Sample collection device and characterization method

Abstract

To provide a sample collection device and a characterization method capable of evaluating sample properties relatively simply and inexpensively.SOLUTION: A sample collection device 1 includes drilling means 2 for drilling into a structure, recovery means 3 for collecting samples generated by the drilling, sample transport path 4 for guiding the sample from the drilling means 2 to the recovery means 3, and vacuum means 5 for applying suction to the sample transport path 4. The drilling means 2 includes a hammer drill 20 having a swivel 21, a hollow rod 22, and a hollow bit 23. The swivel 21 has an inner tube member 24 mounted on the base end of the hollow rod 22 and an outer tube member 25 that is externally mounted on the inner tube member 24 and rotatably holds the inner tube member 24. The hollow bit 23 has a suction port 233 formed therein, capable of suctioning granular or powdered samples generated by drilling into the structure.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a sampling device and a characterization method. [Background technology]

[0002] Samples may be taken from existing concrete structures and their characteristics evaluated. For example, during the decommissioning of a nuclear facility, samples taken from the building may be checked for the presence or absence of radioactive materials before the building is demolished. During the decommissioning of a nuclear facility, a large volume of waste material is generated from the building, but not all of it contains radioactive materials. Therefore, if the characteristics of samples taken from multiple locations on the building can be evaluated to properly identify areas that contain radioactive materials and areas that do not, these can be properly separated, which will enable cost reduction and reduction in the amount of radioactive waste.

[0003] Core drilling is generally used to collect samples from concrete structures. The samples collected by core drilling are then cut into layers in the depth direction, pre-processed by crushing, etc., and then subjected to sample preparation before being measured using a large-scale radioactivity measuring device. Since the large-scale radioactivity measuring device is installed at an accredited measurement research institution far from the collection site, the collected samples must be transported. As such, measuring samples containing radioactive materials is time-consuming, laborious, and costly. Furthermore, because core drilling requires a relatively large diameter, there is a concern that collecting multiple samples may weaken the strength of the structure. For this reason, samples collected by core drilling are limited to representative locations.

[0004] Patent Document 1 discloses a method in which a sample generated by drilling is collected, separated into a solid sample and a gas using a filter unit, and the presence or absence of radioactive material in the solid sample removed from the filter unit is measured using a large-scale radioactivity measuring device. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2023 / 275443 Summary of the Invention [Problem to be solved by the invention]

[0006] In the measurement method of Patent Document 1, the process of removing the sample from the filter unit is time-consuming. Furthermore, the removed sample must be transported to a certified measurement research institute that possesses a large-scale radioactivity measurement device. Thus, conventional measurement methods are time-consuming, labor-intensive, and costly. Furthermore, the filter unit used to collect the sample must be disposed of as secondary waste.

[0007] An object of the present invention is to provide a sampling device and a characteristic evaluation method that can evaluate the characteristics of a sample relatively easily and inexpensively. [Means for solving the problem]

[0008] To solve the above problems, the present invention provides a sample collection device comprising: a drilling means for drilling a hole in a structure; a recovery means for recovering a sample generated by drilling; a sample transport path for guiding the sample from the drilling means to the recovery means; and a pressure reducing means for applying a suction force to the sample transport path. The drilling means comprises a hammer drill having a swivel, a hollow rod, and a hollow bit. The swivel has an outer tubular member fitted over the hollow rod and rotatably holding the hollow rod. The hollow rod is formed with a first flow path leading to the hollow bit and a second flow path intersecting the first flow path. The outer tubular member is formed with a third flow path connecting the second flow path to the sample transport path. The hollow bit is formed with a suction port capable of sucking in the granular or powdery sample generated by drilling the structure. The swivel may also comprise an inner tubular member attached to the base end of the hollow rod and an outer tubular member fitted over the inner tubular member and rotatably holding the inner tubular member. In this case, the second flow passage is formed in the inner cylindrical member.

