A device and method for conveniently installing a true triaxial seepage pressure head

Abstract

The application discloses a device and method for conveniently installing a true triaxial seepage pressure head. The device comprises a base unit, a motion execution unit and a clamping unit. The base unit provides a fixed base and frame with the test bench. The motion execution unit is composed of a vertical driving module and a horizontal driving module; the vertical driving module drives the clamping unit to rise and fall through adjusting the lead screw, and the horizontal driving module drives the clamping unit to move horizontally through at least one horizontal sliding rail. The clamping unit comprises a fixed table with a groove and a detachable clamping plate for clamping the seepage pressure head. The horizontal driving module can contain a lateral sliding rail constituting a three-sided guide to limit deflection; the clamping unit can be equipped with rubber pads, modular quick-change components or self-adaptive clamping jaws to adapt to different pressure heads. The installation method comprises clamping, rough positioning, visual fine positioning, force control docking and release withdrawal steps. The problems of low precision and poor efficiency in the traditional installation method are solved, and the rapid, accurate and automated installation of the seepage pressure head is realized.

Description

Technical Field

[0001] This invention belongs to the field of rock mechanics and geotechnical engineering testing technology, specifically relating to a device and method for conveniently installing a true triaxial seepage head. It is particularly designed for true triaxial seepage tests requiring high frequency, high precision, and high reliability, providing a stable experimental basis for studying the seepage characteristics of rocks under complex stress states. Background Technology

[0002] With the advancement of my country's deep resource development strategy, the large-scale utilization of underground space, and the rise of new underground engineering projects such as energy storage and hydrogen storage, the mechanical response and permeability characteristics of rocks under the coupled effects of complex three-dimensional stress and seepage have become core issues determining the safety and efficiency of engineering projects. Engineering practices such as water inrush in deep mining and hydraulic fracturing in shale gas extraction all require precise understanding of the seepage laws of rocks under true triaxial stress. As the core equipment for studying this problem, the testing accuracy of the true triaxial seepage test device directly affects the scientific nature and reliability of engineering design.

[0003] One of the core aspects of true triaxial seepage testing is the precise alignment of the seepage head with the rock sample. The alignment accuracy and installation stability of the head and sample directly determine the sealing of the seepage channel and the uniformity of the seepage field. However, existing true triaxial seepage head installation technology has significant bottlenecks: traditional installation methods rely on manual adjustment, achieving alignment between the head and sample through visual observation and experience. This is not only inefficient but also cannot avoid alignment deviations caused by human operation. Such deviations can lead to seepage path offsets, uneven local stress on the sample, and consequently, distortion of seepage flow measurement and premature sample failure, severely affecting the accuracy and repeatability of test data.

[0004] Therefore, overcoming the limitations of traditional manual installation and achieving automated and precise installation of true triaxial seepage heads has become an urgent need to improve the reliability of true triaxial seepage tests. Based on this background, this invention aims to develop a convenient installation device that integrates precise alignment, stable clamping, and smooth movement. Through optimized mechanical structure design, it completely solves the alignment deviation problem during seepage head installation, while simplifying the installation process. This provides efficient and reliable technical support for true triaxial seepage tests, contributing to scientific research and engineering practice in fields such as deep geotechnical engineering and resource development.

[0005] Currently, the installation technology of seepage head in true triaxial seepage tests faces the following key bottlenecks, which seriously restrict the improvement of test quality and efficiency: First, manual alignment has low accuracy and a high risk of data distortion. Traditional installation relies entirely on manual adjustment of the pressure head position, judging alignment with the rock sample by visual inspection, which cannot achieve precise positioning. This method is prone to axial and radial alignment deviations, resulting in poor sealing of the seepage channel and uneven distribution of the seepage field. Consequently, the measured seepage flow rate deviates significantly from the true value, and may even cause localized stress concentration in the sample, leading to premature failure. This seriously affects the accuracy and repeatability of the test data.

