Water-stopping plug, grout hole water-stopping device, and grout hole water-stopping method

Abstract

To propose a water stop plug, a grout hole water stop device, and a grout hole water stop method that can maintain water stop properties without being moved by water pressure even under high water pressure.SOLUTION: A water stop plug 40 comprising a water stop member 41 that expands laterally due to pressure from the front and back, a pressing member 42 attached to a front surface of the water stop member 41, a holding member 43 attached to a rear surface of the water stop member 41, and a moving mechanism 44 that moves the pressing member 42 forward and backward relative to the holding member 43 is installed in a grout hole 11 of a segment 1 to stop water. The holding member 43 is provided with a locking portion 45 that can lock onto a thread of a female thread 13 of the grout hole 11, thereby preventing it from coming off.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a water stop plug used for a grout hole of a segment, a grout hole water stop device, and a grout hole water stop method.

Background Art

[0002] In the shield method, a lining is formed by continuously arranging segment rings formed by combining a plurality of segments in the excavation direction. The cutting of the ground by the shield tunneling machine is performed in a form including an over-excavated portion so as to have a cross-section larger than that of the shield tunneling machine and the segment ring. It is necessary to fill the gap (the back surface of the segment) between the lining formed by over-excavation and the ground with a backfill material to suppress the collapse of the ground and the like. The injection of the backfill material to the back surface of the segment is performed from a grout hole formed in the segment. In addition, when performing ground improvement or soil investigation around the tunnel, if a grout hole is used, there is no need to form a new through hole in the tunnel lining. When performing ground improvement or soil investigation from the grout hole, it is necessary to stop the water in the grout hole until the equipment used for ground improvement or soil investigation is removed and a cap is installed on the grout hole. For water stop of the grout hole, a water stop plug inserted into the grout hole may be used. For example, the water stop plug of Patent Document 1 includes a rubber hollow bag, and expands with compressed air injected into the hollow bag to perform water stop by adhering to the inner surface of the grout hole. However, since the above water stop plug is fixed only by the frictional force with the inner surface of the grout hole, there is a risk of being pushed back from the grout hole to the inside of the tunnel by the water pressure under high water pressure.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] The present invention aims to propose a water-sealing plug, a grout hole water-sealing device, and a grout hole water-sealing method that can maintain water-sealing properties without being moved by water pressure, even under high water pressure. [Means for solving the problem]

[0005] To solve the aforementioned problems, the water-stopping plug of the present invention is installed in a grout hole of a segment and comprises a water-stopping member that expands laterally (radially in the grout hole) by pressure acting from the front and rear (axial direction of the grout hole), a pressing member attached to the front surface of the water-stopping member, a retaining member attached to the rear surface of the water-stopping member, and a moving mechanism that moves the pressing member forward and backward relative to the retaining member. In the expanded state of the water-stopping member, in order to restrict the axial movement of the water-stopping plug, A locking portion may be formed in the grout hole that can engage with the threads of the female screw. In the expanded state of the water-stopping member, in order to restrict the axial movement of the water-stopping plug, A locking member having a locking portion that can engage with the threads of the female screw of the grout hole may be attached to the retaining member. Furthermore, the grout hole water-stopping device of the present invention comprises a valve attached to the grout hole of a segment, a prepender connected to the valve, a rod inserted through the prepender and the valve, and the water-stopping plug to which the moving mechanism is attached at the tip of the rod. Furthermore, the grout hole sealing method of the present invention seals a grout hole in a segment using a sealing plug, and comprises a valve installation step of attaching a valve and a prepender to the grout hole of the segment, a plug insertion step of inserting the sealing plug attached to the tip of a rod into the grout hole through the prepender and valve, and a plug expansion step of expanding the sealing member. In the plug insertion step, the locking portion is locked to the threads of the grout hole. In the plug expansion step, the moving mechanism is operated using the rod to apply pressure from the front and rear to the sealing member, thereby expanding the sealing member and sealing the grout hole.