[0009] A characteristic evaluation method for collecting samples from a structure using the sample collection device and evaluating the characteristics of the samples includes a step of drilling holes in the structure using the drilling means and collecting the samples generated by the drilling, and a step of evaluating the characteristics of the granular or powdery samples collected by the collection means using a portable measuring device.

[0010] This sample collection device and characteristic evaluation method can collect granular or powdered samples, eliminating the need for sample preparation during measurement and offering excellent workability. Furthermore, since measurements are performed on granular or powdered samples, no large-scale equipment is required, and portable measurement devices can be used. This eliminates the need to transport samples containing radioactive materials. Furthermore, since large-diameter holes, such as those required for core boring, are not required, the impact on the bearing capacity and strength of the structure is minimal. Therefore, multiple samples can be collected from a single structure.

[0011] It is desirable that the hollow bit has a groove formed on its side surface, and that the suction port opens facing the groove. This creates an air flow in the groove, which guides the sample into the groove, allowing the sample to be efficiently sucked through the suction port. It is also desirable that the tip of the hollow bit has a first blade and a second blade perpendicular to the first blade, the first blade protruding beyond the second blade, and the groove continuing from the corner between the first blade and the second blade.

[0012] When the recovery means has a main body formed of an inverted truncated cone-shaped cylinder, a lid covering the upper end of the main body, and a recovery container provided at the lower end of the main body, it is desirable that the sample transport path be connected to the side of the recovery means and the pressure reducing means be connected to the lid. In this way, the sample guided to the main body falls while rotating within the main body and is recovered in the recovery container. The recovery container can then be set in a measuring device to evaluate the sample characteristics. [Effects of the Invention]

[0013] The sample collection device and characteristic evaluation method of the present invention make it possible to collect samples from multiple locations while minimizing the impact on the bearing capacity and strength of a structure, and also makes it possible to evaluate the characteristics of the samples relatively easily and inexpensively. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram showing a sample collection device. [Figure 2] 1A and 1B are diagrams showing an outline of a swivel, in which (a) is a cross-sectional view and (b) is a cross-sectional view taken along the line AA in (a). [Figure 3] 1A and 1B are diagrams showing a hollow bit, in which (a) is a perspective view and (b) is a side view. [Figure 4] FIG. [Figure 5] FIG. 2 is an explanatory diagram of the flow of a sample in a recovery means. [Figure 6] FIG. 10 is a perspective view showing a hollow bit according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] In this embodiment, a case will be described in which a sample is collected from an existing concrete structure and its characteristics are evaluated. Samples are collected from concrete structures using a sampling device 1. FIG. 1 shows the sampling device 1. As shown in FIG. 1, the sampling device 1 includes a drilling means 2, a recovery means 3, a sample transport path 4, and a decompression means 5.

[0016] The drilling means 2 is a device for drilling holes in concrete structures. The drilling means 2 is mainly composed of a hammer drill 20 that drills holes by combining rotation with impact vibration, and has a swivel 21, a hollow rod 22, and a hollow bit 23. The swivel 21 is shown in Figure 2, and the hollow bit 23 is shown in Figure 3.

[0017] As shown in FIGS. 2( a) and 2(b), the swivel 21 includes an inner cylindrical member 24 attached to the base end of a hollow rod 22 and an outer cylindrical member 25 fitted to the inner cylindrical member 24. The swivel 21 is capable of bearing the radial load (circumferential lateral vibration force) and axial load (axial pressing force) of the hammer drill 20. The inner cylindrical member 24 is a tubular member and communicates with a hollow rod 22 having a hollow cylindrical body. In this embodiment, a hollow rod 22 having an outer diameter of approximately 20 mm is used. The inner cavities of the inner cylindrical member 24 and the hollow rod 22 form a first flow path 211. As shown in FIG. 2(b), the inner cylindrical member 24 is formed with a second flow path 212 that intersects with the first flow path 211. The outer cylindrical member 25 rotatably holds the inner cylindrical member 24 via a bearing 251. The outer cylindrical member 25 is formed with a third flow path 213 that can communicate with the second flow path 212. The second flow path 212 and the third flow path 213 face a gap 214 between the inner tubular member 24 and the outer tubular member 25 , and the second flow path 212 and the third flow path 213 communicate with each other through this gap 214 .

