JP2003129460A - Sampler for soil sample - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the consolidation and compression of a soil sample due to pressurization of borehole water, a decrease in rate of soil sampling due to a phenomenon in which a layer is shoved aside, and the disarrangement of the soil samples due to percolation of the borehole water. SOLUTION: In an outer tube 24, an upper end is coupled integrally to an upper sampler head 22 which is coupled integrally to a lower end of a boring rod 21, and a metal crown 15 is coupled integrally to a lower end. An inner tube 31 also serves as a non-rotational sampling tube which is fitted into the outer tube 24 via a ball bearing device 30. An upper end is coupled integrally to a lower sampler head 23, which is structurally integrated with the sampler head 22 in a two-stage manner, between the outer tube 24 and the inner tube 31; and a bulkhead outer tube 28, whose lower end is coupled to integrally the metal crown 25, is fitted so that a triple tube structure can be constituted. Thus, a borehole channel 29, along which the borehole water flows, is formed between the outer tube 24 and the outer tube 28; and the inner tube 31, in which the soil sample A is housed, is isolated from the borehole water.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soil sampler for collecting a soil sample in the sampling (sampling) of a stratum performed for the purpose of geological survey. 2. Description of the Related Art As shown in FIG. 3, a conventional soil sampler is integrally connected to a lower end of a hollow boring rod 1 which is rotationally driven by a boring machine (not shown) installed on the ground. Sampler head 2, a cylindrical outer tube 3 having an upper end integrally connected to the sampler head 2, and a non-rotating sample collection fitted into the outer tube 3 via a ball bearing device 4. Cylindrical inner tube 5 also serving as tube
A plurality of drilling water discharge ports 7 are integrally formed with the lower end of the outer tube 3 and are formed at the upper portion of the metal crown cutting edge 6 fixed to the peripheral edge of the lower end. A metal crown 9 having a blocking packing 8 attached to the inner periphery at the lower end of the inner tube 5 at the inner periphery thereof, and an upper end fixed to the above-ground equipment, inserted into the inner tube 5 and fixed without rotation Hexagonal rod 10 for holding the sampling position of the above, and a piston rubber 1 integrally connected to the lower end of the piston hexagonal rod 10 and closely contacting the inner periphery of the inner tube 5 on the outer periphery
1 is mounted on the piston body 12. At the time of sampling, the outer tube 3 is propelled while rotating by applying rotation and propulsion to the sampler head 2 by the boring rod 1, and the cutting edge 7 of the metal crown 9 connected to the lower end of the outer tube 3 is provided. The outer tube 3 and the inner tube 5 are settled down while shaving the stratum into a columnar shape, and the stratum stratified into a columnar shape in the sample storage chamber 13 surrounded by the inner periphery of the inner tube 5 and the bottom surface of the piston body 12. It is stored as soil sample A. At this time, since the soil sample A stored in the sample storage chamber 13 has a negative pressure acting on the sample storage chamber 13 due to the close contact between the inner pipe 5 and the piston rubber 11 of the piston main body 12, the soil sample A drops due to the negative pressure. Will be kept without having to. When the sampler is excavated to a predetermined depth, the sampler is pulled up to the ground, whereby the soil sample A can be held and collected in the sample storage chamber 13. [0004] By the way, in the geological survey, a soil sample is collected and a scholastic ability test, a room (consolidation,
Compression) test to determine the strength of the ground and to provide important data for examining the foundations of civil engineering design and construction. It is important to carry out sampling work under the condition of natural underground pressure. However, a conventional soil sampler is:
Due to the double pipe structure, drilling water sent from the pump (not shown) through the inside of the boring rod 1 and the sampler head 2 flows through the gap between the outer pipe 3 and the inner pipe 5. The metal crown 9 reaches the metal crown 9 and is blocked by a blocking packing 8 provided below the drilling water discharge port 7 of the metal crown 9 and is discharged from the drilling water discharge port 7. Therefore, since sampling is performed in a state where the inner pipe 5 is constantly pressurized by the drilling water, consolidation and compression of the soil sample A are likely to occur under the influence of the pressurization of the drilling water. In some cases, the formation of a sample may be reduced by inducing the displacement of the stratum due to the pressurization of drilling water. Further, the blocking packing 8 provided at the tip of the tal crown 9 is apt to wear due to rotational friction caused by entrainment of earth and sand, and water leakage is likely to occur. This causes the quality of the soil sample A to deteriorate. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to reduce the sampling rate of a soil sample due to the phenomenon of consolidation and compression of the soil sample due to the pressurization of drilling water and the displacement of the stratum, and to drill the hole An object of the present invention is to provide a soil sampler capable of preventing disturbance of a soil sample due to permeation of water. [0008] In order to achieve the above object, the present invention provides a sampler head integrally connected to a lower end of a boring rod driven to rotate, and an upper end integrally formed on the sampler head. A combined outer tube, an inner tube serving also as a non-rotatable sampling tube fitted into the outer tube via a ball bearing device, and an integrally connected lower end of the outer tube; A metal crown having a plurality of drilling water discharge ports formed in the upper part of the metal crown while fixing the crown cutting edge, and a piston which is inserted into the inner tube and holds a substantially constant sampling position without rotating. A soil sampler comprising: a hexagonal rod; and a piston body integrally attached to a lower end of the piston hexagonal rod, and a piston body having an outer periphery fitted with a piston rubber in close contact with the inner periphery of the inner tube. In a sampler, an upper end is integrally connected to the sampler head between the outer tube and the inner tube,
A drilling water channel in which drilling water flows between the outer pipe and the bulkhead outer pipe by fitting a bulkhead outer pipe having a lower end integrally joined to the metal crown to form a triple pipe structure. Is formed. An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a partially cutaway front view of the soil sampler of the present invention in a preparation position before sampling, and FIG. 2 is a partially cutaway front view of the soil sampler of the present invention after sampling. . As shown in FIG. 1, a soil sampler according to the present invention comprises an upper sampler head 22 and an upper sampler head 22 at the lower end of a hollow boring rod 21 which is rotationally driven by a boring machine (not shown) installed on the ground. Lower sampler head 23 slightly smaller in diameter than head 22
And are integrally connected in a two-stage integrated structure. The upper end of a cylindrical outer tube 24 is integrally connected to the outer periphery of the upper sampler head 22.
