JPH05280281A - Double steel pipe for propulsion - Google Patents

Abstract

PURPOSE:To make a buried pipe stronger and prevent depression of a ground surface by providing a ring member surrounding an inner pipe in the circumferential direction and an outer pipe slidably supported with the ring member, and opening a grout hose inserting hole on the ring member. CONSTITUTION:Against a double steel pipe 1' for propulsion of which a part of the rear end is projected into a shaft, the front end face of the inner pipe 2 of a new double steel pipe 1 for propulsion is contacted with the rear end face 2c' of the inner pipe 2' of the double steel pipe 1' for propulsion. Next, the contacted part is welded and coated with a polyethylene tube 20, and grout hoses 6, 6' are connected together. Next, the outer 3 is frontward slided against the inner pipe 2 and a ring part, the front end face 3b of the outer pipe 3 is contacted with the rear end face 3c' of the outer pipe 3', the pusher ring 21 of the double steel pipe 1 is pushed with propulsive hydraulic jacks 22, and the double steel pipe 1 is propelled into the earth. Cement milk is made to flow in the grout hose 6, so that the space between the outer wall of the inner pipe 2 and the inner wall of the outer pipe 3 may be filled with the milk, water and soil in the space are made to flow outside the outer pipe 3 through a check valve 9, and the outer wall of the outer pipe 3 is also covered with cement milk.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double steel pipe for propelling, for example, a gas pipe, having a double pipe structure, which is suitable for a propulsion method of burying in the soil by propelling the soil.

[0002]

2. Description of the Related Art For example, a double steel pipe in which concrete or the like is poured between an inner pipe and an outer pipe is used as a pipe to be buried in soil for sending high-pressure gas in order to maintain the strength of the pipe. May be used. Also, when burying this double steel pipe in the soil, instead of excavating and burying a long and narrow groove along the route to be buried from the ground, a predetermined vertical shaft is dug and the horizontal wall of this vertical shaft A so-called propulsion method in which a double steel pipe is buried by propelling it in the longitudinal direction may be adopted.

FIG. 8 is a side view (a) and a sectional view (b) showing an example of a conventional double steel pipe for propulsion used when adopting the propulsion method as described above. This double steel pipe 31
Has as its basic structure an inner pipe 33 and an outer pipe 35, and a concrete 37 filling between the inner pipe 33 and the outer pipe 35.
Consists of. Here, the front end portion 33a and the rear end portion 33b of the inner pipe 33 are not covered with the concrete 37 and are exposed.

Prepare a number of such double steel pipes 31,
Propulsion into the soil in the direction indicated by the arrow in the figure,
The rear end surface 33d of the inner pipe 33 of the double steel pipe 31 which has already been propelled
And the front end surface 33c of the inner pipe 33 of the new double steel pipe 31 are brought into contact with each other and welded, and a ring-shaped member having a shape divided into a plurality of rings is fitted to this welded portion and is already propelled. The rear end face 35b of the outer pipe 35 of the double steel pipe 31 and the front end face 35a of the outer pipe 35 of the new double steel pipe 31 are connected, and then the rear end face 33 of the inner pipe 33 of the new double steel pipe 31 is connected.
Thrust is applied to d and the rear end surface 35b of the outer tube 35 to propel it in the direction of the arrow. By repeating this many times, the double steel pipes 31 connected to each other are buried in the soil.

[0005]

When the conventional double steel pipe as described above is used, the rear end face 3 of the inner pipe 33 is driven by propulsion.
For example, bending or scratching occurs in 3d, and a step of shaping the rear end face 33d before the welding of the next double steel pipe with the inner pipe is necessary. In addition, this propulsion causes an internal stress in the inner pipe 33, and the inner pipe 33 is buried while being used and is used.
3 may have a pinhole or a crack.

