ENGINEERS WEEK Bridge Work Done Right
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SPECIAL REPORT ENGINEERS WEEK Bridge work done right Lewiston-Queenston makeover was done quickly, efficiently and with minimal traffic disruption Business First of Buffalo - February 20, 2006 by Dale English A law of physics stating that that the lesser can never contain the greater met its match last summer when, thanks to 21st century engineering and construction techniques, a fifth traffic lane was inserted into the majestically arched Lewiston-Queenston Bridge with hardly a ripple of problem. It was done so quickly and efficiently and with such minimal traffic disruption, even during peak summer travel time, that some might be tempted to ask, "What if they rebuilt a bridge and nobody noticed?" And it was done in minimal time-11 months-through winter's cold and summer's heat, snow and wind, in daylight and gloom of night. Workers were double-shifted and for some, "Saturday Night Live" was an eight- or 10-hour date with a jackhammer on the bridge deck. 'Miserable' timetable "It was a miserable timetable," said Tom Garlock, general manager for the Niagara Falls Bridge Commission , the customer on the job costing about $45 million Canadian. Agreed, said two principals in the project, Kenneth Rawe, vice president of Oakgrove Construction Inc. , of Elma, and Bill Snow, construction engineer for Rankin Construction Inc. , of St. Catharines, Ont. Rankin was the prime contractor with Oakgrove, as its subcontractor, handling all work on the American side of the bridge. Both men are professional engineers. The problem was the Lewiston-Queenston Bridge-known as Queenston- Lewiston in Canada - simply wasn't big enough anymore to handle its daily traffic load. Opened in 1962 as the replacement for the second Lewiston-Queenston Bridge that dated to 1899, the bridge had four lanes-two in each direction-linking the villages of Lewiston, N.Y. and Queenston, Ont. A four-foot-wide median and an eight-foot-wide sidewalk were part of the original span that, as time passed, took on increasing importance as a major trading route between the two countries. They were removed to provide space for the fifth lane. Rainbow replica An arched span with twin abutments on both ends, the structure is a replica of the Rainbow Bridge farther upstream. It is 1,600 feet long from abutment to abutment, with the deck soaring about 370 feet above the Niagara River Gorge. It's owned and operated by the NFBC, an international entity that also operates the Rainbow and Whirlpool bridges in Niagara Falls. When it was completed, Lew-Queen was the longest hingeless steel arch bridge in the world. Situated as it is, linking New York's Thruway system and its I-190 tributary with Ontario's Highway 405 to the Queen Elizabeth Way and Toronto, the Lew- Queen has become the fourth largest border crossing in dollar volume between the U.S. and Canada. Traffic overload "It's handling between $25 and $30 billion worth of trade annually," Garlock observed. Traffic volume is 4.3 million vehicles annually, a million of which are trucks. Eighteen-wheelers routinely backed up for miles into Canada, awaiting clearance through U.S. Customs, causing deadly serious traffic problems as the bottlenecked vehicles jousted for bridge position with regular traffic. "Following the 9/11 tragedy, Canada and the U.S. created the FAST (Free and Secure Trade) program which allows truckers with FAST status-granted after passing extensive background checks-to clear the border quickly. But, it does no good to speed trucks through, only to have them get caught in traffic," Garlock said. The plan then, was to convert the four existing lanes into five, creating a dedicated lane for commercial vehicles with FAST status and a second one for all others. That separation extends well into Ontario, with the construction of new dedicated truck lanes along Hwy. 405, with the added benefit of separating 18-wheelers from other vehicles. "The work also involved a complete seismic retrofitting of both the arch and the abutments. That was needed to bring the bridge up to modern construction codes," Garlock explained. No American tax dollars Financing was split three ways, with the governments of Ontario and Canada each putting up a third, and the remaining $15 million coming from the NFBC. "They were trying to get their exports to the U.S. more quickly and had already spent the money on the dedicated lanes" along Hwy. 405, observed Rawe at Oakgrove. "It was the first time in our 67-year history we took public money," Garlock said, explaining that in the past, bridge funding came from NFBC's pocket and that no American taxpayer dollars were spent on the fifth lane project. "Because we were primarily using Canadian dollars we felt the job should be bid in Canada," Garlock continued. However, given the extreme complexities of labor and immigration laws in both countries when it comes to construction, it was deemed best for each side to handle its own work. Rankin Construction, Inc., a 28-year-old St. Catharines contractor heavily into highway and bridge construction - it even has its own marine division - was the low bidder and selected Oakgrove as its American partner. 