JP6805040B2 - In-situ test equipment, groundwater level measurement method and soil sample collection method - Google Patents

Description

The present invention relates to an in-situ test device for measuring the groundwater level and collecting a soil sample, and a method for measuring the groundwater level and a method for collecting a soil sample using the same.

Whether or not there is a possibility of liquefaction of the ground during an earthquake is determined based on various ground information at the in-situ, but generally, as disclosed in Patent Documents 1 and 2, standard penetration The results of the test and the Swedish sounding test are used.

Here, in order to determine the ground that is easily liquefied, information on the height of the groundwater level, such as whether or not it is deeper than the groundwater level, is important in addition to the soil quality determination such as whether or not the ground is sandy.

On the other hand, in order to collect the ground below the groundwater level as a soil sample for soil quality determination, as disclosed in Patent Documents 2 and 3, the soil was collected using a sampling device provided with an openable lid. It is necessary to prevent the soil sample from leaking out.

Japanese Patent No. 5526290 Japanese Unexamined Patent Publication No. 2014-77231 Japanese Unexamined Patent Publication No. 2-130499

However, Patent Documents 1-3 mainly disclose a method of sampling for determining liquefaction at the in-situ of the ground, and do not disclose a method of accurately measuring the groundwater level. ..

Further, since the lid disclosed in Patent Documents 2 and 3 is opened and closed by using a rod arranged for the lid, the diameter must be large so that the lid can be operated without being deformed by resistance such as earth pressure. In addition to being large-scale, such as becoming thicker, the production cost is high. In addition, the complexity of the structure makes it more susceptible to damage.

Therefore, the present invention provides an in-situ test apparatus capable of accurately measuring the groundwater level and reliably collecting a soil sample at a desired position with a simple configuration, and a method for measuring the groundwater level and a soil sample. The purpose is to provide a collection method.

In order to achieve the above object, the in-situ test device of the present invention is an in-situ test device for measuring the groundwater level and collecting a soil sample, and allows water to flow at intervals in the circumferential direction and the axial direction. A first pipe body with a hole and a second pipe body arranged on the outer peripheral side of the first pipe body and provided with a plurality of side openings at positions where they can be overlapped with the water passage hole. The tip of the second tube is provided with a tip port, and the tip of the first tube is projected downward from the tip port so that the tip port can be freely opened and closed. It is characterized in that a tip head portion is provided.

Further, the invention of another in-situ test device is an in-situ test device for measuring the groundwater level and collecting soil samples, in which water passage holes are perforated at intervals in the circumferential direction and the axial direction. A first pipe body and a second pipe body arranged on the outer peripheral side of the first pipe body and provided with a plurality of side openings at positions capable of being overlapped with the water passage hole are provided. A tip port is provided at the tip of the two tubes, and a tubular extension portion is extended below the tip port so that the tip port can be opened and closed. The first tubular body having a butterfly-shaped lid portion provided on the inner air side of the pipe and a slit for holding the lid portion in an open state and projecting a part from the tip opening toward the inside of the extension portion. It is characterized by having a tip head portion.

Here, the in-situ test apparatus according to any one of the above can be configured to include a third tube body having an open tip, which is arranged on the outer peripheral side of the second tube body.

On the other hand, the invention of the method for measuring the groundwater level is a method for measuring the groundwater level using the in-situ test apparatus according to any one of the above, and the first tube is inserted into the inner space of the second tube. The step of aligning the relative angles of the first tube and the second tube so that the water passage hole and the side opening do not overlap with each other, and the step of penetrating into the ground and penetrating to a desired depth. At that time, the step of rotating the first tube body or the second tube body in order to match the water passage hole with the side opening, and inserting the water level gauge in a state where the water level in the first tube body is stable. It is characterized by having a process of measuring the groundwater level.

Further, the invention of the method for collecting a soil sample is a method for collecting a soil sample using the in-situ test apparatus according to any one of the above, and the first tube is inserted into the inner space of the second tube. At the same time, a step of penetrating into the ground with the tip head portion closed and a step of pulling up the tip head portion to open the tip mouth and taking in a soil sample. It is characterized by including a step of pulling up a tube body and a second tube body.