[0006] Secondly, the installation process is cumbersome and the testing efficiency is low. True triaxial flow tests usually require multiple sample replacements or adjustments to the pressure head position. Traditional installation methods require repeated disassembly, adjustment, and fixing, which are cumbersome and time-consuming for each installation. Especially in high-throughput testing scenarios, manual installation has become a major factor restricting the test progress.

[0007] Third, there is a lack of integrated installation tools and insufficient adaptability. Most existing installation tools are general-purpose clamps that are not specifically designed for the structural characteristics and installation requirements of true triaxial seepage heads. They cannot be effectively adapted to true triaxial testing equipment and are prone to interference with other components of the test bench during installation, further reducing installation accuracy. Summary of the Invention

[0008] The purpose of this invention is to provide a device for convenient installation of a true triaxial seepage head, which solves the problems of low efficiency, poor docking accuracy, and easy damage to precision heads and rock samples in the existing traditional manual installation of seepage heads.

[0009] The first objective of this invention is to provide a device for conveniently installing a true triaxial seepage head, comprising: a base unit, a motion execution unit, and a clamping unit; The base unit includes a base for fixing to a true triaxial test bench and a frame fixed to the base; The motion execution unit includes: A vertical drive module, mounted on the base, is used to drive the clamping unit to move in the vertical direction. The vertical drive module includes an adjusting screw, a lifting adjustment plate, and a guide column. The adjusting screw is rotatably connected to the lifting adjustment plate, and the top end of the adjusting screw is threadedly connected to the bottom of the clamping unit. A horizontal drive module, connected to the clamping unit, is used to drive the clamping unit to move along a first horizontal direction. The horizontal drive module includes at least one horizontally arranged slide rail and a sliding connector. The horizontally arranged slide rail is mounted on the top of the base. The clamping unit is slidably connected to the horizontally arranged slide rail through the sliding connector, so that the clamping unit can move horizontally along the horizontally arranged slide rail. The clamping unit includes: A pressure head clamp is used to clamp and release a seepage pressure head. The pressure head clamp includes a fixed platform with a groove on the top for accommodating the seepage pressure head. The pressure head clamp also includes a clamp plate detachably connected to the top of the fixed platform. The clamp plate cooperates with the groove to press and fix the seepage pressure head placed in the groove from above.

[0010] The second objective of this invention is to provide an installation method using the aforementioned device for convenient installation of a true triaxial seepage head, comprising the following steps: S1 Clamping and Initialization: Clamp the seepage head into the head clamp, and reset all modules of the system to their initial positions; S2 Coarse Positioning: The central control unit controls the vertical drive module and the horizontal drive module to move the seepage head to a position close to the theoretical coordinates of the sample chamber; S3 Vision-Assisted Precision Positioning: Activate the vision sensor to identify the actual characteristics of the sample cavity interface, calculate the pose deviation, and perform pose compensation alignment by controlling the multi-dimensional fine-tuning platform. S4 Force Control Soft Docking: After the seepage pressure head approaches the preset distance, it switches to force control mode and slowly advances with a constant low contact force until the contact force fed back by the pressure sensing component reaches the preset value and the distribution meets the requirements. S5 clamp release and retraction: After confirming stable docking, control the pressure head clamp to release the seepage pressure head, and then control the motion execution unit to retract the installation system along the predetermined trajectory.

[0011] This invention, through integrated and precise mechanical structure design, solves the core defects of existing true triaxial seepage head installation technology, achieving multi-dimensional technological breakthroughs, with the following beneficial effects: (1) Overcoming the limitations of manual installation and achieving precise installation. By adjusting the height of the vertical drive module and guiding the horizontal movement of the horizontal drive module, the alignment accuracy between the seepage head and the rock sample is improved, which solves the alignment deviation problem of traditional manual installation, ensures that the seepage channel is tightly sealed and the seepage field is evenly distributed, improves the accuracy and repeatability of true triaxial seepage test data, and provides reliable data support for the study of rock seepage characteristics.

[0012] (2) Simplify the installation process and improve the efficiency of testing. This device integrates multiple functions such as clamping, moving and aligning. The installation process does not require complicated tools, and the time required for a single installation is significantly reduced compared to the traditional method. It also supports quick disassembly and reinstallation, making it particularly suitable for high-throughput testing scenarios. It effectively solves the problems of cumbersome and inefficient traditional installation processes.

