A visual acoustic emission ring shear instrument

Abstract

The invention provides a visual acoustic emission ring shear instrument. The instrument comprises a main structure, a power unit, a data acquisition device, and an integral base. The main structure's power unit drives the rotation of a lower moving disk, which in turn drives the rotation of a sample held in a central fixed cylinder. The sample's movement transmits force to an upper follower disk, where it is measured by a force sensor and collected and transmitted by a data acquisition box. The acoustic emission signal is measured by an acoustic emission probe placed in a small hole in the upper follower disk and collected and stored by an external acoustic emission instrument. The instrument can measure frictional dislocation in granular materials of varying particle sizes and features convenient installation, sample loading, and sampling, preventing sample extrusion. Furthermore, the acoustic emission probe is easily positioned.

Description

Technical Field

[0001] The present invention relates to the technical field of material detection, in particular to a visual acoustic emission ring shear instrument. Background Art

[0002] Active earthquake fault zones, complex geological environments, and a large proportion of mountainous terrain frequently lead to natural disasters such as strong earthquakes, collapses, landslides, and debris flows, which directly or indirectly cause casualties, property losses, and damage to resources and the environment. These disasters involve rock and soil masses, including boulders, gravel, silt, and clay minerals. These disasters occur due to instability caused by fracture and friction in these rock and soil masses, necessitating the study of frictional instability in granular bodies, which are mixtures of mesoscopic particles.

[0003] The traditional ring shear apparatus consists of a shear box composed of a pair of metal rings. The specimen is placed inside the ring-shaped shear box. Normal stress is applied to the fixed upper portion of the specimen, while the lower shear box applies torque to the specimen by rotating. This type of ring shear apparatus has the advantage of allowing precise adjustment of specimen parameters, applied normal stress, and rotation speed, either manually or by computer, making it suitable for high-precision testing. However, it has some drawbacks for studying friction in granular materials:

[0004] 1) Only a specific shear surface can be measured, and the specimen size cannot be changed. For shearing of granular materials, it is necessary to understand not only the shear behavior of the external surface but also the internal friction of the granular material. Furthermore, the shear box of the ring shear apparatus is a finished product, so the specimen size is fixed and cannot be changed at will.

[0005] 2) The specimen is easily squeezed out of the shear box during the test. Granular materials contain many particles with large gaps between them. Rotating the shear box may cause the particles to rearrange and easily squeeze out the edge particles.

[0006] 3) Changes in the specimen during the test, such as the formation of microcracks, deformation, and damage of the specimen, cannot be observed.

[0007] Therefore, it is necessary to develop a visualization instrument suitable for studying granular shear to address the above shortcomings. Summary of the Invention

[0008] The purpose of the present invention is to provide a visual acoustic emission ring shear instrument to solve the problems existing in the prior art.

[0009] The technical solution adopted to achieve the purpose of the present invention is as follows: a visual acoustic emission ring shear instrument, including a main structure and a data acquisition device.

[0010] The main structure includes a lower moving plate, a middle fixed cylinder, an upper following plate and a middle fixed column.

[0011] The lower moving plate comprises a support plate I, several columns, a rotating cylinder, and gear I. Support plate I rests on the upper surface of the columns. Its surface features coaxially arranged holes and annular mounting grooves. The upper end of the rotating cylinder extends through the hole, while the outer ring of its lower end is fitted with gear I. Gear I is connected to a chain.

[0012] The central fixed cylinder includes an outer cylinder, an inner cylinder, an inner fixed disk, a rotatable ring at the lower end, and a non-rotatable ring at the upper end. The outer cylinder and inner cylinder are made of transparent material. The lower end of the outer cylinder is embedded in an annular embedding groove. The inner cylinder is arranged in the inner cavity of the outer cylinder. The outer cylinder and inner cylinder are coaxially arranged. The inner fixed disk is arranged in a hole. The inner cylinder rests on and is fixed to the inner fixed disk. The outer cylinder and inner cylinder enclose a cylindrical annular storage space. The non-rotatable ring at the upper end and the rotatable ring at the lower end are respectively arranged at the upper and lower ends of the cylindrical annular storage space. The lower surface of the rotatable ring at the lower end is connected to the upper surface of the rotating cylinder. The upper surface of the rotatable ring at the lower end is provided with serrations. The lower surface of the non-rotatable ring at the upper end is provided with serrations. The outer cylinder, inner cylinder, rotatable ring at the lower end, and non-rotatable ring at the upper end together enclose a sample chamber.

