A device and method for adjusting the distance of bidirectional confining pressure loading of a rock sample to be drilled

Abstract

The present application relates to a kind of to be drilled rock sample bidirectional confining pressure loading distance adjustable device and adjusting method, belong to drilling technology field, the device includes long strip ground platform, distance adjusting assembly is arranged on ground platform, the assembly is by multiple confining pressure loading units equidistant array splicing along the same axis, each confining pressure loading unit is internally provided with support, support outside and top are respectively connected with the horizontal pressure frame with transverse loading oil cylinder and the vertical pressure frame with longitudinal loading oil cylinder, multiple unit internal filling rock is connected head to tail to form continuous test section, longitudinal and transverse oil cylinder output end vertically meets rock surface to exert bidirectional static pressure.The present application can dynamically change overall confining pressure loading total length by independently adding or removing the number of confining pressure loading unit, solve the problem that drilling test distance is not adjustable due to the limitation of assembly space in indoor micro-drill test, provide effective platform for obtaining long distance drilling parameters.

Description

Technical Field

[0001] This invention relates to the field of drilling technology, specifically to a device and method for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled. Background Technology

[0002] In the fields of geological exploration and underground engineering, rotary drilling technology is an important means of obtaining information about underground rock strata and developing resources. To conduct in-depth research on key technologies such as adaptive drilling processes, in-hole parameter inversion, and coal-rock interface identification, researchers typically need to conduct numerous simulated drilling tests using indoor rotary drilling test benches. In these tests, to accurately reflect the complex stress state of deep underground rock strata, a certain confining pressure load must be applied to the target rock sample to be drilled, placing the rock under stress conditions consistent with the actual geological environment, thereby obtaining accurate engineering mechanics data and drilling parameters.

[0003] In existing indoor rotary drilling tests, confining pressure loading on the rock to be drilled typically relies on a one-piece, fixed confining pressure loading chamber or a rigid, integral bearing platform. During operation, the tester places a pre-processed, fixed-size individual rock sample into the loading chamber and applies longitudinal or lateral pressure to the outer end face of the rock using hydraulic cylinders or mechanical push rods arranged around the perimeter. Once the rock has stabilized under stress, the external drilling equipment is activated, driving the drill bit to cut into the compressed rock along a predetermined axis for rotary cutting and parameter acquisition.

[0004] However, existing indoor micro-drilling test equipment has significant limitations in practical engineering applications. Its fixed structural design restricts internal assembly space, making it impossible to adjust the total loading length of the rock according to specific test requirements. Because traditional confining pressure loading devices typically use a single-unit load-bearing frame with fixed dimensions, the equipment cannot extend its physical length when facing test tasks with longer drilling depths, thus preventing it from providing rock samples of varying lengths. This physical defect of a fixed and unadjustable loading distance directly limits the effective drilling distance in the drilling direction, making existing indoor test benches unable to flexibly meet the working conditions of long-distance continuous micro-drilling tests, and hindering the accurate inversion and research of drilling parameters related to deep rock formations. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a device and method for adjusting the bidirectional confining pressure loading distance of rock samples to be drilled. This invention aims to solve the problem that existing indoor micro-drilling test devices, due to limited internal assembly space and a fixed overall structure, cannot dynamically adjust the total length of the confining pressure loading of the rock samples to be drilled according to test requirements, thereby limiting the effective distance of a single rotary drilling and failing to flexibly cope with long-distance continuous micro-drilling test conditions.

[0006] To achieve the above objectives, the present invention provides the following technical solution: The first aspect proposes a device for adjusting the bidirectional confining pressure loading distance of the rock sample to be drilled, including: Ground platform, drilling equipment, and distance adjustment components; The drilling device is collinear with the side of the ground platform; a distance adjustment component is provided on the ground platform; The distance adjustment component includes a confining pressure loading unit; The confining pressure loading unit includes a support, a transverse pressure frame, a transverse loading cylinder, a longitudinal pressure frame, and a longitudinal loading cylinder. The support is fixedly connected to the top of the platform. The transverse pressure frame is fixedly connected to the outer end face of the support. The transverse loading cylinder is fixedly connected to the inner side wall of the transverse pressure frame. The longitudinal pressure frame is fixedly connected to the top surface of the transverse pressure frame. The longitudinal loading cylinder is fixedly connected to the inner top of the longitudinal pressure frame. The bottom end of the longitudinal loading cylinder and the side end of the transverse loading cylinder are both attached to a rock.

