When New Hampshire Department of Transportation inspectors found a crack in the girder on the Hudson, NH side of the Veterans Memorial Bridge last month, transportation officials had to close one lane of the bridge. The city also called in its Wright-Pierce structural engineering consultant to examine the crack and design a repair.
The design for a $38,000 repair of the crack about 30 inches long is complete, says Hudson City Engineer Elvis Dhima. The repair procedure includes cleaning, red dye penetration testing on both sides of the beam, magnetic drilling, installation of web plates on the I-beam and installation of high-strength structural bolts, according to a Wright-Pierce document.
The closure of the Veterans Bridge occurred on September 22, one day after the closure of the Queen City Bridge in Manchester, NH. Both closures followed NHDOT’s biannual routine bridge inspections. The westbound lane of the bridge will be closed for four to six weeks, officials said.
The eastbound Taylor Falls Bridge and the westbound twin Veterans Memorial Bridges carry about 37,000 vehicles a day on the road. 111 across the Merrimack River, which connects Nashua and Hudson across the Merrimack River. The twin bridges, built in 1972 and 1970, respectively, are jointly owned and maintained by Hudson and Nashua.
Engineering firm Wright-Pierce has completed design for a $38,000 repair of a 30-inch crack in an I-beam about 150 feet from a Hudson side abutment on the Hudson-Nashua Veterans Memorial Bridge..
Photo courtesy of the City of Hudson, NH
The city is also discussing the scope of work for the repair and mobilization with the contractor, ED Swett, an employee-owned Concord, NH-based general contractor and bridge construction company. The city hopes to be under contract with ED Swett by Oct. 2, Dhima says.
The crack was found just as the more than $3 million Hudson-Nashua Bridge deck rehabilitation project was nearing completion, according to Dhima. The rehabilitation project, scheduled for completion in December, has repaired the deck, lights and rails of the twin bridges.
“The job is basically a steel plate repair [of the cracked I-beam]”, using a 6-foot-long by 3-foot-3-wide plate and Dhima says. “The plate will be installed on both sides of the I-beam. The plate is much wider than the typical 12- to 18-length that is commonly used to connect two I-beams because “the crack is an odd shape, not a right 90-degree angle,” he says.
The plate will need extra length to cover both sides of the crack widely.
While the focus is now on the beams and bearings to repair the crack, Dhima says there are four additional beams stretching into Nashua. “It was a pleasant surprise to learn that the state is going to put us in a ten-year NHDOT plan to improve transportation and help us. [with the additional work] as this is an important bridge for the south, NH,” says Dhima.
The previous state transportation plan on bridges from 2016 to 2026 helped with the deck rehabilitation work. Under the ten-year plan, the state will cover 80 percent of the additional costs, while Hudson is securing a 10 percent match for the project, Dhima says. “We’ll start working on the contract once we take care of that [crack] repair,” says Dhima. “NHDOT is already planning $2.4 million for the second phase of the bridge rehabilitation, and we expect a letter from the state indicating the project, name and number, sometime later this week or next week,” says Dhima.
NH DOT did not respond to an inquiry from ENR about the 10-year plan.
Plans to repair a 30-inch-long crack in a beam found on the Hudson, NH side of the Hudson-Veterans Memorial Bridge are underway. Work to repair the crack will require three weeks in the field and about six workers.
Photo courtesy of the City of Hudson, NH
The cause of the crack is currently unknown, says Dhima. “The 56-year-old bridge has a life expectancy of 74 to 100 years, but it is showing some wear and tear.”
“We’ve been riding the wave,” says Dhima. “Everything is great and then we get to the 50-year mark and people say because you haven’t taken care of the bridge in the last 50 years, are you going to fix the bridge?”
Dhima says the city got lucky with the last round of repairs to the roof, lights and rails. “The state picked up most of the tab, and Hudson and Nashua only had to cover 10 percent each,” he says.
With roof repairs almost complete, the city plans to rehabilitate the I-beams under the new roof, Dhima says. “It just so happened that between then and now, a crack appeared,” he says. “Crack is paying off.”