[0013] The upper follower disc cover is positioned above the central fixed cylinder. The upper follower disc comprises a disc and a raised barrel. The disc is fixed to the upper surface of the upper non-rotatable ring. The disc seals the upper opening of the inner cylinder. The sidewall of the disc is provided with a plurality of grooves. An acoustic emission probe is disposed in each groove. The lower end of the acoustic emission probe abuts against the upper surface of the upper non-rotatable ring. The raised barrel is a cylindrical structure with an open lower end and a closed upper end. The raised barrel is disposed on the upper surface of the disc. The lower opening of the raised barrel is sealed by the disc. A reserved opening is provided on the sidewall of the raised barrel. A raised block is disposed on the sidewall of the raised barrel next to the reserved opening.

[0014] The column body of the middle fixed column sequentially passes through the inner cavity of the rotating cylinder, the inner fixed disk, the inner cavity of the inner cylinder and the disk, and then extends into the inner cavity of the raised barrel. The inner fixed disk is fixedly connected to the side wall of the middle fixed column.

[0015] The data acquisition device includes a force sensor and a data acquisition box. The handle of the force sensor is removably fixed to the shaft of the central fixed column after passing through a reserved opening. The main body of the force sensor extends to the side of the raised block. The force sensor is connected to the data acquisition box.

[0016] During operation, the sample chamber is filled with a rock and soil sample. The serrations of the upper, non-rotatable ring and the lower, rotatable ring engage the rock and soil sample. The chain drives the rotating cylinder, which in turn drives the rock and soil sample, transmitting torsional force to the upper follower plate. The force sensor contacts the raised block, measures the torsional force, and transmits it to the data acquisition box.

[0017] Furthermore, the device includes a power unit. The power unit includes a distribution box, a motor, gear II, and a chain. The motor is connected to the distribution box. The output end of the motor is provided with gear II. Gear II is connected to the chain. The distribution box changes the speed of the motor by changing the power it provides.

[0018] Furthermore, the invention also comprises a base, the lower surface of which is provided with a rubber sheet.

[0019] Furthermore, the lower movable plate further comprises a support plate II. The plurality of upright posts are sandwiched between the support plate I and the support plate II.

[0020] Furthermore, the outer cylinder and the inner cylinder are both made of transparent acrylic material.

[0021] Furthermore, the disc is provided with a pressing sheet which is fixed to the upper surface of the disc by bolts.

[0022] The technical effect of the present invention is unquestionable: it can measure the friction and dislocation of granular bodies with different particle sizes, has the characteristics of convenient installation and sampling, the sample will not be squeezed out, and it is easy to place the acoustic emission probe. The whole composed of the lower support disc and the column and the middle column jointly support and fix the main body, ensuring that the upper and middle structures are firm and the installation and positioning are accurate. The outer cylinder is embedded for easy sampling. The transparent acrylic inner and outer cylinders are used to facilitate the observation of changes such as movement and damage of the sample during the experiment. The use of a serrated ring is conducive to engaging with the sample and transmitting torsional force. The use of an upper ring that can only move vertically ensures that only torsional force can be transmitted and is easy to disassemble. A small hole and a preset pressure plate are reserved for the acoustic emission probe to reach the upper surface of the non-rotating ring to ensure signal reception. The use of a base with different heights ensures that the chain is transmitted horizontally to reduce resistance. A rubber sheet is placed under the base to reduce vibration and noise. The force sensor with a spiral handle is easy to adjust and disassemble. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the overall structure of the visual acoustic emission ring shear instrument;

[0024] Figure 2 Schematic diagram of the lower moving disk;

[0025] Figure 3 This is a schematic diagram of the main structure;

[0026] Figure 4Schematic diagram of the power unit.

