Spring water observation equipment and spring water observation methods

Abstract

To provide a spring water observation system and a spring water observation method which can unnecessitate setting and recovery of a packer done by man power to / from a borehole enabling safe and efficient grasping of the conditions of the spring water at the forward point of a working face.SOLUTION: A spring water observation system 100 is set in a borehole B arranged at a working face K to perform spring water observation by taking spring water W from the borehole B, comprising: a flow-path-changing adapter 40 that includes a packer device 20, a double-tubing rod 30 and an observation meter 48; a water-pressure-measuring device 90; a first check valve 50; a shifting device 17 that pulls out a shaft-like unit 60 that is formed with these aforesaid items; a first flow path to make the conveyed water reach the inner side face of a packer 26; and a second flow path to make the spring water W that was taken in with the packer device 20 reach the observation meter 48. The water-pressure-measuring device 90 at least measures the water pressure inside the first flow path. The first check valve 50 opens the first flow path 53 when water is conveyed to the packer device 20, and closes the first flow path 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 spring water observation device and a spring water observation method. [Background Art]

[0002] In the construction of mountain tunnels, it is essential to grasp the spring water conditions such as the spring water volume and spring water pressure in the spring water section ahead of the tunnel face, and take countermeasures against spring water in advance. As a method for grasping this spring water condition, it is generally practiced to drill a borehole (advanced borehole) at the tunnel face, manually insert the packer deep into the hole while connecting rods equipped with a packer (packer rods), measure the spring water volume and spring water pressure, and then manually pull out and recover the packer rods. However, with this method, there is a safety issue because workers have to enter the area directly below the tunnel face. In addition, under the situation where spring water is drained from the borehole, the work of inserting and pulling out the packer requires a lot of labor. In particular, for boreholes located at high places such as near the crown of the tunnel face, the work has to be carried out on the cage of the drilling machine or the bucket of an aerial work platform, which can make the work even more difficult. In addition, when the spring water pressure is high, there is a risk that the packer will eject from the borehole, so packer pressing equipment or the like is required to prevent the packer from ejecting, which takes labor and time to grasp the spring water condition.

[0003] Based on the above, there is a need for a spring water observation device and a spring water observation method that eliminate the need for manual installation and recovery of the packer in the borehole, and can safely and efficiently grasp the spring water conditions (spring water volume, spring water pressure, water quality, etc.) ahead of the tunnel face.

[0004] Here, Patent Document 1 proposes a double-tube double packer method that performs excavation and grouting using a drill jumbo and a packer. 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 Initiative] [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 water pressure measuring device is interposed between the flow path switching adapter and the first check valve, 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, the water pressure measuring device, 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 water pressure measuring device measures at least the water pressure in the first flow path, The first check valve is configured to open the first passage when supplying water to the packer device and to close the first passage when return water returns from the packer device. The water pressure measuring device comprises a main channel forming the first channel and branch channels branching off from the main channel. 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. A check valve is installed in the branch channel, and the water pressure in the first channel is measured.

[0009] According to this embodiment, a moving device is provided to insert at least a part of an axial unit, which is made up of a packer device, a double-pipe rod, a flow path switching adapter equipped with an observation meter, a water pressure measuring device, 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. Furthermore, by interposing a water pressure measuring device between the flow path switching adapter and the first check valve, it is possible to measure 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 to confirm whether the packer is being maintained at the desired water pressure (pressure on the wall). 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. This ensures the liquid-tightness of the first channel when water is supplied to the packer device.

[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.

[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. Furthermore, the phrase "the axial unit is directly or indirectly connected to the shank rod" includes not only the direct connection of the first check valve forming the axial unit to the shank rod, but also the connection of a push-in pipe or irregular connector connected to the first check valve to the shank rod, and thus the indirect connection of the axial unit to the shank rod.

[0014] If the gushing water pressure is relatively low and the installation state of the shaft-like unit in the borehole can be maintained only by the pressing force of the packer against the hole wall of the borehole, 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 boreholes). On the other hand, if the gushing water pressure is relatively high and the installation state of the shaft-like unit in the borehole cannot be maintained only by the pressing force of the packer against the hole wall of the borehole, it is preferable to keep the drilling machine standby in front of the working face until the gushing water observation is completed, and hold the shaft-like unit from the rear by the drifter and the shank rod.

