Spring water observation equipment and spring water observation methods

Abstract

To provide a spring water observation device and a spring water observation method capable of safely and efficiently determine a spring water state in front of a working face without requiring installation and recovery of a packer in a borehole using human power.SOLUTION: A spring water observation device 100 placed in a borehole B arranged in a work face K and observing spring water through introducing the spring water W from a tip of the borehole B is provided with: a packer device 20; a double pipe rod 30; a passage switching adapter 40 provided with an observation meter 48; a first check valve 50; a moving device 17 pulling out a shaft-like unit 60 formed with those; a first passage that makes the transferred water reach the inside surface of the packer 26; and a second passage that makes the spring water W introduced with the packer device 20 reach the observation meter 48, wherein the first check valve 50 opens the first passage 53 when transferring water to the packer device 20 and closes the first passage 53 when the returning water returns from the packer device 20.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a water gushing observation device and a water gushing observation method.

Background Art

[0002] In the construction of mountain tunnels, it is essential to grasp the water gushing state such as the water gushing volume and water gushing pressure in the water gushing area in front of the face and take water gushing countermeasures in advance. As a method for grasping this water gushing state, a boring hole (advance boring hole) is provided in the face, and a packer is inserted into the hole bottom while adding a rod equipped with a packer (packer rod) manually. After measuring the water gushing volume and water gushing pressure, a method of pulling out and recovering the packer rod manually is generally applied. However, this method has a problem in safety because people enter directly under the face. Also, under the situation where water gushing is drained from the boring hole, a lot of labor is required for the operation of inserting the packer and the operation of pulling out and recovering it. In particular, for a boring hole at a high place such as near the top end of the face, since it is an operation on the man cage of the drilling rig or on the bucket of the aerial work vehicle, it can be an even more difficult operation. In addition, when the water gushing pressure is high, there is a risk that the packer may spout out from the boring hole, so equipment for holding down the packer for preventing the packer from spouting out and the like is required, and it takes time and effort to grasp the water gushing state.

[0003] From the above, there is a need for a water gushing observation device and a water gushing observation method that can grasp the state of water gushing (water gushing volume, water gushing pressure, water quality, etc.) in front of the face safely and efficiently without the need for manual installation and recovery of the packer into the boring hole.

[0004] Here, in Patent Document 1, a double-pipe double-packer method that performs excavation and injection using a drill jumbo and a packer has been proposed. Specifically, this method involves inserting an inner rod, into a casing with multiple injection holes in its perimeter wall and a ring bit attached to its tip, into which an inner rod is fitted with a drilling bit that transmits impact and rotational force received from a single-pipe drilling machine to the ring bit. The inner rod, connected to the single-pipe drilling machine, and the casing are used to excavate the ground. After withdrawing the inner rod and drilling bit from the casing, a pipe with a discharge hole is inserted into the casing, and a sealing material is filled into the gap between the casing and the pipe. An injection pipe is then inserted into the pipe, which is equipped with a pair of packers separating the space inside the pipe and a discharge hole provided between these packers. With the casing installed in the ground, the injection material is supplied from the rear end of the injection pipe, and the injection material is injected into the ground through the injection hole via the discharge hole and the discharge hole. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2006-274562 [Overview of the project] [Problems that the invention aims to solve]

[0006] While the double-pipe double-packer method described in Patent Document 1 allows for the fixing of a sleeve pipe inserted into a borehole formed in the ground and an injection pipe inserted into the sleeve pipe via a packer, it does not address the aforementioned problem, namely, it does not propose a technology that eliminates the need for manual installation and retrieval of packers in boreholes and enables safe and efficient assessment of groundwater conditions ahead of the tunnel face.

[0007] The present invention aims to provide a groundwater observation device and method that eliminate the need for manual installation and retrieval of packers in boreholes, and that enable safe and efficient assessment of groundwater conditions ahead of the tunnel face. [Means for solving the problem]

[0008] To achieve the aforementioned objective, one embodiment of the spring water observation device according to the present invention is: A groundwater observation device installed in a borehole at the face of a tunnel, which collects groundwater from the tip of the borehole to perform groundwater observation, A packer device equipped with a packer, a double-tube rod attached to one end of the packer device, a flow path switching adapter attached to one end of the double-tube rod and equipped with an observation meter, and a first check valve attached to one end of the flow path switching adapter, A moving device for inserting at least a portion of a shaft-shaped unit, which is formed by the interconnection of the packer device, the double-pipe rod, the flow path switching adapter, and the first check valve, into the borehole and withdrawing the shaft-shaped unit from the borehole, A first channel is provided inside the axial unit to allow the supplied water to reach the inner surface of the packer, The packer device, the double-tube rod, and the flow path switching adapter are provided with a second flow path that allows the spring water taken in by the packer device to reach the observation meter, The first check valve is characterized by opening the first flow path when supplying water to the packer device and closing the first flow path when return water returns from the packer device.

[0009] According to this embodiment, a moving device is provided to insert at least a part of an axial unit, which consists of a packer device, a double-pipe rod, a flow path switching adapter equipped with an observation meter, and a first check valve connected to each other, into a borehole and withdraw it from the borehole. Two water flow systems are provided: a first flow path that brings the supplied water to the inner surface of the packer, and a second flow path that brings the collected spring water to the observation meter. By measuring physical quantities indicating the state of the spring water with the observation meter, the manual installation (insertion and expansion) and retrieval of the packer into the borehole are eliminated, and the state of spring water ahead of the tunnel face can be grasped safely and efficiently. Furthermore, the first check valve opens the first channel when supplying water to the packer device and closes the first channel when return water returns from the packer device, thereby ensuring both the necessary amount of water is supplied to the packer device and the packer pressure is maintained after the packer opens.