[0027] In the figure: base 1, power device 2, distribution box 201, motor 202, gear II 203, chain 204, data acquisition device 3, force sensor 301, data acquisition box 302, lower moving disk 5, support plate I 501, hole 5011, annular embedding groove 5012, support plate II 502, column 503, rotating cylinder 504, gear I 505, middle fixed cylinder 6, outer cylinder 601, inner cylinder 602, inner fixed disk 603, lower end rotatable ring 604, upper end non-rotatable ring 605, upper follow-up disk 7, disk 701, groove 7011, pressing piece 7012, raised barrel 702, reserved opening 7021, raised block 7022, middle fixed column 8. DETAILED DESCRIPTION

[0028] The present invention will be further described below with reference to the following examples, but it should not be understood that the scope of the present invention is limited to the following examples. Without departing from the above technical ideas of the present invention, various substitutions and modifications can be made according to common technical knowledge and customary means in the art, and all should be included in the scope of protection of the present invention. Example 1

[0029] See also Figure 1 This embodiment provides a visual acoustic emission ring shear instrument, including a main structure, a base 1, a power device 2 and a data acquisition device 3.

[0030] See also Figure 3 The main structure includes a lower moving plate 5, a middle fixed cylinder 6, an upper follower plate 7 and a middle fixed column 8.

[0031] See also Figure 2 The lower moving plate 5 includes a support plate I 501, a support plate II 502, a column 503, a rotating cylinder 504 and a gear I 505. The support plate I 501 is placed on the upper surface of the column 503. The column 503 is sandwiched between the support plate I 501 and the support plate II 502.

[0032] The support plate I 501 has a coaxial hole 5011 and an annular fixing groove 5012 . The upper end of the rotating cylinder 504 extends out of the hole 5011 , and the outer ring of the lower end is provided with a gear I 505 . The gear I 505 is connected to the chain 204 .

[0033] The central fixed cylinder 6 comprises an outer cylinder 601, an inner cylinder 602, an inner fixed disk 603, a lower rotatable ring 604, and an upper non-rotatable ring 605. Both the outer cylinder 601 and the inner cylinder 602 are made of transparent acrylic. The lower end of the outer cylinder 601 is embedded in the annular embedding groove 5012. The inner cylinder 602 is disposed within the inner cavity of the outer cylinder 601. The outer cylinder 601 and inner cylinder 602 are coaxially arranged. The inner fixed disk 603 is disposed in the hole 5011. The inner cylinder 602 rests on and is fixed to the inner fixed disk 603. The outer cylinder 601 and inner cylinder 602 enclose a cylindrical housing. The upper non-rotatable ring 605 and the lower rotatable ring 604 are disposed at the upper and lower ends of the cylindrical housing, respectively. The lower surface of the lower rotatable ring 604 is connected to the upper surface of the rotating cylinder 504. The upper surface of the lower rotatable ring 604 is provided with serrations. The lower surface of the upper non-rotatable ring 605 is provided with serrations. The outer cylinder 601, the inner cylinder 602, the lower rotatable ring 604 and the upper non-rotatable ring 605 together enclose a sample chamber.

[0034] The upper follower disc 7 is positioned above the middle fixed cylinder 6. The upper follower disc 7 includes a disc 701 and a raised barrel 702. The disc 701 is fixed to the upper surface of the upper non-rotatable ring 605. The disc 701 blocks the upper opening of the inner cylinder 602. Four grooves 7011 are provided on the sidewall of the disc 701. The four grooves 7011 are arranged in a circular pattern. Adjacent grooves 7011 are spaced 90 degrees apart. Acoustic emission probes are positioned in the grooves 7011. The lower end of the acoustic emission probe is pressed against the upper surface of the upper non-rotatable ring 605. A pressure plate 7012 is provided next to each groove 7011. The pressure plate 7012 is bolted to the upper surface of the disc 701. The pressure plates 7012 enable the acoustic emission probe to capture wave signals with sufficient sensitivity, receiving signals with minimal attenuation.

[0035] The raised barrel 702 is a cylindrical structure with an open lower end and a closed upper end. The raised barrel 702 is disposed on the upper surface of the disc 701. The lower open end of the raised barrel 702 is blocked by the disc 701. A reserved opening 7021 is provided on the sidewall of the raised barrel 702. A raised block 7022 is provided on the sidewall of the raised barrel 702, adjacent to the reserved opening 7021.

