JPH0552090A - Curve jacking method and propulsion supporter - Google Patents

Abstract

PURPOSE:To provide the curve jacking method and propulsion supporter generating no local stress concentration on the end face of a buried pipe, capable of preventing the breakage of the buried pipe, generating no V-shaped gap between end faces of the buried pipes, requiring no sealing work, and applicable to a small-diameter buried pipe 8. CONSTITUTION:Propulsion supporters 20 provided with direction changing means 30, 40 in the middle of the axial direction are connected in sequence behind a leading body 10, a buried pipe 60 provided with a flexible section 64 in the middle of the axial direction is inserted into the propulsion supporter 20, and the front section 60a and the rear section 60b of the buried pipe 60 are held and fixed to the front section 20a and the rear section 20b of the propulsion supporter 20 by a holding/fixing means such as an expansion system 50 provided on the propulsion supporter 20. Propulsion force is applied to the propulsion supporters 20 while the propulsion supporters 20 and the buried pipe 60 are bent at a preset angle, and the buried pipe 60 is curvedly propelled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curved propulsion method and a propulsion support, and more specifically, when burying an underground burial pipe such as a sewer pipe, a burial hole is directly formed in the ground without excavating the ground. In the so-called propulsion method of burying the buried pipe in the formed burial hole while forming, especially the method of constructing a curved portion, that is, the curve propulsion method and the use of this curve propulsion method to form the burial hole The present invention relates to a propulsion support that is connected to the rear of a front conductor to propel the front conductor or hold and fix an embedded pipe to propel it.

[0002]

2. Description of the Related Art Since the propulsion method does not require wide excavation of the ground along the buried route, research and development is being promoted as a method suitable for construction sites where there is a lot of traffic and it is difficult to restrict traffic. And in burial construction such as sewer pipes,
The buried pipe may be buried in a curved shape in order to change the direction of the sewer pipe and avoid obstacles.

Conventionally, in order to apply the propulsion method to a curved portion,
First, a plurality of direction control jacks are provided in the circumferential direction of the front conductor provided with an earth auger and a compacting head, and by expanding and contracting the direction control jack, the front conductor is deflected and directed in a predetermined curved direction. Make it In this state, if a propulsive force is applied to the tail end of the buried pipe row with a pushing jack, etc., the leading conductor is propelled in the curved direction to form a curved buried hole, and the buried pipe also has this curved shape. It is designed to be fed along the buried hole of.

Since the buried pipe itself has the same straight cylindrical shape as the normal straight part, the end faces of the buried pipes propelled along the curved part have a V-shaped gap between the inner and outer sides of the curvature. There will be a drop. The V-shaped gap is closed and sealed from the inner surface side after the buried pipe is laid.

[0005]

However, in the conventional curve propulsion method as described above, there are problems that the buried pipe may be damaged or accidents in which propulsion is impossible frequently occur. This is because when the embedded pipe is propelled to the curved portion, the propulsive force is transmitted from the rear in a state where the end faces of the embedded pipes have a V-shaped gap as described above. That is, on the end face of the buried pipe, the propulsive force is applied only to a part inside the curve, and a large concentrated part is generated in this part. As described above, the stress concentration occurs in a part of the buried pipe, so that the buried pipe is deformed or damaged, and in severe cases, the promotion of the buried pipe becomes impossible.

In order to solve the above problems, in the prior art disclosed in Japanese Patent Publication No. 1-56240, a plurality of opening adjusting members are sandwiched between the end faces of the buried pipe to propel the curved portion. At this time, by adjusting the length of the opening adjusting member, it is possible to propel it in an accurate curved shape in a state where the end faces of the buried pipe are connected by the opening adjusting member at any of the inner and outer circumferences of the curved portion. I have to. In this method, the propulsive force is transmitted between the embedded pipes via the opening adjusting member on both the inner peripheral side and the outer peripheral side of the curved portion,
Large stress concentration does not occur only at one point inside the curved portion.

