JP2003232467A - Pipe inserting construction method and pipe joint structure used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow an advancing new pipe P to have the largest possible diameter relative to a shield pipe P'. <P>SOLUTION: A spigot 1 of the pipe P is inserted in a socket 2 of the preceding pipe P, and the pipes P are advanced in the shield pipe P' while being joined to newly install a pipeline. In the pipe joint structure, the spigot 1 is movable relative to the socket 2 by a required length within a range of not slipping out in the axial direction. A driving force transmission material 14 interposed between the end of the socket 2 and a flange 20 fixed to the outer periphery of the spigot 1 by welding, has strength to transmit driving force, and in advancing, the tip of the spigot 1 is positioned in the middle of the movable required length. When large compressive force such as an earthquake is applied, the driving force transmission material 14 is contracted or crushed to allow the expansion of the spigot 1 to the socket 2. The flange 20 is provided with protective rods 24 covering the outer surface of the driving force transmission material 14. With the protective rods 24, the pipes P are smoothly guided in the shield pipe P' while preventing the damage of the driving force transmission material 14. Since the protective members 24 can be made thin, the bores of the pipe P' and pipes P can be made close. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe insertion construction method (pipe-in-pipe construction method) for laying fluid transportation pipes used for water supply, gas, sewerage, etc. without cutting and a seismic propulsion pipe joint structure used therefor. is there.

[0002]

2. Description of the Related Art As a construction method for burying fluid transport pipes such as ductile cast iron pipes, an open-cut construction method in which the ground is excavated and laid is generally used. Due to the increasing volume, it is difficult to cut off traffic due to the excavation method. For this reason, only the starting shaft and the reaching shaft are excavated, and the fume pipe and the steel pipe are sheathed as a sheath pipe, and then the ductile cast iron pipe is inserted after the embedding, and the existing pipe is used as the sheath pipe. In-pipe insertion methods such as a pipe-in-pipe method in which a new pipe with a small diameter is inserted to renew the pipeline have been widely adopted.

In the pipe-in-pipe construction method, as shown in FIG. 17, a new pipe P having a smaller diameter than that is inserted and laid in an existing pipe P'which is buried between a starting pit S and a reaching pit R. A hydraulic jack J is installed in the start pit S, and the rear portion of the hydraulic jack J abuts the reaction force receiver H,
The front portion presses the new pipe P via a push angle B. The new pipes P are sequentially joined by inserting the insertion opening 1 at the front end thereof into the receiving opening 2 at the rear end of the preceding new pipe P,
It is pushed into the existing pipe P '. The new pipe P at the beginning
A leading sled K for reducing the insertion resistance is attached to the tip of the.

By the way, in recent years, a pipe line is also required to have earthquake resistance, and as a pipe joint structure having the earthquake resistance, there is a pipe joint structure in which the insertion port 1 can be expanded / contracted (removable / removable) within a required range. . In this seismic resistant pipe joint structure, the projection at the tip of the insertion opening 1 is brought into contact with the lock ring and the rear end portion which are separated by a predetermined length on the inner surface of the receiving opening 2 to expand and contract within the required range and the insertion opening 1 Prevents slip-out and insertion (see Examples).

When adopting this kind of seismic resistant pipe joint structure in the above-mentioned propulsion method, it becomes a problem whether the new pipe P is laid while securing the expansion and contraction allowance within the above required range.
It is to position the insertion protrusion in the middle of the lock ring and the rear end and to drive it. As a technology that solved that problem,
As disclosed in Japanese Patent Laid-Open No. 2000-248770, FIG.
20 to 20.

[0006] This technique relates to an NS joint structure, in which a protrusion 3 is provided at the tip of the insertion opening 1 and a lock ring 5 is provided on the inner surface of the receiving opening 2 via a centering rubber 4, and a rubber ring for sealing is provided at the receiving opening 2. 6, the insertion opening 1 is inserted, and the propulsive force transmission material 8 made of low-foamed polystyrene or the like is interposed between the flange 7 on the outer peripheral surface of the insertion opening 1 and the end surface of the receiving opening 2.

In this technique, during propulsion, the propulsive force transmitting material 8 keeps the tip (projection 3) of the insertion slot 1 in the middle of the expansion / contraction allowance L ₀ as shown in the figure, and the ground movement such as an earthquake occurs. At times, the propulsive force transmission member 8 contracts or collapses, so that the insertion port 1
Moves in the axial direction by the amount of the shrinkage allowance L ₁ to absorb the fluctuation, and prevents further shrinkage to prevent damage to the joint.

