Tunnel machine excavation by TBM

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The TBM (Tunnel Boring Machine) is a tunnel excavating machine that excavates while crushing the rock mass by rotating the cutter head (TBM front) and pressing the roller cutter against the rock mass. In addition to being installed in the Eurotunnel for excavating the seabed of the Dover Strait, it was first introduced in 1964 in the Tohei Power Station headrace tunnel (Niihama City, Ehime Prefecture) in Japan. It was done.

The first full-scale introduction of TBM in NEXCO EAST was adopted in 1993 at the Yuta Daini Tunnel of the Akita Expressway as a test construction of the advanced widening excavation method for the tunnel, and the TBM with a diameter of 3.50 m was adopted for the advanced tunnel.

Since then, it has been widely adopted for evacuation pit excavation on the Tokai Hokuriku Road and tunnel digging for super-large cross-section tunnels in the Second Tomei and Meishin Tunnels. In the future, full-section TBM excavation for two-lane tunnels is also planned.

By excavating tunnels using TBM, we are planning to introduce more in NEXCO EAST for the purpose of improving safety and working environment by labor saving in tunnel construction and improving economic efficiency.