The in-situ test apparatus of the present invention configured in this way is arranged on the outer peripheral side of the first pipe body in which water passage holes are perforated at intervals in the circumferential direction and the axial direction, and overlaps the water passage holes. It is provided with a second tubular body provided with a plurality of side openings at positions where it is possible.

Therefore, by changing the relative angle between the first pipe body and the second pipe body and aligning the positions of the water passage hole and the side opening, the height of the groundwater level in the in-situ ground can be measured accurately. ..

Further, if the configuration is such that the tip opening provided at the tip of the second tube is opened and closed by raising and lowering the tip head portion of the first tube, the configuration is simple using the tube and the first By manipulating the pipe body or the second pipe body, it is possible to surely collect a soil sample at a desired position.

Further, if a butterfly-shaped lid is provided on the inner air side of the second tubular body so that the tip opening can be opened and closed, and a tubular extension portion is extended below the openable tip opening, Whether the soil sample to be collected is sandy soil or cohesive soil, it can be collected.

By arranging the third pipe with an open tip on the outer peripheral side of the second pipe, accurate groundwater level measurement and soil sample collection can be performed even on sandy land where the hole wall is likely to collapse. It can be performed.

It is a figure explaining the structure for the measurement of the groundwater level of the in-situ test apparatus of this embodiment. It is a figure for demonstrating the triple tube structure. It is explanatory drawing which showed the structure of the upper part of the in-situ test apparatus. It is a figure explaining the structure which connects to a desired length by taking an outer pipe as an example. It is a figure explaining the method of measuring the groundwater level using the in-situ test apparatus of this embodiment. It is a figure explaining the method of collecting the soil sample of cohesive soil using the in-situ test apparatus of this embodiment. It is a figure explaining the method of collecting sandy soil. It is a figure explaining the method of collecting cohesive soil using the in-situ test apparatus of an Example. It is a figure explaining the method of collecting sandy soil using the in-situ test apparatus of an Example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 4 are views for explaining the configuration of the in-situ test apparatus 4 of the present embodiment. The in-situ test device 4 of the present embodiment is used in the in-situ of a site for constructing a small-scale building such as a detached house, a building, or a structure.

As shown in FIGS. 1 and 2, the in-situ test apparatus 4 has a triple tube structure. Here, the first pipe body having the smallest diameter and arranged inside is referred to as an inner pipe 1, the second pipe body arranged on the outer peripheral side thereof is referred to as a middle pipe 2, and the third pipe body having the largest diameter and arranged outside is used. The tube body is referred to as an outer tube 3.

The inner pipe 1, the middle pipe 2 and the outer pipe 3 are formed of, for example, steel pipes having different diameters. Further, the lengths of the inner pipe 1, the middle pipe 2 and the outer pipe 3 are not equal as described later, but are substantially the same length.

Water passage holes 11, ... Are drilled in the inner pipe 1 at intervals in the circumferential direction and the axial direction. The water passage hole 11 is formed, for example, in a circular shape. A pair of water passage holes 11 and 11 provided at the same position in the axial direction of the inner pipe 1 are provided at opposite positions 180 degrees apart in the circumferential direction, for example.

Further, in the axial direction of the inner pipe 1, paired water passage holes 11, ... Are provided at regular intervals. The positions and numbers of the water passage holes 11, ... In the circumferential direction and the axial direction are examples, and are not limited thereto.

On the other hand, the middle pipe 2 is also provided with side openings 21, ... At intervals in the circumferential direction and the axial direction. The side opening 21 is formed, for example, in an oval or elliptical shape. A pair of side opening 21 and 21 provided at the same position in the axial direction of the middle pipe 2 are located at predetermined positions at a relative angle between the inner pipe 1 and the middle pipe 2 and at the same positions as the water passage holes 11 and 11, respectively. Provided.

That is, as shown in the lower right view (vertical cross-sectional view) of FIG. 1, when the water passage hole 11 is exposed at substantially the center of the side opening 21 on a certain side surface, as shown in the upper right view (cross-sectional view) of FIG. In addition, the positions of the side opening 21 and the water passage hole 11 are the same on the back side as well. As a result, the water (groundwater) existing on the outside of the inner pipe 2 can flow into the inner space of the inner pipe 1 through the side opening 21 and the water passage hole 11.

