JP2889186B2 - Drainage pipe structure using plastic composite pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a plastic composite pipe, which is used for sewage, rainwater and other drainage, and other fluids.
For example, the present invention relates to a drain pipe structure configured to be able to transport sludge and water separately.

[0002]

2. Description of the Related Art Generally, a sewage treatment plant is provided with a sludge treatment facility, but some sewage treatment plants do not have a sludge treatment facility. In this case, the sludge settled and separated by the sewage treatment plant without the sludge treatment facility is transported to a sewage treatment plant with a sludge treatment facility using a sludge pipe and treated. Usually, a sewage treatment plant having a sludge treatment facility and a sewage treatment plant having no sludge treatment facility are relatively far away from each other. Therefore, laying a sludge pipe requires a lot of labor and cost.

[0003]

SUMMARY OF THE INVENTION Accordingly, the present inventors
It was concluded that the simultaneous installation of sludge pipes in existing or newly installed sewer pipes would reduce the labor required for laying sludge pipes. Also, considering the ease of handling at the time of laying the sludge pipe and the durability in a corrosive environment, it has been concluded that it is preferable to use a lightweight and corrosion-resistant plastic pipe for the sludge pipe. .

[0004] However, there are various types of sludge, and the fluidity of the sludge varies from as good as sewage to very poor, and when sludge with poor fluidity is transported. Requires high pressure to be pumped. In such a case, simply arranging the sludge pipe in the drainage pipe causes the sludge pipe to expand or shrink due to sludge pulsation or pressure fluctuations, so that the sludge pipe moves or bends.
Anxiety remains from the viewpoint of the reliability of the strength of the sludge pipe and the joint of the sludge pipe. In addition, since various substances such as acids, alkalis, and organic substances are contained in the sewage, it is not always preferable to use the pipes directly exposed to the sewage even when using a plastic pipe having high corrosion resistance. . In addition, if the plastic pipe is supported on the inner wall of the sewer pipe by a bracket or the like, foreign matters contained in the sewage catch on the bracket, and the flow of the sewage is obstructed. For these reasons, it has been concluded that it is preferable to embed and use a plastic tube with concrete.

However, when a plastic pipe through which high-pressure sludge passes is embedded in concrete, the rigidity of the plastic pipe is significantly lower than that of a metal pipe or the like. Therefore, when the pressure of the fluid in the plastic pipe increases, the plastic pipe expands in the radial direction. To try. In this case, since the inner peripheral surface of the plastic tube is not completely round, the inner peripheral surface of the plastic tube tends to have the most stable shape of a perfect circle. For this reason, the concrete around the plastic pipe receives a particularly large tensile load in a specific direction, and the concrete tends to break relatively easily. This tendency is remarkable when the pressure in the pipe fluctuates suddenly, and particularly when sludge or the like having poor fluidity is pumped, the pressure fluctuates easily.

In order to prevent such a phenomenon, it is conceivable to adopt a composite pipe structure in which the periphery of the plastic pipe is reinforced with a metal plate or the like so that the pressure in the plastic pipe is not transmitted to the surrounding concrete. However, in this case, in most cases, there is also a problem that the flexibility of the entire plastic tube is significantly impaired, and the laying work becomes difficult.

The present invention has been made in view of the above, and is made of a plastic composite pipe suitable for sludge pumping, that is, hardly deformed by internal pressure, and does not transmit a load to the outside even when deformed. Another object of the present invention is to provide a plastic composite pipe having sufficient flexibility and easy handling, and to provide a drain pipe structure capable of transporting sludge and sewage separately using the plastic composite pipe. I do.

[0008]

In order to achieve the above object, the present invention provides a drain pipe, a concrete body fixed to an inner wall of the drain pipe and extending in an axial direction of the drain pipe, and a concrete body. A plastic composite pipe embedded in the inside of the drain pipe and extending along the axial direction of the drainage pipe, wherein the plastic composite pipe has a predetermined gap formed between a conduit made of a resin material and side edges adjacent to each other. The first steel strip spirally wound on the conduit so as to cover the gap between the side edges of the first steel strip and form a predetermined gap between adjacent side edges. A second steel strip spirally wound on the first steel strip in the same winding direction as the first steel strip; and a radius of the conduit provided on the second steel strip and made of a foamed resin material. For deformation of direction Ri is deformed when subjected to a load,
And a buffer material layer for suppressing a change in outer diameter of the plastic composite pipe.