[0015] In another aspect of the gushing water observation device according to the present invention, On the outer surface of the water pressure measurement device, a recess is provided at a position corresponding to the branch flow path, and an opening of the branch flow path faces the recess, The height of the check valve when attached to the opening is set to be equal to or less than the depth of the recess, The check valve is attached to the water pressure measurement device, so that at least one of additional water supply to the first flow path or drainage from the first flow path is further performed.

[0016] According to this aspect, a recess is provided at a position corresponding to the branch flow path on the outer surface of the water pressure measurement device, an opening of the branch flow path faces the recess, and the height (protrusion height) of the check valve when attached to the opening is set to be equal to or less than the depth of the recess. Thereby, when inserting the shaft-like unit into the borehole, the check valve attached to the opening can pass through the centralizer without interfering with the centralizer.

[0017] In addition, a check valve is attached to the water pressure measurement device, and a pressure gauge is attached to the check valve to measure the water pressure in the first flow path. Furthermore, by additionally performing additional water supply to the first flow path or drainage from the first flow path, the water pressure measurement device can be provided with various functions. For example, if the water pressure required for the packer is insufficient as a result of measuring the water pressure in the first flow path, a water supply means can be connected to the check valve, and additional water can be supplied to the first flow path to increase the water pressure in the packer. Furthermore, after the spring water observation is completed, when draining water to deflate the packer and recovering the packer device or the like from the borehole, opening the second check valve provided inside the check valve installed in the recess enables drainage through the branch flow path and the check valve.

[0018] Another aspect of the spring water observation device according to the present invention is characterized in that: said first check valve and said water pressure measuring device are integrally configured, and said branch flow path is provided closer to said flow path switching adapter side than said first check valve.

[0019] According to this aspect, since the first check valve and the water pressure measuring device are integrally configured, it is preferable because various functions of the water pressure measuring device can be obtained while reducing the number of parts.

[0020] Another aspect of the spring water observation device according to the present invention is characterized in that: the device further comprises a profile connector interposed between said shank rod and said first check valve.

[0021] According to this aspect, since a profile connector (or a diameter conversion connector) is interposed between the shank rod of the drilling machine and the first check valve, the first check valve can be connected in accordance with the diameter of the shank rod specific to the model of the drilling machine.

[0022] In another aspect of the spring water observation device according to the present invention, a front centralizer and a rear centralizer are respectively attached to the tip of said guide shell and to the rear of said tip, the device further comprises a push-in pipe interposed between said profile connector and said first check valve, said first check valve is located closer to the face side than said front centralizer.

[0023] According to this embodiment, by interposing a push pipe between the irregularly shaped connector and the first check valve, the first check valve and the flow path switching adapter can be positioned in front of the forward centralizer in the guide shell. By positioning these first check valve and flow path switching adapter near the face, in other words, by installing the axial unit in the borehole without long members protruding from the face, interference with other face operations can be suppressed.

[0024] In this context, the guide shell of a drilling machine is generally equipped with two centralizers (a front centralizer and a rear centralizer) with hydraulic clamps. These centralizers have the function of centering the drilling rod and the function of gripping the drilling rod with the hydraulic clamps provided by the centralizers.

[0025] In this embodiment, when gripping the axial unit using these two centralizers and inserting it into the borehole while centering it, the use of a push pipe such as a steel pipe makes it possible to position the first check valve and flow path switching adapter located behind the axial unit closer to the drilling face than the front centralizer.

[0026] 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, An apparatus installation step comprising: 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, a water pressure measuring device, and a first check valve connected to each other; 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 inflated by water supplied through the first flow path to press the packer against the borehole wall; A first channel observation step involves observing the first channel using the water pressure measuring device, A spring water observation process is performed, in which spring water is taken in from the tip of the borehole via the second channel and brought to the observation instrument, and spring water observation is performed. The device is characterized by comprising a device retrieval step, in which the packer is deflated by draining water through the first channel, and the shaft-shaped unit is pulled out of the borehole and recovered using the moving device.