[0018] As shown in FIG. 3, the hollow bit 23 is a hollow member with cutting blades (first blade 231 and second blade 232) formed at its tip and is used to cut concrete structures. In this embodiment, a hollow bit 23 with an outer diameter of 25 mm is used. As shown in FIG. 3(a), the tip of the hollow bit 23 is formed with a first blade 231 and a second blade 232 that is perpendicular to the first blade 231, forming a cross shape. The cross-shaped cutting edges (first blade 231 and second blade 232) enhance durability against impact vibration. In this embodiment, the cutting edges are formed with fine diamond powder to generate minute concrete cutting powder. In this embodiment, the first blade 231 crosses the second blade 232 at the intersection of the first blade 231 and the second blade 232, forming a cross shape. Although not shown, the first blade 231 may protrude beyond the second blade 232.

[0019] As shown in FIG. 3(b), the hollow bit 23 is formed with a suction port 233 that can suck in granular or powdery samples generated by drilling a concrete structure. The suction port 233 communicates with a hollow portion 235 inside the hollow bit 23. A groove 234 is formed on the side surface of the hollow bit 23, and the suction port 233 opens toward the groove 234. The groove 234 continues from the corner between the first blade 231 and the second blade 232. In other words, the groove 234 extends from between the first blade 231 and the second blade 232 toward the hollow rod 22.

[0020] The recovery means 3 recovers samples generated by drilling. Figure 4 shows the recovery means 3. The recovery means 3 has a main body 31 made of an inverted truncated cone-shaped cylinder, a lid 32 that covers the upper end of the main body 31, and a recovery container 33 provided at the lower end of the main body 31. A sample transport path 4 is connected to the side of the recovery means 3.

[0021] The lower end of the main body 31 is open and is inclined with respect to the central axis of the main body 31. An aspirating tube 54 extending from the pressure reducing means 5 is connected to the lid 32. The tip of the aspirating tube 54 passes through the lid 32 and is located inside the main body 31 (in this embodiment, at the top of the main body 31). The lower end of the main body 31 is open. The collection container 33 is provided to cover the lower end of the main body 31. The sample that flows into the main body 31 falls into the collection container 33.

[0022] The sample transport path 4 guides the sample from the drilling means 2 to the recovery means 3. As shown in FIG. 1, one end of the sample transport path 4 is connected to the outer tubular member 25 (swivel 21), and the other end of the sample transport path 4 is connected to the side of the recovery means 3. The sample transport path 4 is connected to the third flow path 213 of the swivel 21. In other words, the sample transport path 4 is connected to the first flow path 211 and the second flow path 212 via the third flow path 213.

[0023] The pressure reducing means 5 applies a suction force to the sample transport channel 4. As shown in FIG. 1 , the pressure reducing means 5 of this embodiment includes a compressor 51, a filter 52, and an ejector 53. The compressor 51 is connected to the filter 52 via an air supply pipe 55. When the compressor 51 is driven, compressed air is pressure-fed from the compressor 51 toward the filter 52. The ejector 53 is provided between the compressor 51 and the filter 52. The base end of a suction tube 54, which is connected to the cover 32 of the recovery means 3, is connected to the ejector 53. When compressed air is pressure-fed from the compressor 51 toward the filter 52, the flow of compressed air creates a negative pressure at the connection point of the suction tube 54 with the ejector 53, and the pressure inside the recovery means 3 is reduced via the suction tube 54. When the recovery means 3 is depressurized, an air flow is formed in the sample transport channel 4 from the hole-making means 2 toward the recovery means 3. The sample sucked through the suction port 233 of the hollow bit 23 is transported into the recovery means 3 via the sample transport path 4 .

[0024] Next, a characteristic evaluation method for collecting a sample from a concrete structure and evaluating its characteristics will be described. The characteristic evaluation method includes a sample collection step and a characteristic evaluation step.

