JP6749740B2 - Drain pipe laying method - Google Patents

Description

The present invention relates to a drain pipe laying method which can be applied to a groundwater level lowering method mainly based on a water pipe system.

The groundwater level lowering method is known as one of the technologies for preventing ground liquefaction. In the case of the ground improved by this construction method, the thickness of the non-liquefied layer in the shallow layer from which groundwater has escaped increases, and the effective loading pressure increases above the groundwater level, making it difficult to liquefy. Therefore, the groundwater level lowering method can be a highly effective liquefaction countermeasure depending on the ground conditions. Above all, the method of lowering the groundwater level by the drainage pipe method can be easily applied to the framework of integrated liquefaction measures for public facilities and residential land, because it can be applied to roads and residential land without distinction.

In the case of the above-mentioned drainage pipe method of the groundwater level lowering method, a porous drain pipe having water permeability is buried in a predetermined section of the ground to be constructed in a substantially horizontal state or in a gently sloping state. A drain pipe (also called a drain pipe) buried in the ground lowers the groundwater level of the target ground to the required level by collecting rainwater and spring water in the ground and discharging it. This makes the ground after construction hard to liquefy.

Regarding the groundwater level lowering construction method using the drainage pipe method, the prior arts disclosed in Patent Documents 1 to 6 below already exist. The outlines of these are as follows.
[Patent Document 1]
In the case of the technique of this document, a hollow net pipe formed by weaving a plastic thin wire into a cylindrical shape is buried in the ground as a drain pipe. The document describes a method in which a casing is vertically erected in the ground for drilling, a drain material is inserted into the casing, and then the casing is pulled out to leave the drain material in the ground. ing.
[Patent Document 2]
In the case of the technique of this document, a hollow cylindrical drainage material in which linear synthetic resins are stacked is buried as a drain pipe in the ground. This Patent Document 2 also describes a construction method similar to that of Patent Document 1. At that time, Patent Document 2 also describes that the drainage material described above is added to a predetermined length by a synthetic resin joint.
[Regarding Patent Document 3]
In this technique, a mesh-shaped resin pipe made of a hard synthetic resin, which is formed by melting and extruding a plurality of thread-like strands in a spiral shape into a tubular shape, is buried in the ground as a drain pipe.
[Patent Document 4]
In the case of the technique of this document, a waste water treatment material made of hard synthetic resin, which is formed by depositing a large number of monofilaments in a random loop shape, is buried in the ground.
[Patent Document 5]
In the case of the technique of this document, a three-dimensional net-like structure on a flat plate in which linear objects made of a random spiral thermoplastic synthetic resin are point-bonded is buried in the ground.
[Patent Document 6]
In the case of the technique of this document, a plastic pipe having an annular unevenness such as a corrugated pipe is described, and the annular ridge is fitted into a groove formed on the outer periphery of the sheath pipe to connect the resin pipes on both sides. The structure is described.

It is said that it is desirable to bury the above-mentioned drain pipe in a substantially horizontal state or in a gently inclined state with respect to the ground, from the viewpoint of improving water collection efficiency over a wide range. As one of the construction methods in that case, a construction method (excavation construction method) for excavating the ground to be buried in the drain pipe is widely practiced.

The well-known excavation method has the following outline. In the preceding step of the excavation method, by excavating the ground from the surface side toward the ground, a drain pipe burying groove wider than the diameter of the drain pipe is formed with a length reaching the entire length of the drain pipe. In the next step of the excavation method, the drain pipe is placed in the drain pipe burying groove. After that, the trench for burying the drain pipe is covered with quarry or the soil is backfilled.

Regarding the above-mentioned excavation method, the following points have been pointed out as technical problems. One of them is that the underground is dug up from the surface side, which makes it difficult to construct in urban areas with many structures and existing buried objects and roads with heavy traffic. The other is that the treatment of a large amount of earth and sand generated by excavation is troublesome. The other one is that the construction cost is high due to the need for large-scale excavation work. The other one is that there is no approach or contact to the buried drain pipe except for ground excavation, which makes maintenance of the equipment difficult after the drain pipe is buried.

The construction method disclosed in the following Patent Document 7 is made in order to solve the above-mentioned technical problem found in the excavation construction method. In the case of this document technique, the following characteristic points are given as the reason why the problems of the prior art are solved. The first feature is to insert and bury the drain pipe from the starting shaft to the reaching shaft. In this case, since the ground is not excavated from the ground side, it will be possible to bury the drain pipe in urban areas and roads relatively easily. The second feature is that the required vertical and horizontal shaft space volume is small. As a result, the total volume of excavation, including the excavation of the side shaft, is reduced, so that the cost required for treating the excavated soil can be reduced and the construction cost can also be kept low. The third feature is that the starting shaft and the reaching shaft connected by the drain pipe can be effectively used as a primary storage tank for the underground accumulated water (drain) removed from the soil. Of course, by using these vertical shafts, the drain pipes can be easily cleaned and inspected, and the drainage pumps and the like arranged in the vertical shafts can be easily maintained and managed.

However, the construction method of Patent Document 7 still has technical problems to be improved. It is related to the removal of the propulsion pipe left in the shaft. By the way, for the remaining propulsion pipe in the horizontal shaft, it is common to apply a pushing force from the starting vertical shaft side toward the reaching vertical shaft side and pull out from the reaching vertical shaft side. Regarding this, it would be good if the propulsion pipe could be pushed out of the horizontal shaft by using the drain pipe when inserting it into the horizontal shaft from the starting vertical shaft side toward the reaching vertical shaft side, but it is possible to remove it with a porous shape made of plastic etc. The drain pipe consisting of the above pipe does not have sufficient mechanical properties to withstand the removal of the propulsion pipe. If the drain pipe is intentionally used for removing the propulsion pipe, damage to the drain pipe cannot be avoided.

Regarding the removal of the above-mentioned propulsion pipe, the construction method of Patent Document 7 uses a high-strength metal pipe called a sheath pipe to perform this. That is, the metal sheath tube is pushed into the horizontal shaft from the starting vertical shaft side toward the reaching vertical shaft side, and the propulsion pipe is pushed out of the horizontal shaft through the push-inserted sheath pipe to be removed. Regarding this, at the stage where all the propulsion pipes have been pushed out of the horizontal shaft and removed, the sheath pipe has been inserted and laid from one end (starting vertical shaft side) to the other end (reaching vertical shaft side) of the horizontal shaft. Regarding this, it can be said that the propulsion pipe was placed in the horizontal shaft in exchange with the sheath pipe. After that, the drain pipe is laid down from one end to the other end in the sheath pipe by pushing and inserting the drain pipe into the sheath pipe. In such a case, the drain pipe is not directly laid inside the shaft, but is indirectly laid inside the shaft through the inside of the sheath pipe. After this, the sheath pipe is removed from the inside of the side shaft to the outside of the side shaft, so that only the drain pipe is left inside the side shaft.

In the above construction method of Patent Document 7, two steps are required for laying the drain pipe in the horizontal shaft, such as laying the sheath pipe in the horizontal shaft and then laying the drain pipe in the sheath pipe. In the case of laying a drain pipe with two steps, naturally, more labor, labor, and time are spent compared to a simple one-step work, which causes a delay in construction and an increase in construction cost. ..

In addition, in the above-mentioned construction method of Patent Document 7, technical consideration is required also when inserting and interposing the drain pipe in the sheath pipe. This is because the drain pipe is clogged with mud and frictional resistance is generated between the drain pipe and the sheath pipe during the insertion. As a countermeasure against this, in the construction method of Patent Document 7, a special grease is applied to the outer peripheral surface of the drain pipe to reduce the above frictional resistance.

However, in the case of the above clogging prevention measures and friction mitigation measures, the cost and labor increase due to the fact that special grease is required and a lot of labor is required to apply this grease, which also has the effect of extending the construction period. Occurs.

JP, 2008-144558, A JP 2004-100185 A JP, 2002-364785, A JP, 2002-275876, A JP 2001-055719 A JP 2007-064457 A JP, 2017-002641, A

The present invention has been made in order to solve the above problems, and its purpose is to provide a drain pipe laying that is safe, accurate, and easy to construct, shortening the laying construction period, reducing the laying construction cost, etc. It is intended to provide a drain pipe laying method that can be measured.