[0007] Preferably, the confining pressure loading unit is provided in multiple sets, and the multiple sets of confining pressure loading units are arranged at intervals along the drilling axis of the drilling device, and adjacent confining pressure loading units are arranged parallel to each other.

[0008] Preferably, the internal structures of the multiple sets of confining pressure loading units are all the same, and the longitudinal extension central axes of the multiple sets of confining pressure loading units are collinearly distributed.

[0009] Preferably, the multiple sets of confining pressure loading units are arranged in an equidistant array on the top bearing surface of the platform. (Corresponding to claim 4) Preferably, the interiors of the multiple sets of confining pressure loading units each contain corresponding rocks.

[0010] Preferably, multiple rocks are connected end to end along the drilling axis to form a continuous pressure rock section with a continuous through-test cross section.

[0011] Preferably, each of the multiple sets of confining pressure loading units is an independent module that is bolted to the ground platform.

[0012] Preferably, the longitudinal pressure extension axis of the longitudinal loading cylinder and the lateral pressure extension axis of the transverse loading cylinder are mutually perpendicular and intersecting in three-dimensional space.

[0013] Preferably, the output end face of the longitudinal loading cylinder and the output end face of the transverse loading cylinder together surround and cover the periphery of the rock.

[0014] Preferably, the longitudinal pressure frame covers the top periphery of the transverse pressure frame.

[0015] Preferably, the transverse pressure frame and the longitudinal pressure frame constitute a rigid reaction force support structure. The transverse pressure frame is used to provide a lateral static reaction force support point for the output thrust of the transverse loading cylinder, and the longitudinal pressure frame is used to provide a vertical static reaction force support point for the output thrust of the longitudinal loading cylinder.

[0016] Preferably, the inner bottom surface of the transverse pressure frame is in direct contact with the outer bottom surface of the rock, forming a limiting and supporting fit for the bottom of the rock in the vertical direction.

[0017] Preferably, the top surface of the ground platform is provided with a linear guide groove along the drilling main axis, and the bottom of the support of each confining pressure loading unit is fixedly provided with a positioning guide shoe. The positioning guide shoe is fitted into the linear guide groove to form a linear guide limiting structure along the drilling main axis. The support and the ground platform are fastened together by bolts.

[0018] Preferably, a pressure equalization buffer plate is provided between the output end face of the longitudinal loading cylinder and the top surface of the rock, and between the output end face of the transverse loading cylinder and the side surface of the rock.

[0019] Preferably, the inner side of the pressure equalization buffer plate is fitted and covered to the pressure-bearing surface of the rock, and the outer side of the pressure equalization buffer plate abuts against the output end face of the corresponding hydraulic cylinder.

[0020] The second aspect proposes an adjustment method for an adjustable device for bidirectional confining pressure loading distance of a rock sample to be drilled, applicable to the adjustable device for bidirectional confining pressure loading distance of a rock sample to be drilled as proposed in the first aspect. The adjustment method includes the following steps: S1, Establish the horizontal plane fixed installation reference state of the ground platform; S2, under the horizontal plane fixed installation reference state established in S1, a coaxial parallel array assembly distribution state of multiple sets of confining pressure loading units is sequentially established on the top of the ground platform; S3, based on the coaxial parallel array assembly distribution state established in S2, a continuous and tight splicing contact state of multiple rocks is jointly established inside multiple sets of confining pressure loading units, forming a continuous rock segment that matches the total length of each unit; S4, for the continuous rock segment formed in S3, control the establishment of a horizontal collinear alignment between the front end center of the drilling device and the rock center inside the first confining pressure loading unit; S5, under the horizontal collinear alignment and engagement state described in S4, control the output ends of the longitudinal loading cylinder and the transverse loading cylinder to be in the push-fitting position, and establish a bidirectional vertical static compression constraint transmission state on the entire rock surface. S6. Maintain the bidirectional vertical static compression constraint transmission state established in S5 for parameter verification. After the single test ends and the state is released, change the total length of the array by individually adding or removing the number of the confining pressure loading units, and establish a dynamic length adjustment matching state adapted to the target loading distance.