In view of the above circumstances, the present invention provides a double steel pipe for propulsion that does not require a step of shaping the rear end surface of the inner pipe and can be propelled without causing internal stress in the inner pipe. The purpose is to

[0007]

A dual steel pipe for propulsion according to the present invention for achieving the above object comprises an inner pipe, and a ring member fixed to the inner pipe and surrounding the inner pipe in the circumferential direction. And an outer tube slidably supported by the ring member. Here, it is preferable that a grout hose insertion hole is formed in the ring member, and the propulsion double steel pipe is provided with a grout hose extending in the longitudinal direction of the propulsion double steel pipe through the grout hose insertion hole.

Alternatively, the ring member is provided with an insertion hole through which the grout hose insertion tube is inserted, and the propulsion double steel pipe extends through the insertion hole and extends in the longitudinal direction of the propulsion double steel pipe. It may be configured to include a grout hose insertion tube having an outflow hole. In the configuration including the grout hose insertion tube, the filler outflows only to the front end portion and / or the rear end portion of the grout hose insertion tube so that the connection portion of the propelling double steel pipes connected to each other is filled with the filler. You may provide a hole.

Further, the propulsion connected to the front end or the rear end of the outer pipe, to the rear end of the outer pipe of the double steel pipe for propulsion connected to the front side in the propulsion direction, immediately after the double steel pipe for propulsion. It is also preferable to provide a guide member for guiding the front end of the outer pipe of the double steel pipe for use, which is slid between the double steel pipe and the ring member. Further, it is also preferable that the outer pipe is provided with a check valve that allows unidirectional outflow from the inside of the outer pipe to the outside.

[0010]

The double steel pipe for propulsion of the present invention has a structure in which the ring member and the outer pipe slide, and the thrust is applied only to the outer pipe to damage the rear end surface of the inner pipe. The double steel pipe for propulsion can be buried in the soil by applying the propulsion method without attaching it and without causing internal stress in the inner pipe. The occurrence of cracks and the like is prevented, and highly reliable construction is possible.

When propelling the double steel pipe for propulsion into the soil, for example, after the inner pipes are brought into contact with each other and welding is performed,
A method of abutting the outer pipes and applying a thrust to the outer pipes to propel the whole is adopted. Here, by providing the above-mentioned guide member in the above-mentioned double steel pipe for propulsion, when the outer pipe is slid, the error of the positional deviation of the outer pipe is absorbed, and the end face of the outer pipe is pushed. Can be accurately brought into contact with each other.

Further, when the outer pipe has sufficient rigidity, it is not always necessary to fill the space between the outer pipe and the inner pipe with a filler such as cement milk, but from the viewpoint of durability, It is preferable to fill a space between the inner tube and the inner tube. In this case, if the above-mentioned grout hose is provided, when connecting the double steel pipes for propulsion, this grout hose is also connected, and a large number of double steel pipes for propulsion are connected. After the propulsion, the filler can be fed into the grout hose while removing the grout hose to fill the space between the outer tube and the inner tube. Here, instead of the grout hose, the grout hose insertion tube is provided and the grout hose insertion tube is connected when connecting the double steel pipe for propulsion, and the grout hose itself is connected to the grout hose after the propulsion. It may be inserted into the hose insertion tube.

Here, concrete or the like is preliminarily filled between the outer pipe and the inner pipe other than the connection portion to which the propelling double steel pipe is connected, and the outer pipe is filled with the filled concrete or the like. It is also conceivable to construct a double steel pipe for propulsion that is devised so that it slides. In this case, since the portion to be filled with the filler after propelling is only the upper connection portion, it is considered that the work at the site is easy. However, in the case of a double steel pipe for propulsion prefilled with concrete in this way, it is a challenge to make sure the outer pipe slides securely, and the outer pipe of the two double steel pipes for propulsion connected is If there is misalignment, it is difficult to correct it due to the rigidity of concrete, etc. Also, it is difficult to carry because it is heavy and it is difficult to handle at the site. In any case, it is indispensable to perform the filling work on site, and the double steel pipe for propulsion of the present invention is superior as a whole.