[0036] The shaft of the intermediate fixed column 8 sequentially passes through the inner cavity of the rotating cylinder 504, the internal fixed disk 603, the inner cavity of the inner cylinder 602, and the disk 701, before extending into the inner cavity of the raised barrel 702. The intermediate fixed column 8 extends through the upper, middle, and lower portions of the main structure, providing support and fixation. The internal fixed disk 603 is fixedly connected to the sidewall of the intermediate fixed column 8.

[0037] The data acquisition device 3 includes a force sensor 301 and a data acquisition box 302. The handle of the force sensor 301 passes through a reserved opening 7021 and can be removably mounted on the shaft of the intermediate fixed column 8. The main body of the force sensor 301 extends to the side of the raised block 7022. The force sensor 301 is connected to the data acquisition box 302.

[0038] During operation, the sample chamber is filled with a rock sample. The serrations of the upper non-rotatable ring 605 and the lower rotatable ring 604 engage the rock sample, ensuring that the sample does not slip during shearing. The chain 204 rotates the rotating cylinder 504, which in turn rotates the rock sample, transmitting torsional force to the upper follower plate 7. The force sensor 301 contacts the raised block 7022, measuring the torsional force and transmitting it to the data acquisition box 302.

[0039] The power unit 2 includes a distribution box 201, a motor 202, a gear II 203, and a chain 204. The motor 202 is connected to the distribution box 201. The output end of the motor 202 is provided with a gear II 203. The gear II 203 is connected to the chain 204. The distribution box 201 changes the speed of the motor 202 by changing the power it provides.

[0040] The base 1 comprises a main structural base and a motor lift base. The motor lift base maintains a substantially horizontal transmission of the chain 204, which reduces resistance. A rubber sheet is provided on the lower surface of the base 1 to reduce vibration and noise during operation of the motor 202.

[0041] This embodiment provides a visual experimental instrument for monitoring acoustic emission signals and shear behavior. Acoustic emission technology is a non-destructive testing technology. Friction in rock and soil will release energy, and this energy will propagate in the form of elastic waves. This form of signal is called an acoustic emission signal. Compared with direct shear tests, uniaxial shear tests, etc., ring shear tests can study the shear resistance of materials under large deformations. During this process, a large number of acoustic emission signals can be collected, which is convenient for post-processing analysis and summarizing the laws. By collecting acoustic emission signals and performing some post-processing analysis, the laws of internal dislocation and particle friction movement of rock and soil can be obtained, thereby deepening the understanding of the disaster mechanism. Example 2

[0042] This embodiment provides a basic visual acoustic emission ring shear instrument, including a main structure and a data acquisition device 3.

[0043] The main structure includes a lower moving plate 5 , a middle fixed cylinder 6 , an upper follower plate 7 and a middle fixed column 8 .

[0044] The lower moving plate 5 comprises a support plate I 501, a column 503, a rotating cylinder 504, and a gear I 505. The support plate I 501 rests on the upper surface of the column 503. The surface of the support plate I 501 has a coaxial hole 5011 and an annular retaining groove 5012. The upper end of the rotating cylinder 504 extends out of the hole 5011, and the outer ring of the lower end is fitted with a gear I 505. The gear I 505 is connected to the chain 204.

[0045] The central fixed cylinder 6 comprises an outer cylinder 601, an inner cylinder 602, an inner fixed disk 603, a lower rotatable ring 604, and an upper non-rotatable ring 605. The outer cylinder 601 and inner cylinder 602 are made of transparent material. The lower end of the outer cylinder 601 is embedded in the annular embedding groove 5012. The inner cylinder 602 is disposed within the inner cavity of the outer cylinder 601. The outer cylinder 601 and inner cylinder 602 are coaxially arranged. The inner fixed disk 603 is disposed in the hole 5011. The inner cylinder 602 rests on and is fixed to the inner fixed disk 603. The outer cylinder 601 and inner cylinder 602 enclose a cylindrical housing. The upper non-rotatable ring 605 and the lower rotatable ring 604 are disposed at the upper and lower ends of the cylindrical housing, respectively. The lower surface of the lower rotatable ring 604 is connected to the upper surface of the rotating cylinder 504. The upper surface of the lower rotatable ring 604 is provided with serrations. The lower surface of the upper non-rotatable ring 605 is provided with serrations. The outer cylinder 601, the inner cylinder 602, the lower rotatable ring 604 and the upper non-rotatable ring 605 together enclose a sample chamber.

