Novel rock-soil body disintegration test system and test method

Abstract

The invention discloses a novel rock-soil body disintegration test system and a test method.The test system comprises a water body filtering system, a temperature and humidity control system, a quality acquisition system and an image acquisition system, and the water body filtering system comprises a test box body, a box cover, a filtering device, fan blades and a flow stabilizing net; the temperature and humidity control system comprises a temperature controller and a humidity control system, the quality acquisition system comprises a hydrostatic electronic balance, a computer acquisition system, a sample container, a motor height controller and a limiter, and the image acquisition system comprises a camera used for acquiring the change process of a sample in the immersion disintegration process. According to the test system disclosed by the invention, automatic collection is added into the hydrostatic electronic balance while automatic lifting of the sample is realized, so that the defect of low collection precision of a tension meter can be effectively avoided, and the situation that the disintegration rate of a subsequent sample is influenced by the ion concentration change of a solution after repeated disintegration of the sample can also be avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of geotechnical engineering analysis and testing, and particularly relates to a new type of geotechnical disintegration test system and test method. Background Technique

[0002] The immersion disintegration test of geotechnical materials is an experimental method for studying the disintegration and failure of soil under immersion conditions, aiming to evaluate the stability and erosion resistance of soil or rock under different conditions. The immersion disintegration test of geotechnical materials aims to study the disintegration and failure behavior of soil under immersion conditions. In this test, soil samples in different saturation states are first prepared and then immersed in water to simulate the situation of soil being eroded by water in the natural environment. By observing the disintegration of the soil during the immersion process and recording the disintegration time, degree, form and characteristics, the stability and erosion resistance of the soil can be evaluated. The disintegration rate data obtained from the immersion disintegration test can be used to analyze the disintegration speed of the soil under specific conditions, providing important references for engineering design, prevention and control of geological disasters, and research on soil erosion. However, in the current disintegration tests, the manual operation error is relatively large, and the influence of complex temperature environments and wet-dry cycles in the natural environment on the disintegration of geotechnical materials cannot be simulated. Summary of the Invention

[0003] The purpose of the present invention is to provide a new type of geotechnical disintegration test system to solve the problems raised in the background technique.

[0004] To achieve the above object, the present invention provides a new type of geotechnical disintegration test system, including a water filtration system, a temperature and humidity control system, a mass acquisition system, and an image acquisition system. The water filtration system includes a test box body, a box cover, a filtration device, a wind blade, a steady flow net, a semi-permeable membrane, and a solution exchange system. The inlet of the filtration device is connected to the outlet of the test box body, the outlet of the filtration device is connected to the inlet of the semi-permeable membrane and solution exchange system, and the outlet of the semi-permeable membrane and solution exchange system is connected to the inlet of the test box body. The wind blade is arranged at the bottom inside the test box body. The number of the steady flow nets is two, and the two steady flow nets are horizontally arranged at intervals up and down in the test box body and are respectively located above and below the inlet of the test box body. The temperature and humidity control system includes a temperature controller and a humidity control system, and the temperature controller and the humidity control system are used to measure the temperature and humidity inside the test box body. The mass acquisition system includes a hydrostatic electronic balance, a computer acquisition system, a specimen container, a motor, a motor height controller, and a limiter. The hydrostatic electronic balance is arranged on a platform above the test box body. The specimen container is connected to the hook of the hydrostatic electronic balance and the motor height controller. The motor height controller is connected to the motor. The limiter is arranged on the hook of the hydrostatic electronic balance and is used to lock the height of the specimen container. The image acquisition system includes a camera, and the camera is arranged on one side of the test box body and is used to collect the change information of the specimen during the immersion disintegration experiment.

[0005] Further, the test box body is a transparent structural box body, and the temperature tolerance of the test box is -10 to 90 °C. The bottom of the specimen container is provided with a filtration hole.

[0006] The present invention also provides a new type of geotechnical immersion disintegration test method, which uses the above-mentioned geotechnical disintegration test system for the test. The method includes:

[0007] Making a ring knife sample or an undisturbed ring knife sample by static compaction, demolding, and moisturizing for standby. Adding a test liquid into the test box body, turning on the temperature controller to make the temperature of the test liquid reach a preset temperature. Turning on the wind blade and the filtration device, and putting the specimen into the specimen container.

