Backfilling method, backfilling management device, and backfilling system for existing pipe rehabilitation

Abstract

To prevent a support from being destroyed by external force in a backfilling process of an existing pipe rehabilitation method.SOLUTION: A rehabilitation pipe 3 is installed inside an existing pipe 1 to be rehabilitated. A support 21 for restricting the floating of the rehabilitation pipe 3 is installed inside the rehabilitation pipe 3. A backfilling material 4 is injected between the rehabilitation pipe 3 and the existing pipe 1. During injection, a load applied to the support 21A is measured by a load meter 31. A safety processing unit 32 performs safety processing for suppressing an increase in the load on the basis of the load measured by the load meter 31.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a backfilling method in a construction method for rehabilitating existing pipes, such as aging sewer pipes, and in particular to a method for injecting backfill material between a rehabilitation pipe installed within the existing pipe to be rehabilitated and the existing pipe, as well as a backfilling management device and a backfilling system. [Background technology]

[0002] A known method for rehabilitating existing pipes, such as aging sewer pipes, involves installing a rehabilitating pipe inside the existing pipe and filling the backfill space between the inner periphery of the existing pipe and the outer periphery of the rehabilitating pipe with backfill material (see Patent Documents 1 and 2, etc.). When the backfill material is injected, the buoyancy of the backfill material causes the rehabilitating pipe to tend to float up. To prevent this, supports are installed inside the rehabilitating pipe.

[0003] For example, the support structure in Patent Document 1 includes rod-shaped supports arranged in a vertical and horizontal cross pattern with jack bolts. The lower ends of the vertical supports are grounded on the inner bottom surface of the rehabilitating pipe via bottom wales. The upper ends of the vertical supports are passed through through holes at the top of the rehabilitating pipe and abut against the top of the existing pipe. Both ends of the horizontal supports are abutted against the inner surface of the rehabilitating pipe via wales.

[0004] The support structure in Patent Document 2 includes an annular frame and multiple short rod-shaped supports with jack bolts. The multiple supports are arranged radially around the annular frame at intervals. Each support is abutted against the inner surface of the rehabilitating pipe via a wale. Furthermore, the support at the upper end of the annular frame is abutted against the top of the existing pipe through a through-hole at the top of the rehabilitating pipe. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 7-268853 [Patent Document 2] Japanese Patent Application Publication No. 10-121565 Summary of the Invention [Problem to be solved by the invention]

[0006] In the backfilling process of this type of existing pipe rehabilitation method, the buoyancy and pressure caused by the injection of backfill material act as external forces on the support structure via the rehabilitation pipe. If this external force exceeds the load-bearing strength of the support structure, the support structure will be destroyed, causing the rehabilitation pipe to float or its cross section to deform, even if the rehabilitation pipe is strong enough to withstand the load. In view of the above circumstances, the present invention aims to prevent the destruction of supports due to external forces during the backfilling process of the existing pipe rehabilitation method. [Means for solving the problem]

[0007] In order to solve the above problems, the backfilling method for rehabilitating existing pipes according to the present invention includes: A backfilling method for injecting backfill material between a rehabilitation pipe installed in an existing pipe to be rehabilitated and the existing pipe, a step of installing a support structure in the rehabilitation pipe to restrict the rehabilitating pipe from floating due to the injection; after said placement, initiating said injection; a step of measuring the load applied to the support during the injection using a load meter; a step of performing safety processing to suppress load increase based on the load measured by the load meter; The present invention is characterized by the following.

[0008] When the backfill material is injected, the support resists the buoyancy from the backfill material, preventing the rehabilitated pipe from floating up. Meanwhile, the buoyancy and the pressure of the backfill material act as external forces on the support through the rehabilitated pipe, applying a load to the support. This load is measured by a load meter. By monitoring the measured load, safety measures can be taken to prevent load increases, for example, when a predetermined load is reached. The predetermined load may be the withstand load of the support (equivalent to buckling load) or a value obtained by multiplying the withstand load by a safety factor. Safety measures to prevent load increases include issuing an alarm using an alarm means, stopping the injection of backfill material, and reducing the injection flow rate. This can prevent the support structure from being destroyed.

[0009] The regulation of the floating of the rehabilitated pipe is not limited to cases where the floating of the rehabilitated pipe is regulated by shoring from the start of injection of backfill material, but also includes cases where floating is allowed up to a set floating height after injection begins and floating above the set floating height is regulated. When the floating of the rehabilitating pipe is restricted from the start of injection, it is preferable that the upper end tensioning portion of the support be brought into contact with (opposed to) the top of the existing pipe in the installation step. When floating up to the set floating height is permitted, preferably, in the installation step, the upper end tensioning portion of the support is spaced downward from the top of the existing pipe by the set floating height so as to face (oppose) the top of the existing pipe. In this case, the abutment load detected when the upper end tensioning portion hits the top of the existing pipe due to the floating of the rehabilitating pipe may be set as the predetermined load, and the safety processing may be performed when the rehabilitating pipe has floated up by the set floating height.

[0010] Preferably, supports are installed at multiple positions spaced apart in the axial direction of the rehabilitated pipe, and the load applied to the support closest to the backfill material injection hole formed in the rehabilitated pipe is measured. During the injection process, the backfill material is injected through the injection hole into the backfill space between the existing pipe and the rehabilitated pipe. Because the backfill material is viscous, along the pipe axis, the closer to the injection hole in the backfill space, the earlier it is filled, and the further from the injection hole, the later it is filled. For this reason, the load applied to the support closest to the injection hole (hereinafter referred to as the "applied load") increases before the applied loads of the other supports. Therefore, by using the measured load of the support closest to the injection hole as the standard, safety treatment can be carried out for the other supports at a safer time, ensuring that destruction can be prevented in advance. Load meters may also be installed on supports far from the injection holes.