[0013] (3) Stable and reliable clamping, avoiding damage to the sample and indenter. The combination design of the clamping plate and the grooved rubber pad achieves flexible clamping of the seepage indenter. The clamping force can be precisely controlled, which not only ensures that the seepage indenter does not loosen or shift during the test, but also avoids deformation of the seepage indenter or local damage to the sample caused by excessive clamping, thus achieving a balance between stable and non-destructive installation. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 The front view of the device for convenient installation of a true triaxial seepage head according to the present invention is shown; Figure 2 The diagram shows a top view of the device for convenient installation of a true triaxial seepage head according to the present invention. Figure 3 A side view of the device for convenient installation of a true triaxial seepage head according to the present invention is shown; Figure 4 The three views of the pressure head clamp of the present invention are shown; Figure 5 The diagram showing the connection between the pressure head clamp and the fixed platform in this invention is illustrated. Figure 6 A top view of the base in this invention is shown; Figure 7 The diagram shows cross-sectional views of the bottom and side slide rails in this invention; Figure 8 The workflow of the installation method of the present invention is shown.

[0016] Explanation of reference numerals in the attached diagram: 1-Frame; 2-Groove; 3-Fixing platform; 4-Bolt; 5-Base; 6-Slide rail; 7-Threaded hole; 8-Ball bearing. Detailed Implementation

[0017] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0018] To fully understand this invention, detailed steps and structures will be presented in the following description to illustrate the technical solution of this invention. Preferred embodiments of the invention are described in detail below; however, in addition to these detailed descriptions, the invention may have other embodiments.

[0019] Example 1: refer to Figures 1 to 7 This embodiment provides a device for convenient installation of a true triaxial seepage head. The device is installed on the base of a true triaxial test bench and mainly includes a base unit, a motion execution unit, and a clamping unit.

[0020] The base unit includes a base 5 and a frame 1. The base 5 is made of high-strength steel and has multiple threaded holes at its bottom. It is fixedly connected to the true triaxial test bench by bolts 4, providing a stable installation foundation for the entire device. The frame 1 is welded from square steel, and its height matches the height of the sample chamber of the true triaxial test bench. The bottom of the frame 1 is welded and fixed to the base 5, and the sides are designed to be open or grid-like, making it easy for operators to observe the installation process.

[0021] The motion execution unit includes a vertical drive module and a horizontal drive module. The vertical drive module is mounted above the base 5 and is used to drive the clamping unit to move vertically. Specifically, the vertical drive module includes an adjusting screw, a lifting adjustment plate, and a guide column. The adjusting screw is rotatably connected to the lifting adjustment plate, and its top end forms a threaded pair with the threaded hole 7 at the bottom of the fixed platform 3 in the clamping unit. By rotating the adjusting screw, the fixed platform 3 can be driven to move precisely up and down relative to the lifting adjustment plate, thereby achieving the vertical movement of the clamping unit. The adjustment accuracy can reach 0.1mm, enabling precise adjustment of the seepage head height to ensure it is on the same horizontal plane as the seepage channel of the rock sample.

[0022] The horizontal drive module is used to drive the clamping unit to move along a first horizontal direction, i.e., toward or away from the sample. The horizontal drive module includes at least one horizontally arranged horizontal slide rail and a sliding connector. The horizontal slide rail is mounted on the top of the base 5. The clamping unit is slidably connected to the horizontal slide rail via the sliding connector at its bottom, thereby enabling it to move horizontally along the slide rail.

[0023] The clamping unit is used to clamp and fix the seepage head. Its core component is the head clamp, which includes a fixing platform 3. The top of the fixing platform 3 has a groove 2 adapted to the shape of the seepage head. The inner wall of the groove 2 is lined with a non-slip, wear-resistant rubber pad, ensuring initial positioning of the seepage head after placement and preventing direct contact between the head and the groove 2, thus avoiding wear. The head clamp also includes a clamping plate detachably connected to the top of the fixing platform 3. This clamping plate cooperates with the groove 2 to press and fix the seepage head placed within the groove 2 from above.

