A device and method for measuring dynamic contact angle of geotechnical materials

Abstract

A device for measuring the dynamic contact angle of geotechnical materials includes a sampling device, an operating platform, a mobile platform, a lifting platform, a rotating platform, a droplet control system, and an external terminal. The sampling device includes a sample press for preparing a reshaped sample and a small ring knife for preparing an original sample; the operating platform includes a left and right translation system and two precision fixtures; the mobile platform is installed on the operating platform, including a front and back translation system; the lifting platform is on the mobile platform, including a lifting system; the rotating platform is installed on the lifting platform, including a rotation system that can quickly and accurately control the geotechnical sample at different inclination angles, consisting of a degree, minute, and second rotation axis, a degree, minute, and second rotating disk, and a projection screen; the droplet control system uses a motor spiral piston for precise control; the external terminal is a large aperture high-definition digital camera and a computer. The present invention also provides a corresponding measurement method, which can directly measure the dynamic contact angle of the geotechnical sample, with high accuracy, simple operation, and easy to promote and use.

Description

Technical Field

[0001] The invention belongs to the technical field of geotechnical experimental instruments, relates to the testing of geotechnical materials, and particularly relates to a device and method for measuring the dynamic contact angle of geotechnical materials. Background Art

[0002] Unsaturated granular materials, such as geotechnical materials, have very complex mechanical properties due to the presence of suction (capillary force). There are many factors that affect suction, and the existence of the water-air interface is the fundamental reason. At present, the contact angle is used to accurately define the interface characteristics between any two phases of matter. The contact angle includes static contact angle and dynamic contact angle. Due to the complex three-phase characteristics of geotechnical materials, the accurate test of the contact angle has always been a technical problem, especially the test of the dynamic contact angle. There are two main technical means for testing the dynamic contact angle. The first method is to increase or decrease the small water droplets on the plane, and the second option is to tilt the test frame as a whole. These two methods have better test effects on general materials. The second method is more widely used because it can clearly observe the shape and movement trajectory of the droplets, but the test effect on geotechnical materials is poor. The main reason is that geotechnical materials are granular porous media materials with significant seepage effects. The overall tilt test frame is slow and it is difficult to record the shape and movement trajectory of the droplets, resulting in poor test results. Summary of the invention

[0003] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a device and method for measuring the dynamic contact angle of geotechnical materials, which solves the problem that traditional testing methods are difficult to accurately obtain the dynamic contact angle of geotechnical materials.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A device for measuring the dynamic contact angle of geotechnical materials, comprising an operating platform 1, a rotating platform 4 and an external terminal, wherein the rotating platform 4 is located above the operating platform 1, can be raised and lowered, and can be translated forward, backward, left and right along the operating platform 1, a vertical rod 12 is arranged on the operating platform 1, and a precision fixture for fixing a droplet control system 5 is connected to the vertical rod 12, the droplet control system 5 comprises a liquid-filling bottle with a dropper at the bottom, a threaded piston is arranged in the liquid-filling bottle, and the threaded piston is directly connected to a motor M-e14, the rotating platform 4 is provided with degree, minute and second rotating disks, each disk is connected with a rotating shaft 6 and a driven shaft 7, a sampling device is arranged on the second rotating disk, and the sampling device It includes a base, on which a small ring cutter is arranged, a rock and soil sample 16 is located inside the small ring cutter, a guard ring is arranged on the outside of the small ring cutter, a pressure head acts on the top of the guard ring, and the guard ring, the base and the pressure head are assembled to tightly fit the small ring cutter, so that the remaining volume is a fixed value, even if the sample volume is a fixed value after the pressing is completed, the dropper is vertically located above the center of the rock and soil sample 16; a vertical projection board 10 is arranged on the rotating platform 4 at a position opposite to the motor M-a9, and the external terminal includes a large aperture high-definition digital camera 15 and a computer 8, wherein the lens of the large aperture high-definition digital camera 15 is aimed at the front of the sample 16 and the dropper, and is projected onto the projection board 10.

[0006] A mobile platform 2 is arranged on the operating platform 1, a lifting platform 3 is arranged on the mobile platform 2, and a rotating platform 4 is arranged on the lifting platform 3, wherein the bottom of the operating platform 1 includes a left and right translation connecting rod device connected to the motor Md, the mobile platform 2 is connected to the left and right translation connecting rod device, the mobile platform 2 includes a front and rear translation connecting rod device connected to the motor Mc, the lifting platform 3 is connected to the front and rear translation connecting rod device, and the lifting platform 3 includes a lifting connecting rod device 11 connected to the motor Mb.