[0010] Here, the physical quantities indicating the state of the spring water include the spring water volume and spring water pressure. Furthermore, in this embodiment, in addition to measuring the physical quantities of the spring water that reach the observation meter, "observation" also includes water quality observation such as turbidity of the spring water and groundwater level observation, and therefore, the physical quantities and water quality of the spring water are the objects of observation. Observation data (measurement data) from the observation meter may be acquired after the axial unit is retrieved, or it may be transmitted in real time from the observation meter via wireless communication to various portable terminals and computers, such as a portable terminal in the operator's cabin of a trolley equipped with a mobile device, a portable terminal carried by the person performing the measurement, or a computer in a management facility outside the tunnel. Furthermore, the double-walled rod may consist of one or more sections, and depending on the length of the borehole, for example, multiple double-walled rods may be joined together sequentially. Furthermore, the mobile device may be a hydraulic cylinder mounted on a dump truck or aerial work platform, or a drilling machine for drilling boreholes, and various forms can be applied that eliminate the need for manual installation of double-pipe rods or packers into boreholes. Furthermore, "inserting at least a portion of the axial unit into the borehole" includes not only inserting the entire axial unit, but also inserting only the packer device and (part of) the double-tube rod, etc., but in actual operation, the latter is generally applied. After the groundwater observation is completed, when draining the water to deflate the packer and recovering the packer device from the borehole, for example, a pushing force or pulling force (both opposite forces along the longitudinal direction of the axial unit) can be applied to the first check valve to open the middle of the first flow path and drain the water.

[0011] Furthermore, the groundwater observation device of this embodiment can be applied to boreholes of various lengths, such as ultra-long boreholes of about 1000m in length, medium boreholes of about 100m in length, and short boreholes of about 30m in length.

[0012] Furthermore, another embodiment of the spring water observation device according to the present invention is: A drilling machine comprising a trolley, a boom rotatably mounted on the trolley, a guide shell mounted on the tip of the boom, a drifter that slides along the guide shell, a shank rod mounted on the tip of the drifter, and a water supply means for supplying water to the shank rod, characterized in that the drifter and the shank rod form the moving device, the axial unit is directly or indirectly connected to the shank rod, and water is supplied from the water supply means to the first channel.

[0013] According to this embodiment, a moving device is formed by the guide shell, drifter, and shank rod of the drilling machine, and the axial unit is inserted into the borehole by the drifter sliding along the guide shell, thereby allowing the axial unit to be stably inserted into the borehole and stably retrieved from the borehole after observation. Furthermore, for example, after drilling a borehole with the drilling machine, the axial unit can be continuously installed in the borehole with the drilling machine to efficiently measure physical quantities related to the state of groundwater. Furthermore, since the drilling machine is equipped with its own water supply means, including a water pump, water tank, and water pipe, and operates the water supply means to supply water as needed when drilling a borehole, it is preferable to use the water supply means provided by the drilling machine, as this eliminates the need for a water supply means specific to the groundwater observation device. As a drilling machine, the Drill Jumbo (registered trademark), which has multiple booms mounted on the front of a trolley that can be rotated and extended, can be used. In addition, "the axial unit is directly or indirectly connected to the shank rod" means that, in addition to the first check valve forming the axial unit being directly connected to the shank rod, a push-in tube or a special-shaped connector connected to the first check valve is connected to the shank rod. Therefore, it includes the case where the axial unit is indirectly connected to the shank rod.

[0014] When the water gushing pressure is relatively small and the installation state of the axial unit in the boring hole can be maintained only by the pressing force of the packer against the hole wall of the boring hole, the first check valve can be disconnected from the shank rod and the drilling machine can be applied to other uses (such as drilling other boring holes). On the other hand, when the water gushing pressure is relatively large and the installation state of the axial unit in the boring hole cannot be maintained only by the pressing force of the packer against the hole wall of the boring hole, it is advisable to wait for the drilling machine in front of the face until the water gushing observation is completed, and hold the axial unit from the rear with the drifter and the shank rod.

[0015] Another aspect of the water gushing observation device according to the present invention is It further includes a special-shaped connector interposed between the shank rod and the first check valve.

[0016] According to this aspect, since a special-shaped connector (or a caliber conversion connector) is interposed between the shank rod of the drilling machine and the first check valve, it becomes possible to connect the first check valve according to the caliber of the shank rod specific to the model of the drilling machine.

[0017] In another aspect of the water gushing observation device according to the present invention, A front centralizer and a rear centralizer are respectively mounted at the tip of the guide shell and behind the tip. It further includes a push-in tube interposed between the special-shaped connector and the first check valve. The first check valve is located closer to the face side than the front centralizer.

[0018] According to this aspect, by interposing a push-in tube between the non-standard connector and the first check valve, the first check valve and the flow path switching adapter can be positioned in front of the front centralizer in the guide shell. The first check valve and the flow path switching adapter are positioned near the face of the borehole. In other words, the shaft unit can be installed in the boring hole so that a long member does not protrude from the face of the borehole, thereby suppressing interference with other face operations.

[0019] Here, the guide shell of the drilling machine generally has two centralizers (front centralizer and rear centralizer) equipped with hydraulic clamps, which have the function of centering the drilling rod and the function of gripping the drilling rod with the hydraulic clamp provided in the centralizer. In this aspect, when gripping the shaft unit using these two centralizers and inserting it into the boring hole while centering, by using a push-in tube such as a steel pipe, the first check valve and the flow path switching adapter behind the shaft unit can be positioned closer to the face side than the front centralizer.

[0020] Also, in another aspect of the water gushing observation device according to the present invention, A water pressure measuring device for measuring at least the water pressure in the first flow path is interposed between the flow path switching adapter and the first check valve. The water pressure measuring device includes a main flow path forming the first flow path and a branch flow path branched from the main flow path. A seat cutting groove is provided on the outer surface of the water pressure measuring device. A second check valve is interposed in the middle of the branch flow path so that the second check valve closes the branch flow path when water is sent to the packer device. A check valve is attached to the seat cutting groove, and the water pressure in the first flow path is measured.

[0021] According to this embodiment, a water pressure measuring device is interposed between the flow path switching adapter and the first check valve to measure the water pressure in the first flow path, thereby enabling the measurement of the water pressure in the first flow path and the water pressure in the packer communicating with the first flow path (both of the same value), and confirming whether the packer is being maintained at the desired water pressure.

[0022] Furthermore, the water pressure measuring device includes a main channel forming the first channel and branch channels branching off from the main channel, with a second check valve interposed in the middle of the branch channel so that the second check valve closes the branch channel when water is supplied to the packer device, thereby ensuring the liquid-tightness of the first channel when water is supplied to the packer device.

[0023] Furthermore, a counterbore groove is provided on the outer surface of the water pressure measuring device, a check valve is attached to the counterbore groove, and a pressure gauge is attached to the check valve. This allows the second check valve to be opened by the check valve, making it possible to measure the water pressure in the first flow path with the pressure gauge. When inserting the shaft unit into the borehole, the check valve and pressure gauge are not attached to the counterbore groove, thus preventing them from interfering with the centralizer.