[0006] According to this water-stopping plug, grout hole water-stopping device, and grout hole water-stopping method, the water-stopping member expands in diameter, allowing it to adhere tightly to the inner surface of the grout hole and ensure high water-stopping performance. Furthermore, since the locking portion is locked into the threads (spiral grooves) of the grout hole, the water-stopping plug will not be pushed back (come out of the grout hole) even under high water pressure. Furthermore, if the moving mechanism includes a bolt whose tip is fixed to the pressing member and a nut screwed onto the bolt on the rear surface of the pressing member, then by rotating the nut, a pressing force can be applied to the water-stopping member, thereby expanding its diameter. [Effects of the Invention]

[0007] According to the present invention, the water-stopping plug, grout hole water-stopping device, and grout hole water-stopping method make it possible to maintain water-stopping properties even under high water pressure. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-sectional view showing an overview of the soil investigation conducted from inside the shield tunnel. [Figure 2] This diagram shows a grout hole, where (a) is a cross-sectional view and (b) is a view taken along arrow A in (a). [Figure 3] This is a cross-sectional view showing a check valve recovery device. [Figure 4] This diagram shows a check valve removal tool, where (a) is a side view and (b) is a cross-sectional view. [Figure 5] This diagram shows a check valve removal tool, where (a) is a view from arrow B in Figure 4, and (b) is a view from arrow C in Figure 4. [Figure 6] This is a cross-sectional view showing a grout hole sealing device. [Figure 7] These are diagrams showing a water-stopping plug, where (a) is a view from arrow D in Figure 6, (b) is a view from arrow E in Figure 6, and (c) is a view from arrow F in Figure 6. [Figure 8] This is an enlarged cross-sectional view showing the locking mechanism. [Figure 9] This is a flowchart showing the procedure for the soil investigation method of this embodiment. [Figure 10] This is a cross-sectional view showing the cap removal process. [Figure 11] This is a cross-sectional view showing the equipment installation process. [Figure 12] This is a cross-sectional view showing the process of removing a check valve, where (a) is when the check valve removal jig is installed, (b) is when the check valve is being cut, (c) is when the cutting of the check valve is finished, and (d) is when the check valve removal jig is being retrieved. [Figure 13] This is a cross-sectional view showing the work status of the sample collection process. [Figure 14] This is a cross-sectional view showing the temporary water-stopping process, where (a) is when the water-stopping plug is inserted and (b) is when the water-stopping plug is expanded. [Figure 15] This is a cross-sectional view showing the equipment removal process. [Figure 16] This is a cross-sectional view showing the cap restoration process. [Modes for carrying out the invention]

[0009] In this embodiment, a method for collecting a sample (boring core) from inside a shield tunnel to investigate the soil quality around the tunnel will be described. Fig. 1 shows an overview of the soil investigation situation. The sample collection from the ground G around the tunnel T uses the grout hole 11 of the segment 1. The segment 1 of this embodiment is a steel segment, and the grout hole 11 is erected on the skin plate of the segment 1. The soil investigation using the grout hole 11 is performed by pressing the sampler 2 into the ground from the grout hole 11 and collecting the sample taken into the sampler 2. In this embodiment, the drilling device 21 is used to press the sampler 2 into the ground G.

[0010] Fig. 2 shows the grout hole 11. As shown in Figs. 2(a) and (b), a check valve 12 for preventing the backflow of the grout material during backfill injection is installed in the grout hole 11. Therefore, when performing a soil investigation using the grout hole 11, it is necessary to remove the check valve 12. On the other hand, since the check valve 12 has grout attached to it, it is difficult to recover it manually. In addition, for the grout hole 11 after the soil investigation, since the check valve 12 has been removed, it is necessary to perform water stoppage to prevent the inflow of earth and sand from the grout hole 11 after the sampler 2 has been removed. In this embodiment, the check valve recovery device 3 is used to remove (recover) the check valve 12 installed in the grout hole 11, and the grout hole water stoppage device 4 is used to perform water stoppage after the soil investigation.

[0011] Fig. 3 shows the check valve recovery device 3. As shown in Fig. 3, the check valve recovery device 3 includes a valve 5 attached to the grout hole 11 of the segment 1, a pre-pender 6 connected to the valve 5, a rod 7 inserted through the pre-pender 6 and the valve 5, a rotational force applying means (not shown) for applying a rotational force to the rod 7, and a check valve removal jig 30 attached to the tip of the rod 7.