[0007] The operating platform 1 has four leveling nuts 17 at the bottom, two vertical strip levels 18a, 18b above the base, and two left and right slide grooves of 22.5mm×5mm on the top; the mobile platform 2 has four circular holes at the bottom, and the positions of the circular holes correspond to the positions of the left and right translation connecting rods of the operating platform 1. The hole diameter and hole depth are both 5mm, and two front and rear slide grooves of 22.5mm×5mm are left on the top; the lifting platform 3 has four circular holes at the bottom, and the positions of the circular holes correspond to the positions of the front and rear translation connecting rods of the mobile platform 2. The hole diameter and hole depth are both 5mm, and four circular holes with a diameter of 5mm are left on the top, corresponding to the positions of the lifting connecting rods 11.

[0008] The precision fixture includes a precision fixture 13a located at a high position and a precision fixture 2 13b located at a low position, wherein the precision fixture 13a clamps the motor M-e14, and the precision fixture 2 13b clamps the liquid bottle.

[0009] The rotating shaft 6 is connected to the motor M-a9, and the contact between the motor M-a9 and the rotating shaft 6 is precisely controlled by the computer 8, so as to accurately and quickly control the rotation angle of the rotating platform 4.

[0010] The computer 8 is connected to the large aperture high definition digital camera 15 and each motor, controls the operation time of each motor, and receives and analyzes the image data of the large aperture high definition digital camera 15 .

[0011] The guard ring, base and pressure head constitute a sample press for preparing reshaped samples; the small ring knife is used to prepare original samples, and the outer side of its upper edge has a cutting structure with the cutting edge facing upward, which is convenient for cutting original samples. The rock and soil sample 16 is placed downward with the cutting edge, and fits tightly with the protruding groove on the second rotating disk to ensure that the position does not change during rotation.

[0012] The rotating shaft 6 is composed of a degree shaft 19a, a minute shaft 19b and a second shaft 19c, each shaft is connected to the motor M-a9, the side close to the motor M-a9, each rotating disk is connected with a shaft, and the distal side is connected with a driven shaft 7, and the three shafts are all sleeve-shaped, the degree shaft 19a is on the outermost side, one end of which is connected to the degree rotating disk; the minute shaft 19b is on the inner side of the degree shaft 19a and the outer side of the second shaft 19c, one end of which is connected to the minute rotating disk; the second shaft 19c is on the innermost side, one end of which is connected to the second rotating disk. When the degree shaft 19a rotates one circle, the rotating platform 4 rotates 360°; when the minute shaft 19b rotates one circle, the rotating platform 4 rotates 360′; when the second shaft 19c rotates one circle, the rotating platform 4 rotates 36 0″, the degree axis 19a is sleeved on the outside of the sub-axis 19b, and the sub-axis 19b is sleeved on the outside of the second axis 19c. There are four sheet-like buckles 21 on the rotating rod 20 of the motor M-a9, and each axis has a slot matching each buckle 21. When the degree axis 19a needs to be rotated, the buckle 21 directly extends to the outermost side; when the sub-axis 19b needs to be rotated, the buckle 21 extends to the inner side of the degree axis 19a; when the second axis 19c needs to be rotated, the buckle 21 extends to the innermost side. In this way, it can be ensured that the rotation of the degree axis 19a will drive the sub-axis 19b, but the rotation of the sub-axis 19b will not drive the degree axis 19a, the rotation of the sub-axis 19b will drive the second axis 19c, but the rotation of the second axis 19c will not drive the sub-axis 19b.

