JPH0353431B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for constructing a shaft, and more particularly to a method for constructing a shaft that connects from the ground surface to an existing horizontal shaft.

(Prior art) When constructing a shaft that connects to an existing horizontal shaft as described above, retaining plates such as sheet piles are driven from the ground surface toward the existing horizontal shaft, and the ground divided by the retaining plates is excavated. A hole with a larger diameter than the planned shaft will be formed, and a shaft made of concrete pipes will be constructed within this hole.

(Problems to be solved by the invention) In the conventional method, a large diameter hole is excavated for constructing a shaft, which not only requires a large space on the ground, but also requires a large amount of soil to be excavated. In order to prevent collapse, shoring materials are required in addition to retaining plates, and in the case of soft ground, auxiliary construction methods such as chemical injection must be implemented, which lengthens the construction period and increases construction costs. There was a problem with becoming.

This invention solves the problems of the conventional method as described above, eliminates the need to excavate large diameter holes for shaft construction, and allows shafts to be constructed at any location in a short period of time and at low cost. The purpose is to provide a method.

(Means for Solving the Problems) This invention for solving the above problems connects the ground surface and an existing horizontal shaft with a plurality of cables installed vertically, and has a cutting hole at the bottom, and By applying a traction force to a cylindrical excavator body equipped with an upwardly directed earth discharge pipe using a traction means provided inside the excavator body, the excavated soil is moved to the ground surface by the earth discharge pipe towards the existing horizontal shaft. A method for constructing a shaft is characterized in that the pipe is press-fitted into the ground while being discharged, and as the pipe is press-fitted, a pipe body serving as a shaft wall is sequentially connected to the upper part of the excavator main body.

(Example) As shown in Fig. 1, 1 is an existing horizontal shaft,
A plurality of holes are drilled from the ground surface 2 toward the existing horizontal shaft 1 by auger boring or the like, and a PC steel wire 3 is inserted into the holes so that its lower end protrudes into the horizontal shaft 1. The number of PC steel wires is appropriately determined depending on the geology and the distance to the horizontal hole.

As shown in FIG. 2, a reaction wall 4 is formed inside the wall of the horizontal shaft 1, and the lower end of the PC steel wire 3 is fixed to the reaction wall 4 by a fixing device 5. The upper end is inserted into the excavator 6. As shown in FIG. 4, the excavator 6 includes a cylindrical main body 8 with a cutting edge 7 provided at the bottom, and this main body 8 is attached to a pipe such as a concrete pipe via an annular mounting plate 9 and bolts 10. 11
is fixed. A pair of upper and lower support plates 12 and 13 are fixed inside the main body 8, and a plurality of hydraulic jacks 14 for traction are provided between the plates 12 and 13.
is arranged, and the rod portion 15 of the jack 14 is fixed to the upper support plate 12. Jack 1
4 has a chuck device 16 fixedly attached thereto. PC
The steel wire 3 has a cutting edge part 7, upper and lower support plates 12, 1
3. It is inserted into each hole provided in the mounting plate 9 and the tubular body 11, and is drawn out into the interior of the tubular body 11.
And the PC steel wire 3 is the upper and lower support plates 12, 1
3, the chuck part 1 of the chuck device 16
It is designed to be held by 7. 18 is a jack for correcting the direction of the blade mouth portion 7; 19;
2 is a speedometer that measures the excavation speed from the rotational speed of a roller that rotates in sliding contact with the PC steel wire 3; 20 is an earth removal pipe for discharging earth and sand taken in by an earth removal device (not shown); 21 is an earth pressure or water pressure gauge, 22
A target device is irradiated with a laser beam 23 to measure the position of the excavator 6, and 24 is an inclinometer.

To press the excavator 6 into the ground, extend the rod portion 15 of the traction jack 14 and close the chuck portion 17 of the chuck device 16 as shown in the fourth figure.
When the PC steel wire 3 is grasped and the rod portion 15 is retracted in this state, a traction force is applied to the PC steel wire 3 as shown in Figure 5, whereby the main body 8 is press-fitted into the ground. After press-fitting the main body 8 by the stroke length of the jack 14, open the chuck part 17 and insert the PC steel wire 3.
Release the grip and extend the rod portion 15 of the jack 14 to the state shown in FIG. 4 again, and repeat the same operations as described above. Excavated soil during press-in is discharged to a dump truck 25 or the like on the ground via an earth discharge pipe 20.

As shown in FIG. 3, as the excavator 6 is press-fitted, pipe bodies 11 are sequentially connected to the upper part, and when the excavator 6 reaches the side shaft 1, the side shaft 1 wall overlaps with the excavator 6 and the reaction force A part of the wall 4 is cut out to establish communication between the inside of the pipe body 11, that is, the inside of the shaft, and the inside of the horizontal shaft 1. The excavator body 8 remains in the ground and becomes part of the shaft wall,
The earth removal pipe 20 is removed if necessary.

Note that, if necessary, a chemical injection work 26 may be provided around the connecting portion between the vertical shaft and the horizontal shaft.

(Effects of the Invention) This invention is as described above, in which an excavator main body, which is provided with a cutting edge at the lower part, an upwardly directed earth discharge pipe, and is provided with a traction means inside, is operated by the traction means. Since the excavator is press-fitted into the ground by applying traction force to multiple tows stretched between the ground surface and the shaft, there is no need to install a traction device to pull the excavator body into the shaft. Furthermore, since the excavated soil is discharged upward through the pipe that forms the shaft wall, there is no need for the troublesome work of dropping the excavated soil into an existing horizontal shaft and discharging it from there.
Moreover, in order to install the excavator, there is no need to previously excavate any kind of vertical shaft that connects the surface and the existing horizontal shaft, which greatly reduces construction time and costs, and also reduces the traction force exerted on the cable. Since the force can be received by the shaft wall, there is no need to install any equipment on the ground to receive the reaction force, and the work space on the ground can be taken up, allowing the work to be carried out smoothly. There is an effect that it can be done.

[Brief explanation of drawings]

1 to 3 are longitudinal sectional views showing the construction procedure of the method of this invention, and FIG. 4 is a longitudinal sectional view showing an example of an excavator.
FIG. 5 is a longitudinal sectional view of the same as above when press-fitted. 1... Horizontal shaft, 2... Ground surface, 3... PC steel wire, 4
...Reaction wall, 5... Anchor, 6... Excavator, 7...
...Blade mouth, 8... Main body, 11... Tube body, 14... Traction jack, 15... Rod part, 16... Chuck device, 17... Chuck part.

Claims (1)

[Claims] 1. When constructing a vertical shaft that connects the existing horizontal shaft from the ground surface, connect the ground surface and the existing horizontal shaft with multiple cables installed vertically, with a cutting hole at the bottom, and an upwardly directed earth discharge pipe. By applying a traction force to the cable using the traction means provided inside the cylindrical excavator body, the excavated soil is discharged to the ground surface by the earth discharge pipe toward the existing horizontal shaft. A method for constructing a shaft, the method comprising: press-fitting the pipe into the excavator, and sequentially connecting a pipe that will become the shaft wall to the upper part of the excavator main body as the pipe is press-fitted.