[0012] Valve 5 has a hollow member fixed to the end of the grout hole 11. Both ends of valve 5 have openings with a diameter larger than the inner diameter of the grout hole 11, allowing the check valve removal tool 30 to be inserted. An opening / closing member (not shown) is provided inside valve 5, and the space can be opened and closed by operating the handle 51. The prepender 6 is a cylindrical member connected to the opening on the base end side of the valve 5. The prepender 6 has an inner diameter through which the check valve removal jig 30 and the rod 7 can be inserted. The prepender 6 is also provided with a water-stopping means 61 that seals the gap between the outer surface of the rod 7 and the inner surface of the prepender 6, thereby suppressing the inflow of soil and sediment from the grout hole 11 and the backflow of treated water during soil investigation after the check valve 12 has been removed. Rod 7 extends from a rotational force application means (such as a drilling device) not shown. A connecting member 71 is fixed to the tip of rod 7, which engages with the connection portion 34 of the check valve removal jig 30.

[0013] The check valve removal tool 30 is for removing the check valve 12 installed in the grout hole 11 of segment 1. The check valve removal tool 30 is shown in Figures 4 and 5. As shown in Figures 4(a) and (b), the check valve removal tool 30 comprises a main body 31, a plurality of cutting tips 32, 32, ..., a check valve holding portion 33 provided on the inner surface of the main body 31, and a connecting portion 34 formed at the base end of the main body 31. As shown in Figures 3 and 4(a), the main body 31 is a cylindrical member having an outer diameter smaller than the inner diameter of the grout hole 11, and is insertable into the grout hole 11. The tip of the main body 31 is open. Multiple cutting tips 32, 32, ... are fixed to the tip of the main body 31. In addition, a connecting portion 34 is formed at the base end of the main body 31, which is connected to a rod 7 extending from the rotational force applying means. The rotational force of the rotational force applying means is applied to the connecting portion 34 of the main body 31 via the connecting member 71 of the rod 7. Furthermore, as shown in Figure 4(b), a check valve holding portion 33 is provided on the inner surface of the main body 31.

[0014] The cutting tip 32 cuts the outer edge of the check valve 12 as the main body 31 rotates due to the rotational force applied by the rotational force applying means. The cutting tip 32 in this embodiment is a rectangular parallelepiped metal member, as shown in Figures 4(b) and 5(a). Multiple cutting tips 32, 32, ... are provided at intervals in the circumferential direction at the tip of the main body 31, as shown in Figure 5(a). Each cutting tip 32 is inclined (for example, 10°) with respect to the central axis of the main body 31 in a side view, as shown in Figure 4(a). The cutting tip 32 is also inclined (for example, 45°) with respect to the inner surface of the main body 31, as shown in Figure 4(b). Furthermore, the cutting tip 32 is fixed to the main body 31 in a front view, as shown in Figure 5(a), in a direction along the radial direction of the main body 31 (direction along the radial direction of the main body 31) with respect to the central axis.

[0015] The check valve holding portion 33 holds the check valve 12, which has its outer edge cut off and is incorporated into the main body portion 31, to prevent it from coming out of the main body portion 31. As shown in Figures 4(b) and 5(b), the check valve holding portion 33 of this embodiment consists of a plurality of annular brushes 33a, 33b arranged in parallel along the axial direction of the main body portion 31. The plurality of annular brushes 33a, 33b arranged in parallel are arranged alternately, with different bristle lengths.

[0016] The connecting portion 34 is a nut fixed to the base end of the main body portion 31. As shown in Figures 4(a) and (b), the main body portion 31 in this embodiment has a bottom, and the connecting portion 34 is fixed to the outer surface (base end surface) of the bottom plate 35 of the main body portion 31. As shown in Figure 3, the connecting portion 34 engages with a connecting member 71 fixed to the tip of the rod 7 and transmits the rotational force of the rotational force applying means transmitted via the rod 7 to the main body portion 31. The main body portion 31 rotates due to the rotational force applied via the connecting portion 34, and the outer edge portion of the check valve 12 is cut by the cutting tip 32.