[0025] In the sampling process, a sample is collected from a concrete structure using the sampling device 1. In the sampling process, holes are drilled in the concrete structure using the hole-drilling means 2, and the samples generated by the drilling are collected. In this embodiment, based on a pre-created sampling plan, the dividing line of the concrete block, the sample collection position, and the sample ID are marked on the surface of the concrete body, and holes are drilled at those positions. When the sampling device 1 is operated, holes are drilled using the hammer drill 20, and the compressor 51 is started to collect the sample. When the compressor 51 is started, negative pressure is created in the collection means 3, and the sample is sucked in through the suction port 233 of the hollow bit 23. The sucked sample is transported to the collection means 3 via the sample transport path 4.

[0026] Inside the main body 31 of the collection means 3, suction is performed from the tip of the suction tube 54 inserted into the center of the upper part of the main body 31. As shown in FIG. 5, an upward airflow is formed in the center of the main body 31, and air in the collection container 33 is sucked into the suction tube 54. At the same time, a spiral airflow is formed along the inner surface of the main body 31 from the sample transport path 4 connected to the side of the main body 31. Therefore, within the main body 31, the sample P that flows in via the sample transport path 4 connected to the side of the main body 31 rotates and descends along the inner surface of the main body 31 due to the spiral airflow. The lower end of the main body 31 is notched at an angle, and the sample P is discharged from this notch and placed into the collection container 33. In this embodiment, a sample ID label is displayed in advance on the collection container 33, making it possible to identify the collection site.

[0027] In the characteristic evaluation process, a portable measuring device (not shown) is used to evaluate the characteristics of the granular or powdery sample collected in the collection means 3 (collection container 33). In this embodiment, the collection container 33 is removed from the main body 31 and placed in the measuring device, and the characteristics of the sample inside are evaluated (measurement of radioactivity concentration). The radioactivity concentration of the collected sample is measured, and the classification level of the radioactive waste is determined.

[0028] In this embodiment, the radioactivity concentration measurement results of samples are managed for each location and input into a building model, allowing the radioactive contamination profile and radioactivity concentration distribution to be visualized in three dimensions on a 3D model. Also, attribute data of contaminated concrete parts in the building model is used to calculate the amount of concrete for each radioactive waste level classification. Furthermore, the timeline function of the building model presents a radioactive contamination profile on a time axis that takes into account the decay associated with the half-life of radioactive nuclides.

[0029] The sampling device 1 of this embodiment can collect granular or powdered samples, eliminating the need for sample preparation before measurement and providing excellent operability. Furthermore, since measurements are performed on granular or powdered samples, no large-scale equipment is required, and portable measuring devices can be used. This eliminates the need to transport samples containing radioactive materials.

[0030] By visualizing the results of radioactivity measurements on the building model, the distribution and extent of radioactive contamination becomes clear, which can be used to evaluate the quantity of waste and for demolition planning, thereby improving work efficiency.

[0031] The availability of portable measuring equipment allows for rapid on-site analysis, and by determining the amount of contaminant (radioactivity concentration) in the contaminated material at incremental distances, it is possible to repeat the drilling, collection, and analysis steps at different locations within the building and create a profile of the radioactive contamination of the concrete. Furthermore, since it does not require drilling large diameter holes like core boring, it has little effect on the bearing capacity and strength of the structure, and therefore many samples can be collected from a single structure.

[0032] A groove is formed on the side surface of the hollow bit 23, and the suction port 233 opens facing the groove, so that an air flow is formed in the groove. As a result, the sample produced by cutting is guided into the groove, and the sample can be efficiently sucked from the suction port 233. The collection container 33 can be set in the measuring device to evaluate the characteristics of the sample, so there is no need to transfer the sample.

[0033] The sampling device 1 is relatively small and lightweight, allowing work to be done quickly even under difficult working conditions, such as on a work platform inside a narrow structure. It also offers excellent workability and allows work to be completed in a short period of time, making it highly safe. In addition, since the drilled hole diameter is small, samples can be collected in a short time, making it easy to work with.

