JP2019019595A - Soil sampling device and soil sampling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a soil sampling device and a soil sampling method capable of collecting a soil sample with less disturbance by using a Swedish sounding test device or the like. SOLUTION: An outer pipe 1, an inner pipe 2, a screw shaft 4 having axial lines O1 arranged coaxially inside the inner pipe 2, and a screw shaft 4 provided integrally on the rear end side of the outer pipe 1. , The screw shaft 4 is integrally provided on the rear end side of the inner pipe 2 with the bearing 5 that rotatably supports the screw shaft 4 around the axis O1. A piston 7 which is connected to the tip of the push-in base 6 and the screw shaft 4 and is arranged so as to close the opening on the tip side of the inner pipe 2 in a state where the inner pipe 2 is retracted, and the outer pipe 1 It is provided with a rib 8 that is projected outward from the outer surface of the pipe and bites into the ground to prevent the outer pipe 1 from rotating, and a guide 9 that guides the push-in base 6 and the inner pipe 2 in the direction of the axis O1 to advance and retreat. [Selection diagram] Fig. 1

Description

  The present invention relates to a soil sample collection device and a soil sample collection method for collecting a soil sample with less disturbance.

  Conventionally, by collecting a soil sample with less disturbance (undisturbed sample / a soil sample with less disturbance), it is used for soil quality discrimination and various laboratory tests to obtain design constants and the like.

  Generally, when collecting a soil sample with little disturbance, a borehole is drilled in the ground with a boring machine, and a sampling tube inserted into the borehole is pushed into the ground from the bottom of the borehole to collect the soil sample. Rotating double-wall sampler, rotary sampler that collects soil samples by rotating the ground with an outer tube with a bit at the tip, and pushing the inner tube that does not rotate into the ground A triple pipe sampler is used.

  On the other hand, if a boring machine is used for ground investigation when building a small-scale building such as a house, it is large and expensive. For this reason, in the ground survey of small-scale buildings, a Swedish sounding test is often used to determine static penetration resistance (hardness of soil, tightness) using equipment consisting of rods, screw points, weights, and the like.

  A method of performing a test using a Swedish sounding test apparatus and collecting a soil sample has been proposed and put into practical use.

  For example, in Patent Document 1 and Patent Document 2, a sampler having a side surface or a soil sample collection opening is attached to the tip of a rod of a Swedish sounding test apparatus, and the sample is provided in a hole drilled by a Swedish sounding test. A method is disclosed in which a sampler is inserted and a sampler is pressed into the ground by impact penetration or rotational penetration to collect a soil sample from the soil sample collection opening.

JP 2014-173398 A JP 2014-156706 A

  However, the soil sample collection device disclosed in Patent Document 1 and Patent Document 2 described above uses a Swedish sounding test device together, and pushes a sampler into the ground by impact penetration or rotation penetration, and collects a small-diameter soil sample. Since a soil sample is collected from the opening for use, a soil sample with little disturbance cannot be collected.

  In view of the above circumstances, an object of the present invention is to provide a soil sample collection device and a soil sample collection method that can collect a soil sample with little disturbance by using a Swedish sounding test device. .

  In order to achieve the above object, the present invention provides the following means.

  The soil sample collection device of the present invention is an outer tube, an inner tube of a sampling tube that is coaxially arranged inside the outer tube and is provided so as to be movable forward and backward in the axial direction with respect to the outer tube, A screw shaft provided coaxially with each other in the inner tube, and a bearing provided integrally on the rear end side of the outer tube and rotatably supporting the screw shaft around the axis. A push base that is integrally provided on the rear end side of the inner pipe, rotates the screw shaft forward and backward around an axis and advances and retreats in the axial direction, and is connected to the tip of the screw shaft, A piston disposed so as to close the opening on the distal end side of the inner tube in a state where the tube is retracted rearward in the axial direction, and protrudes outward from the outer surface of the outer tube, and digs into the ground to A rib for preventing the circulation of the pipe, the pushing table and the inner Characterized in that the is configured to include a guide for advancing and retracting guides in the axial direction.

  The soil sample collection method of the present invention is provided with a soil sample collection device provided with an outer tube and an inner tube of a sampling tube provided inside the outer tube so as to be movable forward and backward in the axial direction by rotation of a screw shaft. The soil sample collecting device is installed by inserting a rib integrally provided in the outer pipe into the ground from the hole wall while being inserted into the hole provided, and the screw pipe is rotated forward around the axis and the inner pipe is rotated. The soil sample is introduced to the inside of the inner pipe while advancing forward and penetrating into the ground from the bottom of the hole, the screw shaft is rotated backward about the axis and the inner pipe is retracted rearward together with the inner pipe The soil sample is collected.