[0017] Figures 6 and 7 show the grout hole sealing device 4. As shown in Figure 6, the grout hole sealing device 4 comprises a valve 5 attached to the grout hole 11 of segment 1, a prepender 6 connected to the valve 5, a rod 7 inserted through the prepender 6 and the valve 5, and a sealing plug 40 attached to the tip of the rod 7. The valve 5, prepender 6, and rod 7 are the same as those used in the check valve recovery device 3. The connecting member 71 of the rod 7 shall be appropriately changed to a member that can engage with the water stop plug 40 (moving mechanism 44).

[0018] As shown in Figure 6, the water-stopping plug 40 is installed in the grout hole 11 of segment 1 to stop water from entering the grout hole 11. The water-stopping plug 40 comprises a water-stopping member 41 that expands laterally (increases in diameter) due to pressure from the front and rear, a pressing member 42 attached to the front of the water-stopping member 41, a retaining member 43 attached to the rear of the water-stopping member 41, and a moving mechanism 44 that moves the pressing member 42 forward and backward relative to the retaining member 43. As shown in Figures 6 and 7(b), the water-stopping member 41 is made of an elastic cylindrical member with a through hole 41a formed in the center. The water-stopping member 41 in this embodiment is made of an annular rubber material. Normally, the water-stopping member 41 has an outer diameter less than or equal to the inner diameter of the grout hole 11, and expands in diameter laterally (in the diametrical direction of the grout hole 11) when pressure is applied from the front and back (axial direction of the grout hole 11). The water-stopping member 41 may also be a hollow annular member.

[0019] As shown in Figures 6 and 7(a), the pressing member 42 is a circular plate (for example, a steel plate) attached to the front surface of the water-stopping member 41. The pressing member 42 has an outer diameter smaller than the inner diameter of the grout hole 11. The pressing member 42 is in close contact with the water-stopping member 41 when pressed against it. The pressing member 42 may be fixed to the water-stopping member 41 if necessary. The retaining member 43 is a plate (e.g., a steel plate) attached to the rear surface of the water-stopping member 41, as shown in Figures 6 and 7(c). In this embodiment, the retaining member 43 has a cross shape in front view, formed by the combination of four plate pieces 43a, 43a, ..., but the retaining member 43 may also be circular. A through hole is formed in the center of the retaining member 43, and the moving mechanism 44 (bolt 46) is configured to be inserted through it. A locking portion 45 is formed at the tip of each plate piece 43a of the retaining member 43, which can engage with the threads of the female screw 13 of the grout hole 11. The locking portion 45 is a metal piece integrally formed on the outer edge of the retaining member 43 (the tip of the plate piece 43a). Figure 8 shows the locking portion 45. As shown in Figure 8, the locking portion 45 is curved in an arc shape in cross-section, protruding outward from the outer edge of the retaining member 43 (towards the inner wall side of the grout hole 11) and extending backward (towards the tunnel interior). The tip of the locking portion 45 engages with the female thread 13 of the grout hole 11 by fitting into the groove of the female thread 13. This prevents the water-stopping plug 40 inserted into the grout hole 11 from coming out. The retaining member 43 is pressed tightly against the water-stopping member 41. The retaining member 43 may be fixed to the water-stopping member 41 if necessary.

[0020] As shown in Figure 6, the moving mechanism 44 includes a bolt 46 fixed to the pressing member 42 and a nut 47 screwed onto the bolt 46 on the rear surface of the pressing member 43. The bolt 46 is a so-called threaded rod, with one end fixed (welded) to the inner surface (the side facing the tunnel cavity) of the pressing member 42, and the other end screwed into the nut 47. The bolt 46 passes through the through hole 41a of the water-stopping member 41 and the through hole of the retaining member 43. As shown in Figure 6, the nut 47 is screwed onto a bolt 46 that passes through the water-sealing member 41 and the retaining member 43. The nut 47 engages with a connecting member 71 fixed to the tip of the rod 7 and rotates due to the rotational force of the rotational force applying means transmitted via the rod 7. As the nut 47 rotates, the bolt 46 moves axially, causing the pressing member 42 to be pulled towards the retaining member 43. This applies a pressing force in the front-rear direction to the water-sealing member 41, causing the water-sealing member 41 to expand in diameter and come into contact with the inner surface of the grout hole 11, thereby enabling water-sealing of the grout hole 11.