[0021] This invention provides a device and method for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled. It has the following beneficial effects: 1. This invention arranges multiple independent confining pressure loading units along a coaxial axis on the top of a ground platform, and uses the rock filled inside each unit to form a continuous test section. This allows test personnel to independently add or remove the number of confining pressure loading units according to the distance requirements of the specific drilling test, achieving a dynamic and controllable adjustment effect on the total length of the bidirectional confining pressure loading of the rock sample to be drilled. This solves the engineering application problem that existing indoor micro-drilling test devices cannot provide rock samples of different lengths under pressure due to limited internal assembly space.

[0022] 2. This invention sets up mutually perpendicular longitudinal and transverse loading cylinders inside each confining pressure loading unit, and controls the output end face of the two sets of cylinders to keep perpendicular to the surface of the rock filled at the center position. This allows each rock segment to receive static compressive constraint forces in both the longitudinal and transverse directions simultaneously, achieving the physical testing effect of simulating real underground bidirectional geostress conditions in an indoor test bench environment. This ensures that the entire rock segment, which is continuously spliced ​​over a long distance, always maintains a stable alignment and clamping state when facing the continuous rotary drilling of the front drill bit.

[0023] 3. This invention uses a ground platform as the underlying unified horizontal bearing foundation, and controls the central axis of multiple confining pressure loading units, including supports and longitudinal and transverse pressure frames, to be horizontally collinearly aligned with the main propulsion axis of the end drilling device. This avoids axial positional offset between multiple independently clamped rock sections caused by assembly, and achieves a strict limiting and guiding effect on the overall structure of the multi-unit combined array when subjected to continuous unilateral rotary drilling thrust. This ensures the continuity of the stress state of each rock section and the accuracy of test data acquisition during long-distance micro-drilling tests. Attached Figure Description

[0024] Figure 1 This is a front view of the overall structure of the present invention; Figure 2 This is a schematic diagram of the confining pressure loading unit structure of the present invention; Figure 3This is a schematic diagram of the overall working state of the device of the present invention during confining pressure loading and rotary drilling tests. Figure 4 This is a schematic flowchart of the adjustment method of the present invention.

[0025] Among them, 1. Ground platform; 2. Confining pressure loading unit; 6. Drilling device; 7. Support; 8. Rock; 9. Longitudinal loading cylinder; 10. Longitudinal pressure frame; 11. Lateral loading cylinder; 12. Lateral pressure frame. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Example: Please see the appendix Figure 1 , Figure 3 , Figure 4 This embodiment includes a ground platform 1. The overall outer contour of the ground platform 1 is a long strip thick plate support structure. The top bearing surface of the ground platform 1 is a horizontal flat surface structure. The ground platform 1 provides a stable and absolutely horizontal bearing foundation for the entire multi-unit system. A drilling device 6 is set at the collinear position on the side of the ground platform 1. The overall contour of the drilling device 6 is a horizontal long strip machine structure. The drilling device 6 is used to perform rotary drilling operations on the target rock 8 during the test phase. A distance adjustment component is set on the ground platform 1. The distance adjustment component is used to realize the dynamic splicing and increase / decrease of the total length of macroscopic loading.