Further, in the axial direction of the middle pipe 2, side opening 21, ... Are provided at positions where they can be overlapped with the water passage holes 11, ... At regular intervals. The positions and numbers of the side openings 21, ... In the circumferential direction and the axial direction are also examples, and the present invention is not limited to these.

On the other hand, the outer tube 3 is a tubular member that serves as an outer shell without holes or openings on the peripheral surface. Further, the tip (lowermost end) of the outer tube 3 is opened as a tip opening 31. On the other hand, as shown enlarged in FIG. 6, the tip end (lowermost end) of the middle tube 2 is also an open tip opening 24.

The tip port 24 can be opened and closed by the tip head portion 13. The tip head portion 13 protrudes downward from the tip opening 24 of the middle tube 2 in an acute angle.

Further, an annular jaw portion 132 is provided on the upper edge of the acute-angled tip portion of the tip head portion 13, and the jaw portion 132 is placed on the annular ridge portion 23 overhanging the peripheral edge of the tip opening 24. That is, when the inner tube 1 is lowered, the lower surface of the jaw portion 132 comes into contact with the upper surface of the ridge portion 23 of the middle tube 2, and only the tip of the tip head portion 13 protrudes downward from the tip opening 24. ..

The tip opening 24 and the ridge portion 23 are provided at the lower end portion 200 that can be separated from the main body of the middle pipe 2. The lower end portion 200 can be switched with the lower end portion 200A described below. When switching to the lower end portion 200A, the tip head portion 13 of the inner pipe 1 is also switched to the tip head portion 12. These switching can be easily done by making a screw connection.

As shown in FIG. 7, the lower end portion 200A is also provided with an annular ridge portion 23 protruding toward the axial center. Then, the inner space of the ridge portion 23 becomes the tip opening 24. Further, the tip opening 24 is provided with a lid portion 22 that can be opened and closed.

The lid portion 22 may have a configuration in which two semicircular semi-disks 221, 221 are connected by a hinge 222 at a diameter position. That is, the closed lid portion 22 has a substantially circular shape, and its peripheral edge is supported by the upper surface of the ridge portion 23.

The lid portion 22 is formed in a butterfly shape that opens upward by the hinge 222, and the semicircular plates 221,221 can be vertically stacked. Further, springs such as a string winding spring and a leaf spring (not shown) can be applied to the hinge 222 so that a force can be applied to the hinge 222 in the direction in which the semi-disks 221, 221 are horizontal (the direction in which the lid 22 is closed). Is provided.

Then, the tip head portion 12 capable of holding the lid portion 22 in the open state against the restoring force of the spring is attached to the tip (lowermost end) of the inner pipe 1 housed inside the middle pipe 2. ..

The tip head portion 12 is provided with a slit 121 for holding the lid portion 22 in an open state. The slit 121 is formed to have a width that can be inserted in a state where the semi-disks 221 and 221 are stacked, and is extended in the axial direction of the inner tube 1 to a length equal to or greater than the height of the semi-disks 221.

The tip head portion 12 projects downward from the tip opening 24 of the middle tube 2 in an acute angle. Further, an annular jaw portion 122 is provided on the upper edge of the acute-angled tip portion of the tip head portion 12, and the jaw portion 122 is placed on the protruding edge portion 23.

That is, when the inner tube 1 is lowered with the open lid portion 22 inserted into the slit 121, the lower surface of the jaw portion 122 comes into contact with the upper surface of the ridge portion 23 of the middle tube 2, and the tip of the tip head portion 12 becomes It is in a state of protruding downward from the tip opening 24.

FIG. 3 shows the connection structure of the upper end of the in-situ test device 4. The handle portion 41 for rotating or press-fitting the in-situ test apparatus 4 is provided with a joint portion 42 projecting downward.

The joint portion 42 is formed in a stepped shape so that the screw has a smaller diameter toward the lower side. It is composed of a cylindrical first screw portion 421 having the smallest diameter at the bottom, a second screw portion 422 immediately above the first screw portion 421, and a cylindrical third screw portion 423 having the largest diameter at the top.

The first screw portion 421 is screwed into a screw groove provided on the inner peripheral surface of the upper end 10 of the inner pipe 1. Further, a screw groove provided on the inner peripheral surface of the upper end 20 of the inner pipe 2 is screwed into the second screw portion 422. Further, a screw groove provided on the inner peripheral surface of the upper end 30 of the outer pipe 3 is screwed into the third screw portion 423.