[0027] 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, a water pressure measuring device, and a first check valve connected to each other, is inserted into the borehole using a moving device. After inflating the packer 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 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.

[0028] Furthermore, by measuring the water pressure in the first channel and the water pressure in the packer connected to the first channel using the water pressure measuring device, it is possible to confirm whether the packer is being maintained at the desired water pressure.

[0029] 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.

[0030] 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]

[0031] 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]

[0032] [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 5A] This is a magnified view of a check valve. [Figure 5B] This is a magnified view showing a check valve with a socket and flow release valve attached. [Figure 6] This 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] Following Figure 11 is a process diagram of an example of a spring water observation method according to the embodiment. [Modes for carrying out the invention]

[0033] 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.

[0034] [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 5. 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. Furthermore, 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, showing a cross-sectional view of the arrangement of the first flow path and the second flow path in the flow path switching adapter.Furthermore, Figure 5A is an enlarged view of the check valve, and Figure 5B is an enlarged view of the check valve with a socket and a flow path opening valve attached.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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 or short-length boreholes, and are particularly desirable for use in spring water observation using short-length boreholes. Currently, the only method for measuring spring water pressure using short-length boreholes is to manually install a packer device, and as already explained, there is room for improvement in terms of safety and efficiency in observation construction. Therefore, the spring water observation device and spring water observation method according to the embodiment described below can be a technology that enhances construction safety and construction efficiency in spring water observation construction using short-length boreholes.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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, a water pressure measuring device 90 attached to the rear end of the flow path switching adapter 40, and a first check valve 50 attached to the rear end of the water pressure measuring device 90. 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.

[0047] In this illustrated example, the water pressure measuring device 90 and the first check valve 50 are separate components, but for example, the water pressure measuring device and the first check valve may be integrated and both be the same component.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] Water supplied to the shaft-shaped unit 60 via the water supply means equipped on the trolley 11 inflates the packer 26 of the packer device 20, pressing against the borehole wall, thereby completing the installation of the shaft-shaped unit 60 into the borehole.

[0052] 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.

[0053] The pressure exerted by the packer device 20 against the borehole wall is measured by a pressure gauge attached to the water pressure measuring device 90. If the measured data is lower than a predetermined water pressure, additional water can be supplied via the water pressure measuring device 90 to further inflate the packer 26 and increase the water pressure to the predetermined water pressure (pressure against the wall). Furthermore, when the groundwater observation is completed and a portion of the axial unit 60 is withdrawn and recovered from the borehole, the packer 26 can be deflated by draining water from the packer device 20 via the water pressure measuring device 90.

[0054] In other words, the water pressure measuring device 90 has multiple functions, including measuring the pressure (water pressure) applied to the wall by the packer 26, supplying additional water to the packer 26 as needed, and draining the water that is inflating the packer 26 when the axial unit 60 is pulled out and recovered.

[0055] Furthermore, by inserting the push 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, the water pressure measuring device 90, 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 pipe 70 and the irregular connector 80 can be disconnected, and the drilling machine 10 can be used for other purposes.

[0056] Here, a recess 94 is provided on the outer surface of the water pressure measuring device 90, and a check valve 96 is attached to the recess 94. The check valve 96 does not protrude outward beyond the recess 94, and therefore, even with the check valve 96 attached to the recess 94, the check valve 96 can also be inserted through the front centralizer 18A and the rear centralizer 18B.

[0057] In the illustrated 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.

[0058] Next, with reference to Figures 3 to 5, the specific configurations of each component constituting the axial unit 60 will be described.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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 expand in the Y7 direction. The laterally expanded 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.

[0063] The tip 31a of the outer tube 31 that constitutes the double-tube rod 30 is fitted into the rear end 21b of the main tube 21B.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] Meanwhile, the water supplied from the water pressure measuring device 90 flows into multiple first flow channels 45 in the main pipe 41, circulates 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.

[0074] The tip 91a of the main pipe 91 that constitutes the water pressure measuring device 90 is fitted into the rear end 41b of the flow path switching adapter 40.

