JP7762091B2 - Testing device for plastic flow properties of specimens under pressure in a shield machine chamber - Google Patents

Description

The present invention relates to a device for testing the plastic fluidity of samples under chamber pressure in a shield machine, and more specifically to a device for conducting plastic fluidity tests under chamber pressure on excavated soil (samples) taken into the cutter chamber (hereinafter referred to as the chamber) of an earth pressure shield machine.

The earth pressure shield method is a construction method that uses a closed shield machine, in which the excavated soil is taken into a chamber using a cutter head and filled therein to stabilize the tunnel face. There are two types of earth pressure shield methods: earth pressure shield method and muddy earth pressure shield method. The earth pressure shield method collects the soil at the tunnel face into a chamber, adjusts the pressure using a screw conveyor that discharges the soil, and stabilizes the tunnel face by maintaining a balance between the excavated soil taken into the chamber and the earth pressure at the tunnel face. The muddy earth pressure shield method adds water, muddy water, additives, air bubbles, etc. to the excavated soil and stirs it to plastically fluidize it, which is then collected into the chamber to stabilize the tunnel face.

In the earth pressure shield tunneling method, in order to maintain the earth pressure necessary to stabilize the tunnel face and discharge the appropriate amount of soil as the shield machine excavates, the excavated soil taken into the chamber must have appropriate plastic fluidity and be waterproof to prevent groundwater from flowing into the chamber.

The properties of the excavated soil in the chamber have a significant impact on the stability of the tunnel face as the shield machine excavates, so it is necessary to properly understand the properties of the excavated soil. Various technologies for understanding the properties of excavated soil have been disclosed in the past for earth pressure shield tunneling methods (see, for example, Patent Documents 1 and 2).

The technology described in Patent Document 1 (Japanese Patent No. 6416496) relates to a method for measuring and evaluating the properties of excavated soil inside a chamber used in earth pressure shield tunneling. This method for measuring and evaluating the properties of excavated soil inside a chamber involves installing an earth pressure meter, shear force meter, or shear strain meter on the inner surface of the chamber, the surfaces of the mixing blades and fixed blades, and the back surface of the cutter facing the chamber, respectively, to measure the pressure, shear force, or shear strain acting on the inner surface of the chamber, the surfaces of the mixing blades and fixed blades, and the back surface of the cutter.

Patent Document 2 (Patent Publication No. 6522954) describes a method for measuring and evaluating the properties of excavated soil inside a chamber used in earth pressure shield tunneling. This method for measuring and evaluating the properties of excavated soil inside a chamber used in earth pressure shield tunneling uses an earth pressure meter and a shear force meter to measure the pressure and shear force acting on various parts of the chamber from the mud, and evaluates the properties of the mud inside the chamber based on these measurements. Earth pressure meter and shear force meter are installed on the inner surface of the chamber, the surfaces of the mixing blades and fixed blades, and the back surface of the cutter facing the chamber, respectively, to measure the pressure and shear force acting on the inner surface of the chamber, the surfaces of the mixing blades and fixed blades, and the back surface of the cutter. The shear force meter is housed in a case.

Patent No. 6416496 Patent No. 6522954

The technologies described in Patent Documents 1 and 2 involve installing measuring instruments such as soil pressure gauges, shear force gauges, and shear strain gauges on the inner surface of the chamber, the surfaces of the stirring blades and fixed blades, and the back surface of the cutter facing the chamber. The measuring instruments are directly attached to the equipment inside the chamber. Such measuring instruments require regular maintenance and must be repaired or replaced if they break down.

However, with the technologies described in Patent Documents 1 and 2, the measuring equipment is directly attached to the equipment inside the chamber, making maintenance and replacement time-consuming and, in the worst case, impossible. This means that it is not possible to measure the force acting on various parts of the chamber from the mud and reliably evaluate the properties of the mud inside the chamber based on these measurements. Furthermore, even if the shear force meter is housed in a case, the case is installed inside the chamber, so the above-mentioned inconveniences cannot be resolved.

To address this issue, one possible solution is to collect the excavated soil from the chamber through a partition wall into a capsule, and then use the collected excavated soil (sample) to test its properties (plastic fluidity). However, if the mud-adding material is bubbly, releasing the collected excavated soil into the capsule will cause the bubbles to expand and burst due to the pressure difference, changing the properties of the excavated soil (sample). Even if the mud-adding material is not bubbly, it is preferable to test the collected excavated soil to be used as a sample under the same pressure as in the chamber. In particular, during shield excavation at great depths, the pressure of the bubbles becomes high, so testing the properties of the sample at atmospheric pressure will result in the test being performed on a sample with different properties than in the chamber.

The present invention has been proposed in consideration of the above-mentioned circumstances, and aims to provide a plastic fluidity testing device for performing plastic fluidity tests on excavated soil (sample) taken into the chamber of an earth pressure shield machine under pressure within the chamber.

The plastic fluidity testing device for samples under chamber pressure in a shield machine of the present invention is a device for conducting plastic fluidity testing under chamber pressure on excavated soil (sample) taken into the chamber of an earth pressure shield machine.

The device for testing the plastic flow properties of samples under chamber pressure in a shield machine according to the present invention is a device for performing a plastic flow property test on excavated soil taken into a shield machine equipped with a sample recovery section that is connected to the chamber of the shield machine, under the chamber pressure, by installing a test site in the sample recovery section that is connected to the chamber, and performing a plastic flow property test on the recovered sample in the sample recovery section while the pressure remains the same as the chamber pressure. The sample recovery section is not located inside the chamber, and the excavated soil is recovered from an opening in the chamber partition.

In the above-described plastic flowability testing device, a first ball valve that functions as an opening/closing means can be provided. The first ball valve that functions as the opening/closing means can be provided between the opening and the sample recovery section.