[0011] Preferably, the safety process includes issuing a warning by emitting a warning light, sounding a warning sound, or displaying a warning or load value. When the load measured by the load meter reaches a predetermined load, the alarm means is activated to emit an alarm light, sound an alarm, or display an alarm or load value. In response to the alarm, the worker can take safety measures to prevent the load from increasing, such as stopping the injection of backfill material.

[0012] If, for the above safety reasons, the valves in the backfill material injection system are all closed in one go to abruptly stop the injection of the backfill material, there is a risk that the injection pipes in the injection system will burst before or after the valves or near the injection pump. Therefore, the safety treatment preferably includes gradually reducing the injection flow rate of the backfilling material, thereby preventing the injection pipe from being damaged by a sudden change in the injection flow rate. The injection flow rate of the backfill material may be reduced stepwise over multiple times, or may be reduced continuously and steplessly. For example, the injection flow rate of the backfill material can be gradually reduced by gradually or stepwise reducing the opening of the variable throttle valve. The gradual reduction operation may be performed manually by an operator, or may be performed automatically by a controller (control means).

[0013] The safety treatment may include an operation of releasing a portion of the backfill material into a drain path. This allows the injection flow rate of the backfill material to be reduced by the amount of material that is released. After that, the injection of the backfilling material may be stopped. Since the injection flow rate of the backfilling material is temporarily reduced by the amount of the escape flow rate before the injection is stopped, the range of change in the injection amount when the injection is stopped can be reduced, and the injection pipe can be prevented from bursting.

[0014] The device of the present invention is a backfill management device that manages the injection of backfill material between an existing pipe and the rehabilitation pipe, which is carried out in a state where a rehabilitation pipe is installed inside the existing pipe to be rehabilitationd and a support structure that restricts the floating of the rehabilitation pipe is installed inside the rehabilitation pipe, and a load meter for measuring the load applied to the support during the injection; a safety processing unit that performs safety processing to suppress an increase in load based on the load measured by the load meter; The present invention is characterized by the following. When the backfill material is being injected, the load applied to the support is measured by a load meter, and based on the measured load, the safety processing unit performs safety measures to prevent the load from increasing, thereby preventing the support from being destroyed.

[0015] Preferably, supports are installed at multiple positions spaced apart in the axial direction of the rehabilitated pipe, and the load meter is installed on the support closest to the backfill material injection hole formed in the rehabilitated pipe. Because the backfill material is viscous, the load applied to the support closest to the injection hole will increase before the loads applied to the other supports. Therefore, by using the measured load of the support closest to the injection hole as the standard, it is possible to prevent the destruction of that support, as well as the destruction of the other supports.

[0016] Preferably, the load cell is provided on a vertical load-receiving support member arranged along the vertical centerline of the support. Generally, the largest load is placed on vertical load bearing supports among all supports. Therefore, by taking safety measures based on the load on vertical load bearing supports, it is possible to reliably prevent the destruction of supports.

[0017] Preferably, the load meter is interposed between the bottom of the support and the inner bottom of the rehabilitation pipe, thereby enabling the load acting on the support to be reliably detected.

[0018] Preferably, the safety processing section includes an alarm generating means having at least one of an alarm lamp, an alarm buzzer, and a display. This allows the system to warn that the load on the support has reached a predetermined level by emitting a warning light, sounding an alarm buzzer, or displaying a warning or load value on the display. In response to the warning, workers can stop the injection of backfill material or reduce the injection flow rate.

[0019] Preferably, the safety treatment section includes an injection flow rate adjustment valve provided in the backfill material injection pipe, and a valve control means for remotely operating the injection flow rate adjustment valve. This allows the injection of backfilling material to be stopped or the injection flow rate to be reduced based on the measured load through automatic control by the valve control means.

[0020] Preferably, the safety treatment section includes a drain flow rate adjustment valve provided in a drain pipe branched from the backfill material injection pipe, and a valve control means for remotely operating the drain flow rate adjustment valve. This allows the valve control means to automatically control the backfill material to escape to the drain pipe based on the measured load, thereby reducing the injection flow rate.

[0021] The system of the present invention is a backfilling system that injects backfill material between a rehabilitation pipe installed in an existing pipe to be rehabilitated and the existing pipe, an injection system having an injection pump for the backfill material and an injection pipe extending from the injection pump; a support structure that is installed in the rehabilitation pipe and that restricts the rehabilitation pipe from floating due to the injection; a load meter for measuring the load applied to the support during the injection; a safety processing unit that performs safety processing to suppress an increase in load based on the load measured by the load meter; The present invention is characterized by the following. [Effects of the Invention]

