Hydro demolition uses high-pressure water to remove deteriorated concrete, as well as asphalt and grout.
The George C. Platt Memorial bridge carrying Route 291 (Penrose Avenue) over the Schuylkill River in southwest Philadelphia may be getting old, but its current $42.7 million rehabilitation involves modern technology.
Originally known as the Penrose Avenue Bridge, the span was renamed some 30 years ago in honor of Irish-born George Crawford Platt. Platt served in the 5th U.S. Cavalry during the Civil War and was awarded a Medal of Honor for preventing the regiment’s flag from falling into enemy hands during a battle at Fairfield, near Gettysburg. At one time bronze bas-reliefs of Platt adorned each end of the bridge, but both were stolen some years ago and have not been recovered despite a reward being offered.
Overseen by the Pennsylvania Department of Transportation (PennDOT) the three-span bridge features 90 approach spans for a length of 8,780 ft. (2,676 m). Connecting south and southwest Philadelphia, it was built in the late 1940s and early 1950s and rehabilitated in the early 1980s and l990s. On average 56,000 vehicles use the bridge daily.
A 50/50 joint venture comprised of Vimas Painting Company Inc., of Lowellville, Ohio, and Hercules Painting Company Inc., of New Castle, Pa, is serving as PennDOT’s general contractor for the job.
The joint venture has been working with personnel of the PennDOT District 6 office in King of Prussia, Pa., along with a third party consulting firm, Greenman-Pedersen Inc., of Baltimore, Md, which is handling inspection of the sandblasting and painting of structural steel. The Trumbull Corporation, based in Pittsburgh, Pa., is providing project management services and inspection of the concrete and structural steel repairs, and URS Corporation of San Francisco, Calif., is the design engineering firm for the project. All are working in a partnering effort and have been attending bi-monthly progress meetings to co-ordinate all project related activities.
With a project completion date of June 2014, the 53 ft. (16 m) wide bridge will be rehabilitated and painted. Work to be carried out includes not only cleaning and painting all the structural steel above and below the bridge deck but also repairing concrete piers and structural steel and replacing expansion joints, guide rail and pedestrian railings as well as resurfacing the center truss and approach span. Funding for the job is split between federal and state sources at 80 percent and 20 percent, respectively.
To clean and paint the bridge, Vimas Painting Company is using a Super 8 ARS Blast-Vac and Recycle unit, the first manufactured by Advanced Recycling Systems and one of the largest in the world. Hercules Painting Company is using a Super 6 ARS Unit, also manufactured by ARS.
“It’s state of the art technology, which uses recyclable steel grit manufactured by Ervin Industries,” a spokesperson of the joint venture noted.
The companies are sandblasting the steel to a SSPC-#10 near white blast surface and applying a three coat system of zinc primer, epoxy intermediate and urethane finish, all manufactured by Sherwin Williams Paints.
Both companies are using 45,000 CFM dust collectors and Hercules Painting Company also has a 60,000 CFM dust collector, all equipment manufactured by ARS. Each company is utilizing 2-1,600 CFM I-R air compressors furnished by United Equipment Rentals, along with a few smaller 185CFM and 375CFM air compressors provided by Wistar Rentals.
In addition, a number of man lifts ranging from 135 to 40 ft. (41 to 12 m) furnished by Interstate Aerial Rentals are in use throughout the project for worker and inspection access.
“One of the many challenges to a project of this magnitude is to properly rig the bridge with a work platform below the steel under the structure, above the road and the traveling public as well as adjacent walls,” the spokesperson said. “We are also encapsulating all the structural steel being blasted with ’rip stop’ materials and ’air bag’ materials specially manufactured by Custom Canvas. These tarps at times have had to withstand 70 mph gusts of wind, with minimal damage to date.”
Subcontractor Clearwater Construction, based in Mercer, Pa., is performing concrete and structural steel repairs for the job, while B&K is handling removal and replacement of barrier walls. Line striping and eradication, hydrodemolition, and scarification are being carried out by subcontractors.
“We, the joint venture, would also like to acknowledge various other companies and their personnel for their co-operation and assistance in helping make this a successful project,” the Venture’s spokesperson said. “They include the Sunoco Company, Covenant Security Services, the Philadelphia Water and Police Departments, the State Highway Patrol, PECO, Protection Services Inc., ASTI Transportation Systems Inc., the Graham Company, Erie Insurance Company, Sadaka Corporation, Containment Design Inc., Jim’s Enterprises Inc., Hilti Inc., Sunbelt Rentals and the Lindy Apartments.”
The partners in the joint venture have undertaken similar projects individually. Vimas Painting Company has performed projects on several large structures, recently completing the John F. Kennedy Bridge over the Ohio River in Louisville, Ky., and the John Roebling Bridge over the Ohio River from Covington, Ky, to Cincinnati, Ohio, while Hercules Painting Company recently completed the Eugene Carter Memorial bridge (I-64) over the Kanawha River in Charleston, W. Va.
During the two-year project the four-lane bridge will be restricted to a single lane in each direction in various configurations. In May 2012, commercial trucks weighing more than 14,000 lbs. and hazardous material carriers were prohibited from using the bridge until the job is completed to avoid any possibility of accidents in the work zone. PennDOT also is providing a tow truck for a quick response should a vehicle become disabled on the bridge during its rehabilitation. For the duration of the job, the speed limit on the bridge has been reduced from 45 to 35 miles per hour.