JP7620526B2 - Device and method for preventing floating of rehabilitated pipes during existing pipe rehabilitation work - Google Patents

Description

This invention relates to technology for rehabilitating existing pipes, such as aging sewer pipes.

A widely known method for rehabilitating existing pipes, such as aging sewer pipes, is to line the inside of the existing pipe with a rehabilitating pipe and fill the gap between the outer surface of the rehabilitating pipe and the inner surface of the existing pipe with backfill material such as cement milk or mortar. When filling the backfill material, buoyancy is applied to the rehabilitating pipe, so it is common to carry out anti-floating work to prevent the rehabilitating pipe from floating up.

Meanwhile, in recent years, localized heavy rains known as "guerilla downpours" have become more frequent in urban areas, and flooding damage caused by water overflowing from manholes has become a problem in sewer systems. For pipelines with high flow rates, a construction method is used in which the pipeline is rehabilitated while sewage is still flowing, but construction while the pipeline is in service carries the risk of rising water levels in the pipe and overflow due to rainfall. This risk is particularly high during flood seasons when torrential rains are more frequent. Therefore, there is a demand for a rehabilitation method that can reduce flow obstruction during construction. One method known to be a floating prevention method that can reduce flow obstruction is to install a floating prevention support member between the rehabilitated pipe and the existing pipe.

Patent documents 1 and 2 describe a method in which a support member is installed on the outer periphery of the rehabilitated pipe, the support member is abutted against the inner periphery of the existing pipe, and then a backfilling material is filled between the existing pipe and the rehabilitated pipe.
Patent Document 3 discloses a plate-shaped support member curved in an arc shape. A plurality of spacing members are provided on the support member at intervals in the circumferential direction of the support member. The spacing members are made of coil springs, bolts, and nuts. The support members are inserted between the lined rehabilitating pipe and the existing pipe, and are arranged along the circumferential direction of the outer periphery of the rehabilitating pipe, and the tip of each spacing member is abutted against the inner periphery of the existing pipe. A plurality of support members are arranged at intervals in the extension direction of the existing pipe and the rehabilitating pipe. Then, backfilling material is filled between the existing pipe and the rehabilitating pipe. The support members prevent the rehabilitating pipe from floating up.
Patent Document 4 describes a method of installing a support member consisting of a perforated curved plate at the top of the existing pipe, lining the rehabilitated pipe, and then filling the space between the rehabilitated pipe and the existing pipe with backfill material.
Patent Document 5 describes a method of preventing the rehabilitated pipe from floating up by placing a support member made of a cylindrical mesh material on the top of the existing pipe before or after the production of the rehabilitated pipe, injecting cement into the cylindrical support member and causing it to expand, and then filling the space between the existing pipe and the rehabilitated pipe with backfill material.

JP 2018-109433 A JP 2019-27594 A JP 2016-188671 A Japanese Patent Application Publication No. 7-100925 JP 2009-133477 A

The support members disclosed in Patent Documents 1 to 3 must be brought into the pipe and installed in parallel with the lining of the rehabilitated pipe, which increases the obstruction of flow during construction and may cause the constituent members of the rehabilitated pipe and the support members to be washed away. In the rehabilitation construction method of Patent Document 4, support members made of curved perforated plates are installed before lining the rehabilitated pipe, which can reduce the obstruction of flow during lining construction, but since the rehabilitated pipe is manufactured to fit support members of a certain shape and size, the cross section of the manufactured rehabilitated pipe is likely to differ from the design cross section used in strength calculations, and if the corrosion of the existing pipe is locally large, this may affect the safety of the structure.
In the rehabilitation construction method of Patent Document 5, by installing a tubular support member after lining the rehabilitation pipe, it is possible to reduce flow obstruction during lining construction; however, in places where the existing pipe is misaligned, there is no gap between the rehabilitation pipe and the existing pipe, making it difficult to install and expand the tubular support member after lining the rehabilitation pipe.
In consideration of the above circumstances, the present invention aims to provide an anti-floating device and method that can be installed without being hindered even if the existing pipe is uneven, can reduce flow obstruction during installation, and can ensure the finished shape of the rehabilitated pipe.

In order to solve the above problem, the present invention provides a floating prevention device that prevents a rehabilitating pipe from floating up when filling a backfilling material in a pipe-to-pipe space between a rehabilitating pipe lined along the inner circumference of an existing pipe and the existing pipe,
A linear support beam material along the extension direction of the existing pipe;
An attachment means for attaching the support beam to an inner peripheral surface of an upper half of the existing pipe in a manner that allows the support beam to move toward and away from the inner peripheral surface of the upper half of the existing pipe;
Interposition members are interposed in the gap between the supporting beam material and the existing pipe with an amount of interposition adjustable according to the gap, and are arranged apart from each other in the longitudinal direction of the supporting beam material;
The present invention is characterized by comprising:
The supporting beam material, the fastening means and the intermediate member constitute the supporting member.

According to the floating prevention device having the above characteristics, the installation work of the floating prevention device can be carried out prior to lining the rehabilitated pipe. Furthermore, since the supporting beam material is linear along the extension direction of the inner surface of the upper half of the existing pipe, the cross-sectional ratio of the beam material to the cross section of the pipe is small, and downstream obstruction can be reduced. When there is an uneven part in the existing pipe, the arrangement of the supporting beam material is adjusted, or the amount of installation of the multiple intermediate members is adjusted to adjust the distance (arrangement height) and inclination (angle) of the supporting beam material relative to the inner surface of the existing pipe. Therefore, even if the existing pipe is uneven, it does not hinder the installation.
Then, the supporting beam material is moved toward and away from the inner circumferential surface of the existing pipe so that it rests on the rehabilitated pipe. Therefore, rather than making the shape of the rehabilitated pipe to follow the supporting beam material, the placement height of the supporting beam material can follow the rehabilitated pipe, ensuring the finished shape of the rehabilitated pipe. The amount of insertion of each interposing member is adjusted so that the supporting beam material comes into contact with the existing pipe when the supporting beam material is placed on the rehabilitated pipe, or so that each interposing member fills the gap between the existing pipe and the supporting beam material. When the supporting beam material comes into contact with the existing pipe, the amount of insertion is adjusted to zero. This allows the rehabilitated pipe to be held down from above by the supporting beam material when filling the backfill material, preventing the rehabilitated pipe from floating up.