A specific plastic flowability test apparatus can be configured to include a rotating body rotatably attached to a sample collection section, a plurality of vanes axially protruding at equal intervals in the circumferential direction from the inner peripheral surface of the rotating body, a rotation drive device that rotates the rotating body, and a rotation resistance measurement device that measures the rotation resistance of the vanes. In this type of plastic flowability test apparatus, the plastic flowability of the sample is determined based on the rotation resistance value measured by the rotation resistance measurement device.

Furthermore, a specific plastic fluidity test apparatus can be configured to include a penetration rod capable of penetrating into the sample recovery section, a penetration device for penetrating the penetration rod into the sample recovery section, and a penetration resistance measuring device for measuring the penetration resistance value of the penetration rod. In this type of plastic fluidity test apparatus, the plastic fluidity of the sample is determined based on the penetration resistance value measured by the penetration resistance measuring device.

Furthermore, a specific plastic flowability test apparatus can be configured such that the sample collection section includes a shear box that can be moved in a direction perpendicular to the sample intake direction, a movement device that moves the shear box, a movement resistance measurement device that measures the movement resistance of the shear box, and a movement displacement measurement device that measures the movement displacement of the shear box. In this type of plastic flowability test apparatus, the plastic flowability of the sample is determined based on the measurements of the movement resistance measurement device and the movement displacement measurement device.

Furthermore, a specific plastic flowability test apparatus can be configured to include a capsule attached to a sample collection unit, a capsule weight measuring device that measures the weight of the capsule during the process of taking the sample into the capsule, and a sample intake time measuring device that measures the time until the capsule is filled with sample. In this type of plastic flowability test apparatus, the plastic flowability of the sample is determined based on the capsule weight measured by the capsule weight measuring device and the sample intake time measured by the sample intake time measuring device.

Furthermore, a specific plastic flowability test apparatus can be configured to include a capsule attached to a sample collection unit, a resistor installed in the capsule, a resistor movement device that moves the resistor within the capsule, and a movement resistance measurement device that measures the movement resistance of the resistor. In this type of plastic flowability test apparatus, the plastic flowability of the sample is determined based on the movement resistance value measured by the movement resistance measurement device.

Furthermore, a specific plastic flowability test apparatus can be configured to include a capsule attached to a sample collection unit, a vibrator housed in the capsule, a vibration device that vibrates the vibrator, and an accelerometer that measures the acceleration when the vibrator is vibrated. In this type of plastic flowability test apparatus, the plastic flowability of the sample is determined based on changes in the amplitude and frequency of the vibrator measured by the accelerometer.

Furthermore, a specific plastic flowability test apparatus can be configured to include a capsule attached to a sample collection unit, a vibrator housed in the capsule, a drive power supply control unit for controlling the supply of drive power to electromagnetically vibrate the vibrator, and a vibration amplitude measurement unit for measuring the vibration amplitude value of the vibrator. In this type of plastic flowability test apparatus, the plastic flowability of the sample is determined based on the vibration amplitude value measured by the vibration amplitude measurement unit or the drive power value in the drive power supply control unit when the vibrator is vibrated at a predetermined vibration amplitude.

In the plastic fluidity test device for a sample under chamber pressure in a shield machine according to the present invention, the test portion of the plastic fluidity test device is installed in a sample recovery section that is connected to the chamber.

In other words, since the test portion of the plastic fluidity test device is installed in a sample collection section that is connected to the chamber, maintenance and replacement of the plastic fluidity test device can be performed more easily than when the plastic fluidity test device is directly attached to a device located within the chamber.

Since the plastic flow test is performed on the excavated soil (sample) taken into the chamber under the pressure within the chamber, it is possible to perform the test on a sample with the same properties as those inside the chamber.

FIG. 1 is a longitudinal cross-sectional view of a shield machine showing the position of an in-chamber sample recovery device to which a plastic flowability test device according to an embodiment of the present invention is applied. FIG. 1 is an explanatory diagram of an in-chamber sample recovery device to which a plastic flowability test device according to an embodiment of the present invention is applied. 1 is a schematic diagram showing an example (1) of a plastic flowability test device according to an embodiment of the present invention. FIG. FIG. 1 is a schematic diagram showing Example (2) of a plastic flowability test device according to an embodiment of the present invention. FIG. 1 is a schematic diagram showing an example (3) of a plastic flowability test device according to an embodiment of the present invention. FIG. 1 is a schematic diagram showing Example (4) of a plastic flowability test device according to an embodiment of the present invention. FIG. 10 is a schematic diagram showing an example (5) of a plastic flowability test device according to an embodiment of the present invention. FIG. 10 is a schematic diagram showing an example (6) of a plastic flowability test device according to an embodiment of the present invention. FIG. 10 is a schematic diagram showing an example (7) of a plastic flowability test device according to an embodiment of the present invention. FIG. 10 is a schematic diagram showing an example (8) of a plastic flowability test device according to an embodiment of the present invention. FIG. 10 is a schematic diagram showing an example (9) of a plastic flowability test device according to an embodiment of the present invention. 1 is a schematic diagram showing an example (10) of a plastic flowability test device according to an embodiment of the present invention. FIG. 11 is a schematic diagram showing an example (11) of a plastic flowability test device according to an embodiment of the present invention. 1 is a flowchart showing an outline of a plastic flowability testing method according to an embodiment of the present invention.

Hereinafter, with reference to the drawings, a plastic flow test device for a sample under chamber pressure in a shield machine according to an embodiment of the present invention (hereinafter sometimes abbreviated as plastic flow test device ) will be described.

Figures 1 to 13 illustrate a plastic fluidity testing device according to an embodiment of the present invention. Figure 1 is a longitudinal cross-sectional view of a shield machine showing the location of an in-chamber sample recovery device. Figure 2 is an explanatory diagram of the in-chamber sample recovery device. Figures 3 to 13 are schematic diagrams showing examples of the plastic fluidity testing device. Figure 14 is a flowchart showing the steps of a plastic fluidity testing method using the plastic fluidity testing device according to an embodiment of the present invention. Note that the front side of the shield machine, as viewed in the direction of excavation, may be referred to as the front side in the excavation direction, the cutter head side, or the natural ground side. The rear side of the shield machine, as viewed in the direction of excavation, may be referred to as the rear side in the excavation direction, the tail side, or the inside of the shield machine.