However, even in the above method, since the force for linearly propelling the rear buried pipe along the axial direction is transmitted to the front buried pipe whose axial direction is deviated by a certain angle, the curved portion is curved. There is a difference in the force transmitted between the inner peripheral side and the outer peripheral side, that is, the stress generated on the end face of the buried pipe, and by necessity, a larger stress is generated on the inner peripheral side of the curved portion than on the outer peripheral side. Therefore, even with this method, there remains a problem that the inner peripheral side of the curved portion is easily deformed or damaged at the end surface of the buried pipe.

Further, in the above-mentioned prior art, there is a problem that it takes time and effort to mount the opening adjusting member between the end faces of the front and rear buried pipes during the construction, and the work efficiency is lowered.
Further, in any of the conventional curve propulsion methods, after the construction, it is necessary to seal the V-shaped gap generated on the end faces of the buried pipes from the inside, and this sealing work is performed by the operator. Since it is necessary to enter the inside to perform the work, it is very troublesome and increases the work time and the construction cost. In particular, when the diameter of the buried pipe is small and an operator cannot enter the buried pipe, the curving propulsion method cannot be applied because the sealing work cannot be performed.

Therefore, the object of the present invention is to solve the problems of the prior art in the above-mentioned curved propulsion method, to prevent local stress concentration on the end face of the buried pipe, and to ensure the damage of the buried pipe. In addition to the above, the V-shaped gap does not occur on the end faces of the buried pipes, the sealing work becomes unnecessary, and the curved propulsion method for the small-diameter buried pipes that the operator cannot enter inside. It is to provide a method that can also be applied to. It is also to provide a propulsion support for use in such a method.

[0010]

In the curved propulsion method according to the present invention for solving the above-mentioned problems, a buried pipe is buried along the curved buried hole while forming a curved buried hole with a lead conductor. In the curving propulsion method, a propulsion support body, in which a front portion and a rear portion are integrally connected to each other, is sequentially connected to a rear portion of a front conductor through a bendable deflecting means in the middle of an axial direction. An embedded pipe in which the front part and the rear part are integrally joined via a flexible part that can be bent in the middle of the axial direction is inserted into the outer periphery of the shaft, and is held and fixed in the front part and the rear part of the propulsion support. The front portion and the rear portion of the buried pipe are held and fixed to the front portion and the rear portion of the propulsion support body by means, respectively, and the front portion and the rear portion of each propulsion support body are fixed at a predetermined angle by the deflection means. Turn it around and apply propulsion to the propulsion support. By goes by promoting buried pipe curved.

As the lead conductor, the same one as used in the ordinary propulsion method is used. The outer diameter of the leading conductor is set according to the outer diameter of the buried pipe to be laid. For the leading conductor,
It is equipped with excavating means such as an auger and a compaction head for the ground, and forms a buried hole as the lead conductor is promoted. Further, there is also one provided with a mechanism for circulatingly supplying muddy water from the conductor to the ground surface and discharging the excavated earth and sand together with the muddy water. The front conductor may be provided with a turning means such as a direction control jack for changing the direction of the tip. As the specific structure of the diverting means, the same structure as that of the diverting means for the leading conductor in the ordinary propulsion method can be applied. It should be noted that the leading conductor itself may not be provided with a turning means, but the turning direction of the leading conductor may be changed only by the turning means for the propelling support described later.

The propulsion support is in the form of a shaft made of a cylinder having a diameter slightly smaller than the inner diameter of the buried pipe to be laid. Inside the propulsion support, an auger screw that drives the earth auger of the front conductor to send the excavated earth and sand backward, and hydraulic and pneumatic piping that operates the deflection means of the front conductor,
A power cable etc. are accommodated. The propulsion support body is divided into two in the middle of the axial direction, and a deflection means is provided between the divided front portion and rear portion. The diverting means connects the front part and the rear part in the axial direction so that they can integrally move and transmit a propulsive force, and the connected front part and the rear part can be freely moved at a predetermined angle in the axial direction. It can be changed to. Usually, as the diverting means, a connecting means for connecting the front part and the rear part in a freely bendable state and an angle adjusting means for adjusting and fixing the angle formed by the front part and the rear part to a desired angle are provided. The connecting means and the angle adjusting means may be configured by the same mechanism.