The attachment means preferably includes rod-shaped attachment bodies such as concrete screws that are arranged at intervals along the longitudinal direction of the support beam and attach to the existing pipe. This allows the support beam to be stably attached to the existing concrete pipe and be movable toward and away from it. If the existing pipe is uneven, the support beam can be aligned with the rehabilitated pipe and installed at an angle to a portion of the existing pipe.

Preferably, the plurality of interposing members include a plurality of protruding and retracting members that can protrude from and retract into the surface of the support beam facing the existing pipe, and the amount of protrusion of the protruding and retracting members from the facing surface is provided as the interposing amount. This allows easy adjustment by contacting the protruding and retracting members with the existing pipe.

It is preferable that each of the plurality of projecting and retracting members is constituted by a screw, and that the supporting beam member has a plurality of female screw holes into which the screws are screwed, the female screw holes being spaced apart from each other in the longitudinal direction. This allows the projecting and retracting members to be projected and retracted from the supporting beam member by a screw-turning operation.
Preferably, when installing the floating prevention device on an existing pipe, each of the protruding and retracting members is retracted into the supporting beam material, and then the protruding amount of each of the protruding and retracting members is adjusted according to the cross section of the rehabilitated pipe to be lined and the presence or absence of unevenness in the existing pipe, etc. This ensures the finished shape of the rehabilitated pipe and prevents the rehabilitated pipe from floating up when filling with backfill material.

At least one of the multiple interposing members may be configured as an adjustment plate whose number is adjusted according to the gap, and the stacked amount of the adjustment plates may be provided as the interposing amount. In this way, by replacing a part of the protruding member with an adjustment plate, the work of filling the gap between the support beam material and the existing pipe can be easily performed. In addition, since the adjustment plate can have a larger contact area with the existing pipe than the protruding member, it can effectively withstand the load from the rehabilitated pipe when filling the backing material, and damage to the existing pipe can be avoided.

It is preferable that the pipe has a plurality of support beams each extending along the extension direction and arranged spaced apart from each other circumferentially of the upper half of the existing pipe, and each longitudinal portion of each support beam is constituted by the support beam material.
In this way, the floating of the rehabilitating pipe can be stably prevented. Adjacent support beam members in each support beam may be spaced apart in the extension direction, may be slightly offset in the circumferential direction of the pipe, or may be arranged at an angle to each other.

The present invention is a method for preventing floating of a rehabilitating pipe when filling a backfilling material into a space between an existing pipe and a rehabilitating pipe lined along the inner circumference of the existing pipe, the method comprising the steps of:
Prior to lining the rehabilitating pipe, a linear support beam material extending in an extension direction of the existing pipe is attached to an inner peripheral surface of an upper half of the existing pipe by an attachment means so as to be movable toward and away from the inner peripheral surface of the upper half of the existing pipe;
The method is characterized in that the support beam material is moved closer to and farther away from the existing pipe so that it rests on the rehabilitated pipe, and the amount of interposition is adjusted so that the support beam material contacts the existing pipe or so that a plurality of interposition members arranged at a distance in the longitudinal direction of the support beam material fill the gap between the support beam material and the existing pipe.
According to this method, by installing the anti-floating device prior to lining the rehabilitated pipe, flow obstruction is reduced and the anti-floating device can be installed reliably. In addition, the intervening member is interposed between the supporting beam material and the existing pipe to follow the unevenness of the existing pipe, while the supporting beam material can be installed to follow the rehabilitated pipe regardless of the unevenness. Therefore, the finished shape of the rehabilitated pipe can be ensured. And, when filling the backfill material, the rehabilitated pipe can be pressed down from above by the supporting beam material, preventing the rehabilitated pipe from floating up.

It is preferable to adjust the amount of interposition when or immediately before lining the rehabilitating pipe directly below or to the side of the supporting beam material, so that the supporting beam material can reliably follow the rehabilitating pipe being lined, and the amount of interposition of the interposition member (the protruding amount of the protruding member in the case of using a protruding member) can reliably follow the unevenness of the existing pipe.
Preferably, the height or thickness of the supporting beam is set according to the minimum gap amount in the pipe axial direction of the angle portion where the supporting beam is placed in the inter-pipe space between the existing pipe and the rehabilitated pipe. This allows the supporting beam to abut the inner peripheral surface of the existing pipe when placed on the rehabilitated pipe at the minimum gap location. This eliminates the need to use an intervening member (if a protruding member is used, it is not necessary for the protruding member to protrude from the supporting beam, and the protrusion amount is adjusted to zero).

A pipe rehabilitation tool having a length substantially equal to the diameter of the pipe is prepared.
Prior to the lining, with the base end of the rehabilitation pipe substitute jig abutted against the bottom of the existing pipe, the support beam material is placed on the tip of the rehabilitation pipe substitute jig while moving it closer to and away from the existing pipe, and the amount of interposition is adjusted so that the support beam material abuts against the existing pipe or the interposition member fills the gap between the support beam material and the existing pipe.
Thereafter, the rehabilitating pipe is lined and a support beam is placed on the rehabilitating pipe. Then, the support beam comes into contact with the existing pipe or the intermediate member comes into contact with the existing pipe.
Even in this case, the support beam material may be moved closer and farther away again when or immediately before the rehabilitation pipe is lined directly below or to the side of the support beam material, and the amount of spacing of each spacing member may be readjusted or fine-tuned.

Alternatively, after the lining, the rehabilitated pipe may be tensioned in the vertical direction or in the pipe diameter direction connecting the supporting beam material and the part 180° opposite it. For example, a tensioning jig is placed inside the rehabilitated pipe and extended in the vertical direction or in the pipe diameter direction. This ensures that when the rehabilitated pipe is deformed so as to be flattened by its own weight, the shape of the rehabilitated pipe can be corrected to ensure the finished shape. It also ensures that the rehabilitated pipe hits the supporting beam material and that the supporting beam material or the protruding member hits the existing pipe, which reliably prevents the rehabilitated pipe from floating up when the backfill material is filled.