<Features of the plastic flow test equipment>
The plastic fluidity test device according to an embodiment of the present invention is a device for conducting a plastic fluidity test on a sample under the pressure inside the chamber of a shield machine, and is characterized in that the plastic fluidity test on the sample is conducted under the pressure inside the chamber using an in-chamber sample recovery device for recovering the sample from inside the chamber. Note that the use of the in-chamber sample recovery device is a concept that includes not only the use of the in-chamber sample recovery device itself, but also the use of some of the components that make up the in-chamber sample recovery device.

<Outline of the sample recovery device>
The in-chamber sample recovery device 70 to which the plastic fluidity testing device according to an embodiment of the present invention is applied is a device for recovering samples from the chamber 10 in an earth pressure shield tunneling method in order to analyze the properties of excavated soil in the chamber over the entire tunnel cross section, and is particularly suitable for use with shield machines with large cross sections exceeding 10 m in diameter. The earth pressure shield tunneling method to which the present invention is applied is particularly suitable for the mud earth pressure shield tunneling method and the air bubble shield tunneling method. Furthermore, the in-chamber sample recovery device 70 according to an embodiment of the present invention is equipped with a mechanism for expelling air trapped in the upper part of the chamber 10.

As shown in Figures 1 and 2, this intra-chamber sample recovery device 70 comprises openings 30 provided in the chamber partition 20 of the shield machine, and sample recovery means 40 connected to each opening 30. The openings 30 are openings for recovering excavated soil taken into the chamber 10, and are provided in multiple locations, including at least the upper part of the chamber partition 20. The sample recovery means 40 is connected in communication with the openings 30 and is a device for recovering excavated soil taken into the chamber 10 via the openings 30.

<Opening>
The openings 30 are provided so as to penetrate the chamber partition wall 20, and although not shown, are provided in a total of four locations, for example, at the top, left and right sides, and near the center of the chamber partition wall 20.

As shown in Figures 1 and 2, an attachment opening 31 is provided in the chamber partition wall 20, and a blocking plate 32 for blocking the attachment opening 31 is attached to the inside of the shield machine side of the attachment opening 31, keeping the attachment opening 31 normally closed. A recovery pipe 41 is attached to the center of the blocking plate 32, passing through the blocking plate 32.

A recovery pipe support member 33 is attached to the mounting opening 31, closer to the chamber 10 than the closing plate 32 and approximately flush with the chamber partition wall 20. The recovery pipe support member 33 substantially blocks the mounting opening 31 and is connected to the front end of the recovery pipe 41. The front end of the recovery pipe 41 is connected to the mounting opening 31. The recovery pipe 41 functions as part of the sample recovery means 40.

In the example described above, the mounting opening 31, recovery pipe support member 33, and closure plate 32 function as the opening 30. These components are provided to reinforce the chamber partition 20 and recovery pipe 41, as well as to facilitate maintenance. As shown in Figures 1 and 2, the mounting opening 31 is opened in the chamber partition 20, and the intra-chamber sample recovery device 70 is attached using a closure plate 32 or the like. However, the front end of the recovery pipe 41 may be directly connected to the mounting opening 31 provided in the chamber partition 20 without using a closure plate 32 or the like.

<Opening/Closing Means>
As shown in Figure 2, a first ball valve 42 that functions as an opening opening/closing means is attached to the recovery pipe 41 so as to be located on the opening 30 side of the sample recovery means 40. The first ball valve 42 shown in Figure 2 is electrically operated, but it may also be manually operated.

The chamber 10 is filled with excavated soil in a plastic flow state, and pressure is applied to stabilize the face. The pressure inside the chamber 10 varies depending on the properties of the excavated soil, but if the chamber 10 and the recovery pipe 41 are connected, a so-called eruption phenomenon may occur, and the excavated soil may blow out from the joints of the recovery pipe 41 or the sample recovery capsule 44.

For this reason, it is preferable that the first ball valve 42 in this embodiment be an electrically operated valve with an adjustable opening. In other words, by gradually opening the first ball valve 42 rather than opening it all at once, it is possible to prevent the occurrence of an eruptive phenomenon.

As shown in Figure 2, an emergency ball valve 43 is attached to the recovery pipe 41 closer to the closure plate 32 than the first ball valve 42. This emergency ball valve 43 is manually operated and is normally open. In the event of an emergency stop of sample recovery, the opening/closing handle 43a is operated to close the valve. In this embodiment, the first ball valve 42 is the main component of the opening opening/closing means, but the emergency ball valve 43 is also an auxiliary component of the opening opening/closing means.

<Sample collection means>
2, sample recovery means 40 is connected midway along recovery pipe 41. This sample recovery means 40 consists of a cylindrical sample recovery capsule 44 and a pair of pipe joints 45 for attaching and detaching sample recovery capsule 44 to recovery pipe 41. Pipe joints 45 are housing-type joints for connecting adjacent pipe members, and can be attached to the outer periphery of the joint between recovery pipe 41 and sample recovery capsule 44 and fastened with bolts and nuts to connect recovery pipe 41 and sample recovery capsule 44 in series.

In other words, the recovery pipe 41 is divided into a front section and a rear section, with the sample recovery capsule 44 sandwiched between them. The front end of the sample recovery capsule 44 is attached to the rear end of the front section of the recovery pipe 41 using a pipe joint 45, and the rear end of the sample recovery capsule 44 is attached to the front end of the rear section of the recovery pipe 41 using a pipe joint 45.