[0009]

[0010]

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 are views showing an embodiment of the present invention.

First, referring to FIG. 3, a drain pipe 8 is used as a drain pipe.
The drain pipe structure 70 using 0 will be described. As shown in FIG. 3, the drain pipe structure 70 includes a sewage pipe 80 for flowing down normal sewage, a concrete body 90 fixed to an inner peripheral wall 81 of the sewage pipe 80, and a sewage pipe 2 embedded in the concrete body. And two plastic composite tubes 1.

The concrete body 90 is provided diagonally below the sewage pipe 80 and has a stepped shape including a first step portion 91 and a second step portion 92. The concrete body 90 extends in the axial direction of the sewer pipe 80.

Each of the plastic composite tubes 1 has a first
The step section 91 and the second step section 92 are arranged at substantially the center of the cross section, and extend in the axial direction of the sewer pipe 80. Each of these plastic composite pipes 1 is embedded in a concrete body 90 after being positioned by a plurality of brackets 82 provided at predetermined intervals in the axial direction of an inner peripheral wall 81 of a sewer pipe 80. The drainage pipe structure 70 thus configured is
While the sewage flows down by the main body of the sewage pipe 80, sludge can be pumped by the plastic composite pipe 1.

Next, the plastic composite pipe 1 constituting the drain pipe structure 70 will be described. As shown in FIG. 1, a plastic composite pipe 1 includes a conduit 10 made of a resin material and a cloth layer 20 provided on the outer peripheral surface of the conduit 10.
And a reinforcing layer made of a steel strip (first steel strip 30 and second steel strip 40) wound on the cloth body layer 20, and a cushioning material made of a foamed resin material provided on the reinforcing layer Layer 50;
Corrosion protection layer 6 made of a resin material provided on buffer material layer 50
0.

The conduit 10 has a substantially cylindrical shape,
It is made of high-density polyethylene (high-density polyethylene specified in JIS K6760) and has a substantially cylindrical shape. The conduit 10 is made of a resin material having appropriate strength, durability, and flexibility (flexibility) other than high-density polyethylene, such as medium-density polyethylene (MDPE), low-density polyethylene (LDPE), and linear low density. It may be formed of a resin material such as polyethylene (LLDPE), cross-linked polyethylene (XL-PE), or polypropylene (PP).

As shown in FIG. 2 (a), the cloth layer 20 is made of a sheet 21 made of polyethylene non-woven fabric.
It is formed by winding so as to wrap around 0.
As shown in FIG. 1B, both ends 21a and 21b of the sheet 21 are wound so as not to overlap with each other. The cloth body layer 20 is made of a polyethylene nonwoven fabric,
It may be formed of a polyester nonwoven fabric, a polyester tape, or a nonwoven fabric or tape made of a resin material.

Next, the first steel strip 30 and the second steel strip 40 constituting the reinforcing layer will be described. The first steel strip 30 and the second steel strip 40 are made of a thin strip made of stainless steel such as SUS304. The first steel strip and the second steel strip are not limited to stainless steel, and may be formed of a steel band other than stainless steel.

As shown in FIG. 2 (b), the first steel strip 30 has no overlapping portions, that is, a predetermined gap is formed between the adjacent side edges 31a and 31b. It is spirally wound on the cloth tape layer 20. As shown in FIGS. 1A and 2B, when the width of the first steel strip 30 is w, the gap between the adjacent side edges 31a and 31b of the first steel strip 30 is 1 / 3
w.

