Soil separation resistance measurement device and soil separation resistance measurement method

Abstract

To provide a sediment separation resistance measuring device and a sediment separation resistance measuring method capable of properly grasping the separation resistance of sediment.SOLUTION: A soil separation resistance measurement apparatus 10 according to an embodiment includes a storage member 11 configured to store soil G, a vibration member 14 configured to apply vibration V to the soil G stored in the storage member 11, a resistivity measurement apparatus 15 configured to measure a first resistivity which is a resistivity of a first portion P1 of the soil G to which the vibration V is applied, and a second resistivity which is a resistivity of a second portion P1 different from the first portion P2 of the soil G to which the vibration V is applied, and an evaluation section 16 configured to evaluate separation resistance of the soil G from the first resistivity and the second resistivity.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a soil separation resistance measuring device and a soil separation resistance measuring method for measuring soil separation resistance. [Background technology]

[0002] Patent Document 1 describes a geological exploration device used to explore the geology of the surrounding natural ground when excavating a roof shield tunnel. The geological exploration device is mounted on a tunnel boring machine that excavates the roof shield tunnel and has a resistivity sensor that measures the resistivity of the natural ground.

[0003] The resistivity sensor is mounted on the outer peripheral surface of the rotary cutter of the tunnel boring machine. The resistivity sensor has a base and five electrodes mounted on the base. The five electrodes are a first current electrode, a second current electrode, a first voltage electrode, a second voltage electrode, and a third voltage electrode. A current supply device and a calculation device are connected to the resistivity sensor.

[0004] The current supply device passes a predetermined current through the first current electrode and the second current electrode and measures the voltage with the first voltage electrode and the second voltage electrode. The calculation device calculates the resistivity of the natural ground from the measured voltage and determines the condition of the natural ground based on this. With this geological exploration device, it is also possible to measure the voltage with the first voltage electrode and the third voltage electrode, or the second voltage electrode and the third voltage electrode.

[0005] Patent Document 2 describes a tunneling machine equipped with a measuring device. The tunneling machine has a cutter, a skin plate, a chamber, an earth removal device, a partition wall, and a measuring device. The cutter has plate-like cutter spokes attached to the front of the cylindrical skin plate and used to excavate the natural ground, and a plate-like member attached to the rear of the cutter spokes. The chamber is a space surrounded by the plate-like member, the partition wall, and the skin plate.

[0006] The measuring device is connected to the plate-shaped member of the cutter. The measuring device rotates within the chamber filled with excavated soil. The measuring device has a rod-shaped member protruding into the chamber and a strain gauge attached to the rod-shaped member. The strain gauge measures the deflection (displacement or deformation) of the rod-shaped member due to the force it receives from the excavated soil in the chamber. The measuring device sends the measurement values ​​measured by the strain gauge to a computer or the like, and the properties of the excavated soil in the chamber are determined based on the measurement values. The degree of soil solidification is also calculated from the measurement values ​​measured by the strain gauge, and blockage of the chamber by soil is detected. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 6902342 [Patent Document 2] Patent No. 4523453 Summary of the Invention [Problem to be solved by the invention]

[0008] However, if the gravel and mud in the soil are not united, separation of the soil may occur. In this case, the gravel may settle relative to the mud. The settling of the gravel may also occur inside the chamber of the shield machine. If the soil separates and the gravel settles relative to the mud, it may cause the shield machine cutter to malfunction.

[0009] It is also known to add mud-adding materials to the excavated soil to make it plastically fluid. This increases the viscosity of the soil, thereby reducing the aforementioned gravel settling. However, if the amount of mud-adding material added is not appropriate for the segregation resistance of the excavated soil, the cost of the mud-adding material may increase or the viscosity of the soil may not be increased sufficiently. Therefore, it is necessary to properly understand the segregation resistance of the soil before adding mud-adding materials.

[0010] An object of the present disclosure is to provide a soil separation resistance measuring device and a soil separation resistance measuring method that can appropriately grasp the soil separation resistance. [Means for solving the problem]

[0011] (1) The soil separation resistance measuring device according to the present disclosure comprises a storage member for storing soil and sand, a vibration member for applying vibrations to the soil and sand stored in the storage member, a resistivity measuring device for measuring a first resistivity value, which is the resistivity value of a first portion of the soil and sand to which vibrations have been applied, and a second resistivity value, which is the resistivity value of a second portion of the soil and sand to which vibrations have been applied, which is different from the first portion, and an evaluation unit for evaluating the separation resistance of the soil and sand from the first resistivity value and the second resistivity value.

[0012] In this soil separation resistance measuring device, soil is contained in a container member, and a vibrating member applies vibrations to the soil contained in the container member. This vibration causes gravel in the soil to settle relative to clay if the soil has low separation resistance. Gravel has a higher resistivity than sand and silt, while clay has a lower resistivity than sand and silt. Therefore, the resistivity measuring device measures a first resistivity value of a first portion of the soil and a second resistivity value of a second portion, thereby estimating the soil type of each of the first and second portions. The evaluation unit then evaluates the separation resistance of the soil from the first and second resistivity values. For example, if the first resistivity value is similar to the second resistivity value, the soil is evaluated as having high separation resistance, whereas if the first resistivity value deviates from the second resistivity value, the soil is evaluated as having low separation resistance. Therefore, by having the evaluation unit evaluate the sedimentation resistance of the soil from the first resistivity value and the second resistivity value, the sedimentation resistance of the soil can be properly determined before adding mud-adding material. Therefore, the amount of mud-adding material to be added can be adjusted according to the sedimentation resistance of the soil. As a result, it is possible to prevent an increase in the cost of mud-adding material and to appropriately increase the viscosity of the soil.

