CN-121994583-A - Fracture instability test device and method equipped with industrial CT scanning

CN121994583ACN 121994583 ACN121994583 ACN 121994583ACN-121994583-A

Abstract

The invention discloses a fracture instability test device and method equipped with industrial CT scanning, belonging to the technical field of rock mechanics test, in order to analyze the problem of fracture zone friction instability induced by high-pressure fluid injection by adopting more comprehensive data, the fracture instability test device with the industrial CT scanning comprises a core holder (1), a ray source (2) and a detector (3), wherein a test sample (4) can be clamped in the core holder (1), and rays emitted by the ray source (2) can pass through the test sample (4) and irradiate the detector (3). The fracture instability test device and method with industrial CT scanning can realize staged CT scanning work in the friction instability test process, collect signal waveforms of fracture surfaces in the sliding instability process, and realize full-period and full-aspect data recording of the friction instability test of the fracture zone induced by high-pressure fluid injection.

Inventors

SANG YU
ZENG BO
HUANG HAOYONG
LI YADING
Feng Jiangrong
CHEN JUNJIE

Assignees

中国石油天然气股份有限公司

Dates

Publication Date: 20260508
Application Date: 20241107

Claims (10)

1. The utility model provides a be equipped with fracture unstability test device of industry CT scanning, a serial communication port, be equipped with fracture unstability test device of industry CT scanning includes rock core holder (1), ray source (2) and detector (3), rock core holder (1) are located between ray source (2) and detector (3), rock core holder (1) contain loading barrel (16), go up pressure cap (13) and push down cap (19), loading barrel (16) are upright state, the fixed cover in upper end of loading barrel (16) in lower part of going up pressure cap (13), the fixed cover in lower extreme of loading barrel (16) in upper portion of push down cap (19) is located, go up pressure cap (13) endotheca and be equipped with loading piston (12) and last end cap (15) that set up from top to bottom, push down cap (19) endotheca is equipped with down end cap (18), go up end cap (15) and down end cap (18) can centre gripping test sample (4), the ray that ray source (2) launched can pass test sample (4) and detector (3).
2. The fracture instability test apparatus equipped with industrial CT scanning according to claim 1, wherein the loading cylinder (16) comprises a cylinder wall (1601) and an inner space (1602), the inner space (1602) comprises a rubber sleeve (17), the upper end of the rubber sleeve (17) is sleeved outside the lower end of the upper plug (15), the lower end of the rubber sleeve (17) is sleeved outside the upper end of the lower plug (18), the rubber sleeve (17) can be sleeved outside the test sample (4), an annular cavity (1603) is formed between the rubber sleeve (17) and the loading cylinder (16), and rays emitted by the ray source (2) are X rays.
3. The fracture instability test device with industrial CT scanning according to claim 1, wherein the upper pressing cap (13) is of an upright cylindrical structure, the upper pressing cap (13) is in threaded connection with the loading cylinder (16), the upper part of the upper pressing cap (13) is located outside the loading cylinder (16), an upper axial through hole (1301) and a radial through hole (1302) are formed in the upper pressing cap (13), the loading piston (12) and the upper plug (15) are located in the upper axial through hole (1301), and the radial through hole (1302) is located outside the loading cylinder (16).
4. A fracture instability test apparatus equipped with an industrial CT scan according to claim 3, wherein a pressure sensor (14) is arranged between the loading piston (12) and the upper plug (15), the pressure sensor (14) is capable of measuring the pressure applied by the loading piston (12) to the upper plug (15), the position of the pressure sensor (14) corresponds to the position of the radial through hole (1302), and the pressure sensor (14) is capable of passing through the radial through hole (1302).
5. A fracture instability test apparatus equipped with an industrial CT scan according to claim 3, wherein a loading top cover (11) is connected to the outside of the upper end of the upper pressure cap (13), a piston loading chamber (1101) is formed between the loading top cover (11) and the loading piston (12), an axial pressure pressurizing channel (1102) is included in the loading top cover (11), and pressure liquid can enter the piston loading chamber (1101) through the axial pressure pressurizing channel (1102) and move the loading piston (12) downward.
6. The industrial CT scan equipped fracture destabilization testing device according to claim 5, further comprising an axial pressure loading system containing an electric hydraulic pump having a hydraulic output port in communication with an axial pressure pressurization channel (1102), the electric hydraulic pump containing a servo motor.
7. The fracture instability test device with industrial CT scanning according to claim 2, wherein the pressing cap (19) is of an upright cylindrical structure, the pressing cap (19) is in threaded connection with the loading cylinder (16), the lower part of the pressing cap (19) is located outside the loading cylinder (16), the pressing cap (19) is internally provided with a lower axial through hole (1901), the lower plug (18) is located inside the lower axial through hole (1901), a fixing ring (110) is sleeved between the pressing cap (19) and the lower plug (18), the fixing ring (110) is in threaded connection with the pressing cap (19), the fixing ring (110) can prevent the lower plug (18) from moving downwards, a confining pressure pressurizing channel (1902) is arranged in the pressing cap (19), the upper end of the confining pressure pressurizing channel (1902) is communicated with the annular cavity (1603), the lower end of the confining pressure pressurizing channel (1902) is located at the lower part of the side peripheral surface of the pressing cap (19), and the lower end of the confining pressure pressurizing channel (1902) is located outside the loading cylinder (16).
8. The fracture instability test apparatus equipped with industrial CT scanning according to claim 3, wherein the upper plug (15) comprises an upper mounting hole (1501) and an upper pressing channel (1502), the upper end of the upper mounting hole (1501) is in an open state, the lower end of the upper mounting hole (1501) is in a closed state, the upper end of the upper plug (15) is provided with a radial notch (1503), the radial notch (1503) is communicated with the upper mounting hole (1501), the lower end of the upper pressing channel (1502) is positioned on the lower end face of the upper plug (15), the upper end of the upper pressing channel (1502) is positioned on the upper part of the side peripheral face of the upper plug (15), the upper end of the upper pressing channel (1502) and the radial notch (1503) are both positioned in the upper axial through hole (1301), the lower plug (18) comprises a lower mounting hole (1801) and a lower pressing channel (1802), the lower end of the lower mounting hole (1801) is in an open state, the upper end of the lower mounting hole (1801) is in a closed state, the upper end of the lower pressing channel (1802) is positioned on the lower end face of the lower plug (1802) is positioned on the upper end face of the lower plug (15), and the upper end face (1802) is positioned on the lower end face (1801) is positioned on the lower end face of the lower plug (1801).
9. The fracture instability test apparatus equipped with industrial CT scanning according to claim 7, wherein the core holder (1) further comprises a base (111), the base (111) comprises an upper base plate (11101) and a lower base plate (11102) which are arranged at intervals up and down, the upper base plate (11101) is in a circular structure, the lower cap (19) is located on the upper base plate (11101), the upper base plate (11101) is sleeved outside the fixing ring (110), the upper base plate (11101) and the lower base plate (11102) are connected through a plurality of supporting legs (11103), and the plurality of supporting legs (11103) are arranged at intervals along the circumference of the upper base plate (11101).
10. The fracture instability test method for the equipped industrial CT scan is characterized in that the fracture instability test method for the equipped industrial CT scan adopts the fracture instability test device for the equipped industrial CT scan according to claim 1, and the fracture instability test method for the equipped industrial CT scan sequentially comprises the following steps: step 1, mounting a test sample (4) between an upper plug (15) and a lower plug (18), and applying confining pressure and axial pressure to the test sample (4); Step 2, increasing the axle pressure of the test sample (4), observing the change trend of an axle pressure curve, and stopping loading the loading piston (12) when the axial stress increasing rate gradually slows down, wherein the test sample (4) reaches a critical slip unsteady state; And 3, injecting high-pressure fluid through the upper pressing channel (1502) or the lower pressing channel (1802), and enabling rays emitted by the ray source (2) to pass through the test sample (4) and irradiate the test sample to the detector (3), wherein the detector (3) receives the rays.