[0028] Please see the appendix Figure 1 , Figure 2 , Figure 4The distance adjustment component includes multiple sets of confining pressure loading units 2, which are arranged at intervals along the drilling axis of the drilling device 6, and adjacent confining pressure loading units 2 are arranged parallel to each other. The internal structures of the multiple confining pressure loading units 2 are identical to ensure assembly uniformity. These units are arranged in a linearly symmetrical array with equal intervals on the top bearing surface of the platform 1, and their longitudinal central axes are collinearly aligned. Each confining pressure loading unit 2 can be independently added to or removed from the modular unit structure, thus enabling the device to adjust the loading length along the axis. The front working docking surface of the drilling device 6 faces the center of the internal hollow area of ​​the first confining pressure loading unit 2. The horizontal inward extension direction of the drilling device 6 is parallel and aligned with the linear collinear arrangement of the multiple confining pressure loading units 2, ensuring precise alignment of the drilling axis and the unit assembly axis. A linear guide groove is formed on the top surface of the platform 1 along the main drilling axis. Positioning guide shoes are fixedly installed at the bottom of the supports 7 of each confining pressure loading unit 2, fitting into the linear guide grooves to form a linear guiding and limiting structure along the main drilling axis. The supports 7 are fastened to the platform 1 with bolts. Please see the appendix Figure 2 , Figure 4 Inside each confining pressure loading unit 2, taking one confining pressure loading unit 2 as an example, each confining pressure loading unit 2 includes a support 7, which is fixedly connected to the top of the ground platform 1. The support 7 has an overall shape of a cubic hollow box bearing structure, and plays a core foundational supporting role. A transverse pressure frame 12 is fixedly connected to the outer end face of the support 7. The transverse pressure frame 12 has an overall shape of a C-shaped encircling side frame structure, and provides a rigid reaction force application point for the lateral hydraulic components. A transverse loading cylinder 11 is fixedly connected to the inner wall of the transverse pressure frame 12. The transverse loading cylinder 11 has an overall shape of... The structure is a horizontally suspended cylindrical structure. A transverse loading cylinder 11 outputs horizontal confining pressure. A longitudinal pressure frame 10 is fixedly connected to the top surface of the transverse pressure frame 12, and the longitudinal pressure frame 10 covers the top periphery of the transverse pressure frame 12. The overall shape of the longitudinal pressure frame 10 is an inverted U-shaped load-bearing top frame structure. The transverse pressure frame 12 and the longitudinal pressure frame 10 form a rigid reaction support structure. The transverse pressure frame 12 provides lateral static reaction support points for the output thrust of the transverse loading cylinder 11, and the longitudinal pressure frame 10 provides vertical static reaction support points for the output thrust of the longitudinal loading cylinder 9. The longitudinal loading cylinder 9 is fixedly connected to the inner top of the longitudinal pressure frame 10. The overall shape of the longitudinal loading cylinder 9 is a vertically suspended cylindrical structure, and the longitudinal loading cylinder 9 outputs vertical confining pressure.

[0029] Please see the appendix Figure 2 , Figure 4The bottom end of the longitudinal loading cylinder 9 and the side end of the transverse loading cylinder 11 together enclose the periphery of the rock 8. The overall outer contour of the rock 8 is a regular hexahedral block structure. The internal cavity size of the transverse pressure frame 12 is adapted to the outer contour size of the rock 8. The inner bottom surface of the transverse pressure frame 12 and the outer bottom surface of the rock 8 form a tight contact limiting fit support state. The vertical installation center line of the longitudinal loading cylinder 9 and the top center point of the rock 8 are on the same vertical axis. The bottom end face of the longitudinal loading cylinder 9 and the top end face of the rock 8 form a vertical static abutment. In the fit and connection state, the horizontal installation center line of the transverse loading cylinder 11 is on the same horizontal axis as the side center point of the rock 8. The lateral output end face of the transverse loading cylinder 11 forms a vertical static abutment fit and connection state with the side wall end face of the rock 8. To optimize the pressure state, pressure equalization buffer plates are sandwiched between the output end face of the longitudinal loading cylinder 9 and the top surface of the rock 8, and between the output end face of the transverse loading cylinder 11 and the side surface of the rock 8. The inner side of the pressure equalization buffer plate fits and covers the pressure-bearing surface of the rock 8, and the outer side of the pressure equalization buffer plate abuts against the output end face of the corresponding cylinder. The longitudinal pressure extension axis of the longitudinal loading cylinder 9 and the transverse pressure extension axis of the transverse loading cylinder 11 are perpendicularly intersecting in the three-dimensional space, and the two are symmetrically configured in a one-to-one manner, together enclosing the periphery of the rock 8.