[0013] (2) In the above (1), the vibrating member may vibrate the soil in the vertical direction. In this case, when the soil has low sedimentation resistance, the sediment can be more reliably settled. Therefore, the accuracy of the sedimentation resistance measurement can be improved.

[0014] (3) In the above (1) or (2), the storage member may have a cylindrical portion with an opening and a lid portion that seals the opening. The lid portion may have a metal portion that contacts the soil and an insulator portion that contacts the surface of the metal portion facing away from the soil. The insulator portion may have a through-hole that penetrates the insulator portion and passes a cable extending from the resistivity measuring device through the metal portion. In this case, the soil can be sealed by the lid portion having the metal portion and the insulator portion. Furthermore, by having the insulator portion have a through-hole that passes the cable through the metal portion, the cable can be connected to the metal portion while the top surface of the lid portion is an insulator.

[0015] (4) In any of the above (1) to (3), the storage member may have a cylindrical tubular portion. In this case, the cylindrical portion does not have corners, which prevents soil and sand from concentrating at the corners. This improves the accuracy of the separation resistance measurement. Furthermore, cylindrical tubular portions have the advantage of being easily available.

[0016] (5) In any of the above (1) to (4), the housing member may have a cylindrical portion, and the cylindrical portion may be a PVC pipe. In this case, PVC pipes are easily available, so the housing member can be easily prepared.

[0017] (6) The method for measuring soil separation resistance according to the present disclosure includes the steps of storing soil in a storage member, applying vibrations to the soil stored in the storage member, measuring a first resistivity value, which is the resistivity value of a first portion of the soil to which vibrations have been applied, and a second resistivity value, which is the resistivity value of a second portion different from the first portion of the soil to which vibrations have been applied, and evaluating the separation resistance of the soil from the first resistivity value and the second resistivity value.

[0018] In this soil separation resistance measurement method, a vibrating member applies vibrations to soil contained in a storage member. If the soil has low separation resistance, the vibrations cause the gravel in the soil to settle relative to the clay. Then, by measuring a first resistivity value of a first portion of the soil and a second resistivity value of a second portion, the soil type of each of the first and second portions can be estimated. In the evaluation process, for example, if the first resistivity value is similar to the second resistivity value, the soil is evaluated as having high separation resistance, and if the first resistivity value deviates from the second resistivity value, the soil is evaluated as having low separation resistance. Therefore, by evaluating the separation resistance of the soil from the first and second resistivities, the separation resistance of the soil can be appropriately determined before adding a mud-adding agent. Therefore, similar to the soil separation resistance measurement device, the soil separation resistance measurement method can suppress increases in the cost of mud-adding agents and appropriately increase the viscosity of the soil.

[0019] (7) In the step (6) above, the soil excavated by the shield machine may be stored in the storage member during the process of storing the soil in the storage member. In this case, the segregation resistance of the soil excavated by the shield machine can be properly determined. Therefore, an appropriate amount of mud-adding material can be added to the soil excavated by the shield machine, preventing segregation of the soil and preventing malfunction of the shield machine's cutter. [Effects of the Invention]

[0020] According to the present disclosure, the separation resistance of soil and sand can be appropriately grasped. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a perspective view showing an example of a shield machine. [Figure 2] FIG. 2 is a diagram showing the internal structure of the shield machine of FIG. [Figure 3] 3(a) and 3(b) are diagrams showing the earth and sand inside the chamber of the shield machine. [Figure 4]FIG. 4 is a diagram schematically illustrating the soil separation resistance measuring device according to the embodiment. [Figure 5] Fig. 5(a) is a side view showing a housing member of the soil separation resistance measuring device according to the embodiment, and Fig. 5(b) is a plan view showing the housing member of Fig. 5(a). [Figure 6] FIG. 6 is a cross-sectional view taken along line AA in FIG. 5(a). [Figure 7] FIG. 7 is a cross-sectional view showing the cover of the soil separation resistance measuring device according to the embodiment. [Figure 8] FIG. 8 is a flowchart showing an example of steps of a method for measuring soil separation resistance according to an embodiment. [Figure 9] FIG. 9 is a plan view showing an example of a vibration applying step. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the soil separation resistance measuring device and soil separation resistance measuring method according to the present disclosure will be described with reference to the drawings. In the description of the drawings, identical or corresponding elements are designated by the same reference numerals, and duplicate explanations will be omitted as appropriate. The drawings may be partially simplified or exaggerated for ease of understanding, and the dimensional proportions and the like are not limited to those shown in the drawings.

[0023] FIG. 1 is a perspective view showing a shield machine 1 as an example of a machine for excavating soil G. The shield machine 1 excavates soil G by tunneling through the underground ground. In the ground, for example, construction of a shield tunnel is carried out. The shield machine 1 has a cutter 2 that rotates around an axis L extending in an excavation direction D1, which is the direction in which the shield machine 1 excavates, and a cylindrical skin plate 3 that extends from the cutter 2 in a direction D4 opposite the excavation direction D1 (hereinafter, also referred to as "rearward"). The shield machine 1 performs a shield tunneling method for constructing a tunnel. In the shield tunneling method, the cutter 2 of the shield machine 1 excavates the ground underground, and then segments 5 (lining) are sequentially placed.

[0024] For example, the cutter 2 is a circular cutter disc that rotates in a rotation direction D2 around an axis L. FIG. 2 is a diagram showing the internal structure of the shield machine 1. As shown in FIGS. 1 and 2, the shield machine 1 has a motor 6 that is located behind the cutter 2 and rotates the cutter 2 around the axis L. The motor 6 drives the shaft 2c of the cutter 2, causing the cutter 2 to rotate around the axis L.