  In these inventions, when the screw shaft is rotated forward about the axis, the inner tube of the sampling tube can be advanced together with the pushing table together with the push-in base in the axial direction, and the screw shaft is rotated backward about the axis. And the inner tube can be retracted rearward in the axial direction together with the push-in base. In other words, the pusher base is held by the guide so that it cannot rotate around the axis and can move forward and backward in the axial direction, so if the screw shaft is rotated forward and backward around the axis, the inner tube is moved forward and backward without rotation. Can do.

  Then, the rear end side of the screw shaft is connected to a rod-shaped rod, and the soil sample is collected together with the rod in the hole drilled in the ground with the inner tube retracted so that the opening on the tip side of the inner tube is closed with a piston. Insert the device and rotate the rod to rotate the screw shaft forward.

  At this time, the soil sampling device can be inserted into the hole in the ground, and the ribs provided integrally with the outer pipe can be bitten into the hole wall of the ground so that the outer pipe can be fixed in the hole in the ground. That is, it is possible to prevent the outer tube from rotating when the screw shaft is rotated forward and backward.

  As a result, the inner pipe can be advanced forward without rotation and can be press-fitted into the ground from its tip. By pulling up the soil sampler together with the rod from the hole in the ground, the inner pipe can be pressed into the ground without rotation. It is possible to collect a soil sample with little disturbance inside.

  Further, in the soil sample collecting device of the present invention, the outer tube is detachably provided at the distal end portion, and includes a penetration portion that penetrates into the ground, and the penetration portion has a distal end on the outer surface from the rear end side in the axial direction. It is desirable that the taper portion be formed so as to be gradually inclined toward the inner surface side as it goes to.

  In the present invention, since the tip of the outer tube is provided with a tapered penetration portion, the soil sampler is inserted into the hole in the ground, and the penetration portion can be easily penetrated into the ground from the bottom of the hole in the ground. Thus, the soil sampler can be suitably held in the hole in the ground.

  Furthermore, in the soil sampling apparatus of the present invention, a rod of a Swedish sounding test apparatus may be used as the rod.

  In the present invention, the soil sample collection device can collect a soil sample with less disturbance by using the holes formed by the Swedish sounding test and using the rod of the Swedish sounding test device.

  In the soil sampling device and soil sampling method of the present invention, the rear end side of the screw shaft is connected to a rod-shaped rod, and the soil sampling device is inserted into the hole drilled in the ground together with the rod, and the rod is rotated. By rotating the screw shaft forward, the inner tube of the sampling tube can be advanced forward without rotation and can be press-fitted into the ground from the tip. Thus, by pulling up the soil sample collecting device together with the rod from the hole, it is possible to collect a soil sample with less disturbance that is pressed into the ground without rotation and enters the inner pipe.

  And since the soil sample can be collected in this way, for example, using a hole drilled by a Swedish sounding test or using a rod of a Swedish sounding test device, the soil sample is inexpensive and easily disturbed. Can be collected.

It is sectional drawing which shows the soil sample sampling apparatus which concerns on one Embodiment of this invention. It is a figure which shows the method (The soil sample collection method which concerns on one Embodiment of this invention) which collects a soil sample with little disorder using the soil sample collection device which concerns on one Embodiment of this invention, It is a figure which shows the state installed in the hole provided in the ground in the retracted state. It is a figure which shows the method (The soil sample collection method which concerns on one Embodiment of this invention) which collects a soil sample with little disorder using the soil sample collection device which concerns on one Embodiment of this invention, It is a figure which shows the state which advanced and penetrated into the ground. It is a figure which shows the method (The soil sample collection method which concerns on one Embodiment of this invention) which collects a soil sample with little disorder using the soil sample collection device which concerns on one Embodiment of this invention, and is attached to the inner tube | pipe of a sampling tube It is a figure which shows the state which pulls out the pipe | tube sampling apparatus filled with the soil sample from the hole of the ground.

  Hereinafter, a soil sample collection device and a soil sample collection method according to an embodiment of the present invention will be described with reference to FIGS.

  Here, the present embodiment relates to a soil sample collection device capable of collecting a soil sample with little disturbance using a small-diameter hole drilled in the ground by a Swedish sounding test or the like.

