Centroplex adds exhibition hall

Pre-assembled truss spans lifted to support exhibition hall roof

By Sam Barnes

The most critical component of the 205,000-sq.-ft. exhibition hall and plaza at the Baton Rouge Centroplex will be completed this summer, when the last of 16 steel truss spans are placed as support for the new exhibition hall roof.

Steel fabricator Steel Service Corp. and erector Bracken Construction Co. Inc., both of Jackson, Miss., fabricated and placed the steel trusses, which reach as long as 210 ft.

The $30 million project, to be completed by January 2005, is being built by Carothers Construction Inc., Water Valley, Miss., and designed by Post Architects/Washer Hill & Lipscomb of Baton Rouge.

Darryl Ballard, project manager with Steel Service Corp., said more than 1,800 tons of steel are going into the trusses.

"An assembly area for the trusses was virtually nonexistent," Ballard added. "We had to haul them to the site in sections averaging 40 to 60 ft. long and 18 ft. wide." To prevent unforeseen problems at the site, the Steel Service Corp. crew completely assembled the steel trusses at the fabrication shop, then disassembled them for shipment.

"It's a required specification, because in a structure of this size and complexity, you're dealing with two different worlds," Ballard added. "There is the math world and the real world. There are a lot of things that can go wrong that don't necessarily show up on paper."

Once the steel arrived at the site, Bracken placed the truss sections on the ground in the approximate location of where they were to be installed. Workers then completely assembled each truss.

Three to five cranes were used to lift, place and bolt down each assembled truss section on top of 43-ft.-tall concrete columns. The entire process took three to four days.

"Under ideal conditions, we could erect about two trusses a week, but with the inclement weather we've been lucky to average just one," Ballard said. During such a delicate operation, either rain or wind can create an unsafe environment for a steel erector.

"If we're not careful, we could have a disaster on our hands. We don't want the wind grabbing the truss when we're trying to lift it." The steel trusses over the exhibition hall are painted white because they will be exposed within the hall.

Gary Lambert, project manager with Carothers Construction, said the discovery of numerous unexpected underground obstructions threw a "monkey wrench" into the project's critical path from the beginning.

"There was every kind of underground obstruction you could think of," he said. "We've hit old parts of a railroad track foundation, building foundations and numerous underground storage tanks.

"The storage tanks were totally unexpected."

When Carothers workers discovered each tank, they immediately notified the city, which dispatched environmental contractors to remove it and remediate the area.

"There were five different times that we had to go through that process, the first in October and the last in late April," Lambert said. When the unavoidable delays occurred, some quick thinking was necessary to rearrange the schedule so that work could continue. Ultimately, about two weeks of time was lost.

Lambert said other early work included driving precast concrete piles for foundation, demolishing surrounding facilities for expansions and tie-ins, and relocating utilities.

Demolition required the use of high pressure water to expose reinforcing steel at the Centroplex's existing plaza level to allow connections to the new facility.

"We had to hydroblast the concrete away to expose all of the reinforcing steel for the slabs and columns to tie into the existing structures," he added. The hydroblasting process proved faster and less damaging to the rebar.

By leaving an existing parking lot in place, the crew was able to use it as a "working slab" during the driving of 320 precast concrete piles as the foundation for the exhibition hall. The parking lot will be completely removed once the exhibition hall roof is completed and overhead work has been done.

The 14-in.-sq., 130-ft.-long spliced piles were supplied by Boykin Bros. Inc. of Baton Rouge and driven by Kostmayer Construction Inc. of Metairie.

"The underground obstructions delayed the pile driving quite a bit," Lambert said. "We met with the architect and the owner and decided it would be best if we performed some pre-excavation ahead of the pile driver to detect the obstructions ahead of time."

Anywhere from one to 10 piles were driven for each pile cap, which provide support for the exhibition hall's perimeter columns.

Lambert said project sequencing has presented another logistical dilemma for the contractor.

"Originally, we had 19 phases on this job," he added. "We simplified that by combining operations and rearranging the schedule to shave it down to seven phases."

Much of the sequencing is necessary during concrete placement for the building's floor slabs.

"There's one section near the Centroplex at the plaza level where the trusses are cantilevered, and when the trusses from the exhibition hall tie into it, it will raise the cantilevered section by about 3.5 in.," Lambert said. "We've had to sequence our concrete pours accordingly."

Project sequencing was also necessary to accommodate existing Centroplex operations.

"We're revamping the existing concessions areas, and adding new concessions and ticket booth facilities, so all those things had to be coordinated with the Centroplex," Lambert added. "The phases were arranged around their schedule and their seasons so the disruptions could be minimized."

Once steel erection has been completed this summer, Roof Technologies Inc. of Harvey will begin installing a standing seam metal and modified bitumen roof system. Beginning at about the same time, an extensive mechanical phase will require the installation of a new chiller within the Centroplex's existing central plant and the installation of a significant amount of ductwork.

Inside the building, architectural concrete blocks will go up 14 ft. in the exhibit hall area as the primary wall finish, whilie the entry lobby will be glassed in.

Lambert said the new structure will have an exterior architectrural precast concrete and stucco finish, although the south wall will have a brick finish. In the northwest corner of the building, a large overhead door will allow tractor-trailers to drive directly onto the exhibit hall floor.

Lisa Nice, project architect with Post Architects, said the building's entranceway will be particularly impressive, supported by a concrete column and beam system instead of steel trusses.

She added that each beam requires 60,000 lbs. of concrete.

"It (the entrance lobby) will basically be a tall open space," Nice said. "The lobby will be carpeted, but there will also be some terrazzo and granite interspersed throughout.

"At the plaza level, there will be meeting rooms and a nice public area. It physically connects to the existing facility, so you'll be able to walk out of this building straight into the existing Centroplex." Three meeting rooms in the plaza area measure 60 ft. by 50 ft., 54 ft. by 50 ft. and 60 ft. by 120 ft., and can each be subdivided to create smaller meeting spaces.

The largest meeting room overlooks the exhibition hall through a glass wall.

When the new exhibition hall and plaze level opens, the Centroplex will have the luxury of having its first client already under contract. A professional bowling organization recently agreed to sponsor its annual tournaments in the facility from January to July.