TBM breakthrough landmark for London power tunnels

摘要

A caterpillar 3.55m-diameter TBM ('Evelyn') broke through on a section of the construction of London's underground electricity 'super highway' on January 7. The machine, which began boring in early 2012, broke through into a 48m-deep shaft at the north London suburb of St John's Wood, thereby completing 7.26km of its planned 19km alignment, which itself forms part of the planned 32km tunnel.