[0024] In one specific embodiment, the horizontal drive module further includes two lateral slide rails 6 respectively disposed on opposite sides of the frame 1. The two sides of the clamping unit are slidably connected to the two lateral slide rails 6 via sliding connectors. These two lateral slide rails 6 do not provide active driving force, but are used to limit the deflection of the clamping unit during horizontal movement. The horizontally disposed horizontal slide rail 6 at the bottom, together with the two lateral slide rails 6, constitutes a three-sided slide rail guide structure. They work together to constrain the fixed platform 3 from below and from both sides, ensuring that it can only move smoothly and linearly along a single X-axis, improving the accuracy and stability of the movement alignment. The horizontally disposed slide rail 6 at the bottom uses a high-precision linear slide rail, ensuring that the fixed platform 3 drives the seepage head to move smoothly with a movement accuracy of up to 0.05 mm, achieving precise axial alignment between the seepage head and the rock sample.

[0025] In one specific embodiment, the sliding connector, i.e., the slider that mates with the horizontal slide rail, the left-side slide rail, and the right-side slide rail, has a precision ball bearing circulation channel inside. The ball bearings 8 embedded in each slider form a high-precision rolling friction pair with the corresponding slide rail surface. This reduces the sliding friction force experienced by the fixed stage 3 and the seepage head it carries to rolling friction force during the advancement along the X-axis, making operation not only easier but, more importantly, improving the smoothness of movement and displacement resolution. To eliminate gaps and ensure precise guidance without wobbling, the sliding connector is typically equipped with an adjustable pre-tightening device, which maintains optimal pre-tightening between the balls and the rails, effectively suppressing backlash and creep during movement, providing a reliable mechanical basis for aligning the seepage head with the sample interface. Combined with manual operation mode or precise control of the servo motor by the central control unit, this device can achieve smooth movement throughout the entire process, from coarse to fine, ensuring repeatability and long-term stability during docking.

[0026] In one specific embodiment, the shape of the groove 2 is adapted to the shape of the seepage head to achieve preliminary circumferential positioning. The inner wall of the groove 2 is lined with a non-slip, wear-resistant rubber pad, which increases friction to prevent the head from sliding and avoids direct metal-to-metal contact that could cause wear. The clamping plate is connected to the fixing platform 3 by bolts 4. The inner side of the clamping plate has an arc-shaped structure that conforms to the upper contour of the seepage head, and the inner side of this arc-shaped structure is also provided with a rubber pad 12. By tightening or loosening the bolts 4 on both sides, the clamping plate can reliably clamp or quickly release the seepage head, with controllable clamping force, effectively preventing the head from loosening or deforming.

[0027] In one specific embodiment, to improve the device's adaptability to different types of pressure heads, a modular quick-change connection structure is adopted between the clamping plate and the fixed platform 3, connected by positioning pins and quick-release bolts for easy and rapid replacement. And / or, the groove 2 is an independent module detachably embedded within the fixed platform 3. The device can be equipped with multiple clamping plates and groove 2 modules of different sizes and shapes, each adapted to different types of seepage pressure heads. During operation, the corresponding clamping plate and groove 2 module can be quickly replaced according to the currently used pressure head model, achieving multi-purpose functionality and improving the equipment's versatility and efficiency.

[0028] In one specific embodiment, as an alternative clamping solution, the clamping plate can be replaced with an adaptive gripper. Its driving method can be pneumatic, electric, or a manual screw centering mechanism. This adaptive gripper can adaptively clamp seepage heads of different diameters within a certain size range without requiring component replacement, further simplifying operation. It is particularly suitable for scenarios where head size changes are infrequent but ease of operation is paramount.