By connecting the inner pipe 1, the middle pipe 2 and the outer pipe 3 to the joint portion 42 in this way, the triple pipe can be handled integrally. It is also possible to remove only the outer pipe 3 from the third screw portion 423 so that the outer pipe 3 can be penetrated first.

Here, the inner pipe 1, the middle pipe 2, and the outer pipe 3 are formed in total length by connecting single pipes having a predetermined length in order to obtain a desired length. Explaining the outer pipe 3 shown in FIG. 4 as an example, the single pipes 32A and 32B are provided with a female screw portion 321 at the upper end and a male screw portion 322 at the lower end.

Therefore, the single pipes 32A and 32B can be connected to each other by screwing the male screw portion 322 of the upper single pipe 32A into the female screw portion 321 of the lower single pipe 32B. This connection is repeated every time the penetration for the length of the single tube 32B is completed.

Next, a method of measuring the groundwater level using the in-situ test device 4 of the present embodiment and a method of collecting a soil sample will be described. In the present embodiment, the case where the ground G at the in-situ position is the viscous ground and the case where the ground G is sandy will be described. The cohesive soil is assumed to be cohesive soil with a relatively high water content such that the fine grain content exceeds 50%. In addition, the sandy soil is assumed to be sandy soil where the collapse of the hole wall is likely to occur.

First, as shown in FIG. 2, the inner pipe 1 is inserted into the inner space of the middle pipe 2. In this figure, the tip head portions 12 and 13 are not shown at the tip of the inner pipe 1, but the tip head portion 13 is attached to the inner pipe 1 arranged at the tip of the inner pipe 1 when collecting on a viscous ground. , The tip head portion 12 is attached when collecting on sandy ground.

Further, the outer pipe 3 is arranged on the outer peripheral side of the middle pipe 2. As shown in FIG. 3, the upper ends 10, 20, and 30 of the inner pipe 1, the middle pipe 2, and the outer pipe 3 are connected to the joint portion 42.

The relative positional relationship between the inner pipe 1, the middle pipe 2, and the outer pipe 3 when penetrating into the ground G is as shown on the left side of FIG. That is, in the axial direction (vertical direction), the tip of the outer pipe 3 penetrates deepest into the ground G, and the lower end (protruding edge 23) is arranged above the tip of the middle pipe 2 from the tip opening 24 of the middle pipe 2. , The acute-angled portion of the tip head portion 13 (12) of the inner tube 1 is projected.

Further, the two water passage holes 11, ... Of the inner pipe 1 are aligned with the positions of the side openings 21 of the middle pipe 2 in the axial direction, respectively. The tubes are stacked. Further, in the circumferential direction of the inner pipe 1 and the middle pipe 2, the relative angle is adjusted so that the side opening 21 and 21 and the water passage holes 11 and 11 do not overlap.

For example, as shown in the upper left figure of FIG. 1, the alignment is performed so that the direction between the water passage holes 11 and 11 facing each other and the direction between the side openings 21 and 21 are substantially orthogonal to each other in a plan view.

Such relative alignment of the inner pipe 1, the middle pipe 2, and the outer pipe 3 is adjusted by the amount of screwing of the joint portion 42 into each threaded portion (421, 422, 423).

Then, with the handle portion 41, the in-situ test device 4 having a triple pipe structure in which the inner pipe 1, the middle pipe 2 and the outer pipe 3 are integrated is penetrated into the ground G. Here, if a Swedish sounding test or the like has been performed in advance, the tip of the in-situ test device 4 is inserted into the test hole.

The in-situ test device 4 is press-fitted by pressing the handle portion 41 downward while rotating the handle portion 41. If the desired depth has not been reached when the penetration by the length connected to the joint portion 42 is completed for the first time, the joint portion 42 is temporarily removed for the inner pipe 1, the inner pipe 2, and the outer pipe 3. Add each of the single pipes.

When the tip reaches a desired depth by repeating press-fitting and connection in this way, the joint portion 42 is released and the handle portion 41 is removed. Subsequently, the inner pipe 1 or the middle pipe 2 is rotated to change the relative angle in the circumferential direction by 90 degrees so that the water passage holes 11 and 11 and the side openings 21 and 21 coincide with each other for alignment. (See the right side of Fig. 1).