  Specifically, as shown in FIGS. 1 and 2, the soil sampler A of the present embodiment is formed in a cylindrical outer tube 1 and a cylindrical shape, and the axis O1 of each other is arranged on the same axis. The inner tube 2 of the sampling tube provided so as to be able to advance and retract in the direction of the axis O1 with respect to the tube 1 and the tip of the rod 3 of the Swedish sounding test apparatus, for example, are arranged coaxially with each other so that they can be attached and detached. The screw shaft 4 provided in the inside of the inner pipe 2 is connected to the end.

  The soil sampler A is integrally provided inside the rear end of the outer tube 1, and a bearing 5 that rotatably supports the screw shaft 4 around the axis O <b> 1, and a bearing 5 that is screwed onto the screw shaft 4. The inner tube 2 is provided at the front end side of the outer tube 1 and is integrally provided at the rear end side of the inner tube 2. The screw shaft 4 is rotated forward and backward around the axis O 1 and moved forward and backward in the direction of the axis O 1. A push base 6 that moves forward and backward in the direction of the axis O1 and a tip connected to the tip of the screw shaft 4 are provided, and the inner tube 2 is in close contact with the inner surface of the inner tube 2 with the inner tube 2 retracted rearward in the direction of the axis O1. 2 and a piston 7 disposed so as to close the opening on the tip side.

  The soil sampler A protrudes outward from the outer surface of the outer tube 1 and extends in the direction of the axis O1, and a plurality of ribs (liner blades) 8 that bite into the ground G and prevent the outer tube 1 from rotating. And a guide 9 that is provided on the push-in base 6 and the outer tube 1 and rotates the screw shaft 4 forward and backward around the axis O1, and guides the push-in base 6 and the inner pipe 2 forward and backward in the direction of the axis O1. .

  The guide 9 according to the present embodiment includes an engaging convex portion 9a that protrudes radially inward from the inner surface of the outer tube 1 and extends in the direction of the axis O1, and is recessed inward from the outer surface of the push-in base 6 in the direction of the axis O1 (vertical direction). ) And open to the upper end side and the lower end side, and the engagement convex portion 9a and the engagement concave portion 9b engage with each other to rotate the screw shaft 4 forward and backward. The pusher base 6 and the inner pipe 2 are guided to advance and retract.

  Further, in the soil sample collecting device A of the present embodiment, the outer tube 1 is provided with a penetrating portion 10 that is detachably provided at the tip portion thereof and penetrates into the ground G. The penetration portion 10 is provided, for example, such that a male screw is threaded on the outer surface on the rear end side, and is detachably provided by screwing on a female screw on the inner surface on the distal end side of the outer tube 1. Furthermore, the penetration part 10 is provided with the taper part 10a which inclines gradually to an inner surface side as it goes to a front-end | tip from the rear end side of an axis O1 direction to the outer surface of the front end side rather than an external thread part. The penetrating portion 10 is formed so that its inner diameter is substantially equal to the outer diameter of the inner tube 2 (slightly larger diameter dimension).

  The piston 7 is made of rubber, for example, and is connected to the tip of the screw shaft 4 so as to be relatively rotatable using a universal joint. The piston 7 has a sealing member 11 such as an O-ring integrally attached to the outer surface thereof, and is sealed to the inner surface of the inner tube 2 in a state where the inner tube 2 is retracted to the rear side in the direction of the axis O1 together with the pushing table 6. The stop member 11 (piston 7 itself) is provided in close contact and closes the opening on the tip side.

  The inner tube 2 of the sampling tube is preferably as thin as possible, but the inner tube 2 having a thickness corresponding to the soil quality may be selectively used.

  When collecting a soil sample using the soil sample collecting apparatus A of the present embodiment having the above-described configuration (in the soil sample collecting method of the present embodiment), for example, a Swedish sounding test is performed as shown in FIG. The screw point is removed from the tip of the rod 3 of the apparatus, and the rear end side of the screw shaft 4 is connected to the tip of the rod 3 to attach the soil sampling device A.

  At this time, the soil sampler A retracts the inner tube 2 together with the pushing table 6 to the rear side of the screw shaft 4, and closes the opening on the distal end side of the penetration portion 10 of the inner tube 2 and the outer tube 1 with the piston 7. The piston 7 is exposed at the tip.

