1. Field of the Invention
The present invention relates to an apparatus and method for a rehabilitation pipe adapted for use in constructing a rehabilitation pipe for repairing pipeline facilities in which the rehabilitation pipe is assembled by linking segments in the circumferential direction and in the pipe-length direction. The segments each comprise an inner surface plate constituting an inner circumferential surface, and side plates and end plates provided upright on peripheral edges of the inner surface plate, these plates being formed integrally from a plastic material.
2. Description of the Related Art
In cases in which a sewage pipe or another pipeline buried underground has deteriorated through aging, a pipe lining method has been proposed and practiced in which a lining is provided to the inner circumferential surface thereof to repair the pipeline without excavating it from the ground.
JP-A 2010-43731 discloses a method using segments each comprising an inner surface plate constituting an inner circumferential surface, side plates and end plates provided upright on the peripheral edges of the inner surface plate, these plates being integrally formed from a plastic material. The segments are linked in the circumferential direction to provide pipe units, which are then linked in the pipe-length direction to construct a rehabilitation pipe for repairing a pipeline. In the method, some of the segments are divided in the pipe-length direction into two segment halves, which are moved relative to each other in the pipe-length direction to make the width of the segment in the pipe-length direction variable.
After assembling the rehabilitation pipe inside an existing pipe using the segments, a filler is injected between the existing pipe and the rehabilitation pipe. Until the filler becomes hardened, the rehabilitation pipe is supported by a falsework.
A spacer 205 is used to adjust the space between the existing pipe 201 and the rehabilitation pipe 202. A wale 206 that is disposed in the pipe-length direction so as to be in contact with the inner surface of the rehabilitation pipe 202 is supported by a support member 203 that is adjustable in length by jack bases 204 connected at ends thereto.
In cases in which variable-width segments as described in JP-A 2010-43731 are used, such a falsework as shown in
It is therefore an object of the present invention to provide an apparatus and method for supporting a rehabilitation pipe being capable of preventing a filler from leaking when constructing a rehabilitation pipe inside an existing pipe using variable-width segments.
The present invention provides an apparatus and method for supporting a rehabilitation pipe inside an existing pipe since a filler is injected into a space between the rehabilitation pipe and the existing pipe until the filler hardens. The rehabilitation pipe is assembled using integrally formed plastic segments each comprising an inner surface plate, and side and end plates provided upright on a peripheral edge of the inner surface plate. The segments are in part or all divided in the pipe-length direction to provide a variable-width segment comprising two segment halves that are moved relative to each other in the pipe-length direction to make the width of the segment in the pipe-length direction variable. A shape-holing member is disposed circumferentially in part or all over the inner surface of the rehabilitation pipe so as to be in contact with the inner surface plate of the variable-width segment. A support member is provided for directly or indirectly supporting the shape-holding member.
According to the present invention, the shape-holding member is pressed circumferentially against the inner surface plate of the variable-width segment, thereby pressing one segment half against the other segment half. This allows the space between the two segment halves to be shortened, preventing the filler injected from leaking from the segment halves.
a is a plan view showing the structure of an end plate of the segment;
b and 5c are cross-sectional views each showing a variable-width segment;
a and 8b are illustrative views each showing a falsework when using a variable-width segment;
a through 9d are cross-sectional views each showing a variable-width segment and a falsework;
a and 12b are cross-sectional views each showing the seams of an existing pipe and a variable-width segment;
a and 14b are illustrative views each showing a conventional falsework.
The present invention will now be described with references to embodiments illustrated in the accompanying drawings. The present invention is suitable for rehabilitating or repairing large-diameter existing pipes such as sewage pipes, water supply pipes, tunnels, and agricultural irrigation channels. In the present embodiment, the rehabilitation pipes are described as having a circular cross-section profile orthogonal to the pipe-length direction. However, it shall be apparent that the present invention can be applied to a rehabilitation pipe having a square or another non-circular cross-section.
In the present specifications, the pipe-length direction refers to the direction indicated by arrow X extending in the longitudinal direction of a pipe unit 10 in
According to one embodiment of the present invention, a pipe unit 10 and a variable-width pipe unit 11 are linked in the pipe-length direction to construct a rehabilitation pipe 20 inside an existing pipe 21 having a circular cross-section as shown in
As shown in
In the present embodiment, the segment 1 has a shape that is curved as an arc representing a predetermined angle that equally divides the circumference, e.g., a 72° arc that divides the circumference into fifths. However, the segment is not limited to that having an arc or a fan shape. The segment may be shaped as, e.g., a cuboid or a shape that is bent so as to have a curved right angle depending on the cross-section profile or the size of the existing pipe or the location of the existing pipe to be repaired.
A plurality of inner plates 106, 107 (two inner plates 106 and two inner plates 107 in the present embodiment) having a shape similar to that of the side plates are provided upright at equal intervals and parallel to the side plates 102, 103 on the upper surface of the inner surface plate 101 and on the inside relative to the side plates 102, 103 in order to reinforce the mechanical strength of the segment 1.
