| 摘要 |
PROBLEM TO BE SOLVED: To provide a leading body for embedding a small-diameter pipe, which is for use in a thick mud method applicable to a PVC pipe having a small diameter on the order of 200 mm, contributes to stabilization of natural ground/working face in various conditions, speeding-up of execution of work, and simplification of shaft facilities, is high in efficiency of long-distance earth transportation, preferable to road opening, and high in embedding efficiency. SOLUTION: The leading body for embedding the small-diameter pipe is formed of: a leading body external cylinder which consists of a plurality of external cylinders watertightly connected together, has an earth excavator at a front surface, and has the small-diameter pipe connected to a rear edge thereof; an earth pressure regulating device which regulates the pressure of excavated fluidized earth produced by agitating excavated earth together with an additive injected thereto, by an earth pressure sensor and a pinch valve, so as to maintain a predetermined working face pressure; an earth removing device which vacuum-sucks the excavated fluidized earth via an earth removing pipe body arranged therein and extended to a rear edge of the small-diameter pipe, by a vacuum device located on the ground; and a vertical induction field generating device which has a vertical magnetic coil at an upper portion inside a sealed vertical cylindrical casing erected so as to penetrate upper and lower edges of the leading body external cylinder, and an earth removing passage connectable to the earth removing pipe that intersects a lower half portion of the magnetic coil. COPYRIGHT: (C)2008,JPO&INPIT |
