The project plans originally called for a proposed cart system to deliver the panels, but the contractor decided it could put a crane on a barge in the lake and set the precast deck panels that way instead.(VTrans photo)
Contractors on a Vermont bridge project are on track to meet the first deadline of a tightly scheduled two-phase job.
The North Hero BF 028‐1(30) Bridge 5 project involves replacing the existing bridge concrete deck, which is structurally deficient, with a new bridge deck that meets current design standards.
"The tight timeline is probably the single most challenging aspect of the project," said Vermont Agency of Transportation (VTrans) resident engineer Phillip Harrington. "Doing a project in two phases like this always takes a little longer as some tasks have to be completed twice, but it also saves overall project time by not having to put in a temporary bridge or having to deal with the challenges of a road closure."
Constructed in 1954, the North Hero bridge crosses the Alburgh Passage on U.S. Route 2. It is a seven-span, cast‐in‐place deck on steel plate girders, stretching 826 ft. long and 35 ft. wide with a curb‐to‐curb width of 30 ft. A scoping report completed in 2017 revealed the deck to be in poor condition, the two-girder fracture critical superstructure in fair condition and the substructure in satisfactory condition, based on the most recent inspection. VTrans considered three options for replacing the bridge.
In a June 2016 engineering study, several alternatives for rehabilitating the bridge were outlined. The study assessed the proposed design criteria for the bridge, impacts to right‐of‐way, wildlife, hydraulics, historic and archeological resources, as well as the needs of the local community, according to a VTrans fact sheet.
The report noted that the bridge, which saw an average daily traffic count of 2,000 in 2017, has been considered in less than fair condition since 2009, largely due to the continuing deterioration to the deck surface. The alternatives included taking no action, replacing the deck, replacing the superstructure, a full bridge replacement on‐alignment and a full bridge replacement on the old alignment. Citing site constraints and the current condition, the agency opted to replace the concrete deck along with minor steel superstructure repairs, completing the work in phased construction.
The project plan was completed in January 2021, however, due to funding availability, the contract was not put out for bid until March 2022. It was awarded to Kubricky Construction Corp. based out of Wilton, N.Y.
According to VTrans, "The new deck will be supported by the existing steel superstructure and existing substructure. The proposed bridge rehabilitation will require minimal approach roadway work and the vertical curve on the bridge shall remain the same to maintain the existing channel opening in the main span."
The bridge rehabilitation has gone as planned, with one significant change, Harrington said.
"The project is using an AccelBridge deck panel system. The project plans originally called for a proposed cart system to deliver the panels, but the contractor decided they could put a crane on a barge in the lake and set the precast deck panels that way instead, which has seemed to save a lot of time."
Since April, when crews began removing the bridge rail, curb and deck, traffic on the bridge has been restricted to one lane, managed by traffic signals at either end. Weeks after the demolition of the old deck began, work on the new deck was under way, the barge-mounted crane in place to deliver the deck panels.
Recently, crews worked from a barge-mounted manlift to build curbs on the north side of the bridge, first installing anchor bolts for the bridge guardrail, following with reinforcing steel and lastly, wood forms to the create the vertical faces of the curb.
When completed, the new bridge will have two 11‐ft. lanes and two 5‐ft. shoulders to meet Vermont State Design Standards and accommodate pedestrians and bicyclists. Phase one of the project is scheduled for completion by July. Phase two, by Nov. 2, 2023, with the final completion date for the project set for May 31, 2024. CEG
Today's top stories