[0024] Furthermore, another embodiment of the spring water observation device according to the present invention is: The water pressure measuring device is equipped with the check valve, which is configured to further perform at least one of the following: supplying additional water to the first flow path or draining water from the first flow path.

[0025] According to this embodiment, in addition to the measurement of water pressure in the first channel by attaching a check valve to the water pressure measuring device and a pressure gauge to the check valve, various functions can be given to the water pressure measuring device by further performing additional water supply to the first channel or drainage from the first channel. For example, if the water pressure required for the packer is insufficient as a result of measuring the water pressure in the first channel, a water supply means can be connected to the check valve and additional water can be supplied to the first channel to increase the pressure inside the packer. Furthermore, when draining the packer to deflate it after the groundwater observation is completed and retrieving the packer device etc. from the borehole, the second check valve is opened by installing a check valve in the counterbore groove, making it possible to drain the water through the branch channel and through the check valve.

[0026] Furthermore, another embodiment of the spring water observation device according to the present invention is: The first check valve and the water pressure measuring device are integrated into a single unit, and the branch flow path is provided on the flow path switching adapter side of the first check valve.

[0027] According to this embodiment, the first check valve and the water pressure measuring device are integrated into a single unit, which is preferable because it allows for the enjoyment of various functions provided by the water pressure measuring device while suppressing an increase in the number of parts.

[0028] Furthermore, one embodiment of the spring water observation method according to the present invention is: A method for observing groundwater by collecting groundwater from the tip of a borehole installed at the tunnel face, The apparatus installation process involves: an axial unit comprising a packer device equipped with a packer, a double-tube rod, a flow path switching adapter equipped with an observation meter, and a first check valve, all interconnected; a first flow path that allows water supplied inside the axial unit to reach the inner surface of the packer; and a second flow path that allows groundwater taken in by the packer device to reach the observation meter, wherein at least a portion of the axial unit is inserted into the borehole by a moving device; the packer device is positioned at or near the tip of the borehole; and the packer is expanded laterally by water supplied through the first flow path, pressing the packer against the borehole wall; An observation process in which seepage water is taken in from the tip of the borehole via the second channel and brought to the observation instrument, and seepage water observation is performed, The device is characterized by having a device retrieval step, which involves draining the packer through the first channel to deflate it, and then using the moving device to pull out and retrieve the axial unit from the borehole.

[0029] According to this embodiment, at least a portion of an axial unit, which consists of a packer device, a double-pipe rod, a flow path switching adapter equipped with an observation meter, and a first check valve connected to each other, is inserted into the borehole using a moving device. After the packer is inflated laterally to install the axial unit in the borehole, groundwater is taken in from the tip of the borehole and observed using the observation meter. After the observation, the axial unit is pulled out of the borehole using the moving device and recovered. This eliminates the need for manual installation and recovery of the packer in the borehole, making it possible to safely and efficiently grasp the state of groundwater ahead of the tunnel face.

[0030] Furthermore, in another embodiment of the spring water observation method according to the present invention, In the aforementioned device installation process, A drilling machine comprising a trolley, a boom rotatably mounted on the trolley, a guide shell mounted on the tip of the boom, a drifter that slides along the guide shell, a shank rod mounted on the tip of the drifter, and a water supply means for supplying water to the shank rod, The guide shell, the drifter, and the shank rod form the moving device, and the axial unit is connected directly or indirectly to the shank rod. The method is characterized by advancing the drifter toward the face to push in the packer device and the double-tube rod, retracting the drifter to add a new double-tube rod, and then advancing the drifter toward the face again.

[0031] According to this embodiment, a moving device is formed using the guide shell, drifter, and shank rod of the drilling machine, and by sliding the drifter along the guide shell, the axial unit is inserted into the borehole, thereby allowing the axial unit to be stably inserted into the borehole and stably retrieved from the borehole after observation, as well as allowing for smooth extension of the double-tube rod. Furthermore, for example, after drilling a borehole with a drilling machine, an axial unit can be continuously installed in the borehole using the same drilling machine, allowing for efficient observation of physical quantities related to the state of groundwater, water quality, and other parameters. [Effects of the Invention]

[0032] According to the groundwater observation device and method of the present invention, the manual installation and retrieval of packers in boreholes is unnecessary, and the groundwater conditions ahead of the tunnel face can be grasped safely and efficiently. [Brief explanation of the drawing]

[0033] [Figure 1] This is a perspective view of an example of a drilling machine equipped with a mobile device that forms a spring water observation device according to the embodiment. [Figure 2] This is a perspective view of an example of a spring water observation device according to an embodiment. [Figure 3] This is an exploded longitudinal cross-sectional view of a spring water observation device according to an embodiment, comprising a packer device, a double-pipe rod, a flow path switching adapter equipped with an observation meter, and a first check valve, showing both the water flow in the first flow path and the spring water flow in the second flow path. [Figure 4] This is a view along the line IV-IV in Figure 3, showing a cross-sectional view of the arrangement of the first and second flow paths in the flow path switching adapter. [Figure 5] This is a process diagram of an example of a spring water observation method according to the embodiment. [Figure 6] Following Figure 5 is a process diagram of an example of a spring water observation method according to the embodiment. [Figure 7] Following Figure 6 is a process diagram of an example of a spring water observation method according to the embodiment. [Figure 8] Following Figure 7 is a process diagram of an example of a spring water observation method according to the embodiment. [Figure 9] Following Figure 8 is a process diagram of an example of a spring water observation method according to the embodiment. [Figure 10] Following Figure 9 is a process diagram of an example of a spring water observation method according to the embodiment. [Figure 11] Following Figure 10 is a process diagram of an example of a spring water observation method according to the embodiment. [Figure 12] This figure illustrates another example of the spring water observation method according to the embodiment, in which spring water observation is performed while measuring the water pressure of the first channel. [Figure 13A] This is a longitudinal cross-sectional view illustrating a situation where a check valve is not installed in the counterbore groove of a water pressure measuring device. [Figure 13B] This is a longitudinal cross-sectional view illustrating the state in which a check valve is installed in the counterbore groove of a water pressure measuring device. [Modes for carrying out the invention]

[0034] The spring water observation device and spring water observation method according to the embodiment will be described below with reference to the attached drawings. In this specification and drawings, substantially identical components may be denoted by the same reference numerals to avoid redundant explanations.