Specifically, as a connecting means, for example, if a hinge mechanism is provided at symmetrical positions on the outer peripheries of the opposed end faces of the front part and the rear part, the hinge mechanism is used as a pivot and the front part and the rear part are connected. The part can be bent freely. However, the angle between the front portion and the rear portion cannot be determined only by the connecting means as described above. Therefore, angle adjusting means is required. As the angle adjusting means, screw jacks, hydraulic / pneumatic cylinders, and other expansion / contraction mechanisms are provided at a plurality of positions on the outer circumference between the opposed end faces of the front portion and the rear portion. By adjusting the amount of expansion and contraction of the expansion and contraction mechanism at these multiple locations, the distance between the end faces of the front part and the rear part changes depending on the location, and as a result, the axial direction of the front part and the rear part can be adjusted to an arbitrary angle. It becomes possible to fix. Since the expansion / contraction mechanism such as a screw jack can bear a certain amount of load, the angle adjusting means can also function as the connecting means. As the connecting means and the angle adjusting means, other than the above, as long as they can perform the same function, it is possible to use the connecting structure and the angle adjusting structure in various ordinary mechanical devices in combination.

The operation of the angle adjusting means may be manually operated for each individual propulsion support, but the angle adjusting means is electrically or hydraulically / pneumatically controlled so as to be connected and propulsion-embedded. A number of propulsion support angle adjustment means,
The operation may be collectively controlled outside the buried hole or on the ground. By doing this, from the straight part to the curved part of the burial hole, bend the front part and the rear part of the propulsion support body at the required angle for each construction position, and lay the buried pipe in a desired trajectory. be able to.

Further, if the propulsion support is provided with an angle detecting means such as a sensor capable of detecting an angle formed by the axial direction of the front part and the rear part, the buried hole is obtained based on the detection signal of the angle detecting means. That is, it is possible to know the curvature and bending direction of the curved portion of the buried pipe. Further, by controlling the operation amount of the angle adjusting means based on the detection result of the angle detecting means, the propulsion direction of the buried pipe can be controlled more accurately.

At both ends of the propulsion support, that is, at the front end of the front portion and the rear end of the rear portion, it is preferable to provide rigid connection portions for connecting and fixing the propulsion support members to each other. The rigid connecting part is a connecting structure that can rigidly and integrally fix the connecting parts, such as flange connection using normal bolts, so as not to bend each other, and is used to connect the propulsion supports used in known propulsion methods. A structure similar to the means applies.

The propulsion support is provided with holding and fixing means for holding and fixing the buried pipe in each of the front part and the rear part. The holding and fixing means holds and fixes the embedded pipe from the inner surface of the embedded pipe in a state where the embedded pipe is inserted into the outer periphery of the propulsion support, and counteracts the frictional resistance force applied from the ground to the embedded pipe during propulsion to prevent the embedded pipe from moving. It may be fixed to the propulsion support. In particular,
For example, on the outer periphery of the propulsion support, an expansion body made of a rubber bag or the like that expands when a pressure medium such as air is supplied is provided.
If the inflatable body is inflated and pressed against the inner surface of the embedded pipe, the embedded pipe can be held and fixed to the inflatable body by the friction supporting force acting between the inflatable body and the embedded pipe.
Further, a friction holding plate that mechanically moves from the outer periphery of the propulsion support to the embedded pipe side to press the inner surface of the embedded pipe is provided, or an appropriate locking uneven portion is provided on the inner surface of the embedded pipe. An engaging member that engages with the engaging concave and convex portion may be installed on the propulsion support. In addition, a holding structure or a fixing structure in an ordinary mechanical device can be applied. A more specific structure of the holding and fixing means is described in Japanese Patent Application No. Sho 63-298619, which the present inventors previously invented and applied for a patent.
It is disclosed in Japanese Patent Application Nos. 1-183272 and 1-240408.

As the buried pipe, those having arbitrary materials and dimensions such as sewer pipes and electric wire pipes can be used, and specifically, fume pipes, reinforced resin pipes, vinyl chloride pipes, steel pipes, etc. The pipe material to which the usual propulsion method can be applied can be freely used. The present invention can exert the most preferable effect when a PVC pipe or the like having a relatively poor axial load bearing capacity is used. The diameter and length of the buried pipe can be freely set.