According to the present invention, the anti-floating device can be installed without any problems even if the existing pipe is uneven. It also reduces the obstruction of flow during installation. Furthermore, the finished shape of the rehabilitated pipe can be ensured.

FIG. 1 shows an existing pipe that has been rehabilitated using an anti-floating device according to a first embodiment of the present invention, and is a front cross-sectional view taken along line II in FIG. 2 is a side cross-sectional view of the rehabilitated existing pipe taken along the bend line II-II in FIG. 1. FIG. 3 is an exploded perspective view of a support member of the anti-floating device. FIG. 4 is a bottom view of the support member taken along line IV-IV in FIG. FIG. 5 is a cross-sectional view of the support member taken along line VV in FIG. FIG. 6 is a side cross-sectional view of the upper half of the existing pipe, showing the rehabilitation work for the existing pipe during the installation process of the anti-floating device. FIG. 7(a) is an enlarged cross-sectional view of the circled portion VIIa in FIG. 2, showing the rehabilitation work for the existing pipe in the lining process of the rehabilitating pipe. FIG. 7(b) is an enlarged cross-sectional view of a circled portion VIIb in FIG. 2, showing the rehabilitation work for the existing pipe in a lining process for the rehabilitating pipe. FIG. 8 is a side cross-sectional view of the upper half of the existing pipe, illustrating the lining process when the existing pipe has a concave uneven portion. FIG. 9 is a side cross-sectional view of the existing pipe, illustrating the lining process when the existing pipe has a stepped uneven portion. FIG. 10 is an exploded perspective view of a support member according to a second embodiment of the present invention. FIG. 11 is an exploded perspective view of a support member according to a third embodiment of the present invention. FIG. 12 is an exploded perspective view of a support member according to a fourth embodiment of the present invention. FIG. 13 is an exploded perspective view of a support member according to a fourth embodiment of the present invention. FIG. 14 shows a sixth embodiment of the present invention, and is a side sectional view of a connection portion between adjacent support members. FIG. 15 shows a seventh embodiment of the present invention and is a cross-sectional view of an existing pipe in a process of adjusting the placement height of the supporting beam material and the protrusion amount of the protruding member. FIG. 16 shows an eighth embodiment of the present invention and is a cross-sectional view of an existing pipe in a process of adjusting the placement height of the supporting beam material and the protrusion amount of the protruding member. FIG. 17(a) is a side cross-sectional view of a floating prevention device according to a ninth embodiment of the present invention, showing a state before an adjustment step, and FIG. 17(b) shows the adjustment step. 18(a) is a cross-sectional view taken along line AA in FIG. 17(a), and FIG. 18(b) is a cross-sectional view taken along line BB in FIG. 17(b). Figure 19(a) is a top view of a supporting beam material used in the ninth embodiment, Figure 19(b) is a top view showing a modified supporting beam material used in the same embodiment, and Figure 19(c) is a top view showing a further modified supporting beam material. FIG. 20(a) is a cross-sectional view of an adjusting plate used in the ninth embodiment, and FIG. 20(b) is a bottom view of the adjusting plate. FIG. 21 is a cross-sectional view showing a modified example of the adjustment plates in a stacked state.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First embodiment (FIGS. 1 to 9)
1 and 2 show a rehabilitated existing pipe 1. The existing pipe 1 is a sewer pipe buried underground, but is not limited thereto and may be a water supply pipe, an agricultural irrigation pipe, a hydroelectric power generation water pipe, a gas pipe, or a tunnel. A rehabilitation pipe 3 is lined along the inner circumference of the deteriorated existing pipe 1. An annular inter-pipe space 2 is formed between the existing pipe 1 and the rehabilitation pipe 3. The inter-pipe space 2 is filled with a backfill material 4.

When the backfill material 4 is filled, buoyancy acts on the rehabilitated pipe 3, causing it to rise up. To prevent this, a floating prevention device 5 is installed between the upper half of the existing pipe 1 and the rehabilitated pipe 3.

As shown in FIG. 1, the floating prevention device 5 includes a plurality of support beams 9 installed along the inner peripheral surface of the existing pipe 1. As shown in FIG. 2, the support beams 9 extend along the extension direction (left-right direction in FIG. 2) of the existing pipe 1 and the rehabilitated pipe 3. As shown in FIG. 1, the plurality of support beams 9 are arranged spaced apart from each other in the circumferential direction of the upper half of the existing pipe 1. Preferably, two support beams 9 are installed close to each other on either side of the top of the existing pipe 1.

The support beams 9 may be disposed on the upper half of the existing pipe 1, i.e., on the inner peripheral surface of the arch portion above both sides in the width direction of the existing pipe 1. More specifically, the support beams 9 may be disposed within a range of ±90° with the pipe top of the existing pipe 1 being 0°. However, the pipe top (0°) should be avoided. This makes it possible to prevent the rehabilitating pipe 3 from rotating around the support beam at the pipe top as a fulcrum when it is subjected to buoyancy.
Preferably, at least one pair of support beams 9 is disposed in the range of 0° to ±45°. This makes it possible to effectively counter the buoyancy of the rehabilitation pipe 3.
More preferably, the support beams 9 are arranged at angles as close as possible to ±45° as shown in Figure 1. This reduces stress when earth pressure is applied, and reduces the risk of cracks starting near the support members.

As shown in Fig. 2, each support beam 9 is divided in the longitudinal direction into a plurality of support members 10. The support beam 9 is formed by arranging a plurality of support members 10 in a row. As shown in Figs. 3 to 5, each support member 10 includes a support beam material 11, an engagement means 20, and a projecting and retracting member 30 (intervening member).
In other words, the anti-floating device 5 comprises a support beam material 11, an engagement means 20, and a retractable member 30.

As shown in Fig. 4, the supporting beam material 11 is formed in a straight line along the extension direction of the existing pipe 1. The supporting beam material 11 is made of, for example, flat steel material (flat bar). The length of the supporting beam material 11 is, for example, about 1000 mm to 2000 mm. The width of the supporting beam material 11 is, for example, about 25 mm to 150 mm. As shown in Figs. 1 and 2, the height dimension _h11 connecting the existing pipe facing surface 11a and the rehabilitating pipe facing surface 11b of the supporting beam material 11 is set to be equal to the minimum gap amount _d2 in the pipe axial direction of the angle portion where the supporting beam material 11 is arranged in the inter-pipe space 2, and is, for example, about 15 mm to 100 mm.

