When a tanker truck explosion collapsed part of an I-95 bridge June 11 in Philadelphia, PennDOT sprang into action with an aggressive plan for the crucial roadway. In just two weeks, Penn DOT and contractors C. Abbonizio and Buckley & Co. battled rain and the schedule to put a temporary roadway in place.
Dan Gleason, assistant construction engineer of Penn DOT explained the importance of this project.
"The road has an average volume of 160,000 vehicles per day, making it one of the heaviest traveled sections in the country," he said. "We were committed to getting the section that was destroyed back open so commerce and travelers could resume their lives."
This aggressive schedule meant bridge reconstruction would be impossible. Instead, project planners decided to have the debris and bridge removed and an asphalt road built where the destruction had occurred.
Cleanup in Three Days
PennDOT called on C. Abbonizio Contractors to handle the first step. The contractor, headquartered in nearby New Jersey, handled clean up in just three days. The north deck of the bridge had collapsed on the roadway, so Abbonizio cut the deck into pieces and hauled it away. Workers for the firm then cut up the other damaged sections and hauled it off site for crushing and later recycling. The heat from the original accident and the explosion was so intense that much of the material, including the rebar was pulverized.
"Abbonizio got in and got out quickly, so we could rapidly move on to the next step," said Gleason.
To get a rebuilt roadway open in record time, workers constructed three lanes, each 11-ft. wide with a shoulder. The highway will have a standard construction for the median. The traffic is being pushed to the inside, while the outside lanes are being built. The final stage will move traffic to the newly built asphalt lanes to allow sufficient room for constructing the other lanes.
"This is a temporary fix, and we are already making plans for a more permanent solution," said Gleason. "We have ordered the beams and have done the design for a new bridge, but with supply chain issues, we are not sure when we will be able to start on a new four-lane road."
The old road was just 10 years old and PennDOT plans to mimic construction of similar roads in the state.
The work for rebuilding a new road will require ordering the new beams, cleaning up the parapet walls and doing hydro demolition to remove inadequate material. Once this is complete, work crews will rebuild the back wall and pedestals. The team will then do more demolition to the remaining approach slabs before installing new dams, new bearing pads and new beams.
The next steps will include Installing the new deck with rebar. The workers will pour new concrete slab and approaches. They will then form the rebar and pour the new parapet walls and median barrier. This is all on the outside portion of the bridge. Finally, workers will restripe the lanes and open them to traffic on the new outside lanes. This work will be repeated on the inside lanes and full traffic on the new roadway will resume.
The current work required 200 tons of steel and more than 1,500 tons of reinforced concrete. The road used 15,000 cu. yds. of lightweight recycled glass aggregate. This lightweight aggregate was mainly used to reduce the dead load, since there are two storm sewers underneath the Cottman Ave. roadway.
Gleason and the project team considered many options before deciding to build a road with flexible pavements as it looked like the fastest solution.
"It will be tricky making the proper tie-ins from asphalt to the concrete roadway, but our contractor is prepared for it. That team will also be working around the leftover bridge supports, as well."
Buckley & Co.'s paving aspect of the project proceeded on schedule, using a standard 10 in. of base, 2.5 in. of binder, topped with a 1.5-in. wearing course. The temporary asphalt paving was Superpave.
Buckley crews used Gravix retaining wall system to construct firm retaining walls quickly and smoothly. The system uses cranes to position decorative precast blocks, much like a stone mason would build a traditional stone wall. The approach is in contrast to a traditional concrete pour for retaining walls.
"This is a remarkable project to get done so quickly," said Gleason. "I'm not sure that it has ever been done before in PennDOT history."
The brainpower and muscle power on the project helped make Pennsylvania Gov. Shapiro's hopes possible that he spoke at the beginning of the project.
"We have worked around the clock to get this done, and we've completed each phase safely and ahead of schedule," he said. "That's all due to the incredible coordination with our local, state and federal partners — and thanks to the hard-working men and women of the Philadelphia Building and Trades, who are making this happen." CEG