[0075] The water pressure measuring device 90 has a main pipe 91. A sealing material 95 made of an O-ring is provided at the tip end of the main pipe 91, and the rear end 41b of the flow path switching adapter 40 is fitted onto the tip 91a of the main pipe 91, and the two are connected while sliding contact is made with the sealing material 95.

[0076] The water pressure measuring device 90 includes a main channel 92 that forms a first channel and branch channels 93 that branch off from the main channel 92 inside the main pipe 91. A recess 94 is provided on the outer surface of the main pipe 91 at a position corresponding to the branch channel 93, and the opening 93a of the branch channel 93 faces the recess 94.

[0077] As shown in Figure 3, a check valve 96 is installed in the opening 93a. Here, the depth of the recess 94 is t1, and the height t2 of the check valve 96 is set to be less than or equal to the depth t1. As a result, when inserting the shaft unit 60 into the borehole B, even with the check valve 96 installed in the opening 93a, the check valve 96 can be inserted without interfering with the centralizers 18A and 18B.

[0078] As shown in Figure 5A, the check valve 96 attached to the opening 93a of the branch passage 93 includes a second check valve 96c that is normally biased by a spring 96e in a direction that closes the passage 96b (upward in the illustrated example) through the passage 96b that passes through the valve body 96a. A sealing material 96d made of an O-ring is attached to the outer circumference of the second check valve 96c, and the passage 96b is closed when the sealing material 96d comes into contact with the wall surface of the passage 96b.

[0079] When the water pressure measuring device 90 does not measure the water pressure (pressure on the wall) inside the packer 26, does not supply additional water to the packer 26, or drain water from the packer 26, but instead inflates the packer 26 by supplying water from a water supply means (not shown), the branch passage 93 is closed by the check valve 96, thereby ensuring the liquid-tightness of the first passage, which is composed of the main passage 92, and allowing water to be supplied to the packer 26 in the Y3 direction.

[0080] On the other hand, when measuring the water pressure inside the packer 26, supplying additional water to the packer 26, or draining water from the packer 26, as shown in Figure 5B, a socket 97 is fitted onto the check valve 96, and a flow path release valve 98 is attached to the socket 97. This releases the blockage of the flow path 96b of the check valve 96 by the sealing material 96d, thereby creating a water flow in the Y16 direction.

[0081] More specifically, a push pin 98a is attached to the tip of the flow path release valve 98. When the flow path release valve 98 is attached to the socket 97, the push pin 98a pushes the second check valve 96c, which is biased by the spring 96e, in the Z1 direction against the biasing force of the spring 96e. This causes the second check valve 96c to move toward the main flow path 92 in the Z2 direction, opening the flow path 96b of the check valve 96. As a result, the main flow path 92, the flow path 96b of the check valve 96, the inside of the socket 97, and the inside of the flow path release valve 98 are in fluid communication with each other.

[0082] When measuring the water pressure inside the packer 26, a pressure gauge (not shown) is attached to the flow path release valve 98. When supplying additional water to the packer 26, additional water is supplied via the flow path release valve 98 from a water supply means (not shown). Furthermore, when draining water from the packer 26, the water flowing through the main flow path 92 is drained in the Y16 direction via the flow path release valve 98.

[0083] The rear end 91b of the water pressure measuring device 90 is fitted with the tip 51a of the main pipe 51 that constitutes the first check valve 50.

[0084] 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.

[0085] A sealing material 51c, which is an O-ring, is provided at the tip end of the main pipe 51, and the rear end 91b of the water pressure measuring device 90 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.

[0086] 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.

[0087] 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. Through the opening 52a, the water flows through the first channel 53 on the water pressure measuring device 90 side in the Y2 direction and into the first channel 92 of the water pressure measuring device 90.

[0088] 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.

[0089] By closing this opening 52a, the return water in the Y17 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.

[0090] 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.

[0091] 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.

[0092] 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.

[0093] [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 6 to 12. Here, Figures 6 to 12 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.

[0094] First, as shown in Figure 6, 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.

[0095] 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.

[0096] 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.

[0097] Next, as shown in Figure 7, 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.

[0098] 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 7.

[0099] 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.

[0100] 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).

[0101] As shown in Figure 7, 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.