The drain pipe laying method according to the present invention is characterized by the technical contents described in the following items 1 to 5 as means for solving the problems for achieving the intended purpose.
<Item 1>
A drain pipe with water permeability is laid in the underground shaft that penetrates the starting shaft and the reaching shaft from the surface side to the vertical direction in the ground in the horizontal direction to connect the compatible shaft to each other. In the construction method for
When laying a composite pipe in which the drain pipe is installed inside a protection pipe for protecting the drain pipe over the entire length of the shaft, the starting shaft is located at one end of the shaft at the reaching shaft side. Pushing in and inserting the composite pipe toward the other end of the shaft, and
Laying the drain pipe from one end to the other end of the shaft by repeating pushing of the composite pipe into the shaft, and
The drain pipe laying method characterized by.
<Item 2>
In the drain pipe laying method according to claim 1,
A drain pipe laying method, wherein when the propulsion pipe is left in the side shaft, the propulsion pipe is discharged from the inside of the side shaft to the reaching vertical shaft side and removed through the compound pipe pushed in and inserted.
<Section 3>
In the drain pipe laying construction method described in the first item or the second item,
A drain pipe laying method, characterized in that a protective member is applied to a rear end surface of the composite pipe when the composite pipe is pushed and inserted into the horizontal shaft, and the pushing insertion force applied to the protective member is transmitted to the composite pipe.
<Item 4>
In the underground shaft which penetrates horizontally between the starting shaft and the reaching shaft going from the surface side to the vertical direction in the underground and making the compatible shaft in communication with each other, and in the protection pipe for protecting the drain pipe, Regarding the relative relationship with the composite pipe in which the drain pipe is installed, the composite pipe is laid from one end to the other end of the horizontal shaft, and
In the construction method on the premise that the protection pipe of the composite pipe is removed from the inside of the shaft and the drain pipe is left in the shaft,
The drain laying method, characterized in that after the drain pipe is held in the horizontal shaft so that the drain pipe stays in the horizontal shaft, the protection pipe is pulled out from the horizontal shaft to the starting vertical shaft side or the reaching vertical shaft side. ..
<Section 5>
A drain pipe with water permeability is laid in the underground shaft that penetrates the starting shaft and the reaching shaft from the surface side to the vertical direction in the ground in the horizontal direction to connect the compatible shaft to each other. In the construction method for
When laying a composite pipe in which the drain pipe is installed inside a protection pipe for protecting the drain pipe over the entire length of the shaft, the starting shaft is located at one end of the shaft at the reaching shaft side. Pushing in and inserting the composite pipe toward the other end of the shaft, and
Laying the drain pipe from one end to the other end of the shaft by repeating pushing of the composite pipe into the shaft, and
Drain pipe laying, characterized in that after holding the drain pipe in the horizontal shaft stop state so that the drain pipe remains in the horizontal shaft, the protection pipe is pulled out from the horizontal shaft to the starting vertical shaft side or the reaching vertical shaft side. Construction method.

The drain pipe laying method according to the present invention has the following useful and beneficial effects.
[Effect 1: Safety and accuracy of construction]
When the drain pipe is laid in the shaft in the method of the present invention, the drain pipe is internally installed in the protective pipe to form a composite pipe of these two pipes, and the composite pipe is pushed and inserted in the shaft. That is, the drain pipe and the protection pipe are simultaneously inserted into the shaft. In addition, in such a case, the protective tube that is not insufficient in strength mainly receives the tube insertion force (also referred to as the tube propulsion force or the tube pushing force), so make sure that the drain tube is not deformed, damaged, or damaged. Unreasonable force does not work. Therefore, the drain pipe is accurately inserted and laid in the shaft while being protected by the protection pipe. Of course, at this time, it is difficult for the drain pipe that is in an appropriate protective state through the protective pipe to be damaged or collapse. Therefore, the safety of this construction can be expected.
[Effect 2: Ease of construction]
In the case of the method of the present invention, it is said that two pipes, a drain pipe and a protection pipe, are inserted into the horizontal shaft, but since both pipes are polymerized inside and outside to form one cohesive composite pipe, one pipe This tube insertion can be carried out by the same means and labor as those for inserting in the side shaft. Therefore, the construction work for inserting and laying the two pipes (composite pipes) into the horizontal shaft can be easily performed.
[Effect 3: Shortening the construction period]
When using the existing conventional method, the drain pipe is laid in the horizontal shaft, such as the step of laying one pipe (sheath pipe) in the horizontal shaft in advance and the step of inserting the drain pipe into the horizontal pipe after that. Two steps are required to complete. On the other hand, in the case of laying the drain pipe in the horizontal shaft by the method of the present invention, only one composite pipe (drain pipe and protection pipe) is inserted in the horizontal shaft, so the drain pipe laying in the horizontal shaft is one step. OK. Therefore, in the case of the method of the present invention, the pipe laying period can be shortened by the amount of the work corresponding to one step being omitted.
[Effect 4: Reduction of installation labor]
The laying of the drain pipe in the shaft by the method of the present invention requires only one step of inserting the composite pipe in the shaft, as compared with the existing conventional method (the number of steps = 2). That is, in the case of the method of the present invention, since the work corresponding to one step is omitted, the labor for laying the target pipe can be reduced by one step.
[Effect 5: Reduction of installation costs]
As described above, according to the method of the present invention, the target pipe laying is performed in one step, so that the construction cost can be reduced.
[Effect 6: Reduction of construction costs and shortening of construction period]
One pipe (sheath pipe) is laid in the shaft in advance, and then the drain pipe is inserted into the sheath pipe. With the existing construction method, the drain pipe is prevented from being clogged when inserting the drain pipe into the sheath pipe. To reduce the friction between the drain pipe and the sheath pipe, a special agent must be applied to the drain pipe. On the other hand, in the case of the method of the present invention in which the composite pipe including the drain pipe and the protection pipe is inserted into the shaft, the protection pipe prevents clogging of the drain pipe, and there is room for friction between the pipes in the composite pipe. But it's hard to see. Therefore, in the case of the method of the present invention that does not have this kind of trouble, the special agent as found in the existing conventional method is not necessary, and the laying work cost can be reduced even by not applying the special agent. it can. In addition, the absence of the application of the special agent leads to the shortening of the construction period by the construction method of the present invention.
[Effect 7: Reliable drain pipe remains in the shaft]
Among the two pipes (composite pipes) laid inside the horizontal shaft in the method of the present invention, the drain pipe is retained in the horizontal shaft and only the protective pipe is pulled out from the horizontal shaft to the vertical shaft side. In this way, when the drain pipe is held in the horizontal shaft and the protective pipe is pulled out from the horizontal shaft, the drain pipe can be reliably left in the horizontal shaft, and the intended drain pipe installation can be completed without problems.
[Effect 8: Improvement of layability of the composite pipe in the horizontal shaft]
In the method of the present invention, when the protective member is applied to the rear end surface of the composite pipe and the composite pipe is pushed in and inserted into the shaft while applying a force to the protective member, not only the damage prevention of the drain pipe but also the protective pipe Also, a sufficiently large insertion force can be applied to the entire composite pipe without damaging it. Therefore, in the case of the method of the present invention, the composite pipe can be smoothly, easily and surely laid in the shaft through the sufficiently large insertion force.
[Effect 9: Reduction of installation work cost and construction period]
When the propulsion pipe is left in the shaft, it can be removed by pushing the residual propulsion pipe from the shaft to the reaching shaft by using the composite pipe pushed into the shaft. Therefore, it is possible to reduce the laying construction cost and shorten the construction period even for the drain pipe laying under the condition that the propulsion pipe is left in the side shaft.