In the present invention, as the buried pipe, one in which the front portion and the rear portion are integrally joined via a bendable flexible portion midway in the axial direction is used. The position of the flexible portion is arranged at a position corresponding to the installation position of the above-mentioned propulsion support deflecting means. The connecting parts of the front part and the rear part of the flexible part are closely joined so that there is no gap. The material of the flexible part is
A material is used that is deformable to the extent that it can be bent according to the curvature of the curved portion of the buried pipe and that has sufficient mechanical strength or durability to form a part of the buried pipe after construction. As the specific structure of the flexible part, an annular flexible part made of an elastically deformable material such as rubber or elastic resin is sandwiched between the front part and the rear part of the buried pipe to be bonded or bolted. It may be fixed integrally by rivet connection, concavo-convex fitting, metal fitting, or other fastening means. The flexible portion may be deformed only by elastic deformation of the material itself, or may be a flexible structure such as a bellows.

Both ends of the buried pipe are the same as a normal buried pipe.
It is preferable to provide a fitting portion for fitting and connecting the buried pipes, a fitting step portion for fitting a fitting collar, and the like. Since the embedded pipe is held and fixed to the above-mentioned propulsion support, the embedded pipes are also linearly connected at their ends, similarly to the connection point between the propulsion supports. Even if the embedded pipes are connected together without a gap, the sealing function can be achieved to some extent, but the joints between the embedded pipes are connected and fixed by bonding, heat fusion, or another ordinary joining means to seal the seam. If you put
Even if the work of sealing the connection portion between the buried pipes is not performed after the construction, the sealing can be surely performed.

A curve propulsion method using each device member having the above structure will be described. It is normal to form a buried hole by excavating a vertical shaft at an appropriate distance in the ground of the route where the buried pipe is laid and propelling the front conductor into the ground from the side of this vertical shaft. It is the same as the propulsion method. In the present invention, the propulsion support body in which the embedded pipe is inserted and retained and fixed is sequentially added to the rear of the front conductor by utilizing the rigid connection portion. The operation of connecting the propulsion support and the buried pipe is performed in the same manner as the conventional ordinary propulsion method. In this state, a propulsion force is applied to the propulsion support by using a push jack installed in the shaft. The propulsive force applied to the propulsion support body is sequentially transmitted to the front propulsion support body and is also transmitted to the embedded pipe through the holding and fixing means. The propulsion force is also transmitted to the leading edge conductor to propel the leading conductor.

Next, when the propulsion method is applied to the curved portion, the deflecting means of the lead conductor is operated to change the traveling direction of the lead conductor. This is similar to the conventional curve propulsion method. When the lead conductor turns, the propulsion support and the buried pipe that follow must also be propelled in turn. Therefore, the deflection means of each propulsion support is operated by a predetermined angle according to the deflection angle of the leading conductor, that is, the curvature of the buried hole, and the angle formed by the front portion and the rear portion is changed. Then, also in the embedded pipe held and fixed to the propulsion support, the front portion and the rear portion are bent at the flexible portions by a predetermined angle. As a result, the propulsion support and the buried pipe are propelled while smoothly changing their directions according to the curvature of the buried hole.

If the leading conductor is propelled to the intended shaft,
The lead conductor and the propulsion support are removed from the burial hole, leaving only the burial pipe in the burial hole. At this time, while holding and fixing the embedded pipe by the holding and fixing means of the propulsion support, the connection between the propulsion supports is also released, and the propulsion supports are sequentially removed. The subsequent steps are carried out in the same manner as in the ordinary propulsion method, but in the present invention, the connecting portions of the buried pipes can be integrally connected without a gap, and the flexible portion bent at the curved portion is Since it is integrally joined to the rear portion, it is not necessary to perform the work of filling the V-shaped gap generated between the end faces of the buried pipe, unlike the conventional curve propulsion method.