When left to stand for a while in this state, the groundwater flowing in from the tip opening 31 of the outer pipe 3 rises in the gap between the outer pipe 3 and the middle pipe 2. Further, the inflowing groundwater will flow into the inner space of the inner pipe 1 through the side opening 21 and the water passage hole 11.

As shown in FIG. 5, the water level of the inner pipe 1 becomes substantially equal to the groundwater level W of the ground G with the passage of time. Therefore, the water level sensor 51 as a water level gauge suspended from the cable 52 is lowered into the inner space of the inner pipe 1 to measure the position (height) of the water surface.

That is, if the water level sensor 51 is lowered while the cable 52 is extended, it can be confirmed by the display of the water level measuring instrument 5 when it comes into contact with the water surface, so that the position (high) of the groundwater level W is determined from the insertion length of the cable 52 at that time. ) Is specified.

Subsequently, a soil sample is collected. FIG. 6 is an enlarged view of the vicinity of the tip of the in-situ test apparatus 4. With reference to this figure, a method of collecting a soil sample of the viscous soil of the present embodiment will be described.

When it is assumed that the ground G to be collected is cohesive soil, the tip head portion 13 is attached to the tip of the inner pipe 1 and the lower end portion 200 is attached to the tip of the middle pipe 2 as described above. The intrusion work is being carried out.

The left figure of FIG. 6 shows the state at the time of intrusion or the measurement of the groundwater level W. In this initial state, the tip port 24 of the middle tube 2 is closed by the tip head portion 13. By penetrating in such a state, it is possible to prevent sediment having an unintended depth from being mixed into the middle pipe 2.

In the in-situ test apparatus 4 of the present embodiment, the sampling means is composed of the tip head portion 13 and the cavity of the lower end portion 200 provided with the tip port 24. As shown in the central view of FIG. 6, when only the inner pipe 1 is pulled up or the position of the inner pipe 1 is fixed and the middle pipe 2 is pushed down, earth and sand are taken into the inner space of the middle pipe 2 from the tip port 24.

In this way, the soil sample G1 is housed inside the middle pipe 2 (lower end portion 200) between the tip end port 24 and the tip head portion 13. When the soil sample G1 is cohesive soil, the adhesive force to the middle pipe 2 is large, and the ridge portion 23 is caught. Therefore, even if the middle pipe 2 and the inner pipe 1 are pulled up as they are, the soil sample G1 will come first. It is collected without leaking from the end opening 24.

Next, a method of collecting soil samples from sandy soil will be described. When it is assumed that the ground G to be collected is sandy soil, the tip head portion 12 is attached to the tip of the inner pipe 1 and the lower end portion 200A is attached to the tip of the middle pipe 2. The above-mentioned intrusion work is being carried out.

FIG. 7 is an enlarged view of the vicinity of the tip of the in-situ test apparatus 4. The left figure of FIG. 7 shows the state at the time of intrusion or the measurement of the groundwater level W. In this initial state, the lid portion 22 opened in the slit 121 of the tip head portion 12 of the inner tube 1 is housed, and the tip opening 24 of the middle tube 2 is closed by the tip head portion 12. By penetrating in such a state, it is possible to prevent sediment having an unintended depth from being mixed into the middle pipe 2.

In the in-situ test apparatus 4 switched to the lower end portion 200A and the tip head portion 12, the sampling means is composed of the tip head portion 12 and the lid portion 22. As shown in the central view of FIG. 7, when only the inner pipe 1 is pulled up, if the ground G is sandy soil saturated with groundwater, the earth and sand will flow from the tip port 24 into the inner space of the middle pipe 2. If the ground G is difficult for earth and sand to flow into, the earth and sand can be taken in by pushing only the middle pipe 2.

This inflow of earth and sand will continue as long as the semi-discs 221,221 are supported by the tip head portion 12 and the lid portion 22 is open. Then, as shown in the right figure of FIG. 7, when the lid portion 22 comes out from the slit 121 of the tip head portion 12, the semi-disks 221, 221 fall down due to the restoring force of the spring provided on the hinge 222, and the tip opening 24 Is closed by the lid 22.