[0021] The following describes a soil investigation method using the grout hole 11. Figure 9 shows the procedure for the soil investigation method. As shown in Figure 9, the ground improvement method includes a cap removal step S1, an equipment installation step S2, a check valve removal step S3, a sample collection step S4, a temporary water stop step S5, an equipment removal step S6, and a cap restoration step S7. The cap removal process S1 is the process of removing the cap 14 attached to the grout hole 11, as shown in Figure 10. Since the cap 14 is screwed onto the female thread 13 of the grout hole 11, it can be removed by rotating it. A check valve 12 is installed inside the grout hole 11.

[0022] The fixture installation process S2 is the process of installing the valve 5 and prepender 6 into the grout hole 11, as shown in Figure 11. The valve 5 is installed into the grout hole 11 via an installation sleeve 52 that is installed to cover the opening of the grout hole 11. In this embodiment, the installation sleeve 52 is configured to be fixed to the grout hole 11 by screwing the sleeve body 52b into a wedge ring 52a that is arranged around the grout hole 11. The prepender 6 is installed on the end of the valve 5 opposite to the grout hole 11.

[0023] The check valve removal process S3 is the process of removing the check valve 12 installed in the grout hole 11. As shown in Figure 9, the check valve removal process S3 comprises a device insertion process S31, a cutting process S32, and a device retrieval process S33. The check valve 12 is removed using a check valve removal jig 30. Figure 12 shows the work status of the check valve removal process. The device insertion step S31 is the step of inserting the check valve removal jig 30 into the grout hole 11, as shown in Figure 12(a). The check valve removal jig 30 is inserted into the grout hole 11 through the prepender 6 and valve 5 with the rod 7 (connecting member 71) attached to the tip (see Figure 3), and the cutting tip 32 is brought into contact with the check valve 12.

[0024] As shown in Figures 12(b) and (c), cutting process S32 is a process of cutting and removing the check valve 12 using the check valve removal jig 30. In cutting process S32, the check valve 12 is cut by rotating the rod 7 while the cutting tip 32 is in contact with the check valve 12, and by pushing the rod 7 in. As shown in Figure 12(a), the outer edge of the check valve 12 installed in the grout hole 11 is cut by the rotating check valve removal jig 30. As the rod 7 is pushed in while the outer edge of the check valve 12 is being cut, the remaining part of the check valve 12, whose outer edge has been cut, is taken into the main body 31, as shown in Figure 12(c). The check valve 12 taken into the main body 31 is held in place by the check valve holding part 33. The device retrieval process S33 is the process of retrieving the check valve removal jig 30, as shown in Figure 12(d). The check valve removal jig 30 is retrieved from the grout hole 11 by pulling out the rod 7 (connecting member 71). At this time, the check valve 12 (cutting piece) that has been taken into the main body 31 is held by the check valve holding part 33 while entangled with the brushes 33a and 33b, and is therefore retrieved together with the check valve removal jig 30.

[0025] The sample collection process S4 is a process of collecting a sample from the ground G using the grout hole 11. Figure 13 shows the working status of the sample collection process. As shown in Figure 13, the sample is collected by pressing the sampler 2 into the ground through the grout hole 11 and taking the sample into the inside of the sampler 2. A drilling device 21 is attached to the sampler 2. When pressing the sampler 2 into the ground, the drilling device 21 rotates the sampler 2. Once the sampler 2 has been pressed in to a predetermined depth, the sampler 2 is retrieved. This collects the sample taken into the sampler 2. The boreholes created by sample collection are sealed by injecting mortar, grout, or other materials.