As shown in FIG. 2, a plurality of support beam materials 11 are arranged in a row in each support beam 9. In other words, each longitudinal portion of the support beam 9 is composed of a support beam material 11.

As shown in FIG. 5, the support beam material 11 has a pair (two) of insertion holes 12 and a number of female screw holes 13. The insertion holes 12 are arranged at both ends of the support beam material 11 and penetrate the support beam material 12 vertically. As shown in FIG. 4 and FIG. 5, each insertion hole 12 has an annular step 12d, and the second hole portion 12b above the step 12d has a smaller diameter than the first hole portion 12a below. The inner diameter of the first hole portion 12a is preferably about 8 mm to 15 mm. The inner diameter of the second hole portion 12b is preferably about 5 mm to 7 mm. The axial length of the hole portion 12b along the vertical direction is shorter than the axial length of the hole portion 12a.

As shown in FIG. 5, a plurality of female screw holes 13 are formed in the support beam material 11 in the portion inside the pair of insertion holes 12. The multiple female screw holes 13 are formed spaced apart from one another in the longitudinal direction of the support beam material 11. The arrangement pitch of the female screw holes 13 is preferably about 200 mm to 1000 mm. Each female screw hole 13 penetrates the support beam material 11 from top to bottom. A female screw is formed on the inner peripheral surface of the female screw hole 13.

As shown in Fig. 3, each support beam 11 is provided with an attachment means 20 and a projecting member 30. The attachment means 20 includes a pair of concrete screws 21 (rod-shaped attachment bodies). As shown in Fig. 6, each concrete screw 21 is inserted into the corresponding insertion hole 12 from below. The tip of the concrete screw 21 protrudes upward from the support beam 11 and is driven into the concrete constituting the existing pipe 1. The head 21b of the concrete screw 21 protrudes from the inner peripheral surface of the existing pipe 1 into the space inside the pipe. The protruding amount of the concrete screw head 21b is slightly smaller than the height _h11 of the support beam 11 (Fig. 1). The step 12d is hooked on the concrete screw head 21b, so that both longitudinal ends of the support beam 11 are attached to the existing pipe 1. This allows the support beam material 11 to move closer to or away from (raise and lower) the inner surface of the upper half of the existing pipe 1 by the amount of protrusion of the concrete screw head 21b.

As shown in FIG. 3, each of the retractable members 30 is composed of a headless enamel set (set screw, locking screw). Preferably, the tip of the retractable member 30 is flat. The nominal screw diameter of the retractable member 30 is preferably M10 to M20. A plurality of retractable members 30 are arranged spaced apart from each other in the longitudinal direction of the support member 11 and are screwed into the corresponding female screw holes 13. As shown in FIG. 5, the screw-driving operation part 31 of the retractable member 30 (enamel set), such as a hexagonal hole or a slot, is directed downward. The length of the retractable member 30 is equal to or less than the height (vertical dimension) of the support beam material 11. Therefore, the entire retractable member 30 can be accommodated inside the support beam material 11. By operating the screw-driving operation part 31, each of the retractable members 30 can be retracted from the existing pipe facing surface 11a of the support beam material 11.

Using the above-mentioned anti-floating device 5, the existing pipe 1 is rehabilitated as follows.
As shown in Fig. 6, the installation work of the floating prevention device 5 is performed prior to lining (pipe manufacturing) of the rehabilitation pipe 3. In detail, the support beam material 11 is arranged on the inner peripheral surface of the upper half of the existing pipe 1 with the longitudinal direction of the support beam material 11 aligned with the extension direction of the existing pipe 1. Concrete screws 21 are inserted into the insertion holes 12 at both ends of the support beam material 11, and the tips of the concrete screws 21 are driven into the existing pipe 1. When the concrete screws 21 are driven halfway, the driving is stopped to engage the heads 21b with the step 12d, and the support beam material 11 is released below the upper half of the existing pipe 1 and suspended. As a result, the support beam material 11 is engaged with the existing pipe 1 via the concrete screws 21 so as to be able to approach and separate (rise and fall).

In this state, the distance between the inner peripheral surface of the existing pipe 1 and the existing pipe facing surface 11a of the supporting beam material 11 is set to be equal to or less than the height of the supporting beam material 11 and equal to or less than the length of the protruding member 30. In other words, a gap is provided between the supporting beam material 11 and the existing pipe 1 by a height that allows the protruding member 30 to protrude upward from the supporting beam material 11.
Preferably, each of the retractable members 30 is recessed within the support beam 11 .

A plurality of supporting beam materials 11, and thus supporting members 10, are lined up in a row in the extension direction to form a supporting beam 9. Furthermore, two supporting beams 9 are installed in the upper half of the existing pipe 1 on both sides, sandwiching the top of the existing pipe 1 therebetween.
By installing the support beams 9 and thus the anti-floating device 5 prior to lining the rehabilitated pipe 3, downstream obstruction can be reduced compared to when they are installed in parallel with lining. Furthermore, the support beam material 11 of the anti-floating device 5 is linear along the extension direction of the inner circumferential surface of the upper half of the existing pipe 1, and occupies a small cross-sectional area in the cross section of the pipe, further reducing downstream obstruction. This allows the anti-floating device 5 to be installed reliably.

As shown in Figures 7(a) and 7(b), the rehabilitated pipe 3 is then lined. The rehabilitated pipe 3 is manufactured to meet the required or designed strength and cross section. At this time, the support beam material 11 is moved closer to and away from the upper half of the existing pipe 1 (raised and lowered) so that it rests on the upper half of the rehabilitated pipe 3 during lining (manufacturing). In effect, the support beam material 11 is pushed up and brought closer to the inner surface of the upper half of the existing pipe 1. Therefore, the height of the support beam material 11 can be adjusted to follow the rehabilitated pipe 3, and the finished shape of the rehabilitated pipe 3 can be ensured. The moving closer and farther operation (raising and lowering operation) of the support member 11 may be performed simultaneously with the lining of the rehabilitated pipe 3 directly below or to the side of the support beam material 11, or may be performed immediately before that.