[0035] [Spring water observation device according to the embodiment] First, an example of a spring water observation device according to an embodiment will be described with reference to Figures 1 to 4. Here, Figure 1 is a perspective view of an example of a drilling machine equipped with a mobile device that forms a spring water observation device according to the embodiment, and Figure 2 is a perspective view of an example of a spring water observation device according to the embodiment. Figure 3 is an exploded longitudinal cross-sectional view of a packer device, a double-pipe rod, a flow path switching adapter equipped with an observation meter, and a first check valve that constitute the spring water observation device according to the embodiment, showing both the water flow in the first flow path and the spring water flow in the second flow path, and Figure 4 is a view taken along the line IV-IV in Figure 3, which is a cross-sectional view of the arrangement of the first flow path and the second flow path in the flow path switching adapter.

[0036] The groundwater observation devices and methods described below are used in mountain tunnel construction to understand the state of groundwater, such as the amount and pressure of groundwater in the groundwater-splashing section ahead of the tunnel face. Based on the observation results, it is possible to determine whether or not groundwater countermeasures should be implemented in advance of the next tunnel excavation, and to obtain observation results that can be used when considering the impact on the surrounding environment. For example, if a large amount of groundwater is generated at high pressure during the construction of a mountain tunnel, it can have a significant impact not only on the tunnel construction, including face collapse, but also on the surrounding environment (ground subsidence, groundwater level drop, etc.), making necessary countermeasures essential.

[0037] For groundwater observation, the advance boreholes constructed at the tunnel face include ultra-long boreholes of about 1000m in length, medium boreholes of about 100m in length, and short boreholes of about 30m in length. Any of these forms may be applied to the borehole constructed when performing the groundwater observation method according to this embodiment.

[0038] In this type of groundwater observation using ultra-long boreholes, the presence or absence of groundwater, as well as its location, are investigated. However, it can take several months to approach the groundwater zone, and the investigation requires large-scale equipment. In contrast, in groundwater observation using medium-length or short-length boreholes, the packer provided in the groundwater observation device according to the embodiment can be used to accurately measure groundwater pressure and groundwater volume, making it possible to confirm the permeability of the ground and predict the amount of groundwater that will be reached when the tunnel face is reached. Furthermore, in groundwater observation using short boreholes, as explained below, groundwater observation can be carried out using a drilling machine permanently stationed at the tunnel face, resulting in lower costs for groundwater observation. The time required to drill a single borehole is only about 1 to 2 hours, and it is possible to quickly drill multiple boreholes.

[0039] For these reasons, the spring water observation device and spring water observation method according to the embodiment are preferably used for spring water observation using medium-length boreholes and short boreholes, and are particularly desirable for spring water observation using short boreholes. Currently, the only method for measuring groundwater pressure using short boreholes is to manually install a packer device. As explained earlier, there is room for improvement in terms of safety and efficiency during observation construction. Therefore, the groundwater observation device and method according to the embodiment described below can be a technology that enhances construction safety and efficiency in groundwater observation construction using short boreholes.

[0040] The drilling machine 10 shown in Figure 1 is a drill jumbo and has a trolley 11 equipped with a cabin, a travel mechanism, and a water supply means (consisting of a water pump, water tank, and water pipe, etc.) not shown, and a plurality of booms 12 (five in the illustrated example) mounted in front of the trolley 11 so as to be rotatable in the horizontal direction X1 (around the yaw axis) and the vertical direction X2 (around the pitch axis), and each boom 12 is extendable and retractable in the axial direction X3.

[0041] Of the multiple booms 12, a man cage 13 is rotatably mounted on the tip of boom 12B, and the work platform of the man cage 13 is configured to maintain a horizontal position at all times in accordance with the rotation of boom 12B.

[0042] Meanwhile, a guide shell 14 is attached to the tip of the other boom 12A, and a drifter 15 is slidably mounted on the guide shell 14. A shank rod 16 is attached to the tip of the drifter 15, and water is supplied from a water supply means (not shown) equipped on the trolley 11 to a flow path (not shown) inside the shank rod 16.

[0043] Furthermore, an annular forward centralizer 18A is attached to the tip of the guide shell 14, and an annular rear centralizer 18B is attached behind it, with a shank rod 16 slidably inserted through the inside of the two centralizers 18A and 18B.

[0044] The guide shell 14, the drifter 15, and the shank rod 16 constitute the moving device 17. Here, the drifter 15 can not only slide on the guide shell 14 but also rotate around its axis.

[0045] As shown in Figure 2, the shaft unit 60 is formed by, in order from the face side, a packer device 20 equipped with a packer 26, a double-tube rod 30 attached to the rear end of the packer device 20, a flow path switching adapter 40 attached to the rear end of the double-tube rod 30, and a first check valve 50 attached to the rear end of the flow path switching adapter 40. As shown in Figure 3, an observation meter 48 is attached to the flow path switching adapter 40 via an inlet pipe 46. In addition, depending on the length of the borehole, another double-tube rod may be added as an extension pipe to the rear end of the double-tube rod 30.

[0046] An irregularly shaped connector 80 is attached to the tip of the shank rod 16 that forms the moving device 17, a push-in pipe 70 is attached to the tip of the irregularly shaped connector 80, and the rear end of the first check valve 50 is connected to the tip of the push-in pipe 70, thereby forming the spring water observation device 100.

[0047] Since the diameter of the shank rod 16 changes depending on the model of the drilling machine 10, the interposition of the irregularly shaped connector 80 makes it possible to connect the first check valve 50 according to the diameter of the shank rod 16.

[0048] As will be explained in detail below, when inserting the packer device 20 and double-tube rod 30 (part or all of them), which are part of the axial unit 60, into a borehole formed in the ground, the drilling machine 10 is positioned in front of the face, and the boom 12A is positioned in front of the borehole. Then, the drifter 15 slides in the X5 direction along the guide shell 14 that constitutes the moving device 17, thereby inserting the packer device 20 and double-tube rod 30 into the borehole in the X6 direction.

[0049] Water supplied to the shaft-shaped unit 60 via the water supply means equipped on the trolley 11 causes the packer 26 of the packer device 20 to expand laterally, pressing against the borehole wall, thereby completing the installation of the shaft-shaped unit 60 into the borehole.

[0050] A portion of the sampling tube 22 protrudes from the tip of the packer device 20, and through this sampling tube 22, groundwater from inside the borehole is drawn into the shaft-shaped unit 60.