<Sample recovery capsule>
As described above, the sample recovery capsule 44 is a cylindrical member and is detachable from the recovery pipe 41. Therefore, a desired amount of sample can be recovered by replacing the sample recovery capsule 44. The plastic flowability test apparatus according to the present invention utilizes an in-chamber sample recovery device 70 to perform a plastic flowability test on a sample under chamber pressure. The shape of the in-chamber sample recovery device 70 for performing a plastic flowability test on a sample under chamber pressure may differ from that shown in the drawings.

<Communication opening/closing means>
In this embodiment, a testing device may be used that performs a plastic flow test on a sample by recovering the sample into the sample recovery capsule 44 via the recovery pipe 41. In this case, the front end of the recovery pipe 41 and the rear end of the sample recovery capsule 44 must be open in order to introduce the sample into the sample recovery capsule 44. That is, if the front end of the recovery pipe 41 is closed, the sample will not flow in from the chamber 10, and if the rear end of the sample recovery capsule 44 is closed, the pressure inside the sample recovery capsule 44 will increase and the sample will not flow in. For this reason, this embodiment is provided with a communication opening/closing means that opens and closes the rear end of the sample recovery means 40 (sample recovery capsule 44) to switch between a connected recovery state in which the sample in the chamber 10 can be recovered and a connected closed state in which the sample in the chamber 10 cannot be recovered.

This communication opening/closing means consists of an air vent ball valve 52 that functions as the air vent means 50, or a second ball valve 60 attached to the recovery pipe 41 located at the rear end of the sample recovery means 40 (sample recovery capsule 44). In the example shown in Figure 2, the second ball valve 60 attached to the recovery pipe 41 located at the rear end of the sample recovery means 40 (sample recovery capsule 44) is manual, but it may also be electrically operated.

In this embodiment, the air vent means 50 (air vent ball valve 52) also functions as the communication opening/closing means, but the second ball valve 60 provided at the rear end of the recovery pipe 41 may also function as the communication opening/closing means.

<Outline of plastic flow test equipment>
The plastic flow test apparatus according to an embodiment of the present invention is configured with a sample recovery unit 300 or an apparatus for measuring the plastic flow properties of a sample in the chamber 10 via the sample recovery unit 300. Note that the sample recovery unit 300 in the embodiment of the present invention refers to a group of devices installed on the tail side, including the sample recovery capsule 44 provided in the intra-chamber sample recovery device 70, or a group of devices that can replace these, and does not necessarily refer only to devices similar to the sample recovery capsule 44 provided in the intra-chamber sample recovery device 70. Specific examples of the plastic flow test apparatus will be described below.

<Plastic flowability test device (1)>
The first embodiment of the plastic fluidity test apparatus 110 is an example using a vane shear test apparatus, as shown in Figure 3. This plastic fluidity test apparatus 110 includes a rotating shaft 111 installed in a sample recovery capsule 44 installed in the sample recovery section 300, a plurality of vanes 112 axially arranged at equal intervals in the circumferential direction on the outer circumferential surface of the rotating shaft 111, a rotational drive device 113 that rotates the rotating shaft 111, and a rotational resistance measurement device 114 that measures the rotational resistance of the vanes 112. The first embodiment of the plastic fluidity test apparatus 110 is a test apparatus conforming to the "in situ vane shear test" specified in the Geotechnical Society Standard: JGS 1411. The rotating shaft 111 with the vanes 112 is installed in the sample recovery capsule 44, and the rotational drive device 113 and the rotational resistance measurement device 114 are installed at the rear (tail side) of the sample recovery capsule 44.

In the first embodiment of the plastic flowability testing device 110, a rotating shaft 111 having multiple vanes 112 is installed inside the sample recovery capsule 44. Once the sample recovery capsule 44 is filled with sample, the rotating shaft 111 is rotated by the rotary drive device 113, and the shear resistance of the sample is applied to the multiple vanes 112. The plastic flowability (shear resistance) of the sample can then be determined based on the rotational resistance value measured by the rotational resistance measuring device 114. Furthermore, by electrically connecting the rotational resistance measuring device 114 to a personal computer, the measurement data can be imported into the personal computer.

The rotational drive device 113 consists, for example, of an electric motor for rotating the rotating shaft 111 and an auxiliary device for transmitting the rotational force of the electric motor to the rotating shaft 111. Alternatively, a mechanism for manually rotating the rotating shaft 111 may be used. The rotational resistance measurement device 114 consists, for example, of a torque meter for measuring the rotational torque of the rotating shaft 111.

<Plastic flowability test device (2)>
As shown in Fig. 4, the plastic flowability test apparatus 120 of the second embodiment is a test apparatus in which the vane 122 is installed at a different position compared to the plastic flowability test apparatus 110 of the first embodiment. In this plastic flowability test apparatus 120, a rotating shaft 121 is used that penetrates the chamber partition (bulkhead) 20, so that the rotating shaft 121 protrudes into the chamber 10. The vane 122 is installed on the outer peripheral surface of the rotating shaft 121 that protrudes into the chamber 10.

The other configuration is substantially the same as that of the plastic flowability test apparatus 110 of the first embodiment. A rotating shaft 121 having a plurality of vanes 122 is installed in the chamber 10 via the sample collection unit 300. When the rotating shaft 121 is rotated by the rotation drive device 123 with the chamber 10 filled with a sample, the shear resistance of the sample is applied to the plurality of vanes 122. The plastic flowability (shear resistance) of the sample in the chamber 10 can then be determined based on the rotational resistance value measured by the rotational resistance measurement device 124. Note that when conducting a plastic flowability test on a sample, the rotating shaft 121 having a plurality of vanes 122 is temporarily installed in the chamber 10; the rotating shaft 121 having a plurality of vanes 122 is not permanently installed in the chamber 10.

The rotational drive device 123 comprises, for example, an electric motor for rotating the rotating shaft 121 and an auxiliary device for transmitting the rotational force of the electric motor to the rotating shaft 121. Alternatively, a mechanism for manually rotating the rotating shaft 121 may be used. The rotational resistance measurement device 124 comprises, for example, a torque meter for measuring the rotational torque of the rotating shaft 121. By electrically connecting the rotational resistance measurement device 124 to a personal computer, measurement data can be imported into the personal computer.

