JP4689702B2 - Water level recovery observation device - Google Patents

Description

  The present invention relates to a water level recovery observation apparatus, and more particularly, a water level recovery observation that shortens the time required for an on-site hydraulic test and can effectively observe water level recovery even for a low permeability medium. Relates to the device.

At present, in-situ hydraulic tests for knowing the hydraulic characteristics of the medium in the borehole can be roughly divided into pumping tests, instantaneous impact tests, and constant pressure injection tests.
Among them, the pumping test and the instantaneous impact test will observe the water level recovery characteristics in the medium, and in order to investigate the more accurate hydraulic characteristics especially in the crystalline rock, it is necessary to isolate the section of interest that is not in the bare hole state. There is.

  Thus, in order to observe the water level recovery characteristic through the medium in the region of interest, the water level recovery observation device is used.

A configuration of a conventional general water level recovery observation apparatus will be described with reference to FIGS. 1 and 2.
Here, FIG. 1 is a configuration diagram illustrating a state before the packer is expanded in the conventional groundwater sampling apparatus.
FIG. 2 is a configuration diagram illustrating a state in which the packer is inflated by the expansion fluid and is in close contact with the inner surface of the borehole in the conventional groundwater sampling apparatus.

  The conventional groundwater sampling device includes an upper packer 10 and a lower packer 30 provided at the upper and lower parts, supply pipes 20 and 40 for supplying an expansion fluid to the packer and applying fluid pressure, and a connecting pipe for connecting the packers 10 and 30. 60 and a guide pipe 50 for guiding the groundwater W existing in the sampling space between the packers 10 and 30 to the outside of the borehole H.

  Here, as shown in FIG. 2, a pair of packers are supplied with fluid via supply pipes 20 and 40, and are in close contact with the inner surface of the borehole H while expanding outward, and the packer 10 is placed in the borehole H. , 30 regions of interest are hydraulically isolated.

  The supply pipes 20 and 40 include an upper supply pipe 20 that supplies an expansion fluid to the upper packer 10 and a lower supply pipe 40 that communicates with the upper supply pipe 20 and supplies an expansion fluid to the lower packer 30. .

Therefore, if the expansion fluid is supplied to the upper packer 10 through the upper supply pipe 20, the expansion fluid also flows in the lower supply pipe 40 communicating with the upper packer 10, and the expansion fluid is supplied to the lower packer 30. .
That is, by supplying an expansion fluid to the upper supply pipe 20, the upper and lower packers 30 are expanded at the same time and are brought into close contact with the inner surface of the borehole H.

On the other hand, the connection pipe 60 is formed with an inflow hole 62 through which the groundwater W existing in the collection space isolated by the packers 10 and 30 flows.
In addition, the connecting pipe 60 that connects the packers 10 and 30 has a plurality of segments connected to each other in an assembly manner, and maintains the interval between the packers 10 and 30.
Therefore, the groundwater W in the desired depth section in the borehole H can be collected by adjusting the number of segments of the connecting pipe 60 that connects the packers 10 and 30.

  Next, a process of observing water level recovery in the borehole using the water level recovery observation apparatus having the above-described configuration will be described with reference to FIGS. 3 and 4.

  Here, FIG. 3 is a block diagram showing a state where the groundwater level is the reference water level in the water level recovery observation apparatus of FIG. FIG. 4 is a configuration diagram showing a state in which the groundwater level is lowered to the changed water level in the water level recovery observation apparatus of FIG.

  When the groundwater level in the connecting pipe is the reference water level as shown in FIG. 3 and the groundwater level is lowered to the changing water level as shown in FIG. 4, the upper packer and the lower part are connected via the inner wall of the borehole. While groundwater flows into the space between the packer, the groundwater level in the connecting pipe is restored to the reference water level again.

  In addition, the water level recovery characteristics are analyzed and a hydraulic test is performed.

  However, in the conventional water level recovery observation device, when the periphery of the borehole is a highly permeable medium, the water level recovery can proceed rapidly and the hydraulic test can be performed smoothly, but the water permeability is lower. In the case of a medium, the head recovery time is remarkably delayed, and a considerable time is required until the head returns to the reference water level.

  In other words, if the medium around the borehole has a low water permeability and the amount of groundwater inflow is very small, it takes a very long time for the groundwater level to recover to the reference water level, thus completing the on-site hydraulic test. There was a limit to having to consume a lot of time.

  The present invention has been devised in order to solve the above-described conventional problems, and an object thereof is to provide a water level recovery observation apparatus that shortens the time required for an on-site hydraulic test.

  Another object of the present invention is to provide a water level recovery observation device that can effectively observe water level recovery regardless of the water permeability of the medium.

  In order to achieve the above-mentioned object, the present invention is a water level recovery observation device for observing water level recovery of a fluid inserted in a borehole and selected on the inner surface of the borehole. A first packer that closely contacts, a supply pipe that supplies an expansion fluid to the inside of the first packer, and a sampling space below the first packer, and the fluid that exists in the sampling space passes through the borehole And a guide tube that has a smaller cross-sectional area than the guide tube, communicates with the guide tube, and provides a flow path through which the fluid existing in the sampling space flows. Provide a water level recovery observation device.