In the above construction, if the burial hole formed between the starting shaft and the target shaft, that is, the laying route of the buried pipe is only the curved portion having the same curvature, the diverting means of each propulsion support is It may be fixed at a fixed angle. However, when the curvature of the curved portion changes depending on the location, or when the curved portion and the straight portion are mixed, the turning angle of the turning means is changed stepwise or depending on the passage position of the embedded pipe and the propulsion support. Need to change continuously.
Thus, when it is necessary to change the turning angle during propulsion, it is very convenient to allow the angle adjusting means of the turning means to be remotely operated from the ground or the like, as described above. .. As can be seen from the above description, the curved propulsion method according to the present invention can be applied not only to the construction of the curved portion but also to the construction site where the curved portion and the straight portion are mixed.

[0025]

[Operation] With the embedded pipe held and fixed to the propulsion support,
If this propulsion support is connected to the rear of the leading conductor and a propulsion force is applied to the propulsion support, the propulsion force is transmitted from the propulsion support that is held and fixed to the buried pipe. There is no need to transfer propulsive force between the end faces of the tube.

The propulsion support member can change the angle formed by the front portion and the rear portion thereof by the changing means, and the buried pipe also bends at the front portion and the rear portion through the flexible portion. If possible, the embedded pipe can also be bent in accordance with the bending angle of the propulsion support, and the embedded pipe can be propelled along an arbitrary curve together with the propulsion support. As a result, even if the embedded pipe is propelled through the curved embedded hole, no external force acts on the end faces of the embedded pipes. In addition, since the propulsion support and the buried pipe can be bent by the deflecting means and the flexible portion and can be propelled while accurately and smoothly changing the direction along the curvature of the curved portion, when propelling the curved portion. Also, the resistance force of the ground applied to the buried pipe is extremely small, and the biased force is not applied to the buried pipe.

Therefore, unlike the conventional curve propulsion method, the problem of localized stress concentration due to the imbalance of the transmission force applied to the end surface of the buried pipe is solved, and the buried pipe is propelled even if the curved portion is propelled. There is no possibility of damage or damage to the propulsion. In addition, in the present invention, since the propelling support and the buried pipe are bent in the middle in the axial direction, the propelling supports are connected to each other and the buried pipes are connected to each other by flange coupling, as in the conventional propulsion method. Since a rigid body-like connection structure by fitting or fitting can be applied, the work of connecting the propulsion support and the buried pipe is easy, and the work efficiency is high.

[0028]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a construction state of the curved propulsion method for a horizontal cross section of the ground. First, the leading conductor 10 is arranged at the head. The leading conductor 10 is
The outer diameter is cylindrical, and the tip 11 is conically pointed and inclined inward, and the tip 11 is pushed toward the ground. The earth and sand taken inside the tip 11 is
It is sent to the rear of the front conductor 10 and finally discharged from a shaft (not shown).

A propulsion support 20 is connected behind the front conductor 10. The propulsion support body 20 is in the form of a shaft made of a fixed-length steel pipe or the like, and its tip is connected to the back of the front conductor 10 by a pivotable hinge mechanism 12. Propulsion support 20
The front conductor 10 and the front conductor 10 are also connected to each other by expansion / contraction mechanisms 14 and 14 provided at a plurality of positions on the outer circumference. The propulsion support bodies 20 are sequentially connected to the rear, and the rearmost end of the propulsion support bodies 20 reaches a starting shaft and is connected to a propulsion force adding means such as a push jack.

FIG. 2 shows the structure of the propulsion support 20,
The front portion 20a and the rear portion 20b are arranged with a certain gap therebetween, and both are arranged by the hinge mechanism 30 and the angle adjusting means 4.
They are connected together via 0. An annular flange portion 24 that extends outward is provided at the front end of the front portion 20a and the rear end of the rear portion 20b. When connecting the propulsion support members 20 to each other, the flange portions 24, 24 are aligned and fastened and fixed with bolts or the like. Front part 20a and rear part 2
At a facing portion of 0b, a hinge mechanism 30 is provided at diametrically opposite positions on the outer circumference, and at a position orthogonal to the hinge mechanism 30, the telescopic cylinder serving as an angle adjusting means on the inner surface side of the front portion 20a and the rear portion 20b. A mechanism 40 is provided. On the outer periphery of the front portion 20a and the rear portion 20b, an expansion mechanism 50 formed of a ring-shaped rubber tube serving as a holding and fixing means is provided. The expansion mechanism 50 includes the front portion 2
A pair is provided near both ends for each of 0a and the rear part 20b.