It is a longitudinal section showing roughly the 1st step in one embodiment of the construction method of the present invention. It is the longitudinal cross-sectional view and the top view which respectively showed the 2nd step in one Embodiment of this invention construction method. It is a longitudinal section showing roughly the 3rd step in one embodiment of the construction method of the present invention. It is the front view which partially cut open and showed the compound pipe used as the head side in one embodiment of the construction method of the present invention. It is the longitudinal cross-sectional view which briefly showed the 4th step in one embodiment of the construction method of this invention, and the longitudinal cross-sectional view of a bearing pipe. It is the longitudinal cross-sectional view which showed roughly the 5th step in one embodiment of the construction method of this invention, and the longitudinal cross-sectional view of a holding plate. It is a longitudinal section showing roughly the 6th step in one embodiment of the construction method of the present invention. It is the perspective view which showed the protection tube in this invention. It is the perspective view which showed the drain pipe in this invention. It is the perspective view which showed the connection part of the drain pipe in this invention. It is sectional drawing which showed the connection part of the drain pipe in this invention. It is an exploded perspective view showing a connecting outer pipe for a drain pipe in the present invention. It is the perspective view which showed the connection inner pipe for drain pipes in this invention. It is the front view which carried out the partial incision and was shown schematically about the composite pipe in this invention. It is an explanatory view showing roughly an example of mutual connection of compound pipes in the method of the present invention.

An embodiment of a drain pipe laying method according to the present invention will be described in detail with reference to the accompanying drawings.

The method of the present invention is a method for laying the drain pipe in the underground shaft. Each step performed at that time is illustrated in FIGS. 1 to 3 and 5 to 7.

In FIGS. 1 to 7, 11 is a starting shaft, 12 is a reaching shaft, 13 is a horizontal shaft, 21 is a propulsion pipe, 21 is a composite pipe, 41 is a drain pipe, 51 is a protection pipe, and 61 is an excavation pipe. , 62 is a hydraulic mechanism, and 63 is a propulsion jack of the hydraulic mechanism 62.

As is clear with reference to FIGS. 1 to 3 and FIGS. 5 to 7, the starting shaft 11 and the reaching shaft 12 direct two predetermined portions of the ground in the vertical direction, that is, from the surface side to the vertical direction in the ground. It is formed by excavating. For excavation of the compatible wells 11 and 12, as a typical example, a well-known mechanical excavation means by an excavation machine suitable for vertical excavation is adopted. In the case of the starting shaft 11 and the reaching shaft 12 thus excavated and formed, they face each other with a relative distance therebetween. By the way, a specific example of the compatible shafts 11 and 12 will be described by giving numerical values. The starting shaft 11 has a diameter within a range of 2 to 3 m and a depth from the ground of about 5.5 m. The reach shaft 12 has a diameter within a range of 1.5 to 2 m and a depth from the ground of about 5.5 m. Regarding the distance between the starting shaft 11 and the reaching shaft 12, the distance over the center lines of the compatible shafts 11 and 12 is about 20 m when the vertical center lines of the compatible shafts 11 and 12 are used as a reference. On the other hand, in the case of the horizontal shaft 13, this is formed by horizontally excavating a tunnel in the ground from the starting shaft 11 side (start point side) toward the reaching shaft 12 side (end point side).

The first step illustrated in FIG. 1 and the second step illustrated in FIG. 2 relate to excavation of the shaft 13. Hereinafter, the first step and the second step will be described with reference to FIG.

In FIG. 1, a well-known excavator 61 for carrying out, for example, a mud construction method is prepared in the starting shaft 11. A well-known excavation cutter, a water retention head, a screw conveyor, etc. are attached to or attached to the excavator 61. The excavator 61 is also called a propulsion machine. A well-known hydraulic mechanism 62 for pushing the excavator 61 and the propulsion pipe 21 into the horizontal shaft 13 is arranged in the starting shaft 11. The hydraulic mechanism 62 includes a reciprocating propulsion jack 63.

Here, the propulsion pipe 21 will be described in advance. The propulsion pipe 21 has a tubular shape such as a protective pipe 51 (see FIG. 8) having a male screw 52 and a female screw 53, and a male screw similar to the male screw 52 is formed on the outer peripheral surface of the tip thereof. Or, a female screw similar to the female screw 53 is formed on the inner peripheral surface of the rear end. The male screw and the female screw of the propulsion pipe 21 make a pair and can be screwed into each other. Therefore, in the case of the propulsion pipe 21, a large number of propulsion pipes can be lengthened by axially connecting them with a pair of male and female screws. Of course, the long propulsion pipe 21 by this screw connection has a series (one) tubular shape in which no step or the like is formed on the inner and outer peripheral surfaces of the connecting portion. Further, the propulsion pipe 21 can be connected to the rear end portion of the excavator 61 via a screw on the front end side thereof. The constituent material of the propulsion pipe 21 may be any material having a mechanical strength capable of withstanding a predetermined propulsive load, and may be, for example, metal (eg, steel) or plastic (eg, chloride). Vinyl), reinforced plastic, concrete, resin concrete, porcelain, etc. Incidentally, a typical propulsion tube 21 is made of steel. All of these matters regarding the propulsion pipe 21 are well known.

The reciprocating propulsion jack 63 of the hydraulic mechanism 62 illustrated in FIG. 1 moves forward (forward) toward the front peripheral surface of the starting shaft 11 or moves backward (backward) to the original position. It is a thing. As is well known, there are various sizes of the hydraulic mechanism 62 such as small size, medium size, and large size. The larger the hydraulic mechanism 62, the larger the capacity (output) and the larger the stroke of the propulsion jack 63. Of course, as the hydraulic mechanism 62, one having an appropriate size according to the construction scale and excavation conditions is adopted. In particular, taking into consideration the diameter of the starting shaft 11, etc., the hydraulic mechanism 62 having a size suitable for this is selected. As is well known, when the tunnel-shaped horizontal shaft 13 is formed by excavation, the propulsion pipe 21 is connected to the rear end of the leading shaft 61, and the shaft 61 increases as the length of the horizontal shaft 13 increases. The propulsion pipe 21 is additionally connected to the rear end of the rear pipe at appropriate times. In this case, the larger the hydraulic mechanism 62, the larger the “number of connected propulsion pipes per connection” connected to the rear end of the excavator 61 can be. Conversely, in the smallest hydraulic mechanism 62, the stroke of the propulsion jack 63 is such that one (one) propulsion pipe 21 or excavator 61 (single unit) can be pushed into the horizontal shaft 13. .. The propulsion pipes and the propulsion pipe 21 and the excavator 61 can be connected to each other in the front and rear by the above-described male screw and female screw formed on the inner and outer peripheral surfaces of the respective end portions.

Regarding the drain pipe laying work illustrated in Fig. 1 and Fig. 2, in the case of a small-scale work laying a small-diameter drain pipe in a relatively shallow ground, the diameter (diameter) of the starting shaft 11 also becomes small. .. In the construction work when the diameter of the starting shaft 11 is small, the hydraulic mechanism 62 of a small size or a medium size is inevitably adopted. In this case, the propulsion pipes 21 may be pushed into the horizontal shaft 13 either one by one or connected to each other. As a concrete example, first, the first propulsion pipe 21 is connected in series to the rear end of the excavator 61, and the first propulsion pipe 21 with the excavator 61 (primary excavation coupling body) is connected to the hydraulic mechanism 62. It is attached to the propulsion jack 63. As a result, the tip of the excavator 61 comes to face the front wall (front peripheral wall surface) of the starting shaft 11. After that, when the excavator 61 and the hydraulic mechanism 62 are in the operating state, the excavator 61 is in the underground excavation operating state, and the forward driving jack 63 of the hydraulic mechanism 62 starts the primary excavation coupling body from the vertical shaft. It will be pushed into the front wall of 11. That is, the excavator 61 continues to start the first excavation work from the front wall side of the starting shaft 11 toward the horizontal direction (toward the reaching shaft 12 side), whereby the excavator 61 and the first propulsion pipe are started. 21 enters the ground horizontally.

In the above, when the propulsion jack 63 of the hydraulic mechanism 62 reaches the end of the forward stroke, the excavator 61 finishes the first horizontal excavation work corresponding to the forward stroke. At this point, the machine 61 and the hydraulic mechanism 62 are temporarily stopped. Regarding the mechanical device and the excavation situation at this stage, the excavator 61 that has horizontally entered the ground forms a part of the shaft 13, and the first propulsion pipe 21 following the excavator 61 is also underground. Is approaching horizontally. On the other hand, the propulsion jack 63 of the hydraulic mechanism 62 moves back. That is, the propulsion jack 63 is disconnected from the rear end of the first propulsion pipe 21, enters the backward stroke, and returns to the original position. In this propelling jack returning state, a space where two propulsion pipes 21 can be interposed between the propulsion jack 63 (tip portion) and the first propulsion pipe 21 (rear end portion) that has horizontally entered the ground. Occurs.