As shown in FIGS. 1A and 2C, the second steel strip 40 has a width w substantially equal to that of the first steel strip 30.
And have a thickness. The second steel strip 40 is formed so as to cover the gap between the side edges 31a and 31b of the first steel strip 30.
The first steel strip 3 is spirally wound around the steel strip 30.
The spiral directions of the 0 and the second steel strip 40 are the same. Similarly to the first steel strip 30, the second steel strip 40 has a predetermined gap 1 / 3w between the side edges 41a and 41b adjacent to each other.
Is formed so as to be formed. FIG.
As shown in (a), the second steel strip 40 and the first steel strip 30 overlap each other on both side edges 31a, 31b, 41a, 41b, but the overlap margin, that is, the second steel strip 40, and the second steel strip 30
The length of the portion where the steel strip 40 and the first steel strip 30 overlap each other is 1 / 3w. That is, the second steel strip 40
Is located on the center of the gap between the first steel strips 30.

As shown in FIG. 2D, the cushioning material layer 50 is formed by winding a sheet 51 made of expanded polypropylene so as to wrap around the second steel strip 40. Further, as shown in FIG. 1B, both ends of the sheet 51 are wound so as not to overlap with each other. In addition, the cushioning material layer 50 is, besides foamed polypropylene,
For example, a foamed resin material such as foamed polyethylene, foamed crosslinked polyethylene, foamed polystyrene, foamed polyurethane, or the like may be used as long as it is made of a material that functions as a cushion.

The anticorrosion layer 60 is formed by covering low-density polyethylene on the buffer layer 50 by extrusion. The anticorrosion layer 60 can be appropriately selected from resin materials having strength, durability, and flexibility (flexibility) in addition to low-density polyethylene. For example, high-density polyethylene, medium-density polyethylene, linear It may be selected from materials such as low density polyethylene, cross-linked polyethylene, and polypropylene.

The conduit 10, the cloth tape layer 20, the reinforcing layer composed of the first and second steel strips 30, 40, the cushioning material layer 50, and the anticorrosion layer 60, which constitute the plastic composite pipe 1, are described above. They are stacked without being fixed to each other by adhesion or the like.

Next, the operation of the present embodiment having the above configuration will be described.

First, the operation at the time of manufacturing and laying the plastic composite pipe 1 will be described. As described above, the cloth tape layer 20, the reinforcing layer composed of the first and second steel strips 30, 40, and the cushioning material layer 50 are sequentially wound on the outer peripheral surface of the conduit 10, and then the anticorrosion layer 60 is extruded.
Is formed on the cushioning material layer 50, and the plastic composite tube 1 is manufactured. The manufactured plastic composite tube 1 is wound and stored on a winding roll (not shown) for storage and transportation. Then, the plastic composite pipe 1 is conveyed to the site and laid, and then used as appropriate.

In this case, as described above, the reinforcing layer is formed by the first layer.
The steel strip 30 and the second steel strip 40 are constituted by two steel strips, and the first steel strip 30 and the second steel strip 40 form a predetermined space between the adjacent side edges 31a, 31b, 41a, 41b. The first steel strip 30 and the second steel strip 40 are not fixed to each other and can slide on each other. Therefore, the plastic composite pipe 1 can be easily bent, and can be easily restored to the original state even after the bending. On the contrary,
For example, when the first steel strip 30 and the second steel strip 40 are fixed to each other, the first steel strip 30 and the second steel strip 40 become a substantially unitary cylindrical body, and therefore a plastic composite is used. It becomes extremely difficult to bend the tube 1 and it is also difficult to restore it to its original state after bending.

The reinforcing layer is composed of two steel strips, a first steel strip 30 and a second steel strip 40, and the first steel strip 30 and the second steel strip 40 have side edges 31a, 31 adjacent to each other.
The plastic composite pipe 1 is bent when the conduit 10 expands or contracts due to thermal expansion or the like, or during transportation or pipe construction because it is spirally wound so as to form a predetermined interval between the pipes 41, 41a and 41b. Even in this case, the conduit 10 is not damaged by the edges 31a and 31b of the first steel strip 30. On the other hand, for example, as shown in FIG. 4 (a), the reinforcing layer comprises only the first steel strip 30, and the first steel strip 3
When the peripheral portions of the adjacent side edges 31a and 31b are wound so as to overlap with each other, the first steel strip 30 is bent when the conduit 10 expands or contracts due to thermal expansion or the like or when the plastic composite pipe 1 is bent. Side edges 31a and 31b of the conduit 10
However, according to the present embodiment, such a problem does not occur.

