JP4370102B2 - Pulling out and removing existing pipes buried in the ground - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for drawing and removing an existing pipe buried in the ground.
[0002]
[Prior art]
Such existing buried pipes may be removed as necessary when it becomes an obstacle to other civil engineering work, or when replacing the cloth when it is aged or damaged. And it was common to remove the existing buried pipe by the open-cut method.
[0003]
On the other hand, in recent years, there are problems in the above-mentioned excavation method, that is, it is necessary to excavate the entire removed portion of the existing pipe, it is necessary to mount a mountain, and suspension protection is necessary where electric wires are installed. In view of the necessity of backfilling and the need to dispose of the remaining soil, various proposals have been made to remove existing pipes without digging.
[0004]
For example, in Japanese Patent Laid-Open No. 8-28753 and Japanese Patent Laid-Open No. 2000-179749, after forming a shaft that reaches the base end of the existing pipe removal portion, and then separating the removal portion from the remaining portion in front of it, A technique is disclosed in which a removed portion of an existing pipe is pulled out and removed into a vertical shaft through a pressure bearing body fixed in the existing pipe.
[Patent Document 1]
JP-A-8-28753 [Patent Document 2]
JP 2000-179749 A
[Problems to be solved by the invention]
However, in the above prior art, since the drawing is performed through the support body provided in the existing pipe, the drawing force cannot be applied to the existing pipe in a well-balanced manner, and the existing pipe is pulled without breaking. It was difficult.
[0006]
In addition, although the existing pipe receives a strong restraining force from the surrounding ground, the above-mentioned prior art does not perform a process to weaken this restraining force, and the existing pipe is pulled out. Became even more difficult.
[0007]
Then, the main subject of this invention is providing the method which can draw out an existing pipe | tube easily.
[0008]
[Means for Solving the Problems]
The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
When removing the existing pipe buried in the ground, the existing pipe is formed without forming a shaft that reaches the proximal end of the removed part of the existing pipe and that reaches the distal end of the removed part of the existing pipe. In the method of separating and removing the removed portion and the remaining portion, pulling the removed portion into the shaft and removing it,
A ring material that can be divided into a plurality of divided units that can pass through the existing pipe is brought into the space in front of the distal end portion of the removed portion through the existing pipe in a state of being divided into the divided units,
A disc-shaped partition wall that can be divided into a plurality of divided units that can pass through the existing pipe is brought into the space in front of the tip of the removed portion through the existing pipe in a state of being divided into the divided units,
A tensile member is inserted from the removed portion side of the partition wall to the remaining portion side, and a pressure jig that is a member having a width smaller than the inner diameter of the existing pipe is connected to the remaining portion side. ,
Assembling the ring material and the partition,
Wherein engaging the pressing jig in the partition wall, a state in which the partition wall in contact disposed at the distal end surface of the ring member, and contact disposed substantially throughout the annular distal end surface of the removed portion of disconnecting said ring member Then, withdrawing and removing the removed portion into the shaft through the tensile material ,
A method for pulling out and removing existing pipes buried in the ground characterized by this.
[0009]
(Function and effect)
Thus, in the present invention, the substantially whole ring material of the annular tip end surface of the removed portion of disconnecting contact, performs the withdrawal into the vertical shaft through the ring material. Accordingly, the pulling force acts on the entire annular tip surface of the removed portion with a good balance. Needless to say, the tube is very strong against the axial force acting on the end face. Therefore, the removal portion is less likely to be destroyed by the drawing force, and the existing pipe can be drawn and removed more easily.
As for a ring material, it is desirable to set it as the unit structure which consists of a division | segmentation unit of the size which can pass the inside of a pipe | tube as described in this claim. As a result, the pressure bearing member can be brought forward through the narrow existing pipe removal portion.
[0010]
<Invention of Claim 2>
The partition wall is provided with a back-injection hole, and in the space in front of the removal part formed as the removal part is pulled out, the back-in injection hole is inserted through the back-injection hole as the space increases. The method for extracting and removing an existing pipe buried in the ground according to claim 1, wherein the materials are sequentially injected .
[0011]
[0012]
<Invention of Claim 3>
Prior to the extraction step, the friction between the removed portion and the surrounding ground ,
A process of injecting a lubricant into the ground around the removed portion;
Processing to disturb and relax the surrounding ground of the removed portion by liquid jet; and
A process of boring the surrounding ground of the removed part,
The method of pulling out and removing an existing pipe embedded in the ground according to any one of claims 1 to 3, which is reduced by performing at least one treatment .