When the first horizontal excavation work is completed, the two propulsion pipes are inserted between the first propulsion pipe 21 (rear end) and the propulsion jack 63 (front end) that have horizontally entered the ground, as described above. The above-mentioned space in which 21 can be interposed is generated. In this space, an additional second propulsion pipe 21 (two propulsion pipes 21 connected) is interposed. The second propulsion pipe 21 interposed between the predetermined portions will be described in detail. The tip end portion of the second propulsion pipe 21 is connected to the rear end portion of the first propulsion pipe 21 that has entered the horizontal underground state. The rearmost end portion of the second propulsion pipe 21 is mounted so as to abut the propulsion jack 63 of the hydraulic mechanism 62. The connection body such as the propulsion pipe thus increased is changed from the above-described primary excavation connection body to a secondary excavation connection body. After that, when the excavator 61 and the hydraulic mechanism 62 are in the re-operation state, the excavator 61 is reactivated, and the hydraulic mechanism 62 reaches the secondary excavation coupling body via the re-propulsion jack 63 to reach the vertical shaft 12 side. It will be pushed into. Therefore, the excavator 61 starts the second horizontal excavation work from the starting vertical shaft 11 side toward the reaching vertical shaft 12 side.

The excavator 61 in the second underground horizontal excavation also finishes the horizontal excavation work when the propulsion jack 63 of the hydraulic mechanism 62 reaches the end of the forward stroke. At the same time, the machine 61 and the hydraulic mechanism 62 are temporarily stopped. The horizontal shaft 13 at the stage where the second horizontal excavation work has been completed is in an obvious extension state due to an increase in the amount of underground horizontal excavation. The propulsion jack 63 is returned from the rear end of the connection propulsion pipe (horizontal horizontal plunge state) to the original position after entering the backward stroke. Also at this time, a space in which three propulsion pipes 21 can be interposed is formed between the rearmost end of the connection propulsion pipe and the front end of the propulsion jack.

When the second horizontal excavation work is completed, two propulsion pipes 21 are interposed between the rear end portion of the connecting propulsion pipe and the front end portion of the propulsion jack because the propulsion jack 63 enters the backward stroke. There is again a space available. In this space, as in the previous time, a new connected propulsion pipe (two additional propulsion pipes 21) is inserted again. In this way, the newly connected propulsion pipe interposed between the predetermined parts is connected to the rear end of the preceding connected propulsion pipe (horizontal underground thrust state), as in the previous time. The rear end of the newly connected propulsion pipe may be attached to the propulsion jack 63 of the hydraulic mechanism 62. The above-mentioned secondary excavation coupling body is now an extended third series coupling body. After that, when the machine 61 and the hydraulic mechanism 62 are restarted, the machine 61 is restarted, and the hydraulic mechanism 62 also reaches the machine 12 side via the forward-moving propulsion jack 63. It will be pushed further into. As a result, the excavator 61 starts the third horizontal excavation work from the starting shaft 11 side toward the reaching shaft 12 side.

The excavator 61 in the third underground horizontal excavation also finishes the horizontal excavation work when the propulsion jack 63 of the hydraulic mechanism 62 reaches the end of the forward stroke. At the same time, the machine 61 and the hydraulic mechanism 62 are temporarily stopped. The horizontal shaft 13 at the stage where the third horizontal excavation work has been completed is in the extension and extension state due to the increase in the underground horizontal excavation amount. The propulsion jack 63 also returns to its original position after entering the backward stroke after being disengaged from the rearmost end of the connection propulsion pipe (horizontal underground plunge state). Also at this time, a space where two propulsion pipes 21 can be interposed is formed between the rearmost end of the connected propulsion pipe and the front end of the propulsion jack.

After this, the fourth and subsequent underground horizontal excavation work is repeated the required number of times in the same manner as described above. As a result, the horizontal shaft 13 that penetrates the ground from the starting shaft 11 to the reaching shaft 12 is completed. Regarding this, referring to the first step of FIG. 1 and the second step of FIG. 2, the horizontal shaft 13 of the first step is in the process of being formed, and the horizontal shaft 13 of the second step is composed of the starting shaft 11 and the reaching shaft 12. It is in a completed state that penetrates the space. In the lateral shaft 13 thus formed, a large number of propulsion pipes 21 in a series of connected states are present (remain). However, as to the excavator 61 that rushes into the reaching shaft 12 at this stage, as shown in FIG. 2, after being disconnected from the propulsion pipe array (the propulsion pipe 21 at the head) and taken into the reaching shaft 12, , Is carried out from there to the ground side.

One of the main methods of laying a drain pipe according to the present invention is to lay a drain pipe internal protective pipe in which the drain pipe 41 is embedded in the protective pipe 51, that is, a composite pipe 31 as shown in FIG. Is. Therefore, the drain pipe 41 is laid inside the horizontal shaft 13 by laying a composite pipe inside the horizontal shaft 13. When such a drain pipe is laid, when the propulsion pipe 21 is left in the horizontal shaft 13, the propulsion pipe 21 may be discharged to the outside of the horizontal shaft 13. Another main feature of the drain pipe laying method according to the present invention is to hold the drain pipe 41 in the shaft 13 in a stopped state when the drain pipe 41 is installed in the shaft 13 together with the protection pipe 51. After that, the protective tube 51 is pulled out (taken out) from the side shaft 13 to the side of the starting shaft 11 or the side of the reaching shaft 12. Hereinafter, the protection tube 51, the drain tube 41, the composite tube 31, etc. will be described in advance, and then each step of the method of the present invention will be described.

The protection tube 51 illustrated in FIG. 8 has a circular cross section. The protection tube 51 has a diameter such that the drain tube 41 can be slidably installed inside the protection tube 51. In terms of material, the protective pipe 51 has mechanical characteristics (mechanical strength) that can withstand at least the pipe propulsion force (pipe insertion force into the shaft 13) by the propulsion jack 63 of the hydraulic mechanism 62. More specifically, the protective pipe 51 is made of metal (eg steel), plastic (eg vinyl chloride), reinforced plastic, concrete, like the propulsion pipe 21. Made of any material or material selected from these, such as those made of resin concrete, porcelain clay, composite materials (eg, composite material of metal and synthetic resin) .. A typical protective tube 51 is made of steel.

As is apparent from FIG. 8, a male screw 52 is formed on the outer peripheral surface of one end of the protective pipe 51, and a female screw 53 is formed on the inner peripheral surface of the other end of the protective pipe 51. .. In this case, the male screw 52 and the female screw 53 are paired so that they can be screwed into each other. In this case, in the two protection tubes 51, the male threads 52 of the one protection tube 51 and the female threads 53 of the other protection tube 51 can be screwed into each other to connect the two protection tubes 51 into a series of tubular shapes. You can do it. Therefore, in the case of the protective tube 51, it is possible to make the protective tube 51 long by connecting a large number thereof in this way.

The drain pipe 41 illustrated in FIG. 9 also has a circular cross section. The drain pipe 41 has water permeability. That is, the wall of the drain pipe 41 has water permeability. A typical example of the drain pipe 41 is a net-structured pipe made of a thermoplastic resin such as polypropylene. The reticulated structure tube can also be referred to as a reticulated structure tube. The net-like structure tube is formed by entwining strands (string-like material), and the contact points of the strands are joined together. Regarding specific dimensions, the length of the network tube is 1 m, the tube wall thickness of the network tube is about 180 mm, and the diameter of the strand is about 2 mm. By the way, the drain pipe 41 having the mesh structure has a compressive strength capable of withstanding a pressure of about 7 m in soil cover thickness.

In the embodiment of FIG. 9, the outer peripheral surface of the drain pipe 41 is covered with a water-permeable filter material 42, or the outer peripheral surface of the water-permeable filter material 42 is covered with a net body 43. The filter material 42 prevents the drain pipe 41, which is buried in the ground, from being prematurely clogged due to intrusion of sand or the like, and the net body 43 causes the tip end portion of the filter material 42 to be flipped up by friction with other pipe inner surfaces. It is to prevent it from being compressed. The filter material 42 is made of non-woven fabric as an example, and the net body 43 is made of hard resin as an example. Regarding the drain pipe 41, there is a drain pipe 41 in which the mesh body 43 is omitted, or in which both the filter material 42 and the mesh body 43 are omitted.