When the support member 11 is placed on the rehabilitation pipe 3, the existing pipe facing surface 11a of the support beam material 11 comes into contact with the existing pipe 1 (FIG. 7(a)), or a gap 2a is formed between the existing pipe facing surface 11a of the support beam material 11 and the inner peripheral surface of the existing pipe 1 (FIG. 7(b)). As shown in FIG. 7(b), when the gap 2a is formed, the projecting member 30 is projected upward from the support beam material 11 by fitting a tool such as a hexagonal wrench 6 into the screw driving operation part 31 of each of the projecting members 30 and turning it, so that the tip of the projecting member 30 abuts against the inner peripheral surface of the existing pipe 1. The projection amount of the multiple projecting members 30 of the support beam material 11 (the amount of insertion into the gap between the existing pipe 1 and the support beam material 11) is adjusted individually so that the tip of each projecting member 30 abuts against the existing pipe 1. This causes the support beam material 11 to be sandwiched and fixed between the existing pipe 1 and the rehabilitated pipe 3.
The adjustment of the amount of protrusion of the protruding member 30 may be performed in parallel with the raising and lowering operation of the support member 11, when the rehabilitation pipe 3 is lined directly below or to the side of the support beam material 11, or may be performed immediately before lining.

As shown in Figures 2 and 8, when the existing pipe 1 has a concave uneven portion 1c caused by corrosion or the like, the support beam material 11 is arranged straight along the pipe axis _L3 regardless of the uneven portion 1c, and each protruding member 30 is abutted against the inner surface of the existing pipe 1 by adjusting the protrusion amount (projection allowance) to match the uneven portion 1c.
By using a headless hollow set screw (set screw, locking screw) as the protruding member 30, the amount of protrusion (extension) from the support beam material 11 can be made large.
By making the length of the protruding member 30 equal to or less than the height dimension _h11 of the support member 11, it is possible to prevent the protruding member 30 from protruding from the rehabilitating pipe facing surface 11b of the support member 11, and to prevent the rehabilitating pipe 3 from being damaged by contact with the protruding member 30.

As shown in Figure 9, when a stepped uneven portion 1d is formed in the existing pipe 1 due to a step misalignment or the like, the peripheral portion 3d of the uneven portion 1d in the rehabilitation pipe 3 is manufactured at an angle to the pipe axis _L3 in front of and behind the uneven portion 1d. In accordance with this, the supporting beam material 11 of the supporting member 10A on the inner surface 1a of the existing pipe on the relatively upwardly recessed side across the uneven portion 1d is installed at an angle to the inner surface 1a of the existing pipe.

That is, the protruding amount of the multiple protruding members 30 of the support member 10A is made different from one another. Specifically, the protruding amount of the protruding member 30 closer to the uneven portion 1d is made larger, and the tip of each protruding member 30 is abutted against the inner surface 1a of the existing pipe. This causes the support beam material 11 of the support member 10A to be tilted downward toward the uneven portion 1d. As a result, the support beam material 11 of the support member 10A can be placed on the inclined portion 3d of the rehabilitated pipe 3 along the inclined portion 3d.

The support member 10B of the inner surface 1b of the existing pipe, which is the side that protrudes relatively downward across the uneven portion 1d, is preferably positioned away from the uneven portion 1d. This allows the rehabilitated pipe 3, which has become straight and has moved away from the portion 3d that is inclined by the uneven portion 1d, to come into contact with the support member 10B.

In short, the adjacent supporting beam materials 11 of the supporting beam 9 do not necessarily need to be in contact with each other and are continuous with each other, and may be separated from each other around the uneven portion 1d. The separation distance _D11 between the adjacent supporting beam materials 11 is preferably 500 mm or less. In addition to around the uneven portion 1d, the adjacent supporting beam materials 11 may be separated from each other even in a place where the pipe diameter of the existing pipe 1 partially increases or decreases.

After lining the rehabilitating pipe 3, the backfilling material 4 is filled into the inter-pipe space 2. At this time, the rehabilitating pipe 3 is subjected to buoyancy from the backfilling material 4. In response to this, the supporting beam materials 10 of the two (plural) supporting beams 9 press down on the rehabilitating pipe 3 from above, thereby preventing the rehabilitating pipe 3 from floating up. Even in the uneven parts 1c and 1d, the rehabilitating pipe 3 can be reliably prevented from floating up by pressing the rehabilitating pipe 3 against the rehabilitating-pipe-facing surfaces 11b of the supporting beam materials 10 (10A, 10B).
As a result, the flow gradient of the rehabilitation pipe 3 can be secured.
By flattening the tip of the retractable member 30 to increase the tip area, it is possible to prevent the retractable member 30 from collapsing into or penetrating the existing pipe 1 due to the buoyancy. If the existing pipe 1 is severely deteriorated or if the buoyancy generated is large, a protective plate such as an iron plate may be interposed between the inner circumferential surface of the existing pipe 1 and the retractable member 30.

Next, another embodiment of the present invention will be described. In the following embodiment, the same reference numerals are used in the drawings to denote configurations that overlap with the above-described embodiment, and the description will be simplified.
The support beam material is not limited to flat steel plates (flat bars).
Second embodiment (FIG. 10)
As shown in Fig. 10, the support beam material 11B of the second embodiment is formed to have a cross-sectional shape in the shape of a square. The support beam material 11B includes a plurality of steel plates 15. These steel plates 15 are assembled into a rectangular ring (square), and the intersecting portions are joined by welding, bolting, or the like to form the support beam material 11B. Four steel plates 15 may be assembled into the square shape, or one or more steel plates 15 may be formed into the square shape by bending. The thickness of the steel plates 15 is preferably about 3.2 mm to 4.5 mm.