Further, since the cloth layer 20 is provided below the first steel strip 30, the conduit 10 and the first steel strip 30 do not come into direct contact with each other. Therefore, the plastic composite pipe 1
Is bent, the side edges 31a and 31b of the first steel strip 30 can more completely prevent the conduit 10 from being damaged.

Since the overlap between the first steel strip 30 and the second steel strip 40 is 1/3 w, the plastic composite determined by the overlap between the first steel strip 30 and the second steel strip 40 is set. The pressure resistance of the entire pipe 1, that is, the pressure resistance to the pressure in the conduit 10, can be sufficiently ensured. Further, even if the plastic composite pipe 1 is laid in a largely bent state, as shown in FIG. 4B, the overlap between the first steel strip 30 and the second steel strip 40 is sufficiently (w ₁ , w ₂ ). Therefore, the pressure resistance of the bent portion of the laid plastic composite pipe 1 does not significantly decrease.

As described above, the first steel strip 30 and the second steel strip 40 have the same width w, and the first steel strip 30 and the second steel strip 40 are adjacent to the side edges 31a, 31b, 41.
a and 41b are spirally wound so as to form a predetermined interval of 1 / 3w, the spiral directions of the first steel strip 30 and the second steel strip 40 are the same, and the first steel strip 30 and the second steel strip 30 are spirally wound. By setting the overlapping allowance of the steel strip 40 to 1/3 w, the flexibility and the pressure resistance of the plastic composite pipe 1 can be optimally compatible. In addition, since the width of the first steel strip 30 and the width of the second steel strip 40 are both the same w, the equipment for manufacturing the plastic composite pipe 1 can be simplified.

In addition to the first steel strip 30 and the second steel strip 40, the conduit 10, the cloth tape layer 20, the reinforcing layer (the first steel strip 30, the second steel strip 40), the cushioning material layer 50, Also, since the anticorrosion layer 60 is not fixed to each other, an appropriate slip occurs between the respective layers when the plastic composite pipe 1 is bent.
Therefore, it is easier to bend the plastic composite pipe 1.

As described above, the plastic composite pipe 1
Has sufficient flexibility as a whole. For this reason, the plastic composite pipe 1 can be easily wound around the winding roll, and the space required for storing the plastic composite pipe 1 can be reduced, and the plastic composite pipe 1 can be easily transported to the laying site. In addition, the plastic composite pipe 1 can be easily bent into an appropriate shape and can be easily returned to the original shape after being bent once, so that the plastic composite pipe 1 can be easily laid.

If it is known in advance that the plastic composite pipe 1 is to be laid in a straight line, the first steel strip 30
The overlap margin between the second steel strip 40 and the second steel strip 40 may be set to a value smaller than 1 / 3w, for example, about 1 / 4w. However, in this case, since the overall pressure resistance of the plastic composite pipe 1 is reduced, the usage conditions of the plastic composite pipe 1, for example, the pressure of the fluid passing through the conduit 10, must be noted.
It is necessary to pay attention to the method of laying, for example, the strength of the member covering the periphery of the plastic composite pipe 1.

Next, the operation of the plastic composite pipe 1 and the drainage pipe structure 70 using the plastic composite pipe 1 when pumping sludge will be described. First, sludge settled and separated at a sewage treatment plant without a sludge treatment facility,
The plastic composite pipe 1 provided in the drainage pipe structure 70 is pumped to a sewage treatment plant having a sludge treatment facility.
When the sludge is being pumped, the pressure in the conduit 10 of the plastic composite pipe 1 fluctuates and a high pressure may be applied inside the conduit 10. Since the first steel strip 30 and the second steel strip 40 are provided, radial deformation of the conduit 10 is suppressed to a minimum.
Even if the first steel strip 30 and the second steel strip 40 are provided, when a high pressure is applied inside the conduit 10, the first steel strip 30 and the second steel strip 40 are elastically deformed, and the conduit 10, The cloth body layer 20, the first steel strip 30, and the second steel strip 40 may be slightly radially deformed as a whole. In this case, the deformation is absorbed by the cushioning material layer 50 acting as a cushion, so that no load is applied to the concrete body 90 in which the plastic composite pipe 1 is embedded.
For this reason, the thickness of the concrete body 90 can be set to be thin, and the decrease in the cross-sectional area of the flow passage in the sewer pipe 80 can be minimized. Therefore, it is possible to obtain the drain pipe structure 70 in which the sludge pumping path is provided in the drain pipe 80 without impairing the function of the drain pipe 80 itself. That is, according to the present embodiment, it is possible to provide a sludge pumping route using the drain pipe that has been conventionally laid as it is,
Even when a new drain pipe is laid, a sludge pumping path can be provided without increasing the inner diameter of the drain pipe. For this reason, the laying cost of the sludge pipe can be reduced.