The drain pipe 41 can be made long by connecting (connecting) a large number of pipes in the longitudinal direction. A plurality of (two) annular recessed grooves 44 are formed at both ends of the drain wall of the drain pipe 41 to serve for connection thereof. In addition, an inner pipe made of a hard synthetic resin may be installed inside the drain pipe 41, for example. Of these, the annular groove 44 corresponds to the annular protrusion 46 of the connecting outer tube 45, which will be described later, so that it can be fitted therein. The inner pipe installed inside the drain pipe 41 is also used for connecting the drain pipes to each other, which will be described later.

The connection outer tube 45 for the drain tube illustrated in FIG. 12 will be described below. Each of the drain pipes 41 connected for lengthening is held so that the connecting end faces of the two drain pipes 41 are butted against each other and the two pipes are aligned. The connecting outer tube 45 mounted on the outer peripheral surface of the drain connecting portion is made of a hard synthetic resin that is difficult to be deformed, for example, and has a split type shape structure as shown in FIG. The connecting outer pipe 45 becomes a circular pipe when two split mold members each made of a half-circular pipe are combined, and becomes two half-circular pipes when the two split mold members are disassembled. At both ends of the outer wall of the connection outer pipe 45, annular protrusions 46 are formed so as to be freely fitted into the annular recesses 44 of the drain pipe 41.

As is clear with reference to FIGS. 10 and 11, the two drain pipes 41 are in a straight line when their connecting end faces are butted against each other. Regarding the connection outer pipe 45, two disassembled half pipes (split members) are attached to the outer peripheral surfaces of the connection portions of both drain pipes 41 in a butt state, and in this attachment state, the two half pipe pipes. The (split mold member) is in a circular tubular united state. At this time, the annular recessed groove 44 of the drain pipe 41 and the annular protrusion 46 of the connection outer pipe 45 are fitted to each other. Further, the annular protrusion 46 of the connected outer tube 45 in the mounted state is provided with a fastening band 47 made of metal or the like on the recessed portion of the outer peripheral surface thereof, and the fastening band 47 is fastened. Due to the tightening force via the tightening band 47, the connected outer tube 45 is held in a united mounted state, and at the same time, the drain tube 41 is held in a connected state. This connection work is performed on the ground as an example, and is performed in a shaft such as the starting shaft 11 as another example.

The connection inner pipe 48 for the drain pipe illustrated in FIG. 13 will be described below. The connection inner pipe 48 is made of, for example, a hard synthetic resin or metal that is difficult to deform. As shown in FIG. 13, a plurality of (approximately four) locking claws 49 distributed in the circumferential direction are provided on the outer peripheral surfaces of both ends of the connecting inner pipe 48. Incidentally, the locking claw 49 of the illustrated example is formed by protruding a part of the tube wall of the connecting inner tube 48 outward, and is provided with a slope inclined in a predetermined direction. Each of the locking claws 49 bites into the inner peripheral surface of the end of the drain pipe 41 when the connecting inner pipe 48 is inserted.

The connection inner pipe 48 is inserted and inserted into the rear end portion of the drain pipe 41 for about 1/2 length. Therefore, the connection inner pipe 48 is exposed to the outside from the rear end side of the drain pipe 41 by about ½ length. This work is performed on the ground as an example, and is performed in the starting shaft 11 as another example. More specifically, regarding the connection between the drain pipes by the connection inner pipe 48, the connection inner pipe 48 capable of biting and fixing on the inner peripheral surface of the drain pipe 41 via the locking claw 49 is the drain pipe 41. It is pre-fitted and inserted into the rear end portion. When the two drain pipes 41 are connected to each other, about half the length of the connection inner pipe 48 exposed from the rear end of the one drain pipe 41 to the outside thereof is removed from the inside of the other end of the drain pipe 41. It is fitted and inserted into the inside. The connection between the drain pipes by the connection inner pipe 48 is performed prior to the connection between the drain pipes by the connection outer pipe 45.

There are several patterns for connecting the drain tubes to each other. One of them is a connection mode in which the connecting outer tube 45 and the fastening band 47 are used. In this case, the connection by the connection inner pipe 48 is not performed. The other one is a connection mode in which the connection inner pipe 48 is used. In this case, the outer connecting pipe 45 and the fastening band 47 are not connected. Still another one is a connection mode in which the connection outer pipe 45 and the fastening band 47 are used and the connection inner pipe 48 is also used. Which connection pattern to use is decided in consideration of various circumstances related to construction.

The above-mentioned connecting outer tube 45 can be referred to as a connecting outer tube, a connecting outer tube, and a connecting outer tube. As for the above connecting inner tube 48, this can be referred to as a connecting inner tube, a connecting inner tube, and a connecting inner tube. It can be called like an inner cylinder.

Regarding the composite pipe 31 of the present invention, as is clear with reference to FIG. 14, the drain pipe 41 having a relatively small diameter and the protection pipe 51 having a relatively large diameter are relatively fitted to each other. It is a combination of. Of course, in the case of both pipes 41 and 51, the outer diameter of the drain pipe 41 as the inner pipe is smaller than the inner diameter of the protection pipe 51 as the outer pipe, but the difference between the inner and outer diameters thereof is small. Further, the difference between the inner and outer diameters is such that a minute gap is generated between the outer peripheral surface of the drain pipe and the inner peripheral surface of the protective pipe. The presence of such a minute gap between the two pipes 41 and 51 forming the composite pipe 31 allows the drain pipe 41 and the protective pipe 51 to slide relative to each other in the axial direction.

In the case of the composite pipe 31 in which the drain pipe (inner pipe) 41 and the protection pipe (outer pipe) 51 are combined inside and outside so as to be slidable (sliding) in the axial direction, after the connection end portion of the drain pipe 41. The composite pipes can be connected to each other in a state where the end portion (or the front end portion) projects outward from the rear end portion (or the front end portion) of the protective pipe 51. The connection between the composite pipes as used herein means two types of pipe connection, such as a connection between the drain pipes and a protection pipe 51, which are components of the composite pipe 31, such as a connection between the drain pipes and a connection between the protection pipes. Means that.

The connection of the composite pipe 31 as described above is performed by the following procedure as an example. This will be described with reference to FIGS. First, as shown in FIG. 15A, the rear end portion (connection end portion) of one drain pipe 41 and the front end portion (connection end portion) of the other drain pipe 41 are butted against each other. That is, the two front and rear drain pipes 41 are abutted so as to be aligned in the axial direction in a straight line state (series state). As shown in FIG. 15B, the split outer connecting pipe 45 is applied to the abutting portion of both drain pipes 41 over the outer peripheral portion thereof. A fastening band 47 is applied to the annular convex portion 47 of the outer connecting pipe 45, and the fastening band 47 is fixed in a tightened state. The two front and rear drain pipes 41 arranged in the axial direction in the butted state are brought into a stable connected state by the fastening force of the fastening band 47. After that, as shown in FIG. 15C, the outer periphery of the drain pipe 41 on the rear side is covered with the protective pipe 51, and the rear protective pipe 51 and the front protective pipe 51 are connected to each other by these male screws. 52 and female threads 53 are screwed together (connected). Thus, the two front and rear drain pipes and the front and rear two protection pipes connected to each other correspond to the front and rear two composite pipes connected to each other. Therefore, it can be said that the composite connection of different kinds of pipes as shown in FIG. 15C is one in which the front and rear composite pipes 31 are connected.

In the method of the present invention, as described later, the composite pipe 31 is added in the axial direction and pushed (propulsed) into the shaft 13. The hydraulic mechanism 62 described above is used for this pushing. As is well known, the propulsion jack 63 of the hydraulic mechanism 62 includes a propulsion base 64 and a reaction force wall (pressure bearing wall) 65 provided at the rear end of the propulsion base 64. Regarding the propulsion jack 63, since the upper surface of the propulsion base 64 has a shape structure corresponding to the lower half of the composite pipe 31, the lower half of the composite pipe 31 on the upper surface side of the propulsion base 64. You can support it. In the propulsion jack 63, the front surface of the reaction wall 65 to which a pressing wheel or a pressing plate is attached is the same as the rear end surface of the composite pipe 31 (the rear end face of the drain pipe 41 or the rear end face of the protective pipe 41). Correspond. Therefore, in the case of the propulsion jack 63, the composite pipe 31 can be pushed in from the rear end face side on the front face side of the reaction force wall 65. Therefore, the lower half portion of the composite pipe 31 when it is pushed into the horizontal shaft 13 by the propulsion jack 63 is supported and supported by the propulsion base 64, and the rear end face thereof is directed to the front face portion of the reaction force wall 65.