[0013] The present invention also provides a measurement method using the rock material dynamic contact angle measurement device, comprising the following steps:

[0014] Step 1: Level the device and apply lubricating oil to each translation and rotation point to ensure uniform sliding and rotation during the test;

[0015] Step 2: preparing a rock and soil sample 16;

[0016] Step 3: Fill the liquid required for the test into the liquid bottle, install it on the precision fixture, adjust the threaded piston, and exhaust the gas in the liquid bottle;

[0017] Step 4: Place the rock and soil sample 16 on the second rotating disk of the rotating platform 4, control the motors Mb, Mc, and Md, and adjust the position of the rock and soil sample 16 and the dropper so that the large aperture high-definition digital camera 15 can focus clearly;

[0018] Step 5: Turn on the large aperture high-definition digital camera 15 to start recording, control the motor M-e 14, push the threaded piston, and drip a drop of the designed volume onto the rock and soil sample 16;

[0019] Step 6: Control the motor M-a9 to quickly rotate the degrees, minutes, and seconds to record the shape and trajectory of the droplet. When the droplet becomes unstable, stop recording;

[0020] Step 7: Control motors Mc and Md to repeat steps 5 and 6 at other locations of the sample to obtain control results and eliminate the influence of accidental factors on the test results.

[0021] Step 8: Data analysis: compile an application for measuring the dynamic contact angle of geotechnical materials based on the image recognition toolbox, and use the image data captured in steps 5 and 6 to obtain the dynamic contact angle of geotechnical materials.

[0022] Among them, the method for preparing the rock and soil sample 16 is: put a small ring cutter into the base, put on a protective ring, put the dry soil sample and water of the required mass into the ring cutter, press the pressure head, put the sample press into the hydraulic jack reaction frame, use the hydraulic jack to pressurize the pressure head by 5MPa, and the duration is 3min to obtain the reshaped sample required for the test. When preparing the original sample, directly use the small ring cutter to take the sample.

[0023] Compared with the prior art, the present invention is directly used to test the dynamic contact angle of rock and soil materials, is fast and accurate, and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a diagram of a device for measuring the dynamic contact angle of rock and soil materials according to the present invention.

[0025] Figure 2 It is a schematic diagram of the installation effect of the experimental device of the present invention.

[0026] Figure 3 It is a cross-sectional view of the small ring knife of the sampling device of the present invention.

[0027] Figure 4 for Figure 3 Middle AA section view.

[0028] Figure 5 Schematic diagram of the upper pressure head of the sample press.

[0029] Figure 6 for Figure 5 Middle BB section view.

[0030] Figure 7 This is a cross-sectional view of the guard ring of the sample press.

[0031] Figure 8 for Figure 7 Middle CC section view.

[0032] Fig. 9 This is a cross-sectional view of the base of the sample press.

[0033] Fig.10 for Fig. 9 Middle DD section view.

[0034] Fig.11 This is the layout diagram of the rotating disks on the rotating platform.

[0035] Fig.12 for Fig.11 EE section view.

[0036] Fig.13 This is the layout diagram of the rotating axes of the rotating platform.

[0037] Fig.14 for Fig.13 Middle FF cross-sectional view.

[0038] Fig.15 for Fig.14 Sectional view 1-1.

[0039] Fig.16 for Fig.14 Sectional view 2-2.

[0040] Fig.17 It is the connection diagram between the rotating shaft and the motor Ma.

[0041] Fig.18 This is the elevation view of the operating platform.

[0042] Fig.19 for Fig.18 Middle GG section view.

[0043] Fig. 20 for Fig.18 Middle HH section view.

[0044] Fig.21 for Fig.18 Middle II sectional view.

[0045] Fig. 22 Schematic diagram of the mobile platform.

[0046] Fig.23 for Fig. 22 Middle JJ section view.

[0047] Fig.24This is a schematic diagram of the lifting platform.

[0048] Fig.25 for Fig.24 Middle KK section view.

[0049] Fig.26 Schematic diagram of the droplet control system.

[0050] For easy reference, the relevant recommended dimensions (unit: 1mm) are marked in the attached drawings. DETAILED DESCRIPTION

[0051] The embodiments of the present invention are described in detail below with reference to the accompanying drawings and examples.

[0052] like Figure 1 , Figure 2 As shown, the present invention is an experimental device for measuring the dynamic contact angle of geotechnical materials, which mainly includes an operating platform 1, a mobile platform 2, a lifting platform 3, a rotating platform 4, a droplet control system 5, a sampling device and an external terminal. The various parts cooperate with each other to measure the dynamic contact angle of geotechnical materials, wherein:

[0053] refer to Figure 3 , Figure 4 The volume of the sampling ring knife is a fixed value of 8cm 3 , just weigh the mass, and according to the basic physical parameters of the rock and soil sample, its porosity and water content can be obtained. The outer side of the upper edge of the small ring knife has a cutting structure with the cutting edge facing upward, which is convenient for cutting the original sample.