[0102] Therefore, as shown in Figure 8, the connection between the flow path switching adapter 40 and the irregular connector 80 is released. First, the water pressure measuring device 90 is connected to the flow path switching adapter 40, the first check valve 50 is connected to the water pressure measuring device 90, and the push-in pipe 70 is connected to both the first check valve 50 and the irregular connector 80.

[0103] 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, a water pressure measuring device 90, 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.

[0104] As shown in Figure 8, 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 inflated in the Y7 direction by water supplied from a water supply means (not shown). The inflated packer 26 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.

[0105] As already explained with reference to Figure 3, a check valve 96 with an overhang length less than or equal to the depth of the recess 94 is installed in the recess 94 on the outer circumference of the water pressure measuring device 90. As a result, when the shaft unit 60 is inserted into the borehole B, the check valve 96 is inserted without interfering with the centralizers 18A and 18B.

[0106] Next, as shown in Figure 9, 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.

[0107] 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.

[0108] 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).

[0109] After the device is installed, as shown in Figure 9, a socket 97 is attached to the check valve 96 attached to the water pressure measuring device 90, a flow path release valve 98 is attached to the socket 97, and a pressure gauge 49 is attached to the flow path release valve 98. The pressure gauge 49 is used to observe the pressure in the first flow path and the pressure inside the packer 26 (pressure force pressing against the wall) which is the same value (first flow path observation step). This first flow path observation step may be carried out continuously during the spring water observation step described below, or it may be carried out intermittently at intervals.

[0110] During the groundwater observation process, if the measured data (pressure force by the packer 26) falls below a predetermined water pressure (pressure force that can hold the axial unit 60 within the borehole wall of borehole B), additional water can be supplied via the water pressure measuring device 90 to further inflate the packer 26 and raise the water pressure to the predetermined level, thereby maintaining the installation position of the axial unit 60 relative to the borehole wall of borehole B.

[0111] Next, as shown in Figure 10, 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.

[0112] 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 (this completes the groundwater observation process).

[0113] After the spring water observation is completed, as shown in Figure 11, the drilling machine 10 is brought close, the irregular connector 80 is connected to the push pipe 70, and the water that had been inflating the packer 26 is drained in the Y17 direction through the flow path release valve 98 attached to the water pressure measuring device 90, thereby deflating the packer 26 in the Y8 direction.

[0114] Next, as shown in Figure 12, 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).

[0115] 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.

[0116] 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]

[0117] 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 91a: Tip 91b: Rear end 92: Main channel (first channel) 93: Branch flow path 93a:Aperture 94: Recess 95: Sealant 96: Check valve 96a: Valve body 96b: Flow channel 96c: Second check valve 96d: Sealant 96e: Spring 97: Socket 98: Flow channel release valve 98a: Push pin 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 water pressure measuring device is interposed between the flow path switching adapter and the first check valve, 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, the water pressure measuring device, 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 water pressure measuring device measures at least the water pressure in the first flow path, The first check valve is configured to open the first passage when supplying water to the packer device and to close the first passage when return water returns from the packer device. The water pressure measuring device comprises a main channel forming the first channel and branch channels branching off from the main channel. 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. A spring water observation device characterized in that a check valve is installed in the branch channel and the water pressure in the first channel is measured.

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 guide shell, 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. A recess is provided on the outer surface of the water pressure measuring device at a position corresponding to the branch channel, and the opening of the branch channel faces the recess. When the check valve is installed in the opening, its height is set to be less than or equal to the depth of the recess. The spring water observation device according to claim 1 or 2, 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 flow path or drainage from the first flow path is further performed.

4. The spring water observation device according to claim 1 or 2, 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.

5. 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.

6. 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 5, characterized in that the first check valve is located on the face side of the forward centralizer.

7. 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, a water pressure measuring device, 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 inflated by water supplied through the first flow path, thereby pressing the packer against the borehole wall; A first channel observation step involves observing the first channel using the water pressure measuring device, A spring water observation process is performed, in which spring water is taken in from the tip of the borehole via the second channel and brought to the observation instrument, and spring 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.

8. 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 for observing groundwater seepage according to claim 7, 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.

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