[0013]
(Function and effect)
Thus, by reducing the friction prior to the drawing step, the friction between the removed portion and the surrounding ground can be reduced, and the existing pipe removing portion can be pulled out after weakening the restraining force by the surrounding ground. Therefore, the removed portion can be pulled out more easily, and troubles such as breakage of the tube are less likely to occur.
[0014]
[0015]
Moreover, the friction between the removed portion and the surrounding ground can be reduced by performing such processing. In particular, injection of a lubricant (a lubricant such as a surfactant liquid as will be described later) is very preferable because it is easy to work.
[0016]
<Invention of Claim 4 >
In reducing the friction, at least the tip portion of the removed portion is removed by a predetermined pushing length, and the removed portion is pushed in with the friction reducing process, and the friction between the removed portion and the surrounding ground. The method of pulling out and removing existing pipes embedded in the ground according to claim 3, wherein
[0017]
(Function and effect)
By pushing the removal part after the friction reduction treatment, the friction between the existing pipe removal part and the surrounding ground is remarkably reduced (hereinafter also referred to as “cutting the friction”), and the removal part can be pulled out more easily.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the embodiment of the present invention will be described in detail with reference to an example in which a sewer pipe having a diameter of 800 mm is removed from a human hole portion over a predetermined length range.
(Vertical shaft formation process)
First, in order to secure an installation space and a work space for the drawing equipment, as shown in FIG. 1, a vertical shaft 2 that reaches the base end portion of the removed portion 1 b of the existing pipe 1 is formed. Specifically, in the case of the present embodiment, the periphery of the existing manhole M is excavated while a liner plate (not shown) is installed, the existing manhole M is removed, and the shaft 2 is formed. As for the size of the vertical shaft 2, it is desirable to secure about 3.5 m which can carry out the existing pipe of a fixed length (2.43 m) as it is.
[0019]
(Friction reduction process-Pretreatment-)
Next, as shown in FIG. 2, the worker enters the existing pipe 1 from the shaft 2, and at least the tip of the removed portion 1b is pushed (destructed) into a predetermined pushing length, for example, a range L of about 10 to 30 cm. Remove. Thereby, in this embodiment, the removal part 1b and the remaining part 1a are cut away.
[0020]
Before and after this, an operator enters the existing pipe 1 and forms a lubricant injection hole 1h at an appropriate position, for example, at the top of the pipe. A plurality of injection holes 1h are preferably provided at a predetermined interval in the tube axis direction, for example, at an interval of about 5 to 10 m. Although a plurality of injection holes 1h can be provided in the circumferential direction of the tube, it is desirable to provide at least at the top of the tube as shown in the figure. Thereafter, the injection pipe 3a is connected to the injection hole 1h, and the lubricant supplied from the lubricant injection plant 3b is injected into the surrounding ground of the removed portion through the injection hole 1h. In the figure, this injection portion is indicated by the symbol X. As this lubricant, a surfactant or the like generally used as a propellant can be suitably used. Thus, friction between the removed portion 1b and the surrounding ground G can be reduced.
[0021]
(Propulsion equipment installation process)
In parallel with or before and after the pretreatment, as shown in FIG. 3, a propulsion facility 4 for pushing and pulling the pipe is installed in the shaft 2. In the illustrated embodiment, reaction force walls 5f and 5b made of concrete or the like are formed on the front and rear wall surfaces in the pushing direction, respectively, and a propulsion base 6 is installed at the bottom, and propulsion jacks 7 and 7 are provided on the propulsion base 6 for propulsion. The reaction force of the jacks 7, 7 is configured to be taken from the reaction force wall 5b.
[0022]
In this process, the installation state for pushing in the existing pipe is shown, and the propulsion jacks 7 and 7 are attached to the rear reaction wall 5b so as to take a reaction force, and the propulsion jacks 7 and 7 and the existing jacks are installed. Between the base end portion of the pipe 1, a ring material 8 that contacts the entire annular base end face of the existing pipe 1 is interposed, and the propulsive force of the propulsion jacks 7, 7 acts on the entire base end face of the existing pipe 1 in a balanced manner. It is supposed to be. The necessary propulsive force is about 60 t when a sewage pipe of φ800 mm is installed with a soil covering of about 7.5 m as in this embodiment.