<Plastic flowability test device (3)>
As shown in Figures 5(a) and (b), a third embodiment of the plastic flowability test apparatus 130 is another example of a vane shear test apparatus. Figure 5(a) shows the side view of the third embodiment of the plastic flowability test apparatus 130, and Figure 5(b) shows the internal structure of the rotating barrel 131. This plastic flowability test apparatus 130 includes a rotating barrel 131 rotatably attached to the sample collection section 300, a plurality of vanes 132 axially extending from the inner surface of the rotating barrel 131 at equal intervals in the circumferential direction, a rotational drive device 133 that rotates the rotating barrel 131, and a rotational resistance measurement device 134 that measures the rotational resistance of the vanes 132.

In the third embodiment of the plastic flowability testing device 130, when the rotating barrel 131 filled with the sample is rotated by the rotary drive device 133, the shear resistance of the sample is applied to multiple vanes 132 installed inside the rotating barrel 131. The plastic flowability (shear resistance) of the sample can then be determined based on the rotational resistance value measured by the rotational resistance measuring device 134.

The rotational drive device 133 comprises, for example, an electric motor for rotating the rotating barrel 131 and an auxiliary device for transmitting the rotational force of the electric motor to the rotating barrel 131. Alternatively, a mechanism for manually rotating the rotating barrel 131 may be used. The rotational resistance measurement device 134 comprises, for example, a torque meter for measuring the rotational torque of the rotating barrel 131. By electrically connecting the rotational resistance measurement device 134 to a personal computer, measurement data can be imported into the personal computer.

<Plastic flowability test device (4)>
As shown in Figure 6, the plastic fluidity test apparatus 140 of the fourth embodiment is an embodiment of a shear test apparatus for determining the shear resistance of a sample by a penetration test. This plastic fluidity test apparatus 140 includes a penetration rod 141 that can penetrate into a sample recovery capsule 44 installed in the sample recovery section 300, a penetration device 142 that penetrates the penetration rod 141 into the sample recovery capsule 44, and a penetration resistance measuring device 143 that measures the penetration resistance value of the penetration rod 141. This plastic fluidity test apparatus 140 is configured to penetrate the penetration rod 141 into the sample recovery capsule 44, and the penetration device 142 and penetration resistance measuring device 143 are installed at the rear (tail side) of the sample recovery capsule 44.

In the fourth embodiment of the plastic flowability testing device 140, when the penetration rod 141 is inserted into the sample collection capsule 44 filled with the sample by the penetration device 142, a penetration resistance is applied to the penetration rod 141. The plastic flowability (shear resistance) of the sample can then be determined based on the penetration resistance value measured by the penetration resistance measuring device 143.

The penetration device 142 consists, for example, of a jack connected to the penetration rod 141. The penetration resistance measuring device 143 consists, for example, of a proving ring used in a cone penetrometer to measure the penetration resistance of the penetration rod 141. By electrically connecting the penetration resistance measuring device 143 to a personal computer, it is possible to import measurement data into the personal computer.

<Plastic flowability test device (5)>
7, the plastic fluidity test apparatus 150 of the fifth embodiment is a test apparatus in which the installation position of the penetrator 151 is different from that of the plastic fluidity test apparatus 140 of the fourth embodiment. In this plastic fluidity test apparatus 150, a penetrator 151 is used that penetrates the chamber partition (bulkhead) 20, so that the tip of the penetrator 151 protrudes into the chamber 10.

The other configurations are almost the same as those of the plastic fluidity test apparatus 140 of the fourth embodiment, and when the penetration rod 151 is penetrated into the chamber 10 filled with the sample via the sample recovery section 300 using the penetration device 152, a penetration resistance is applied to the penetration rod 151. Then, based on the penetration resistance value measured by the penetration resistance measuring device 153, the plastic fluidity (shear resistance) of the sample in the chamber 10 can be determined. Note that when conducting a plastic fluidity test on a sample, the penetration rod 151 is temporarily penetrated into the chamber 10, and the penetration rod 151 is not permanently installed in the chamber 10.

The penetration device 152 consists, for example, of a jack connected to the penetration rod 151. The penetration resistance measuring device 153 consists, for example, of a proving ring used in a cone penetrometer to measure the penetration resistance of the penetration rod 151. By electrically connecting the penetration resistance measuring device 153 to a personal computer, it is possible to import measurement data into the personal computer.

<Plastic flowability test device (6)>
8(a) and 8(b), the plastic fluidity test apparatus 160 of the sixth embodiment is an embodiment using a direct shear test apparatus. This plastic fluidity test apparatus 160 includes a shear box 161 in the sample collection section 300 that can move in a direction perpendicular to the sample intake direction, a moving device 162 that moves the shear box 161, a moving resistance measuring device 163 that measures the moving resistance of the shear box 161, and a moving displacement measuring device 164 that measures the moving displacement of the shear box 161. The plastic fluidity test apparatus 160 is a test apparatus conforming to the "Direct Shear Test of Soil" specified in the Geotechnical Society Standards: JGS 0560 and 0561.

In the sixth embodiment of the plastic flowability testing device 160, a shear box 161 is placed in the sample collection section 300 filled with sample, and the shear box 161 is moved by a moving device 162. The plastic flowability (shear resistance) of the sample can then be determined based on the measurements taken by the moving resistance measuring device 163 and the moving displacement measuring device 164.

Figure 8(a) shows the sixth embodiment of the plastic flowability testing device 160 as seen from the side, and Figure 8(b) shows the sixth embodiment of the plastic flowability testing device 160 as seen from the rear. The shear box 161 is supported by a frame 165 and can be moved up and down in Figure 8. In Figure 8(a), reference numeral 54 denotes a pressure gauge.