If the outer pipe is provided with the above-mentioned check valve, it is difficult for water, earth and sand to enter between the inner pipe and the outer pipe during propulsion,
Even if it gets in, the water, earth and sand, etc. will be pushed out of the outer pipe by the filling pressure when the above-mentioned filler is filled, and the filler will be caught between the inner pipe and the outer pipe. It will be fully spread in the open space. Further, the filler itself flows out of the outer pipe through the check valve, and the overfilled space near the outer wall of the outer pipe is filled with the filler, so that the buried pipe becomes stronger.

[0015]

EXAMPLES Examples of the present invention will be described below. FIG. 1 is a side view along the longitudinal direction of a double steel pipe for propulsion according to an embodiment of the present invention, FIG. 2 is a sectional view of the double steel pipe for propulsion shown in FIG. 3 is an enlarged side view of a portion indicated by a circle A in FIG. 1. Here, as an example, a double steel pipe for propulsion for gas will be described.

FIG. 1 shows a double steel pipe 1'for propulsion in a state in which it has been already propelled into the soil and only a part of the rear end side projects into the shaft.
And the new double steel pipe 1 for propelling, which is connected to the rear end of this double steel pipe for propelling 1'and is propelled into the soil together with this double steel pipe for propelling 1 '. These propulsive double steel pipes 1 and 1'have the same structure. The basic structure of the double steel pipe for propulsion 1 is an inner pipe 2 of about 900 mmφ made of a steel pipe and about 120 mm of a steel pipe.
0 mmφ outer tube 3 and 2 between these inner tube 2 and outer tube 3
It is composed of a ring member 4 arranged at a position.
Here, the ring member 4 has a grout hose insertion hole 4
c (see FIG. 4) is formed, and the grout hose 6 is inserted into the grout hose insertion hole 4c.

The outer pipe 3 has check valves 9 which open when pushed from the inside of the pipe and close when pushed from the outside of the pipe. It is provided on the top, bottom, left and right of. As shown in FIG. 3, a guide ring 10 which is a guide member according to the present invention is provided at the front end of the outer pipe 3, and the outer pipe 3 of the propulsive double steel pipe 1 is a ring member as described later. When sliding on 4 and moving forward, the guide ring 10 enters the inside of the outer pipe 3'of the double steel pipe for propelling 1'from the rear end face 3c 'side. Along with this, the front end surface 3b (see FIG. 3) of the outer pipe 3 of the double propelling steel pipe 1 and the outer pipe 3'of the double propelling steel pipe 1 '.
The rear end face 3c 'contacts. Since the guide ring 10 is provided in this way, even if there is a slight positional deviation between the outer pipes 3 and 3 ', the error is absorbed and the outer pipes 3 and 3'abut accurately.

The outer surface of the inner tube 2 is coated with polyethylene 7. As shown in FIG. 1, after the front end face of the inner pipe 2 of the double propelling steel pipe 1 and the rear end face of the inner pipe 2'of the double propelling steel pipe 1'are brought into contact with each other, The pipes are welded, and after this welding, the welded part is newly covered with a polyethylene tube for corrosion protection from the outer surface. Next, the ring member will be described.

FIG. 4 is a perspective view showing a part of the ring member, FIG. 5 is a side view (a) and a front view (b) thereof, and FIG.
[Fig. 2] is a partially enlarged view showing a ring member of the double steel pipe for propulsion shown in Fig. 1. However, in FIG. 4 and FIG. 5, the rubber disc 13 shown in FIG. 6 is omitted in order to avoid complication of illustration. The ring member 4 is composed of a circular tubular bottom plate 4a that holds the inner pipe 2 and ribs 4b that stand up from the bottom plate 4a. Further, the ring member 4 is composed of two members in which the ring is divided in half for the convenience of mounting, and these two members surround the inner pipe 2 in the circumferential direction thereof and are bolted to each other. The ring member 4 is fixed to the inner pipe 2. The outer wall of the inner tube 2 is coated with polyethylene 7 as described above, and the rubber plate 11 is arranged on the inner wall of the ring member 4 so that the polyethylene coating is not damaged when the ring member 4 is fixed. Has been done. Further, the rubber plate 12 is also sandwiched in a portion of the ring member 4 where two members each having a half shape are bolted. Further, the rib 4b of the ring member 4 is provided with a grout hose insertion hole 4c.