[0008]

In the above technique, the new pipe P is smoothly propelled in the sheath pipe P '.
A caster 10 is provided at the fastening portion of the flange 7, and the caster 10 is largely projected from the outer peripheral surface of the receiving port 2 and the propulsive force transmitting material 8. Therefore, the size of the sheath P'with respect to the new pipe P is increased by 3 calibers, for example, in the case of the new pipe P: φ600, the sheath P ': Is difficult to promote.

At this time, when the sheath pipe P'is newly buried, the sheath pipe P'may be of a required size, but in the case of the old existing pipe P ', In order to secure the flow rate of the existing pipe P ′, it is preferable that the new pipe P has a water passage cross-sectional area as close as possible to the existing pipe P ′. If possible, reduce the diameter by one, for example, existing pipe P ': φ9
If 00, it is preferable that a new pipe P: φ800 can be promoted.

According to the present invention, a new pipe P'having a large diameter is used as long as a new pipe P can be formed, so that a new pipe having a water passage cross-sectional area close to that of an existing pipe can be obtained. The task is to do.

[0011]

In order to achieve the above object, the present invention first adopts the technique shown in FIGS. 18 to 20 and uses the propulsion force transmitting material to expand and contract the expansion allowance L _0.
It was decided to secure. This is because the propulsion force transmitting material can accurately set the degree of contraction / collapse by considering its composition, and the reliability of the insertion / expansion action of the insertion opening when the ground changes.

Next, according to the present invention, instead of the casters, a sled member is used to guide the new pipe.
This is because the sled member can reduce the height. Further, according to the present invention, the warp-like member is covered and protected by the sled member. The sled member prevents the propulsive force transmitting material from coming into contact with the inner surface of the sheath tube.If the propulsive force transmitting material comes into contact with the sheath, the damage may be caused. , The amount of propulsive force transmitted is reduced and it becomes difficult to obtain the required expansion and contraction allowance.

Specifically, around the flange for supporting the above-mentioned propulsive force transmitting material, or around the propulsive force transmitting material protecting ring interposed between the propulsive force transmitting material and the receiving port, at required intervals. The protective rod extending to the outer periphery of the propulsion force transmission material was provided.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION As an embodiment of the present invention,
Insert the pipe into the receiving port of the preceding pipe and splice it into the sheath, and in the pipe insertion method of constructing a new duct by propelling into the sheath, insert the insertion port into the receiving port and insert it into the receiving port. In a pipe joint structure capable of moving a required length within the range in which the mouth does not come off in the axial direction, the tip of the insertion opening is in the middle of the required length that can be moved, and an annular shape is provided on the outer circumference of the insertion opening outside the receiving opening. The flange is fitted and fixed, and the propulsive force transmitting material is interposed between the flange and the receiving end, and the propulsive force transmitting material has the strength to transmit the propulsive force and is resistant to a large compressive force such as an earthquake. The contraction or crushing allows the insertion of the insertion opening to the receiving opening, and a structure in which a protective rod reaching the outer surface of the propulsion force transmitting material at a required interval is provided around the flange. obtain.

In this structure, a protective rod is not provided on the flange, but a required protective ring is provided around the propulsion force transmission material protection ring fitted around the insertion opening between the propulsion force transmission material and the end face of the receiving opening. It is also possible to adopt a structure in which the protective rods are provided at intervals.

With the pipe joint structure having these configurations, in the pipe insertion method, if the receiving port and the insertion port are joined, the propulsive force is secured by the propulsive force transmitting material during the propulsion of the pipe, which causes a hindrance. Instead, the tube is propelled. At that time, the protective rod guides the damage and prevents the propulsive force transmitting member from being damaged. After installation, if a large ground movement such as an earthquake occurs, the compressive force due to the change causes the propelling force transmission material to contract or collapse, and the insertion opening expands or contracts with respect to the receiving opening.
It corresponds to the ground movement. That is, it exerts an earthquake resistance function.

[0017]

EXAMPLE An example of a pipe joint structure is shown in FIGS. 1 to 5, which is an S-shaped joint structure of a ductile cast iron pipe P, in which a tip 3 of the insertion port 1 and a receiving port Lock rings 5 are respectively provided on the inner surfaces of 2, and after inserting the insertion opening 1 into the receiving opening 2 with the rubber ring 6 and the backup ring 6a interposed, the push ring 9 is attached to the rubber ring 6 via the split ring 9a. The rubber ring 6 is pushed and sealed by screwing the fastening bolt 12 into the receiving port 2 through the push ring 9 and fastening.