[0008] Turning on the hydrostatic balance to start collecting data, turning on the limiter installed on the hook of the hydrostatic balance, controlling the motor to make the specimen container descend rapidly and uniformly. When the specimen container is completely immersed in the test liquid, locking the height of the specimen container through the limiter. The control system controls the image acquisition system to start taking pictures and collecting, and monitors the disintegration form of the specimen during the disintegration process.

[0009] Further, the acquisition frequency of the hydrostatic balance is 0.8 to 1.2 seconds / time.

[0010] The present invention also provides a new method for testing the disintegration of rock and soil masses upon immersion in water. The test is carried out using the above-mentioned rock and soil mass disintegration test system. The method includes:

[0011] A ring knife sample or an undisturbed ring knife sample is prepared by static compaction, demolded, and kept moist for standby. The sample is placed in a sample container, and no test liquid is injected into the test box. The chain of the sample container is passed through the hole in the box cover, and then the box cover is placed on the test box. First, the temperature controller and the humidity control system are turned on, and then the fan is turned on to make the temperature and humidity in the test box uniform and accelerate the temperature and humidity balance inside and outside the sample. Different temperatures or humidities are set as needed. For the temperature cycle, the temperature is increased in a temperature gradient to 50 °C and then decreased to room temperature as one cycle. For the humidity cycle, the humidity is increased to 100% and then decreased to 0% as one cycle. When the frequency of the temperature cycle or the wet-dry cycle reaches a certain level, the sample undergoes weathering disintegration, and the image acquisition system takes pictures to collect the disintegration form of the sample during the disintegration process.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] A novel geotechnical disintegration test system of the present invention is connected to a sample container through a motor, and then the force condition of the connecting line is adjusted through a limiter. While realizing the automatic lifting of the sample, by adding automatic acquisition in the hydrostatic balance, the disadvantage of low accuracy in collecting by a tensiometer is avoided; a water filtration system is added. During the disintegration test process, due to the disintegration and dropping of the soil body, it will cause the turbidity of the water body and the accumulation of residues, affecting the clarity of the images captured by the image acquisition system. The filtration device can not only discharge the large-particle residues in the water body but also filter and purify the small particles suspended in the water; the disintegration of the soil sample will be affected by the size of the water body ion concentration and the pH value. When studying the influence of pure aqueous solution on the disintegration of the soil body, after the soil body disintegrates into pure water, the mineral components in the soil body will affect the pH value and ion concentration of the pure water. When studying the test of the influence of the rated concentration of salt ions on the disintegration of the soil body, the mineral components of the soil body and its own water content will also affect the size of the ion concentration. In order to avoid frequent solution replacement and take into account economy and convenient and fast operation, the semi-permeable membrane and solution exchange system can block salt ions as needed, screen and retain salt ions like soil particles, ensuring that the filtered solution does not contain salt ions; on the other hand, when maintaining the rated salt solution, the semi-permeable membrane and solution exchange system can supplement or dilute the test solution according to the size of the real-time solution concentration / pH (the system contains an ion concentration meter, two storage chambers for pure water and saturated salt solution / acid-base solution, and adjusts the dispensing amount according to needs), so as to achieve the purpose of adjusting the pH value and ion concentration of the water body. By rotating the wind blades in the water tank, the residues and fine particles flow into the pipeline of the filtration system. A double-layer steady flow net is arranged in the water tank. While ensuring that the residues can pass smoothly, it is ensured that the water body fluctuation generated by the rotation of the wind blades does not affect the disintegration of the soil body; the wet-dry cycle disintegration test under temperature-humidity control can simulate the weathering disintegration test of the sample under different wet-dry cycle times and different temperature-humidity conditions, and can also simulate the immersion disintegration test under different temperature conditions.

[0014] A novel geotechnical disintegration test method of the present invention simulates the disintegration process of geotechnical bodies under complex temperature and humidity environments, while achieving accuracy and intelligence, and also taking into account simplicity and economy.