[0022] According to the present invention, it is possible to prevent the support structure from being destroyed by external forces during the backfilling process of the existing pipe rehabilitation method. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 shows a first embodiment of the present invention, and is a front cross-sectional view along line II in FIG. 2 of a support device installed in a rehabilitation pipe within an existing pipe to be rehabilitated, during the injection of backfill material. [Figure 2] FIG. 2 is a side cross-sectional view of the support device taken along line II-II in FIG. [Figure 3] FIG. 3 is an explanatory diagram of a backfilling system including the support device. [Figure 4] FIG. 4 is an explanatory diagram of a backfilling system according to a second embodiment of the present invention. [Figure 5] FIG. 5 is an explanatory diagram of a backfilling system according to a third embodiment of the present invention. [Figure 6] FIG. 6 is an explanatory diagram of a backfilling system according to a fourth embodiment of the present invention. [Figure 7] FIG. 7 is an explanatory diagram of a backfilling system according to a fifth embodiment of the present invention. [Figure 8] FIG. 8 is an explanatory diagram of a backfilling system according to a sixth embodiment of the present invention. [Figure 9] FIG. 9 shows a seventh embodiment of the present invention and is a front cross-sectional view of a support device installed in a rehabilitating pipe inside an existing pipe to be rehabilitated. [Figure 10(a)] FIG. 10(a) shows the eighth embodiment of the present invention and is a front cross-sectional view showing a support device installed in a rehabilitating pipe inside an existing pipe to be rehabilitated, in a state before a backfilling process. [Figure 10(b)] FIG. 10(b) is a front cross-sectional view showing the state in FIG. 10(a) where the upper end tensioning portion of the support device hits the top of the existing pipe due to the floating of the rehabilitating pipe caused by backfilling. [Figure 11] FIG. 11 shows a ninth embodiment of the present invention, and is a front cross-sectional view of a support device installed on a rehabilitating pipe in an existing pipe to be rehabilitated. [Figure 12] FIG. 12 is a front cross-sectional view showing a modification of the ninth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. <First embodiment (FIGS. 1 to 3)> 1 and 2 show how to rehabilitate an existing pipe 1. The existing pipe 1 to be rehabilitated is, for example, an aging sewer pipe. Note that the existing pipe to be rehabilitated is not limited to a sewer pipe, but may also be a water pipe, a gas pipe, an agricultural water pipe, a hydroelectric power generation water pipe, a tunnel, etc.

[0025] As shown in Figures 1 and 2, a rehabilitation pipe 3 (lining pipe) is installed inside an existing pipe 1. The rehabilitation pipe 3 is configured as a helical pipe made by spirally winding a long strip-shaped member 3a (profile) made of synthetic resin. Note that the rehabilitation pipe 3 is not limited to a helical pipe, and may be a synthetic resin tube, a tubular shape formed by connecting multiple annular segments in the axial direction of the pipe, or a tubular shape formed by combining multiple plate-shaped segments in the circumferential and axial directions of the pipe.

[0026] As shown in Figure 1, a backfill space 2 is defined between the inner periphery of the existing pipe 1 and the outer periphery of the rehabilitation pipe 3. A backfill material 4 is injected and filled into the backfill space 2. The backfill material 4 is a viscous fluid when injected, and hardens after injection. Mortar or cement milk is used as the backfill material 4.

[0027] As shown in Figure 3, the backfilling system 5 for injecting backfilling material comprises an injection system 10 for the backfilling material 4, a shoring device 20, and a backfilling management device 30. The injection system 10 has an injection pump 11 and an injection pipe 12 for the backfilling material 4. The injection pump 11 is mounted on, for example, a work vehicle 6 shown in a simplified form in the figure. An injection pipe 12, such as a resin hose, extends from the injection pump 11 and is installed inside the manhole 7 and the rehabilitation pipe 3. The injection pipe 12 is provided with, for example, a manually operated on-off valve 13.

[0028] 2, an injection hole 3d is formed, for example, near the top of the rehabilitating pipe 3. The tip of the injection pipe 12 is connected to the injection hole 3d and faces the backfill space 2.

[0029] As shown in Figures 1 and 2, a shoring device 20 is installed inside the rehabilitating pipe 3 to restrict floating and cross-sectional deformation of the rehabilitating pipe 3 when backfill material is injected. The shoring device 20 includes a plurality of shoring structures 21 and a waling 22. As shown in Figure 2, the plurality of shoring structures 21 are arranged at intervals in the axial direction of the rehabilitating pipe 3. In other words, the shoring structures 21 are installed at a plurality of positions spaced apart in the axial direction of the rehabilitating pipe 3.

[0030] As shown in Figure 1, the support structure 21 includes vertical and horizontal rod-shaped supports 23, 24 arranged in a cross shape. Each support structure 23, 24 includes a jack bolt 25 and is extendable. The vertical load-receiving support structure 23 is arranged vertically along the vertical center line Lc of the support structure 21. The bottom 23b (lower end) of the vertical load-receiving support structure 23 is grounded to the inner bottom 3b of the rehabilitation pipe 3 via a bottom wale 22B. The upper end bracing portion 23p of the vertical load-receiving support structure 23 is abutted against the top of the existing pipe 1 through a through-hole 3c at the top of the rehabilitation pipe 3.

[0031] As shown in Fig. 1, a horizontal support 24 intersects the vertical load-bearing support 23 at its midpoint. Both ends of the support 24 are abutted against the inner side of the side of the rehabilitation pipe 3 via wale protrusions 22. As shown in Fig. 2, each wale protrusion 22 extends in the pipe axial direction (left-right direction in the figure).

[0032] As shown in Figure 3, the backfill management device 30 manages the injection of backfill material 4 into the backfill space 2, and includes a load meter 31 and a safety processing unit 32. The load meter 31 outputs a detection signal according to the input load. For example, a small, sealed load cell is used as the load meter 31. Note that the load meter 31 is not limited to a load cell, and may be an analog load meter.