As shown in FIG. 4 or 5, the hinge mechanism 30 includes a hinge plate 34 extending integrally from the front portion 20a and a hinge plate 32 extending integrally from the rear portion 20b. The hinge pin 36 is fitted and connected integrally therewith, and the front portion 20a and the rear portion 20b can be turned or bent in a direction orthogonal to the axis of the hinge pin 36.

The telescopic cylinder mechanism 40 is a cylinder device that operates hydraulically or pneumatically.
Is supported by the front portion 20a by a rotatable support portion 46,
The piston shaft 43, which operates to project from the cylinder body 42,
It is supported by the rear portion 20b by a swingable support portion 48. Therefore, from the cylinder body 42 to the piston shaft 43
By moving in and out, the front portion 20a and the rear portion 20a
A force acts in the direction of moving b away from each other or moving them closer together. When the piston shafts 43 of the two telescopic cylinder mechanisms 40 facing each other are operated in opposite directions, the front part 20a and the rear part 20b connected by the hinge mechanism 30 are connected.
Swivels about the hinge pin 36 to move the propulsion support 2
0 will bend at the center in the axial direction.

The expansion mechanism 50 is provided with a tubular expansion body 52 made of an elastic material such as rubber so as to surround the outer periphery of the propulsion support body 20. The expander 52 is attached and fixed to the support frame 54 attached to the propulsion support 20 on the inner peripheral side. A supply / discharge unit (not shown) for supplying and discharging a pressure medium such as compressed air to the expansion body 52.
Is provided. A valve or the like for normal pressure piping is attached to the supply / discharge unit. The plurality of expanders 52 included in the propulsion support 20 may be connected to each other by pressure piping. However, it is preferable that the pressure pipe extending over the front portion 20a and the rear portion 20b is provided with a bendable joint portion or is configured by a flexible pipe so that the propulsion support 20 can be bent. In addition, the expansion bodies 52 of the propulsion support body 20 that are connected to each other in the front-rear direction can be connected to each other by pressure piping.

FIG. 3 shows the structure of the buried pipe 60.
The embedded pipe 60 is divided into a front portion 60a and a rear portion 60b, and a flexible portion 64 is arranged between the two portions 60a and 60b. Front part 60a and rear part 60
b is formed of a vinyl chloride pipe or the like, like a normal buried pipe. The flexible portion 64 is made of an elastically deformable material such as rubber. The flexible portion 64 and the front portion 60a and the rear portion 60b are integrally joined by means such as adhesion.
Therefore, the buried pipe 60 can be bent at the flexible portion 64. Fitting step portions 66 are formed at both ends of the embedded pipe 60, and when the embedded pipes 60 are axially connected to each other, a cylindrical collar 68 or the like is formed on the fitting step portions 66 of the adjacent embedded pipes 60. Are fitted and connected and integrated. An adhesive is applied to the connecting surface as needed. In addition, in this invention, since the propulsive force or the like is not transmitted between the buried pipes 60, the connecting strength between the buried pipes 60 is not so required, but after the construction, from the connecting portion between the buried pipes 60 to the ground. It is preferable to securely fix and seal the connecting portion so that the earth and sand and water inside do not enter.

When the pressure medium is introduced into the expander 52 with the above-mentioned buried pipe 60 fitted in the outer periphery of the propulsion support 20, the expander 52 is removed as shown in FIG. 4 or FIG. It expands toward the outer circumference, and the outer surface of the expander 52 is pressed against the inner surface of the buried pipe 60. Expander 52
If a certain pressure is applied to the buried pipe 60 from the
Since a frictional supporting force is generated between the embedded pipe 60 and the embedded pipe 60, the embedded pipe 60 is securely held and fixed to the propulsion support 20 without being displaced in the axial direction. By changing the amount or pressure of the compressed air introduced into the expander 52, the pressing force, that is, the holding and fixing force with respect to the buried pipe 60 can be adjusted. When the pressurized air introduced into the expander 52 is released, the holding and fixing of the buried pipe 60 is released, and the buried pipe 6 is released.
The propulsion support 20 can be extracted from zero.

