrence Convention Center after the collapse from above around 2 p.m. yesterday. Click photo for larger image. More coverage Graphic: Floor collapse at the Convention Center Convention center's problems outlined Auto show in limbo for this weekend

No one was injured in the incident, although the unidentified driver of the truck, an employee of Freeman Decorating Co., was trapped inside the truck cab for 30 minutes before rescuers could remove the windshield and pull him to safety.

"He's fine," said Mark J. Leahy, general manager for the convention center. "I understand he's a little shook up, as I can well imagine."

The 48-foot truck, which was bringing equipment for the Pittsburgh International Auto Show, was suspended across the hole, which measured 20-by-60 feet. An unoccupied high-lift vehicle, commonly called a cherry-picker, fell through the hole and was hanging twisted last night amid the debris.

Mary Conturo, executive director of the Sports & Exhibition Authority, which owns the convention center, said in a statement, "The architect, Rafael Vinoly Architects, the structural engineer, Dewhurst MacFarlane and Partners, the construction manager, Turner/PJDick/ATS, and the steel contractor, ADF Group Inc., have all been called and will be at the site [today] to assess the situation."

"We still need to get a good look at this," Mr. Leahy said. "Right now, everything on the second floor is cordoned off. It is a precarious situation.

"We have a crane company that we're talking to [about] how do we remove this [truck] or at least shore it up? But from a structural standpoint, it isn't going anywhere. It's lodged in there real good."

SEA officials said the collapse occurred at about 2 p.m. in the facility's southcentral section, where trucks were being used to remove last week's boat show and bring in equipment for the auto show.

"To have a truck in that area is commonplace," Mr. Leahy said. "The building is designed for it, is built for it. ... It was backed into the dock, being unloaded, and the floor fell out from under it."

Witnesses to the collapse described "a loud popping sound" that shook the immediate area.

Martin Cowper of Exhibit Works of Michigan said he was inside working to set up for the show when he heard a very loud crash. "It made a hell of a noise," he said.

Mr. Leahy said he was in the center's administrative offices in the northeast section of the building at the time and was unaware of the incident until he was contacted by staff members.

He said he immediately ordered the convention center evacuated in accordance with safety protocols established by the center's insurance company and the Fire Bureau. He estimated there were 150 people inside at the time, "scattered throughout the building," but the orderly evacuation was accomplished in "a matter of minutes."

Some of those evacuated were conventioneers with ECRM, a company dealing in health and beauty aids and cosmetics for drug store chains. Most of them returned to the Westin Convention Center hotel, where they were staying.

The Westin also provided a room that convention center officials used as a command center for contacting inspectors, engineers and consultants who will be involved in the evaluation.

Some staff members sought shelter from the brutal cold in the nearby Senator John Heinz Pittsburgh Regional History Center.

It was more than 2 ¹/₂ hours before fire officials and state inspectors gave the all-clear, permitting people back into the center.

"One of the first things we checked was to make sure there were no electrical, gas or plumbing lines [involved]," Mr. Leahy said. "There wasn't anything, just some cabling."

He said he could not predict what would happen with the auto show pending today's evaluation of the damage, but other functions at the convention center will go on as scheduled.

"We are able to continue activities, but it is modified," he said. "The third floor is fine. There are activities on that second floor that we cannot do.

"We don't want to cross that line where the slab fell through. We will not go across that line with any equipment whatsoever until we get an all-clear, hopefully [today]."

But the section of 10th Street that runs through the center between French Street and Fort Duquesne Boulevard will remain closed.

Mr. Leahy, who has been with the center since February 2002 and oversaw its grand opening in 2003, said he is convinced the center is safe and has no reservations about keeping it open.

"I don't know how this happened. We have no idea at this moment," he said. "The building is just tremendous. I'm proud, confident, and I feel secure working in this convention center. I have no issues with construction, none whatsoever. I've never thought twice about the safety."

Warren Butler of Chicago, who is in town for the ECRM convention, said he was outside having a cigarette with friends when he heard the "huge pop."

"We were putting out our cigarettes and going up in the elevator and as soon as the elevator doors opened, we see some people with our association coming toward us telling us to 'Go, just go for right now.' We were among the first people out."

As far as the rest of the convention is concerned, Mr. Butler said, "Everything is back to normal and the organization is rescheduling appointments that we missed. It was an obstruction to the day, but life goes on, right?"

Convention center officials said the facility's garage, which has about 700 spaces, will be open today, but customers will have to use the 11th Street entrance.

Bill Volker, who works with the Legion Community Federal Credit Union, Downtown, said he has parked in the convention center garage for a year and a half and has no reservations about using it today.

"I've got a monthly lease," he said. "I'm not going to pay to park somewhere else."