[0033] 2, the load meter 31 is preferably provided on the support 21A (first support) that is closest to the injection hole 31d among the multiple supports 21. For example, the load meter 31 is provided on the bottom 23b of the vertical load-receiving support 23 in the support 21A. More specifically, the load meter 31 is interposed between the bottom 23b of the vertical load-receiving support 23 and the bottom wale 22B, and further between the bottom 23b of the support 21A and the inner bottom 3b of the rehabilitation pipe 3. In this way, the load meter 31 measures the load applied to the vertical load-receiving support 23 of the support 21A. In addition, the load meter 31 may also be provided on supports 21 other than the support 21A.

[0034] 3, the safety processing unit 32 performs safety processing to suppress an increase in the load on the support 21 based on the load measured by the load meter 31, and includes a controller 33 (alarm control means) and an alarm means 40. The controller 33 includes an input unit 34, a CPU 35, a memory unit 36, an alarm drive circuit 37, etc. A detection signal line 31c from the load meter 31 is connected to the input unit 34. The input unit 34 converts the electric signal from the load meter 31 into a signal for the controller 33. A control program for safety processing is executed by the CPU 35.

[0035] The memory unit 36 stores the control program and data such as the threshold value Ps for safety processing. The threshold value Ps is preferably a load value that takes into account a safety factor for the withstand load of the shoring 21. More preferably, the threshold value Ps is a load value that takes into account a safety factor for the withstand load (buckling load) of the vertical load-receiving support 23. The safety factor is preferably 1.2 or 1.5 or more, and more preferably approximately 2.0. Therefore, the threshold value Ps is preferably a value obtained by multiplying the calculated withstand load (buckling load) by the reciprocal of the safety factor (preferably approximately 50%). Furthermore, taking into account the time lag between the load reaching the threshold value and the execution of safety processing, as well as variations in the distance from the injection hole 3d to the shoring 21A, the threshold value Ps may be set to, for example, approximately 90% of the load value that takes into account a safety factor for the withstand load (buckling load). Note that, in cases where injection needs to be stopped instantly, the threshold value Ps may be set to the withstand load of the shoring 21 without taking into account a safety factor. The memory unit 36 may include a data logger that stores the load measured by the load meter 31 .

[0036] An alarm means 40 is connected to the alarm drive circuit 37 of the controller 33 . The alarm emitting means 40 is operated by automatic control of the controller 33 based on the measured load of the load meter 31. The alarm emitting means 40 has at least one of an alarm lamp 41, an alarm buzzer 42, and an indicator display 43. It may have only one, two, or all three of these three. The alarm lamp 41 emits an alarm light. An example of the alarm lamp 41 is a rotating alarm light. The warning buzzer 42 outputs a warning sound.

[0037] The display 43 displays an alarm or a load value. The alarm display includes characters, symbols, illustrations, etc., indicating that the load applied to the support 21 has reached a predetermined magnitude (for example, threshold value Ps). The load value display is a display (raw data) of the load measurement value from the load meter 31, and may be a numerical display, a graphical display such as a bar graph, or a graphic display. Preferably, the load value display is always displayed in real time, regardless of whether the load has reached threshold value Ps or not.

[0038] The backfilling process in the rehabilitation method for the existing pipe 1 is carried out as follows. After the rehabilitation pipe 3 is installed inside the existing pipe 1, the support device 20 is installed inside the rehabilitation pipe 3. At this time, the upper end tensioning portion 23p of the vertical load-receiving support member 23 is passed through the through hole 3c at the top of the rehabilitation pipe 3 and brought into contact with (faces) the top of the existing pipe 1. Also, an injection hole 3d is formed in the rehabilitation pipe 3, and the tip of the injection pipe 12 is connected to the injection hole 3d. A load meter 31 is installed on the support 21A closest to the injection hole 3d. Thereafter, the injection pump 11 is driven, the on-off valve 13 is opened, and the injection of the backfilling material 4 is started. The backfilling material 11 is injected from the injection pump 11 through the injection pipe 12 into the backfilling space 2.

[0039] When the backfill material 4 is injected, the rehabilitating pipe 3 is subjected to buoyancy and pressure from the backfill material 4 in the backfill space 2. Furthermore, the buoyancy and pressure act as an external force on the shoring device 20 via the rehabilitating pipe 3. This external force (load) is received by the shoring device 20. This makes it possible to prevent the rehabilitating pipe 3 from floating up or its cross-sectional deformation. In particular, the shoring 21 can prevent the rehabilitating pipe 3 from floating up. The vertical load is mainly received by the vertical load-receiving shoring material 23 of the shoring 21.

[0040] Because the backfill material 4 is viscous during injection, it is filled first in the backfill space 2 in the direction of the pipe axis toward the injection hole 3d, and is filled later in the backfill space 2 farther from the injection hole 3d. In other words, as shown in Figure 2, the liquid level 4L of the backfill material 4 in the backfill space 2 during injection is higher the closer it is to the injection hole 3d and becomes lower the farther it is from the injection hole 3d. For this reason, the load on the support 21A closest to the injection hole 3d becomes large before the loads on the other supports 21 become large.

[0041] The load on the support 21A is measured by a load meter 31. In particular, the vertical load on the support 21A is measured. The measured load information is input to a controller 33 of a safety processing unit 32. In the controller 33, a CPU 35 determines whether or not the measured load has reached a threshold value Ps (predetermined load).