An annular flange 20 is fitted on the outer periphery of the insertion opening 1 on the outside of the receiving opening 2, and a propulsive force transmitting material is interposed between the flange 20 and the stud bolt 12 (end surface of the receiving opening 2). 14 are provided. The propulsive force transmitting member 14 has an annular shape, but may be divided in the circumferential direction and may be intermittent at that time. The point is that it should have strength against the propulsion force. For example, when the propulsive force transmitting material 14 is a high-strength material such as concrete or foam concrete described later, and the annular shape is too strong, there is a possibility that smooth contraction / compression is not performed, as shown in FIG. In addition, the peripheral divided pieces 14a are preferably arranged and the divided pieces 14a are arranged at appropriate intervals.

The propulsive force transmitting material 14 is, for example, a high-strength resin foam having a compressive stress of 1 to 30 kgf / cm ² (≈0.1 to 3 MPa) (expansion rate of 5 times or more that of the resin alone), The elastic limit stress is changed by changing the expansion ratio. Examples of the material of the propulsion force transmitting material 14 including the resin foam include polystyrene, polyurethane, concrete containing a static crushing agent disclosed in JP-A-2000-80889, and foaming thereof. The material is typical. As a matter of course, other resin material or hard paper such as cardboard, foam metal, or the like, which has the desired transmission of propulsive force and contractibility, may be used. Further, a resin container filled with a liquid or a gas can be an effective means.

The propelling force transmitting material 14 will be described in more detail. The propulsive force transmitting material 14 is elastically deformed by a compressive force of a propulsive force during construction, so that the propulsive force is transmitted, but the amount of distortion remains. Otherwise, if the propulsion is removed (propulsion ends), restore. On the other hand, when a compressive force above the elastic limit stress acts, the amount of strain increases in the plastic region, and when a compressive force above a certain level acts, the strain progresses with a predetermined thickness left. Stop. The elastic limit stress, the range of the plastic region, the state in which the strain has progressed and the final thickness in the crushed state are the propulsion force transmission material 1
When 4 is a foam material, it can be adjusted by the expansion ratio. The following conditions can be considered as a method for setting the expansion ratio.

When the pressing force acting is about the propulsive force, the stress value is within the elastic limit stress. Therefore, the expansion ratio and the like are set so that the elastic limit stress σ ₁ has the following relationship (the propelling force is normally transmitted). To prevent this, the propulsion force transmission member 14 is prevented from being plastically deformed during propulsion). σ ₁ > (F / A) = σ _max where F: propulsion force, A: propulsion force transmission area,
σ _max : Stress generated in the propulsive force transmitting material 14.

On the other hand, due to an earthquake etc.
When a force is applied, the propulsion force transmission material 14 is placed in the plastic region.
Therefore, the amount of distortion of the propulsion force transmission member 14 increases. this
Prevents seismic joints from separating when pushing force occurs when an earthquake occurs
It is the same as the force 0.3d (tf) (d: nominal diameter)
If the pushing force is applied due to an earthquake, etc.
Allowance T + L₁Propulsion force transmission material 14 is compressed and length
It becomes T. At this time, L ₁Set to be 1% of pipe length
If this is done, it means that the pushing margin can be secured. Figure 8
(A) indicates that when a large pulling force is applied,
Also, (b) shows that when a large pushing force is applied
Each one is represented. When pulling it out, move the insertion slot 1
The propulsive force transmission material 14 may also move, and conversely,
In some cases, the lunge 20 and the propulsion force transmission member 14 may slip and not move.
is there. In addition, this propulsion force transmission material 14 must be interposed
This allows the cushioning action based on its elasticity when driving a curve.
It goes without saying that stress concentration can be prevented more.

As shown in FIG. 5, the protective ring 13 is provided with a collar 13a at a part of its peripheral edge.
It is positioned (centered) by applying it to the upper surface of the. By interposing this protection ring 13, the force from the bolt 12 is transmitted to the entire abutting surface of the propulsion force transmission member 14 without being concentrated. As far as this transmission is concerned, the ring 13 can be divided and may be intermittent. The collar 13a may also be omitted.

The flange 20 has a cross section L as shown in FIG.
It is formed into a saddle band shape by being divided into four equal parts, and a fastening piece 22 is provided at both ends of the divided piece 21, and a rib 23 is provided in the middle. Each fastening piece 22 and rib 23 is provided with a protection rod 24 extending to the entire width of the outer peripheral surface of the propulsion force transmission member 14, and each protection rod 24 surrounds the entire perimeter of the propulsion force transmission member 14 in a frame shape (basket shape). I'm out. The thickness of this protective rod 24 is
As long as there is no obstacle, it is preferable that it is thin, and
The protective rods 24 are preferably arranged at equal intervals around the pipe, and the number thereof is arbitrary. Fastening piece 2 of adjacent divided pieces 21, 21
A bolt / nut 25 is inserted between 2 and 22, and by fastening the bolt / nut 25, the flange 20
Is reduced in diameter and pressed against the outer peripheral surface of the insertion opening 1. Flange 2
A stud can be provided on the pressure contact surface of No. 0, and its shape may be a pyramid such as a triangular pyramid, a cone, a prism, a cylinder, or the like, but a pyramid is preferable from the viewpoint of biting.

