Sunday, May 3, 2009

May 2, 2009

At the south bulkhead (near 92nd) of the TBM launch box - looking W

About ten days ago, the contractors reached a milestone of sorts -- they bolted together the first set of I-beams that span the full width of the launch box, from the east to the west side of 2nd Avenue.

These I-beams will provide the structure that supports the decking over the box.

For many people it may be hard to imagine that it's taken the contractors two years to get to this point. But unless you live or work in this neighborhood, or you're working on this project, you can't fully appreciate how much work has taken place to get the site to where it is today.

Bottom line... there are (and were) an incredible number of things under 2nd Avenue that had to be moved around, rebuilt, removed, or upgraded to make room for the the cavern that will soon become the launch box for the 2nd Avenue Subway Tunnel Boring Machine.

4/25/09 - 92nd, SE corner - looking SW

Another view, about a week later, on 5/2/09
The concrete shown forms the SE corner of the launch box.

- - -

Further north on 2nd Avenue, the contractors continue to install additional sections of secant pile wall and slurry wall panels, on the eastern edge of the launch box, as you can see in the following set of images.

btw. 92nd and 93rd - looking W
This is a near 180-degree view that was taken from the front of 1776 Second Avenue. The machine shown is used to drill the holes for the secant piles.
(It's a stitched image, so left-click on the image for the full view.)

This is one of the bits that is used for "drilling" into soil.

And these are steel casings that used to guide the drilling bits.

A very close view of one the steel casings.

These casings have been "frozen" at this location for about 2 weeks now.



In this image workers are digging the trench for a new piece of slurry wall panel. (The hole for the trench is being dug between the concrete guide walls shown in the lower right-hand corner of the image.)

Here the crane is lowering the clam bucket down into the trench, which when fully excavated will be about 90 feet deep.

The trench shown is full of a substance known as Bentonite slurry. The slurry mixture exerts hydraulic pressure against the trench walls and acts as shoring to prevent the trench from collapsing.

Here workers are testing the viscosity of slurry mixture by checking the amount of time it takes for a preset amount of the mixture to pass through a funnel.

4/26/09 - 95th - looking south
And even after 2 years of work, there are plenty of utility lines that still need to be relocated.

- - -

A couple of miscellaneous images and comments follow:

4/26/09 - 93rd street, SE corner - looking E
These green storage containers arrived on the work site a few weeks ago. They probably will be used to store the "spent" Bentonite slurry, before it is trucked away for disposal.

94th, east side of 2nd Avenue - looking S
A protective shed was erected over most of the sidewalk on the east side of 2nd Avenue, between 93rd and 94th, about a week ago. One source told me that the shed was put up after a piece of the facade fell off one of the buildings.

This sign was posted in the window of The Big Easy, a bar between 92nd and 93rd, in early March.
UPDATE - 6/6/09
The bar at this location re-opened in late May 2009.

- - -

And not to be forgotten... there is quite a bit of work taking place down in the 70s.

In the near term, the contractors are moving utility lines so that they can prepare the site for the construction of a large access shaft down down to the (yet to be dug) new subway tunnels.

btw. 72nd and 73rd, east side - looking N

69th, NE corner - looking N

70th, SE corner - looking N

A closing note:
I could imagine that some people are getting tired of the pictures of the machines, the decking, the beams, etc. - after 2 years, and 63 postings on this blog. Trust me, it's not so always easy to find new and interesting things to show, at times.

But, by the end of the year, if all goes well, most of the work will be underground. And then it starts to get really interesting.


- - -

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

"Second Avenue Subway Animation + Quick Facts"
(2:48) YouTube - 5/1/09
A short video, about the 2nd Avenue Subway, prepared by a 2nd year CUNY Hunter College student for her class "Shaping the Future of NYC."

NYSPE hears update on 2nd Ave. Subway
The New York Society of Professional Engineers (New York Chapter) gathered for a dinner meeting at Connolly’s Restaurant Tuesday (4/21/09) night to hear the latest on the Second Avenue Subway Project from William Goodrich, program executive with MTA Capital Construction and Peter Chamley, Deputy Project Managers, who is with DMJM+Harris+ARUP JV.

"If I Had a Hammer" - 4/14/09
"Just Off Second Avenue" - 4/2/09
Drawings and Commentary by the artist Dominick Santise