In true New York fashion, the TBM on the Second Avenue Subway broke through with a thunderous roar and to a standing ovation. The final breakthrough came yesterday morning (Thursday Sept 22, 2011), watched by scores of MTA workers and contractors excited to see the successful completion of more than 16 months of tunneling.
Sandhogs inspect their work
"We are excited," said Sandhog Chris Fitzsimmons. "This is big stuff for us. We are blessed with work in a bad economy."
The hard rock gripper TBM supplied to the project by Herrenknecht holed through into the existing Lexington Avenue-63rd Street station to complete its parallel 7,800ft (2,377m) second drive.
"When you stand above ground it is sometimes hard to see whether or not there is progress on this project," said MTA Chairman Jay Walder, who leaves next month to take up a new post with Hong Kong's rail operator. "But you come down here and see the Second Avenue subway taking shape right before your eyes. To watch it break through, which is a long-awaited event, is really wonderful, The day it opens it will carry 200,000 people. This is 50 years overdue really."
MTA awarded the initial $392 million tunnels and shafts contract to Skanska/Schiavone/Shea JV in March 2007.
The 22ft diameter TBM began the first of the two running tunnels, the 7,209ft (2,195m) west (southbound) tunnel, in May of 2010. It started from the launch box at 92nd Street and arrived at the 63rd Street station on February 4, 2011, having averaged about 41ft/day (12.5m/day). The TBM was disassembled and pulled back to 92nd Street and began its second drive in March. Averaging about 60ft/day, the TBM completed the 7,789 east (northbound) tunnel drive within six months.
Sandhogs celebrate the end of tunneling
The TBM launched in May 2010
The breakthrough marks the end of tunnel excavation on the $4.45 billion Phase 1 of the project that will extend Manhattan's Q Line from East 63rd Street to 96th Street.
TBM moves on to Indianapolis
Finish for the Second Avenue task
The TBM maybe through with Second Avenue, but it will not be retired. Over the next three weeks, it will be pulled back to East 92nd Street and partially disassembled. Then it will go back to the workshop before moving on to another job in Indiana, said Chris Confrey of the Local 14-14B of the International Union of Operating Engineers.
Shea in joint venture with Kiewit is the apparent low bidder for the 8-mile (12.9km) Deep Rock Tunnel Connector (DRTC) CSO contract in Indianapolis. The City expects to award the $180.2 million contract next month.
The TBM began life more than 30 years ago as a Robbins TBM delivered to New York in the late 1970s to excavate the MTA's 63rd Street Tunnel. It has tackled at least four additional projects since then, most recently the Fall River CSO Project in Massachusetts. The machine has been totally rebuilt and reconditioned by Herrenknecht USA and in Indianapolis it will work through hard rock at more than 250ft (76m) below the surface.
"This milestone is a tribute to the skilled contractors and trades people who work tirelessly every day to solve the complex engineering challenges involved in building the Second Avenue Subway in one of the most dense construction environments in the country," said Denise Richardson, managing director of the General Contractors Association of New York. "With this milestone, New York comes one step closer to completing a vision of the Second Avenue Subway first planned in the 1920s. We must make sure we continue to have the vision and determination to continue to build the transportation network that is so critical to New York's economy and basic mobility." Cast-in-place final lining work that began in the west tunnel in April 2011 continues, and will now begin in the east tunnel.
Elsewhere on the project, the MTA awarded the 86th Street Station contract last week to Skanska/Traylor JV. The JV's bid of nearly $301.8 million was below the Engineer's estimate of about $400 million. Schiavone/Shea/Kiewit holds the $447.2 million 72nd Street station contract and the reconstruction of the 63rd Street/Lexington Avenue station was awarded to Jaudlau in January of 2011.
"No one said building a subway beneath one of the busiest and most populated cities in the world would be easy," said State Senator Liz Krueger, "and it certainly hasn't been. But today, as we celebrate the completion of one of the project's greatest challenges, we are reminded of the enormity of this endeavor. Millions of people will eventually travel through this very tunnel and New York City will forever be changed by an active and vibrant Second Avenue subway line."
The Second Avenue Subway is expected to be in service by 2016.
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