Description

Fracture instability test device and method equipped with industrial CT scanning Technical Field The invention relates to the technical field of rock mechanics tests, in particular to a fracture instability test device equipped with industrial CT scanning, and also relates to a fracture instability test method equipped with industrial CT scanning. Background The problem of friction instability of a fracture zone induced by high-pressure fluid injection is gradually focused, and in the process of knowing the friction instability of the fracture zone and a mechanical mechanism thereof induced by engineering operation, an important role is played by indoor tests, and the sliding characteristics of a fracture surface in nature can be obtained by analogy and other methods as the most basic and most common method. In the prior friction instability test of the fracture zone, a polycarbonate plate or organic glass is mainly adopted for carrying out the test, the homogeneous materials are obviously different from rock materials, on the other hand, the confining pressure system and the fluid pressure system are difficult to separate relatively in the test process, the confining pressure and the fluid pressure of the test environment are difficult to control accurately, and in addition, the traditional test method lacks of visual research of the test process and collection of acoustic emission data in the sliding process of the test process. Disclosure of Invention In order to analyze the problem of friction instability of a fracture zone caused by high-pressure fluid injection by adopting more comprehensive data, the invention provides a fracture instability test device and a fracture instability test method provided with industrial CT scanning, wherein the fracture instability test device and the fracture instability test method provided with industrial CT scanning can realize staged CT scanning work in the friction instability test process, collect signal waveforms of fracture surfaces in the sliding instability process, and can realize data recording of all time periods and all aspects of the friction instability test of the fracture zone caused by high-pressure fluid injection. The technical scheme adopted for solving the technical problems is as follows: The utility model provides a fracture unstability test device of being equipped with industry CT scanning, including rock core holder, ray source and detector, rock core holder is located between ray source and the detector, rock core holder contains the loading barrel, go up the pressure cap and push down the cap, the loading barrel is upright state, go up the fixed cover in the lower part of pressure cap and locate the upper end of loading barrel, the fixed cover in the lower extreme of loading barrel of upper portion of pressure cap is located, go up the pressure cap endotheca and be equipped with loading piston and the last end cap that sets up from top to bottom, it is equipped with the end cap down to push down the cap endotheca, it can the centre gripping test sample to go up the end cap and the end cap down, the ray that the ray source launched can pass test sample and the orientation detector. The fracture instability test method for the equipped industrial CT scan adopts the fracture instability test device for the equipped industrial CT scan, and the fracture instability test method for the equipped industrial CT scan sequentially comprises the following steps: step 1, mounting a test sample between an upper plug and a lower plug, and applying confining pressure and axial pressure to the test sample; step 2, increasing the axial pressure of the test sample, observing the change trend of an axial pressure curve, and stopping loading by the loading piston when the axial stress increasing rate gradually slows down, wherein the test sample reaches a critical slip unstability state; and 3, injecting high-pressure fluid through the upper pressing channel or the lower pressing channel, and enabling rays emitted by the ray source to penetrate through the test sample and irradiate to the detector, wherein the detector receives the rays. The invention has the advantages that by means of industrial CT scanning, acoustic receiving and the like, the staged evolution result scanning of the test process can be realized, the signal waveform of the fracture surface in the sliding instability process can be collected, the full-time and full-aspect data recording of the friction instability test of the fracture zone induced by high-pressure fluid injection can be realized, the means of digitalization and geophysics are applied to the rock mechanics test result processing, and the comprehensiveness of test data and analysis results is improved. Drawings The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and togeth