  Then, a Swedish sounding test is performed, and the soil sampler A is inserted into the hole H formed in the ground G together with the rod 3 so that the penetration portion 10 at the tip of the outer tube 1 penetrates the ground G from the hole bottom H1. Then, the soil sampler A is installed at a predetermined position. In this embodiment, since the front end side of the penetration part 10 is formed in the taper shape, the penetration part 10 can be easily penetrated into the ground G, and the soil sampler A is suitably held in the hole H. The

  Further, in the soil sample collecting device A of the present embodiment, the outer surface of the outer tube 1 is provided with ribs (rotation prevention portions) 8 projecting radially outward, so that the soil sample collecting device A is installed in the hole H. In addition to being inserted, the rib 8 bites into the hole wall, and the soil sampler A is disposed at a predetermined position in the hole H in a state where the outer tube 1 is held so as not to rotate.

  Thus, when the soil sampler A is disposed at a predetermined position in the hole H, as shown in FIG. 3, the rod 3 is rotated forward around the axis O1 in the same manner as in the Swedish sounding test. At this time, since the outer tube 1 is held so as not to rotate in the hole H by the ribs 8, the pushing table 6 guided by the guide 9 does not rotate inside the outer tube 1 and moves toward the distal end side of the screw shaft 4. Move.

  At the same time, the inner pipe 2 advances and the inner pipe 2 is press-fitted (penetrated) into the ground G from the tip of the outer pipe 1 without rotation. As a result, by sequentially rotating the screw shaft 4 forward, the inner tube 2 of the sampling tube is further press-fitted in a non-rotating state, and the soil sample S enters the inner tube 2 with little disturbance.

  Further, a piston 7 rotatably provided at the tip of the screw shaft 4 via a universal joint slides relatively to the rear side of the inner tube 2 while making no contact with the inner surface of the inner tube 2 without rotation. . Due to the movement of the piston 7, the inside of the inner tube 2 on the tip side of the piston 7 is in a negative pressure state, and the soil sample S smoothly enters the inner tube 2 and also enters the inner tube 2 and is collected. It is possible to prevent the soil sample S from falling or falling out.

  When the inner pipe 2 is press-fitted into the ground by a predetermined amount and the soil sample S is collected, the rod 3 and the soil sample collecting device A are pulled up from the hole H to the ground as shown in FIG. Then, the screw shaft 4 is removed from the tip of the rod 3, the piston 7 is removed from the screw shaft 4, and the inner tube 2 is removed.

  As a result, the rear end side of the inner tube 2 of the sampling tube is closed by the piston 7, and the soil sample S collected in the inner tube 2 is sealed by drying the It can be stored while preventing collapse.

  Therefore, in the soil sample collection device A and the soil sample collection method of the present embodiment, when the screw shaft 4 is rotated forward about the axis O1, the guide tube 9 guides the inner tube 2 of the sampling tube along with the pushing table 6 along the axis line. When the screw shaft 4 can be rotated backward in the O1 direction, the inner tube 2 can be retracted rearward in the direction of the axis O1 together with the pushing table 6. That is, since the pushing table 6 is held by the guide 9 so that it cannot rotate around the axis O1 and can move forward and backward in the direction of the axis O1, when the screw shaft 4 is rotated forward and backward around the axis O1, the inner tube 2 is rotated without rotation. It can be moved back and forth in the direction of the axis O1.

  A hole drilled in the ground G in a state where the rear end side of the screw shaft 4 is connected to the rod-shaped rod 3 and the inner tube 2 is retracted so that the opening on the front end side of the inner tube 2 is closed by the piston 7. The soil sampler A is inserted and arranged in H together with the rod 3, and the rod 3 is rotated to rotate the screw shaft 4 forward.

  At this time, the soil sampler A is inserted into the hole H of the ground G, and the rib 8 provided integrally with the outer pipe 1 is bitten into the hole wall of the ground G, so that the outer pipe 1 is inserted into the hole H of the ground G. It can be fixed with. That is, it is possible to prevent the outer tube 1 from rotating when the screw shaft 4 is rotated forward and backward.

  Thereby, the inner pipe 2 can be advanced forward without rotation, and can be press-fitted into the ground G from the tip thereof. By pulling up the soil sampler A together with the rod 3 from the hole H of the ground G, the ground G can be removed. It becomes possible to collect the soil sample S with less disturbance that is press-fitted by rotation and enters the inside of the inner pipe 2.

  Therefore, according to the soil sample collection apparatus A and the soil sample collection method of the present embodiment, the soil sample S can be collected as described above. For example, the hole H formed by the Swedish sounding test can be used, By using the rod 3 of the type sounding test apparatus, it becomes possible to collect the soil sample S with less disturbance easily and inexpensively.