It should be noted that the expansion bodies 52 provided on the front portion 20a and the rear portion 20b of the propulsion support member 20 are replaced by the buried pipe 60.
Since the inner surfaces of the front portion 60a and the rear portion 60b are in contact with each other, when the propulsion support body 20 is bent, the embedded pipe 60 is also bent according to the bending state of the propulsion support body 20. As a means for holding and fixing the buried pipe 60,
When the expansion mechanism 50 as described above is used, the expansion body 52 elastically abuts against the inner surface of the embedded pipe 60, so that the inner surface of the embedded pipe 60 is not damaged or deformed, and is securely held and fixed. can do. Also, the buried pipe 6
Even if there is a variation or error in the inner diameter of 0, it can be absorbed by the elastic deformation of the expander 52. Since there is no complicated operation mechanism, there is little possibility of failure, and the embedded pipe 60 can be held and fixed and released easily and reliably only by controlling the supply of the pressure medium.

A curved propulsion method using the propulsion support 20 and the buried pipe 60 described above will be described. Propulsion of the front conductor 10 from the inner surface of the shaft into the ground to form the buried hole is performed in the same manner as in a normal propulsion method. A propulsion support 20 is connected to the rear of the front conductor 10 via a hinge mechanism 12 and an expansion / contraction mechanism 14. At this time, after the embedded pipe 60 made of a vinyl chloride pipe or the like is fitted around the outer periphery of the propulsion support body 20, pressurized air is introduced into each of the expansion bodies 52 of the propulsion support body 20 to expand the same, and The embedded pipe 60 is held and fixed.

If a propulsion force is applied to the rearmost end of the propulsion support body 20 connected to the rear of the front conductor 10 from the push jack in the vertical shaft, the front conductor 10 and the propulsion support body 20 are propelled into the ground. A buried hole is formed by the front conductor 10. A buried pipe 60 held and fixed to the propulsion support 20.
Is also propulsively embedded in the embedding hole together with the propulsion support 20.
To the rear end of the propulsion support body 20, the propulsion support body 20 holding and fixing the buried pipe 60 is sequentially added.

Next, as shown in FIG. 1, a curved buried hole is formed in the front conductor 10, and the buried pipe 60 is driven and buried in the curved buried hole. First, the propulsion direction of the leading conductor 10 is changed by the changing means or the like provided in the leading conductor 10. In the illustrated embodiment, the length of the expansion / contraction mechanism 14 that connects the lead conductor 10 and the propulsion support 20 is changed to redirect the lead conductor 10. If the direction in which the leading conductor 10 advances changes and the buried hole becomes curved, the propulsion directions of the subsequent propulsion support 20 and the buried pipe 60 must also be changed.

Therefore, as shown in FIG. 4, the propulsion support 2
By operating the telescopic cylinder mechanism 40 of 0, the front portion 20a
The angle formed by the axial direction of the rear portion 20b is changed according to the curvature of the curved portion. The front portion 60a and the rear portion 60b of the buried pipe 60 are respectively connected to the propulsion support 2 through the expansion mechanism 50.
Since the embedded pipe 60 is held and fixed to the front portion 20a and the rear portion 20b of 0, the flexible portion 64 of the embedded pipe 60 elastically expands and contracts to change the angle formed by the front portion 60a and the rear portion 60b. At this time, in the diametrical direction of the flexible portion 64, one side is stretched and the other side is deformed so as to be compressed. As a result, the buried pipe 60 is bent at the flexible portion 64.

