Patroon Island 'Boomer' Bridge Undergoes Structural Rehabilitation
Earlier this year, New York Governor Andrew Cuomo announced the early completion of rehabilitation work on the Patroon Island Bridge, which carries the I-90 over the Hudson River from Rensselaer into Albany, New York. The bridge carries an average of 70,000 motor vehicles per day, with an average of 84,000 vehicles daily using the I-90 and I-787 interchange on the western end of the bridge, which was also part of the project.
The $148 million project, which began in 2013, was one of the largest New York State Department of Transportation (NYSDOT) projects in upstate New York. It involved rehabilitating the Patroon Island Bridge along with all the ramps comprising the I-90 interchange with I-787.
The aim of the project was to extend the service life of the structures, and to meet higher seismic standards. Workers replaced the bridge decks and bearings, repaired steel, painted the bridges, and replaced and repaired the substructures of the interchange.
The project also included construction of new concrete piers to support the interchange ramps, and installation of new traffic monitoring systems. New concrete barriers were built on and between the bridges. Among measures used to speed construction, pre-cast concrete deck panels were used for the new bridge decks.
The Rise of "˜Boomer Bridges'
Originally installed in 1968, the Patroon Island Bridge was on the NYSDOT's growing list of bridges in need of attention. "The needs are mounting," said Sam Zhou, NYSDOT's Regional Director for the area.
Noting that the U.S. Interstate system passed its 50th birthday some years ago, Zhou said transportation officials are paying attention to a wave of "Boomer bridges" that are in need of rehabilitation, repair or replacement. In New York State it is estimated that 1,500 bridges will require that kind of attention over the next five years. Within the next 10 years, 3,000 bridges will need an upgrade.
Funding for the Patroon Island Bridge project came through the state's NY Works program, which focuses on improving the condition of bridges from fair condition to good condition in order to extend their service life. The program made $1.2 billion in new spending available to accelerate transportation infrastructure projects.
In order to meet commitments to New York residents under Governor Andrew Cuomo's "Drivers First" initiative, NYSDOT used a "Best Value" procurement method to bid the project. Zhou said the method allows contracting authorities to consider delivery methodology and contractor experience along with the dollar amount of the bid.
Halmar International (of Clarkstown, Rockland County) and A. Servidone-B. Anthony Construction Corp JV (of Castleton, Rensselaer County) won the contract based on their submission. Zhou notes that they were not the lowest bidder in the round, but "we got an experienced bridge builder" and a package that provided for the highest speed of construction and lowest impact to the traveling public.
Renovating the Bridge
To keep the bridge open, most work was done at night with all traffic crossed over from one side of the bridge to the other. The six-lane bridge maintained two lanes in one direction and one lane in the opposite direction throughout construction. Some single lane closures could occur during the daytime hours of 9 a.m. to 3 p.m., with weekend lane and ramp closures occurring throughout the project. All six lanes of the bridge were kept open during the morning and afternoon rush hours.
NYSDOT Engineer in Charge, John Nolan, likened the process of replacing the deck to a "1,079 piece jigsaw puzzle." There were various shapes and sizes, as well as differences in grading. The work involved removing the existing concrete decks and replacing them with new lightweight precast concrete panels. After existing deck was cut out and removed by crane, shear studs were welded to the roadbed. After the precast panels were placed, crews would pour a quick setting concrete to create a composite section. The High Early Strength product used would reach the required 2,600 pounds per square inch strength within three hours.
In addition to the three lane miles of precast concrete to be placed, work also included the replacement of 19 piers between 20 and 80 feet. "Under live traffic," Nolan noted. Additionally 13 piers were rehabilitated - nine on the bridge and four on the interchange stack.
Lifting Over the River
At its highest point, the roadway of the Patroon Island Bridge is 106 feet over the Hudson River, and towers of up to 80 feet were needed during the project. One particular challenge was the need to perform structural lifting operations on two piers located in the Hudson River.
The construction team devised a heavy structural lifting frame that was floated out by barge and assembled in place. They then jacked up the existing bridge to replace the old rocker bearings with high-capacity multi-rotational bearings.
There were multiple crews working around the clock, and it was a complex operation, with the coordination of the structural lifting operations, column replacement, bearing replacement and the panel replacement operations. Nolan credits his team of inspectors from Boswell Engineering for keeping tabs on all the activity.
Nolan said the task list also included close to 500,000 pounds of steel repairs, complete sand blasting and painting of all bridges totaling 763,000 square feet along with electrical work, drainage work, pipelining, slope protection, concrete repairs and existing column seismic retrofit.Landscaping was also completed throughout the project area, including part of the city of Albany's Corning Preserve, a waterfront park and natural habitat area, which was used as a staging area for the project.
In his announcement of the project completion, Governor Cuomo noted, "The Patroon Island Bridge is a key part of this state's transportation infrastructure, as well as an economic driver, that is depended upon by millions of New Yorkers, travelers and businesses from the Capital Region and beyond. These critical repairs will help ensure its viability for years to come."