Excavation on the Tokyo Bay Aqua-line is completed by the world’s largest shield machines
During the Tokyo Bay Aqua-line construction, eight shield machines were used to excavate the underwater tunnel on the Kawasaki City side. Kawasaki manufactured three shield machines out of those, with a diameter of 14.14m – the largest class in the world. 1,200 cutter bits, made of ultra-hard alloy, excavated the earth with the cutter face fully rotating once every 2.5 minutes. Completely automated machines enabled single man operation, adopting Kawasaki’s proprietary automated system to assemble segments, or the blocks formed of reinforced concrete to be placed against the tunnel walls.