Furthermore, in this state, the pushing force by the propulsion jack 63 acts on the drain pipe 41 and the protection pipe 51 in a predetermined manner. More specifically, it means that the protection pipe 51, which is superior in compressive strength, receives a large amount of pushing force of the propulsion jack from the front surface of the reaction wall, and the drain pipe 41 acts only with a light pushing force to the extent that it can enter the shaft 13. I don't. Therefore, in the case of the drain pipe 41, the pushing force of the propulsion jack 63 does not cause deformation or the like.

In the case of the composite pipe 31 that is pushed in and pressurized by the propulsion jack 63 as described above, the drain pipe 41 and the protective pipe 51, which are the components thereof, are protected, and the holding state by the propulsion jack 63 is stabilized. For the purpose, an attachment for connecting the rear end surface of the composite pipe 31 and the front surface of the reaction force wall 65 may be attached. For example, a bearing pipe 67 schematically shown in FIGS. 3 and 5 is interposed between the composite pipe 31 and the reaction wall 65. The pressure support pipe 67 is a member in which a circular substrate 68 and a cylindrical short pipe 69 are integrally formed, and the short pipe 69 projects from the front surface side of the substrate 68. Incidentally, the substrate 68 of the bearing pipe 67 can push the rear end surface of the drain pipe 41 in the composite pipe 31. Since the diameter of the short pipe 69 of the pressure bearing pipe 67 is substantially the same as that of the protection pipe 51, the rear end surface of the protection pipe 51 can be pushed by the front end surface of the short pipe 69. As means for mounting the pressure bearing pipe 67 over both the composite pipe 31 and the reaction force wall 65 (pressing portion 66), there are a male screw and a female screw as described above, a well-known fastener (bolt), and the like. Appropriate means are employed. In addition, a connection pipe (the same as the connection pipe 22 to be described later) and attachments such as the pressing ring and the pressing plate may be interposed and fixed between the both 31 and 65, if necessary. As this kind of attachment, a material made of a robust material, a material having elasticity or cushioning (buffering), a semi-rigid material, or the like is used depending on the situation. They are soft or semi-rigid plastics or composites of plastics and other materials (eg metals).

Next, with respect to the steps related to the main part of the construction method of the present invention, the third step illustrated in FIG. 3 and the fourth step illustrated in FIG. 5 will be described.

In the third step of FIG. 3, a large number of composite pipes 31 are inserted in the horizontal shaft 13 in a row (in a straight line). Regarding the composite pipes 31 in the horizontal shaft 13, the drain pipes as inner pipes and the protection pipes as outer pipes are connected to each other. As shown in FIG. 4, the composite pipe 31 located at the top of the drain pipe 41 has a tapered taper-shaped cover 32 made of a soft or semi-hard elastically deformable material (rubber or synthetic resin). The outer peripheral surface of the tip portion covers the outer peripheral surface of the tip portion of the protective tube 51. The inner peripheral surface of the front end of the cover 32 fits closely to the outer peripheral surface of the drain pipe 41, and the rear end of the cover 32 is fixed to the protective pipe 51 with, for example, a metal fastening band 33 or a screw 34. The cover 32 is functionally a packing. The cover 32 as a packing mainly prevents foreign matter such as earth and sand from entering the gap between the composite pipe 31 (between the outer peripheral surface of the drain pipe tip and the inner peripheral surface of the protective pipe tip). In addition to this, the array of propulsion pipes 21 in a row in the horizontal shaft 13 and the composite pipe 31 pushed into the horizontal shaft 13 are connected to their boundaries as schematically shown in FIG. Tube 22 may be interposed if desired. The connecting pipe 22 has a short tubular shape similar to the propulsion pipe 21. Similar to the propulsion pipe 21, the connection pipe 22 may have male and female screws for pipe connection at both ends. The connecting pipe 22 is connected to the rear end portion of the propulsion pipe 21 (the pipe on the side of the starting shaft 11) at the end of the propulsion pipe array with the excavator when the composite pipe 31 is pushed into the horizontal shaft 13.

In the following description of the third step of FIG. 3, for convenience of description, the composite pipe 31 with the cover 32 that is first pushed into the shaft 13 is referred to as the first composite pipe 31, and the second and third The composite pipes 31 inserted into the horizontal shaft 13 in the order of the fourth... are referred to as the second composite pipe 31, the third composite pipe 31, and the fourth composite pipe 31, respectively. For convenience of description, the drain pipes 41 and the protection pipes 51, which are the constituent elements of the first composite pipe 31, the second composite pipe 31, the third composite pipe 31, the fourth composite pipe 31, etc. The pipe 41, the second drain pipe 41, the third drain pipe 41, the fourth drain pipe 41,..., and the first protective pipe 51, the second protective pipe 51, the third protective pipe 51, and the fourth protective pipe 51. ...Is called.

In the case of the third step shown in FIG. 3, first, the first composite pipe 31 is pushed into the shaft 13. That is, the front end face of the first composite pipe 31 is applied to the rear end face of the rearmost propulsion pipe 21 projecting out of the horizontal shaft 13 in the starting shaft 11 that has completed the second step (Fig. 2 ), and that is the hydraulic pressure. It is pushed into the shaft 13 via the propulsion jack 63 of the mechanism 62. More specifically, after the pressure bearing pipe 67 is fixedly interposed between the rear end face of the first composite pipe and the front side of the propulsion jack, the first protection pipe is used as a synchronous (simultaneous) pushing operation by the propulsion jack 63. Since the 51 and the first drain pipe 41 are pushed in, the first composite pipe 31 enters the horizontal shaft 13. At this time, the propulsion pipe array with excavators (the excavators 61 in a row and the propulsion pipes 21) in the horizontal shaft 13 arrives at the vertical shaft 12 side by the first protection pipe 51 entering the horizontal shaft 13. Is pushed into.

In the third step of FIG. 3, the first composite pipe 31 is pushed and inserted into the horizontal shaft 13 from the starting vertical shaft 11 side as described above, and the propulsion pipe array with the excavator in the horizontal shaft 13 is moved to the reaching vertical shaft 12 side. When pushed, the propulsion pipe 21 at the head of the propulsion pipe array comes out of the side shaft 13 and plunges into the reaching shaft 12. The leading propulsion pipe 21 that has rushed into the reaching shaft 12 is disconnected from the propulsion pipe array (the second propulsion pipe 21 from the beginning), taken into the reaching shaft 12, and then carried out to the ground side. Be done. During this time, the propulsion jack 63 of the hydraulic mechanism 62 returns to the old position and maintains a state in which the next compound pipe pushing operation is possible.

In the case of the first composite pipe 31 that is inserted by being inserted into the horizontal shaft 13, the rear end outer peripheral surface (connection end outer peripheral surface) of the first drain pipe 41 is exposed in the starting shaft 11 or the first protection is performed. The rear end (connection end) of the pipe 51 is close to one end of the horizontal shaft 13 (the end on the starting shaft 11 side). Therefore, when connecting the front end of the second composite pipe 31 to the rear end of the first composite pipe 31, the rear end of the first drain pipe 41 and the front end of the second drain pipe 41, and the first protection The rear end of the pipe 51 and the rear end of the second protection pipe 51 are connected to each other. The specific connection in such a case is as follows. First, in the case of the first drain pipe 41 and the second drain pipe 41, the front end portion of the second drain pipe 41 is abutted to the rear end portion of the first drain pipe 41 and the outer peripheral surfaces of the abutting portions of both pipes are attached. The split type connecting outer pipe 45 is covered, and the split type connecting outer pipe 45 is connected by being fastened with a fastening band 47. That is, the first drain pipe 41 and the second drain pipe 41 are connected to each other through the connecting means described above with reference to FIGS. 10 and 11. Next, in the case of the rear end portion of the first protection tube 51 and the second protection tube 51, these have the above-mentioned male screw 52 and female screw 53 at their respective ends, so that after the first protection pipe 51, The first protection pipe 51 and the second protection pipe 51 are connected to each other by screwing the end portion into the tip end portion of the second protection pipe 51. With such a connection, the second drain pipe 41 and the second protection pipe 51, which are overlapped inside and outside, constitute the second composite pipe 31. Therefore, it can be said that this is a connection accompanied with the production of the composite pipe 31. Thus, when the respective pipes are connected to each other, the connection of the second composite pipe 31 to the first composite pipe 31 is completed, so that the second composite pipe 31 and the propulsion jack 63 are also connected by the bearing pipe 67 here.