[0025] The shield machine 1 has an earth discharge pipe 4 inside the skin plate 3. The earth discharge pipe 4 extends from the cutter 2 into the inside of the skin plate 3. The earth discharge pipe 4 is supplied with earth G, which is the face earth and sand excavated by the cutter 2. The earth discharge pipe 4 discharges the earth and sand G excavated by the cutter 2 to the outside of the shield machine 1.

[0026] The shield machine 1 has, for example, a mud-adding material supply unit 8 that supplies mud-adding material M to the soil G excavated by the cutter 2. The mud-adding material M causes the soil G to plastically fluidize. Adding the mud-adding material M to the soil G increases the viscosity of the soil G. The mud-adding material M includes, for example, a binder and a polymer material. One example of the binder is a bentonite solution. The more mud-adding material M is added, the higher the viscosity of the soil G becomes, and the better the segregation resistance of the soil G becomes.

[0027] For example, the mud-adding material supply unit 8 has a storage unit 8b located inside the skin plate 3, a pipe 8c extending from the storage unit 8b to the cutter 2, and an internal cutter piping 8d extending from the axis L inside the cutter 2 toward the outer periphery of the cutter 2. The cutter 2 has, for example, a shaft 2c, spokes 2d extending radially from the shaft 2c, and a plurality of bits (not shown) formed on the spokes 2d.

[0028] The spokes 2d are made up of a plurality of rod-shaped portions extending from the shaft portion 2c, and a bit is formed in each of the plurality of rod-shaped portions. For example, the cutter internal piping 8d is formed inside one of the plurality of rod-shaped portions. As an example, the cutter internal piping 8d is formed inside a plurality of rod-shaped portions extending in different directions from the shaft portion 2c.

[0029] The storage section 8b stores mud-adding material M. The mud-adding material M stored in the storage section 8b passes through the pipe 8c and the cutter internal piping 8d and is then discharged from the cutter internal piping 8d onto the soil G. For example, the mud-adding material M is supplied forward from the cutter internal piping 8d. The above describes an example of the cutter 2 and the mud-adding material supply section 8. However, the configuration of the cutter 2 and the mud-adding material supply section 8 is not limited to the above example and can be modified as appropriate. The mud-adding material M may be supplied to the soil G in the chamber 7, which will be described later, for example.

[0030] The shield machine 1 has a chamber 7 located in the internal space of the skin plate 3, between the cutter 2 and the discharge pipe 4. The chamber 7 stores earth and sand G excavated by the cutter 2. The earth and sand G stored in the chamber 7 is transported rearward through the inside of the discharge pipe 4.

[0031] 3(a) and 3(b) are diagrams showing the sediment G excavated by the cutter 2 and stored in the chamber 7. FIG. 3(a) shows the sediment G with high separation resistance, and FIG. 3(b) shows the sediment G with low separation resistance. "Separation resistance" is an index that indicates how difficult it is for the sediment G to separate, and is correlated with viscosity. In other words, the higher the viscosity of the sediment G, the higher the separation resistance.

[0032] As shown in Figure 3(a), in the case of soil G with high resistance to separation, the sand and gravel are generally uniform. In contrast, as shown in Figure 3(b), in the case of soil G with low resistance to separation, the soil G may separate in the chamber 7, causing the gravel portion G2 of the soil G to accumulate in the lower part of the chamber 7 and groundwater W to accumulate in the upper part of the chamber 7.

[0033] If gravel G2 settles inside the chamber 7, the cutter 2 rotating at the bottom of the chamber 7 may come into contact with the gravel G2, which may cause the cutter 2 to malfunction. In order to increase the separation resistance of the sediment G, it is effective to add the aforementioned mud-adding material M to the sediment G. However, if the amount of mud-adding material M added is inappropriate, the cost of the mud-adding material M may increase or the separation resistance of the sediment G may not be sufficiently increased. Therefore, it is necessary to be able to appropriately grasp the separation resistance of the sediment G.

[0034] FIG. 4 is a perspective view showing a soil separation resistance measuring device 10 according to this embodiment. The soil separation resistance measuring device 10 measures the separation resistance of soil G. For example, the soil separation resistance measuring device 10 may measure the separation resistance of soil G sampled in advance. For example, the soil separation resistance measuring device 10 may measure the separation resistance of soil G sampled for a boring survey at a site where excavation is scheduled to be performed by a shield machine 1. In this case, the separation resistance of the soil G can be determined in advance before construction work begins.

[0035] The soil separation resistance measuring device 10 may also measure the separation resistance of the soil G in the chamber 7. The soil separation resistance measuring device 10 may also measure the separation resistance of the soil G during construction. That is, the soil separation resistance of the soil G excavated by the cutter 2 may be measured. In this way, the timing when the soil separation resistance measuring device 10 measures the separation resistance of the soil G is not particularly limited.

[0036] The sedimentation resistance measuring device 10 includes a storage member 11 that stores sediment G, a vibrating member 14 that applies vibration V to the sediment G, a resistivity measuring device 15 that measures the resistivity of the sediment G, and an evaluation unit 16 that evaluates the sedimentation resistance of the sediment G from the resistivity value measured by the resistivity measuring device 15. For example, the vibrating member 14 applies vertical vibration V to the sediment G, which causes the sediment G to shake in the vertical direction. "Vertical vibration" means that the vibration is imparted (transmitted) to the sediment G, for example, by the vibrating member itself vibrating in the vertical direction.