[0054] refer to Figure 5 , Figure 6 , Figure 7 , Figure 8 , Fig. 9 , Fig.10 After the pressure head, guard ring and base of the sampling device are assembled, a sample press is formed to prepare the reshaped sample; the sample press fits the small ring knife tightly to ensure that the sample volume is a fixed value of 8cm after the pressing is completed. 3 .

[0055] refer to Fig.11 , Fig.12 The rotating platform 4 is composed of degree, minute and second rotating disks. To better ensure the smooth rotation of each disk, the distance between each disk is 5mm. The cutter is placed downward, just fitting tightly with the protruding slot on the second rotating disk. This ensures that the position of the sample does not change when it rotates.

[0056] refer to Fig.13 , Fig.14 , Fig.15 , Fig.16 , Fig.17The rotating shaft 6 is composed of a degree shaft 19a, a minute shaft 19b, and a second shaft 19c. The three shafts are all sleeve-shaped. To ensure that each shaft only drives the corresponding rotating disk, each shaft is connected to the motor M-a9. Each rotating disk is connected with a corresponding shaft on the side close to the motor M-a9, and is connected with a driven shaft 7 on the far side. In this embodiment, the degree shaft 19a has a diameter of 6mm, and is connected to the degree rotating disk at the outermost side; the minute shaft 19b has a diameter of 4mm, and is connected to the minute rotating disk at the inner side of the degree shaft 19a and the outer side of the second shaft 19c; the second shaft 19c has a diameter of 2mm, and is connected to the second rotating disk at the innermost side. When the degree axis 19a rotates one circle, the rotating platform rotates 360°; when the minute axis 19b rotates one circle, the rotating platform rotates 360′; when the second axis 19c rotates one circle, the rotating platform rotates 360″. The degree axis 19a is sleeved on the outside of the minute axis, and the minute axis 19b is sleeved on the outside of the second axis 19c. There are four sheet-like buckles 21 on the rotating rod 20 of the motor M-a9, and each axis has a slot matching each buckle 21. When the degree axis 19a needs to be rotated, the buckle 21 directly extends to the outermost side; when the minute axis needs to be rotated, the buckle 21 directly extends to the outermost side. When the second axis 19c needs to be rotated, the buckle 21 extends to the inner side of the degree axis 19a; when the second axis 19c needs to be rotated, the buckle 21 extends to the innermost side. In this way, it can be ensured that the rotation of the degree axis 19a will drive the sub-axis 19b, but the rotation of the sub-axis 19b will not drive the degree axis 19a, and the rotation of the sub-axis 19b will drive the second axis 19c, but the rotation of the second axis 19c will not drive the sub-axis 19b. The motor M-a9 is directly opposite to the projection board 10 to ensure that the data collected by the high-definition digital camera 15 is not affected by the external environment.

[0057] refer to Fig.18 , Fig.19 , Fig. 20 , Fig.21 , there are four leveling nuts 17 at the bottom of the operating platform 1 to ensure the absolute level of the test platform and the accuracy of the sample inclination during the test. The bottom of the operating platform 1 contains a complete set of left and right translation devices. The translation device includes a motor Md and a translation connecting rod system. The horizontal connecting rod is directly connected to the motor Md, and the computer 8 controls the motor Md to push the horizontal connecting rod. The vertical connecting rod extending 15mm from the operating platform is directly fixed to the horizontal connecting rod to move left and right. In order to ensure smooth sliding of the connecting rod, a 22.5mm×5mm slide groove is left on the top of the operating platform 1. The computer 8 can control the left and right movement position of the connecting rod by precisely controlling the running time of the motor Md. In order to better fix the droplet control system, two precision clamps 13a, 13b are fixed on the vertical round rod 12.

[0058] refer to Fig. 22 , Fig.23There are four round holes at the bottom of the mobile platform 2. The positions of the round holes correspond to the positions of the vertical connecting rods of the operating platform 1. The hole diameter and hole depth are both 5mm, ensuring that the mobile platform is fixedly connected to the left and right translation connecting rods. The mobile platform includes a complete set of front and rear translation devices. The translation device includes a motor Mc and a translation connecting rod system. The horizontal connecting rod is directly connected to the motor Mc, and the computer 8 controls the motor Mc to push the horizontal connecting rod. The vertical connecting rod extending 15mm from the operating platform is directly fixed to the horizontal connecting rod to move forward and backward. In order to ensure smooth sliding of the connecting rod, a 22.5mm×5mm slide groove is left on the top of the mobile platform. The computer 8 can control the forward and backward movement position of the connecting rod by precisely controlling the running time of the motor Mc.

