| 摘要 |
PROBLEM TO BE SOLVED: To safely and efficiently widen an existing tunnel by excavating the existing tunnel by an excavator, or achieving the excavation, propulsion and mucking at the same time in a tunnel widening machine. SOLUTION: A tunnel widening machine 1 comprises a tractor 2 and an excavator 3 larger in diameter than an existing tunnel. The tractor 2 comprises an expandable connecting machine 5 to connect a forward body portion which can be fixed and traveled to a rear body portion 22. The tractor 2 rotates the excavator 3, pulls and presses it against a cutting face to excavate the existing tunnel. The tractor 2 is advanced by synchronizing the fixing action of the forward body portion 21 and the rear body portion 22, with the expanding/contracting action of the connection machine 5. In addition, a mucking device 10 is provided close to a rear portion of the excavator 3. |