[0037] Fig. 5(a) is a side view showing an example of a storage member 11. Fig. 5(b) is a plan view showing an example of a storage member 11. As shown in Figs. 4, 5(a) and 5(b), the storage member 11 has, for example, a tubular portion 12 and a lid portion 13. As an example, the tubular portion 12 is cylindrical.

[0038] The cylindrical portion 12 has openings 12b at one end and the other end in the axial direction A1, which is the direction in which the axis of the cylindrical portion 12 extends. That is, one end and the other end (e.g., the upper end and the lower end) in the axial direction A1 of the cylindrical portion 12 are open. The cylindrical portion 12 is arranged, for example, so that the axial direction A1 coincides with the vertical direction.

[0039] For example, the inner diameter of the cylindrical portion 12 (diameter of the opening 12b) is at least five times the maximum diameter of the gravels of the soil / sand G. In this case, it is possible to conform to the standards of the device for measuring the soil / sand G, and to avoid the problem of variation in measurement results depending on the specifications of the measuring device. For example, when the maximum value of the gravels of the soil / sand G is 25 mm, the inner diameter of the cylindrical portion 12 is 125 mm or more. For example, the inner diameter of the cylindrical portion 12 is greater than 125 mm and not greater than 300 mm (150 mm, for example). By making the inner diameter of the cylindrical portion 12 not greater than 300 mm, the handling properties of the storage member 11 can be improved.

[0040] The cylindrical portion 12 is made of an insulating material (resin, for example). For example, the cylindrical portion 12 is a PVC pipe. In this case, the cylindrical portion 12 is made of vinyl chloride. However, the cylindrical portion 12 may be made of acrylic resin, and the material of the cylindrical portion 12 can be changed as appropriate. The cylindrical portion 12 may or may not be transparent.

[0041] For example, the housing member 11 (as an example, the cylindrical portion 12) has a cable connection portion 17 to which a cable 15c extending from the resistivity measuring device 15 can be connected. Note that, for simplicity, the cable connection portion 17 is not shown in FIG. 4. The cable connection portion 17 protrudes, for example, from the outer surface of the cylindrical portion 12. FIG. 6 is a cross-sectional view taken along line AA in FIG. 5(a). As shown in FIGS. 4, 5(a), 5(b), and 6, the cable connection portion 17 is, for example, a bolt that penetrates the cylindrical portion 12 in the thickness direction of the cylindrical portion 12 (for example, in the radial direction of the cylindrical portion 12).

[0042] For example, the cylindrical portion 12 has a through-hole 12c that penetrates the cylindrical portion 12 in the thickness direction. The cable connection portion 17 is, for example, screwed into the cylindrical portion 12 from the inside, and a portion of the cable connection portion 17 protrudes from the outer surface of the cylindrical portion 12. A portion of the cable connection portion 17 is in contact with the earth and sand G. For example, the bolt head of the cable connection portion 17 is in contact with the earth and sand G.

[0043] For example, a shield clip (not shown) is provided at the end of cable 15c. In this case, cable 15c is connected to cable connecting portion 17 by clamping cable connecting portion 17 between the shield clip.

[0044] For example, the housing member 11 has a plurality of cable connection portions 17. The plurality of cable connection portions 17 are lined up, for example, along the axial direction A1. As an example, the plurality of cable connection portions 17 are lined up at equal intervals along the axial direction A1. In this case, the arrangement interval (pitch) of the cable connection portions 17 lined up along the axial direction A1 is, for example, 5 cm.

[0045] The multiple cable connection parts 17 are lined up, for example, along the circumferential direction A2 of the tubular part 12. As an example, four cable connection parts 17 are lined up along the circumferential direction A2 of the tubular part 12. In this way, by lined up along both the axial direction A1 and the circumferential direction A2, the cable 15c can be connected to any of the cable connection parts 17.

[0046] Fig. 7 is an enlarged cross-sectional view showing the lid portion 13. As shown in Fig. 4 and Fig. 7, the accommodating member 11 has the lid portion 13 that seals the opening 12b of the cylindrical portion 12. The accommodating member 11 has, for example, two lid portions 13. The lid portion 13 is provided at each of one end and the other end of the cylindrical portion 12 in the axial direction A1.

[0047] The lid portion 13 has, for example, a metal portion 13b that contacts the soil G and an insulator portion 13c that contacts a surface 13f of the metal portion 13b that faces away from the soil G. The insulator portion 13c is, for example, plate-shaped. The insulator portion 13c is located outside the accommodating member 11 relative to the metal portion 13b. For example, one of the pair of insulator portions 13c forms the upper end of the accommodating member 11, and the other of the pair of insulator portions 13c forms the lower end of the accommodating member 11.

[0048] The metal portion 13b is, for example, plate-shaped and is located inside the housing member 11 relative to the insulator portion 13c. That is, the metal portion 13b is provided below the insulator portion 13c located at the upper end of the housing member 11 and above the insulator portion 13c located at the lower end of the housing member 11.

[0049] The insulator portion 13c has a through-hole 13d penetrating the insulator portion 13c. The number of through-holes 13d formed in one lid portion 13 is, for example, one. However, the number of through-holes 13d is not particularly limited. As an example, the through-hole 13d is circular. The through-hole 13d is provided to allow a cable 15c extending from the resistivity measuring device 15 to pass through the metal portion 13b.

[0050] Cable 15c has conductor 15d and covering 15f, and conductor 15d of cable 15c passed through through hole 13d is in contact with metal portion 13b, thereby electrically connecting cable 15c to metal portion 13b of lid 13.