[0034] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and each of the above-described components can be appropriately modified within the scope of the present invention. In the above embodiment, the case where the swivel 21 is provided with the inner tubular member 24 and the outer tubular member 25 has been described, but the swivel 21 may also be provided with an outer tubular member that is fitted around the hollow rod 22 and rotatably holds the hollow rod 22. That is, when the swivel 21 is fitted around the hollow rod 22, the inner tubular member 24 may be omitted. In this case, a second flow path is formed in the hollow rod 22.

[0035] In the above embodiment, the first blade 231 and the second blade 232 protrude in a cross shape at the tip of the hollow bit 23, but the shape of the hollow bit 23 is not limited thereto. For example, as in a hollow bit 23a shown in Fig. 6, a cross-shaped recess 236 may be formed at the tip. [Explanation of symbols]

[0036] 1. Sampling device 2. Drilling method 20 Hammer drill 21 Swivel 211 First Channel 212 Second flow path 213 Third flow path 22 hollow rod 23 Hollow Bit 231 First blade 232 Second blade 233 Suction port 234 Groove 24 Inner cylinder member 25 Outer cylinder member 3. Recovery methods 31 Main body 32 Lid 33 Collection container 4. Sample transport path 5. Pressure reduction means 51 Compressor 52 filters 53 Ejector A. Air P sample

Claims

1. A drilling means for drilling a hole in a structure; a recovery means for recovering samples generated by drilling; a sample transport path that guides the sample from the boring means to the recovery means; a pressure reducing means for applying a suction force to the sample transport path, the drilling means comprises a hammer drill having a swivel, a hollow rod, and a hollow bit; the swivel has an outer cylindrical member that is fitted around the hollow rod and rotatably holds the hollow rod, The hollow rod is formed with a first flow path leading to the hollow bit and a second flow path intersecting the first flow path, a third flow path that communicates the second flow path with the sample transport path is formed in the outer cylindrical member, A sample collection device characterized in that the hollow bit is formed with a suction port that can suck in the granular or powdery sample generated by drilling the structure.

2. A drilling means for drilling a hole in a structure; a recovery means for recovering samples generated by drilling; a sample transport path that guides the sample from the boring means to the recovery means; a pressure reducing means for applying a suction force to the sample transport path, the drilling means comprises a hammer drill having a swivel, a hollow rod, and a hollow bit; the swivel includes an inner cylindrical member attached to a base end of the hollow rod, and an outer cylindrical member fitted to the outer surface of the inner cylindrical member and rotatably holding the inner cylindrical member, the inner cylindrical member is formed with a first flow path communicating with the hollow rod and a second flow path intersecting the first flow path, a third flow path that communicates the second flow path with the sample transport path is formed in the outer cylindrical member, A sample collection device characterized in that the hollow bit is formed with a suction port that can suck in the granular or powdery sample generated by drilling the structure.

3. A groove is formed on the side surface of the hollow bit, 3. The sample collecting device according to claim 1, wherein the suction port is open to face the groove.

4. A first blade and a second blade perpendicular to the first blade are formed at the tip of the hollow bit, The first blade protrudes further than the second blade, 4. The sample collecting device according to claim 3, wherein the groove continues from a corner between the first blade and the second blade.

5. the recovery means has a main body formed of an inverted truncated cone-shaped cylinder, a lid covering an upper end of the main body, and a recovery container provided at a lower end of the main body, The sample transport path is connected to a side of the recovery means, 3. The sample collecting device according to claim 1, wherein the pressure reducing means is connected to the lid portion.

6. A characteristic evaluation method for collecting a sample from a structure using the sampling device according to claim 1 or 2 and evaluating characteristics of the sample, comprising: a step of drilling holes in the structure using the drilling means and collecting samples generated by the drilling; and a step of evaluating the characteristics of the granular or powdery sample collected by the collecting means using a portable measuring device.

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