The inner surface plate 101, the side plates 102, 103, the end plates 104, 105, and the inner plates 106, 107 are all made from an identical transparent, semi-transparent or opaque plastic material, and are integrally formed using a known molding technique.
A plurality of holes 102a and 103a for admitting insertion of a metallic member for linking the segment 1 in the pipe-length direction are provided at equal intervals along the circumference in the side plates 102 and 103. The holes 102a in the side plate 102 and holes 103a in the side plate 103 are located at coinciding positions along the circumferential direction. Similarly, the inner plates 106 are provided with holes 106a and the inner plates 107 are provided with notches 107a.
a is a detailed view of the end plate 105. The following descriptions are given in relation to the end plate 105, but the end plate 104 also has a configuration similar to that of the end plate 105.
The end plate 105 is a rectangular thin-plate member arranged between the side plate 102 and the side plate 103. The height of the end plate 105 from the outer surface of the inner surface plate 101 is slightly lower than that of the side plates 102, 103. Circular insertion holes 105a for admitting insertion of a bolt for linking the segment 1 in the circumferential direction are provided on the end plate 105 between the side plate 102 and an inner plate 106, between the inner plate 106 and an inner plate 107, between the two inner plates 107, between the inner plate 107 and an inner plate 106, and between the inner plate 106 and the side plate 103.
The variable-width segment 2 has a structure that is substantially similar to that of the segment 1, but is comprised of two segment halves so as to be variable in width in the pipe-length direction.
The variable-width segment 2 is composed of a segment half 3 and a segment half 4. The segment half 3 is configured from an inner surface plate 301, a convex plate 302, a side plate 303, inner plates 304, 305, and the like. The plates 301 to 305 are all integrally molded using the same plastic material as the segment 1. The convex plate 302 extends parallel to and at a different height from the inner surface plate 301. The side plate 303, and inner plates 304, 305 extend perpendicular to the inner surface plate 301.
The segment half 4 is configured from an inner surface plate 401, a side plate 403, inner plates 402, 404, 405, and the like. The plates 401 through 405 are all integrally molded using the same plastic material as the segment 1. The side plate 403 and the inner plates 404, 405 extend perpendicular to the inner surface plate 401, and the inner plate 402 extends parallel to the inner surface plate 401.
Formed in the side plate 403 is a protuberance 403a for fitting with the holes 102a, 103a in the side plates 102, 103 of the segment 1, or with the hole 303a in the segment half 3.
A concavity 407 for fitting with the convex plate 302 of the segment half 3 is formed by the inner plates 402, 405 and the inner surface plate 401.
The overlap of the convex plate 302 with the inner surface plate 401 in the concavity 407 is varied between d+a in
In
The segment half 7 is configured from an inner surface plate 701, a side plate 703, inner plates 704, 705, and the like. The plates 701 through 705 are all integrally molded using the same plastic material as the segment 1. The side plate 703 and the inner plates 704, 705 extend perpendicular to the inner surface plate 701.
The segment halves 6, 7 configured in this manner are moved so that the convex plate 602 of the segment half 6 and the inner surface plate 701 of the segment half 7 are made to overlap by sliding the ridge 602a of the convex plate 602 through the concavity 701a of the segment half 7. In other words, the overlap width d2 in
Since the segment halves 6, 7 are merely superposed together, they are likely to move in the radial direction and separate. Therefore, after the positions in the segment width direction are adjusted, the segment halves 6, 7 are preferably temporarily bonded or temporarily joined in a superposed state. When the existing pipe and the rehabilitating pipe are integrated by the filler injected between the two, the segment halves 6, 7 can no longer move, and accordingly there is no danger of the segment halves moving in the radial direction.
A description will now be given for a method for rehabilitating an existing pipe using the segments 1 and the variable-width segments 2, 5 configured as described above. First, as shown in
Next, the pipe units 10 and the variable-width pipe units 11 are sequentially linked in the pipe-length direction to construct the rehabilitation pipe 20 inside the existing pipe 21.
If the diameter of the rehabilitation pipe is large, the segments 1 and the variable-width segments 2, 5 that have been carried in can be transported to the location of actual installation, and the segments 1, 2, 5 are linked in the circumferential direction and in the pipe-length direction at this location.
Next, a filler such as grout is injected into a space 22 (see
The injected filler allows the existing pipe 21 and the rehabilitation pipe 20 to be solidly bound to create a composite pipe comprising the existing pipe, the filler, and the rehabilitation pipe.
a and 8b show a falsework for temporarily supporting the rehabilitation pipe 20 until the filler is hardened. The rehabilitation pipe 20 is installed with its center deviating downwards relative to the center of the existing pipe 21. Therefore, a spacer 35 is inserted into sections of a large gap between the tip of the side plates 102 (outer circumference surface of the rehabilitation pipe 20) and the inner circumference surface of the existing pipe 21 in order to resist against buoyancy of the filler and maintain a positional relationship of the rehabilitation pipe 20 relative to the existing pipe 21.