[0023]
(Friction reduction process-post-treatment-)
After completing the pretreatment and the installation of the propulsion equipment, in this embodiment, the removal portion 1b is pushed in to further reduce the friction, and the friction between the removal portion 1b and the surrounding ground G is cut. Preferably, the removal portion 1b is first slightly propelled, for example, about 10 cm by the propulsion equipment 4, and the necessary thrust is grasped. If the necessary thrust is large and there is a risk of destruction of the removed portion 1b, the length range of about 10 cm is removed in the middle of the removed portion 1b, and the thrust is applied after dividing the removed portion 1b into a plurality of parts. To. Thereby, it can divide | segment in order from the division | segmentation part by the side of a base end, can apply a thrust, and can cut | disconnect friction. On the other hand, if the required thrust is small, push it in as it is and cut the friction.
[0024]
(Supporting body installation process)
Thereafter, as shown in FIG. 4, the support body 10 for pulling out the removal portion 1b is removed from the annular tip surface of the removal portion 1b (or the tip surface of the most advanced division portion when the above-described division is performed). Arrange substantially in contact with the whole.
[0025]
When there is little or no space in front of the distal end portion of the removed portion 1b, the distal end portion of the removed portion is scraped over an appropriate length range, for example, about 20 cm. Thereby, the bearing body installation space and the installation work space S are secured. It is also possible to expand the work space in the radial direction by excavating and removing the surrounding ground G as necessary. When the space S is sufficiently in front of the distal end portion of the removed portion 1b, such a chipping operation is unnecessary. Further, when removing the tip portion for pushing-in as described above, not only the length range L necessary for pushing but also the length necessary for the support body installation space S is secured, and after the removal portion 1b is pushed in In addition, it is possible to leave the pressure bearing body installation space S in front of it, and in this case also, it is not necessary to remove the tip of the removed portion in this step.
[0026]
If the bearing body installation space S is secured, the operator then brings the bearing body 10 into the front space through the existing pipe 1 and removes the bearing body 10 substantially from the entire annular tip surface of the removed portion 1b. Place it in contact with. In the case of adopting such a contact arrangement form, since the outer diameter of the support body 10 must be larger than the inner diameter of the existing pipe 1, the support body 10 has a size that can pass through the existing pipe as shown in FIG. A field assembly type consisting of a plurality of divided units is desirable. Thus, by bringing each unit into the removed portion front space S through the removed portion 1b and assembling it, the bearing body 10 having a diameter larger than the inner diameter of the existing tube 1 can be arranged in front of the existing tube removed portion 1b.
[0027]
More specifically, as shown in FIG. 5, the bearing body 10 of the present embodiment is in contact with the ring material 11 that is in contact with the annular tip surface f1 of the removed portion 1b and the tip surface of the ring material 11. It comprises a partition wall (lid member) 12 for contacting and closing the opening of the ring material 11 and a pressure jig 13 engaged with the partition wall 12. Reference numeral 14 denotes a tensile material for transmitting a drawing force to the bearing body 10, and a PC steel wire or a PC steel rod can be used. As shown in FIG. 4, for example, a plurality of tensile material units are used. 14a can be formed by connecting with a connecting member 14b. As the tension member unit 14a, for example, a screw-type PC steel rod can be used, and as the connecting member 14b, a PC steel nut can be used.
[0028]
As shown in FIG. 6, the ring material 11 has an end surface 11 f that is substantially the same as the cross section of the existing pipe 1 (at least the inner diameter is smaller than the outer diameter of the existing pipe 1). Then, it can divide | segment into the substantially equal three division | segmentation unit 11u by the bolting part shown with a dashed-dotted line. As shown in FIG. 7, the partition wall 12 is a disk-like body having an outer diameter substantially equal to that of the ring material 11 (at least the outer diameter is larger than the inner diameter of the ring material 11), and communicates with the front and back surfaces. Tensile material insertion hole 12a and back-filling injection hole 12b are provided, and in the illustrated example, it can be divided into four substantially equal-sized divided units 12u by bolting portions indicated by alternate long and short dashed lines (less than this) (Or a large number of divisions). In particular, in the illustrated embodiment, the tensile material insertion hole 12a is also formed so that the center of the insertion hole 12a is located on the dividing line so that the tensile material insertion hole 12a can be divided along the surface along the axial direction.
[0029]
Further, as shown in FIG. 8, the pressure jig 13 is a member having a length substantially equal to the outer diameter of the partition wall 12 and having a width smaller than the inner diameter of the existing pipe 1. A tensile material attachment hole 13a is formed at a position corresponding to the insertion hole 12a. These ring materials 11, 12 and 13 are formed of a material having an appropriate strength, such as a steel material.
