CN-122016534-A - Device and method for testing anisotropic mechanical properties of strong heterogeneous rock

Abstract

The invention discloses a testing device and a testing method for anisotropic mechanical properties of a strong heterogeneous rock, comprising a rotatable rock sample fixing device, a workbench and a sliding track, wherein a scratch cutter control and data monitoring system, a workbench and a sliding track device main body are fixed on a tabletop and are convenient to support and move, a sliding scratch system moving track supports the sliding scratch system to move left and right, the rotatable rock sample fixing device is positioned on the left side above the tabletop and can fix the position of a rock sample and change the rock scratch angle, the scratch cutter control and data monitoring system is positioned on the right side of the tabletop and is connected with the sliding track, the sliding scratch system can scratch the rock, and the data monitoring system can monitor and collect tangential force data born by a cutter head and displacement data of the cutter head in real time.

Inventors

• ZHAO PENGFEI
• ZHANG XU
• FAN XIANGYU
• CHEN LE
• ZHAO HAITAO
• ZHANG QIANGUI
• CHEN YUFEI
• WANG YUNCHANG
• HUANG QIANJUN

Assignees

• 西南石油大学

Dates

Publication Date

20260512

Application Date

20260212

Claims (5)

1. 1. The device for testing the anisotropic mechanical properties of the strong heterogeneous rock is realized by adopting an adjustable multi-angle rock scratching device, and is characterized by comprising the following steps of: S1, processing a rock into a cuboid sample, wherein the upper surface of the rock sample is a flat surface and is perpendicular to a weak structural surface of the rock for scratch experiments, the length of the rock sample (20) is between 15cm and 30cm, the width is between 10cm and 25cm, and the height is between 5cm and 13 cm; s2, photographing a sample before an experiment, rotating a fixing device to enable a center line on the device to be aligned to a target angle, screwing up 4 outer ring fixing screws, placing a processed rock sample (20) on the fixing device, placing a supporting block (7) on a base if the height of the rock sample (20) is too low, enabling the upper surface of the rock sample (20) to exceed four baffles, simultaneously observing the positions of the upper surface of the rock sample (20) and a cutter head (17), enabling the cutter head (17) to score the rock sample (20), adjusting the size of the fixing device, and screwing up the fixing screws of the 4 baffles after the fixing device is just attached to the sample; s3, starting the machine by using a computer, observing the distance between the blade and the rock sample, and resetting the blade by using the computer after the machine moves to the end; S4, starting by using a computer, resetting and repeating the operation after the cutter head (17) is completely scratched for one time, observing data on the computer, recording data of scratch length, scratch depth, shearing strength and tensile strength after continuous data appear, and restarting the cutter head (17) for three times; S5, resetting the cutter head (17) after the test is finished, taking a sample, photographing and recording the position of the sample to be scored, recording the data of the scratch length, the scratch depth, the shearing strength and the tensile strength, and calculating the compressive strength of each anisotropic scratch on the same rock obtained by the test by using a rock anisotropic compressive strength formula; The compressive strength of the rock anisotropy obtained from the scratch and the rock anisotropy obtained from the following formula; ; wherein: Is the anisotropic compressive strength of rock; is the maximum value of anisotropic compressive strength of rock under the angle obtained on the same rock face; is the minimum value of the anisotropic compressive strength of the rock at the angle obtained on the same rock face; Meanwhile, the anisotropy of a plurality of scratches positioned in a certain depth point can be further explored, the method is a method for calculating the anisotropy on the same rock based on continuous scratches, and if the scratches fall on a short side, the length can be calculated and expressed according to the following formula; ; wherein: a sampling line segment when the scratch angle is 0 degrees; Scratch starting point At different edges and with a scratch angle of Sampling line segments at the time; Is that And (3) with An included angle between the two; If the scratch falls on the long side, the length can be calculated to be represented