[0051] The resistivity measuring device 15 is, for example, an LCR meter. The resistivity measuring device 15 has, for example, a main body 15b and a plurality of cables 15c extending from the main body 15b. The resistivity measuring device 15 has, for example, four cables 15c. In this case, the resistivity measuring device 15 measures the resistivity of the soil G using the four cables 15c.

[0052] Two of the four cables 15c are current supply cables 15c1, and the remaining two are voltage measurement cables 15c2. One of the two current supply cables 15c1 is connected to the metal part 13b that contacts the upper end of the soil G, and the other of the two voltage measurement cables 15c2 is connected to the metal part 13b that contacts the lower end of the soil G.

[0053] For example, the aforementioned shield clip is provided at the end of voltage measurement cable 15c2, and voltage measurement cable 15c2 is connected to cable connection part 17 by clamping cable connection part 17 with the shield clip. The position where voltage measurement cable 15c2 is connected to cable connection part 17 corresponds to measurement position P of resistivity.

[0054] The soil G stored in the storage member 11 has two measurement positions P, a first portion P1 located on the upper side and a second portion P2 located on the lower side. The first portion P1 and the second portion P2 are spaced apart from each other in the vertical direction (axial direction A1). As an example, the second portion P2 is located 5 cm or more and 10 cm or less from the bottom end of the storage member 11, and the first portion P1 is located 20 cm or more and 25 cm or less from the bottom end of the storage member 11. In this case, the distance between the first portion P1 and the second portion P2 is 10 cm or more and 20 cm or less. However, the positions of the first portion P1 and the second portion P2 can be changed as needed.

[0055] The two current supply cables 15c1 apply an AC voltage between the upper and lower ends of the soil G. This causes an AC current to flow through the soil G. At this time, for example, the voltage measurement cable 15c2 measures the potential of the first portion P1, and the resistivity measurement device 15 measures a first resistivity value, which is the resistivity value of the first portion P1.

[0056] Then, the voltage measurement cable 15c2 measures the potential of the second portion P2, and the resistivity measurement device 15 measures the second resistivity value, which is the resistivity value of the second portion P2. In this way, the resistivity measurement device 15 measures the first resistivity value, which is the resistivity value of the first portion P1 of the vibration-applied soil / sand G, and the second resistivity value, which is the resistivity value of the second portion P2, which is different from the first portion P1 of the vibration-applied soil / sand G.

[0057] The vibrating member 14 applies vibration V to the soil G contained in the containing member 11. The vibrating member 14, for example, vibrates the soil G located inside the cylindrical portion 12 from the outside of the cylindrical portion 12 while in contact with the outer surface of the cylindrical portion 12. The vibrating member 14 is, for example, a sander used for polishing. The sander has a vibrating part that moves back and forth in a fixed direction for polishing. The vibrating part of this sander applies vibration V to the soil G while in contact with the outer surface of the cylindrical portion 12. If the vibrating member 14 is a sander, the vibrating member 14 can be one that is easily available.

[0058] For example, the vibration part of the sander is plate-shaped. If the thickness direction of the vibration part of the sander is the Z direction, the direction perpendicular to the Z direction is the X direction, and the direction perpendicular to both the Z direction and the X direction is the Y direction, then for example, the vibration value of the vibration part in the X direction is 331.9 (m / s 2 ), and the vibration value in the Y direction of the vibrating part is 341.6 (m / s 2 ), and the vibration value in the Z direction of the vibrating part was 78.9 (m / s 2) Therefore, if the sander is brought into contact with the outer surface of the cylindrical portion 12 so that the X direction (or Y direction) of the vibrating portion is aligned with the vertical direction (axial direction A1), the vibration V can be effectively applied to the soil and sand G, and the settling of the gravel can be promoted. As a result, the test time can be shortened.

[0059] However, the vibrating member 14 may be something other than a sander. For example, the vibrating member 14 may be an electric sieve. The vibrating member 14 may be a vibration motor. The vibrating member 14 may also be a vibrator. In this way, various types of vibrating members 14 can be used.

[0060] If the sediment G has high resistance to separation, it is difficult to separate even when vibrated, but if its resistance to separation is low, it is easy to separate when vibrated. If the sediment G has low resistance to separation, the gravel portion G2 settles below the containing member 11 relative to the mud portion as a result of the vibration V. Therefore, while the vibrating member 14 is applying the vibration V to the sediment G, the resistivity measuring device 15 measures the first resistivity value of the first portion P1 and the second resistivity value of the second portion P2, thereby enabling the separation resistance of the sediment G to be evaluated.

[0061] That is, if the resistance to separation of the sediment G is high, the sediment G does not separate much even when vibration V is applied to the sediment G, so the first resistivity value is almost the same as the second resistivity value. In contrast, if the resistance to separation of the sediment G is low, the sediment G separates when vibration V is applied to the sediment G, so the difference between the first resistivity value and the second resistivity value becomes larger.

[0062] The evaluation unit 16 evaluates the separation resistance of the sediment G from the first resistivity value and the second resistivity value. For example, the evaluation unit 16 may evaluate the separation resistance of the sediment G by calculating the separation resistance value of the sediment G. For example, the evaluation unit 16 may calculate the separation resistance value as the value obtained by dividing the first resistivity value by the second resistivity value (the ratio of the first resistivity value to the second resistivity value). In this case, the evaluation unit 16 evaluates that the larger the separation resistance value, the higher the separation resistance of the sediment G, and that the smaller the separation resistance value, the lower the separation resistance of the sediment G.