In this way, the soil sample G2 of sandy soil is housed inside the middle pipe 2 between the lid portion 22 and the tip head portion 12. When the middle pipe 2 and the inner pipe 1 are pulled up in this state, the soil sample G2 is collected without leaking from the tip port 24.

Next, the operation of the in-situ test apparatus 4 of the present embodiment, the method for measuring the groundwater level using the apparatus 4, and the method for collecting the soil sample will be described.

The in-situ test apparatus 4 of the present embodiment configured in this way is arranged on the inner pipe 1 in which the water passage holes 11, ... Are perforated at intervals in the circumferential direction and the axial direction, and on the outer peripheral side thereof. It is provided with a middle pipe 2 provided with a plurality of side openings 21, ... At positions where the water passage holes 11, ... Can be overlapped with each other.

Therefore, by rotating either the inner pipe 1 or the middle pipe 2 to change the relative angle and aligning the positions of the water passage holes 11, ..., And the side opening 21, ..., the original position The height of the groundwater level W of the ground G in the above can be measured accurately.

Further, if the collecting means is composed of the tip head portions 13 and 12 of the inner tube 1 and the lower end portions 200 and 200A so that the tip port 24 can be freely opened and closed, a simple configuration using the tube body is provided. In addition, by operating the inner pipe 1 or the middle pipe 2, soil samples G1 and G2 at desired positions such as cohesive soil and sandy soil can be reliably collected.

That is, since cohesive soil has a high adhesive force, it can be easily collected simply by providing a cavity at the lower end 200. On the other hand, in the case of sandy soil, a butterfly-shaped lid 22 is provided on the inner air side of the lower end 200A so that the tip port 24 can be opened and closed as a collecting means, and the lid 22 is held in an open state. By providing the inner tube 1 with the tip head portion 12 having the slit 121 to be operated, the restraint of the semi-disks 221,221 can be released and the lid portion 22 can be closed only by pulling up the inner tube 1.

By arranging the outer pipe 3 having the tip opening 31 on the outer peripheral side of the inner pipe 2, accurate measurement of the groundwater level W and soil sample G2 can be performed even in sandy land where the hole wall is very likely to collapse. Will be able to collect.

Hereinafter, examples of an embodiment different from the above-described embodiment will be described with reference to FIGS. 8 and 9. The same or equivalent parts as those described in the above-described embodiment will be described with the same terms or the same reference numerals.

In this embodiment, the in-situ test apparatus 4A having a different sampling means from the above embodiment will be described. As shown in FIGS. 8 and 9, the sampling means of the in-situ test apparatus 4A includes the tip head portion 12 described in the above embodiment, the tip opening 24A that can be opened and closed by the lid portion 22, and the tip opening 24A below the tip opening 24A. It is mainly composed of an extension portion 25 extended in a tubular shape.

An annular ridge portion 23A protruding toward the axial center from the inner wall surface above the opening 27 at the lowermost end is provided in the lower part of the middle pipe 2A which is the second pipe body of the in-situ test apparatus 4A. The narrow portion of the middle pipe 2A surrounded by the ridge portion 23A serves as the tip opening 24A.

Then, the tip head portion 12 attached to the tip of the inner tube 1 described in the above embodiment is fitted into the tip port 24A. The extension portion 25 that projects the lower end of the tip head portion 12 is provided with an annular lower protrusion 26 that projects from the periphery of the opening 27.

As shown in FIG. 8, the in-situ test device 4A penetrates into the ground G with the tip port 24A blocked by the tip head portion 12. By penetrating in such a state, it is possible to prevent the unintended depth of earth and sand from being mixed into the space above the extension portion 25. Then, in this blocked state, the groundwater level W is measured by the same method as described in the above embodiment.

Subsequently, when collecting a soil sample, the inner pipe 1 is pulled up as shown in FIG. 9, and the earth and sand are allowed to flow in when the lid portion 22 is open, and the tip head portion 12 is completely pulled up. The semi-discs 221,221 are tilted down and the tip opening 24A is closed by the lid portion 22.

When the ground G to be collected is sandy ground, the sandy soil sample G4 is housed inside the middle pipe 2 between the lid portion 22 and the tip head portion 12. On the other hand, when the ground G to be collected is a viscous ground, the lid portion 22 may not be closed due to the adhesive force even if the inner pipe 1 is pulled up, but the soil contained in the extension portion 25 is as shown in FIG. The sample G3 is collected without leaking from the opening 27 due to the adhesive force of the cohesive soil or the catching of the lower edge portion 26.