[0059] refer to Fig.24 , Fig.25 There are four round holes at the bottom of the lifting platform 3. The positions of the round holes correspond to the positions of the vertical connecting rods of the mobile platform. The hole diameter and hole depth are both 5mm, ensuring that the lifting platform is fixedly connected to the front and rear translation connecting rods. The lifting platform includes a complete set of lifting devices. The lifting device includes a motor Mb and a lifting connecting rod 9 system. The lifting connecting rod 9 is directly connected to the motor Mb. The computer 8 precisely controls the running time of the motor Mc and pushes the lifting connecting rod 9 up and down. In order to ensure smooth lifting of the connecting rod, four round holes with a hole diameter of 5mm are left on the top of the lifting platform. The lifting connecting rod is directly hinged to the rotating platform on all sides.

[0060] refer to Fig.26 The interface between the liquid bottle and the dropper is fixed by the lower clamp 13b, and the motor M-e14 is fixed by the upper clamp 13a. The threaded piston in the drop control system 5 is directly connected to the motor M-e14, and the threaded piston rotates counterclockwise to descend and clockwise to ascend. After the liquid bottle is filled with the test solution, the computer 8 accurately controls the running time of the motor M-e14 and the pushing distance of the threaded piston to determine the volume of the titrated liquid.

[0061] The operating platform 1, mobile platform 2, lifting platform 3, and rotating platform 4 are all made of 10F steel with a thickness of 2mm; the sampling device, small ring knife, translation connecting rod and lifting connecting rod are all made of 40# steel; the liquid bottle and threaded piston rod are made of high-transmittance inorganic glass material; the projection board 10 is coated with a highly diffuse reflective gray-white coating.

[0062] The specific steps of the testing method of the present invention are as follows:

[0063] Step 1: Instrument assembly. Figure 11-25Relevant recommended dimensions are given, and processing is carried out according to the drawings of each part. After the parts are processed, first lubricate each part of the experimental instrument to reduce the friction resistance of each part; then install the operating platform 1, level the operating platform 1, reset the translation connecting rod, align it with the extended end of the operating platform 1, and install the mobile platform 2. Reset the translation connecting rod of the mobile platform, align it with the extended end of the mobile platform, and install the lifting platform 3. Figure 11-16 , install the rotating platform 4, ensure the smoothness of each rotating axis. Hinged the rotating platform 4 on all sides to the extended end of the lifting platform. Set up a high-definition digital camera 15, facing the projection board 10.

[0064] Step 2: Attachment Fig.25 , connect the spiral piston to the motor M-e14, and the computer 8 can precisely control the rotation direction and running time of the motor M-e14. The bottom area of ​​the liquid bottle is a fixed value, and the volume of the test solution dripped out can be accurately calculated by the pushing distance of the spiral piston. After the liquid bottle is filled with the test solution, it is necessary to control the motor M-e14 to discharge the small bubbles in the liquid bottle to ensure the accuracy of the titrated test solution volume.

[0065] Step 3: Place the prepared small ring knife sample with the cut structure facing downward, and the small ring knife is closely fitted in the card slot of the second rotating disk. Further control the computer 8 to focus the high-definition digital camera 15 on the sample and the dropper position.

[0066] Step 4: When the test starts and the motor M-e14 starts running, the high-definition digital camera 15 starts to take pictures and collect data at a rate of once every 0.1s, and transmits it to the computer 8 in time.

[0067] Step 4: Data analysis: Based on the image recognition toolbox, an application program specifically used for contact angle measurement of geotechnical materials is compiled. The data obtained in step 4 and shot by the high-definition digital camera 15 are transmitted to the computer terminal 8 through signals for processing, thereby obtaining the dynamic contact angle measurement value.

[0068] Step 5: Disassemble and clean the instrument. After the experiment is completed, the experimental instrument can be disassembled and installed in a special device to prevent the experimental instrument from being damaged, which would affect the experimental accuracy.

[0069] In step 4, a data processing program is used to reduce the tediousness of manual calculation of contact angles, and is compiled based on an image recognition toolbox to perform contact angle analysis.