[0042] When it is determined that the measured load has reached the threshold value Ps, a control signal is output from the CPU 35 to an alarm driving circuit 37. In response to the control signal, a drive signal is output from the alarm driving circuit 37 to an alarm means 40. The drive signal activates the alarm means 40, thereby carrying out safety processing. More specifically, an alarm lamp 41 emits an alarm light. Alternatively, an alarm buzzer 42 outputs an alarm sound. Alternatively, an alarm display or load value display is shown on the display 43.

[0043] This allows the worker to recognize that the load on the support 21 has reached a predetermined level, and to take the necessary action to prevent the load from increasing, such as stopping the injection of the backfill material 4. For example, the injection of the backfilling material 4 can be stopped by the worker manually closing the on-off valve 13 or stopping the injection pump 11. As a result, it is possible to prevent the load on the support 21 from increasing any further, and to prevent the support 21 from being destroyed. In particular, it is possible to prevent the vertical load-receiving support 23 from buckling due to an excessive load.

[0044] Furthermore, since the load on the support 21A closest to the injection hole 3d increases before the load on the other supports 21, by using the measured load on that support 21A as the standard, safety treatment can be carried out for the other supports 21 at a safer time, thereby reliably preventing destruction in advance. The backfilling material 4 at a high level near the injection hole 3d in the backfilling space 2 flows to the lower level side in the pipe axis direction after injection is stopped, thereby reducing the load applied to the support 21A. The alarm issuing means 40 may be configured to stop issuing an alarm manually by an operator or automatically by the controller 32.

[0045] After safety processing is performed, the backfill material 4 that has been injected into the backfill space 2 is allowed to harden to a certain extent for a while (for example, 12 hours to the next day). As the backfill material 4 hardens, its buoyancy weakens, and preferably disappears. After that, injection of the backfill material 4 is resumed. Prior to resuming, it is preferable to slightly loosen the jack bolts 25 of the shoring 21 to remove the excess pressing force caused by the decrease in buoyancy. Then, the backfill material 4 is injected until it is filled into the backfill space 2. At this time, the backfill management device 30 monitors the load applied to the shoring 21, and when the predetermined load Ps is reached, safety processing is performed.

[0046] Next, another embodiment of the present invention will be described. In the following embodiment, the same components as those already described will be denoted by the same reference numerals in the drawings and the description thereof will be omitted. <Second embodiment (Fig. 4)> As shown in Figure 4, in the backfilling system 5B of the second embodiment of the present invention, a variable throttle valve 14 (injection flow rate adjustment valve) is provided in place of the on-off valve 13 (Figure 3) in the injection pipe 12. An operator can adjust the injection flow rate of the backfilling material 4 by manually adjusting the opening of the variable throttle valve 14. During normal operation, the variable throttle valve 14 is fully open.

[0047] During the injection process of the backfill material 4, when the load measured by the load meter 31 reaches a predetermined magnitude Ps and the alarm means 40 is activated, the operator closes the variable throttle valve 14. Preferably, the valve is closed gradually over a period of 5 to 30 seconds. By gradually reducing the injection flow rate rather than suddenly setting it to zero, it is possible to prevent the injection pipe 12 from bursting due to a sudden change in the injection flow rate. Incidentally, if the injection flow rate of the backfilling material 4 is suddenly reduced to 0, the injection pipe 12 may burst before or after the on-off valve 13 (FIG. 3) or near the injection pump 11. By reducing the injection flow rate of the backfilling material 4 and eventually reaching zero, the increase in the load applied to the support 21 can be suppressed, and the destruction of the support 21 can be prevented.

[0048] <Third embodiment (Fig. 5)> As shown in Fig. 5, in a backfilling system 5C according to a third embodiment of the present invention, a drain pipe 15 (drain path) branches off from the injection pipe 12. A drain flow rate adjustment valve 16 is provided in the drain pipe 15. The drain flow rate adjustment valve 16 is configured as a manual on-off valve or a variable throttle valve. Under normal conditions, the drain adjustment valve 16 is fully closed.

[0049] As shown by the two-dot chain line in Figure 5, an on-off valve 13 may be provided in the injection pipe 12 downstream of the branching portion of the drain pipe 15. Instead of the on-off valve 13, a variable throttle valve 14 (Figure 4) may be provided.

[0050] During the injection process of the backfill material 4, when the load measured by the load meter 31 reaches a predetermined magnitude Ps and the alarm means 40 is activated, the worker opens the drain flow control valve 16. This may be done gradually over time. This allows some of the backfill material 4 to escape into the drain pipe 15 (drain path), reducing the injection flow rate into the backfill space 2 and preventing the destruction of the support 21.

[0051] Thereafter, the on-off valve 13 may be closed to stop the injection. In this case, the injection flow rate of the backfilling material 4 is temporarily reduced by the amount of the escape flow rate to the drain pipe 15 before the injection is stopped, so that the range of change in the injection amount when the injection is stopped can be reduced and the injection pipe 12 can be prevented from bursting.

[0052] <Fourth embodiment (FIG. 6)> As shown in Figure 6, in a backfilling system 5D according to a fourth embodiment of the present invention, a remotely controlled on-off valve 13A is provided in the injection pipe 12 of the injection system 10 instead of the manual on-off valve 13. The on-off valve 13A is opened and closed by remote control. The drive system of the on-off valve 13A may be electromagnetic or electric. During normal operation, the on-off valve 13A is in an open state.

[0053] The opening and closing of the on-off valve 13A is automatically controlled by a controller 33A (valve control means). The controller 33A is provided with a valve drive circuit 38 instead of the alarm drive circuit 37 (FIGS. 3 to 5). The valve drive circuit 38 is connected to the on-off valve 13A via a control signal line 38c. The on-off valve 13A and the controller 33A constitute a safety process part 32.