It is also conceivable that sewage may pass through the joints of the concrete body 90 or the concrete body 90 itself and reach the plastic composite pipe 1 due to aging of the concrete body 90 or the like. Is provided with an anticorrosion layer 60 made of a resin material, so that infiltration of sewage into the plastic composite pipe 1 can be prevented.

In the embodiment described above, an example is shown in which the drainage pipe is the sewage pipe 80 and the sludge is pumped by the plastic composite pipe 1, but the present invention is not limited to this. That is, the drain pipe may be a pipe for transporting rainwater or the like, or the one transported or pumped by the plastic composite pipe may be a fluid other than sludge, for example, water.

[0042]

[Example] Inside diameter: 198 mm, outside diameter: 232 mm, wall thickness: 17
A high-density polyethylene pipe having a size of 10 mm was prepared as a conduit 10 and a weight of 40 g / m
^2. A polyester nonwoven fabric having a thickness of 0.17 mm was wound to form a cloth layer 20. Next, a strip-shaped first steel strip 3 made of SUS304 having a width of 150 mm and a thickness of 0.1 mm.
No. 0 and the second steel strip 40 were prepared and wound sequentially on the cloth body layer 20. Next, a foamed polypropylene sheet having a thickness of 8 mm was wound around the second steel strip 40 to form the cushioning material layer 50. Next, a low-density polyethylene having a thickness of 4.0 mm was coated by extrusion molding to form an anticorrosion layer 60, and a plastic composite pipe 1 was obtained. The cushioning material layer 50 was compressed when covering the anticorrosion layer 60, and the thickness of the plastic composite tube 1 when completed was approximately 7 mm. In this case, the cloth layer 2
0, first steel strip 30, second steel strip 40, and cushioning material layer 50
Was carried out according to the method described in the embodiment of the present invention described above.

The plastic composite pipe 1 obtained as described above was subjected to (A) an invert crack test,
(B) An outer diameter change amount confirmation test and (C) a pull-in test were performed. Hereinafter, test methods and test results will be described sequentially.

(A) Invert Crack Test (1) Test Method The plastic composite tube 1 having the above-mentioned specification was cut into a length of 5 m, and both ends were sealed with lids 101 and 102. This plastic composite tube 1 was embedded in the center of an invert 100 (straight) as shown in FIGS. 5 (a) and 5 (b). The invert 100 has a substantially square cross section as shown in FIG. 5B, and the thickness of the concrete is 75 mm in the vertical and horizontal center axis directions. The thickness of the concrete is substantially equal to the thickness of the concrete surrounding the plastic composite pipe 1 when the plastic composite pipe 1 is laid in the drainage pipe. In this test, blast furnace cement BB (strength 225 kgf / cm ^2, slump 15 cm, maximum aggregate 20 mm) was used as the concrete constituting the invert 100. Then, Invert 1
The strain gauges 105a to 105e (KC-70-120 manufactured by Kyowa Dengyo) are placed on the outer surface of the 00 at the positions shown in FIGS.
-A1-11). Further, a high-pressure water source 103 and a pressure gauge 104 were connected to the lid 101 side.

Next, change from the high pressure water source 103 to introduce high-pressure water in the conduit 10 of the plastic composite tube 1, the pressure in the conduit 10 alternately at 2 minute intervals between 0kgf / cm ² ~15kgf / cm ² I let it. At this time, the presence or absence of breakage of the concrete constituting the invert 100 was constantly monitored, and the amount of strain measured by the strain gauges 105a to 105e was monitored. The internal pressure of 15 kgf / cm ² is about three times the pressure applied when sludge is transported by the plastic composite pipe 1.