In the third step shown in FIG. 3, when the second composite pipe 31 is pushed into the shaft 13 for insertion, it is performed by the propulsion jack 63 of the hydraulic mechanism 62 as described above. More specifically, the second protection pipe 51 is pushed in by the propulsion jack 63 and the second drain pipe 41 is pushed in at the same time. The second composite pipe 31 advances into the first composite pipe 31 by this pushing, and the second composite pipe 31 itself also enters the horizontal shaft 13. The propulsion pipes 21, that is, the propulsion pipe arrays that are in a line in the horizontal shaft 13, are pushed toward the reaching vertical shaft 12 side by the second protective pipe 51 that also enters the horizontal shaft at this time. Therefore, also at this time, the propulsion pipe 21 at the head of the propulsion pipe array comes out of the side shaft 13 and plunges into the reaching shaft 12. This propulsion pipe 21 that has entered the reaching shaft 12 is also disconnected from the propulsion pipe array and taken into the reaching shaft 12, and then carried out from there to the ground side. During this time, the propulsion jack 63 of the hydraulic mechanism 62 returns to the old position by returning as described above, and maintains the posture in which the next compound pipe pushing operation is possible.

Also in the case of the second composite pipe 31 pushed and inserted into the side shaft 13, the outer peripheral surface of the rear end portion of the second drain pipe 41 is exposed in the starting shaft 11 or the rear end portion of the second protective pipe 51. Is close to one end of the side pit 13. Also when connecting the rear end of the second composite pipe 31 to the next front end of the third composite pipe 31, the rear end of the second drain pipe 41 and the front end of the third drain pipe 41 are in accordance with the procedure described above. The parts may be connected to each other, or the rear end of the second protective pipe 51 and the rear end of the third protective pipe 51 may be connected to each other. Even when such a pipe connection is used, the third drain pipe 41 and the third protective pipe 51, which are overlapped inside and outside, constitute the third composite pipe 31. Furthermore, the point that the third composite pipe 31 and the propulsion jack 63 are connected via the pressure bearing pipe 67 is also the same as above.

When the third composite pipe 31 described above is inserted by being pushed into the shaft 13, it is the same as above. It is to push the third protection pipe 51 with the propulsion jack 63 and at the same time push the third drain pipe 41 with the pushing portion 66 of the propulsion jack 63. Thus, the third composite pipe 31 becomes the first composite pipe 31. While advancing the second composite pipe 31 and itself, it also enters the side shaft 13. Also at this time, the second protection pipe 51 entering the side shaft 13 pushes the propulsion pipe array in the side shaft 13 toward the reaching shaft 12 side, so that the propulsion pipe 21 at the head of the propulsion pipe array is moved to the side shaft 13 It escapes from the inside and plunges into the reaching shaft 12. The propulsion pipe 21 in the pit entry state is also disconnected from the propulsion pipe array and taken into the reaching vertical shaft 12, and then carried out to the ground side. During this time, the propulsion jack 63 of the hydraulic mechanism 62 returns to the old position by returning as described above, and maintains the posture in which the next compound pipe pushing operation is possible.

When the fourth composite pipe 31 and the subsequent composite pipes 31 are pushed and inserted into the horizontal shaft 13, all the main work is performed with the contents substantially the same as or similar to the contents described above. That is, regarding the leading composite pipe 31 and the trailing composite pipe 31 that are in a front-to-back relationship on the side of the starting shaft 11, the front end portion of the subsequent composite pipe 31 is connected to the rear end portion of the preceding composite pipe 31 or is supported between predetermined portions. After the pressure pipe 67 is fixed by interposing, the subsequent composite pipe 31 is pushed and inserted into the horizontal shaft 13 via the propulsion jack 63 of the hydraulic mechanism 62. On the other hand, with respect to the propulsion pipe array remaining in the horizontal shaft 13, each time the composite pipe 31 is pushed into the horizontal shaft 13, the composite pipe 31 is removed from the horizontal shaft 13 and rushes into the reaching vertical shaft 12, so that is described above. It is removed and carried to the ground side. The fourth step, which is schematically shown in FIG. 5, is a series of composite pipe laying from the starting shaft 11 side to the reaching shaft 12 side, that is, the horizontal shaft, due to the insertion and insertion of the composite pipe into the horizontal shaft 13 for a predetermined number of times. This is the stage where a series of composite pipe installations that penetrate through the mine 13 have been completed.

After the composite pipe 31 is laid in the horizontal shaft 13 in the connected state as described above, the protective pipes 51, which are the constituent elements of the connecting composite pipe 31, are provided from the horizontal shaft 13 to the starting shaft 11 side or the reaching shaft 12. Pull it out to the side and remove it. This will be described with reference to the fifth step schematically shown in FIG. 6 and the sixth step schematically shown in FIG. 7.

In the case of the drain pipes (connection drain pipes) 41 laid in the horizontal shaft 13 together with the protection pipe 51 in the above-described connected state, it is clear with reference to the fifth step schematically shown in FIG. As described above, it is held so as not to escape from the side shaft 13 as a temporary detention measure. In other words, each drain pipe 41 is held in a stationary state in the shaft 13 without movement. As means for holding the connection drain pipe (41, 41, 41...) In the underground mine staying state, the holding ropes for retention or mooring having tensile strength are exemplified in FIGS. 6 and 7. 71, disc-shaped or ring-shaped holding plates 72 and 73, anchors 76, and the like. The holding rope 71 is made of a wire rope as a typical example, and the holding plates 72 and 73 and the anchors 76 are made of metal as an example, and synthetic resin as another example. The outer diameters of the disc-shaped or wheel-shaped holding plates 72 and 73 are equal to or slightly smaller than the outer diameter of the drain pipe 41. As shown in FIG. 6B, holes 74 and 75 are formed in the central portions of both the holding plates 72 and 73 for allowing the holding rope 71 to pass therethrough. Each of the holding plates 72 and 73 is further provided with a single hole or a plurality of holes (not shown) for binding and fixing the holding cord 71 to the holding plates 72 and 73, and/or In some cases, a single or a plurality of stoppers (not shown) for fixing the holding cord 71 to the holding plates 72 and 73 are attached to the plate surface.

As is clear with reference to FIG. 6(a), both holding plates 72 and 73 are connected to the rear end surface (starting shaft 11 side) or the front end surface (arriving shaft 12 side) of the connection drain pipe (41, 41, 41...). ) Is concentrically addressed to. That is, both holding plates 72, 73 are concentrically overlapped with both end faces of the connection drain pipe (41, 41, 41... ). Therefore, in this case, the outer peripheral portions of the two holding plates 72 and 73 do not protrude into the end surface region of the protective tube 51. The holding plate 72, which is assigned to the rear end surface of the connection drain pipe (41, 41, 41...), and the holding plate 73, which is assigned to the front end surface of the connection drain pipe (41, 41, 41...), The holding rope 71 is pulled over these. As a specific example thereof, the tip portion of the holding cord 71 that penetrates the hole 75 of the one holding plate 73 from the reaching shaft 12 side passes through the inside of the connection drain pipe (41, 41, 41... ). Thus, the other holding plate 72 is passed through the hole 74. The end portion of the holding cord 71 on the side of the holding plate 72 is fixed to the holding plate 72 by an appropriate means such as lashing or metal fitting. The end portion of the holding cord 71 on the side of the holding plate 73 is in a state in which it can be tightened through a known appropriate tightening device (not shown) such as a jack type, a winch type, and other types. In this case, for example, a detent metal fitting is attached to the holding plate 73 so as to correspond to the hole 75, the end portion of the holding rope 71 on the holding plate 73 side is tightened by a tightening device, and the tightened state is clamped. When this is done, the distance between the two holding plates 72, 73 is reduced, but the connecting drain pipes (41, 41, 41...) Receive pressure in the compression direction from both axial ends. With this, the drain pipes (41, 41, 41,...) Are gathered in the axial direction, and the drain pipes (41, 41, 41...) Are sandwiched and held by the two holding plates 72, 73. The end portion of the holding rope 71 on the side of the holding plate 73 is further connected to an anchor-shaped anchoring tool 76 attached to the rear peripheral surface of the reaching shaft 12 by a well-known appropriate anchoring means (fastening or metal fitting stop). Can be firmly secured with. Since the other end of the holding rope 71 is fixed to the rear peripheral surface of the reaching shaft 12 in this way, the connection drain pipe (41, 41, 41...) Is retained and retained in the horizontal shaft 13. In other words, even if a force (pulling force) acts on the connecting drain pipe (41, 41, 41,...) To pull it out from inside the horizontal shaft 13 to the side of the starting shaft 11 (holding cord). The connection drain pipes (41, 41, 41,...) Held in the horizontal shaft via 71 or the like are retained in the horizontal shaft 13 against the pulling force (pulling force).