The configuration of this embodiment is as described above,
In the pipe insertion method shown in FIG. 17, after cleaning the inside of the existing pipe P ′ and inserting the pipe 1 into the receiving port 2 and joining the pipes P and P, first, in FIG. As shown, at the time of joining the joint, the insertion amount of the insertion opening 1 is set to be short and the body length L is set to be long. Further, the protection ring 13 and the like are inserted and placed in the opening 1. In this state, the joints are joined in the usual procedure (Fig. 2 (b)).

Next, the protective ring 13 is shifted to a position where it comes into contact with the head of the bolt 12, and a protrusion 26 is formed on the outer periphery of the insertion opening 1 by welding. Then, a propulsive force is divided into two parts between the protrusion 26 and the protective ring 13. Attach the material 14 in a ring shape,
Further, the flange 20 is fitted and fastened (FIGS. 6C to 6D and FIGS. 7A to 7C). In this state, when a jacking force is applied, the insertion port 1 is inserted up to the position of the specified body dimension L ₁ (Fig. 6 (d), Fig. 7 (c)), and is propelled in this state (Fig. 1). It In this propulsion, even if rolling occurs, the pipe P is supported by one of the protection rods 24 and the propulsive force transmission member 14 is prevented from being damaged.
When the laying of the required length of the pipe P is completed, the mortar a is placed between the existing pipe P ′ and the new pipe P (see FIG. 8).

In this buried state, if an extension force (pulling force) acts on the pipe P, as shown in FIG. 8 (a), if a compressing force (pushing force) acts on the pipe P, the same figure (b). As shown in
One pipe P moves with respect to the other pipe P as indicated by an arrow to absorb the force.

Although the above-mentioned embodiment is the case of the S type joint,
As shown in FIGS. 9 and 10, the present invention can be adopted even in the case of the SII type joint, in which case the protection ring 13 is
As shown in FIG. 5, the cross-section may be U-shaped so as to contact the end surface of the receiving port 2. At this time, as shown in FIG.
And the U-shaped pieces 13c extending from the ring 13b to the end surface of the receiving port 2 at equal intervals in the circumferential direction, and at that time, the both 13b and 13c may be integrated. The U-shaped protection ring 13 can be used in the above-mentioned S-shaped joint. Further, the NS type joint shown in FIG. 11 can also be used in various expansion joints with a separation preventing function such as the PII type joint shown in FIG.

The number of divisions of the flange 20 can be arbitrarily selected such as three divisions. Further, in the embodiment, the movement prevention of the flange 20 is ensured by the welding projection 26. However, if a sufficient fixing force can be exerted by biting the stud or the like, the welding projection 26 can be omitted. Welding protrusion 2
The timing of forming 6 is not limited to the above-mentioned one, but may be arbitrary, for example, after the flange 20 is fitted,
It is also possible to directly weld to the insertion opening 1. Furthermore, the projection 26 may not be formed by welding, but another member may be welded to form the projection 26. The shape and arrangement of the projection 26 are arbitrary, and for example, the aspect of FIG. 13 can be adopted.

In the pipe joint structure having the protective ring 13, the protective rod 24 can be provided on the protective ring 13. For example, as shown in FIGS. 14 and 15, the protective rod 24 is provided on the protective ring 13. Further, the protective rod 24 is formed integrally with the flange 20 and the protective ring 13, but it may be formed separately from them and may be integrated by bolting, welding or the like.

In the above embodiment, the new pipe P is newly installed on the existing pipe P ', but even when the new pipe P is newly installed on the new sheath P', if the present invention is adopted, Of course, it is possible to obtain a new pipe flow path close to the water passage cross-sectional area of the sheath P '.

[0032]

As described above, according to the present invention, the propulsive force transmitting material is used to maintain the expansion and contraction allowance of the insertion port, and the propulsive force is guided by the protective rod while the propulsive force transmitting material is protected. As a result, a new pipe (propulsion pipe) with a water cross-sectional area close to that of a sheath pipe can be adopted.

[Brief description of drawings]

FIG. 1 is a front view of a main part of an embodiment of a pipe joint structure.