[0046] The upper follower disc 7 is positioned above the middle fixed cylinder 6. The upper follower disc 7 comprises a disc 701 and a raised barrel 702. The disc 701 is fixed to the upper surface of the upper non-rotatable ring 605. The disc 701 blocks the upper open end of the inner cylinder 602. The sidewall of the disc 701 is provided with multiple grooves 7011. Acoustic emission probes are positioned within the grooves 7011. The lower end of the acoustic emission probe abuts against the upper surface of the upper non-rotatable ring 605. The raised barrel 702 is a cylindrical structure with an open lower end and a closed upper end. The raised barrel 702 is positioned on the upper surface of the disc 701. The lower open end of the raised barrel 702 is blocked by the disc 701. A reserved opening 7021 is provided on the sidewall of the raised barrel 702. A protruding block 7022 is provided on the side wall of the protruding barrel 702 beside the reserved opening 7021 .

[0047] The shaft of the intermediate fixed column 8 passes through the inner cavity of the rotating cylinder 504, the inner fixed disk 603, the inner cavity of the inner cylinder 602 and the disk 701 in sequence, and then extends into the inner cavity of the raised cylinder 702. The inner fixed disk 603 is fixedly connected to the side wall of the intermediate fixed column 8.

[0048] The data acquisition device 3 includes a force sensor 301 and a data acquisition box 302. The handle of the force sensor 301 passes through a reserved opening 7021 and can be removably mounted on the shaft of the intermediate fixed column 8. The main body of the force sensor 301 extends to the side of the raised block 7022. The force sensor 301 is connected to the data acquisition box 302.

[0049] During operation, the sample chamber is filled with a rock sample. The serrations of the upper non-rotatable ring 605 and the lower rotatable ring 604 engage the rock sample, ensuring that the sample does not slip during shearing. The chain 204 rotates the rotating cylinder 504, which in turn rotates the rock sample, transmitting torsional force to the upper follower plate 7. The force sensor 301 contacts the raised block 7022, measuring the torsional force and transmitting it to the data acquisition box 302. Example 3

[0050] This embodiment has the same primary structure as that of Embodiment 2, but further includes a power unit 2. The power unit 2 comprises a distribution box 201, a motor 202, a gear II 203, and a chain 204. The motor 202 is connected to the distribution box 201. The output end of the motor 202 is provided with a gear II 203. The gear II 203 is connected to the chain 204. The distribution box 201 changes the speed of the motor 202 by varying the power supplied. Example 4

[0051] The main structure of this embodiment is the same as that of embodiment 2, wherein the embodiment further comprises a base 1. A rubber sheet is provided on the lower surface of the base 1. Example 5

[0052] The main structure of this embodiment is the same as that of embodiment 2, wherein the lower movable plate 5 further includes a support plate II 502. The upright column 503 is sandwiched between the support plate I 501 and the support plate II 502. Example 6

[0053] The main structure of this embodiment is the same as that of embodiment 2, wherein the outer cylinder 601 and the inner cylinder 602 are both made of transparent acrylic material. Example 7

[0054] The main structure of this embodiment is the same as that of embodiment 2, wherein the disc 701 further has a pressing piece 7012. The pressing piece 7012 is fixed to the upper surface of the disc 701 by bolts.

