| 摘要 |
PURPOSE:To have no variation in the sectional diameter of a middle bent section and to make it possible to prevent an operation defect of a shield excavator from biting earth in the case of excavation. CONSTITUTION:In a shield excavator 10 dividing the front skin plate 12 and rear skin plate 14 through a middle bent section in a bendable manner, a groove 30 formed on the peripheral surface between both skin plates 12 and 14 in the middle bent section is placed to the outside thereof. A protection board 32 covering the groove 30 mentioned above is provided by fixing one end to the front skin plate 12 side. |