[0029] In one specific embodiment, to achieve higher-precision pose fine-tuning after coarse positioning, the motion execution unit further includes a multi-dimensional fine-tuning platform. This multi-dimensional fine-tuning platform is connected between the horizontal drive module and the clamping unit. The multi-dimensional fine-tuning platform provides at least two additional degrees of freedom for fine-tuning: first, yaw angle fine-tuning about the vertical axis to correct angular deviations of the indenter in the horizontal plane; and second, translational fine-tuning along a second horizontal direction (Y-axis) perpendicular to the first horizontal direction (X-axis) to correct lateral positional deviations of the indenter. This enables the device to achieve precise alignment of four key degrees of freedom out of the six.

[0030] In one specific embodiment, the multidimensional fine-tuning platform is a parallel micro-stage based on a piezoelectric ceramic actuator. It transmits motion and force through precise flexible hinges, providing fine-tuning degrees of freedom for yaw angle adjustment around the Z-axis and fine-tuning for translation along the second horizontal direction (Y-axis), with a displacement resolution down to the sub-micrometer level, to compensate for accumulated errors in previous motion and machining assembly.

[0031] In one specific embodiment, to achieve intelligent monitoring of the installation process, the clamping unit also includes an integrated sensing module. This module includes at least: a position sensor for monitoring the spatial position of the indenter clamp in the X, Y, and Z directions, which can be a grating ruler; a pressure sensing component for monitoring the magnitude and distribution of pressure at the contact surface between the indenter clamp and the seepage indenter, which can be a thin-film pressure sensor array integrated within the clamping plate or groove 2. This array consists of multiple miniature thin-film pressure sensors capable of measuring the pressure values ​​at various points on the contact surface when the seepage indenter end face contacts the rock sample in real time, thereby generating a contact pressure cloud map; and a vision sensor for acquiring images of the area where the indenter front end meets the sample, which can be a small industrial camera. The integrated sensing module provides real-time feedback for automatic control. The small industrial camera is fixed to the frame via a mounting bracket, with its field of view aligned with the sample cavity interface area to capture images of the interface.

[0032] In one specific embodiment, the integrated sensing module further includes a miniature ultrasonic flaw detection sensor, the probe of which is integrated into one of the arc surfaces of the groove 2 in the clamping plate or fixing platform 3. After the seepage pressure head is clamped and before docking, the miniature ultrasonic flaw detection sensor can be activated to perform non-destructive testing on the area where the seepage pressure head will come into contact with the sample, and to identify potential defects.

[0033] In one specific embodiment, the device further includes a central control unit, which can be a PLC or an industrial computer. The central control unit is communicatively connected to the motion actuator and the integrated sensing module via a cable. The central control unit receives feedback signals from position, pressure, and vision sensors, processes them according to a preset algorithm, and then automatically controls the coordinated actions of the vertical drive module, the horizontal drive module, and the multi-dimensional fine-tuning platform. Ultimately, this achieves automatic positioning and force-controlled smooth docking of the seepage head, reducing operational difficulty and reliance on personnel experience.

[0034] Example 2: refer to Figure 8 This embodiment provides a method for installing a seepage head using the device described in Embodiment 1 for convenient installation of a true triaxial seepage head. This method is particularly suitable for true triaxial seepage test scenarios with high requirements for installation accuracy, repeatability, and automation. The core steps of this method include: S1 Clamping and Initialization: The operator places the target seepage head into the groove 2 of the fixed platform 3 and clamps it using clamping plates or adaptive jaws. Subsequently, a start command is sent to the central control unit via the control panel or host computer software, and the system controls each module of the motion execution unit to reset to the preset initial safe position.

[0035] S2 Coarse Positioning: The central control unit generates a motion path based on the theoretical three-dimensional coordinates of the sample chamber interface, either pre-inputted or retrieved from the database. First, it controls the motor of the vertical drive module to rotate the adjusting screw, adjusting the seepage head to the theoretical height. Next, it controls the horizontal drive module to move the entire clamping unit along the horizontal slide rail 6, sending the seepage head to the theoretical X-coordinate position close to the sample chamber inlet. This process is rapid movement, achieving preliminary, large-range positioning.

