|The excavation method of TBM is
divided into "Cutter" which uses the rolling force of a button
cutter and "Crusher" which the rolling and compressive force
of disc cutter. For the weatherd rocks and soft rocks, "Cutter" type
is used for more than 300-800kg/㎠ compressive strength and "Crusher"type
is used for more than 1000kg/㎠ compressive strength. Recently, it is developed
for "Crusher" to apply to various geological features.
Each cutter arranged and mounted on the front of cutter head uses different
mount and cutter according to the mounting location. If it is rolled
with the compressive force, tee edge of disc cutter gives vertical
force to the digging sectional When that force is bigger than the strength
of rock, it is crushed.
The disc cutter arranged and mounted precisely by the rolling of cuter
head crushes a rock from the outside. As the free surface is made on
the surface of rock in consecutive order, the drilling capability is
According to the cutter space and penetration depth, it is crushed as
aggregate status of 60-80mm width and 10-40mm thickness.