Waterfront Winner-GMF Steel Group

Tampa Convention Center, Tampa, Fla.

Structural Class III ($1 Million to $2.5 Million)

Erector: GMF Steel Group

Fabricator: GMF Steel Group

Detailer: Ovation Services LLC

Structural Engineer: Walter P. Moore

Architect: Baker Barrios

Construction Mgr./GC: Skanska USA

Contract Value: $1.7 Million

Tons of Steel: 303

The expansion of the Tampa Convention Center in Tampa, Fla., added 23,500 square feet of new meeting rooms and brought the building’s total flexible space to 600,000 square feet.

When GMF won the bid to fabricate and erect steel for the expansion, it faced a number of significant challenges.

First, the convention center sits along the Hillsborough River in downtown Tampa, and the expansion added a new outer row of rooms to the second and third stories on the side that is right on the riverbank. That meant the only feasible way to do the work was from barges – something new for GMF.

Second, GMF had to finish its work in 55 days while not disrupting any of the convention center’s events.

Third, the project design called for GMF to prepare the convention center’s existing structural steel so the addition’s steel could tie in seamlessly. Part of that challenge was figuring out how to install the addition’s 32 roof beams through a concrete façade without affecting the existing roofline.

Creative Solutions

To work successfully and safely from the river, GMF contracted Beyel Brothers Crane & Rigging Inc. to provide a 220-ton capacity lattice-boom crawler crane, three large barges, tugboat services, and bargeuse advice.

“Barges were clearly the most effective solution for this job,” said GMF’s Field Operations Manager. “Other options would have disrupted convention center operations and posed unnecessary safety concerns.”

Working together, GMF and Beyel Bros. calculated that using one barge to support the crane and rotating the other two as floating laydown yards for steel would deliver the best cost and efficiency.

Each steel-carrying barge was 120 feet long, 45 feet wide, and had ample buoyant capacity to handle everything GMF needed to put on it. The barge supporting the crane was even longer.

“Based on the heights, weights, and radii of the planned lifts, GMF and Beyel Bros. chose a 220-ton capacity Manitowoc 14000 Series-2 crane with 174 feet of boom,” explained the Field Operations Manager.

The two “floating laydown yard” barges also had more than enough capacity for the steel loads. The vital part was making sure the steel in each barge load was layered onboard in the reverse order that it would be erected. That way the crane could pick each piece in sequence without having to move any others.

In all, GMF fabricated and erected 303 tons of structural steel, including 733 main pieces, along with 37,000 square feet of steel decking for the addition.

Precise Planning

According to GMF, both 3D Lift Plan and Synchro 4D scheduling software played key roles in improving efficiency, safety, and coordination on the project. Beyel Bros. used 3D Lift Plan and GMF-supplied information to develop detailed crane positioning and lifting plans that ensured each lift was safe and efficient. GMF’s use of Synchro 4D drove and coordinated the whole project, enabling the company to schedule fabrication, barge loading, and steel erection piece by piece, with a stepby-step visual sequence that it could share with the client and communicate clearly to field crews.

As one example, GMF used the program to plan each barge load digitally in 3D to make sure every piece of steel went on in the right order and fit on the barge as expected.

This comprehensive planning helped it avoid problems and prepare responses for anything that might go wrong. “We put so much forethought into the planning that everyone knew exactly what to do if a hiccup happened,” said the Field Operations Manager.

During its preconstruction planning, GMF held coordination meetings involving the Preconstruction, Detailing, Fabrication, Construction, Safety & Quality, and Project Management departments bi-weekly, weekly, and daily.

As the actual work progressed, GMF used a digital-twin model to coordinate steel erection. A digital twin is a real-time digital representation of field conditions. It updated continuously to reflect design changes, construction progress, and other on-site developments for an accurate digital snapshot of the project. According to GMF, this allowed their team to monitor progress, identify challenges early, and make informed decisions quickly.

Excellent Execution

The first step in GMF’s erection work was reinforcing the convention center’s columns where the addition would tie into the existing building.

After another subcontractor had demolished the convention center’s outer wall, GMF connected a short sister column to either side of each existing column. The sister columns would reinforce the original columns and support the addition. They also reinforced a former interior wall that was left in place temporarily to keep the building weathertight until the addition covered it.

The most complex pieces of steel to set were 32 Z-beams that tied the addition to the existing building at the top of the third floor. Each Z-beam was originally designed as three sections to be set individually and then field welded into a single piece. Seeing an opportunity to improve both efficiency and quality, GMF got the engineer of record’s approval to fabricate and install each Z-beam as a single piece.

The shape of the Z-beams and the tight workspace increased the installation complexity. Earlier in the project, the demolition crew cut a tight slot through the building’s concrete façade for each Z-beam to slide through. Those slots were barely wider than the beam, requiring precise alignment during installation.

Each Z-beam measured about 20 feet long at roof level, then had a 5-foot drop followed by 10 more feet of length. Its shape allowed it to fit under the existing cantilevered roof and tie back to the convention center’s structural columns.

With a Z-beam suspended from the crane, GMF ironworkers inserted the first 10 feet of the beam through the slot, and then tilted the leading end down to accommodate the 5-foot drop before tilting the beam back to level so its last 20 feet could go in. During the process, two ironworkers with taglines and one with a come along carefully controlled the beam.

Though installing the Z-beams that way took skill and precision, it saved many hours of field welding.

After a Z-beam had been installed a GMF crew attached it to the convention center’s existing frame. To minimize disruption to convention center operations, the tie-in work took place at night.

The efficiency of GMF’s meticulously planned and flawlessly executed steel erection process helped accelerate the whole project.

In addition to the time saved by installing the Z-beams as single pieces, GMF found that its smooth efficiency enabled it to consistently hang iron faster than the plan expected. “We were able to tell that to the general contractor, who was then able to move up the schedules for the project’s other trades,” said the Field Operations Manager. As a result, GMF helped accelerate the project’s entire schedule by about one and a half months.

Experience Pays Ongoing Dividends

Lessons learned on this project continue to pay dividends for the company and its customers. This project provided valuable lessons in advanced planning and early team engagement.

By bringing field crews in for detailed training and briefings well before mobilization, everyone was prepared to hit the ground running, which minimized inefficiencies during the start of the project.

The barges, initially seen as a potential challenge, showcased the benefits of a controlled and predictable laydown area. Clear communication with the client about space requirements for unloading and staging steel proved critical.

Using the digital model, GMF tested multiple barge-loading scenarios to determine the most efficient approach, ensuring materials were staged safely, accessible for the crane, and aligned with the overall project schedule.

According to the Field Operations Manager, the lessons learned from the intensive planning “changed the way we do business.”