The in-situ test device 4A of the present embodiment configured in this way is provided with a butterfly-shaped lid 22 on the inner air side of the inner tube 2A so that the tip port 24A can be opened and closed, and the openable tip thereof. A tubular extension portion 25 is extended below the end opening 24A. Therefore, regardless of whether the soil samples G3 and G4 to be collected are cohesive soil or sandy soil, the soil samples can be collected by a single intrusion operation.
Since other configurations and actions and effects are substantially the same as those of the above-described embodiment, description thereof will be omitted.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment or the embodiment, and the design changes to the extent that the gist of the present invention is not deviated. Is included in the present invention.

For example, in the above-described embodiments and examples, the in-situ test devices 4 and 4A configured as a triple tube have been described, but the present invention is not limited to this, and the configuration of a double tube in which the outer tube 3 is omitted is used. You can also do it. In short, when the hole wall can stand on its own in a viscous ground, the third pipe that is penetrated to protect the hole wall can be omitted.

Further, in the above-described embodiments and examples, the case where the in-situ test devices 4 and 4A are penetrated into the ground G after being assembled into a triple pipe has been described, but the present invention is not limited to this. For example, the outer pipe 3 may be penetrated in advance, and the inner pipe 2 and the inner pipe 1 may be inserted into the hole protected by the outer pipe 3.

1 Inner pipe (1st pipe body)
11 Water flow hole 12 Tip head 13 Tip head 2 Middle pipe (second pipe)
21 Side opening 22 Lid 24 Tip port 3 Outer pipe (third pipe body)
31 Tip opening 4 In-situ test device 51 Water level sensor (water level gauge)
2A middle pipe (second pipe body)
24A Tip port 25 Extension 4A In-situ test device G Ground G1-G4 Soil sample W Groundwater level

Claims (5)

An in-situ test device for measuring groundwater level and collecting soil samples.
The first pipe body with water passage holes at intervals in the circumferential and axial directions, and
It is provided with a second pipe body which is arranged on the outer peripheral side of the first pipe body and is provided with a plurality of side openings at positions where it can be overlapped with the water passage hole.
A tip port is provided at the tip of the second tube body, and a tip head portion is projected downward from the tip port so that the tip port can be freely opened and closed at the tip of the first tube body. An in-situ test device characterized by being provided with. An in-situ test device for measuring groundwater level and collecting soil samples.
The first pipe body with water passage holes at intervals in the circumferential and axial directions, and
It is provided with a second pipe body which is arranged on the outer peripheral side of the first pipe body and is provided with a plurality of side openings at positions where it can be overlapped with the water passage hole.
A tip port is provided at the tip of the second tubular body, and a tubular extension portion is extended below the tip port.
It has a butterfly-shaped lid provided on the inner air side of the second tube so that the tip can be opened and closed, and a slit for holding the lid in an open state, and the tip can be opened and closed. An in-situ test apparatus characterized by having a tip head portion of the first tube body that projects a part toward the inside of the extension portion. The in-situ test apparatus according to claim 1 or 2, further comprising a third tube having an open tip, which is arranged on the outer peripheral side of the second tube. A method for measuring groundwater level using the in-situ test apparatus according to any one of claims 1 to 3.
The step of inserting the first tube into the inner space of the second tube, and
A step of aligning the relative angles of the first pipe body and the second pipe body so that the water passage hole and the side surface opening do not overlap, and penetrating into the ground.
A step of rotating the first pipe body or the second pipe body in order to match the water passage hole with the side opening at the time of penetrating to a desired depth.
A method for measuring a groundwater level, which comprises a step of inserting a water level gauge and measuring the groundwater level in a state where the water level in the first pipe is stable. A method for collecting a soil sample using the in-situ test apparatus according to any one of claims 1 to 3.
A step of inserting the first pipe body into the inner space of the second pipe body and allowing the tip head portion to close the tip mouth and penetrate into the ground.
The step of pulling up the tip head portion to open the tip opening and taking in the soil sample,
A method for collecting a soil sample, which comprises a step of pulling up the first pipe body and the second pipe body.