[0051] Furthermore, by inserting the push-in pipe 70, which is used to fully insert the axial unit 60 into the borehole, through the front centralizer 18A and the rear centralizer 18B, the first check valve 50 and the flow path switching adapter 40 that form the axial unit 60 can be positioned closer to the drilling face than the front centralizer 18A. After a portion of the axial unit 60 is installed in the borehole, for example, the push-in pipe 70 and the irregular connector 80 can be disconnected, and the drilling machine 10 can be used for other purposes.

[0052] In this example, the spring water observation device 100 is equipped with a guide shell 14 and a drifter 15 of the drilling machine 10 as a moving device 17, but it may also be equipped with a hydraulic cylinder mounted on an aerial work platform or the like as a moving device.

[0053] Next, with reference to Figures 3 and 4, the specific configurations of each component constituting the axial unit 60 will be described.

[0054] The packer device 20 is formed by fitting left and right annular main pipes 21B and 21C to both ends of a central annular main pipe 21A. A sealing material 24, such as an O-ring, is interposed in the fitting portion between the main pipe 21A and the left and right main pipes 21B and 21C, and the main pipes 21B and 21C are connected to the left and right ends of the main pipe 21A while sliding in contact with the sealing material 24.

[0055] The main pipe 21A is divided into two parts, left and right, with a packer mounting opening 21c provided between them. A packer 26 is positioned in the packer mounting opening 21c, and the left and right ends of the packer 26 are fitted into mounting grooves 21d at the ends of the left and right main pipes 21A, and are fixed in place so as to be able to slide freely. In other words, when the packer 26 expands laterally, the ends of the packer 26 are pulled and slide within the mounting grooves 21d, but because of the grooves, the packer 26 will not come off.

[0056] A sampling tube 22 is inserted inside the main pipes 21A, 21B, and 21C, with a portion of the sampling tube 22 protruding from the tip 21a of the main pipe 21C. A second channel 23 is provided inside the sampling tube 22, and spring water is drawn in from the tip of the second channel 23 in the direction of Y10. The drawn-in spring water flows through the second channel 23 in the direction of Y11 and is sent to the double-pipe rod 30.

[0057] An annular first channel 25 is provided between the main pipe 21 and the sampling pipe 22. Water supplied from the double-pipe rod 30 flows through the first channel 25 in the Y6 direction and reaches the packer mounting opening 21c, pressing laterally against the inner surface of the packer 26, causing the packer 26 to bulge laterally in the Y7 direction. The laterally bulging packer 26 presses against the borehole wall with a predetermined pressure, making it possible to maintain the installation position of the axial unit 60 inside the borehole even when subjected to groundwater pressure from the groundwater. If the groundwater pressure is too high, the moving device 17 of the drilling machine 10 can be kept attached to the axial unit 60 to maintain the installation position of the axial unit 60 inside the borehole.

[0058] The tip 31a of the outer tube 31, which constitutes the double-tube rod 30, is fitted into the rear end 21b of the main tube 21B.

[0059] The double-tube rod 30 has an outer tube 31 and an inner tube 32, with an annular first flow path 35 provided between them, which communicates with the first flow path 25 of the packer device 20. In addition, a second flow path 33 is provided inside the inner tube 32, which communicates with the second flow path 23 of the packer device 20.

[0060] A sealing material 34, which is an O-ring, is provided at the tip end of the outer tube 31. The rear end 21b of the packer device 20 is fitted onto the tip 31a of the outer tube 31, and the two are connected while sliding against the sealing material 34.

[0061] The spring water flowing through the second channel 23 of the packer device 20 flows into the second channel 33 of the inner pipe 32 in the Y12 direction and flows through the second channel 33 in the Y13 direction. Meanwhile, the water supplied from the channel switching adapter 40 flows through the first channel 35 in the Y5 direction and is sent to the first channel 25 of the packer device 20.

[0062] The tip 41a of the main pipe 41, which constitutes the flow path switching adapter 40, is fitted into the rear end 31b of the outer pipe 31. Here, although not shown in the diagram, if another double pipe rod is added to the double pipe rod 30 as an extension pipe, the tip of the extension pipe will be connected to the rear end 31b of the double pipe rod 30 shown in the diagram.

[0063] The flow path switching adapter 40 has a main pipe 41. As shown in Figures 3 and 4, a second flow path 43 is provided in the center of the main pipe 41, and multiple (seven in the illustrated example) first flow paths 45 are provided around it. The second flow path 43 communicates with the second flow path 33 of the double-walled rod 30, and the multiple first flow paths 45 communicate with the annular first flow path 35 of the double-walled rod 30.

[0064] A sealing material 44, which is an O-ring, is provided at the tip end of the main pipe 41, and the rear end 31b of the double-tube rod 30 is fitted onto the tip 41a of the main pipe 41, and the two are connected while sliding against the sealing material 44.

[0065] In the main pipe 41, the second flow channel 43 bends at its end to form a mounting opening 43a facing a part of the side surface of the main pipe 41. One end of the inlet pipe 46 is attached to this mounting opening 43a, and the observation meter 48 is mounted on the other end of the inlet pipe 46.

[0066] The spring water that flows into the second channel 43 via the second channel 33 of the double-walled rod 30 flows through the second channel 43 in the Y14 direction, is introduced into the inlet pipe 46 in the Y15 direction, and then reaches the observation meter 48. The observation meter 48 is a pressure gauge for measuring the spring water pressure, a flow meter for measuring the spring water volume, etc., and measures physical quantities such as the spring water pressure and volume of the incoming spring water. Although not shown in the diagram, for example, a spring water outlet may be provided in the middle of the inlet pipe 46, and the spring water may be discharged to allow visual inspection of the water quality, including its turbidity.

[0067] If the observation instrument 48 is equipped with a communication means (not shown), the observation data is transmitted in real time via the communication means to a portable terminal in the operator's cabin of the drilling machine 10, or to a computer in a management facility outside the tunnel.

[0068] Meanwhile, the water supplied from the first check valve 50 flows into a plurality of first flow channels 45 in the main pipe 41, flows through each first flow channel 45 in the Y4 direction, and is sent to the first flow channel 35 of the double pipe rod 30.

[0069] The tip 51a of the main pipe 51 that constitutes the first check valve 50 is fitted into the rear end 41b of the flow path switching adapter 40.

[0070] The first check valve 50 has a main pipe 51. A valve seat 52 with a hollow 52b inside is provided in the center of the main pipe 51, and a first flow path 53 that communicates with the opening 52a of the hollow 52b is connected to the tip 51a of the main pipe 51.