Claims

1. A visual acoustic emission ring shear instrument, characterized by: It includes a main structure and a data acquisition device (3); The main structure comprises a lower movable plate (5), a middle fixed cylinder (6), an upper follower plate (7) and a middle fixed column (8); The lower movable plate (5) includes a support plate I (501), a plurality of columns (503), a rotating cylinder (504) and a gear I (505); the support plate I (501) is placed on the upper surface of the column (503); the support plate I (501) has a coaxially arranged hole (5011) and an annular embedded groove (5012) on its plate surface; the upper end of the rotating cylinder (504) extends out of the hole (5011), and the outer ring of the lower end is provided with a gear I (505); the gear I (505) is connected to the chain (204); The middle fixed cylinder (6) comprises an outer cylinder (601), an inner cylinder (602), an inner fixed disk (603), a rotatable ring at the lower end (604) and a non-rotatable ring at the upper end (605); the outer cylinder (601) and the inner cylinder (602) are made of transparent material; the lower end of the outer cylinder (601) is embedded in the annular embedding groove (5012); the inner cylinder (602) is arranged in the inner cavity of the outer cylinder (601); the outer cylinder (601) and the inner cylinder (602) are coaxially arranged; the inner fixed disk (603) is arranged in the hole (5011); the inner cylinder (602) is placed and fixed on the inner fixed disk (6012). 3) on; the outer cylinder (601) and the inner cylinder (602) enclose a circular cylindrical accommodating space; the upper non-rotatable circular ring (605) and the lower rotatable circular ring (604) are respectively arranged at the upper and lower ends of the circular cylindrical accommodating space; the lower surface of the lower rotatable circular ring (604) is connected to the upper surface of the rotating cylinder (504); the upper surface of the lower rotatable circular ring (604) is provided with serrations; the lower surface of the upper non-rotatable circular ring (605) is provided with serrations; the outer cylinder (601), the inner cylinder (602), the lower rotatable circular ring (604) and the upper non-rotatable circular ring (605) enclose a sample cavity; The upper follower disc (7) is covered on the upper part of the middle fixed cylinder (6); the upper follower disc (7) includes a disc (701) and a raised barrel (702); the disc (701) is fixed on the upper surface of the upper non-rotatable ring (605); the disc (701) blocks the upper end opening of the inner cylinder (602); a plurality of grooves (7011) are provided on the side wall of the disc (701); an acoustic emission probe is arranged in the groove (7011); the lower end of the acoustic emission probe is tightly against the inner cylinder (602); On the upper surface of the non-rotatable ring (605) at the upper end; the raised barrel (702) is a barrel structure with an open lower end and a closed upper end; the raised barrel (702) is arranged on the upper surface of the disc (701); the lower open end of the raised barrel (702) is blocked by the disc (701); a reserved opening (7021) is provided on the side wall of the raised barrel (702); a raised block (7022) is provided on the side wall of the raised barrel (702) next to the reserved opening (7021); The body of the intermediate fixed column (8) sequentially passes through the inner cavity of the rotating cylinder (504), the inner fixed disk (603), the inner cavity of the inner cylinder (602), and the disk (701), and then extends into the inner cavity of the raised barrel (702); the inner fixed disk (603) is fixedly connected to the side wall of the intermediate fixed column (8); The data acquisition device (3) comprises a force sensor (301) and a data acquisition box (302); the handle of the force sensor (301) is detachably mounted on the column body of the middle fixed column (8) after passing through the reserved opening (7021); the body of the force sensor (301) extends to the side of the protruding block (7022); the force sensor (301) is connected to the data acquisition box (302); During operation, a rock and soil sample is filled in the sample cavity; the saw teeth of the upper non-rotatable ring (605) and the lower rotatable ring (604) are embedded in the rock and soil sample; the chain (204) drives the rotating cylinder (504) to rotate, and the lower rotatable ring (604) drives the rock and soil sample to rotate, transmitting the torsional force to the upper follower plate (7); the force sensor (301) contacts the protruding block (7022) to measure the torsional force, and transmits it to the data acquisition box (302).

2. A visual acoustic emission ring shear instrument according to claim 1, characterized in that: The invention also includes a power device (2); the power device (2) includes a distribution box (201), a motor (202), a gear II (203) and a chain (204); the motor (202) is connected to the distribution box (201); the output end of the motor (202) is provided with a gear II (203); the gear II (203) is connected to the chain (204); the distribution box (201) changes the speed of the motor (202) by changing the power provided.

3. A visual acoustic emission ring shear instrument according to claim 1, characterized in that: It also includes a base (1); the lower surface of the base (1) is provided with a rubber sheet.

4. A visual acoustic emission ring shear instrument according to claim 1, characterized in that: The lower movable plate (5) further includes a support plate II (502); the plurality of upright columns (503) are sandwiched between the support plate I (501) and the support plate II (502).

5. A visual acoustic emission ring shear instrument according to claim 1, characterized in that: The outer cylinder (601) and the inner cylinder (602) are both made of transparent acrylic material.

6. A visual acoustic emission ring shear instrument according to claim 1, characterized in that: The disc (701) also has a pressing sheet (7012); the pressing sheet (7012) is fixed to the upper surface of the disc (701) by means of bolts.

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