[0063] The evaluation unit 16 may also calculate the difference between the second resistivity value and the first resistivity value as the separation resistance value. In this case, the evaluation unit 16 evaluates that the smaller the separation resistance value, the higher the separation resistance of the sediment G, and determines that the larger the separation resistance value, the lower the separation resistance of the sediment G. In this way, the manner in which the evaluation unit 16 evaluates the separation resistance of the sediment G from the first resistivity value and the second resistivity value can be changed as appropriate.

[0064] The evaluation unit 16 may, for example, calculate the amount of mud-adding material M to be added according to the evaluation of separation resistance. In this case, the evaluation unit 16 calculates a larger amount of mud-adding material M to be added when separation resistance is low compared to when separation resistance is high. The evaluation unit 16 is, for example, a computer. In this case, the first resistivity value and the second resistivity value obtained from the resistivity measuring device 15 are input to the evaluation unit 16, and the evaluation unit 16 evaluates the separation resistance of the soil G from the input first resistivity value and second resistivity value.

[0065] Next, the method for measuring sedimentation resistance according to this embodiment will be described with reference to FIG. 8. FIG. 8 is a flowchart showing an example of steps in a method for measuring the sedimentation resistance of sediment G using the sedimentation resistance measuring device 10. First, sediment G is collected (step S1). For example, sediment G is collected from a site where the shield machine 1 is scheduled to perform excavation. Alternatively, sediment G that has accumulated in the chamber 7 after the shield machine 1 has performed excavation may be collected.

[0066] Next, as shown in Fig. 4, soil G is stored in the storage member 11 (step of storing soil G in the storage member). For example, a lid 13 is attached to one end of the cylindrical portion 12 with the lid 13 facing downward, soil G is placed inside the cylindrical portion 12, and then the lid 13 is attached to the upper end of the cylindrical portion 12. At this time, soil G is stored in the storage member 11 until the cylindrical portion 12 is filled so that the soil G contacts the upper and lower lids 13, and after the soil G has hardened, the lid 13 is attached (step S2).

[0067] As a specific example, soil G is filled into the cylindrical portion 12 to a first height, and the soil G is poked a certain number of times with a ramming rod to harden the soil G. Then, soil G is filled into the cylindrical portion 12 to a second height and rammed a certain number of times with the ramming rod, and then soil G is filled into the cylindrical portion 12 to a third height and rammed a certain number of times with the ramming rod to harden the soil G. As an example, the first height is 10 cm, the second height is 20 cm, the third height is 30 cm, and the above certain number of times is 15. For example, the ramming rod is a round iron bar with a diameter of about 1 cm.

[0068] After the soil G is stored in the storage member 11 as described above, vibration V is applied to the soil G stored in the storage member 11 (a vibration applying step, step S3). For example, as shown in Fig. 9, the soil G inside the storage member 11 is vibrated by bringing a vibrating member 14 into contact with the outer surface of the storage member 11.

[0069] 9, the soil G is vibrated by bringing the vibrating member 14 into contact for a certain period of time with a portion X between a cable connection portion 17 on the outer surface of the housing member 11 and a cable connection portion 17 adjacent to this cable connection portion 17. After the certain period of contact, the vibrating member 14 is moved in the circumferential direction A2 to an adjacent portion X, and the vibrating member 14 is brought into contact with this portion X for a certain period of time.

[0070] As described above, the vibrating member 14 is brought into contact with the portion X for a certain period of time, which is repeated the number of times (four times in the example of FIG. 9 ) that is the number of cable connection portions 17 arranged in the circumferential direction A2. The certain period of time is, for example, 30 seconds. In this case, the time that the vibrating member 14 is in contact with the outer surface of the housing member 11 is two minutes (30 seconds x 4). By bringing the vibrating member 14 into contact with the outer surface of the housing member 11 in this manner, the soil G inside the housing member 11 can be vibrated evenly.

[0071] After vibrating the soil / sand G, the resistivity measuring device 15 measures the resistivity of the soil / sand G (step S4). That is, as shown in Fig. 4, a first resistivity value, which is the resistivity value of a first portion P1 of the soil / sand G to which the vibration V has been applied, and a second resistivity value, which is the resistivity value of a second portion P2 of the soil / sand G to which the vibration V has been applied, are measured (step of measuring resistivity values).

[0072] For example, two current supply cables 15c1 of resistivity measuring device 15 apply an AC voltage to sediment G to pass an AC current through sediment G, and voltage measuring cable 15c2 measures the voltage at first portion P1 to measure a first resistivity value. Then, while the AC current is being passed through sediment G, voltage measuring cable 15c2 measures the voltage at second portion P2 to measure a second resistivity value.

[0073] The evaluation unit 16 then evaluates the separation resistance of the sediment G from the first resistivity value and the second resistivity value (evaluation step, step S5). For example, the evaluation unit 16 calculates the ratio of the first resistivity value of the first portion P1 to the second resistivity value of the second portion P2 as the separation resistance value. For example, the evaluation unit 16 evaluates the separation resistance of the sediment G as high when the separation resistance value is equal to or greater than a certain value, and evaluates the separation resistance of the sediment G as low when the separation resistance is less than the certain value. For example, when the separation resistance is evaluated as high, the amount of mud-adding material M added is reduced compared to when the separation resistance is evaluated as low. After the evaluation unit 16 evaluates the separation resistance as described above, the series of steps in the sediment separation resistance measurement method are completed.