In the supporting beam material 11B, female screw holes 13A, 13B are formed in the top plate 16 and the bottom plate 17 made of the steel plate 15, respectively. The female screw holes 13A, 13B are screwed with the retractable member 30. When the retractable member 30 protrudes upward from the supporting beam material 11B, the retractable member 30 is screwed only with the female screw hole 13A of the top plate 16.
The top plate 16 and the bottom plate 17 at both ends of the support beam material 11B are formed with insertion holes 12e, 12c for passing the concrete screws 21. The insertion hole 12c in the bottom plate 17 has a larger diameter than the head 21b of the concrete screw 21. The insertion hole 12e in the top plate 16 has a larger diameter than the threaded portion of the concrete screw 21 but a smaller diameter than the head 21b. Therefore, the head 21b is engaged with the periphery of the insertion hole 12e in the top plate 16.
Preferably, the inner diameter of the insertion hole 12c is about 8 mm to 15 mm, and the inner diameter of the insertion hole 12e is about 5 mm to 7 mm.

Third embodiment (FIG. 11)
As shown in Fig. 11, the supporting beam material 11C of the third embodiment is formed to have a U-shaped cross section. The supporting beam material 11C is formed by assembling one or a plurality of steel plates 15 in a U-shape.

A female screw hole 13A is formed in a top plate 16 made of a steel plate 15 of the support beam material 11C. A retractable member 30 is screwed into the female screw hole 13A.
At both ends of the top plate 16 of the support beam material 11C, insertion holes 12e are formed to allow the concrete screws 21 to pass through and to engage the heads 21b.

<Fourth embodiment (FIG. 12)>
As shown in Fig. 12, the supporting beam material 11D of the fourth embodiment is formed to have an L-shaped cross section. The supporting beam material 11D is configured by assembling one or two steel plates 15 in an L-shape.

A female screw hole 13A is formed in a top plate 16 of the support beam material 11D, which is made of a steel plate 15. A retractable member 30 is screwed into the female screw hole 13A.
At both ends of the top plate 16 of the support beam material 11D, insertion holes 12e are formed to allow the concrete screws 21 to pass through and to engage the heads 21b.

Fifth embodiment (FIG. 13)
As shown in Fig. 13, the support beam 11E of the fifth embodiment is made of a round steel bar or a deformed steel bar and has a circular cross section. A female screw hole 13 is formed so as to penetrate the support beam 11E from top to bottom. A retractable member 30 is screwed into the female screw hole 13.
At both ends of the support beam material 11E, insertion holes 12 are formed through which concrete screws 21 can be passed and into which heads 21b can be engaged.
Preferably, a deformed steel bar having irregularities such as ribs or knots (not shown) is used as the supporting beam material 11E. This can enhance the unity with the backfill material 4.

Sixth embodiment (FIG. 14)
As shown in Fig. 14, the end of the supporting beam material 11F of the sixth embodiment is formed with uneven portions 18, 19. The uneven portions 18, 19 of adjacent supporting beam materials 11F in the supporting beam 9 are combined so as to mesh with each other in the thickness direction (up and down).

Seventh embodiment (FIG. 15)
In the seventh embodiment, the height of the support beam material 11 and the protrusion amount of the protruding member 30 are adjusted before the lining process of the rehabilitation pipe 3. More specifically, as shown in Fig. 15, a rehabilitation pipe substitute jig 40 is prepared in advance. The rehabilitation pipe substitute jig 40 is formed in a straight rod shape. The length of the rehabilitation pipe substitute jig 40 is approximately equal to the pipe diameter of the rehabilitation pipe 3 shown by the two-dot chain line in Fig. 15. Strictly speaking, the rehabilitation pipe substitute jig 40 is formed so that when its base end 41 contacts the bottom (lower half) of the existing pipe 1, its tip end 42 is positioned on the outer periphery of the upper half of the rehabilitation pipe 3.

During rehabilitation work, the support beam 11 is attached to the inner surface of the existing pipe 1 with concrete screws 21 (see Figure 6). Then, prior to lining the rehabilitated pipe 3, the base end 41 of the rehabilitation pipe substitute jig 40 is abutted against the bottom of the existing pipe 1, preferably against a position 1p that is 180° opposite the placement angle of the support beam 11. The tip 42 of the rehabilitation pipe substitute jig 40 is also directed toward the placement angle of the support beam 11. In Figure 15, the rehabilitation pipe substitute jig 40 is inclined 45° from the vertical, corresponding to the placement of the support beam 11 at an angle of ±45° from the pipe top (0°).

Furthermore, the supporting beam 11 is placed on the tip 42 of the rehabilitation pipe substitute jig 40 while being moved closer to and away from the existing pipe 1. Then, the protruding amount of the protruding members 30 is adjusted so that the supporting beam 11 directly contacts the inner peripheral surface of the existing pipe 1 or the tip of each protruding member 30 abuts against the inner peripheral surface of the existing pipe 1.
After the adjustment, the rehabilitation pipe substitute jig 40 is removed. By removing the jig, the support beam material 11 is separated from the inner peripheral surface of the existing pipe 1, and can return to a state in which it is suspended by the concrete screws 21 (see FIG. 6).
The above adjustment is performed on the support beams 11 on both the left and right sides of the pipe top using a pipe rehabilitation substitute jig 40.

Thereafter, the rehabilitating pipe 3 is lined. At this time, the supporting beams 11 are moved toward and away from the existing pipe 1, and placed on the outer circumferential surface of the rehabilitating pipe 3. Then, the supporting beams 11 naturally come into contact with the existing pipe 1, or the tips of the protruding members 30 come into contact with the existing pipe 1.
Furthermore, when the support beam material 11 is placed on the rehabilitation pipe 3, if the support beam material 11 moves away from the existing pipe 1 and the tip of the protruding member 30 moves away from the existing pipe 1, the amount of protrusion of the protruding member 30 is readjusted or fine-tuned so that the tip of the protruding member 30 abuts against the existing pipe 1.