[0015] In addition to the purposes, features and advantages described above, the present invention has other purposes, features and advantages. The following will refer to the drawings to further elaborate on the present invention in detail. Description of the Drawings

[0016] The drawings are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present invention, but do not constitute a limitation to the embodiments of the present invention. In the drawings:

[0017] Figure 1 is a structural schematic diagram of a novel geotechnical disintegration test system of the present invention;

[0018] Among them, 1 - test box; 2 - box cover; 3 - filtering device; 4 - fan blade; 5 - flow stabilizing net; 6 - temperature controller; 7 - humidity control system; 8 - hydrostatic electronic balance; 9 - computer acquisition system; 10 - specimen container; 11 - motor height controller; 12 - limiter; 13 - bearing platform; 14 - camera; 15 - specimen; 16 - semipermeable membrane and solution exchange system. Specific implementation manners

[0019] The present invention will be described in detail below in conjunction with the various implementation manners shown in the accompanying drawings. However, it should be noted that these implementation manners do not limit the present invention. Any equivalent transformation or substitution in terms of function, method, or structure made by those of ordinary skill in the art according to these implementation manners shall fall within the protection scope of the present invention.

[0020] Please refer to Figure 1 , this embodiment provides a new type of geotechnical disintegration test system, including a water body filtering system, a temperature and humidity control system, a mass acquisition system, and an image acquisition system. The specific structure is as follows:

[0021] The water body filtering system consists of a test box 1, a box cover 2, a filtering device 3, a semipermeable membrane and solution exchange system 16, a fan blade 4, and a flow stabilizing net 5. The test box 1 is an organic glass water tank with a large depth and a relatively thick tank body, capable of withstanding high and low temperatures from -10°C to 90°C. The box cover 2 is used to cooperate with the test box 1. The box cover 2 is not required during immersion disintegration, and the box cover 2 is required during dry-wet cycling or weathering disintegration tests under certain humidity conditions. There is a hole in the middle of the box cover 2, which does not affect the operation of the hydrostatic electronic balance 8. The inlet of the filtering device 3 is connected to the outlet of the test box 1, the outlet of the filtering device is connected to the inlet of the semipermeable membrane and solution exchange system 16, and the outlet of the semipermeable membrane and solution exchange system 16 is connected to the inlet of the test box 1. The filtering device includes a pump and a filter net. The fan blade 4 is arranged at the bottom inside the test box 1, used as a stirrer to agitate the liquid when there is liquid, and as a fan to adjust the temperature inside the tank when there is no liquid. The number of flow stabilizing nets 5 is two layers, and the two layers of flow stabilizing nets 5 are horizontally arranged at intervals up and down inside the test box 1, and are respectively located above and below the inlet of the test box 1.

[0022] The temperature and humidity control system includes a temperature controller 6 and a humidity control system 7. The temperature adjustment range of the temperature controller 6 is from room temperature to 100°C. By controlling the external environmental temperature to reach a temperature below room temperature, such as an air conditioner or a temperature chamber, the organic glass tank can be controlled at a rated temperature, and a temperature cycling test can also be carried out. The humidity control system 7 is used to measure the humidity inside the test box 1, and the humidity adjustment range is 0 - 100%, so that the organic glass tank can be controlled at a rated humidity to achieve the effect of dry-wet cycling.

[0023] The mass acquisition system includes a hydrostatic electronic balance 8, a computer acquisition system 9, a specimen container 10, a motor (not shown in the figure), a motor height controller 11, and a stopper 12. The hydrostatic electronic balance 8 is arranged on a bearing platform 13 above the test box body 1. The specimen container 10 is connected to the hook of the hydrostatic electronic balance 8 and the motor height controller 11. The motor height controller 11 is connected to the motor. The stopper 12 is arranged on the hook of the hydrostatic electronic balance 8 and is used to lock the height of the specimen container 10. The motor height controller 11 is used to adjust the height of the specimen container 10. After the chain is locked, it cannot move. The hydrostatic electronic balance is only affected by the mass in the vertical direction. The mass of the system has deducted the mass influence of the chain between the stopper and the motor. Before the experiment starts, the stopper is opened to make the specimen descend uniformly into the water tank under the control of the motor. After it is completely immersed, the stopper locks. After the test ends, the stopper is opened to lift the specimen.