In the fifth step of FIG. 6, after each drain pipe 41 in the connected state is held in the above-mentioned stagnation state in the horizontal shaft, a series of each protection pipe 51 (protection pipe array) in the connected state in the horizontal shaft 13 is connected. When completely removing from the side shaft 13, after connecting the rear end of the rearmost protection pipe 51 on the side of the starting shaft 11 and the propulsion jack 63 of the hydraulic mechanism 62 with the pressure bearing pipe 67, the force of the hydraulic mechanism 62 is removed. Then, the protective tube array is pulled out from inside the horizontal shaft 13. A specific example is as follows. In the first work, the propulsion jack 63 moves forward to the one end of the side shaft 13 with a predetermined stroke. In the second work, for example, the rearmost protection pipe 51 and the propulsion jack 63 are connected via the bearing pipe 67 used in the above step. In the third work, the propulsion jack 63 of the hydraulic mechanism 62 returns (returns). The protective tube array is connected to the returning propelling jack 63 as described above. Therefore, the protection tube array is pulled out from the horizontal shaft 13 toward the starting shaft 11 by the backward stroke of the propulsion jack 63. The number of protection tubes 51 that are pulled out from the side shaft 13 to the side of the starting shaft 11 and exposed inside the starting shaft 11 is determined by considering the scale of construction, the diameter of the starting shaft 11, the work process plan, and the like. Is. In the illustrated embodiment, for convenience of description, the protection tube array is extracted from the shaft 13 by the length of one protection tube per one backward stroke of the propulsion jack 63. In this way, when the protection tube array is pulled out from the inside of the horizontal shaft 13, the connection portion between the protection tubes is also exposed inside the starting shaft 11, so that one protection pipe drawn out into the starting shaft 11 is protected. Easy to separate from array. Then, as a fourth work, the connection between the rearmost protection pipe 51 and the pressure bearing pipe 67 is released, or the rearmost protection pipe 51 is separated from the protection pipe array. Of course, since the drain pipe array (the drain pipes 41 in a series of connected states) held in the horizontal shaft 13 in the stationary state as described above is in the horizontal shaft stationary state, it is affected by such withdrawal. Without stopping, stop in the side pit 13 as it is. As the fifth work, the protection tube 51 separated from the protection tube array is carried out to the ground side.

In the fifth step of FIG. 6, the protection tube array is pulled out from inside the shaft 13 by repeating the above-mentioned first to fifth operations, and the protection tube 51 exposed inside the starting shaft 11 is protected. It is separated from the tube array, or the separated protection tube 51 is carried out to the ground.

The sixth step in FIG. 7 shows a stage in which the withdrawal of the protection tube array from the inside of the shaft 13 proceeds, and the last protection tube 51 is withdrawn from the inside of the shaft 13. As for the last protection tube 51, it is pulled out from the shaft 13, the protection tube 51 exposed in the starting shaft 11 is separated from the protection tube array by this extraction, and the separated protection tube 51 is transferred to the ground. Is carried away. It can be said that the drain pipe laying method has completed the predetermined work when the last protective pipe 51 is extracted from the inside of the horizontal shaft 13.

Regarding the removal of the above-mentioned connection protection pipe 51 from the inside of the horizontal shaft 13, for example, the reaching shaft 12 side is equipped with a withdrawal means, or the starting shaft 11 side of the connection drain pipe (41.41.41...). It can be carried out from the reaching vertical shaft 12 side when the means for stopping in the horizontal shaft is equipped.

According to the present invention, a drain pipe laying that is safe, accurate, and easy to construct, a laying construction period can be shortened, a laying construction cost can be reduced, etc. by a construction method mainly composed of a drain pipe and a protective pipe. It is possible. Therefore, it has high industrial applicability as a method of laying a drain pipe.

11 Starting shaft 12 Reaching shaft 13 Lateral resistance 21 Propulsion pipe 22 Connection pipe 31 Composite pipe 32 Cover 33 Tightening band 34 Screw 41 Drain pipe 42 Filter material 43 Net body 44 Annular recess groove 45 Connection outer pipe 46 Annular protrusion 47 Tightening Band 48 Connection inner tube 49 Locking claw 51 Protective tube 52 Male screw 53 Female screw 61 Excavator 62 Hydraulic mechanism 63 Propulsion jack 64 Propulsion base pressing part 65 Reaction force wall 66 Pressing part 67 Supporting pipe 68 Base plate 69 Short pipe 71 Holding rope 72 Holding plate 73 Holding plate 74 Hole 75 Hole 76 Tether

Claims (5)

A drain pipe with water permeability is laid in the underground shaft that penetrates the starting shaft and the reaching shaft from the surface side to the vertical direction in the ground in the horizontal direction to connect the compatible shaft to each other. In the construction method for
When laying a composite pipe in which the drain pipe is installed inside a protection pipe for protecting the drain pipe over the entire length of the shaft, the starting shaft is located at one end of the shaft at the reaching shaft side. Pushing in and inserting the composite pipe toward the other end of the shaft, and
Laying the drain pipe from one end to the other end of the shaft by repeating pushing of the composite pipe into the shaft, and
The drain pipe laying method characterized by. In the drain pipe laying method according to claim 1,
When the propulsion pipe is left in the side shaft, the drain pipe laying method is characterized in that the propulsion pipe is pushed out from the inside of the side shaft to the reaching vertical shaft side through the composite pipe to be pushed in and removed. In the drain pipe laying method according to claim 1 or 2,
A drain pipe laying method, characterized in that a protective member is applied to a rear end surface of the composite pipe when the composite pipe is pushed and inserted into the horizontal shaft, and the pushing insertion force applied to the protective member is transmitted to the composite pipe. In the underground shaft which penetrates horizontally between the starting shaft and the reaching shaft going from the surface side to the vertical direction in the underground and making the compatible shaft in communication with each other, and in the protection pipe for protecting the drain pipe, Regarding the relative relationship with the composite pipe in which the drain pipe is installed, the composite pipe is laid from one end to the other end of the shaft, and
In the construction method on the premise that the protection pipe of the composite pipe is removed from the inside of the shaft and the drain pipe is left in the shaft,
After the drain pipe is held in the horizontal shaft so that the drain pipe stays in the horizontal shaft, the protection pipe is pulled out from the horizontal shaft to the starting vertical shaft side or the reaching vertical shaft side. .. A drain pipe with water permeability is laid in the underground shaft that penetrates horizontally between the starting shaft and the reaching shaft running from the surface side to the vertical direction of the ground, making the compatible shaft in communication. In the construction method for
When laying a composite pipe in which the drain pipe is housed in a protection pipe for protecting the drain pipe over the entire length of the shaft, the starting shaft is located at one end of the shaft at the reaching shaft side. Pushing in and inserting the composite pipe toward the other end of the shaft, and
Laying the drain pipe from one end to the other end of the shaft by repeating pushing of the composite pipe into the shaft, and
Drain pipe laying, characterized in that after holding the drain pipe in the horizontal shaft stop state so that the drain pipe remains in the horizontal shaft, the protection pipe is pulled out from the horizontal shaft to the starting vertical shaft side or the reaching vertical shaft side. Construction method.

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