[0071] A sealing material 51c, which is an O-ring, is provided at the tip end of the main pipe 51, and the rear end 41b of the flow path switching adapter 40 is fitted onto the tip 51a of the main pipe 51, and the two are connected while sliding contact is made with the sealing material 51c.

[0072] A spring 54 is provided on the outer circumference of the first flow path 53, and the spring 54 biases the rubber bulb 55 to close the opening 52a of the valve seat 52. The first flow path 53 is in communication with the hollow 52b of the valve seat 52, and a hollow push-in pipe 70 or the like is connected to the rear end 51b of the first check valve 50. Water supplied from a water supply means (not shown) flows through the hollows of the shank rod 16, the irregular connector 80, and the push-in pipe 70 and flows into the first flow path 53 of the first check valve 50 in the Y1 direction.

[0073] When the water pressure of the incoming water exceeds the biasing force of the spring 54, the rubber bulb 55 moves in the Y2 direction, opening the opening 52a, and water flows through the opening 52a through the first flow path 53 on the flow path switching adapter 40 in the Y3 direction and into the first flow path 45 of the flow path switching adapter 40.

[0074] Once the packer 26 has fully expanded inside the borehole and the axial unit 60 has been installed in the borehole, the water supply from the water supply means is stopped. This cessation of water supply eliminates the force pushing the rubber ball 55 from the rear, causing the rubber ball 55 to move due to the biasing force of the spring 54 and closing the opening 52a of the valve seat 52.

[0075] By closing this opening 52a, the return water in the Y16 direction is prevented from being drained through the opening 52a, thereby retaining the water filling the first flow path of each member, and making it possible to maintain the pressing force of the packer 26 that is expanding and pressing against the borehole wall.

[0076] Furthermore, when the observation is completed and the packer 26 is to be deflated, the water is drained by applying a pushing force or pulling force (both opposing forces along the longitudinal direction of the axial unit) to the first check valve 50, thereby opening the middle of the first flow path.

[0077] According to the spring water observation device 100, the mobile device 17 is formed by a guide shell 14 etc. that is pre-equipped on the boom 12A of the drilling machine 10, and furthermore, by using a water supply means pre-equipped on the trolley 11 to inflate the packer 26 of the packer device 20, it becomes unnecessary to prepare a mobile device and water supply means specific to the spring water observation device 100.

[0078] Furthermore, since the drilling machine 10 can install a portion of the axial unit 60 into the borehole in a manner that is continuous with the drilling of the borehole, it becomes possible to perform a series of operations from borehole drilling to groundwater observation in an extremely efficient manner.

[0079] Furthermore, since the operator can install the axial unit 60 into the borehole, perform subsequent seepage observations, and retrieve the axial unit 60 from the borehole after seepage observations while the operator is on board the drilling machine 10, it eliminates the need for manual installation and retrieval of packers into the borehole, making it possible to safely understand the seepage conditions ahead of the tunnel face.

[0080] [Method for observing spring water according to an embodiment] Next, an example of a groundwater observation method according to the embodiment will be described with reference to Figures 5 to 11. Here, Figures 5 to 11 are, in order, process diagrams of an example of a groundwater observation method according to the embodiment. In the following description, the packer device 20, etc., is inserted into the borehole B using the moving device 17 of the drilling machine 10 shown in Figure 1, but the illustration of the carriage 11 of the drilling machine 10, etc., is omitted.

[0081] First, as shown in Figure 5, a borehole B is drilled into the tunnel face K of a mountain tunnel or similar tunnel constructed in the natural ground G using the drilling machine 10 shown in Figure 1. The advanced borehole B shown in the illustration will be described below as a short borehole with a length of approximately 30 m.

[0082] The moving device 17 is composed of a guide shell 14, a drifter 15, and a shank rod 16. An irregularly shaped connector 80 is attached to the tip of the shank rod 16, and a flow path switching adapter 40 is attached to the tip of the irregularly shaped connector 80. A double-pipe rod 30 and a packer device 20 are connected in order in front of it. The packer device 20 and the double-tube rod 30 are inserted through the front centralizer 18A and the rear centralizer 18B located on the guide shell 14. The double-tube rod 30 and the other components are gripped and centered by these centralizers 18A and 18B, and then inserted into the borehole B.

[0083] Next, as shown in Figure 6, the drifter 15 is slid along the guide shell 14 toward the face in the X5 direction, thereby inserting the packer device 20 and the double-tube rod 30 into the borehole B in the X6 direction in that order.

[0084] Here, if the length of the double-tube rod 30 is shorter than the length of the borehole B, as shown in the illustrated example, once the double-tube rod 30 has been inserted into the borehole B, the drifter 15 is slid to the opposite side of the working face to create a gap between the rear end of the double-tube rod 30 and the flow path switching adapter 40. Next, an extension pipe 30A, which is made of a separate double-tube rod, is inserted into this gap, and both ends of the extension pipe 30A are connected to the double-tube rod 30 and the flow path switching adapter 40. Then, the drifter 15 is slid again towards the working face in the X5 direction, so that the extension pipe 30A is also inserted into the borehole B in the X6 direction, as shown in Figure 6.

[0085] For example, for a borehole B with a length of approximately 30m, it is desirable to have double-walled rods 30 and extension pipes 30A available in various lengths such as 0.5m, 1m, 1.5m, and 3m.

[0086] When adding the extension pipe 30A, the centralizers 18A and 18B grip the double-walled rod 30, and the extension pipe 30A inserted behind it is rotated by the rotational movement of the drifter 15 while the two are connected (screwed together).

[0087] As shown in Figure 6, even when the guide shell 14 is brought as close as possible to the face K and the drifter 15 is slid as far as possible toward the face, there are often cases where the packer device 20 cannot be inserted close to the tip of the borehole B.

[0088] Therefore, as shown in Figure 7, the connection between the flow path switching adapter 40 and the irregular connector 80 is released, and first, the first check valve 50 is connected to the flow path switching adapter 40, and then the push-in pipe 70 is connected to both the first check valve 50 and the irregular connector 80.

[0089] This connection forms an axial unit 60 consisting of a packer device 20, a double-pipe rod 30, an extension pipe 30A, a flow path switching adapter 40, and a first check valve 50, and the packer device 20 can be inserted by the push pipe 70 to a predetermined position near the tip of the borehole B.