[0026] The water-stopping process S5 is the process of sealing the grout hole 11 after the sampler 2 has been recovered. Since the check valve 12 has been removed, there is a risk of groundwater, soil, etc. flowing in from the grout hole 11. Therefore, in this embodiment, the grout hole 11 is sealed with a water-stopping plug 40. As shown in Figure 9, the water-stopping process S5 includes a plug insertion process S51 and a plug expansion process S52. Figure 14 shows the water-stopping process S5. In the plug insertion step S51, as shown in Figure 14(a), the water-stopping plug 40 is inserted into the grout hole 11. The water-stopping plug 40 is inserted into the grout hole 11 through the prepender 6 and valve 5 while attached to the tip of the rod 7. When the water-stopping plug 40 is inserted into the grout hole 11, the locking portion 45 is locked into the threads of the female screw 13 of the grout hole 11 (see Figure 8). This prevents the water-stopping plug 40 from being pushed back into the interior of the grout hole 11 even if a force is applied to the water-stopping plug 40 from the ground G side. In the plug expansion step S52, as shown in Figure 14(b), the water-sealing member 41 of the water-sealing plug 40 is expanded to seal the grout hole 11 (shield the grout hole 11). The expansion of the water-sealing member 41 is achieved by using the rod 7 to rotate the nut 47, which moves the bolt 46 axially and moves the pressing member 42 toward the retaining member 43. In this way, pressure is applied to the water-sealing member 41 from the front and back, causing the water-sealing member 41 to expand. At this time, the pressing member 42 and the retaining member 43 are prevented from rotating in conjunction with the rotation of the nut 47 by the frictional force between them and the water-sealing member 41.

[0027] The equipment removal process S6 is the process of removing the valve 5, prepender 6, and rod 7 from the grout hole 11. Figure 15 shows the equipment removal process. When the valve 5, prepender 6, and rod 7 are removed from the grout hole 11, the water-stopping plug 40 remains inside the grout hole 11, as shown in Figure 15. Since the grout hole 11 is sealed by the water-stopping plug 40, the inflow of soil, groundwater, etc. from the grout hole 11 is suppressed. The cap restoration process S7 is the process of attaching the cap 14 to the grout hole 11. Figure 16 shows the cap restoration process S7. As shown in Figure 16, the cap 14 is fixed to the grout hole 11 by screwing it into the female thread 13 of the grout hole 11.

[0028] As described above, according to this embodiment, the periphery of the check valve 12 is cut using the check valve removal jig 30, and the cut check valve 12 is taken into the main body 31 and recovered. Therefore, the check valve 12 and any cut pieces of the check valve 12 are not left in the grout hole 11 or in the ground. As a result, in soil investigations using the grout hole 11 after the check valve 12 has been removed, the check valve 12 is prevented from interfering with the investigation. Furthermore, since the check valve 12 is recovered by cutting its periphery with the cutting chip 32, the check valve 12 can be recovered even if it is unable to rotate due to backfill material (grout, etc.) adhering to it.

[0029] The check valve removal jig 30 has a function (check valve holding part 33) to hold the check valve 12, which is taken into the main body 31, so that it does not come out, thus preventing the check valve 12 from being left in the ground. Furthermore, since the check valve holding section 33 is constructed by arranging brushes 33a and 33b with different bristle lengths alternately, it is possible to easily take the check valve 12 into the main body section 31 and hold the check valve 12 in a state where it is difficult for it to come out. In addition, because the check valve holding section 33 is constructed of brushes 33a and 33b with different bristle lengths, it is also possible to collect cutting fragments of various sizes that are generated when cracks or chips occur in the check valve 12 during cutting.

[0030] Furthermore, the cutting tip 32 is a rectangular carbide tip that is tilted relative to the main body 31 and fixed to the main body 31 in a orientation that aligns with the radial axis of the main body 31 when viewed from the front. As a result, the corners of the cutting tip 32 bite into the check valve 12, allowing for efficient cutting of the check valve 12. In addition, because the cutting tip 32 is tilted relative to the inner surface of the main body 31, the cut edges of the check valve 12 are easily guided into the interior of the main body 31. Furthermore, because the cutting tips 32 are arranged at intervals, the check valve 12 is easily guided into the main body 31.