[0030] Please see the appendix Figure 1 Ultimately, the total length of the multiple sets of confining pressure loading units 2 combined and spliced ​​along the same axis is equal to the total extension length of the multiple rocks 8 coaxially spliced ​​inside the multiple sets of confining pressure loading units 2.

[0031] Working principle: Equipment foundation construction and module layout: During operation, the ground platform 1 is first placed stably on the test site to ensure that the bearing surface of the ground platform 1 is level, providing a foundation support for all subsequent components. Then, according to the total loading length required for this rotary drilling test, the operator places the corresponding number of loading modules on the ground platform 1 in sequence. For example, multiple sets of confining pressure loading units 2 are arranged in sequence. During this process, the positioning guide shoes and linear guide grooves are used for sliding cooperation, and the supports 7 at the bottom of each unit are fixed to the ground platform 1 with bolts. It is also ensured that the internal cavities of all loading units are on the same central axis to achieve precise alignment of the assembly perspective.

[0032] Sample loading and equipment alignment: After the frame is assembled and fixed, multiple rocks 8 are placed inside the transverse pressure frame 12 of each confining pressure loading unit 2. The multiple rocks 8 are tightly fitted together along the central axis to form a continuous long-distance rock 8 test sample. Then, the drilling device 6 is adjusted and positioned so that the working part at the front end of the drilling device 6 is facing the hollow end face of the first confining pressure loading unit 2, ensuring that the advancing direction of the drilling device 6 coincides with the central horizontal axis formed by the multiple rocks 8.

[0033] Bidirectional loading and drilling test: After the test preparation is complete, the hydraulic system in each unit is started synchronously. The longitudinal loading cylinder 9 located at the top of the longitudinal pressure frame 10 extends its piston rod downward to press the top of the rock 8; the transverse loading cylinder 11 located on the side of the transverse pressure frame 12 extends its piston rod inward to press the side wall of the rock 8. Through the synchronous force of the two cylinders, a static clamping force perpendicular to each other is applied to the entire rock 8, thereby simulating the bidirectional geostress condition in the deep underground under the test bench environment. After the loading is stable, the drilling device 6 is started to carry out drilling and parameter acquisition operations on the long-distance rock 8 under pressure.

[0034] Test reset and dynamic adjustment of loading distance: After a single batch of tests is completed, all longitudinal loading cylinders 9 and transverse loading cylinders 11 are depressurized and retracted to release the pressure constraint on the rock 8 and clean up the damaged test samples. When subsequent tests require changes to the total drilling distance, the operator does not need to replace large equipment. He only needs to add multiple sets of confining pressure loading units 2 in series at the end of the ground platform 1, or remove some of the redundant confining pressure loading units 2 to quickly change the total physical length of the entire device. After the length is adjusted and a new number of rocks 8 are reloaded, drilling tests under different loading distance conditions can be carried out.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled, characterized in that, include: Ground platform (1), drilling device (6), and distance adjustment assembly; The drilling device (6) is collinear with the side of the ground platform (1); a distance adjustment component is provided on the ground platform (1); The distance adjustment component includes a confining pressure loading unit (2); The confining pressure loading unit (2) includes a support (7), a transverse pressure frame (12), a transverse loading cylinder (11), a longitudinal pressure frame (10), and a longitudinal loading cylinder (9). The support (7) is fixedly connected to the top of the platform (1), the transverse pressure frame (12) is fixedly connected to the outer end face of the support (7), the transverse loading cylinder (11) is fixedly connected to the inner side wall of the transverse pressure frame (12), the longitudinal pressure frame (10) is fixedly connected to the top surface of the transverse pressure frame (12), the longitudinal loading cylinder (9) is fixedly connected to the inner top of the longitudinal pressure frame (10), and the bottom end of the longitudinal loading cylinder (9) and the side end of the transverse loading cylinder (11) are together fitted with a rock (8).

2. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 1, characterized in that: The confining pressure loading unit (2) is provided in multiple sets. The multiple sets of confining pressure loading units (2) are arranged at intervals along the drilling axis of the drilling device (6), and adjacent confining pressure loading units (2) are arranged in parallel to each other.

3. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 2, characterized in that: The internal structures of the multiple sets of confining pressure loading units (2) are all the same, and the longitudinal extension central axes of the multiple sets of confining pressure loading units (2) are collinearly distributed.

4. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 2, characterized in that: Multiple sets of the confining pressure loading units (2) are arranged in an equidistant array on the top bearing surface of the ground platform (1).

5. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 2, characterized in that: The interior of each of the multiple sets of confining pressure loading units (2) contains corresponding rocks (8).

6. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 5, characterized in that: Multiple rocks (8) are connected end to end along the drilling axis to form a continuous pressure rock section with a continuous through test section.

7. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 2, characterized in that: Each of the multiple confining pressure loading units (2) is an independent module that is bolted to the ground platform (1).

8. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 1, characterized in that: The longitudinal pressure extension axis of the longitudinal loading cylinder (9) and the lateral pressure extension axis of the transverse loading cylinder (11) are mutually perpendicularly intersecting in three-dimensional space.

9. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 8, characterized in that: The output end face of the longitudinal loading cylinder (9) and the output end face of the transverse loading cylinder (11) together surround and cover the periphery of the rock (8).

10. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 1, characterized in that: The longitudinal pressure frame (10) covers the top periphery of the transverse pressure frame (12).

11. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 10, characterized in that: The transverse pressure frame (12) and the longitudinal pressure frame (10) constitute a rigid reaction force support structure. The transverse pressure frame (12) is used to provide a lateral static reaction force support point for the output thrust of the transverse loading cylinder (11), and the longitudinal pressure frame (10) is used to provide a vertical static reaction force support point for the output thrust of the longitudinal loading cylinder (9).

12. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 1, characterized in that: The inner bottom surface of the transverse pressure frame (12) is in direct contact with the outer bottom surface of the rock (8), forming a limiting and supporting state for the bottom of the rock (8) in the vertical direction.

13. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 2, characterized in that: The top surface of the platform (1) is provided with a linear guide groove along the drilling main axis. The bottom of the support (7) of each confining pressure loading unit (2) is fixedly provided with a positioning guide shoe. The positioning guide shoe is fitted into the linear guide groove to form a linear guide limiting structure along the drilling main axis. The support (7) and the platform (1) are fastened together by bolts.

14. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 1, characterized in that: A pressure equalization buffer plate is provided between the output end face of the longitudinal loading cylinder (9) and the top surface of the rock (8), and between the output end face of the transverse loading cylinder (11) and the side surface of the rock (8).

15. The device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled according to claim 14, characterized in that: The inner side of the pressure equalization buffer plate is attached to and covers the pressure surface of the rock (8), and the outer side of the pressure equalization buffer plate abuts against the output end face of the corresponding oil cylinder.

16. A method for adjusting a device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled, applied to the device for adjusting the bidirectional confining pressure loading distance of a rock sample to be drilled as described in any one of claims 1 to 15, characterized in that, The adjustment method includes the following steps: S1, establish the horizontal plane fixed installation reference state of the ground platform (1); S2, under the horizontal plane fixed installation reference state established in S1, a coaxial parallel array assembly distribution state of multiple sets of confining pressure loading units (2) is sequentially established on the top of the ground platform (1); S3, based on the coaxial parallel array assembly distribution state established in S2, a continuous and tight splicing contact state of multiple rocks (8) is jointly established inside multiple sets of confining pressure loading units (2), forming a continuous rock segment that matches the total length of each unit; S4, for the continuous rock segment formed in S3, control the establishment of a horizontal collinear alignment between the front end center of the drilling device (6) and the center of the rock (8) inside the first confining pressure loading unit (2); S5, under the horizontal collinear alignment and cooperation state described in S4, control the output ends of the longitudinal loading cylinder (9) and the transverse loading cylinder (11) to be in the push-fit position, and establish a bidirectional vertical static compression constraint transmission state on the surface of the entire rock (8). S6, maintain the bidirectional vertical static compression constraint transmission state established in S5 for parameter verification. After the single test ends and the state is released, change the total length of the array by adding or removing the number of the confining pressure loading unit (2) separately, and establish a dynamic length adjustment matching state adapted to the target loading distance.

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