As a comparative sample, a plastic composite tube without the buffer material layer 50 was prepared, and a test was performed in the same manner as described above.

[0047] (2) was repeated 400 times the pressure fluctuation between the test results 0kgf / cm ² ~15kgf / cm ² breaking the concrete did not occur. In addition, the amount of strain measured by the strain gauges 105a to 105e was also within the range of drift caused by a change in the outside air temperature, and no strain was detected. On the other hand, when a plastic composite tube without the buffer layer 50 was used, cracks occurred on the upper surface of the invert 100 when the pressure in the conduit 10 became 9.5 kgf / cm ² .

(B) Confirmation Test of Outer Diameter Change (1) Test Method As shown in FIG. 6, the plastic composite pipe 1 having the above-mentioned specification is cut into a length of 1.4 m, and both ends are covered with lids 111 and 112.
And sealed. The high-pressure water source 113 and the pressure gauge 1
14 was connected to the lid 111 side. Next, high-pressure water is introduced into the conduit 10 of the plastic composite tube 1 from the high-pressure water source 113, and the pressure in the conduit 10 is gradually increased to 0 kgf / cm ² ,
FIG. 6 shows the change in the outer diameter of the plastic composite tube 1 at each of 7 kgf / cm ² , 10 kgf / cm ² , and 15 kgf / cm ² .
Were measured at points a to e shown in FIG. (2) Test results The test results are shown in Tables 1 and 2. Table 1 shows the results of the first test, and Table 2 shows the results of performing the same test again on the same sample that has undergone the first test.

[0049]

[Table 1]

[0050]

[Table 2] As shown in Tables 1 and 2, the change in the outer diameter of the plastic composite tube 1 was extremely small. As a comparative sample, a plastic composite tube without the buffer material layer 50 was prepared, and a test was performed in the same manner as described above. Table 3 shows the test results.

[0051]

[Table 3] Comparing the test results shown in Tables 1 and 2 with the test results shown in Table 3, the deformation amount of the outer diameter when the pressure in the conduit 10 is the same is larger without the buffer layer 50. ,
The cushion effect of the cushioning material layer 50 can be confirmed.

(C) Pull-in test (1) Test method This test is based on the assumption that the plastic composite pipe 1 is pulled into a shaft. That is, the plastic composite pipe 1 is set in a virtual shaft 120 indicated by a chain line in FIG.
Guide rollers 121a to 121a
1i was arranged as shown in FIG. Also, the pull-in device 12
2 is disposed downstream of the guide rollers 121a to 121i. Next, the plastic composite pipe 1 is passed along the guide rollers 121a to 121i to the drawing device 122, and the drawing force (tensile force) at the position of the drawing device 122 is 750 kg.
The plastic composite pipe 1 was pulled in by the pull-in device 122 so as to obtain f. In this case, the guide rollers 121a to 121a
The radius of curvature of the plastic composite pipe 1 bent according to 21d is 5 m, and the radius of curvature of the plastic composite pipe 1 bent according to the guide rollers 121e to 121i is 5.5m.
The guide rollers 121a to 121i are arranged such that Then, when the plastic composite pipe 1 is drawn in by the drawing-in device 122, the deformation of the anticorrosion layer 60 and the conduit 1
The presence or absence of the deformation of 0 was confirmed at positions A and B. (2) Test Results The plastic composite pipe 1 has guide rollers 121e to 121e.
Position A and position B when retracted following 1i
Thus, as shown in FIG.
Deformation of a convex shape having a pitch of approximately 14 mm in height occurred. However, when the plastic composite tube 1 reached the position of the retracting device 122, approximately 90% of the portions where the convex deformation occurred had recovered to the initial state. Even in the remaining 10%, after the concrete was cast, the deformation of the convex shape was recovered to such an extent that the concrete was not adversely affected. Also, no deformation of the conduit 10 was observed.