[0090] As shown in Figure 7, after inserting the packer device 20, the double-pipe rod 30, and a portion of the extension pipe 30A (a portion of the axial unit 60) into the borehole B, the packer 26 is expanded laterally in the Y7 direction by water supplied from a water supply means (not shown). The expanded packer 26 then presses against the borehole wall of the borehole B with a predetermined pressing force, thereby completing the installation of the axial unit 60 into the borehole B.

[0091] Next, as shown in Figure 8, the connection between the push-in pipe 70 and the irregular-shaped connector 80 is released, and the drilling machine 10, including the mobile device 17, is retracted. The retracted drilling machine 10 is then used for other purposes, such as drilling a separate boring hole B.

[0092] The illustrated example is a case where the expected groundwater pressure is relatively small, and the pressing force applied to the borehole wall of borehole B by the packer 26 alone is sufficient to maintain the installation state of the axial unit 60 within borehole B. Therefore, for example, in cases where the expected groundwater pressure is relatively high and the pressing force on the borehole wall of borehole B by the packer 26 alone is insufficient to maintain the position of the axial unit 60 within borehole B, it is preferable to keep the drilling machine 10 waiting in front of the face K until the groundwater observation is completed, and to hold the axial unit 60 from the rear with the drifter 15 and shank rod 16 (the above describes the device installation process).

[0093] Next, as shown in Figure 9, an observation meter 48 is attached to the flow path switching adapter 40, and the spring water W seeping into the borehole B is taken in and guided to the observation meter 48 to observe the spring water pressure and flow rate of the spring water W. Here, the observation targets include not only physical quantities such as spring water pressure, but also the water quality of the spring water and the groundwater level.

[0094] Observation data (measurement data) from the observation instrument 48 may be acquired after the axial unit 60 has been retrieved, or, if the observation instrument 48 is equipped with wireless communication means, the data may be transmitted in real time via wireless communication to a portable terminal in the operator's cabin of the bogie 11 of the drilling machine 10, or to a computer in a management facility outside the tunnel (observation process).

[0095] After the spring water observation is completed, as shown in Figure 10, the drilling machine 10 is brought close, the irregular connector 80 is connected to the push-in pipe 70, and the water that was inflating the packer 26 is drained, causing the packer 26 to deflate in the Y8 direction.

[0096] Next, as shown in Figure 11, the drifter 15 is slid along the guide shell 14 in the X7 direction away from the face K, thereby pulling out and recovering the packer device 20, double-tube rod 30, etc., from the borehole B in the X8 direction (this completes the device recovery process).

[0097] The illustrated groundwater observation method eliminates the need for manual installation and retrieval of packers in boreholes, allowing for safe and efficient assessment of groundwater conditions ahead of the tunnel face. This technology can dramatically improve construction safety and efficiency, particularly in groundwater observation work using short boreholes to measure groundwater pressure and other parameters.

[0098] [Modification of the spring water observation method according to the embodiment] Next, with reference to Figures 12 to 13B, a modified example of the spring water observation method according to the embodiment will be described. Here, Figure 12 is a diagram illustrating a method for observing spring water while measuring the water pressure of the first channel, in another example of the spring water observation method according to the embodiment. Figure 13A is a longitudinal cross-sectional view illustrating a state in which a check valve is not installed in the counterbore groove of the water pressure measuring device, and Figure 13B is a longitudinal cross-sectional view illustrating a state in which a check valve is installed in the counterbore groove of the water pressure measuring device.

[0099] The modified version of the spring water observation method shown in the figure differs from the example of the spring water observation method already described with reference to Figures 5 to 11 in that a water pressure measuring device 90 is interposed between the flow path switching adapter 40 and the first check valve 50, and the spring water observation is performed while measuring the water pressure in the first flow path and the water pressure in the packer 26 (equal values) using the water pressure measuring device 90.

[0100] As shown in Figure 13A, the water pressure measuring device 90 includes a main channel 92 that forms a first flow path and branch channels 93 that branch off from the main channel 92 inside the main pipe 91, and a counterbore groove 94 is provided on the outer surface of the main pipe 91.

[0101] A second check valve 95 is provided in the middle of the branch channel 93, which includes a spring 96 and a rubber ball 97 that is biased toward the counterbore groove 94 by the spring 96.

[0102] When water is supplied to the packer device 20 in order to inflate the packer 26, as shown in Figure 13A, the second check valve 95 closes the branch passage 93, and thus the liquid-tightness of the first passage, which is composed of the main passage 92, is ensured.

[0103] On the other hand, as shown in Figure 13B, when a check valve 99 equipped with a push-in material 99b at its tip is attached to the counterbore groove 94 in the Z1 direction, the push-in material 99b pushes the rubber ball 97 in the Z2 direction against the biasing force of the spring 96, opening the branch passage 93. This connects the main passage 92, the branch passage 93, and the through hole 99a of the check valve 99, allowing drainage to occur in the Z3 direction from the main passage 92, which constitutes the first passage.

[0104] By attaching a pressure gauge 49 to the check valve 99 mounted on the water pressure measuring device 90, as shown in Figure 12, the water pressure in the first flow path 25 is measured. This leads to the measurement of the water pressure in the packer 26, making it possible to conduct seepage observation while measuring the water pressure in the packer 26. In other words, if the pressure exerted on the borehole wall of the borehole B by the water pressure in the packer 26 is greater than the seepage pressure, the state shown in Figure 12 can be maintained, allowing seepage observation to continue.

[0105] On the other hand, if the pressure exerted on the borehole wall of borehole B by the packer 26's water pressure is less than the seepage pressure, measures can be taken to increase the water pressure of the packer 26 to a level that can withstand the seepage pressure by connecting a water supply means (not shown) to the check valve 99 and supplying additional water to the first channel. In addition, as described above, the moving device 17 of the drilling machine 10 may be reattached to the axial unit 60 to maintain the installation position of the axial unit 60 in borehole B.

[0106] Furthermore, after the spring water observation is completed, as shown in Figure 13B, a check valve 99 is attached to the counterbore groove 94 to open the branch channel 93, allowing drainage through the branch channel 93 and the through-hole 99a of the check valve 99.

[0107] In the illustrated modified version of the groundwater observation method, when inserting the axial unit 60 into the borehole B, the check valve 99, pressure gauge 49, etc., are not attached to the counterbore groove 94 of the water pressure measuring device 90, thereby preventing them from interfering with the centralizers 18A and 18B.

