Slurry TBM evolution has allowed for increased control of face pressure and ground stability which correlates to increased success for shallow cover mining. This was a necessary component of the B/C Tunnel Extension performed in Queens, NY for the East Side Access Project. Through a coordinated effort, the designer, contractor, and construction management teams pushed a 6.86m (22'-6") diameter Herrenknecht slurry TBM beyond contract expectations, culminating in less than 1/2 shield diameter of cover. This paper explores the operation strategy with details regarding the surface and underground coordination, instrumentation plan, and program wide cost and schedule savings associated with its success.
展开▼