'We've known Oakgrove for a number of years and we worked together on a Peace Bridge job three or four years ago, doing a lot of concrete (restoration) work on the piers and abutments" explained Rankin's Snow. "The companies complement each other well and at the time we discussed the possibility of doing a job together some time in the future," Snow continued. Those discussions rekindled before Rankin was awarded the fifth lane contract late in 2004. "We were delighted that Rankin selected Oakgrove," Garlock said, pointing out that in 2003 Oakgrove had worked on redoing the American toll plaza. "We had a good experience with them then," he added. Winter start-up Work began in December 2004 and was completed in early November 2005, several weeks ahead of schedule, despite an extremely tight time schedule. According to Rawe and Larry Zack, Oakgrove's project superintendent, the company's work involved removing and replacing the old bridge deck from the center of the arch span backwards to the east (American) side, performing steel repairs, painting, and approach work. Oakgrove's portion of the contract was worth about $15 million, U.S. The project was challenging from several aspects. Because the bridge is an international crossing and a high-profile structure, security was a big concern in the post-9/11 world. Traffic flow had to be maintained-close two lanes and work on the other side, then reverse the process-but vehicles weren't allowed to back up on the bridge. Worker safety, as well as access to the job site high above the gorge, were also critical, particularly during and after removal of the concrete decking. "We used a special platform underneath the bridge known as the Beeche QuikDeck System," Rawe explained. Produced by Beeche Systems Inc. , of Scotia, N. Y., over 90,000 square feet of specially constructed plywood panels mounted on a reinforced steel lattice grid were installed under the bridge decking. "It was a plywood deck hanging from the underside of the bridge by heavy chains, nine feet below the bridge," Rawe explained. "It was both a safety and an access platform," he added. The deck was configured so that even if one panel failed-none did-there would be no domino effect involving other panels. That allowed room for both men and materials, as well as a safeguard keeping stray chunks of concrete, for example, from cascading into the gorge below. Trickiest part Rawe noted that the trickiest part of the job was the need to remove-and replace-the bridge decking at the same rate on both the American and Canadian sides. "To remove the deck we sawed it into 7-by 10-foot slabs with diamond saws, loaded them into dump trucks with a special lifter, and removed them. But, we had to remove them at the same rate from the center so the arch didn't become unbalanced," Rawe explained. Sawing concrete in below-freezing weather initially posed a problem for Oakgrove, Rawe recalled, because diamond saws are water-cooled. "The last thing we needed was a lot of ice up there," he said. A call to Rankin solved that. They had a special de-icing agent added to the water to prevent such a dangerous eventuality, Rawe recalled. Balancing act "We had to stay within 40 feet of each other or the bridge could go out of balance and that would damage the arch, so we had to tear down and pour at the same rate," Snow added. In other words neither the American nor the Canadian crews could be more than 40 feet ahead of each other, something that generated some good-natured back-and-forth banter between each company's workers. "We started in the middle with removal and worked at a similar rate during disassembly. In rebuilding, crews started at the abutments and met in the middle," Snow noted. Pouring the new decking was at least equally complex because over 4,000 cubic yards of concrete - 1,063 of them into the arch span - had to be poured almost in unison from two directions for the bridge deck, barrier walls, approaches and related amenities. Two identical 52-meter concrete pumps from Pumpcrete Corp. of Niagara Falls, Ont., were used, with identical backup machines available if needed. (They weren't.) The vehicles' weight, set-up locations, and placement of their outriggers, had to be worked out in advance, to maintain bridge balance.