| 摘要 |
PROBLEM TO BE SOLVED: To suddenly perform rotation more than a conventional method using eccentricity of a jack by independently controlling the rotational direction and rotating speed of cutters, generating rolling in a shield machine, or correcting the rolling. SOLUTION: A tunnel having a complicated cross section is formed by using a shield machine 1 having at least two cutters. In a shield machine having two circular cross sections, the two cutters 2 are constituted in a spoke shape, and are controlled so as not to mesh with each other while existing on the same plane. At ordinary excavation time, excavating resistance of one cutter 2 becomes high, and since resistance force such as stopping the cutters 2 acts on the shield machine 1, force to inversely rotate the shield machine 1 acts, and the shield machine 1 performs rolling. In this way, the rolling direction can be controlled by slide control of the cutters 2. |