[0074] Next, the effects obtained from the sedimentation resistance measurement device 10 and sedimentation resistance measurement method according to this embodiment will be described. In the sedimentation resistance measurement device 10 and sedimentation resistance measurement method according to this embodiment, sediment G is contained in a container 11, and a vibrating member 14 applies vibration V to the sediment G contained in the container 11. If the sedimentation resistance of the sediment G is low due to the vibration V, the gravel in the sediment G will settle relative to the clay. Among the sediment G, gravel has a higher resistivity than sand and silt, and clay has a lower resistivity than sand and silt. Therefore, by using the resistivity measurement device 15 to measure the first resistivity value of the first portion P1 and the second resistivity value of the second portion P2 of the sediment G, the type of soil in each of the first portion P1 and the second portion P2 can be estimated.

[0075] The evaluation unit 16 then evaluates the separation resistance of the sediment G from the first resistivity value and the second resistivity value. For example, if the first resistivity value is similar to the second resistivity value, the separation resistance of the sediment G is evaluated as high, and if the first resistivity value deviates from the second resistivity value, the separation resistance of the sediment G is evaluated as low. Therefore, by having the evaluation unit 16 evaluate the separation resistance of the sediment G from the first resistivity value and the second resistivity value, the separation resistance of the sediment G can be appropriately determined before adding the mud-adding material M. Therefore, the amount of mud-adding material M to be added can be adjusted according to the separation resistance of the sediment G. As a result, the cost of the mud-adding material M can be prevented from increasing and the viscosity of the sediment G can be appropriately increased.

[0076] As described above, the vibrating member 14 may apply vibration V in the vertical direction (axial direction A1) to the soil G. In this case, when the sedimentation resistance of the soil G is low, the gravel can be more reliably settled. Therefore, the accuracy of the measurement of the sedimentation resistance can be improved.

[0077] As shown in FIGS. 4 and 7 , the housing member 11 may include a cylindrical portion 12 having an opening 12b and a lid portion 13 that seals the opening 12b. The lid portion 13 may include a metal portion 13b that contacts the sediment G and an insulator portion 13c that contacts a surface 13f of the metal portion 13b facing away from the sediment G. The insulator portion 13c may include a through-hole 13d that penetrates the insulator portion 13c and allows a cable 15c extending from the main body 15b of the resistivity measuring device 15 to pass through the metal portion 13b. In this case, the sediment G can be sealed by the lid portion 13 having the metal portion 13b and the insulator portion 13c. Furthermore, since the insulator portion 13c has the through-hole 13d that allows the cable 15c to pass through the metal portion 13b, the cable 15c can be connected to the metal portion 13b while the top surface of the lid portion 13 is an insulator.

[0078] The storage member 11 may have a cylindrical tubular portion 12. In this case, the cylindrical portion 12 does not have corners, which prevents the soil G from concentrating at the corners. This improves the accuracy of the separation resistance measurement. Another advantage is that the cylindrical portion 12 is easily available.

[0079] As described above, the housing member 11 may have the cylindrical portion 12, and the cylindrical portion 12 may be a PVC pipe. In this case, since PVC pipes are easily available, the housing member 11 can be easily prepared.

[0080] As described above, in the soil separation resistance measuring method, in the step of storing the soil G in the storage member 11, the soil G excavated by the shield machine 1 may be stored in the storage member 11. In this case, it is possible to properly grasp the separation resistance of the soil G excavated by the shield machine 1. Therefore, an appropriate amount of mud-adding material M can be added to the soil G excavated by the shield machine 1, which prevents the soil G from separating and prevents malfunction of the cutter 2 of the shield machine 1.

[0081] Next, an example using the sediment separation resistance measuring device 10 will be described. Note that the sediment separation resistance measuring device and sediment separation resistance measuring method according to the present disclosure are not limited to the following example. In the example, an experiment was carried out using the sediment separation resistance measuring device 10. Soil G was used as simulated soil with a high gravel content, and a bentonite solution (binder) and a polymer material were added to the simulated soil as a mud-adding material M. The concentration of the bentonite solution was 70 kg / m 3 The injection rate was set at 35%. The amount of polymer added was 1 ml of bentonite solution. 3 The weights were set to 4 kg (Example 1), 8 kg (Example 2), and 12 kg (Example 3). A mini-slump test, a table flow test, and a feeler test were performed on Examples 1 to 3, and the first resistivity value of the first portion P1 and the second resistivity value of the second portion P2 were obtained to evaluate separation resistance.

[0082] The mini-slump test was conducted in accordance with "JIS R 5201:1997 Physical Testing Methods for Cement" and "JIS A 1171:2000 Testing Methods for Polymer-Cement Mortar." In the mini-slump test, the simulated soil from Examples 1 to 3 was packed into a mini-slump cone and poked with a ram. The opening of the mini-slump cone was then pointed downward to measure the drop in height of the simulated soil ejected from the mini-slump cone. The results were 8.2 cm for Example 1, 7.8 cm for Example 2, and 4.0 cm for Example 3.

[0083] The table flow test was conducted in accordance with "12 Flow Test 12.2 Flow Value Characteristics" of JIS R 5201:2015 (Physical Testing Methods for Cement). In the table flow test, the simulated soils of Examples 1 to 3 were packed in two layers into a flow cone placed on a flow table, and the simulated soils were poked 15 times with a ram. After leveling the surface of the simulated soil, the flow cone was removed vertically. The simulated soil was then subjected to 15 dropping motions, and the maximum diameter and the diameter perpendicular to the maximum diameter were measured after the simulated soil spread. The average of these measurements was used as the table flow value. The results were 193 × 189 (mm) for Example 1, 175 × 170 (mm) for Example 2, and 138 × 126 (mm) for Example 3.