The radius of curvature of the plastic composite pipe 1 bent along the guide rollers 121a to 121d is as follows:
When the guide rollers 121a to 121i were arranged such that the radius of curvature of the plastic composite pipe 1 bent along the guide rollers 121e to 121i was 7 m, no deformation of the anticorrosion layer 60 and the conduit 10 occurred.

[0054]

As described above, by using a plastic composite tube which has sufficient deformation resistance to the pressure in the conduit and does not transmit the pressure in the conduit to the outside,
Even when the thickness of the concrete body is set to be thin, a drain pipe structure having sufficient durability can be obtained. Therefore, since it is possible to minimize the decrease in the cross-sectional area of the drain pipe, without impairing the drainage transport function of the drain pipe itself,
Transport routes for sludge, water, etc. can be provided in existing drainage pipes.Also, even when a transport route for sludge, water, etc. is provided in a new drainage pipe, it is not necessary to make design changes such as increasing the inner diameter of the drainage pipe. Absent. For this reason, it is possible to obtain a drain pipe structure capable of transporting waste water and sludge, water, and the like simultaneously and separately by different routes at a low cost. Further, since the plastic composite pipe has excellent flexibility, it can be easily laid when a drain pipe structure is produced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a plastic composite pipe.

FIG. 2 is a view showing a method of forming a cloth layer, a reinforcing layer, and a cushioning material layer of a plastic composite pipe.

FIG. 3 is a perspective view showing a drainage pipe structure using a plastic composite pipe.

FIG. 4 is a view showing the operation of the steel strip when the method of winding the steel strip is different.

FIG. 5 is a diagram showing a layout of an invert crack test device.

FIG. 6 is a diagram showing a layout of an external change amount confirmation test apparatus.

FIG. 7 is a diagram showing a layout of a pull-in test apparatus.

FIG. 8 is a view showing a change state of a protective layer in a pull-in test.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plastic composite pipe 10 Conduit 20 Cloth layer 30 Reinforcement layer (1st steel strip) 31a, 31b Side edge 41a, 41b (2nd steel strip) Side edge 40 Reinforcement layer (1st steel strip) Obi) 50 Buffer material layer 60 Anticorrosion layer 70 Drainage pipe structure 80 Drainage pipe (sewage pipe) 90 Concrete body

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Aso 843--18 Kasugaura, Oji-shi, Oita City, Oita Prefecture Mitsui Kinzoku Engineering Co., Ltd. Oita Works (56) References Real Opening 59-45386 U) Jiko 2-35908 (JP, Y2) Jiko 5-11427 (JP, Y2) Jiko 59-7669 (JP, Y2) (58) Fields surveyed (Int. Cl. ⁶ , DB name) ) F16L 9/00-11/18

Claims (4)

(57) [Claims] 1. A drain pipe, a concrete body fixed to an inner wall of the drain pipe and extending in the axial direction of the drain pipe, embedded in the concrete body, and extending along the axial direction of the drain pipe. And a plastic composite tube extending, wherein the plastic composite tube is a conduit made of a resin material,
A first steel strip spirally wound on the conduit so that a predetermined gap is formed between the adjacent side edges, and a side adjacent to and covering the gap between the side edges of the first steel strip. A second steel strip spirally wound in the same winding direction as the first steel strip on the first steel strip so that a predetermined gap is formed between the edges, and provided on the second steel strip. And a cushioning material layer which is made of a foamed resin material, deforms when receiving a load due to the radial deformation of the conduit, and suppresses a change in the outer diameter of the plastic composite pipe. Drain pipe structure. 2. The drain pipe structure according to claim 1, wherein a cloth layer is provided between the conduit and the reinforcing layer of the plastic composite pipe. 3. The first steel strip and the second steel strip have the same width, and a gap between mutually adjacent side edges of each of the first steel strip and the second steel strip is the same as that of the first steel strip. Approximately 1/3 of the width of the first and second steel strips
Wherein the overlap of the first steel strip and the second steel strip is approximately 1/3 of the width of the first and second steel strips,
The drainage pipe structure according to claim 1. 4. The drainage pipe according to claim 1, wherein the drainage pipe is used as a sewage transport passage, and the plastic composite pipe is used as a sludge pumping passage. Structure.