[0054] The safety processing part 32 of the fourth embodiment does not include the alarm emitting means 40 (FIGS. 3 to 5). Note that the fourth embodiment may also include the alarm emitting means 40, and the controller 33A may control the alarm emitting means 40 in addition to the on-off valve 13A.

[0055] When the backfilling material 4 is injected, the measured load information from the load meter 31 is input to the controller 33A. In the controller 33A, the CPU 35 determines whether or not the measured load has reached a predetermined magnitude Ps. If it is determined that the measured load has reached the predetermined magnitude Ps, the CPU 35 outputs a control signal for the on-off valve 13A to the valve drive circuit 38. Based on this control signal, the valve drive circuit 38 outputs a drive signal to the on-off valve 13A. The drive signal closes the on-off valve 13A. This automatically stops the injection of the backfilling material 4 by remote control. As a result, the support 21 can be prevented from being destroyed by an excessive load.

[0056] <Fifth embodiment (FIG. 7)> As shown in Figure 7, in a backfilling system 5E according to a fifth embodiment of the present invention, a remotely controlled variable throttle valve 14A (injection flow rate adjusting valve) is provided in place of the on-off valve 13A (Figure 6) in the injection pipe 12 of the injection system 10. The opening of the variable throttle valve 14A is adjusted continuously or in stages by remote control. The drive system of the variable throttle valve 14A may be electromagnetic or electric. During normal operation, the variable throttle valve 14A is fully open.

[0057] The opening degree of the variable throttle valve 14A is automatically controlled by a controller 33A (valve control means). A valve drive circuit 38 of the controller 33A is connected to the variable throttle valve 14A via a control signal line 38c. The variable throttle valve 14A and the controller 33A constitute a safety processing unit 32.

[0058] Although the safety processing unit 32 of the fifth embodiment does not include the alarm means 40 (Figures 3 to 5), the fifth embodiment may also include the alarm means 40, and the controller 33A may also control the alarm means 40 in addition to the variable throttle valve 14A.

[0059] During the injection process of the backfilling material 4, measured load information from the load meter 31 is input to the controller 33A. In the controller 33A, the CPU 35 determines whether the measured load has reached a predetermined magnitude Ps. When it is determined that the measured load has reached the predetermined magnitude Ps, the CPU 35 outputs a control signal for the variable throttle valve 14A to the valve drive circuit 38. Based on this control signal, the valve drive circuit 38 outputs a drive signal to the variable throttle valve 14A. The drive signal drives the variable throttle valve 14A in the closing direction. This automatically reduces the injection flow rate of the backfilling material 4. Preferably, injection is eventually stopped. As a result, it is possible to prevent the support 21 from being destroyed by an excessive load.

[0060] More preferably, the opening of variable throttle valve 14A is gradually reduced over a period of 5 to 30 seconds under the control of controller 33A. The opening may be reduced continuously without any steps, or may be reduced in multiple steps. Therefore, the injection flow rate is gradually reduced over time rather than reaching zero in one step. This prevents injection tube 12 from bursting due to a sudden change in the injection flow rate.

[0061] It is not necessary to start reducing the opening of the variable throttle valve 14A only after the measured load reaches a predetermined load Ps, which is the load-bearing capacity (buckling load) of the support 21 multiplied by a safety factor; the opening of the variable throttle valve 14A may also start to be reduced in accordance with the increase in the measured load before the measured load reaches the predetermined load Ps. The final opening of the variable throttle valve 14A after the gradual reduction is not limited to being fully closed, but may be in a slightly open state.

[0062] <Sixth embodiment (FIG. 8)> As shown in Figure 8, in a backfilling system 5F according to a sixth embodiment of the present invention, a drain pipe 15 branches off from the injection pipe 12 of the injection system 10, and a remotely controlled drain flow rate adjustment valve 16A is provided in the drain pipe 15. The drain flow rate adjustment valve 16A may be an on-off valve that is opened and closed by remote control, or may be a variable throttle valve whose opening is adjusted continuously or in stages by remote control. The drive system of the drain flow rate adjustment valve 16A may be electromagnetic or electric. Under normal conditions, the drain flow rate adjustment valve 16A is fully closed.

[0063] Drain flow rate adjustment valve 16A is automatically controlled by a controller 33A (valve control means). A valve drive circuit 38 of controller 33A is connected to drain flow rate adjustment valve 16A via a control signal line 38d. Drain flow rate adjustment valve 16A and controller 33A constitute a safety processing unit 32.

[0064] Although the safety processing unit 32 of the sixth embodiment does not include the alarm means 40 (Figures 3 to 5), the sixth embodiment may also include the alarm means 40, and the controller 33A may also control the alarm means 40 in addition to the drain flow rate adjustment valve 16A.

[0065] When the backfill material 4 is injected, the measured load information from the load meter 31 is input to the controller 33A. In the controller 33A, the CPU 35 determines whether the measured load has reached a predetermined magnitude Ps. If it is determined that the measured load has reached the predetermined magnitude Ps, the CPU 35 outputs a control signal for the drain flow rate adjustment valve 16A to the valve drive circuit 38. Based on the control signal, the valve drive circuit 38 outputs a drive signal to the drain flow rate adjustment valve 16A. The drive signal opens the drain flow rate adjustment valve 16A. The valve 16A may be opened gradually over time. This allows a portion of the backfill material 4 to escape into the drain pipe 15, reducing the injection flow rate into the backfill space 2. As a result, destruction of the support 21 can be prevented.