FIG. 2 is a cross-sectional view of the main part of the embodiment.

FIG. 3 is a cut left side view of the same embodiment.

FIG. 4 is a view showing a divided piece of the flange of the embodiment, (a) is a left side view, (b) is a front view, and (c) is a right side view.

FIG. 5 shows a protection ring of the same embodiment, (a) is a front view, (b) is a right side view.

FIG. 6 is an operation diagram of an example of the propulsion method according to the embodiment.

[Fig. 7] Operation diagram of the propulsion method

FIG. 8 is an expansion and contraction action diagram of the same embodiment.

FIG. 9 is a sectional view of a main part of another embodiment of the pipe joint structure.

FIG. 10 is a sectional view of a main part of the other embodiment.

FIG. 11 is a sectional view of a main part of the other embodiment.

FIG. 12 is a sectional view of a main part of the other embodiment.

FIG. 13 is a front view of the main part of the other embodiment.

FIG. 14 is a front view of a main part of the other embodiment.

FIG. 15 is a cut left side view of the other embodiment.

FIG. 16 is a diagram showing another example of the propulsive force transmitting material.

FIG. 17 is an explanatory diagram of the sheath tube propulsion method.

FIG. 18 is a front view of a main part of a conventional pipe joint structure.

FIG. 19 is a left side view of the same.

FIG. 20 is a sectional view of the same main part.

[Explanation of symbols]

1 insertion slot 2 mouth 3 Insertion protrusion 5 lock ring 6 Rubber ring for seal 7, 20 Propulsion force transmission material support flange 8,14 Propulsion force transmission material 9 push wheel 13 Protective ring 24 Protective rod 25 Flange fastening bolts and nuts 26 Weld protrusion P new pipe P'sheath pipe (existing pipe)

Continued front page    (72) Inventor Yoshinori Yoshida             1-12-19 Kitahori, Nishi-ku, Osaka City Stock Association             Kurimoto Ironworks F-term (reference) 2D054 AC18 AD28                 3H015 FA08

Claims (3)

[Claims] 1. A receiving port 2 for the pipe P preceding the insertion port 1 for the pipe P.
In the in-pipe insertion method of inserting a pipe into a pipe and propelling it into the sheath P'to newly establish a pipe line, the insertion port 1 is inserted into the receiving port 2
Is a pipe joint structure in which the insertion port 1 can be moved a required length with respect to the receiving port 2 within a range in which the insertion port 1 does not come off in the axial direction, and the tip of the insertion port 1 is in the middle of the required movable length. The annular flange 20 is fitted and fixed to the outer periphery of the insertion opening 1 outside the receiving opening 2, and the propulsive force transmitting material 14 is interposed between the flange 20 and the end of the receiving opening 2. Numeral 14 has the strength to transmit the propulsion force, and contracts or collapses against a large compressive force such as an earthquake to allow the insertion of the insertion opening 1 into the receiving opening 2. A pipe joint structure characterized in that a protective rod 24 is provided around the periphery of the protective rod 24 at a required interval to reach the outer surface of the propulsive force transmitting member 14. 2. A receiving port 2 for the pipe P preceding the insertion port 1 for the pipe P.
In the in-pipe insertion method of inserting a pipe into a pipe and propelling it into the sheath P'to newly establish a pipe line, the insertion port 1 is inserted into the receiving port 2
Is a pipe joint structure in which the insertion port 1 can be moved a required length with respect to the receiving port 2 within a range in which the insertion port 1 does not come off in the axial direction, and the tip of the insertion port 1 is in the middle of the required movable length. The annular flange 20 is fitted and fixed to the outer periphery of the insertion opening 1 outside the receiving opening 2, and the propulsive force transmitting material 14 is interposed between the flange 20 and the end of the receiving opening 2. Numeral 14 has the strength to transmit the propulsive force, and contracts or collapses against a large compressive force such as an earthquake to allow the insertion of the insertion opening 1 into the receiving opening 2. Around the protective ring 13 for propulsion force transmission material fitted around the outer periphery of the insertion port 1 between the transmission material 14 and the end face of the receiving port 2, a protective rod 24 reaching the outer periphery of the propulsion force transmission material 14 is formed at required intervals. A pipe joint structure characterized by being provided. 3. A receiving port 2 for the pipe P preceding the insertion port 1 for the pipe P.
It is an in-pipe insertion method in which a pipe line is newly established by propelling it into the sheath P'while inserting and splicing the pipe into the sheath P ', and the splicing in which the insertion port 1 of the pipe P is inserted into the receiving port 2 is defined by claim 1 or 2. A pipe insertion construction method characterized by having the pipe joint structure described in 2.