JP2999393B2 - Rehabilitation of underground pipes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for rehabilitating a buried pipe underground. The present invention relates to a method of restoring a pipe function when an existing buried pipe such as a sewer pipe is damaged due to an earthquake, a load of a vehicle, or the like. For this purpose, a new pipe is laid inside the buried pipe.

[0002]

2. Description of the Related Art When a pipe such as a sewer pipe buried in the ground is damaged such as a crack, as a method of rehabilitating the pipe, a non-woven fabric layer on an outer surface is impregnated with a thermosetting resin in advance, and a synthetic resin is used. A long tube lined with a film is inserted into the sewer pipe from one manhole to the other manhole, and then the hot water is supplied to the tube to expand it, so that the non-woven fabric layer on the outer surface of the tube is lowered. There has been known a method of internally applying a resin which is brought into close contact with the inner surface of a water pipe and hardens the above-mentioned thermosetting resin.

[0003]

However, the above-mentioned method of sticking a tube inside a damaged tube requires a large boiler, a water supply pump, and the like to inflate and heat the tube inserted into the damaged tube. There is a problem that the cost of these facilities is increased and the strength is remarkably low as compared with the fume pipe constituting the existing sewer pipe.

[0004] The present invention is to lay another pipe in the above-mentioned broken pipe, and can be carried out when the above-mentioned broken pipe is large enough to accommodate a worker. A boiler or feed pump is not required, and it is possible to easily form a pipe with excellent durability in the above-mentioned broken pipe and with excellent strength that does not decrease the flow-down capability despite its narrow cross-sectional area. It is.

[0005]

According to the present invention, there is provided a method for rehabilitating an underground buried pipe, wherein a plurality of segments forming a part of a circular pipe thinner than the buried pipe in the underground buried pipe are formed in a circumferential direction and length. In the method of rehabilitating a buried pipe in which the pipes are connected in the same direction and another circular pipe is laid in the buried pipe, as the above-mentioned segment, a rectangular plate is formed on the outer periphery of the skin plate curved in an arcuate cross-section in a radial direction. A plurality of bolt holes are provided on one of the opposed flanges, and a nut is provided on the other of the opposed flanges, and a working window is provided at an edge of the skin plate on the side where the bolt holes are provided. A hole with an opening is used, a rubber packing is interposed between two adjacent segments, and a bolt is inserted from the inside of the segment through a working window hole to a bolt hole of a flange adjacent to the window hole and an adjacent segment. By inserting the cement flange nut screwing the bolt into the nut, characterized in that block the later working window opening accordingly a synthetic resin.

[0006] The segments are preferably made of a metal plate such as a stainless steel plate. Further, it can be made of FRP in which a synthetic resin such as an epoxy resin or an unsaturated polyester resin is reinforced with a fiber such as a glass fiber or a carbon fiber. And it is preferable that this segment is produced in a shape obtained by dividing a circular pipe into any number of four or more in the circumferential direction,
If the division is three or less, the weight per segment becomes large and it becomes difficult to handle, and when the outer diameter of the circular pipe approaches the inner diameter of the existing buried pipe, it becomes difficult to carry in the segment.

[0007] The above-mentioned segments are formed by projecting radially outward flanges on four sides of a skin plate having a rectangular plate curved into an arc cross section. That is, an arcuate flange is provided along a pair of arc-shaped edges opposed to each other in the axial direction of the skin plate, and a set of straight flanges is provided along a pair of linear edges opposed in the circumferential direction. It is protruding. A rib parallel to the arcuate flange or the straight flange may be provided on the outer surface of the skin plate at substantially the same height as the flange. Also, a plurality of bolt holes are drilled in one of the set of arcuate flanges, and a nut is fixed at a position facing the other bolt hole. Further, a plurality of bolt holes are drilled in one of the set of straight flanges, and a nut is fixed at a position facing the other bolt hole.

[0008] The working window hole provided at the edge of the skin plate is such that a worker inside the skin plate passes a bolt through a bolt hole of the outer arcuate flange and the straight flange, and the head of the bolt is a tool such as a spanner. It is provided in such a size that it can be tightened. It is preferable to provide a box-shaped cover outside the window hole that can cover the window hole in cooperation with the bow-shaped flange or the straight flange. When the box-shaped cover is provided, fastening of the bolt Later, by filling the inside of the box-shaped cover with a synthetic resin, the window hole can be easily closed.

A large number of the above segments are carried into an existing buried pipe, and the other segments are arranged in the circumferential direction and the length direction of one segment, respectively. A rubber packing having substantially the same shape as these flanges is interposed therebetween, and a bolt is screwed into one nut from another bolt hole of the flanges in contact with each other. Here, by using a water-expandable rubber packing as the rubber packing, the sealing property can be improved.

