| 摘要 |
PURPOSE: To equalize the quality of lining concrete by compressing the lining concrete by a press jack and adjusting the shield jack pressure in advancing the rear barrel part according to the advancing resistance of the rear barrel part. CONSTITUTION: A plurality of jacks are so installed that a middle-bent jack 28 is provided between an external cylinder 12a of a middle barrel part of a shield machine having a skin plate divided into three stages and capable of constructing a curved line and a front barrel part 10, a shield jack 30 is provided between the external cylinder 12a and the rear barrel part 14, and a press jack 34 and a reaction transmitting jack 36 are provided in the rear barrel part 14 in the circumferential direction at some intervals apart from each other. This machine is so constituted that, in excavating a curved line by the machine, the jack pressure of the shield jack 30 is controlled corresponding to the advancing resistance of the rear barrel part 14 by a hydraulic control circuit so that the compression pressure of the lining concrete 50 applied via the press jack 34 can be held at constant. |