Alternatively, when the rehabilitating pipe 3 after lining is deformed so as to be flattened by its own weight, and the supporting beam material 11 separates from the existing pipe 1 or the tip of the protruding member 30 separates from the existing pipe 1, the rehabilitating pipe 3 may be braced in the vertical direction or in the pipe diameter direction connecting the supporting beam material 11 and the part 180° opposite thereto, by using a bracing jig (not shown). In this way, the shape of the rehabilitating pipe 3 can be corrected so that the rehabilitating pipe 3 reliably hits the supporting beam material 11 and that the supporting beam material 11 or the protruding member 30 reliably hits the existing pipe 1.
As a result, the finished shape of the rehabilitating pipe 3 can be secured, and the rehabilitating pipe 3 can be reliably prevented from floating up when the backfilling material 4 is filled.

Eighth embodiment (FIG. 16)
The eighth embodiment relates to a modified embodiment of the rehabilitation pipe substitute jig. As shown in Fig. 16, the rehabilitation pipe substitute jig 50 of the eighth embodiment includes a support 51 and a receiving portion 52. The support 51 extends straight up and down. The receiving portion 52 is provided at the upper end of the support 51. The receiving portion 52 is formed in an arc shape with the same curvature as the pipe diameter of the rehabilitation pipe 3 shown by the two-dot chain line in Fig. 16. In Fig. 16, the supporting beam material 11 is disposed at an angle of ±45° from the pipe top (0°), and accordingly, the receiving portion 52 extends to an angle of ±45° from the support 51 as the center.
The length of the rehabilitating pipe substitute jig 50 (the sum of the height of the support 51 and the thickness of the receiving portion 52 ) is substantially equal to the pipe diameter of the rehabilitating pipe 3 .

In the eighth embodiment, after the supporting beams 11 are attached to the inner peripheral surface of the existing pipe 1, the lower end (base end) of the support 51 is butted against the center of the bottom of the existing pipe 1 before lining the rehabilitating pipe 3, and the rehabilitating pipe substitute jig 50 is erected vertically. As a result, the receiving part 52 is arranged to be aligned along the circumferential direction of the upper half of the outer peripheral surface of the rehabilitating pipe 3 to be lined. The supporting beams 11 are placed on both ends of the receiving part 52, and the protruding amount of the protruding member 30 is adjusted so that each supporting beam 11 directly contacts the inner peripheral surface of the existing pipe 1 or the tip of the protruding member 30 of each supporting beam 11 contacts the inner peripheral surface of the existing pipe 1. With the rehabilitating pipe substitute jig 50, the above adjustment can be performed simultaneously for the left and right supporting beams 11.
The subsequent steps are the same as those in the seventh embodiment.

Ninth embodiment (FIGS. 17 to 22)
In the ninth embodiment, in addition to the retractable member 30, an adjustment plate 60 is used as the interposition member.
The supporting beam material 11G used in this embodiment has a flat rectangular cross section, similar to the supporting beam material 11B of the second embodiment, and includes a top plate 111, a bottom plate 112, and a pair of side plates 113. As shown in FIG. 19(a), the top plate 111 is formed with a plurality of insertion holes 115, which are elongated holes extending in the longitudinal direction, at predetermined intervals in the longitudinal direction. As shown in FIG. 17, the bottom plate 112 is formed with an operation hole 116 at a position corresponding to the insertion hole 115. The operation hole 116 is large enough to include the insertion hole 115. In addition, the side plate 113 is formed with small through holes 117 at a short pitch for introducing backfilling material.

As shown in Figures 19(a) and 17, a cylindrical nut 118 is placed in the center between the insertion holes 115 of the support beam material 11G. In other words, the insertion holes 115 and nuts 118 are alternately placed along the longitudinal direction of the support beam material 11G. The upper and lower ends of this nut 118 are welded to the top plate 11 and the bottom plate 112. A retractable member 30 made of enamel set is screwed into the female threaded hole 118a of this nut 118. Before the adjustment process, the retractable member 30 is fitted into the nut 18.

As shown in Figure 20, the adjustment plate 60 has a rectangular main plate portion 61 and a rectangular sub-plate portion 62 that is narrower than the main plate portion 61 and perpendicular to the main plate portion 61, forming an L-shape. The main plate portion 61 has a slit 65 that extends in a direction perpendicular to the sub-plate portion 62 and reaches the side edge on the opposite side of the sub-plate portion 62. The width of the slit 65 is greater than the diameter of the concrete screw 21.

As in the previous embodiment, concrete screws 21 are driven into the existing pipe 1 through the insertion holes 115 of the support beam 11G, so that the support beam 11G is held in a suspended state as shown in Figures 17(a) and 18(a). In the process of lining the rehabilitated pipe 3, the support beam 11G is positioned so that it rests on the outer surface of the rehabilitated pipe 3. In this positioned state, if a gap is formed between the support beam 11G and the existing pipe 1, the protruding member 30 is screwed in so that its tip abuts against the inner circumference of the existing pipe 1 as shown in Figure 17(b).

Furthermore, in this embodiment, as shown in Fig. 17(b) and Fig. 18(b), the adjustment plate 60 is inserted as many times as necessary to fill the gap. That is, the main plate portion 61 of the first adjustment plate 60 is inserted from a direction perpendicular to the longitudinal direction of the support beam material 11G so that the slit 65 is inserted into the concrete screw 21. As a result, the main plate portion 61 is placed on the top plate 111 of the support beam material 11G, and the sub-plate portion 62 is placed against the higher side plate 113. If necessary, an additional adjustment plate 60 is inserted between the previously inserted adjustment plate 60 and the existing pipe 1 in the same manner as above. The main plate portions 61 of the adjustment plates 60 overlap, and the sub-plate portions 62 overlap each other. The inserted adjustment plate 60 is stably maintained attached to the support beam material 11G because the concrete screw 21 is inserted in the slit 65 and the sub-plate portion 62 is placed on the higher side plate 113.

As described above, the gap between the support beam material 11G and the existing pipe 1 can be filled simply by inserting the adjustment plate 60. Even if buoyancy acts on the rehabilitated pipe 3 during the filling process of the backing material 4, the adjustment plate 60, which has a larger area than the protruding member 30, can stably receive the load from the rehabilitated pipe 3 without damaging the existing pipe 1.