[0108] Although not shown in the diagram, a configuration in which a water pressure measuring device is incorporated into the first check valve, and the two are integrated, may be used as a component of the spring water observation device. With this configuration, it is possible to enjoy the various functions of the water pressure measuring device (water pressure measurement function, additional water supply function, drainage function) while suppressing an increase in the number of parts.

[0109] Furthermore, other embodiments may be used in which other components are combined with the configurations listed in the above embodiments, and the present invention is not limited in any way to the configurations shown herein. In this regard, modifications can be made without departing from the spirit of the present invention, and can be appropriately determined according to the application form. [Explanation of Symbols]

[0110] 10: Drilling machine 11: Trolley 12, 12A, 12B: Boom 13: Man Cage (Workbench) 14: Guide Shell 15: Drifter 16: Shank Rod 17: Mobile device 18A: Forward centralizer (centralizer) 18B: Rear centralizer (centralizer) 20: Packing device 21, 21A, 21B, 21C: Main body tube 21a: Tip 21b: Rear end 21c: Packer mounting opening 21d: Mounting grooves 22: Collection tube 23: Second channel 24: Sealant 25: First channel 26: Packer 30: Double-tube rod 30A: Double-walled rod (extension pipe) 31:Outer tube 31a: Tip 31b: Rear end 32: Inner tube 33: Second channel 34: Sealant 35: First channel 40: Flow path switching adapter 41: Main tube 41a: Tip 41b: Rear end 43: Second channel 43a: Mounting port 44: Sealant 45: First channel 46:Introduction tube 48: Observation instrument 49: Pressure gauge 50: First check valve 51: Main tube 51a: Tip 51b: Rear end 51c: Sealant 52: Alveolar seat 52a:Aperture 52b:Hollow 53: First channel 54: Spring 55: Rubber ball 60: Shaft-shaped unit 70: Push-in tube 80: Irregular-shaped connector 90: Water pressure measuring device 91: Main pipe 92: Main channel 93: Branch flow path 94: Counterbore groove 95: Second check valve 96: Spring 97: Rubber ball 99: Check valve 99a: Through hole 99b: Pressing material 100: Spring water observation device G: Natural ground B: Borehole (advanced borehole) K: Post W: Spring water

Claims

1. A groundwater observation device installed in a borehole at the face of a tunnel, which collects groundwater from the tip of the borehole to perform groundwater observation, A packer device equipped with a packer, a double-tube rod attached to one end of the packer device, a flow path switching adapter attached to one end of the double-tube rod and equipped with an observation meter, and a first check valve attached to one end of the flow path switching adapter, A moving device for inserting at least a portion of a shaft-shaped unit, which is formed by the interconnection of the packer device, the double-pipe rod, the flow path switching adapter, and the first check valve, into the borehole and withdrawing the shaft-shaped unit from the borehole, A first channel is provided inside the axial unit to allow the supplied water to reach the inner surface of the packer, The packer device, the double-tube rod, and the flow path switching adapter are provided with a second flow path that allows the spring water taken in by the packer device to reach the observation meter, A spring water observation device characterized in that the first check valve opens the first channel when supplying water to the packer device and closes the first channel when return water returns from the packer device.

2. A drilling machine comprising a trolley, a boom rotatably mounted on the trolley, a guide shell mounted on the tip of the boom, a drifter that slides along the guide shell, a shank rod mounted on the tip of the drifter, and a water supply means for supplying water to the shank rod, wherein the drifter and the shank rod form the moving device, the axial unit is directly or indirectly connected to the shank rod, and water is supplied from the water supply means to the first channel, as described in claim 1.

3. The spring water observation device according to claim 2, further comprising a non-standard connector interposed between the shank rod and the first check valve.

4. A front centralizer and a rear centralizer are mounted at the tip and rear of the aforementioned guide shell, respectively. The system further includes a push-in pipe interposed between the aforementioned irregularly shaped connector and the first check valve, The groundwater observation device according to claim 3, characterized in that the first check valve is located on the face side of the forward centralizer.

5. A water pressure measuring device is interposed between the flow path switching adapter and the first check valve to measure the water pressure in the first flow path. The water pressure measuring device comprises a main channel forming the first channel and branch channels branching off from the main channel. A counterbore groove is provided on the outer surface of the aforementioned water pressure measuring device. A second check valve is interposed in the middle of the aforementioned branch channel, and the second check valve closes the branch channel when water is supplied to the packer device. The spring water observation device according to claim 1 or 2, characterized in that a check valve is installed in the counterbore groove and the water pressure in the first flow path is measured.

6. The spring water observation device according to claim 5, characterized in that the check valve is attached to the water pressure measuring device so that at least one of additional water supply to the first channel or drainage from the first channel is further performed.

7. The spring water observation device according to claim 5, characterized in that the first check valve and the water pressure measuring device are integrally configured, and the branch flow path is provided on the flow path switching adapter side of the first check valve.

8. A method for observing groundwater by collecting groundwater from the tip of a borehole installed at the tunnel face, The apparatus installation process involves: an axial unit comprising a packer device equipped with a packer, a double-tube rod, a flow path switching adapter equipped with an observation meter, and a first check valve, all interconnected; a first flow path that allows water supplied inside the axial unit to reach the inner surface of the packer; and a second flow path that allows groundwater taken in by the packer device to reach the observation meter, wherein at least a portion of the axial unit is inserted into the borehole using a moving device; the packer device is positioned at or near the tip of the borehole; and the packer is expanded laterally by water supplied through the first flow path, thereby pressing the packer against the borehole wall; An observation process in which seepage water is taken in from the tip of the borehole via the second channel and brought to the observation instrument, and seepage water observation is performed, A method for observing groundwater, characterized by comprising a device retrieval step of draining the packer by draining it through the first channel and using the moving device to pull out and retrieve the axial unit from the borehole.

9. In the aforementioned device installation process, A drilling machine comprising a trolley, a boom rotatably mounted on the trolley, a guide shell mounted on the tip of the boom, a drifter that slides along the guide shell, a shank rod mounted on the tip of the drifter, and a water supply means for supplying water to the shank rod, The guide shell, the drifter, and the shank rod form the moving device, and the axial unit is directly or indirectly connected to the shank rod. The method for observing groundwater seepage according to claim 8, characterized in that the drifter is advanced toward the face to push in the packer device and the double-tube rod, the drifter is retracted to add a new double-tube rod, and the drifter is advanced toward the face again.

Images