The contractor’s crews have been accessing the Vermont Abutment off of Vermont Route 142 and will continue to access this location next week. No traffic impacts are anticipated, but motorists are advised to watch for vehicles, including concrete trucks, entering and exiting the construction site.
Delivery of steel girders to Pier 1 is scheduled for Tuesday through Thursday, April 9th, 10th, and 11th, and Monday, April 15th.
Work has continued on the cap for Pier 1 with the rebar being flown into place and tied atop the stem. Form work for the cap will be completed, bearing seats fully constructed, detail work finished, and everything fully adjusted to match plan location and elevation prior to the scheduled concrete placement next Tuesday.
Additional crews may begin work on the drainage installation required in the Barrows and Fisher yard late next week.
Crews have stripped all forms for the Pier 1 footing and stem. The footing has now been backfilled with clean stone and the cofferdam sheets have been pulled. Work has begun on the cap for Pier 1 and forms are being placed. Next Tuesday, the cap rebar will be placed on top of the stem and the remainder of the week will be spent tying the cap to the stem, installing formwork, and making final adjustments to be ready for concrete. Another crew may begin work on drainage installation required in the Barrows and Fisher yard next week as well.
The placement of 105 CY of concrete for the Pier 1 stem was accomplished efficiently yesterday and is now in its cure period. Crews are continuing work on the Pier 1 cap and will begin stripping the footing forms and conducting clean up of the Barrows and Fisher site. An additional crew is back at the VT Abutment site to make improvements to the bearing seats prior to structural steel placement. The pedestals will need to be brought up in elevation approximately 1.5″ so they will be chipped out and re-cast cleanly.
Next week, if early strength tests are adequate, work will begin on placing the Pier 1 cap steel and forms atop the stem, stripping stem formwork, possibly backfilling the footing, and removing the cofferdam sheets.
Recent favorable weather has helped the cure of the footing at Pier 1 and the strength of the concrete has allowed crews to move forward with the work on the Pier 1 stem and cap. As the stem rebar is placed and tied, form walls and corners will be set. Once the stem rebar is complete, crews will finish the cap rebar. The next concrete placement will be for the Pier 1 stem and is scheduled for Wednesday, March 6th.
Pier 1’s footing concrete was placed successfully this past Tuesday – all 220+ cubic yards of it. The contractor is waiting for the concrete to cure and achieve strength sufficient to begin work on the stem which could be as early as tomorrow and will progress into next week and the week after. In the meantime, care is being taken to keep the concrete hydrated and at an optimal temperature.
The Pier 1 cofferdam continues to have manageable groundwater flows and keeping it de-watered has been a non-issue. The formwork for the footing is mostly complete with the final bracing being finished in preparation for concrete. The footing rebar is in place and almost completely tied and the crews will move on to working on the stem and cap rebar. This work will continue into next week. Formwork will also progress on the stem and cap into next week. Concrete placement for the footing is still scheduled for Tuesday, February 20th.
The Pier 1 cofferdam has maintained a de-watered state with manageable flows. The pipe piles have been cut to grade with steel reinforcement and concrete placed. The top of the concrete tremie is currently being cleaned to prepare for footing forms and rebar. Forms should begin to be placed today and tomorrow with rebar placed and tied beginning next week. Welding of studs is expected to be complete by this week’s end. The first concrete placement for the footing is scheduled for Tuesday, February 20th.
Additional steel deliveries to the Pier 1 site in Vermont will be scheduled at a later date. Details will follow once available.
The delivery route will be along New Hampshire and Vermont Route 119 to Depot Street. This impact will include a short duration closure (approximately 10 minutes) of the twin bridges beginning at the intersection of Bridge Street to Canal Street, Main Street, and Vermont Route 142. Uniformed Traffic Officers will be located at the intersection’s entrance to Bridge Street during the closure period. While a time has not been set, all deliveries to Vermont will be off peak hours.
The recent weather has stalled steel delivery to the site, and the advance of structural steel across Pier 2 to the temporary shoring towers has been placed on hold until deliveries resume.
De-watering at the Pier 1 cofferdam continues to face ongoing challenges. The amount of water coming into the cofferdam is still too high a volume for the water treatment systems and the environmental permits. The contractor and engineering teams are analyzing the current systems in place to receive the site discharge as well as the configuration of the cofferdam to see what can be done to remedy this situation and continue with the work.
De-watering operation on hold pending further analysis.