The synthetic resin to be filled in the working window is preferably an epoxy resin or the like. Further, the portion where the filled resin is exposed inside the window hole is preferably formed as a smooth surface having no unevenness with the inner surface of the skin plate. In addition, when laying a new pipe by connecting the above segments in the existing buried pipe, while assembling the new pipe,
By inserting an arbitrary packing between the existing buried pipe and injecting and solidifying a synthetic resin, the new pipe is fixed at a desired position. Further, a bolt may be screwed into a desired portion of the skin plate of the segment from the inside in the radial direction, and the tip may be fixed by being brought into contact with the inner surface of the outer buried pipe.

[0011]

When a part of an existing buried pipe is damaged, the above-mentioned segments are newly connected in the buried pipe by connecting the segments over the entire length between manholes located at both ends of the buried pipe including the damaged part. A circular pipe is laid and the buried pipe is rehabilitated. In this case, the inner diameter of the new pipe is smaller than the inner diameter of the existing pipe, but a work window hole is opened at the edge of the skin plate close to the bolt hole of the flange, and the bolt is skinned through this window hole. The inner diameter of the new pipe, that is, the inner diameter of the circular pipe formed by connecting the skin plate, is larger than the inner diameter of the existing pipe because the inner diameter of the new pipe, that is, the inner diameter of the circular pipe formed by connecting the skin plate, is set. It is only necessary to make it small. Moreover, while the existing pipe is composed of a fume pipe, the new pipe is made of metal or FRP, and the inner surface is smoother than the fume pipe,
In addition, since the above-mentioned window for work is closed, the flowability of the new pipe does not decrease as compared with the existing pipe, and the pipe can be used as in the conventional case.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A segment 10 shown in FIG. 1 has a skin plate 11 formed by dividing a cylinder into four in the circumferential direction, and an arc-shaped flange protruding radially outward along an arcuate edge of the skin plate 11. 12, 13 and the above-mentioned skin plate 1
It is composed of straight flanges 14 and 15 protruding radially outward along one straight edge, and is entirely made of stainless steel plate.

Of the pair of bow-shaped flanges 12, 13, one bolt-shaped flange 12 is provided with three bolt holes 12a, and the other bow-shaped flange 13 is fixed with a nut 13a at a portion facing the bolt-hole 12a. You. Two bolt holes 14a are formed in one of the straight flanges 14 and 15, and a nut 15 is formed in a portion of the other straight flange 15 which faces the bolt hole 14a.
a is fixed.

At the edge of the skin plate 11, one of the pair of bow-shaped flanges 12, 13, ie, the bow-shaped flange 1 having a bolt hole 12a, is provided.
2 is a work window hole 1 in a portion adjacent to the bolt hole 12a.
1a, and one of the straight flanges 14, 15 is provided with a working window hole 11b in a portion of the straight flange 14, that is, a portion of the straight flange 12 having the bolt hole 14a which is close to the bolt hole 14a. And
A box-shaped cover 21 indicated by a dashed line is provided in the work window 11a in contact with the bow-shaped flange 12, and a box-shaped cover 22 indicated by a chain line in the work window 11b in contact with the straight flange 14.

The above-mentioned segments 10 are carried into a buried pipe (not shown) underground from manholes (not shown) opening on the ground, and these many segments 10 are axially and circumferentially transferred. They are arranged side by side. Then, a water-expandable bow-shaped rubber packing 16 having the same shape is sandwiched between one bow-shaped flange 12 and the other bow-shaped flange 13 of two segments 10 adjacent in the axial direction. The bolt 18 is screwed into the nut 13a through the bolt hole 12a to connect the two segments 10 arranged in the axial direction.

A water-swellable linear rubber packing 17 of the same shape is sandwiched between one straight flange 14 and the other straight flange 15 of two circumferentially adjacent segments 10 to form one straight line. A bolt 18 is screwed into the nut 15a from the side of the flange 14 through the bolt hole 14a to connect the two segments 10 arranged in the circumferential direction. Thereafter, the above operation is repeated to lay a circular pipe having the connection of the segments 10 in the existing buried pipe connecting the two manholes. Then, the working window holes 11a, 1a,
A synthetic resin is injected from 1b, and the surface of the synthetic resin inside the window holes 11a and 11b is finished and hardened into the same smooth cylindrical surface as the inner surface of the skin plate 11.

2 to 5 show specific examples of the segment 10. FIG. 2 and 3, a skin plate 11, arcuate flanges 12, 13 and a straight flange 1 are shown.
4 and 15 are formed of a stainless steel plate as described above.
The skin plate 11 has the above-mentioned working window hole 11a along the arcuate flange 12 having a bolt hole (not shown) in a pair of opposing arcuate flanges 12,13.
And a box-shaped cover 21 for covering the
A box-shaped cover 22 is provided along the straight flange 14 having a bolt hole (not shown) in the set of straight flanges 14 and 15 to cover the working window hole 11b.
13a and 15a are nuts similar to the above. In FIG. 3, reference numeral 1 denotes a stratum, and 2 denotes a buried pipe underground.