[0066] 8, in the sixth embodiment, a remotely controlled on-off valve 13A may be provided in the injection pipe 12 downstream of the branch point of the drain pipe 15. After the drain flow rate adjustment valve 16A is opened, the on-off valve 13A may be closed by remote control from the controller 33A, thereby stopping the injection of the backfilling material 4. In this case, the injection flow rate of the backfilling material 4 is temporarily reduced by the amount of the escape flow rate to the drain pipe 15 before the injection is stopped, so that the range of change in the injection amount when the injection is stopped can be reduced and the injection pipe 12 can be prevented from bursting.

[0067] In place of the remotely controlled on-off valve 13A, a remotely controlled variable throttle valve 14A may be provided in the injection pipe 12 downstream of the branching portion of the drain pipe 15. Furthermore, instead of the remotely controlled on-off valve 13A, a manual on-off valve 13 or a manual variable throttle valve 14 may be provided. In response to the issuance of a warning by the warning means 40, an operator may close the on-off valve 13 or the variable throttle valve 14.

[0068] The location where the load meter 31 is installed in the support 21 is not limited to the bottom 23b of the vertical load-receiving support 23 (FIG. 1). Seventh embodiment (FIG. 9) 9, in the seventh embodiment of the present invention, a load meter 31 is provided in the middle of the vertical load-receiving support 23. The vertical load-receiving support 23 is divided into two support members 26 and 27 in the longitudinal direction. The load meter 31 is interposed between these support members 26 and 27.

[0069] The support 21 does not necessarily have to prevent the rehabilitating pipe 3 from floating up from the very beginning of the backfill material 4 injection process. Eighth embodiment (FIG. 10) As shown in Figure 10(a), in the eighth embodiment of the present invention, at the time of installation of the support device 20, i.e., before the start of injection of the backfill material 4, the upper end tensioning portion 23p of the support 21 is facing (opposite) the top 1p of the existing pipe 1, while being spaced downward from the top 1p of the existing pipe 1 by the set floating height H.

[0070] The backfill material 4 is then injected. At this time, the rehabilitating pipe 3 floats up due to the buoyancy of the backfill material 4. As shown in Figure 10(b), when the rehabilitating pipe 3 floats up by the set floating height H, the upper end bracing portion 23p abuts against the top 1p of the existing pipe 1. This prevents the rehabilitating pipe 3 from floating any further. In addition, a contact load is applied to the vertical load-bearing support 23, and this contact load is measured by the load meter 31. This makes it possible to detect that the upper end bracing portion 23p has abutted against the top 1p of the existing pipe. At this point, safety measures may be taken to prevent an increase in load, such as temporarily halting the injection of the backfill material 4. After that, it may be possible to wait until the injected backfill material 4 hardens and loses its buoyancy, and then resume injection of the backfill material 4.

[0071] Although detailed illustrations are omitted, according to the eighth embodiment, the set floating heights H of multiple supports 21 spaced apart in the pipe axis direction (the direction perpendicular to the plane of the paper in Figure 10(a)) are made different from each other depending on the position of each support 21 in the pipe axis direction, so that a predetermined gradient can be given to the rehabilitated pipe 3 after floating by injecting backfill material 4.

[0072] The support of the support device is not limited to a cross-shaped structure. <Ninth embodiment (FIG. 11)> As shown in FIG. 11 , in a shoring device 50 according to a ninth embodiment of the present invention, a shoring 51 is formed in a generally annular shape. The shoring 51 includes an annular frame 52 and a plurality of shoring members 53. Each shoring member 53 has a jack bolt 25 and is formed in a short rod shape. The plurality of shoring members 53 are arranged radially at intervals around the circumferential direction of the annular frame 52. Each of the shoring members 53, except for the upper shoring member 53A, is abutted against the inner surface of the rehabilitation pipe 3 via a wale 22. The shoring member 53A (upper end bracing portion) is passed through a through hole 3c at the top of the rehabilitation pipe 3 and abuts against the top of the existing pipe 1. The upper shoring member 53A and the lower shoring member 53B constitute vertical load-bearing shoring members that extend along the vertical center line Lc of the shoring 51.

[0073] A load meter 31 is attached to the upper support 53A. This allows the vertical load acting on the support 51 to be measured. When the backfill material 4 is injected, safety measures can be taken to prevent an increase in load based on the measurement information from the load meter 31.

[0074] <Modification of the ninth embodiment (FIG. 12)> In the shoring device 50, the load meter 31 does not necessarily have to be provided on the upper end shoring material 53A. As shown in Fig. 12, the load meter 31 may be provided on the lower end shoring material 53B.

[0075] Furthermore, the location of the load meter 31 is not limited to the supports 53A and 53B on the vertical center line Lc of the support 51. As shown by the two-dot chain line in Fig. 12, the load meter 31 may be provided on any one of a plurality of (four in this case) diagonal supports 53C. The load acting on the diagonal support 53C may be converted into a vertical load using the angle of the support 53C or the like to determine whether or not safety measures can be taken, or the measured load acting on the support 53C itself may be used as a reference to determine whether or not safety measures can be taken. Alternatively, a plurality of load cells 31 may be provided on different supports 53, and the measured values of these load cells 31 may be combined to determine whether or not safety measures can be taken.