The propulsion support 20 and the buried pipe 60 whose central portion is bent at a predetermined angle are smoothly propelled according to the curvature of the buried hole. When changing the curvature of the burial hole, the tip conductor 10 is turned to change the propulsion direction, and the propulsion support 20 is also turned to sequentially adjust the turning angles of the propulsion support 20 and the buried pipe 60. in this way,
If the deflection angles of the propulsion support 20 and the buried pipe 60 can be arbitrarily set, the buried hole or the laying route of the buried pipe can be freely designed. For example, when changing the laying route of the buried pipe by a constant angle, instead of the conventional method of immediately connecting from the straight line portion to the straight line portion in the target direction via the arc-shaped curved portion having a constant curvature, gradually change from the straight line portion. It is also easy to design a laying route for an extremely complicated curved pipe, such as connecting to a straight line in the desired direction while gradually decreasing the curvature after increasing the curvature and increasing the curvature. You can do it.

[0042]

As described above, according to the curved propulsion method and the propulsion support body of the present invention, first, the buried pipe is held and fixed to the propulsion support body only, and the propulsive force is transmitted by the buried pipe itself. Since it is not necessary to do so, almost no external force acts on the end faces of the buried pipes. Moreover, since the buried pipe and the propulsion support can be freely turned or bent according to the curvature of the buried hole, the buried pipe can be curved very smoothly and accurately even when constructing a curved portion. It will be laid.

Since there is no concern that local stress concentration will occur on the end surface of the buried pipe, the problem that the buried pipe is damaged or cannot be propelled during the curved propulsion method is completely solved. The reliable, quick and stable laying work of the buried pipe can be performed. In particular, with the conventional curve propulsion method, it is now possible to apply the curve propulsion method to PVC pipes, etc. that could not be applied due to poor axial load bearing capacity, expanding the range of application of the curve propulsion method. It can be planned.

Moreover, in the present invention, since the propulsion support and the buried pipe are deflected or bent by the deflection means or the flexible portion provided in the middle of the axial direction, the connection between the propulsion supports and the buried pipe are performed. The simple rigid connection structure in the conventional ordinary propulsion method can be adopted as it is, the connection work of the propulsion support and the buried pipe is easy, the construction efficiency is high, and the whole work can be performed by applying the curved propulsion method. It does not deteriorate the sex.

[Brief description of drawings]

FIG. 1 is a sectional view of a construction state showing an embodiment of the present invention.

FIG. 2 is a partially cutaway front view of a propulsion support.

FIG. 3 is a sectional view of the buried pipe.

FIG. 4 is an enlarged sectional view showing a bent portion of the propulsion support and the buried pipe.

5 is an enlarged sectional view in a direction orthogonal to FIG.

[Explanation of symbols]

 10 Leading conductor 20 Propulsion support 30 Hinge mechanism (coupling means) 40 Telescopic cylinder mechanism (angle adjusting means) 50 Expansion mechanism (holding and fixing means) 60 Buried pipe

Claims (3)

[Claims] 1. In a curve propulsion method in which a buried pipe is formed along a curved buried hole while forming a curved buried hole in the curved conductor, the curved pipe is formed in the middle of the axial direction behind the front conductor. The propulsion support body, in which the front portion and the rear portion are integrally connected, is sequentially connected via the diverting means, and the front portion is provided on the outer periphery of the propulsion support body through a flexible portion that is bendable midway in the axial direction. The embedded pipe in which the front portion and the rear portion are integrally joined is inserted, and the front and rear portions of the embedded pipe are connected to the front portion of the propulsion support body by holding and fixing means provided in the front portion and the rear portion of the propulsion support body, respectively. And fixed to the rear part respectively, and the front part and the rear part of each propulsion support member are deflected at a predetermined angle by the deflecting means, and a propulsive force is applied to the propulsion support member so that the embedded pipe is Curved propulsion method characterized by propelling in a curved shape .. 2. The front and rear propulsion supports are rigidly connected so as not to bend at their joints, and the joint between the buried pipes held and fixed by the front and rear propulsion supports is fixed and sealed. The curved propulsion method according to claim 1, wherein the curved propulsion method is used. 3. A propulsion support body which is sequentially connected to the rear side of a front conductor, and in which an embedded pipe is inserted and held and fixed on the outer periphery, and which is forward and rearward via a bendable deflecting means in the middle of the axial direction. The propulsion support body is characterized in that it is integrally connected to the portion, and both ends in the axial direction are provided with rigid connection means that can be fixedly connected to the rear of the leading conductor or to another propulsion support body.