[0036] S3 Vision-Assisted Precision Positioning: The vision sensor integrated into the frame is activated to acquire images of the current seepage head tip and the sample chamber interface area. The central control unit uses machine vision algorithms to identify the actual edges, center, and other features of the sample chamber interface, and compares them with the features of the seepage head to calculate the positional deviations in the X and Y directions and the yaw angle deviation around the Z axis. Subsequently, the central control unit controls the multi-dimensional fine-tuning platform to precisely compensate for the calculated deviations through its Y-axis translation fine-tuning mechanism and yaw angle fine-tuning mechanism, respectively, so that the pose of the seepage head is precisely aligned with the sample interface.

[0037] S4 Force-Controlled Compliant Docking: After visual precision positioning, the central control unit controls the horizontal drive module to slowly approach the percolation head towards the sample interface at a low speed. When the pressure sensing component integrated on the clamping unit detects that the contact force has reached a low preset threshold, the system automatically switches to force control mode. In this mode, the system continues to advance with a constant, low desired contact force, while simultaneously monitoring the contact surface pressure distribution fed back by the pressure sensing component in real time.

[0038] S5 Clamp Release and Retraction: When the contact force fed back by the pressure sensing component stabilizes at the preset final docking force value and the pressure distribution uniformity meets the requirements, and remains stable for a period of time, the central control unit determines that the docking is successful and stable. Subsequently, it controls the drive mechanism of the clamping unit to release the clamping plate or adaptive gripper, releasing the seepage pressure head. Finally, it controls the motion execution unit to smoothly retract the fixed platform 3 and clamping plate and other components to the initial position or the set standby position according to the predetermined safety trajectory, completing the entire automatic installation process.

[0039] In one specific embodiment, during the force-controlled compliant docking process in step S4, the central control unit analyzes the pressure distribution cloud map fed back by the pressure sensing component in real time and calculates the pressure uniformity across the entire contact surface. If the pressure distribution non-uniformity is detected to exceed the set safety threshold, it indicates that the seepage pressure head may be in tilted contact with the sample interface, posing a risk of stress concentration or leakage. At this time, the central control unit can attempt to uniformize the pressure distribution by controlling the multi-dimensional fine-tuning platform to perform minor pitch / roll leveling around the X or Y axis, or by performing dynamic lateral fine-tuning. If the system cannot automatically level or the pressure non-uniformity continues to exceed the limit, the central control unit will immediately issue an audible and visual alarm and suspend the docking process, prompting the operator to intervene and check, thereby effectively preventing equipment or sample damage due to misoperation.

[0040] The preferred embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, nor is it limited to the apparatus and method for conveniently installing a true triaxial seepage head. Devices and structures not described in detail herein should be understood as being implemented in a manner common to the art. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention, or modify them into equivalent embodiments, without departing from the scope of the present invention. This does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the present invention are still within the scope of protection of the present invention.

Claims

1. A device for facilitating installation of a true triaxial seepage head, comprising: It includes a base unit, a motion execution unit, and a clamping unit; The base unit includes a base for fixing to a true triaxial test bench and a frame fixed to the base; The motion execution unit includes: A vertical drive module, mounted on the base, is used to drive the clamping unit to move in the vertical direction. The vertical drive module includes an adjusting screw, a lifting adjustment plate, and a guide column. The adjusting screw is rotatably connected to the lifting adjustment plate, and the top end of the adjusting screw is threadedly connected to the bottom of the clamping unit. A horizontal drive module, connected to the clamping unit, is used to drive the clamping unit to move along a first horizontal direction. The horizontal drive module includes at least one horizontally arranged slide rail and a sliding connector. The horizontally arranged slide rail is mounted on the top of the base. The clamping unit is slidably connected to the horizontally arranged slide rail through the sliding connector, so that the clamping unit can move horizontally along the horizontally arranged slide rail. The clamping unit includes: A pressure head clamp is used to clamp and release a seepage pressure head. The pressure head clamp includes a fixed platform with a groove on the top for accommodating the seepage pressure head. The pressure head clamp also includes a clamp plate detachably connected to the top of the fixed platform. The clamp plate cooperates with the groove to press and fix the seepage pressure head placed in the groove from above.