The moving device 162 may be, for example, a jack for moving the shear box 161 along the shear plane. The movement resistance measuring device 163 may be, for example, a load cell for measuring the shear resistance on the shear plane. The movement displacement measuring device 164 may be, for example, a dial gauge for measuring the amount of movement of the shear box 161. By electrically connecting the movement resistance measuring device 163 and the movement displacement measuring device 164 to a personal computer, measurement data can be imported into the personal computer.

<Plastic flowability test device (7)>
As shown in FIG. 9 , the plastic flowability test device 170 of the seventh embodiment is a device in which a measuring rod 173 having an accelerometer 171 and a strain gauge 172 attached to the tip thereof is extended into the chamber 10 via the sample recovery section 300, and a plastic flowability test of a sample in the chamber 10 is performed.

The seventh embodiment of the plastic flowability testing device 170 includes a measuring rod 173 that penetrates the chamber bulkhead 20 from within the sample collection section 300 and protrudes into the chamber 10, an insertion device 174 that inserts the measuring rod 173 into the chamber 10, and an accelerometer 171 and a strain gauge 172 attached to the tip of the measuring rod 173.

In the plastic flowability testing device 170 of the seventh embodiment, the strain characteristics (resistance and adhesive force) of the sample due to the insertion of the measuring rod 173 are determined based on the deformation rate based on the acceleration measured by the accelerometer 171 and the strain value measured by the strain gauge 172. The plastic flowability of the sample can then be determined based on the strain characteristics (resistance and adhesive force) of the sample. Note that when conducting a plastic flowability test of the sample, the measuring rod 173 is temporarily inserted into the chamber 10, and is not permanently placed in the chamber 10.

The insertion device 174 may consist, for example, of a jack connected to a measuring rod 173. The accelerometer 171 and strain gauge 172 are electrically connected to a personal computer so that measurement data can be imported into the computer.

<Plastic fluidity test device (8)>
As shown in Figure 10, the plastic flowability testing device 180 of the eighth embodiment is configured to attach a capsule 181 to a sample recovery section 300, measure the weight of the capsule 181 during the process of taking the sample into the capsule 181, and measure the time it takes for the capsule 181 to become filled with the sample, thereby determining the plastic flowability of the sample.

The eighth aspect of the plastic flowability testing device 180 includes a capsule 181 attached to the sample collection section 300, a capsule weight measuring device 182 that measures the weight of the capsule 181 during the process of incorporating the sample into the capsule 181, and a sample intake time measuring device 183 that measures the time it takes for the capsule 181 to become filled with sample.

In the eighth aspect of the plastic flowability testing device 180, the plastic flowability of the sample can be determined based on the weight of the capsule 181 measured by the capsule weight measuring device 182 and the sample uptake time measured by the sample uptake time measuring device 183.

The capsule weight measuring device 182 may be, for example, a weighing scale, and the sample intake time measuring device 183 may be, for example, a digital timer. To measure the sample intake time, for example, an earth pressure gauge may be attached to the tail end face of the capsule 181, and the time from when the sample begins to be taken into the capsule 181 until the earth pressure gauge detects the sample may be measured. Alternatively, the weight of the capsule 181 filled with sample may be calculated in advance each time from the volume of the capsule 181 and the specific gravity of the mud in the chamber 10, and the time from when the sample begins to be taken into the capsule 181 until the weight of the capsule 181 filled with sample may be measured. Furthermore, the electric ball valve 52 may be slightly opened, and the time from when the capsule 181 is filled with sample until the sample begins to leak out of the electric ball valve 52 may be measured. Furthermore, by electrically connecting the capsule weight measuring device 182 and the sample intake time measuring device 183 to a personal computer, measurement data can be imported into the personal computer.

<Plastic flowability test device (9)>
As shown in Figure 11, the plastic flowability testing device 190 of the ninth embodiment has a capsule 191 attached to a sample recovery section 300, a resistor 192 placed inside the capsule 191, and the plastic flowability of the sample is determined by measuring the movement resistance value generated when the resistor 192 placed inside the capsule 191 is moved while the capsule 191 is filled with the sample.

The ninth embodiment of the plastic flowability testing device 190 comprises a capsule 191 attached to the sample collection section 300, a resistor 192 installed within the capsule 191, an operating rod 193 that penetrates the rear end of the capsule 191 and connects to the resistor 192, a resistor moving device 194 that moves the resistor 192 within the capsule 191 via the operating rod 193, and a moving resistance measuring device 195 that measures the moving resistance of the resistor 192.

In the ninth aspect of the plastic flowability testing device 190, the resistor 192 placed in the capsule 191 filled with the sample is moved in the extraction direction (toward the tail) by the resistor moving device 194, and the movement resistance is measured by the movement resistance measuring device 195, thereby determining the plastic flowability of the sample. The extracted resistor 192 may also be moved again in the pushing direction (toward the cutter head) and the movement resistance measured by the movement resistance measuring device 195, thereby determining the plastic flowability of the sample. Furthermore, the resistor 192 may be repeatedly pulled out and pushed in, and the movement resistance of the resistor 192 may be measured.

The resistor 192 is, for example, a plate-shaped, spherical, or plate-shaped member with holes. The resistor movement device 194 is, for example, a jack connected to the operating lever 193. The movement resistance measurement device 195 is, for example, a proving ring used in a cone penetrometer to measure the movement resistance of the resistor 192. By electrically connecting the movement resistance measurement device 195 to a personal computer, measurement data can be imported into the personal computer.

<Plastic flowability test device (10)>
12, the plastic flowability testing device 200 of the tenth aspect has a capsule 201 attached to a sample recovery unit 300, a vibrating body 202 and an accelerometer 203 installed inside the capsule 201, and vibrates the vibrating body 202 installed inside the capsule 201 while the capsule 201 is filled with a sample.The plastic flowability of the sample is then determined based on changes in amplitude and frequency that occur when the vibrating body 202 is vibrated.