As shown in FIG. 6, a rubber disc 13 is adhered to the rib 4b of the ring member 4 so that the inner wall of the outer tube 3 directly contacts the rubber disc 13. It is configured. As will be described later, the rubber disc 13 is provided with the inner pipe 2 when the inner pipe 2 and the outer pipe 3 are concentric circles.
When filling the space between the outer tube 3 and the outer tube 3 with the cement milk, the filled cement milk is prevented from leaking a large amount into the adjacent space beyond the space divided by the two ring members 4. In this case, it is sufficient to fill only the above-mentioned space of the connection portion of the two propulsion double steel pipes 1 and backfill the two spaces. The space sandwiched by the member 4 may not be filled. However, when the inner pipe 2 and the outer pipe 3 are not concentrically arranged, the ring member 4 is prevented from flowing cement milk over the space partitioned by the ring member 4 into the adjacent space. Therefore, in this case, if the cement milk is filled only in the connecting portion of the two propelling double steel pipes, the cement milk flows over the gap of the ring member 4 into the adjacent space, By this, the cement milk is filled in the entire space sandwiched by the inner tube 2 and the outer tube 3, and backfilling is also performed. Further, the inner wall surface of the outer tube 3 is supported only by the rubber disk 13, so that the outer tube 3 slides reliably and easily with respect to the inner tube 2 and the ring member 4. Figure 7
FIG. 7 is a schematic diagram showing a propulsion construction procedure for burying a propulsive double steel pipe having the structure shown in FIGS. 1 to 6 in the soil along with the steps thereof.

As shown in FIG. 7 (a), it is assumed that the double steel pipe for propelling 1'is already propelled into the soil by the propulsion method and a part of its rear end projects into the shaft. For the propulsive double steel pipe 1 ′ whose part of the rear end protrudes into the vertical shaft, a new propulsive double steel pipe 1 is prepared, and the front end surface 2 b of the inner pipe 2 and the propulsive secondary pipe 2 already propelled. The propulsive double steel pipe 1 is arranged so that the rear end surface 2c 'of the inner pipe 2'of the heavy steel pipe 1'abuts (see FIG. 1).

Next, as shown in FIG. 7 (b), the rear end surface 2c 'of the inner pipe 2'of the double steel pipe for propulsion 1'and the front end of the inner pipe 2 of the double steel pipe for propulsion 1 which are in contact with each other. The surface 2b is welded,
The state after welding is inspected using X-rays, and if this inspection is passed, the welded portion is covered with the polyethylene tube 20. As mentioned above, the polyethylene coating 7 is formed on the outer wall of the inner pipe 2 also on the portion other than the welded portion.

Next, as shown in FIG. 7 (c), the grout hoses 6 provided on the double steel pipes 1 and 1'for propulsion are connected. However, here, at one place that will eventually be located near the center by being connected and propelled, it is possible to pull out the connected grout hose half and half from the front and the rear in the propulsion direction. ,
Do not connect.

After that, the outer pipe 3 is slid forward with respect to the inner pipe 2 and the ring member 4 from the state shown in FIG. 7 (c) to the state shown in FIG. 7 (d). The front end face 3b of 3 contacts the rear end face 3c 'of the outer tube 3'.
After that, as shown in FIG. 7 (e), a push ring 21 is applied to the rear end of the propulsion double steel pipe 1 so as to contact only the rear end surface 3c of the outer pipe 3, and the push ring 21 is pushed. The propulsion hydraulic jack 22 is set to the outer pipe 3, and the thrust is applied to the outer pipe 3 so that the propulsion double steel pipe 1 is connected further forward than the propulsion double steel pipe 1 ′ and the propulsion double steel pipe 1 ′. It is propelled into the soil together with the same type of double steel pipe for propulsion. here,
A not-shown excavation head is attached to the front end of the foremost double-stage steel pipe for propulsion, which allows the propulsion while advancing. The push wheel 21 and the propulsion hydraulic jack 22 may be set before the outer pipe 3 is slid forward, and the propulsion hydraulic jack 22 may slide the outer pipe 3.