[0030]
In this embodiment, these ring members 11, 12, 13 are brought into the space S in front of the removed portion in a divided state and assembled in the front space S as shown in the figure. That is, when an operator enters both the removal portion 1b and the remaining portion 1a, after the partition wall 12 and the ring material 11 are completely assembled, the tension member 14 is moved from the removal portion 1b side to the remaining portion 1a side. The pressure jig 13 is connected to the tension member 14 on the remaining portion 1a side.
[0031]
Further, when assembling the pressure bearing body 10 only from the removal portion 1 b side, the tension member 14 is passed through the mounting hole 13 a of the pressure jig 13, and the nut protruding to the front side of the pressure jig 13 And the tension member 14 is connected to the pressure jig 13. Before and after this, only the lower half of the partition wall 12 is assembled, and the tension member 14 is disposed in the insertion hole forming groove exposed on the upper surface thereof. When the insertion hole 12a is formed at a position where it cannot be divided, the tension member 14 is passed through the insertion hole 12a and then connected to the pressure jig 13 in front of the partition wall. Thereafter, the upper half of the partition wall 12 is assembled, and then the ring material 11 is assembled on the rear side of the partition wall 12.
[0032]
Moreover, in this embodiment, the back injection pipe | tube 20 is connected to the injection hole 12b of the partition 12 after an appropriate step, for example, assembly of a support body. The base end of the backfill injection pipe 20 is connected to the backfill material injection plant 21.
[0033]
Thus, as shown in FIGS. 4 and 5, the supporting member 10 is disposed so as to contact substantially the entire annular tip surface of the removal portion 1 b, and the tension member 14 engaged and connected to the supporting member 10. Is extended into the shaft 2.
[0034]
(Propulsion equipment change process)
The propulsion direction of the propulsion equipment 4 is changed to the opposite direction as shown in FIG. 9 in parallel with or before and after the installation of the pressure bearing body 10. That is, in the case of this embodiment, the direction of the propulsion jacks 7 and 7 is changed to the drawing direction so that the reaction force is applied to the reaction force wall 5f of the shaft front wall, and the base end portion of the tension member 14 is It connects with the front-end | tip part of the propulsion jacks 7 and 7.
[0035]
(Drawing and removing process)
If the above preparatory steps are completed, then, as shown in FIG. 9, the process proceeds to the removal step of the removed portion 1b. That is, the propulsion jacks 7 and 7 are extended, and the removal portion 1 b is pulled out into the shaft 2 through the tension member 14 and the support body 10. Since the space of the vertical shaft 2 is limited, if the removal portion 1b is pulled out for a predetermined length (for example, one stroke of the jack), the extraction portion 1c is cut and removed outside the vertical shaft 2 (see FIG. 10). . At this time, the length of the tension member 14 is adjusted according to the stroke length of the jacks 7 and 7. As described above, when the plurality of tension member units 14a are connected via the connecting member 14b, the base end side unit 14a is removed and then connected to the propulsion jacks 7 and 7 anew. From this point of view, it is desirable to set the length of the tensile material unit 14a in consideration of the fixed length of the drawn tube as the length of the one-time removal portion 1b. That is, it is desirable to consider the fixed length of the extraction pipe for the space of the vertical shaft 2, and it is desirable to pull out a predetermined length while holding the spacer as an insufficient stroke length of the jacks 7 and 7.
[0036]
On the other hand, when only such extraction is performed, a portion where the existing pipe 1 is extracted becomes a cavity, which may cause ground subsidence. Therefore, in order to prevent this, the above-described backfill injection pipe 20 and injection plant 21 are used, and the cement milk is added to the space SS in front of the removal portion formed along with the extraction according to the increase of the space SS. It is desirable to sequentially inject the backing material C such as. In this case, prior to injection, a backing material inflow preventing partition wall (cover material) (not shown) is attached to the end of the removed portion 1a on the removed portion side.
[0037]
Thus, when the drawing is completed as shown in FIG. 10, the shaft 2 is backfilled as necessary as shown in FIG. 11 to complete the construction. A symbol R indicates a backfill portion.
[0038]
(Other)
(B) In the above embodiment, the shaft 2 is formed using the manhole M. However, the present invention is not limited to the presence or absence of the manhole M, and the shaft is formed at a position where there is no manhole. good. Further, the shaft 2 needs to be formed at the base end portion of the removal portion 1b. However, if the shaft 2 is provided at another portion, for example, the distal end portion or the remaining portion 1a of the removal portion 1b, the installation of the pressure bearing body 10 is easy. There are advantages such as becoming.
[0039]
(B) Friction reduction processing includes, in addition to the lubricant injection described in the above embodiment, processing for disturbing the surrounding ground of the removal portion 1b by liquid injection to make it relaxed, processing for boring the surrounding ground of the removal portion 1b, etc. Can also be employed, or a combination of these processes.