[0084] In the touch test, the ease of separation of the simulated soils of Examples 1 to 3 was measured by hand by grasping each sample in the hand. As a result, the simulated soil of Example 1 separated the best, the simulated soil of Example 2 separated the second best, and the simulated soil of Example 3 separated the least.

[0085] In the simulated soil of Example 1, the first resistivity value was 24 (Ω·m), the second resistivity value was 47 (Ω·m), and the ratio of the first resistivity value to the second resistivity value was 51%. In the simulated soil of Example 2, the first resistivity value was 26 (Ω·m), the second resistivity value was 43 (Ω·m), and the ratio of the first resistivity value to the second resistivity value was 60%. In the simulated soil of Example 3, the first resistivity value was 27 (Ω·m), the second resistivity value was 31 (Ω·m), and the ratio of the first resistivity value to the second resistivity value was 87%. From the above, the above ratios were highest in Example 1, second highest in Example 2, and lowest in Example 3. Therefore, it was found that the simulated soil of Example 3 had the highest separation resistance, the simulated soil of Example 2 had the second highest separation resistance, and the simulated soil of Example 1 had the lowest separation resistance.

[0086] The above describes embodiments and examples of the sediment separation resistance measurement device and sediment separation resistance measurement method according to the present disclosure. However, the sediment separation resistance measurement device and sediment separation resistance measurement method according to the present disclosure are not limited to the above embodiments or examples, and may be further modified within the scope of the gist described in the claims. In other words, the function, shape, size, material, number, and arrangement of each part of the sediment separation resistance measurement device according to the present disclosure, as well as the content and order of the steps of the sediment separation resistance measurement method, can be appropriately changed within the scope of the above gist.

[0087] For example, in the above-described embodiment, an example was described in which the amount of mud-adding material M to be added was changed depending on the separation resistance of the soil and sand G. However, the type of mud-adding material M to be added may be changed depending on the separation resistance of the soil and sand G.

[0088] In the above-described embodiment, as shown in Fig. 9, an example has been described in which the vibrating member 14 is brought into contact with a portion X between two cable connection portions 17 for a certain period of time to vibrate the soil G, and then the vibrating member 14 is moved to an adjacent portion X in the circumferential direction A2. However, the soil G may also be vibrated by bringing multiple vibrating members 14 into contact with multiple portions X simultaneously. In this case, the time required to vibrate the soil G can be shortened.

[0089] In the above-described embodiment, an example has been described in which the evaluation unit 16 evaluates the separation resistance of the sediment G from the ratio of the first resistivity value to the second resistivity value. However, the evaluation unit 16 may evaluate the separation resistance of the sediment G from the difference between the second resistivity value and the first resistivity value. In this way, the method of evaluating the separation resistance of the sediment G using the first resistivity value and the second resistivity value can be changed as appropriate. [Explanation of symbols]

[0090] 1...Shield machine, 2...Cutter, 2c...Shaft, 2d...Spoke, 3...Skin plate, 4...Soil discharge pipe, 5...Segment, 6...Motor, 7...Chamber, 8...Slurry supply unit, 8b...Storage unit, 8c...Pipe, 8d...Cutter internal piping, 10...Sediment separation resistance measuring device, 11...Storage member, 12...Cylindrical part, 12b...Opening, 12c...Through-hole, 13...Cover part, 13b...Metal part, 13c...Insulator part, 13d...Through-hole, 13f...Surface, 14... Vibrating member, 15...resistivity measuring device, 15c...cable, 15c1...current supply cable, 15c2...voltage measuring cable, 15d...conductor part, 15f...coating part, 16...evaluation part, 17...cable connection part, A1...axial direction, A2...circumferential direction, D1...excavation direction, D2...rotation direction, D4...opposite direction, G...soil, G2...gravel, L...axial line, M...mud adding material, P...measurement position, P1...first part, P2...second part, V...vibration, W...groundwater, X...part.

Claims

1. a storage member for storing soil and sand; a vibration member that applies vibration to the soil and sand contained in the container; a resistivity measuring device that measures a first resistivity value, which is the resistivity value of a first portion of the soil to which the vibration has been applied, and a second resistivity value, which is the resistivity value of a second portion of the soil to which the vibration has been applied, which is different from the first portion; an evaluation unit that evaluates separation resistance of the soil and sand from the first resistivity value and the second resistivity value; Equipped with Sediment separation resistance measuring device.

2. The vibration member applies vibration to the soil in a vertical direction. The soil separation resistance measuring device according to claim 1 .

3. the housing member has a cylindrical portion having an opening and a lid portion that seals the opening, The lid portion has a metal portion that contacts the soil and sand, and an insulator portion that contacts a surface of the metal portion that faces away from the soil and sand, the insulator portion has a through hole that penetrates the insulator portion and allows a cable extending from the resistivity measuring device to pass through the metal portion; The soil separation resistance measuring device according to claim 1 or 2.

4. The housing member has a cylindrical portion. The soil separation resistance measuring device according to claim 1 or 2.

5. The housing member has a cylindrical portion, and the cylindrical portion is a PVC pipe. The soil separation resistance measuring device according to claim 1 or 2.

6. storing the soil in a storage member; applying vibration to the soil and sand contained in the containing member; measuring a first resistivity value, which is the resistivity value of a first portion of the soil to which the vibration has been applied, and a second resistivity value, which is the resistivity value of a second portion of the soil to which the vibration has been applied, which is different from the first portion; evaluating the separation resistance of the soil and sand from the first resistivity value and the second resistivity value; Equipped with Method for measuring soil separation resistance.

7. In the step of storing the soil in a storage member, the soil excavated by the shield machine is stored in the storage member. The method for measuring soil separation resistance according to claim 6.

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