As shown in FIG. 4, the box-shaped cover 21 along the above-mentioned bow-shaped flange 12 is a part of the bow-shaped flange 12 standing upright on the left edge of the working window hole 11a, the right edge of the above-mentioned window hole 11a, The wall portion 21a which stands upright from the front side edge and the paper back side edge, respectively, and the ceiling portion 21b facing the window hole 11a are formed at the same height as the arc-shaped flanges 12, 13 and the straight flanges 14, 15. . As shown in FIG. 5, the box-shaped cover 22 along the straight flange 14 is a straight flange 1 standing upright on the left edge of the work window 11b.
4, a right side edge of the window hole 11b, a wall portion 22a standing upright from an edge on the near side of the paper surface and an edge on the back side of the paper, and a ceiling portion 22b facing the window hole 11a. And the same height as the arc-shaped flanges 12 and 13.

The segment 10 shown in FIGS.
Are connected in the same manner as the segment 10 in FIG. Then, the synthetic resin is injected from the working window holes 11a and 11b into the inside of the box-shaped covers 21 and 22 where the connection is completed, and the exposed portion seen through the window holes 11a and 11b is the same as the inner surface of the skin plate 11. Finished with a perfect cylindrical surface. In addition, any packing may be inserted between the segment 10 and the existing buried pipe 2 at any time, or the flanges 12 and 1 may be inserted.
The circular pipe composed of the above-mentioned segment 10 is fixed by injecting synthetic resin from the gaps between 3, 14, 15 and the buried pipe 2.

[0020]

According to the method for rehabilitating an underground buried pipe according to the first aspect, a plurality of segments constituting a part of a circular pipe thinner than the buried pipe in the underground buried pipe are circumferentially and longitudinally laid. In the method of rehabilitating a buried pipe in which another circular pipe is laid in the buried pipe in the above-mentioned buried pipe, as the above-mentioned segment, a rectangular plate is radially outwardly directed around four circumferences of a skin plate having a curved cross-sectional shape. A plurality of bolt holes are provided on one of the opposed flanges, and a nut is provided on the other opposite the bolt hole, and a working window hole is provided at an edge of the skin plate on the side where the bolt hole is provided. Is used, a rubber packing is interposed between two adjacent segments, and a bolt is inserted from the inside of the segment through a working window hole to a bolt hole of a flange adjacent to the window hole and an adjacent segment. It is a method of inserting the above bolt into the nut by inserting it into the nut of the lunge, and then closing the working window with synthetic resin. Therefore, it is feasible if the damaged existing buried pipe has an inner diameter of 1 m or more. Compared with the conventional method of sticking tubes inside, large boilers and water supply pumps are not required, which saves equipment costs and makes it possible to easily install a high-strength circular pipe and has a narrow cross-sectional area. Despite this, the flow capacity does not decrease.

According to a second aspect of the present invention, in the first aspect of the present invention, a box-shaped cover for covering the window is formed in advance outside the working window of the segment, and after a bolt is fastened, Since the box-shaped cover is filled with a synthetic resin to close the window, the working window can be easily closed.

The invention described in claim 3 is a method according to claim 1 or 2, wherein the skin plate constituting the segment is formed in a shape obtained by dividing a cylinder into four or more segments. The operation when connecting is further facilitated, and the efficiency is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a plan view of a segment.

FIG. 3 is a cross-sectional view when connecting segments.

FIG. 4 is a sectional view of an axial connection portion of a segment.

FIG. 5 is a sectional view of a circumferential connection portion of a segment.

[Explanation of symbols]

1: geological formation 2: buried pipe underground 10: segment 11: skin plate 11a, 11b: work window hole 12, 13: bow-shaped flange 14, 15: straight flange 12a, 14a:
Bolt holes 13a, 15a: Nuts 16: Bow-shaped rubber packing 17: Straight rubber packing 18: Bolts 21, 22: Box-shaped cover

Claims (3)

(57) [Claims] 1. A plurality of segments forming a part of a circular pipe smaller than the buried pipe are connected in a circumferential direction and a length direction in an underground buried pipe, and another circular pipe is laid in the buried pipe. In the rehabilitation method for buried pipes,
A rectangular plate is provided with a radially outward flange on four sides of a skin plate having a shape curved in an arc cross section, a plurality of bolt holes on one of the opposed flanges, and a nut on the other facing the bolt hole. Each of which has a work window hole opened at the edge of the skin plate on which the bolt hole is provided, and a rubber packing is interposed between two adjacent segments to work from the inside of the segment. A bolt inserted through the window hole into the bolt hole of the flange adjacent to the window hole and the nut of the flange of the adjacent segment and screwing the bolt into the nut, and then closing the work window hole with synthetic resin. Rehabilitation of underground pipes. 2. A box-shaped cover for covering the window hole is formed in advance outside the working window hole of the segment, and after the bolt is fastened, the box-shaped cover is filled with a synthetic resin to close the window hole. The method for rehabilitating underground buried pipes according to item 1. 3. The method according to claim 1, wherein the skin plate is formed in a shape obtained by dividing a cylinder into four or more sections.