The metal crown 25 is integrally connected to the lower end of the metal crown.
The metal crown 25 has a metal crown cutting edge 26 fixed to the lower peripheral edge and the metal crown cutting edge 26.
A plurality of drilling water discharge ports 27 are formed in the upper part of the hole. The outer periphery of the lower sampler head 23 is integrally connected with the upper end of a cylindrical partition outer tube 28 fitted in the outer tube 24, and the lower end of the partition outer tube 28 is embedded in the metal crown 25. They are joined together in the state where they are made. Between the outer pipe 24 and the bulkhead outer pipe 28, an annular drilling hole through which drilling water sent from the pump through the inside of the boring rod 21 and the upper sampler head 22 and through the lateral hole 23a of the lower sampler head 23 flows. A water channel 29 is formed. A cylindrical inner tube 31 also serving as a non-rotatable sampling tube is fitted through a ball bearing device 30 in the partition outer tube 28, and the lower end of the inner tube 31 is integrated with the metal crown 25. Is bound to. Partition wall outer tube 28 and inner tube 3
1 is located between the vent hole 22 of the upper sampler head 22.
An annular air chamber 32 through which air flows in and out is formed. In the inner tube 31, a boring rod 21, an upper sampler head 22, and a lower sampler head 2 are provided.
A piston hexagonal rod 33 that extends downward through the piston body 3 is inserted, and a piston main body 34 is integrally connected to a lower end of the piston hexagonal rod 33, and the outer periphery of the piston main body 34 is in close contact with the inner periphery of the inner tube 31. The piston rubber 35 is mounted. The upper end of the piston hexagonal rod 33 is fixed to a ground facility, so that the piston hexagonal rod 33 is held at a substantially constant sampling position without rotating or vertical movement. Further, the piston hexagonal rod 33 is locked at a fixed position in a non-rotational state by a locking device 36 including a control mechanism and a pressure spring. A hexagonal key groove member 37 is engaged with the piston hexagonal rod 33, and the hexagonal key groove member 37 enables the piston hexagonal rod 33 to be displaceable relative to the inner tube 31 only in the axial direction. It is designed to prevent round trip. A blocking packing 38 is interposed between the piston hexagonal rod 33 and the lower sampler head 23, and the drilling water sent through the boring rod 21 and the upper sampler head 22 by the blocking packing 38. Is bypassed to the side hole 23a of the lower sampler head 23. In the soil sampler of the present invention,
Upper sampler head 22 by boring rod 21
By applying rotation and propulsion to the lower sampler head 23 and the lower sampler head 23, the outer tube 24 and the partition outer tube 28 are propelled while rotating, and the stratum is formed into a cylindrical shape by the cutting edge 26 of the metal crown 25 connected to the lower end of the outer tube 24. The outer tube 24, the partition wall outer tube 28, and the inner tube 31 are settled while being scraped off, and the stratum formed into a columnar shape in the sample storage chamber 39 surrounded by the inner periphery of the inner tube 31 and the bottom surface of the piston body 34 is soiled. It is stored as sample A. Sample storage chamber 39
The soil sample A stored in the sample storage chamber 3 is brought into close contact with the inner pipe 31 and the piston rubber 35 of the piston body 34.