After the propulsion through the above-described steps over a large number of propulsion double steel pipes, the grout hose 6
(See Fig. 2) Pour cement milk into the ring member while pulling it out one by one so that it is sequentially arranged between the ring member and the ring member of the propulsive double steel pipe to which many tips of the grout hose are connected. , And the space defined by the outer wall of the inner tube 2 and the inner wall of the outer tube 3 are sequentially filled. In this case, when pulling out the grout hose 6 rearward in the propulsion direction, cement milk flows out from the grout hose insertion hole 4c (see FIG. 4) of the front end side ring member of the double steel pipe for propulsion arranged at the front end in the propulsion direction. It is preferable to close this hole 4c so that it does not get stuck. When each space is filled with cement milk, this cement milk causes the water, earth and sand, etc. that have entered between the inner pipe 2 and the outer pipe 3 to flow out of the outer pipe 3 via the check valve 9. At the same time, the cement milk itself flows out via this check valve, and
As shown in (f), the outer wall of the outer tube 3 is also covered with cement milk. As a result, this buried pipe becomes stronger, and it is also possible to prevent the subsidence of the ground surface.

Although the grout hose 6 is inserted into the insertion hole 4c formed in the ring member 4 in the above embodiment, the grout hose itself can be inserted after the completion of the propulsion and before the filling of the cement milk. is there. In this case, a pipe provided with a cement milk outflow hole in advance is passed through the insertion hole 4c of the ring member 4 and connected through this pipe in the step shown in FIG. 7 (c). A grout hose may be inserted in the pipe.

As an example, a gas having a gas pressure of 70 kg / cm ² is caused to flow inside the inner pipe of the double steel pipe buried in the soil. It should be noted that although a double steel pipe for propulsion for gas has been described here, it goes without saying that the present invention is not limited to that for gas.

[0028]

As described above, in the double steel pipe for propulsion of the present invention, the ring member is arranged between the inner pipe and the outer pipe to provide a predetermined gap between the inner pipe and the outer pipe. Since the outer pipe is made to slide with respect to this ring member, a thrust can be applied only to the outer pipe, and a propulsion method that does not cause the inner pipe end face to collapse or the inner pipe to generate internal stress, etc. It has been realized, which enables reliable pipe burial.

Here, in the case where the above-mentioned guide member is provided, the error in the positional deviation of the outer tube is absorbed. Also,
When a grout hose or a grout hose insertion pipe is provided, the gap between the inner pipe and the outer pipe can be filled with a filler to form a strong buried pipe, and if the check valve described above is provided, water, earth and sand, etc. The outer wall of the outer tube can be covered with a filler.

[Brief description of drawings]

FIG. 1 is a side view along a longitudinal direction of a double steel pipe for propulsion according to an embodiment of the present invention.

2 is a cross-sectional view of the propulsive double steel pipe shown in FIG. 1 as viewed from the right side of FIG.

FIG. 3 is an enlarged side view of a portion indicated by a circle A in FIG.

FIG. 4 is a perspective view showing a part of a ring member.

FIG. 5 is a side view (a) and a front view (b) showing a part of a ring member.

6 is a partial enlarged view showing a ring member of the double steel pipe for propulsion shown in FIG.

FIG. 7 is a schematic diagram showing a propulsion construction procedure for burying a propulsive double steel pipe having the structure shown in FIGS. 1 to 6 in the soil along the steps thereof.

FIG. 8 is a side view (a) and a sectional view (b) showing an example of a conventional double steel pipe for propulsion used when adopting a propulsion method.

