To provide an excavation method with which the ground is excavated with no vibration and no noise without being affected on the quality of soil.
According to an excavation method, an excavation bucket is engaged to a casing and the casing is rotated by a casing jack, thereby excavating the ground while simultaneously rotating the excavation bucket with the casing. An engaged part is disposed on an outer peripheral surface of the excavation bucket, and an engage part to which the engaged part can be engaged is disposed on an inner peripheral surface of the casing. Further, regarding the engage part, a plurality of engage parts are provided continuously from an upper end to a lower end along with the inner peripheral surface of the casing and regarding the engaged part, a plurality of engaged parts or projections are provided on the outer peripheral surface of the excavation bucket.
SUMI KAZUMA
KURIHARA DAISUKE
Yasuo Ichikawa