JPH0463960B2 - - Google Patents

Description

[Detailed description of the invention] <Field of application of the invention> The present invention relates to a propulsion method.

<Prior Art> Conventionally, there is a propulsion method as shown in Figs. 4 and 5.

That is, the pilot pipe P is forced into the ground from the starting shaft A by the jack B, and is once penetrated to the reaching shaft C.

Next, an expansion head D is attached to the tip of the pilot pipe P, and the pilot pipe P is pushed back from the arrival shaft C toward the starting shaft A, contrary to the previous step.

This pushing back can be carried out by fixing the fume pipe H to the pilot pipe P and pressurizing the fume pipe H with a jack on the reaching shaft C side.

<Problems to be Solved by the Present Invention> The above-mentioned conventional techniques have the following problems.

<B> It is necessary to penetrate the arrival shaft and then return to the starting shaft.

Adopting these two steps obviously requires a long construction time and is uneconomical.

<B> Since the starting shaft requires various equipment, it is inevitable that it will be large.

However, with this construction method, it is necessary to suspend the Huyum pipe from the arrival shaft, so not only the starting shaft but also the arrival shaft must be large.

Therefore, in construction work in cities where land is scarce, securing land for large reaching shafts is a major problem.

<Object of the present invention> The present invention was made in order to improve the above-mentioned problems, and an object of the present invention is to provide the following propulsion method.

<A> Construction method that can be completed with only one construction from the starting shaft to the arrival shaft <B> Construction method that does not require a large arrival shaft <Configuration of the present invention> Next, equipment used in the method of the present invention An example will be described.

<A> Expansion head The expansion head 1 is a conical cylinder, and has a central tube 11 that houses the down-the-hole drill 3 in the center of its tip and projects forward.

Then, an intake port 13 is opened in the conical surface 12 of the widening head 1 to take in small pieces of crushed boulders and earth and sand.

A storage chamber 14 for storing earth and sand is formed as a space on the back side of the conical surface 12.

At the center of the back surface of the storage chamber 14, a hollow drive shaft 21 is provided which rotates the enlargement head 1.

The earth removal screw 2 is rotatably housed inside the drive shaft 21 coaxially with the down-the-hole drill 3 in the center tube 11 .

Further, a ring 15 for supporting the hume tube H is provided around the back surface of the storage chamber 14 in an annular manner.

<B> Down-the-hole drill A down-the-hole drill 3 is housed inside the center tube 11 of the widening head 1.

A publicly known down-the-hole drill 3 itself can be used.

The above-mentioned soil removal screw 2 is attached to the rear of this down-the-hole drill 3, and the storage chamber 14 is
It is constructed so that the earth and sand introduced into the inside can be discharged to the starting shaft A at the rear.

<Operation of the present invention><A> Propulsion A hume pipe H is installed in the ring 15 of the enlarged head 1.
The groups are connected, and the rear ends of the hume tubes H group are pressurized by jack J and pushed into the ground.

<B> Crushing and taking in Crush the boulders, etc. in the center of the expansion head 1 using the down-the-hole drill 3.

Surrounding pebbles, sand, earth and sand, small pieces after crushing, etc. are taken into the storage chamber 14 through the intake port 13 and discharged by the soil removal screw 2.

<C> Penetration Propulsion starts from the starting shaft A, and the expansion head 1 penetrates the arrival shaft C.

Since the enlargement head 1 is followed by the hume pipe H, the conduit is completed when the enlargement head 1 is penetrated.

<Effects of the Present Invention> Since the present invention is as described above, the following effects can be expected.

<B> When the expansion head propelled from the starting shaft penetrates the arrival shaft, the pipeline will be completed at that point, since the expansion head is followed by a group of humm pipes.

Therefore, unlike in the past, there is no need to propel the shaft in the opposite direction to the starting shaft again after reaching the starting shaft, so the construction period can be significantly shortened and the work can be completed at low cost.

<B> The arrival shaft only pulls up the expanded head that has arrived, and does not require a propulsion device in the opposite direction or a space for lowering the hump pipe.

Therefore, the land required for installing the reaching shaft can be sufficiently constructed with a minimum area.

<C> A down-the-hole drill is provided in the center of the widening head.

If this were to be attempted using only the expansion head, the destructive force of the bit of the expansion head would depend on the circumferential speed of rotation, so it would be impossible to crush boulders etc. in the center area where the rotation speed is low.

For this purpose, the apparatus of the present invention employs a method in which a preceding down-the-hole drill is positioned in the center of the device to first perform primary crushing of the center and then take in the material.

Therefore, even in geological strata with many boulders, which could not be carried out using conventional expansion heads, it became possible for the first time to carry out construction by pushing the expansion head into the ground.

[Brief explanation of drawings]

Fig. 1: A perspective view of an embodiment of the widening head used in the construction of the present invention, Fig. 2: A sectional view thereof, Fig. 3:
Explanatory diagram of the construction method of the present invention, FIGS. 4 and 5: Explanatory diagram of the conventional construction method.

Claims (1)

[Scope of Claims] 1. An expansion head which is a funnel-shaped cylinder with both ends open and has a drilling function is used, and a down-the-hole drill is accommodated in the central cylinder constituting the expansion head. Connecting a drive shaft that forms part of the discharge path to the back of the head, housing a rotatable earth removal screw in the drive shaft, and excavating with a down-the-hole drill; and the base end of the drive shaft in the starting shaft. A propulsion method comprising the steps of: giving rotation independently of the discharge screw and excavating with an expansion head; and press-fitting the expansion head in the propulsion direction together with the hume pipe to be propelled from within the starting shaft.