[0070] Data processing program: The data processing program is compiled based on the MATLAB image recognition toolbox, which mainly includes four parts: the first part, the interface part, is used to import image data; the second part, the format conversion, is used to convert the image data type into matrix data, and further convert it into grayscale image and binary image; the third part, image edge detection, is used to obtain the contact line profile; the fourth part, calculates the contact angle.

Claims

1. A device for measuring dynamic contact angle of geotechnical materials, characterized in that: The invention comprises an operating platform (1), a rotating platform (4) and an external terminal, wherein the rotating platform (4) is located above the operating platform (1) and can be raised and lowered and can be translated along the operating platform (1) in the front, back, left and right directions. A vertical rod (12) is arranged on the operating platform (1), and a precision fixture for fixing a drop control system (5) is connected to the vertical rod (12). The drop control system (5) comprises a liquid-filling bottle with a dropper at the bottom, and a threaded piston is arranged in the liquid-filling bottle, and the threaded piston is directly connected to a motor Me (14). The rotating platform (4) is provided with degree, minute and second rotating disks, and each disk is connected with a rotating shaft (6) and a driven shaft (7). A sampling device is arranged on the second rotating disk, and the sampling device The device comprises a base, a small ring knife is arranged on the base, a rock and soil sample (16) is located in the small ring knife, a protective ring is hooped on the outside of the small ring knife, a pressure head acts on the top of the protective ring, and the protective ring, the base and the pressure head are assembled to fit the small ring knife tightly, so that the volume of the sample is a constant value after the pressing is completed, and the dropper is vertically located above the center of the rock and soil sample (16); a vertical projection board (10) is arranged on the rotating platform (4) at a position facing the motor Ma (9), and the external terminal comprises a large aperture high-definition digital camera (15) and a computer (8), wherein the lens of the large aperture high-definition digital camera (15) is aimed at the front of the sample (16) and the dropper, and is projected onto the projection board (10).

2. The device for measuring the dynamic contact angle of geotechnical materials according to claim 1, characterized in that: The operating platform (1) is provided with a moving platform (2), the moving platform (2) is provided with a lifting platform (3), and the rotating platform (4) is provided on the lifting platform (3), wherein the bottom of the operating platform (1) comprises a left and right translation connecting rod device connected to a motor Md, the moving platform (2) is connected to the left and right translation connecting rod device, the moving platform (2) comprises a front and rear translation connecting rod device connected to a motor Mc, the lifting platform (3) is connected to the front and rear translation connecting rod device, and the lifting platform (3) comprises a lifting connecting rod device (11) connected to a motor Mb.

3. The device for measuring the dynamic contact angle of geotechnical materials according to claim 2, characterized in that: The operating platform (1) has four leveling nuts (17) at the bottom, two vertical bar levels (18a, 18b) above the base, and two left and right slide grooves of 22.5mm×5mm are left on the top; the movable platform (2) has four circular holes at the bottom, the positions of the circular holes correspond to the positions of the left and right translation connecting rods of the operating platform (1), the hole diameter and hole depth are both 5mm, and two front and rear slide grooves of 22.5mm×5mm are left on the top; the lifting platform (3) has four circular holes at the bottom, the positions of the circular holes correspond to the positions of the front and rear translation connecting rods of the movable platform (2), the hole diameter and hole depth are both 5mm, and four circular holes with a hole diameter of 5mm are left on the top, corresponding to the positions of the lifting connecting rods.

4. The device for measuring the dynamic contact angle of geotechnical materials according to claim 1, characterized in that: The precision fixture comprises a precision fixture 1 (13a) located at a high position and a precision fixture 2 (13b) located at a low position, wherein the precision fixture 1 (13a) clamps the motor Me (14), and the precision fixture 2 (13b) clamps the liquid bottle.

5. The device for measuring the dynamic contact angle of geotechnical materials according to claim 1, characterized in that: The rotating shaft (6) is connected to the motor Ma (9), and the contact between the motor Ma (9) and the rotating shaft (6) is precisely controlled by a computer (8), so as to accurately and quickly control the rotation angle of the rotating platform (4).

6. The device for measuring the dynamic contact angle of geotechnical materials according to claim 5, characterized in that: The computer (8) is connected to the large aperture high-definition digital camera (15) and each motor, controls the operation time of each motor, and receives and analyzes image data of the large aperture high-definition digital camera (15).