[0024] The image acquisition system includes a camera 14. The camera 14 is arranged on one side of the test box body 1 and is used to collect the change information of the specimen 15 during the immersion and disintegration process.

[0025] The present invention also provides a new method for testing the immersion and disintegration of geotechnical bodies. The test is carried out using the above-mentioned geotechnical body disintegration test system. The method includes:

[0026] Experimental preparation steps: A ring knife sample or an undisturbed ring knife sample is made by static compaction and demolded and kept moist for standby; pure water (salt solutions or liquids with different pH values according to the test requirements) is added to the test box body 1; the temperature controller 6 is turned on to make the liquid temperature reach the preset temperature. For example, disintegration tests are set under different temperature conditions, and the temperature gradient is 20, 25, 30, 35, 40 °C, etc. The blower 4 and the filtering device 3 are turned on. A double-layer steady flow net is arranged in the water tank. While ensuring that the residue can pass through smoothly, it is ensured that the water body fluctuation generated by the rotation of the blower does not affect the disintegration of the soil body. The specimen 15 is placed into the specimen container 10 to prepare for the disintegration test.

[0027] Immersion and disintegration test steps: The hydrostatic balance 8 is turned on to start collecting data (the collection frequency is 1 second / time). The stopper 12 installed on the hook of the hydrostatic balance 8 is opened, and the motor is controlled to make the specimen container 10 descend quickly and uniformly. When the specimen container 10 is completely immersed in the liquid, the stopper 12 is locked; the control system controls the image acquisition system to start taking pictures and collecting, and monitors the disintegration form of the specimen 15 during the disintegration process. The residue falling off during disintegration and the suspended particles in the liquid are continuously purified by the filtering system, making the water body in the water tank clean and clear, ensuring a good image acquisition environment, and also avoiding the waste of replacing the water body, especially for specific solution tests. While improving the efficiency of the disintegration test, it reduces resource waste. The pH value and ion concentration of the water body can be adjusted through the purification system as needed.

[0028] The present invention also provides a new method for testing the disintegration of rock and soil masses when soaked in water. The disintegration test of the rock and soil masses under wet-dry cycling / temperature cycling is carried out by using the above-mentioned disintegration test system for rock and soil masses. The method includes:

[0029] Experimental preparation steps: A core sample or an undisturbed core sample is prepared by static compaction and demolded and kept moist for standby. The specimen 15 is placed into the specimen container 10, and no test liquid is injected into the test chamber 1. The chain of the specimen container 10 is passed through the hole in the lid 2 of the chamber, and then the lid 2 is covered on the test chamber 1. First, the temperature controller 6 and the humidity control system 7 are turned on, and then the fan blade 4 is turned on to make the temperature and humidity in the test chamber 1 uniform and accelerate the temperature and humidity balance inside and outside the specimen 15. Different temperatures or humidities are set as required. For temperature cycling, it is one cycle that the temperature is increased to 50 °C with a temperature gradient and then decreased to room temperature. For humidity cycling, it is one cycle that the humidity is increased to 100% and then decreased to 0%. During the drying period, the temperature of the water tank can be increased to accelerate the water loss rate.

[0030] Natural weathering disintegration test under wet-dry cycling / temperature cycling: When the frequency of temperature cycling or wet-dry cycling reaches a certain level, the specimen 15 undergoes weathering disintegration. During a certain moisture absorption or temperature increase process, the specimen will undergo weathering disintegration. At this time, the test system of the present invention can monitor the mass change of the specimen, and the image acquisition system takes pictures to collect the disintegration form of the specimen during the disintegration process to simulate the disintegration situation of the specimen under long-term environmental loads. At the same time, the disintegration test when soaked in water can also be carried out after multiple temperature / wet-dry cycles.