according to the following formula; ; wherein: a sampling line segment when the scratch angle is 0 degrees; For starting point of scratch Different edges and scratch angles of Sampling line segments at the time; Is in combination with Line segments parallel and on the long sides of the rock sample; Is that And (3) with An included angle between the two; The test device is utilized to carry out rock strength scratch tests of different angles of the rock, and the result shows that a small amount of rock samples (20) are prepared at low cost, rock strength data of any angle of 0-360 degrees are obtained on the same sample by adjusting the rotation angle of the fixing device, the fixing device is rotated to a corresponding position according to the required experimental angle, the angle can be selected at will of 0-360 degrees, the rock samples (20) are not required to be disassembled repeatedly, a large amount of time can be saved, the anisotropy of the rock is calculated finally, and the obtained data are compared and are matched with the data obtained by the rock strength scratch device.
2. 2. The device for testing anisotropic mechanical properties of a strongly heterogeneous rock according to claim 1, wherein the testing device comprises a rotatable rock sample fixture, a table and a sliding track, a scoring tool control and data monitoring system.
3. 3. The device for testing anisotropic mechanical properties of a strongly heterogeneous rock according to claim 2, characterized in that the rotatable rock sample fixing device consists of an outer base fixing screw (1), a front side baffle (2), a bearing base (3), a rear side baffle (4), a side baffle (5), side baffle fixing screws (6) and supporting blocks (7), the bearing base (3) being used for sample placement and fixing while being rotatable to corresponding angles, the front side baffle (2), the rear side baffle (4) and the side baffle (5) assisting in fixing the sample position, the side fixing screws being tightened on the respective baffle bases so that the baffles are fixed while fixing the rock sample (20), the outer base fixing screw (1) fixing the bearing base (3) after the bearing base (3) is rotated to a desired angle, the supporting blocks (7) being used for assisting in elevating the rock sample (20) with insufficient height while adjusting the height between the rock sample (20) and the cutter head (17).
4. 4. The testing device for anisotropic mechanical properties of strong heterogeneous rocks according to claim 2, wherein the sliding track and the supporting table surface are composed of a table top (8), a 360-degree angle dial (9), a driving motor (10), a sliding scratch system moving track (11), a sliding scratch system fixing base (12) and base fixing screws (13), the table top (8) is used for bearing the 360-degree angle dial (9) of the rotatable rock sample fixing device and is positioned on the outer ring of the rotatable rock sample fixing device and used for determining a rotation angle, the rotatable angle is 360 degrees, the driving motor (10) controllably adjusts the moving speed of the sliding scratch system to accelerate or reduce the sliding speed, the sliding scratch system moving track (11) enables the sliding scratch system to move on the sliding scratch system moving track (11), and the sliding scratch system fixing base (12) and the base fixing screws (13) fix the sliding scratch system on the sliding scratch system moving track (11).
5. 5. The device for testing anisotropic mechanical properties of strong heterogeneous rocks according to claim 2, wherein the slidable scoring system and the data monitoring system are composed of a transverse moving seat (14), a double-sided support (15), a cutter mounting seat (16), a cutter head (17), a computer (18) and a data acquisition unit (19), wherein the transverse moving seat (14) moves on a moving track (11) of the slidable scoring system so that the cutter head (17) can score, the double-sided support (15) supports the whole slidable scoring system and simultaneously enables the slidable scoring system and a rotatable rock sample fixing device not to interfere with each other, and simultaneously stabilizes the cutter head (17) in the scoring process, the cutter mounting seat (16) is used for mounting the cutter head (17), the cutter head (17) is provided with a sharp cutter head (17) and a blunt cutter head (17) to be replaced, and the computer (18) is connected with the data acquisition unit (19) so as to realize real-time monitoring and acquisition of tangential force data received by the cutter head (17) and displacement data of the cutter head (17).