  The observation tube is preferably connected to a lower portion of the guide tube. At the same time, a valve portion for selectively blocking the flow path is provided inside the guide tube, and it is preferable that the groundwater level flows into the observation tube when the water level is restored.

  On the other hand, the water level recovery observation apparatus according to the present invention preferably includes a water level measuring device for observing at least one of the guide tube and the observation tube.

  Moreover, it is preferable that the water level recovery observation apparatus according to the present invention further includes a second packer that is provided at a lower portion than the first packer and is selectively in close contact with the inner surface of the borehole.

  In addition, the water level recovery observation device includes a connection pipe that is provided between the first packer and the second packer and connects the packer, and the connection pipe is isolated by the first packer and the second packer. An inflow hole for flowing in groundwater existing in the collected space can be formed.

  The water level recovery observation apparatus according to the present invention having the above-described configuration has the following effects.

  First, by providing a guide tube and a separate observation tube having a small diameter, there is an advantage that the time required to recover the groundwater level can be shortened and the water level recovery characteristics can be observed quickly.

  That is, when the groundwater level recovers, the guide pipe is shut off and the water level is recovered through the observation tube having a small diameter, so that rapid water level recovery can be observed.

  For example, when the inner diameter of the guide tube is 25 mm and the inner diameter of the observation tube is 2.5 mm, by using the observation tube as compared with the conventional method of observing the water level recovery through the guide tube, The required time can be reduced to 1/100 times.

  Second, there is an advantage that a smooth hydraulic test is possible regardless of the medium characteristics around the borehole.

  Specifically, the time required for observing the water level recovery because the water level recovers quickly through the observation tube even under conditions where the water level recovery is extremely slow due to the small amount of groundwater inflow in a low permeability medium. As a result, the hydraulic test can be performed smoothly.

  Hereinafter, preferred embodiments of the present invention in which the objects of the present invention are specifically realized will be described with reference to the accompanying drawings. In the drawings describing the present embodiment, the same reference numerals denote the same members. Further, an additional description relating to this will be omitted.

  The configuration of a water level recovery observation apparatus according to an embodiment of the present invention will be described with reference to FIG.

  The water level recovery observation device according to the present embodiment is a device that is inserted into the borehole H and collects the fluid existing in the borehole H, and includes a pair of packers 110 and 130, a connecting pipe 160, Supply pipes 120 and 140, a guide pipe 150, and an observation pipe 170 are provided.

  Here, it can be said that the object of the collection device according to the present embodiment is various fluids. Below, groundwater W which exists in the borehole H is illustrated and demonstrated as an example of the fluid used as extraction object.

  The packers 110 and 130 are configured to include a first packer 110 and a second packer 130, each of which receives supply of an expansion fluid from the outside and selectively adheres to the inner surface of the borehole H while increasing the volume.

  The connecting pipe 160 is provided between the packers 110 and 130 and interconnects the packers 110 and 130. In addition, the connection pipe 160 is formed with an inflow hole 162 through which the groundwater W existing in the collection space isolated by the packers 110 and 130 flows.

  In addition, the connecting pipe 160 that connects between the packers 110 and 130 has a plurality of segments connected to each other in an assembling manner, and maintains an interval between the packers 110 and 130. Therefore, by adjusting the number of segments of the connecting pipe 160 that connects the packers 110 and 130, the groundwater W in the desired depth section in the borehole H can be collected.

  The supply pipes 120 and 140 supply the expansion fluid into the pair of packers, supply the expansion fluid to the first packer 110, and the lower supply pipe 140 supply the expansion fluid to the second packer 130. Is provided.

  The guide tube 150 communicates with the sampling space hydraulically separated by the expansion of the first packer 110 and the second packer 130 and extends outside the borehole H, and guides the fluid existing in the sampling space to the outside. .

  The observation tube 170 is configured to communicate with the guide tube 150, and a flow path through which a fluid existing in the collection space can flow is formed.

  The observation tube 170 is configured separately from the guide tube 150, is connected to the connection tube, and has a smaller cross-sectional area than the guide tube 150.

  The position where the observation tube 170 is connected to the connection tube 160 is not limited, but is preferably connected to the lower portion of the guide tube 150 in order to more effectively observe the water level recovery.

  In the present invention, since the observation pipe 170 having a small diameter is provided separately from the guide pipe 150, the water level is restored from the changed water level to the reference water level by the observation pipe 170 having a small diameter. It can be observed more quickly.

  In particular, the water level is quickly recovered by the observation tube 170 even under conditions where the water level recovery is extremely slow in a low water permeability medium, so that the time required to observe the water level recovery is shortened, resulting in a hydraulic test. To make it smooth.