Since a negative pressure acts on the inside 9, the negative pressure is maintained without falling off. The drilling water is supplied from the pump to an annular drilling channel 29 formed between the outer pipe 24 and the bulkhead outer pipe 28 through the inside of the boring rod 21 and the upper sampler head 22 and the horizontal hole 23 a of the lower sampler head 23. And flows down the drilling water channel 29 to reach the metal crown 25, and the drilling water discharge port 2 of the metal crown 25
It is discharged from 7. Then, the soil sample A can be held and collected in the sample storage chamber 39 by raising the sampler to the ground at the stage where the excavation has been performed to a predetermined depth. In the soil sampler of the present invention, an outer tube having an upper end integrally connected to an upper sampler head 22 integrally connected to a lower end of a boring rod 21 and a lower end integrally connected to a metal crown 25. An upper sampler head 22 and a lower sampler head 23 having a two-stage integrated structure are provided between the upper sampler head 22 and the inner tube 31 which also serves as a non-rotatable sampling tube fitted in the outer tube 24 via the ball bearing device 30. The upper end is integrally connected to the metal crown 25, and the lower end is integrally connected to the metal crown 25 to form a triple tube structure. The drilling water passage 29 through which the bore water flows is formed, and the air chamber 32 through which air flows in and out is formed between the partition outer tube 28 and the inner tube 31, so that the inner tube 31 in which the soil sample A is stored is formed. To Was isolated from the hole water can be performed sampling in a state of natural groundwater pressure. Thereby, it is possible to prevent a decrease in the sampling rate of the soil sample A due to the consolidation, compression, and displacement of the formation due to the pressurization of the drilling water. Further, in the soil sampler according to the present invention,
Since the lower end of the partition wall outer tube 28 is integrally connected to the metal crown 25, there is no need for a blocking packing for blocking the drilling water between the partition wall outer tube 28 and the inner tube 31. There is no water leakage into the inner pipe 31 due to the abrasion of the packing. Accordingly, it is possible to prevent the outflow of the soil sample A due to the leakage of the drilling water and the deterioration of the quality of the soil sample A due to the penetration of the drilling water. As described above, according to the present invention, there is provided a sampler head integrally connected to a lower end of a rotating boring rod, and an outer tube having an upper end integrally connected to the sampler head. And an inner tube that also serves as a non-rotating sample sampling tube fitted into the outer tube via a ball bearing device, and is integrally connected to a lower end of the outer tube, and a metal crown cutting edge is fixed to a lower peripheral edge. A metal crown having a plurality of drilling water discharge ports formed in the upper part of the metal crown, a piston hexagonal rod inserted into the inner tube and holding a substantially constant sampling position without rotating, It is integrally connected to the lower end of the piston hexagon rod,
In a soil sampler including a piston body having a piston rubber attached to an inner periphery of the inner tube in close contact with an inner periphery of the inner tube, an upper end is integrally connected to the sampler head between the outer tube and the inner tube. In addition, by forming a triple pipe structure by fitting a bulkhead outer pipe having a lower end integrally joined to the metal crown, a drilling water flowing between the outer pipe and the bulkhead outer pipe is formed. The formation of the borehole channel prevents a decrease in the sampling rate of the soil sample due to the compaction / compression of the soil sample due to the pressurization of the drilling water and the displacement of the stratum, and prevents the disturbance of the soil sample due to the penetration of the borehole water. As a result, the soil sample can be sampled without disturbing the ground, and no consolidation and compression of the soil sample occurs at the time of sampling, so that a good quality soil sample can be collected.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially cutaway front view of a preparation position before sampling of a soil sampler of the present invention. FIG. 2 is a partially cutaway front view of the soil sampler of the present invention after sampling. FIG. 3 is a partially broken front view of a conventional soil sampler after sampling. [Description of Signs] A Soil sample 21 Boring rod 22 Upper sampler head 23 Lower sampler head 24 Outer tube 25 Metal crown 26 Metal crown cutting edge 27 Drilling water discharge port 28 Partition wall outer tube 29 Drilling water channel 30 Ball bearing device 31 Inner tube 32 Air chamber 33 Piston hexagon rod 34 Piston body 35 Piston rubber 39 Sample storage chamber

   ────────────────────────────────────────────────── ─── Continuation of front page    F-term (reference) 2D043 AC01 BA08 BB09                 2G052 AA19 AB01 AC04 AD14 AD34                       AD54 BA02 BA29 DA15 HA01                       JA08

Claims (1)

Claims: 1. A sampler head integrally connected to a lower end of a boring rod driven for rotation, an outer tube having an upper end integrally connected to the sampler head, and a ball bearing device. And an inner tube serving also as a non-rotating type sampling tube fitted in the outer tube, and integrally connected to a lower end of the outer tube, and a metal crown cutting edge fixed to a lower peripheral edge and an upper portion of the metal crown. A metal crown having a plurality of drilling water discharge ports formed therein, a piston hexagonal rod inserted into the inner pipe and holding a substantially constant sampling position without rotating, and a lower end of the piston hexagonal rod. A soil sampler comprising a piston body mounted on the outer periphery thereof and having a piston rubber attached to the inner periphery of the inner tube in close contact with the outer periphery of the inner tube. The outer pipe and the outer wall of the partition are formed by fitting a partition outer pipe having an upper end integrally connected to the sampler head and a lower end integrally connected to the metal crown to form a triple pipe structure. A soil sampler characterized by forming a drilling channel through which drilling water flows.