[0040]
(C) In order to satisfy both the restraining force of the surrounding ground G and the ease of work, the friction reduction treatment is performed not only on the upper side of the removed portion 1b, but only on the upper side as well as on the sides as necessary. However, it may be applied to other parts or the whole. An example of the drilling position P when boring is shown in FIG.
[0041]
(D) The range in the axial direction of the tube in which the friction reduction process is performed can be determined as appropriate, and it is preferable to cover substantially the entire removal portion 1b. However, a part, for example, a range of more than half is effective.
[0042]
(E) It is sufficient that the friction reduction process is performed prior to the drawing process. Therefore, it is not necessary to push in following the friction reducing process such as injection of the lubricant as in the above example, and other processes can be performed between them.
[0043]
(F) Needless to say, the distal end surface of the removed portion 1b is clean so that it is substantially flat and orthogonal to the tube axis, that is, as much as possible so that the bearing member is in good balance. It is preferable to remove the chip and smooth the surface using a grinder if necessary. In addition, when dividing the removal portion as described above, the end surfaces of the divided portions are also smoothed so that the thrust or pulling force is transmitted in a balanced manner between the adjacent divided portions, and between the divided portions as necessary. It is desirable to interpose appropriate metal fittings.
[0044]
【The invention's effect】
As described above, according to the present invention, the existing pipe can be easily pulled out, and the risk of breakage of the existing pipe due to the drawing is reduced.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing a shaft forming process.
FIG. 2 is a schematic sectional view showing a friction reducing process.
FIG. 3 is a schematic cross-sectional view showing a propulsion equipment installation process.
FIG. 4 is a schematic cross-sectional view showing a pressure bearing body installation step.
FIG. 5 is an assembly view of a support body.
FIG. 6 is a front view of a ring material.
FIG. 7 is a front view of a partition wall.
FIG. 8 is a diagram of a pressure jig.
FIG. 9 is a schematic sectional view showing a drawing process.
FIG. 10 is a schematic sectional view showing a drawing process.
FIG. 11 is a schematic sectional view showing a construction completion state.
FIG. 12 is a schematic cross-sectional view showing a boring position.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Existing pipe, 1a ... Remaining part, 1b ... Removal part, 2 ... Vertical shaft, 10 ... Supporting body.

Claims (4)

When removing the existing pipe buried in the ground, the existing pipe is formed without forming a shaft that reaches the proximal end of the removed part of the existing pipe and that reaches the distal end of the removed part of the existing pipe. In the method of separating and removing the removed portion and the remaining portion, pulling the removed portion into the shaft and removing it,
A ring material that can be divided into a plurality of divided units that can pass through the existing pipe is brought into the space in front of the distal end portion of the removed portion through the existing pipe in a state of being divided into the divided units,
A disc-shaped partition wall that can be divided into a plurality of divided units that can pass through the existing pipe is brought into the space in front of the tip of the removed portion through the existing pipe in a state of being divided into the divided units,
A tensile member is inserted from the removed portion side of the partition wall to the remaining portion side, and a pressure jig that is a member having a width smaller than the inner diameter of the existing pipe is connected to the remaining portion side. ,
Assembling the ring material and the partition,
Wherein engaging the pressing jig in the partition wall, a state in which the partition wall in contact disposed at the distal end surface of the ring member, and contact disposed substantially throughout the annular distal end surface of the removed portion of disconnecting said ring member Then, withdrawing and removing the removed portion into the shaft through the tensile material ,
A method for pulling out and removing existing pipes buried in the ground characterized by this. The partition wall is provided with a back-injection hole, and in the space in front of the removal part formed as the removal part is pulled out, the back-in injection hole is inserted through the back-injection hole as the space increases. The method for extracting and removing an existing pipe buried in the ground according to claim 1, wherein the materials are sequentially injected . Prior to the extraction step, the friction between the removed portion and the surrounding ground ,
A process of injecting a lubricant into the ground around the removed portion;
Processing to disturb and relax the surrounding ground of the removed portion by liquid jet; and
A process of boring the surrounding ground of the removed part,
The method of pulling out and removing an existing pipe embedded in the ground according to any one of claims 1 to 3, which is reduced by performing at least one treatment . In reducing the friction, at least the tip portion of the removed portion is removed by a predetermined pushing length, and the removed portion is pushed in with the friction reducing process, and the friction between the removed portion and the surrounding ground. The method of pulling out and removing existing pipes embedded in the ground according to claim 3, wherein

Images