[0031] Furthermore, because the water-stopping plug 40 seals off the grout hole 11 after the soil investigation, groundwater and soil will not flow in from the grout hole 11 even after the valve 5 is removed, making it easy to reinstall the cap 14. The water-stopping plug 40 can ensure high water-stopping performance by having the water-stopping member 41 expand in diameter to closely adhere to the inner circumferential surface of the grout hole 11. Furthermore, since the locking portion 45 is locked into the screw threads (spiral grooves) of the grout hole 11, the water-stopping plug 40 will not be pushed back (come out of the grout hole 11) even under high water pressure. Furthermore, since the moving mechanism 44 is composed of a bolt 46 whose tip is fixed to the pressing member 42 and a nut 47 screwed onto the bolt 46 on the rear surface of the pressing member 43, by rotating the nut 47, the pressing member 42 is pulled closer, applying a pressing force to the water-stopping member 41, and thereby expanding the diameter of the water-stopping member 41.

[0032] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and each of the above-mentioned components can be modified as appropriate without departing from the spirit of the present invention. In the above embodiment, a soil investigation using the grout hole 11 was described, but the use of the grout hole water-stopping device 4 in this embodiment is not limited to soil investigation, and for example, it may be used for ground improvement using the grout hole 11. Furthermore, the water-stopping plug 40 may also be used to stop water from entering the tunnel and drilling towards the ground using auxiliary construction methods. The water-stopping member 41 may be solid or hollow. In the above embodiment, a case in which a locking portion 45 is formed on the retaining member 43 was described, but the locking portion 45 does not necessarily have to be formed on the retaining member 43. For example, a locking member having a locking portion 45 that can be locked onto the threads of the female screw 13 of the grout hole 11 may be attached to the front or rear surface of the retaining member 43 separately from the retaining member 43. The configuration of the moving mechanism 44 is not limited and can be determined as appropriate. For example, it may include a mechanism to suppress the rotation of the retaining member 43 when the nut 47 is rotated. [Explanation of Symbols]

[0033] 1 segment 11 Grout Hall 12 Check valve 2 Samplers 3. Check valve recovery device 30 Check valve removal tool 31 Main body 32 cutting inserts 33 Check valve retaining part 34 Connection part 4. Grout hole sealing device 40 Water stop plug 41 Water-stopping member 42 Pressing member 43 Retaining member 44 Moving mechanism 45 Locking part 5 valves 51 Handle 6 Prepender 7 rods 71 Connecting member

Claims

1. A watertight plug installed in the grout hole of a segment, A water-stopping member that expands laterally due to pressure from the front and rear, A pressing member attached to the front surface of the water-stopping member, A retaining member attached to the rear surface of the water-stopping member, The system includes a moving mechanism that moves the pressing member forward and backward relative to the pressing member, The water-stopping plug is characterized in that the retaining member has a locking portion formed therein that can engage with the threads of the female screw of the grout hole in order to restrict the axial movement of the water-stopping plug when the water-stopping member is expanded.

2. A watertight plug installed in the grout hole of a segment, A water-stopping member that expands laterally due to pressure from the front and rear, A pressing member attached to the front surface of the water-stopping member, A retaining member attached to the rear surface of the water-stopping member, A moving mechanism that moves the pressing member forward and backward relative to the pressing member, The retaining member is provided with a locking member attached to it, A water-stopping plug characterized in that the locking member has a locking portion formed thereon that can be locked onto the threads of the female screw of the grout hole in order to restrict the axial movement of the water-stopping plug when the water-stopping member is expanded.

3. The water stop plug according to claim 1 or 2, characterized in that the moving mechanism comprises a bolt fixed to the pressing member and a nut screwed onto the bolt on the rear surface of the pressing member.

4. A valve attached to the grout hole of the segment, A prepender connected to the valve, The rod inserted through the prepender and the valve, A grout hole water-stopping device comprising a water-stopping plug according to claim 1 or claim 2, wherein the moving mechanism is attached to the tip of the rod.

5. A method for sealing grout holes in a segment using a water-sealing plug according to claim 1 or claim 2, wherein A valve installation process involves installing a valve and prepender into the grout hole of the segment, A plug insertion step involves inserting the water-stopping plug attached to the tip of the rod into the grout hole through the prepender and the valve, The process includes a plug expansion step for expanding the water-stopping member, In the plug insertion step, the locking portion is locked into the threads of the female screw of the grout hole. A method for sealing a grout hole, characterized in that, in the plug expansion step, the moving mechanism is operated using a rod to apply pressure from the front and rear to the water-sealing member, thereby expanding the water-sealing member and sealing the grout hole.

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