2. The apparatus for easy installation of true tri-axial seepage pressure head as claimed in claim 1 wherein: The horizontal drive module also includes two lateral slide rails respectively set on opposite sides of the frame. The two sides of the clamping unit are slidably connected to the two lateral slide rails through sliding connectors. The two lateral slide rails are used to limit the clamping unit from deflection during horizontal movement. The slide rail set horizontally at the bottom and the two lateral slide rails form a three-sided slide rail guide structure, which together constrains the fixed table to move only in a single horizontal direction.

3. The device for convenient installation of a true triaxial seepage head according to claim 1, characterized in that: The shape of the groove is adapted to the shape of the seepage head, and a rubber pad is attached to the inner wall of the groove; the clamping plate is connected to the fixing platform by bolts, and the inner side of the clamping plate is provided with an arc-shaped structure that fits the contour of the seepage head, and a rubber pad is provided on the inner side of the arc-shaped structure.

4. The device for convenient installation of a true triaxial seepage head according to claim 1, characterized in that: The clamping plate and the fixed platform are connected by a modular quick-change structure; and / or, the groove is an independent module that can be detachably embedded in the fixed platform. The device is equipped with multiple clamping plate and / or groove modules whose shapes are adapted to different models of seepage pressure heads.

5. The device for convenient installation of a true triaxial seepage head according to claim 1, characterized in that: The clamping plate is an adaptive gripper, driven by pneumatic, electric or manual screw alignment, and can adaptively clamp seepage pressure heads within a certain size range.

6. The device for convenient installation of a true triaxial seepage head according to claim 1, characterized in that: The motion execution unit also includes a multi-dimensional fine-tuning platform, which is connected between the drive end of the horizontal drive module and the clamping unit. The multi-dimensional fine-tuning platform provides at least the yaw angle fine-tuning for rotation about the vertical axis and the translational fine-tuning degree of freedom for a second horizontal direction perpendicular to the first horizontal direction.

7. The device for convenient installation of a true triaxial seepage head according to claim 1, characterized in that: The clamping unit also includes an integrated sensing module, which includes at least a position sensor for monitoring the spatial position of the pressure head clamp, a pressure sensing component for monitoring the pressure at the contact surface between the pressure head clamp and the seepage pressure head, and a vision sensor for acquiring images of the docking area.

8. The device for convenient installation of a true triaxial seepage head according to claim 1, characterized in that: The device also includes a central control unit, which is communicatively connected to the motion execution unit and the integrated sensing module. It receives feedback signals from the integrated sensing module and controls the actions of each module in the motion execution unit to achieve automatic positioning and force control docking of the seepage head.

9. An installation method, employing the device for convenient installation of a true triaxial seepage head as described in claim 8, characterized in that, Includes the following steps: S1 Clamping and Initialization: Clamp the seepage head into the head clamp, and reset all modules of the system to their initial positions; S2 Coarse Positioning: The central control unit controls the vertical drive module and the horizontal drive module to move the seepage head to a position close to the theoretical coordinates of the sample chamber; S3 Vision-Assisted Precision Positioning: Activate the vision sensor to identify the actual characteristics of the sample cavity interface, calculate the pose deviation, and perform pose compensation alignment by controlling the multi-dimensional fine-tuning platform. S4 Force Control Soft Docking: After the seepage pressure head approaches the preset distance, it switches to force control mode and slowly advances with a constant low contact force until the contact force fed back by the pressure sensing component reaches the preset value and the distribution meets the requirements. S5 clamp release and retraction: After confirming stable docking, control the pressure head clamp to release the seepage pressure head, and then control the motion execution unit to retract the installation system along the predetermined trajectory.

10. The device for convenient installation of a true triaxial seepage head according to claim 1, characterized in that: In step S4, the central control unit analyzes the pressure distribution cloud map fed back by the pressure sensing component in real time. If the pressure distribution unevenness is detected to exceed the threshold, the multi-dimensional fine-tuning platform is controlled to dynamically level the pressure, or an alarm is issued and the process is paused.

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