[0076] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention. For example, the support may be a single rod shape including the vertical load-bearing support 23 but not including the horizontal support 24 . In cases where the construction span is short, the number of supports in the support device may be only one. Before the measured load reaches the withstand load (equivalent to buckling load) of the support or a value obtained by multiplying that by a safety factor, safety measures such as a gradual reduction in the injection flow rate may be implemented. The reduction rate of the injection flow rate may be adjusted according to the measured load. As the measured load increases, the injection flow rate may be reduced continuously or in stages.

[0077] Multiple injection holes 3d may be provided at intervals in the axial direction of the rehabilitating pipe 3. In this case, safety measures may be taken for each injection hole 3d. For example, a load meter 31 may be provided on the support 21 nearest each injection hole 3d, and when the measured load for each load meter 31 reaches a predetermined magnitude Ps, the injection of backfill material from the injection hole 3d nearest that load meter 31 may be stopped or the injection flow rate may be gradually reduced. Alternatively, when the measured load of at least one of the multiple load meters 31 reaches a predetermined magnitude Ps, the injection of backfill material from the multiple injection holes 3d may be stopped or the injection flow rate may be gradually reduced. [Industrial Applicability]

[0078] The present invention can be applied to, for example, the rehabilitation of deteriorated sewer pipes. [Explanation of symbols]

[0079] 1 Existing pipes 2 Backfill space 3 Rehabilitation pipe 3b Inner bottom 3c through hole 3d injection hole 4 Backfill material 5 Backfilling System 5B, 5C, 5D, 5E, 5F Backfilling System 10 Injection system 11 Infusion pump 12 Injection tube 13 Manual on-off valve 13A Remotely controlled on-off valve 14 Manual variable throttle valve (injection flow rate adjustment valve) 14A Remotely controlled variable throttle valve (injection flow rate adjustment valve) 15 Drain pipe (drain line) 16 Manual drain flow control valve 16A Remotely controlled drain flow control valve 20 Shoring equipment 21 Shoring 21A Shoring closest to injection hole (shoring 1) 23 Vertical load support 23b bottom 23p Upper end bracing part 30 Backfill management device 31 Load cell 32 Safety Processing Department 33 Controller (alarm control means) 33A Controller (valve control means) 40 Means of notification 41 Warning lamp 42 Alarm buzzer 43 Display 50 Shoring equipment 51 Shoring 53A Upper support (upper tension part, vertical load support) 53B Lower end support (vertical load support) 53C Diagonal support H Set floating height Lc Vertical center line of support

Claims

1. A backfilling method for injecting backfill material between a rehabilitation pipe installed in an existing pipe to be rehabilitated and the existing pipe, a step of installing a support structure in the rehabilitation pipe to restrict the rehabilitating pipe from floating due to the injection; after said placement, initiating said injection; a step of measuring the load applied to the support during the injection using a load meter; a step of performing safety processing to suppress load increase based on the load measured by the load meter; A backfilling method for rehabilitating existing pipes, comprising:

2. A backfilling method as described in claim 1, in which supports are installed at multiple positions spaced apart in the axial direction of the rehabilitation pipe, and the load applied to the support closest to the backfill material injection hole formed in the rehabilitation pipe is measured.

3. The backfilling method according to claim 1 or 2, wherein the safety processing includes issuing an alarm by emitting an alarm light, sounding an alarm, displaying an alarm, or displaying a load value.

4. 3. The backfilling method according to claim 1, wherein the safety treatment includes gradually reducing the injection flow rate of the backfilling material.

5. 3. The backfilling method according to claim 1, wherein the safety treatment includes an operation of releasing a portion of the backfilling material into a drainage path.

6. A backfill management device that manages the injection of backfill material between an existing pipe and the rehabilitation pipe, which is carried out in a state where a rehabilitation pipe is installed in an existing pipe to be rehabilitationd and a support that restricts the floating of the rehabilitation pipe is installed in the rehabilitation pipe, a load meter for measuring the load applied to the support during the injection; a safety processing unit that performs safety processing to suppress an increase in load based on the load measured by the load meter; A backfill management device comprising:

7. Support structures are installed at multiple positions apart in the pipe axis direction of the rehabilitation pipe, The backfill management device according to claim 6, wherein the load meter is provided on the support closest to the backfill material injection hole formed in the rehabilitation pipe.

8. 7. A backfill management device according to claim 6, wherein the load meter is provided on a vertical load-receiving support arranged along the vertical center line of the support.

9. A backfill management device as described in claim 6, wherein the load meter is interposed between the bottom of the support and the inner bottom of the rehabilitation pipe.

10. A backfill management device according to any one of claims 6 to 9, wherein the safety processing part includes an alarm means having at least one of an alarm lamp, an alarm buzzer, and a display.

11. The backfill management device according to any one of claims 6 to 9, wherein the safety processing unit includes an injection flow rate adjustment valve provided in the backfill material injection pipe and a valve control means for remotely operating the injection flow rate adjustment valve.

12. A backfill management device as described in any one of claims 6 to 9, wherein the safety treatment unit includes a drain flow control valve provided in a drain pipe branched from the backfill material injection pipe, and a valve control means for remotely operating the drain flow control valve.

13. A backfilling system that injects backfill material between a rehabilitation pipe installed in an existing pipe to be rehabilitated and the existing pipe, an injection system having an injection pump for the backfill material and an injection pipe extending from the injection pump; a support structure that is installed in the rehabilitation pipe and that restricts the rehabilitation pipe from floating due to the injection; a load meter for measuring the load applied to the support during the injection; a safety processing unit that performs safety processing to suppress an increase in load based on the load measured by the load meter; A backfilling system comprising:

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