  On the other hand, it is preferable that a valve unit 180 for selectively blocking the flow path is provided inside the guide tube 150.

  If the water level is changed by using the guide pipe 150 and the water level recovers, the water level is recovered by the observation pipe 170 having a small diameter if the valve unit 180 is closed and the lower part of the guide pipe 150 is shut off. become.

  FIG. 5 schematically shows a form in which the flow path is opened and closed by two members that move in the lateral direction, but various known methods can be adopted as a specific form of the valve unit 180.

  FIG. 6 is a modification of FIG. 5, and the basic components are the same as those of the above-described embodiment. However, in this modification, there is a difference in the specific configuration of the valve unit 280.

  In this modification, a stopper 282 is formed inside the guide tube 150, and an O-ring 284 inserted into the guide tube 150 is fixed to the stopper 282, and the flow path blocking ball 286 is again formed from the ground. The flow path of the guide pipe 150 is blocked and the groundwater is prevented from flowing into the guide pipe 150.

  In this modification, a method of blocking the flow path using the spherical flow path blocking sphere 286 is illustrated, but unlike this, a flow path blocking member having an inverted conical shape is dropped on the guide tube 150 to flow. Various methods such as a method for blocking a road can be applied.

  On the other hand, in this embodiment, an automatic water level measuring device 190 is provided so that the water level of the guide tube 150 and the observation tube 170 can be measured.

  The operation process of the water level recovery observation apparatus having the above-described configuration will be described as follows.

  First, the expansion fluid is supplied to the first packer 110 and the second packer 130 through the upper supply pipe 120 and the lower supply pipe 140.

  The packers 110 and 130 receive the supply of the expansion fluid and expand in volume, closely contact the inner surface of the borehole H, and hydraulically isolate the space between the packers 110 and 130.

  Thereafter, the water level is changed through the guide pipe 150, and when the water level recovers, the valve portions 180 and 280 are closed to block the lower part of the guide pipe 150.

  As a result, the groundwater level is recovered by an observation tube having a diameter smaller than that of the guide tube 150, and the hydraulic test is executed by grasping the water level recovery characteristic by the water level measuring device.

  In the embodiment described above, the packer is paired and the water level recovery is observed in the section of interest isolated by the packer. However, unlike the above, the packer is composed of a single packer, and the lower part of the packer is observed. It can also be configured to observe water level recovery in the region.

  As described above, the preferred embodiments of the present invention have been described with reference to the preferred embodiments of the present invention. However, those skilled in the relevant arts should not depart from the spirit and scope of the present invention described in the claims. Thus, it will be understood that the present invention can be variously modified and changed. In other words, the technical scope of the present invention is defined based on the claims, and is not limited by the best mode for carrying out the invention.

It is a block diagram which shows the conventional water level recovery observation apparatus. It is a block diagram which shows the form which the packer expanded by the water level recovery observation apparatus of FIG. 1 and closely_contact | adhered to the borehole inner surface. It is a block diagram which shows the state whose groundwater level is a reference | standard water level with the water level recovery observation apparatus of FIG. It is a block diagram which shows the state which the groundwater level fell to the change water level with the water level recovery observation apparatus of FIG. It is a block diagram which shows the water level recovery observation apparatus which concerns on one Embodiment of this invention. It is sectional drawing which shows the modification of the valve | bulb part of FIG.

Explanation of symbols

110: Upper packer 120: Upper supply pipe 130: Lower packer 140: Lower supply pipe 150: Guide pipe 160: Connection pipe 180: Valve section 190: Water level measuring device A: Reference water level B: Change water level H: Borehole W: Groundwater

Claims (7)

A water level recovery observation device for observing water level recovery of fluid in the borehole inserted into the borehole,
A first packer that selectively adheres to the inner surface of the borehole;
A supply pipe for supplying an expansion fluid into the first packer;
A guide tube that communicates with the sampling space below the first packer and guides the fluid present in the sampling space to the outside of the borehole;
An observation tube that has a smaller cross-sectional area than the guide tube, communicates with the guide tube, and provides a flow path through which the fluid existing in the collection space flows;
A water level recovery observation device characterized by comprising: The observation tube is
The water level recovery observation device according to claim 1, wherein the water level recovery observation device is connected to a lower portion of the guide tube. Inside the guide tube,
The water level recovery observation apparatus according to claim 1, further comprising a valve unit that selectively blocks the flow path.   The water level recovery observation apparatus according to claim 1, further comprising a water level measuring device for observing at least one of the guide tube and the observation tube.   The hydraulic test apparatus according to claim 1, further comprising a second packer that is provided at a lower portion than the first packer at a predetermined interval and that selectively adheres to the inner surface of the borehole.   The water level recovery observation apparatus according to claim 5, further comprising a connecting pipe provided between the first packer and the second packer and connecting the packer.   7. The water level recovery observation apparatus according to claim 6, wherein an inflow hole is formed in the connection pipe for flowing in groundwater existing in a sampling space separated by the first packer and the second packer. .

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