Monday, October 20, 2008

October 18, 2008 - A Big Hole

92nd, NW corner - looking S
Finally, after 15 months of hard work, we see the start of the "big hole" (in 2nd Avenue) that will become the launch box for the Tunnel Boring Machine.

Workers began digging out the hole, and decking over 2nd Avenue, about two week ago. They will continue decking over 2nd Avenue, moving up the west side of the avenue - and then they will repeat the process on the east side.

Here workers can be seen positioning new sections of concrete decking. The decking is supported by a grid of steel beams.

Another view of the decking.

92nd - looking SW
Workers have completed decking over 2nd Avenue at this location, except for one section.

Here's another view of the same access hole at this location. Obviously this hole will need to be closed before traffic is shifted back to the west side of the avenue...

What I find interesting is that the decking was installed before large quantities of earth underneath was removed. My guess is that they will completely deck over most of 2nd Avenue and only then will they excavate the hole to it's full depth of 70 or so feet. (Note: A reader just left a comment that appears to explain why they need to do more work before digging the launch box any deeper. You can click on the comment at the end of this posting.)

btw. 92nd and 93rd, W side - looking N
Here's picture of a set of the large pipes that are used to drill out the secant piles.

Here we have an typical New York City apartment building (on the east side of the avenue) framed by two of the drilling pipes.

Here you see two of the steel I-beams that form the outer edge of the launch box, with a secant pile drilling pipe in the middle. Keep in mind that these I-beams are about 77 feet in length.

btw. 94th & 95th - looking S
Here workers are positioning a new piece of the temporary pipeline that's used to transport the slurry concrete mix, from the plant on 96th street, to the job site.

Same location - looking N

This a portable screw pump for the concrete slurry. It's called a Screwsucker, and if you're really interested you can read more about this machine on this web link.

94th, near the NW corner - looking S
The worker in this picture is cleaning a piece of equipment that's sitting on top of one of the deep rectangular holes that has been dug out for a section of the slurry wall.

Same location - looking NE
This, I believe, is another one of the rectangular slurry wall holes. Workers have installed a steel rebar cage inside the hole and the next step, I believe, is to pour in the concrete slurry mixture.

I think these funny looking things are a kind of funnel that is used when concrete is poured into one of the secant hall holes. They are laying on their side at the moment.

btw. 92nd and 91st, W side - looking N
I found this large colored panel down near 91st street, in an area of the job site that is mostly used for storage at the moment. I've recently learned (from a comment that was left on the blog) that this is a welding screen. It's used to protect people walking by from the intense light and UV radiation put out by a welder.

btw. 92nd and 93rd, W side - looking S
These large blue panels are used to protect pedestrians, from flying pieces of mud, when the rotary drilling rig is working on the job site.
(This picture is sort of out of place, I know, but I thought it would go nicely after the orange panel in the previous shot. )

Here's a listing of the recent additions to the left-hand
column of The Launch Box:

Regional Plan Association:
“Tomorrow’s Transit: New Mobility for the Region’s Urban Core”
Press Release
Report (12 Mb)
"RPA Releases Transit Blueprint for Urban Core.
A new study by the Regional Plan Association lays out a comprehensive plan for new and upgraded transit for New York City and Northern New Jersey. The 53-page, in-depth report entitled “Tomorrow’s Transit: New Mobility for the Region’s Urban Core” outlines new subway, bus, commuter rail, light rail and ferry projects for the Region's ‘Urban Core,’ which includes the five boroughs of New York City and urban portions of Northern New Jersey. The nearly forty recommendations focus on providing service to underserved and impoverished areas, better connections within the existing transit network and short- and long-term transit solutions with varying price tags."

Friday, October 3, 2008

October 2, 2008

These pictures were taken on a Thursday around Noon, when the job site was very busy with activity in every block from 91st up to 96th.

btw. 91st & 92nd - looking N
In this picture, and the one that follows, you get an idea just how much equipment is now on the work site.

95th, NW corner - looking S

btw. 92nd & 93rd - looking W
Here one end of a 77 foot steel beam is slowly being lifted so that the beam can then be lowered down into into one of the secant pile holes on the west side of the avenue. (I can't imagine how much this beam must weigh.)

All traffic has now been stopped as workers prepare to position the (now vertical) beam over the hole.

btw. 93rd & 94th, SE corner - looking W
In this set of images you see a specialized clam shell bucket crane digging deep holes for the slurry walls on the west side of The Launch Box.

92nd, NW corner - looking E
The rotary drilling rig - hard at work.

95th, NW corner - looking E
Here workers are pouring fresh concrete.

btw. 72nd & 73rd, E side - looking N
Here a worker has just marked (with an orange line) the outside edge of 2nd Avenue Subway construction zone for this block. This would suggest that the MTA's contractors will be starting work in this area soon.

73rd, NW corner - looking S

And and finally, this new Second Avenue Business Association poster was spotted in numerous store front windows in the neighborhood.

- - -

Here's a listing of the recent additions to the left-hand
column of The Launch Box:

Second Avenue Business Association:
Press Release - Second Ave Retailers Issue SOS - 09/25/08

Life on Second - drawings by the artist Dominick Santise:
"The Slurry Walls" - 10/13/08
"Center Stage" - 10/02/08
"Do Not Cross!" - 10/01/08
"Digging a Ditch" - 09/25/08

Video Links:
"2nd Avenue Heartache" by Jason Rice - 08/16/08
From YouTube:
"Trailer for a short documentary on the 2nd Avenue Subway Line, know as being "the most famous thing in New York that has never been built". Finally, after 70 years of planning, construction is under way. But how are Upper east Side residents and businesses dealing with the most massive construction project in the history of the city."

The next Meeting of
The Community Board 8 Second Avenue Subway Task Force
has now been announced

Tuesday, October 28th
7:00 PM - 9:00 PM

Hunter College
129 East 79th Street
btw. Park & Lex)


1. Construction Update

a. Launch Box update

b. Shaft Site work at 69th and 72nd Streets

2. Architectural finishes and design:

a. 96th Street station

b. 86th Street station, except the entrance serving the east side of Second Avenue at 86th Street. **This entrance is being studied in an Environmental Assessment and will not be discussed at this time.

c. 69th Street entrance to 72nd Street station. **Because the entrance serving the east side of Second Avenue at 72nd Street is being studied in an Environmental Assessment, this entrance will not be discussed at this time. In addition, designs for the 72nd Street station ancillary facilities at 69th and 72nd Streets are not completed. When ancillary facility designs are complete, we will return to Community Board 8 to present them.

3. Old Business

4. New Business