Description

Device and method for testing anisotropic mechanical properties of strong heterogeneous rock Technical Field The invention belongs to the technical field of rock mechanical property testing, and particularly relates to a device and a method for testing anisotropic mechanical properties of a strong heterogeneous rock. Background The rock mechanical characteristics are important basic parameters in the fields of geotechnical engineering, oil and gas exploitation, geological disaster prevention and control and the like, the rock with weak structural surfaces such as bedding, cutting and tattooing has different compressive failure strength in different stress directions, anisotropic characteristics are presented, the necessary consideration factors for evaluating the rock mechanical characteristics are generally obtained through compressive strength tests under a plurality of angles of the rock, but the method needs a plurality of rock samples, has low sampling success rate of the rock with weak structural surfaces, causes the method to be time-consuming and labor-consuming and has limited precision, scratch test technology is used as an emerging rock mechanical parameter measuring method, and rapid development is obtained in the rock mechanical field due to the advantages of simple sample preparation, nondestructivity, high test efficiency and the like. In conclusion, the technology develops a device and a method for testing the anisotropic mechanical properties of the rock with strong heterogeneity, the anisotropy of the rock can be tested on a rock sample, the test adopts a small number of rock samples, the test process is simple and quick, and the device and the method have important theoretical value and engineering significance for evaluating the mechanical properties of the rock with the weak face structure. Disclosure of Invention The invention aims to solve the problem of rock mechanical anisotropy test with a complex weak face structure, and provides a device and a method for testing anisotropic mechanical properties of a strong heterogeneous rock, which can test uniaxial compressive strength of the same rock at different angles and evaluate the mechanical anisotropy of the rock. The invention provides an anisotropic mechanical property testing device of strong heterogeneous rock based on scratches, which mainly comprises a rotatable rock sample fixing device, a workbench, a sliding track, and a scratch cutter control and data monitoring system. The rotatable rock sample fixing device comprises an outer base fixing screw 1, a front side baffle plate 2, a bearing base 3, a rear side baffle plate 4, side baffle plates 5, side baffle plate fixing screws 6 and supporting blocks 7. The workbench and the sliding track comprise a tabletop 8,360-degree angle dial 9, a driving motor 10, a sliding scratch system moving track 11, a sliding scratch system fixing base 12 and base fixing screws 13. The slidable scoring system comprises a transverse moving seat 14, a double-sided bracket 15, a cutter mounting seat 16, a cutter head 17, a computer 18 and a data acquisition unit 19. Further, the rotatable rock sample fixing device comprises an outer base fixing screw 1, a front side baffle plate 2, a bearing base 3, a rear side baffle plate 4, a side baffle plate 5, side baffle plate fixing screws 6 and supporting blocks 7, wherein the bearing base 3 of the rotatable rock sample fixing device is used for placing and fixing a rock sample 20, the rock sample 20 with different angles is scored through the rotating base, the outer base fixing screw 1 is used for fixing the position after the bearing base 3 rotates, the front side baffle plate 2, the rear baffle plate and the side baffle plate 5 are used for jointly fixing the rock sample 20, the distance between the baffle plates can be adjusted to adapt to the rock sample 20 with different sizes, the side baffle plate fixing screws 6 are used for fixing the baffle plate positions after the baffle plates clamp the rock, and the supporting blocks 7 are used when the height of the rock sample 20 does not exceed the baffle plates, and meanwhile the vertical distance between the rock sample 20 and a cutter head 17 is adjusted, so that the upper surface of the rock sample 20 exceeds the baffle plate part and can be scored. Further, the workbench and the sliding track comprise a tabletop 8,360-degree angle dial 9, a driving motor 10, a sliding scratch system moving track 11, a sliding scratch system fixing base 12 and base fixing screws 13, wherein the driving motor 10 can control the sliding speed of the sliding scratch system to be controlled to be increased or reduced, the sliding scratch system moving track 11 can enable the sliding scratch system to move left and right, the tabletop 8 supports a rotatable rock sample fixing device, the sliding track and the sliding scratch system are hung on the lower portion of the tabletop, the sliding scratch system fixing base 12 and t