The plastic flowability testing device 200 of the tenth aspect comprises a capsule 201 attached to the sample collection unit 300, a vibrating body 202 and an accelerometer 203 provided within the capsule 201, and a power supply 205 connected to the vibrating body 202 via a power cable 204. In this embodiment, a signal line is installed together with the power cable 204.

In the tenth aspect of the plastic flowability testing device 200, power is supplied from a power source 205 to a vibrating body 202 placed inside a capsule 201 filled with a sample, causing the vibrating body 202 to vibrate, and the acceleration of the vibrating body 202 is measured by an accelerometer 203, and the plastic flowability of the sample can be determined by measuring changes in amplitude and frequency.

The power source 205 may be, for example, a battery. Furthermore, by electrically connecting the accelerometer 203 to a personal computer, measurement data can be imported into the personal computer.

<Plastic flowability test device (11)>
The plastic flowability test apparatus 210 of the eleventh aspect is an embodiment using a vibration viscometer, as shown in Fig. 13. In this plastic flowability test apparatus 210, a capsule 211 is attached to the sample recovery unit 300, an oscillator 212 is housed in the capsule 211, and the oscillator 212 installed in the capsule 211 is vibrated while the capsule 211 is filled with a sample. The plastic flowability of the sample is determined based on the vibration amplitude generated when the oscillator 212 is vibrated, or the drive power value when the oscillator 212 is vibrated at a predetermined vibration amplitude.

The principle of determining the plastic fluidity of a sample using a vibration viscometer is explained below. When the oscillator 212 is vibrated at a constant frequency, a frictional force due to viscosity is generated between the oscillator 212 and the sample, and the amplitude of the oscillation of the oscillator 212 changes depending on the magnitude of this frictional force. Because there is a correlation between the oscillation amplitude of the oscillator 212 and the viscosity (plastic fluidity) of the sample, the plastic fluidity of the sample can be determined based on the oscillation amplitude of the oscillator 212.

In addition, the driving power for vibrating the vibrator 212 is proportional to the product of the viscosity and density of the sample. Therefore, the driving power for vibrating the vibrator 212 can be changed so that the vibration amplitude of the vibrator 212 reaches a predetermined value, and the plastic flow properties of the sample can be determined based on the driving power value at this time.

The plastic flowability testing device 210 of the eleventh aspect comprises a capsule 211 attached to the sample collection unit 300, a vibrator 212 housed within the capsule 211, a drive power supply control unit 213 for controlling the supply of drive power that electromagnetically vibrates the vibrator 212, and a vibration amplitude measurement unit 214 for measuring the vibration amplitude value of the vibrator 212.

The drive power supply control unit 213 is a device that supplies drive power to electromagnetically vibrate the vibrator 212 and controls the drive power value. Although not shown, it consists of a drive power supply unit for supplying drive power and a drive power control unit for controlling the drive power value. Therefore, if the drive power supplied to the vibrator 212 is always constant, only the drive power supply unit needs to function. Furthermore, if the vibration amplitude of the vibrator 212 is to be controlled to a predetermined value, the drive power value is controlled by the drive power control unit based on the vibration amplitude value measured by the vibration amplitude measurement unit 214, and drive power is supplied to the vibrator 212.

In the plastic flowability testing device 210 of the eleventh aspect, the drive power supply control unit 213 controls the supply of drive power to the oscillator 212 installed in the capsule 211 filled with the sample, causing the oscillator 212 to vibrate electromagnetically, and the vibration amplitude measurement unit 214 measures the vibration amplitude value of the oscillator 212, thereby determining the plastic flowability of the sample. Furthermore, the drive power supplied to the oscillator 212 by the drive power supply control unit 213 is controlled so that the vibration amplitude value measured by the vibration amplitude measurement unit 214 becomes a predetermined value, and the plastic flowability of the sample can be determined based on the drive power value at this time.

The drive power supply control unit 213 consists of, for example, a battery and a control device that controls the supplied power. The vibration amplitude measurement unit 214 consists of, for example, a displacement sensor and an accelerometer. By electrically connecting the drive power supply control unit 213 and the vibration amplitude measurement unit 214 to a personal computer, measurement data can be imported into the personal computer.

<Plastic fluidity test method>
The method for testing the plastic fluidity of a sample under chamber pressure in a shield machine according to the present invention is a testing method for determining the plastic fluidity of a sample using the fluidity test devices described above. Specifically, as shown in Figure 14, the method includes a step (S1) of installing a sample recovery unit 300 connected to the chamber 10 of the shield machine or a test portion of the plastic fluidity test device in the chamber 10 via the sample recovery unit 300, and a step (S2) of using the plastic fluidity test device to perform a plastic fluidity test on the recovered sample under a pressure equivalent to that in the chamber 10. When performing a plastic fluidity test on a sample in the chamber 10, the test portion of the plastic fluidity test device is temporarily installed in the chamber 10.

The plastic flowability test apparatus used in the plastic flowability test method is an apparatus for measuring the plastic flowability of a sample in the sample recovery section 300 or in the chamber 10 via the sample recovery section 300, and any of the above-mentioned embodiments can be used. Furthermore, the plastic flowability test apparatus used in the plastic flowability test method of the present invention is not limited to the above-mentioned embodiments, and any apparatus can be used as long as it is capable of measuring the plastic flowability of a sample and can be installed in the sample recovery section 300 or can be temporarily installed in the chamber 10 via the sample recovery section 300.

