Paying it Forward: Boh assists in recovery after Hurricane Sally sucker punches Pensacola by assisting in rebuilding the Pensacola Bridge.
When the new Eastbound spans of the Pensacola Bay Bridge suffered significant damage from Hurricane Sally in September 2020, Boh Bros. Construction saw an opportunity to help. Its experience in re-building the I-10 twin spans following Hurricane Katrina and more recently constructing the Lake Pontchartrain Causeway Bridge Safety Bays had equipped it with an incomparable set of skills.
This field experience proved crucial since much of the damage in Pensacola was unknown and the repairs required some on-the-spot thinking and an unconventional approach to construction means and methods.
The destructive and slow-moving Sally was the seventh hurricane of an extremely active 2020 season, and had unexpectedly intensified into a Category 2 status before making landfall with maximum sustained winds of 110 mph. The area near Pensacola took the brunt of the storm with widespread wind damage, storm surge flooding, and more than 20 inches of rainfall.
At the time, the eastbound span of the new Pensacola Bay Bridge, stretching between Pensacola and Gulf Breeze, was completed and in service, while the westbound remained under construction. “The storm rendered the eastbound span unusable,” says Rob Senior, Boh’s Vice President of Heavy Construction, “damaging several of the spans, trophy columns and footings.”
It was an all-too-familiar scenario for Boh. The storm had damaged numerous piles and girders and highway department leaders were scrambling for ideas. Seeing the need, the contractor reached out to the Florida Department of Transportation to offer assistance, and FDOT in turn connected them with Skanska, the bridge project’s design-build contractor.
Getting the heavily traversed span back into operation was top of mind. “There wasn’t a comprehensive assessment, initially, of what would have to be repaired,” Senior says. The Boh team participated in numerous meetings with Skanska to assist with the damage assessment process and to determine what the designers needed to be replaced and what resources would be required.
Meanwhile, FDOT performed its own assessment and coordinated closely with the team to identify what needed to be removed, repaired or re-incorporated. “Much of it involved damaged piles so there were a lot of dive inspections,” says Thad Guidry, Boh project manager. “Some spans had also shifted and girders were broken.”
An Abnormal Sequence
During a typical bridge project, the contractor drives piles, sets footings and trophy columns, places girders, and pours the deck. Once in place, the bridge isn’t designed to be de-constructed. “Once the decks are placed, you can’t simply take it apart in reverse order, so we talked to Skanska about incorporating some of the means and methods used during the Causeway Safety Bay project,” he adds.
In essence, the project team had to remove the spans, trophy columns, and footings in locations where the piles were damaged, then drive new piles – ultimately converting four piles caps into six. The Boh team worked with Mammoet to create a plan to remove the damaged span sections as a unit with SPMTs (Self-Propelled Modular Transporters), then demolish them offsite.
To expedite the work, Boh performed several operations at once, while Skanska continued its construction of the new westbound spans and overall management of the eastbound repair effort.
It evolved into a rather complex logistical effort, whereby the Boh engineering, fabrication and operations teams developed concepts for the removal effort while simultaneously sourcing materials. “The work plan details were still being developed, even as the barge setups were being fabricated, assembled and shipped.” Senior says. That necessitated a highly malleable and adaptable schedule. As new information came in, the orientation of the barges changed several times, along with the process for transloading and demolishing in place and disposing of the material.
The water-based location of Boh’s Almonaster yard proved critical. The contractor developed plans and executed any necessary fabrication in the yard. “We understood the emergency nature of this project, with double shifts at times, but we did it safely and still put out a first-class, quality product” says Vincent Rabalais, General Superintendent of the Piling and Maine group.
The bridge consists of a main bridge deck and a separate pedestrian walkway on an adjacent independent span. Some of the girders were in such bad shape—they had been struck at the midspan—that it was difficult, if not impossible, to lift them off in one piece. “So, in addition to the SPMTs we demolished some of the pieces in place using a structure fabricated in our yard and supported from a barge,” Senior says.
Boh monitored the footings and trophy columns throughout the span removal process to ensure they didn’t further damage the bridge. Any unintentional damage would have undoubtedly added more time and expense to the project and caused the bridge to be closed longer. Every crewman, in fact, had “stop work authority.” For example, a Boh foreman noticed cracks in one of the girders and called off the first removal. “He picked up the phone, called an ‘all stop’ and we changed the methodology and used the wing structure to demolish the beams in place rather than using SPMTs,” he adds.
“That goes back to the confidence we have in our crews to use stop work authority when things are not going to plan”
Vincent Saladino, who was the Construction Manager overseeing this project, says it wouldn’t have been possible without the multi-department collaboration within the Boh organization. “We always knew that there was an answer,” he adds “We were there to serve our client, Skanska, the FDOT, and the citizens that use the bridge,” he adds. “It was a collaborative process where we were focused on tackling a very difficult project as quickly as possible, and we were all pulling in the same direction.”
This article was originally published in The Boh Picture. You can read more about Boh Bro’s projects here.