The contractor has begun to advance structural steel across Pier 2 to the temporary shoring towers. This work will continue into next week. De-watering at Pier 1 site encountered several challenges last week and additional work has taken place to remediate the situation this week. The saturated conditions of the site and soil conditions have necessitated that the cofferdam be tighter in order to allow less water infiltration so the de-watering system will not be overwhelmed by the volume. The contractor has installed vertical forms at all four corners of the cofferdam and anticipates placing concrete today in order to achieve a better seal. The contractor will attempt de-watering again next week once the concrete has set up. Once a dry excavation can be maintained, the contractor will begin to install the 80 foot rebar cages in the 9 pier piles which may begin as early as next week. Footing formwork and re-bar installation may begin next week as well, overlapping with the pile operations.
The contractor has begun to advance structural steel across Pier 2 to the temporary shoring towers. This work will continue into next week. De-watering at Pier 1 site has begun. Once a dry excavation can be maintained, the contractor will begin to install the 80 foot rebar cages in the 9 pier piles. This could begin as early as tomorrow and be completed in time for a concrete placement for the piles as early as next week. The footing formwork and re-bar installation should begin next week as well. This operation can be conducted in tandem with the pile work.
The construction of the temporary shoring tower between Piers 1 and 2 has been completed. The contractor will begin to advance structural steel over Pier 2 and to the shoring towers over the coming weeks. Additional measures to excavate were found to be required in the cofferdam prior to the placement of the concrete tremie seal and those measures were completed this week. The placement of concrete was rescheduled for today. The de-watering and subsequent operations of cutting piles and placing rebar cages have been rescheduled with the de-watering slated to begin middle/end of next week.
The Pier 1 cofferdam has been installed. The construction of the temporary shoring tower between Piers 1 and 2 will continue over the course of next week. The de-watering and water treatment system is up and running, however, the volume of water has exceeded the capacity of the system. Additional measures to excavate and then place a concrete tremie seal in the cofferdam are being completed – hopefully by tomorrow – which should allow the successful de-watering of the cofferdam to begin next week. If de-watering can be accomplished by next week, crews will begin to work on cutting the piles to elevation and placing rebar cages in anticipation of concrete.
Pipe pile clean out has been completed and the crew is mobilizing the equipment for that operation offsite. The construction of the temporary shoring tower between Piers 1 and 2 will continue over the course of next week. Work on the Pier 1 cofferdam sheets began earlier this week and should be completed in the next few working days. De-watering and excavation to subgrade are both operations that are scheduled into next week.
Crews will continue to clean out the pipe piles into early next week. Site work for the shoring tower along the riverbank near Pier 1 has begun and will continue. The shoring tower will be a temporary means to support the structural steel while Pier 1 is being constructed. The Pier 1 cofferdam is also scheduled for construction to begin next week along with the water filtration system of tanks that will be used to treat the groundwater at Pier 1 once the excavation has concluded and dewatering can begin. The soil and the groundwater at this location will both need to be managed and mitigated due to known contaminants in the old fuel yard.
The diesel hammer has finished driving the last pile to bedrock at the Pier 1 location, reducing the noise from the site. Crews have arrived to clean out the piles and remove the spoils from the top 90 feet before the footing can be placed. This clean out operation will continue into next week. Also scheduled for next week, crews will begin construction of the temporary support system for the steel girders that will span from abutment to abutment in the Barrows and Fisher yard near Pier 1.
Due to equipment issues that have since been resolved, pile driving operations are projected to be completed no later than Monday of next week. Once finished, a crew will be onsite to begin cleaning out the piles. This operation will begin next week before the site shuts down for the Thanksgiving Holiday period.
Crews are making good progress driving the 30″ diameter steel pipes to bedrock to serve as the foundation of Pier 1. Nine are to be driven, and it is hoped they will be completed this week. If not, it will continue until completion next week.
Because of the noise, pile driving is only authorized from 7 a.m. to 7 p.m. Monday through Saturday. Once the ninth pile for Pier 1 is driven to bedrock there will be no more pile driving for this project.
The pile driving frames and platform will be removed next week, and preparations will begin for the arrival of a drill rig the following week. The drill rig will clean out the top 80 feet of each pile so they can be reinforced with concrete and reinforcing steel (rebar).
Crews have finished driving the first of nine 30″ diameter steel pipes to bedrock to serve as the foundation of Pier 1. The distance to bedrock was 150+/- feet.
Pile driving is very loud, so it is only authorized from 7 a.m. to 7 p.m. Monday through Saturday. It is anticipated to continue through Thanksgiving week. This is the last of the foundation work for this project