Although the retractable members 30 and the adjustment plates 60 can be arranged alternately, as shown in Fig. 19(b), a pair of retractable members 30 may be arranged at both ends of the support beam 30, and multiple adjustment plates 60 may be arranged between them. In this case, the function of the adjustment plates 60 can be maximized.
Only a pair of concrete screws 21 may be disposed at both ends of the supporting beam 11G. For example, in Fig. 19(c), the concrete screws 21 may be passed through insertion holes 115' formed between the protruding and retracting members 30 near both ends and both ends of the supporting beam 11G. In this case, the adjustment plate 60 may be overlapped between the protruding and retracting members 30 without being restrained by the concrete screws 21.
Furthermore, the arrangement of the retractable member 30 and the adjustment plate 60 can be changed as required.

As shown in Figure 21, adjustment plates 60 of different thicknesses may be combined. This allows the gap between the support beam material 11G and the existing pipe 1 to be filled with greater precision.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, the rod-shaped fasteners are not limited to concrete screws 21, but may be nails, anchor bolts, pins, etc. The number of rod-shaped fasteners on one support member 10 is not limited to a pair (two), but may be one or three or more. The fastening means 20 is not limited to rod-shaped fasteners, but may include hooks, etc.
A screw having a convex head, such as a hexagonal bolt, may be used as the retractable member 30. In this case, it is preferable that the height of the screw head is as low as possible.
In order to improve the unity with the backfilling material 4, holes or irregularities may be formed in the supporting beam material by punching or the like.
In places where the unevenness 1c, 1d (clearance) is too large due to partial corrosion of the existing pipe 1, the protruding members may be replaced with protruding members having a height equal to or greater than the support beam material when lining the rehabilitating pipe 3. In that case, care must be taken to ensure that the protruding members do not protrude into the rehabilitating pipe side and damage the rehabilitating pipe 3.

The present invention can be applied, for example, to the rehabilitation of aging sewer pipes.

1 Existing pipe 1c Concave uneven portion 1d Step-like uneven portion 2 Pipe space 3 Rehabilitation pipe 4 Backfilling material 5 Floating prevention device 9 Support beam 10 Support member 10A, 10B Support member 11 Support beam material 11a Existing pipe facing surface (facing surface to existing pipe)
11b Rehabilitation pipe facing surface (facing surface to the rehabilitation pipe)
11B to 11G Support beam material 12 Insertion holes 12c, 12e Insertion holes 13 Female screw hole 18 Step portion 20 Attachment means 21 Concrete screw (rod-shaped attachment body)
30 Protruding member (intervening member)
31 Screw driving operation part 40 Pipe rehabilitation substitute jig 41 Base end part 42 Tip part 50 Pipe rehabilitation substitute jig 51 Support 52 Receiving part 60 Adjustment plate (intervening member)
61 Main plate portion 62 Sub-plate portion 65 Slit

Claims (10)

A floating prevention device that prevents a rehabilitating pipe from floating up when filling a backfilling material into a pipe-to-pipe space between a rehabilitating pipe lined along the inner periphery of an existing pipe and the existing pipe,
A linear support beam material along the extension direction of the existing pipe;
An attachment means for attaching the support beam to an inner peripheral surface of an upper half of the existing pipe in a manner that allows the support beam to move toward and away from the inner peripheral surface of the upper half of the existing pipe;
Interposition members are interposed in the gap between the supporting beam material and the existing pipe with an amount of interposition adjustable according to the gap, and are arranged apart from each other in the longitudinal direction of the supporting beam material;
A floating prevention device comprising: The floating prevention device according to claim 1, characterized in that the attachment means includes a plurality of rod-shaped attachment bodies arranged at intervals in the longitudinal direction of the support beam material and attached to the existing pipe. The floating prevention device according to claim 1 or 2, characterized in that the plurality of interposition members include a plurality of protruding and retracting members that can protrude from and retract into the surface of the support beam facing the existing pipe, and the amount of protrusion of the protruding and retracting members from the facing surface is provided as the interposition amount. Each of the plurality of protruding members is formed by a screw,
4. The floating prevention device according to claim 3, wherein the supporting beam has a plurality of female screw holes into which the screws are screwed, the female screw holes being spaced apart from one another in the longitudinal direction. The floating prevention device according to claim 3 or 4, characterized in that at least one of the plurality of interposing members is constituted by an adjustment plate whose number is adjusted according to the gap, and the stacking amount of the adjustment plates is provided as the interposing amount. The floating prevention device according to any one of claims 1 to 5, characterized in that it comprises a plurality of support beams each extending along the extension direction and spaced apart from one another in the circumferential direction of the upper half of the existing pipe, and each longitudinal portion of each support beam is made of the support beam material. A method for preventing a rehabilitating pipe from floating up when filling a backfilling material into a space between an existing pipe and a rehabilitating pipe lined along an inner periphery of the existing pipe, comprising:
Prior to lining the rehabilitating pipe, a linear support beam material extending in an extension direction of the existing pipe is attached to an inner peripheral surface of an upper half of the existing pipe by an attachment means so as to be movable toward and away from the inner peripheral surface of the upper half of the existing pipe;
A method for preventing a rehabilitated pipe from floating up during existing pipe rehabilitation work, characterized in that the support beam material is moved closer to and away from the existing pipe so that it rests on the rehabilitated pipe, and the amount of interposition is adjusted so that the support beam material touches the existing pipe or so that a plurality of interposition members arranged at a distance in the longitudinal direction of the support beam material fill the gap between the support beam material and the existing pipe. The method for preventing floating described in claim 7, characterized in that the amount of interposition is adjusted when or immediately before the rehabilitation pipe is lined directly below or to the side of the support beam material. A pipe rehabilitation tool having a length substantially equal to the diameter of the pipe is prepared.
A method for preventing floating up as described in claim 7 or 8, characterized in that prior to the lining, with the base end of the rehabilitation pipe substitute jig abutted against the bottom of the existing pipe, the support beam material is placed on the tip of the rehabilitation pipe substitute jig while moving it closer to and away from the existing pipe, and the amount of interposition is adjusted so that the support beam material abuts against the existing pipe or the interposition member fills the gap between the support beam material and the existing pipe. The method for preventing floating described in any one of claims 7 to 9, characterized in that after the lining, the rehabilitated pipe is braced in the vertical direction or in the pipe diameter direction connecting the support beam material and the part 180° opposite to it.

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