  In addition, in the soil sample collection device A of the present embodiment, by providing the tapered penetration portion 10 at the tip of the outer tube 1, the soil sample collection device A is inserted into the hole H of the ground G, The penetration part 10 can be easily penetrated into the ground G from the bottom of the hole H of the ground G, and the soil sampler A can be suitably held in the hole H of the ground G.

  Further, since the piston 7 is provided at the tip of the screw shaft 4, the soil sample S and the piston 7 are in close contact with each other, and the disturbance of the soil sample S can be prevented when the inner tube 2 is press-fitted.

  Further, the inner pipe 2 is advanced forward and press-fitted into the ground G, and the piston 7 is arranged relatively rearward, and a negative pressure can be generated in the inner pipe 2 by the relative movement of the piston 7; The soil sample S with less disturbance can be suitably taken inside. Further, the soil 7 can be held from the inside of the inner pipe 2 by the piston 7 (by the negative pressure generated in the piston 7).

  Furthermore, since the inner tube 2 is detachably connected to the pushing table 6, the inner tube 2 can be removed, and the inner tube 2 can be used as it is as a protective tube to store the soil sample S with less disturbance. Further, the inner tube 2 can be easily replaced, and the inner tube 2 having a thickness corresponding to the soil quality can be selectively used as appropriate.

  Further, by inserting the soil sampling device A into the hole H drilled in the ground G and connecting the piston 7 contacting the hole bottom H1 to the screw shaft 4 so as to be relatively rotatable, the screw shaft 4 is rotated around the axis O1. It is possible to prevent the piston 7 from rotating when the pushing base 6 and thus the inner tube 2 are press-fitted into the ground G. Thereby, the soil sample S with which the piston 7 comes into contact is not disturbed, and the soil sample S with less disturbance can be collected more reliably and suitably.

  In addition, since the piston 7 is detachably connected to the tip of the screw shaft 4, the inner tube 2 is removed, and the piston 7 is removed from the screw shaft 4 to close the opening of the inner tube 2. 7 can be used as a cap. Thereby, the soil sample S with little disturbance can be suitably stored so as not to cause, for example, drying by using the inner pipe 2 and further using the piston 7.

  As mentioned above, although one embodiment of the soil sample collection device and the soil sample collection method according to the present invention has been described, the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit thereof. It is.

1 Outer tube 2 Inner tube (Sampling tube)
3 Rod 4 Screw shaft 5 Bearing 6 Pushing base 7 Piston 8 Rib (Liner blade / rotation prevention part)
9 Guide 9a Engaging convex part 9b Engaging concave part 10 Penetration part 11 Sealing member A Soil sample collecting device G Ground H Hole H1 Hole bottom O1 Axis S Soil sample

Claims (4)

An outer tube,
Inside the outer tube, an inner tube of a sampling tube that is arranged coaxially with each other and is provided so as to be movable back and forth in the axial direction with respect to the outer tube;
A screw shaft provided coaxially with each other in the inner tube; and
A bearing integrally provided on the rear end side of the outer pipe, and rotatably supporting the screw shaft around an axis;
A pushing stand that is integrally provided on the rear end side of the inner pipe, rotates the screw shaft forward and backward around an axis, and advances and retreats in the axial direction;
A piston provided to be connected to the tip of the screw shaft and disposed so as to close the opening on the tip side of the inner tube in a state where the inner tube is retracted to the rear side in the axial direction;
A rib projecting outward from the outer surface of the outer tube, and a rib that bites into the ground and prevents the outer tube from rotating
A soil sample collecting apparatus comprising: a pushing table and a guide for guiding and reciprocating the inner pipe in the axial direction. The soil sampler according to claim 1,
The outer tube is detachably provided at the tip, and includes a penetration portion that penetrates into the ground.
The said penetration part is a soil sample-collecting apparatus currently provided with the taper part which inclines to the inner surface side gradually as it goes to the front-end | tip from the axial direction rear end side to the outer surface. In the soil sampling apparatus according to claim 1 or 2,
A soil sampling device using a Swedish sounding tester rod as the rod. While inserting an outer tube and a soil sampling device comprising an inner tube of a sampling tube provided inside the outer tube so as to be able to advance and retreat in the axial direction by rotation of a screw shaft, Install the soil sampling device by letting the ribs provided integrally with the outer tube dig into the ground from the hole wall,
Introducing a soil sample into the inner tube while rotating the screw shaft forward around the axis and moving the inner tube forward to penetrate the ground from the bottom of the hole,
A soil sample collecting method comprising collecting the soil sample together with the inner tube by rotating the screw shaft in the reverse direction around the axis and retracting the inner tube backward.

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