7. The device for measuring the dynamic contact angle of geotechnical materials according to claim 1, characterized in that: The guard ring, base and pressure head constitute a sample press for preparing reshaped samples; the small ring cutter is used for preparing original samples, and the outer side of the upper edge thereof has a cutting structure with the cutting blade facing upward, so as to facilitate cutting of original samples; the rock and soil sample (16) is placed downward with the cutting portion, and is tightly fitted with the protruding slot on the second rotating disk to ensure that the position does not change during rotation.

8. The device for measuring the dynamic contact angle of geotechnical materials according to claim 1, characterized in that: The rotating shaft (6) is composed of a degree shaft (19a), a minute shaft (19b) and a second shaft (19c). Each shaft is connected to the motor Ma (9). The rotating disks are connected by shafts on the side close to the motor Ma (9) and are connected by a driven shaft (7) on the far side. The three shafts are all sleeve-shaped. The degree shaft (19a) is on the outermost side, and one end is connected to the degree rotating disk; the minute shaft (19b) is on the inner side of the degree shaft (19a) and the outer side of the second shaft (19c), and one end is connected to the minute rotating disk; the second shaft (19c) is on the innermost side, and one end is connected to the second rotating disk. When the degree shaft (19a) rotates one circle, the rotating platform (4) rotates 360°; when the minute shaft (19b) rotates one circle, the rotating platform (4) rotates 360′; when the second shaft (19c) rotates one circle, the rotating platform (4) rotates 360″, and the degree shaft The second shaft (19c) is sleeved on the outer side of the second shaft (19a), and the second shaft (19b) is sleeved on the outer side of the second shaft (19c). The rotating rod (20) of the motor Ma (9) is provided with four sheet-shaped buckles (21), and each shaft is provided with a slot matching each buckle (21). When the degree shaft (19a) needs to be rotated, the buckle (21) is directly extended to the outermost side; when the second shaft (19b) needs to be rotated, the buckle (21) is extended to the inner side of the degree shaft (19a); when the second shaft (19c) needs to be rotated, the buckle (21) is extended to the innermost side, thereby ensuring that the rotation of the degree shaft (19a) will drive the second shaft (19b), but the rotation of the second shaft (19b) will not drive the degree shaft (19a), and the rotation of the second shaft (19b) will drive the second shaft (19c), but the rotation of the second shaft (19c) will not drive the second shaft (19b).

9. The measuring method using the geotechnical material dynamic contact angle measuring device according to claim 1 is characterized in that: The steps include: Step 1: Level the device and apply lubricating oil to each translation and rotation point to ensure uniform sliding and rotation during the test; Step 2: preparing a rock and soil sample (16); Step 3: Fill the liquid required for the test into the liquid bottle, install it on the precision fixture, adjust the threaded piston, and exhaust the gas in the liquid bottle; Step 4: placing the rock and soil sample (16) on the second rotating disk of the rotating platform (4), controlling the motors Mb, Mc, and Md, and adjusting the positions of the rock and soil sample (16) and the dropper so that the large aperture high-definition digital camera (15) can be clearly focused; Step 5: Turn on the large aperture high-definition digital camera (15) to start recording, control the motor Me (14), push the threaded piston, and drip a drop of the designed volume onto the rock and soil sample (16); Step 6: Control the motor Ma (9) to quickly rotate the degree, minute and second rotation disk to record the shape and movement trajectory of the droplet. When the droplet becomes unstable, stop recording; Step 7: Control the motors Mc and Md to repeat steps 5 and 6 at other positions of the sample to obtain control results and eliminate the influence of accidental factors on the test results; Step 8: Data analysis: compile an application for measuring the dynamic contact angle of geotechnical materials based on the image recognition toolbox, and use the image data captured in steps 5 and 6 to obtain the dynamic contact angle of geotechnical materials.

10. The measuring method according to claim 9, characterized in that: The method for preparing the rock and soil sample (16) is as follows: a small ring cutter is placed in a base, a protective ring is put on, a dry soil sample and water of a calculated mass are placed in the ring cutter, a pressure head is pressed, and a sample press is placed in a hydraulic jack reaction force frame, and a hydraulic jack is used to press the sample press. The pressure head is pressurized to 5MPa for 3min to obtain the reshaped sample required for the test. When the original sample is prepared, Directly sample with a small ring knife.

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