At the end of last week, I profiled the tunnel boring machine that the MTA said would soon be lowered into the launch box below Second Ave. Yesterday, we learned that the big date is sooner than we think.
The SAS TBM – whose 22-foot cutterhead is shown above – is heading for Second Ave. Over the next three weeks, according to a notice posted on the CB8 website, the TBM will be lowered into the launch box and reassembled. It will then start drilling out the Second Ave. Subway tunnels. The notice reads:
Tunnel Boring Machine delivery notice
Over the next three weeks, between April 12 – 30, 2010, we plan to deliver to the work site and start assembly of the 22-foot diameter Tunnel Boring Machine (TBM), all its associated back-up equipment, as well as the excavation material haulage system and removal equipment.
The TBM and associated back-up equipment are over 300 feet long, and consists of the TBM itself and eighteen double-deck rail cars on which the actual back-up equipment is carried. In addition, locomotives to haul material into the tunnel and rail cars for removal of excavated material will also be delivered. The total weight of the TBM itself is of the order of 485 tons, and will therefore be delivered in smaller pieces and assembled on site. Some of the individual heavier components of the TBM weigh between 60 to 125 tons. Similarly, the rail cars and back-up equipment will be delivered as individual components and installed/assembled in the Launch Box. All lowering of the TBM and back-up components will take place at the deck opening between 92nd and 91st Streets. A large crane will be located south of this deck opening to perform the lowering operations.
Due to the size of the machinery and DOT oversize load restrictions, the delivery of this equipment will need to occur at night between the hours of 11:00 pm and 6:00 am, on weekdays only. Lifting the equipment off the trucks and lowering into the launch Box will require up to three lanes of Second Avenue to be closed to traffic for two weeks (April 12 through April 23) and one lane for one week (April 26 through April 30) between the hours of 11:00 pm and 6:00 am. In addition, all lanes will be shut down during the actual pick of the equipment for safety reasons. Second Avenue will remain open to traffic during other times. Staging of the delivery trucks will be alongside the Launch Box and possibly at discrete locations north of 95th Street.
Please be advised that a safe work plan for this operation is in place. Due to the nature of this extended operation and safety precautions to be taken, the area will be lighted and some noise during its performance is unavoidable. MTACC will make every effort to minimize any impact to the community during these night-time hours.
As I mentioned on Friday, this TBM was made 30 years and was reconditioned to be “like new.” It has been put to use on four other projects, including the 63rd St. subway tunnel, and it was tested just a few weeks ago in Newark, NJ. Watch below a video of the testing, and for more on this TBM, check out coverage on The Launch Box and Upper Green Side.
Image above courtesy of MTA Capital Construction. Click it to enlarge.
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