An annular shape-holding member 40 is disposed over the entire circumference of the rehabilitation pipe 20 at locations at which the variable-width pipe units 11 are disposed. The shape-holding member 40 is divided into four pieces in the circumferential direction considering workability, and is fabricated so as to fit to the shape of the inner surface of the rehabilitation pipe 20 by bending shape steel such as a square pipe steel. The shape-holding member 40 doesn't necessarily need to be disposed over the entire circumference of the rehabilitation pipe, and may be disposed merely at locations at which the filler is likely to leak depending on the cross-sectional shape of the rehabilitation pipe 20.
A wale 36 is disposed in the pipe-length direction so as to come into contact with the inner surface of the shape-holding member 40. Two pairs of wales 46, i.e., four wales in total are disposed at locations symmetrical relative to the cross-sectional center of the rehabilitation pipe 20. Each pair of wales 46 are supported by a support member 33 made of a pipe or a rod member. The support member 33 indirectly supports the shape-holding member 40 via the wale 36. A jack base 34 is connected to both ends of the support member 33 to adjust the length thereof in the radial direction. A method for supporting the shape-holding member 40 is not limited to the example as shown in
a shows in detail a section at which the shape-holding member 40 comes into contact with the variable-width segment 2 via a cushion 43 or without any cushion.
In the following, the example of no cushion will be described. The shape-holding member 40 is a square pipe in cross-section comprising four integrated plates, one of which 40a is in contact with the inner surface plate of the variable-width segment 2, i.e., the inner surface plate 301 of the segment half 3 and the inner surface plate 401 of the segment half 4. The shape-holding member 40 is disposed in the pipe-length direction so as to come into contact with a section at which the segment half 3 overlaps with the segment half 4 (hereinafter, referred to as an overlap section), for example, a section indicated by the numerical symbol 51 in
As shown by the numerical symbol 50 in
The shape-holding member 40 may be L-shaped in cross-section, as shown in
The shape-holding member 40 may also be circular in cross-section, as shown in
According to the present embodiment, the shape-holding member 40 is disposed so as to come into contact with at least the inner surface plate 401 (701) of the segment halves 3, 4 (6, 7), so that the inner surface plate 401 (701) is pressed against the convex plate 302 (602). Therefore, the inner surface plate 401 (701) and the convex plate 302 (602) come into close contact with each other with the gap between both the plates being reduced, allowing the filler to be less likely to leak. The shape-holding member 40 is ring-shaped, so that it comes into contact with the entire inner circumferential surface of the variable-width pipe unit 11, and the above-mentioned advantages are obtained all over the circumference thereof.
The location at which the shape-holding member 40 is disposed is not limited to the overlap section 51 of the inner surface plate 401 (701), but bringing the shape-holding member 40 into contact with the overlap section 51 ensures that the inner surface plate 401 (701) is pressed against the convex plate 302 (602).
In cases where the shape-holding member 40 is disposed so as to plug the gap section 50, the possible exit from which the filler leaks can be plugged, ensuring that the filler is prevented from leaking.
The shape-holding member 40 also holds the cross-sectional shape of the rehabilitation pipe 20. This enhances the function of the spacer 35 that is inserted between the existing pipe 21 and the rehabilitation pipe 20. In particular, in cases where the rehabilitation pipe is rectangular and non-circular in cross-section, the function of the spacer 35 is enhanced, allowing the spacer to be prevented from positional deviation.
The shape-holding member 40 may be shaped other than ring-shaped.
A description was given for the embodiment in which the variable-width segment is used to adapt to the bend of the existing pipe. Another embodiment will be described in which the variable-width segment is used to provide a rehabilitation pipe with enhanced earthquake resistance. The structure of the rehabilitation pipe is substantially the same as that in the above-mentioned embodiment, so that components identical to those in the above-mentioned embodiment are denoted by the same numerical symbols and are not described in detail.
a shows in cross-section a variable-width segment 8 constituting the variable-width pipe unit 12. The variable-width segment 8 has an arrangement similar to that of the variable-width segment 2 in
A great amount of tension acts on the existing pipe 21 when an earthquake occurs, and the seams 26 thereof separate. In such a case, the segment halves 81, 82 are moved to each other in the pipe-length direction so as to separate, enlarging the width of the variable-width segment 8, as shown in
This embodiment also provides the effect similar to that of the previous embodiment. In other words, the shape-holding member 40 presses the inner surface plate 821 against the convex plate 812, which is pressed against the braking member 9, which is then pressed against the inner plate 822. Therefore, the inner surface plate 821 and the convex plate 812; the convex plate 812 and the braking member 9; and the braking member 9 and the inner plate 822 are brought into close contact with each other, thus allowing the filler to be prevented from leaking.
Number | Date | Country | Kind |
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2013-155217 | Jul 2013 | JP | national |