[Explanation of symbols]

1,1 'Double steel pipe for propulsion 2 Inner pipe 3 Outer pipe 4 Ring member 6 Grout hose 7 Polyethylene coating 9 Check valve 10 Guide ring 11, 12 Rubber plate 13 Rubber disc

[Procedure amendment]

[Submission date] September 10, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

Although the grout hose 6 is inserted into the insertion hole 4c formed in the ring member 4 in the above embodiment, the grout hose itself can be inserted after the completion of the propulsion and before the filling of the cement milk. is there. In this case, a pipe provided with a cement milk outflow hole in advance is passed through the insertion hole 4c of the ring member 4 and connected through this pipe in the step shown in FIG. 7 (c). A grout hose may be inserted in the pipe. Figure 9
Is a schematic section of a double steel pipe for propulsion according to another embodiment of the present invention.
It is a side view. Inner tube 2 and outer tube 3 are concentrically arranged (see Figure 2).
And the diameter of the inner tube 2 and the diameter of the outer tube 3 are not so different.
If not, the space between the inner pipe 2 and the outer pipe 3 is narrow, so
You must use a small-sized hose 6.
Yes. In this case, since the diameter of the grout hose 6 is small,
Fill the space between the inner tube 2 and the outer tube 3 with cement milk
Of the cement milk released from the grout hose 6
The amount is small, which makes it possible to move away from the grout hose 6.
The space cannot be filled with cement milk
The problem may occur. This case is shown in Figure 9.
As described above, the inner pipe 2 and the outer pipe 3 are not arranged concentrically and
Take a large part of the space between the outer tubes 3
Use a large diameter grout hose 6 in the closed space
As a result, the above problem can be addressed.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] Figure 9

[Correction method] Added

[Correction content]

FIG. 9 is a schematic cross-sectional view of a double steel pipe for propulsion according to another embodiment of the present invention.

[Procedure amendment 3]

[Document name to be corrected] Drawing

[Correction target item name] Figure 9

[Correction method] Added

[Correction content]

[Figure 9]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akitaka Fujita 1-7-7 Suehiro-cho, Tsurumi-ku, Yokohama Inside Tokyo Gas Co., Ltd. Conduit Technology Center (72) Inventor Shingo Nagashima 1-cue, Suehiro-cho, Tsurumi-ku, Yokohama 7-7 Tokyo Gas Co., Ltd. Conduit Technology Center (72) Inventor Akira Adachi 3-17-8 Matsunami, Chiba City (72) Inventor Tomoya Fujimoto 2-3-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Kawasaki Steel Works Ltd. (72) Inventor Shigeru Morishita 2-3-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Kawasaki Steel Co., Ltd.

Claims (6)

[Claims] 1. An inner tube, a ring member fixed to the inner tube and surrounding the inner tube in a circumferential direction, and an outer tube slidably supported by the ring member. Double steel pipe for propulsion. 2. The ring member has a grout hose insertion hole, and the propulsion double steel pipe includes a grout hose extending in the longitudinal direction of the propulsion double steel pipe through the grout hose insertion hole. The double steel tube for propulsion according to claim 1. 3. The filler outflow, wherein the ring member has an insertion hole through which a grout hose insertion tube is inserted, and the propulsion double steel pipe extends in the longitudinal direction of the propulsion double steel pipe through the insertion hole. The double steel pipe for propulsion according to claim 1, further comprising a grout hose insertion pipe having a hole. 4. A front end portion of the grout hose insertion tube and / or a front end portion of the grout hose insertion tube so that a connecting portion of the propelling double steel tubes connected to each other is filled with a filler.
Alternatively, the double steel pipe for propulsion according to claim 3, wherein the filler outflow hole is provided only in the rear end portion. 5. A front end portion or a rear end portion of the outer pipe, which is connected to a rear end of the outer pipe of the double steel pipe for propulsion connected to a front side in a propulsion direction, immediately after the double steel pipe for propulsion. The double steel pipe for propulsion according to claim 1, further comprising a guide member for guiding the front end of the outer pipe slid between the double steel pipe for propulsion and the ring member. 6. The double steel pipe for propulsion according to claim 1, wherein the outer pipe is provided with a check valve that allows one-way outflow from the inside of the outer pipe to the outside.