[0031] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A new type of rock and soil disintegration testing system, characterized in that: The invention comprises a water filtering system, a temperature and humidity control system, a quality acquisition system and an image acquisition system. The water filtering system comprises a test box (1), a box cover (2), a filtering device (3), a fan blade (4), a flow stabilizing net (5) and a semipermeable membrane and a solution exchange system (16). The inlet of the filtering device (3) is connected to the outlet of the test box (1), the outlet of the filtering device (3) is connected to the inlet of the semipermeable membrane and the solution exchange system (16), and the outlet of the semipermeable membrane and the solution exchange system (16) is connected to the inlet of the test box (1); the fan blade (4) is arranged at the bottom of the test box (1); the flow stabilizing net (5) is provided in two layers, and the two layers of the flow stabilizing net (5) are horizontally arranged in the test box (1) with an interval between the upper and lower layers, and are respectively located above and below the inlet of the test box (1); the temperature and humidity control system comprises a temperature controller (6) and a humidity control system (7). The device (6) and the humidity control system (7) are used to measure the temperature and humidity in the test box (1); the mass acquisition system comprises a hydrostatic electronic balance (8), a computer acquisition system (9), a sample container (10), a motor, a motor height controller (11) and a stopper (12); the hydrostatic electronic balance (8) is arranged on a support platform (13) above the test box (1); the sample container (10) is connected to a hook of the hydrostatic electronic balance (8) and the motor height controller (11); the motor height controller (11) is connected to the motor; the stopper (12) is arranged on the hook of the hydrostatic electronic balance (8) and is used to lock the height of the sample container (10); the image acquisition system comprises a camera (14); the camera (14) is arranged on one side of the test box (1) and is used to acquire information on changes in the sample (15) during the water immersion disintegration experiment.

2. The rock and soil disintegration testing system according to claim 1, characterized in that: The test box (1) is a transparent structure box, and the test box (1) has a tolerable temperature of -10 to 90° C.; a filtering hole is provided at the bottom of the sample container (10).

3. A new method for testing the disintegration of rock and soil under immersion, characterized in that: The rock and soil mass disintegration test system according to claim 1 or 2 is used to conduct a test, and the method comprises: A ring knife sample or an original ring knife sample is obtained by static compaction and demoulding to keep it moist for later use; a test liquid is added to a test box (1), and a temperature controller (6) is turned on to make the temperature of the test liquid reach a preset temperature; a fan blade (4) and a filter device (3) are turned on, and a sample (15) is placed in a sample container (10); The hydrostatic balance (8) is turned on to start collecting data, the stopper (12) installed on the hook of the hydrostatic balance (8) is turned on, and the motor is controlled to make the sample container (10) descend rapidly and uniformly. When the sample container (10) is completely immersed in the test liquid, the height of the sample container (10) is locked by the stopper (12); the control system controls the image acquisition system to start taking pictures and collecting data, and monitors the disintegration form of the sample (15) during the disintegration process.

4. The method for testing the disintegration of rock and soil bodies by immersion in water according to claim 3, characterized in that: The acquisition frequency of the hydrostatic balance (8) is 0.8 to 1.2 seconds per time.

5. A new method for testing the disintegration of rock and soil under immersion, characterized in that: The rock and soil mass disintegration test system according to claim 1 or 2 is used to conduct a test, and the method comprises: A ring knife sample or an original ring knife sample is obtained by static compaction and demoulding to keep the sample moist for standby use. The sample (15) is placed in a sample container (10). No test liquid is injected into the test box (1). The chain of the sample container (10) is passed through the hole of the box cover (2), and the box cover (2) is then placed on the test box (1). First, the temperature controller (6) and the humidity control system (7) are turned on, and then the fan blade (4) is turned on to make the temperature and humidity in the test box (1) uniform and accelerate the temperature and humidity balance inside and outside the sample (15). Different temperatures or humidities are set as needed. The temperature cycle is performed by increasing the temperature gradient to 50°C and then decreasing it to room temperature for one cycle, and the humidity cycle is performed by increasing the humidity to 100% and then decreasing it to 0% for one cycle. When the temperature cycle or the dry-wet cycle frequency reaches a certain level, the sample (15) weathers and disintegrates, and the image acquisition system takes photos to collect the disintegration form of the sample (15) during the disintegration process.

Images