Pulaski Skyway, New Jersey, USA - Joint Fill

Infrastructure rehabilitation is a major political issue in the USA, where estimates suggest that more than 70,000 bridges are now structurally obsolete.

This priority was anticipated by the FHWA, which has carried out tests for many years to identify the most permanent, highly durable and flexible solutions for use in rehabilitation projects whose urgency reflects the need to maintain mobility and traffic flow on a continuous basis.

With support and assistance from Ductal^® engineers, combined with the ability of the Lafarge Group to drive innovation, the FHWA has proven through testing the capabilities of Ductal® joint fill as an effective solution.

"We have been working for more than 10 years on the development and implementation of this solution," explains Dominique Corvez, Head of Ductal^® for North America.

"We conducted a significant number of trials, in partnership with the FHWA in the Lafarge and FHWA research centers, as well as on pilot project sites, in order to validate a solution that is now in place on about 100 North American bridges, including 30 which were completed in 2013 alone.

Thanks to the ongoing validation from the FHWA, many states (see map on page 13) have adopted this solution and their Departments of Transportation have contacted us with a goal to collaborate on projects built around this technology."

The Pulaski Skyway is a bridge that many will recognize instantly - as a signature backdrop to the popular television series, "The Sopranos". Named after General Casimir Pulaski, a War of Independence hero and "Father of the American Cavalry", this four-lane highway bridge is one of the major links between Jersey City and Newark, New Jersey.

More than 40 meters above the Passaic River, which it crosses with two main spans of 170 meters, the steel structure soars above the industrial suburbs of Jersey City for more than 5.5 kilometers.

Since work began in early April, the duration of this project has been a major concern to the 74,000 motorists who use it every day. "The Pulaski Skyway needs extensive restructuring work involving total replacement of the deck with precast concrete panels," adds Dominique Corvez. "Specifying Ductal^® joint fill provides the opportunity to adopt a solution whose strength and weather resistance has been validated by more than 2 million wheel load test cycles (fatigue testing). Stronger than the panels it connects, the Ductal^® joints will transform what is typically a point of weakness into a point of superior strength. This fact has persuaded the contractor responsible for the Pulaski Skyway rehabilitation works to extend the use of the solution, originally specified for just the joint fill connections between the slabs and the sheer pockets, to the connections between the deck and haunches. For these applications, Ductal^® is more cost-effective than the methyl methacrylate solution originally planned."

The solution is more economical, because it is easy to apply on-site and its estimated working life is measured in centuries.

Lafarge provides the project owner and contractor not only with the raw materials (premix, fibers and additives), but also technical support; experts who have specialized quality assurance training. "In addition to offering a range of special mixers, our commitment to quality and safety also means that our on-site experts apply strict controls to every mix, with temperature, fluidity, and other tests. This close supervision is particularly appreciated by US departments of transportation, which now demand it for every operation shown in the specification," continues Dominique Corvez.

"We are also very focused on demonstrating that the Ductal^® team of experts, who are in great demand, receive the support they need from all Lafarge teams in order to respond effectively to the challenges posed not only by this unique project, but also by the other 40 bridge rehabilitation contracts awarded this year. In anticipation of the increased demand, a select group of technicians from other Lafarge units were trained during the winter, so that they can provide on-site assistance this summer."

This project is the largest Ductal^® joint fill project to date and proves that this solution has succeeded in convincing America's bridge and road engineers - some of the most cautious in the world - of its strengths and benefits.

"By capitalizing on the many joint fill bridge projects already successfully completed (on which the FHWA has received very positive feedback), this project will deliver a new level of proof; that the technique can be duplicated for use in all types of structures, including those requiring extensive reconstruction, like the Pulaski Skyway and a former project in Syracuse, New York, where the work was completed in just 48 hours, thanks to the Ductal^® solution. In Europe Ductal^® joint fill will be used on the Hammersmith flyover project, a 50-year old arterial road bridge also undergoing rehabilitation. Used by 90,000 vehicles per day, the four-lane structure links the west part of London to the core.