10 Chamber 20 Chamber bulkhead
30 Opening 31 Mounting opening 32 Closure plate 33 Recovery pipe support member 40 Sample recovery means 41 Recovery pipe 42 First ball valve 43 Emergency ball valve 43a Opening/closing handle 44 Sample recovery capsule 45 Pipe joint 46 Tightening bolt 50 Air vent means 51 Air vent pipe 52 Electric ball valve 53 Silencer 54 Pressure gauge 60 Second ball valve 70 In-chamber sample recovery device 110 Plastic flowability test device (1)
111 Rotating shaft 112 Vane 113 Rotation drive device 114 Rotation resistance measuring device 120 Plastic flowability test device (2)
121 Rotating shaft 122 Vane 123 Rotation drive device 124 Rotation resistance measuring device 130 Plastic flowability test device (3)
131 Rotating body 132 Vane 133 Rotation drive device 134 Rotation resistance measuring device 140 Plastic flowability test device (4)
141 Penetration rod 142 Penetration device 143 Penetration resistance measuring device 150 Plastic fluidity test device (5)
151 Penetration rod 152 Penetration device 153 Penetration resistance measuring device 160 Plastic fluidity test device (6)
161 Shear box 162 Moving device 163 Moving resistance measuring device 164 Moving displacement measuring device 165 Frame 170 Plastic flowability test device (7)
171 Accelerometer 172 Strain gauge 173 Measuring rod 174 Insertion device 180 Plastic flow test device (8)
181 Capsule 182 Capsule weight measuring device 183 Sample intake time measuring device 190 Plastic flowability test device (9)
191 Capsule 192 Resistor 193 Operating knob 194 Resistor moving device 195 Moving resistance measuring device 200 Plastic flowability test device (10)
201 Capsule 202 Vibrator 203 Accelerometer 204 Power cable (signal line)
205 Power supply 210 Plastic flowability test device (11)
211 Capsule 212 Oscillator 213 Drive power supply control unit 214 Vibration amplitude measurement unit 300 Sample recovery unit

Claims (10)

In a shield machine having a sample collection section provided so as to be in communication with a chamber of the shield machine,
a plastic fluidity testing device for performing a plastic fluidity test on the excavated soil and sand taken into the chamber under pressure within the chamber by installing a test site in a sample collection section that is in communication with the chamber ;
the plastic flowability test device is a device for performing a plastic flowability test on the sample recovered in the sample recovery section while maintaining a pressure state equivalent to the pressure inside the chamber ,
the sample collection unit is not provided inside the chamber, and collects excavated soil and sand from an opening provided in the chamber partition wall;
1. A device for testing the plastic flow properties of a sample under pressure in a chamber of a shield machine. a first ball valve is provided to function as an opening opening/closing means;
2. An apparatus for testing plastic flow properties of a specimen under pressure in a chamber of a shield machine according to claim 1. a first ball valve functioning as the opening opening/closing means is provided between the opening and the sample recovery unit;
3. An apparatus for testing plastic flow properties of a specimen under pressure in a chamber of a shield machine according to claim 2. The plastic flowability test device is
a rotating body rotatably attached to the sample collection unit;
a plurality of vanes provided in the axial direction so as to protrude at equal intervals in the circumferential direction from the inner peripheral surface of the rotating barrel;
a rotation drive device that drives the rotating body to rotate;
a rotational resistance measuring device for measuring the rotational resistance of the vane;
Equipped with
The plastic flowability of the sample is determined based on the rotational resistance value measured by the rotational resistance measuring device.
2. An apparatus for testing plastic flow properties of a specimen under pressure in a chamber of a shield machine according to claim 1. The plastic flowability test device is
a penetration rod that can penetrate into the sample recovery section;
a penetration device that penetrates the penetration rod into the sample collection section;
A penetration resistance measuring device for measuring the penetration resistance value of the penetration rod;
Equipped with
The plastic flowability of the sample is determined based on the penetration resistance value measured by the penetration resistance measuring device.
2. An apparatus for testing plastic flow properties of a specimen under pressure in a chamber of a shield machine according to claim 1. The plastic flowability test device is
a shear box in the sample recovery section that is movable in a direction perpendicular to the sample intake direction;
a moving device for moving the shear box;
a movement resistance measuring device for measuring the movement resistance of the shear box;
a displacement measuring device for measuring the displacement of the shear box;
Equipped with
determining the plastic flowability of the sample based on the measured values of the movement resistance measuring device and the movement displacement measuring device;
2. An apparatus for testing plastic flow properties of a specimen under pressure in a chamber of a shield machine according to claim 1. The plastic flowability test device is
a capsule attached to the sample collection unit;
a capsule weight measuring device that measures the weight of the capsule during the process of introducing the sample into the capsule;
a sample intake time measurement device that measures the time it takes for the capsule to be filled with the sample;
Equipped with
The plastic flowability of the sample is determined based on the weight of the capsule measured by the capsule weight measuring device and the sample uptake time measured by the sample uptake time measuring device.
2. An apparatus for testing plastic flow properties of a specimen under pressure in a chamber of a shield machine according to claim 1. The plastic flowability test device is
a capsule attached to the sample collection unit;
a resistor disposed within the capsule;
a resistor moving device that moves the resistor within the capsule;
a movement resistance measuring device for measuring the movement resistance of the resistor;
Equipped with
The plastic flowability of the sample is determined based on the movement resistance value measured by the movement resistance measuring device.
2. An apparatus for testing plastic flow properties of a specimen under pressure in a chamber of a shield machine according to claim 1. The plastic flowability test device is
a capsule attached to the sample collection unit;
a vibrator housed in the capsule;
a vibration device that vibrates the vibrating body;
an accelerometer for measuring acceleration when the vibrating body is vibrated;
Equipped with
The plastic flow property of the sample is determined based on the changes in the amplitude and frequency of the vibrating body measured by the accelerometer.
2. An apparatus for testing plastic flow properties of a specimen under pressure in a chamber of a shield machine according to claim 1. The plastic flowability test device is
a capsule attached to the sample collection unit;
a vibrator housed in the capsule;
a drive power supply control unit for controlling the supply of drive power that electromagnetically vibrates the vibrator;
a vibration amplitude measuring unit for measuring a vibration amplitude value of the vibrator;
Equipped with
determining the plastic flow property of the sample based on the vibration amplitude value measured by the vibration amplitude measurement unit or the driving power value in the driving power supply control unit when the vibrator is vibrated at a predetermined vibration amplitude;
2. An apparatus for testing plastic flow properties of a specimen under pressure in a chamber of a shield machine according to claim 1.