| 摘要 |
PURPOSE: To carry out the excavation smoothly, by simplifying the structure of a tunnel excavator with an elliptical cross section, and reducing the friction force generated between a holding member which receives an excavation reaction in the tunnel peripheral direction, and a pit wall. CONSTITUTION: At the front part of a main frame 1, a cutter head 3 is held by inclining a specific angle to the vertical surface. And, to the main frame 1, a roof support 5 is provided at the position corresponding to the excavation reaction in the tunnel peripheral direction generated by the rotation of the cutter head 3. Furthermore, a pressing device 21 to press the roof support 5 to the cutter head 3 side against the excavation reaction is also provided. |
