Second Avenue Subway TBM Breakthrough 9/22/2011
Workers completed tunneling for the first phase of the Second Avenue Subway on Sept. 22, 2011, when the project's tunnel boring machine reached the Lexington Av-63 St station, breaking into the existing subway system. The 485-ton, 450-foot-long TBM used a 22-foot diameter cutterhead to mine 7,789 linear feet in two tunnels, averaging approximately 60 linear feet a day. Photos by Metropolitan Transportation Authority / Patrick Cashin.
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