A device and method for testing the swelling force of viscous sliding zone soil

Abstract

The present invention discloses a device and method for testing the swelling force of viscous sliding belt soil, including an instrument test bench, a volume adjustment and expansion device, an expansion test cylinder, a sensor device assembly, a data acquisition system and a liquid injection device. The instrument test bench provides test environment conditions, the expansion test cylinder is installed on the laboratory table of the instrument test bench, and the upper honeycomb pad cooperates with the lifting rod to achieve the sample preparation target. After the liquid injection device injects water from the liquid inlet at the bottom of the expansion test cylinder, the axial swelling force, annular swelling force and temperature monitored by the sensor device assembly are recorded and stored in real time by the data acquisition system. The present invention can realize the swelling force test of viscous sliding belt soil under different physical property state conditions and environmental state conditions, including axial swelling force and annular swelling force, and the test data is recorded and stored by the data acquisition system, with higher test accuracy, simpler test conditions and more test property objects.

Description

Technical Field

[0001] The present invention belongs to the technical field of geotechnical engineering tests, and relates to a quantitative test of the swelling force of viscous sliding zone soil, and in particular to a device and method for testing the swelling force of viscous sliding zone soil formed by the sliding of a slope along a soft layer controlled by a coal-bearing stratum, a bauxite stratum, and a soft stratum dominated by expansive minerals. Background Art

[0002] Landslide geological disasters are the main type of disasters that affect the survival and development of human beings around the world. How to control and reduce the occurrence of landslides has become a scientific and technological problem that needs to be solved urgently. Landslide belt soil is one of the important components of landslides. Among them, there is a type of clayey landslide belt soil that is different from general landslide belt soil. Because it contains a large amount of clay minerals and has the property of absorbing water and swelling, it is called viscous landslide belt soil. This type of landslide belt soil is often formed by the sliding of slopes controlled by coal-bearing strata, bauxite strata, and soft strata dominated by swelling minerals along the weak layer. Quantitative testing and research on the swelling force generated by the swelling of viscous landslide belt soil will have important theoretical basis for the study of the causal mechanical mechanism of landslides.

[0003] In the prior art, the patent number CN215677902U provides a swelling rock hydration swelling force testing device, including a mechanical test structure, a pressure structure, a pressure recorder and a computer system for data analysis, wherein the mechanical test structure includes a frame, a test force sensor placed in the frame and a pressure structure, wherein the pressure structure pressurizes a test piece placed in the pressure structure through a lower pressurizing device, wherein the test piece is placed in a supporting frame and is placed in an upper pressure water tank in the pressure structure via the supporting frame, wherein the pressure structure also includes a lower pressure water tank connected to the upper pressure water tank, so as to realize swelling force testing of swelling rocks under different water pressures; the computer system and the test force sensor of the rock mechanics test system are used to collect test data in real time, with a high degree of automation, which greatly reduces the labor intensity of test personnel, and at the same time, the test process is less affected by human factors and has high test accuracy. Patent number CN214583761U provides a comprehensive detection device for lateral expansion force and expansion rate of expansive rock and soil, including a box fixed on the surface of the test table, one side of the box is provided with an opening, and the opening is provided with a movable baffle that can move in the box, one side of the movable baffle is against the expansive rock and soil in the box, and the other side is installed with a detachable expansion force measuring mechanism, and the expansion force measuring mechanism is replaced by a detachable deformation measuring mechanism after the measurement is completed. The detection device can effectively improve the accuracy of the measurement result by monitoring the expansion force and expansion deformation of the expansive rock and soil, and then deriving the law between the deformation and the expansion force release. The device also has the advantages of simple detection method, convenient test process, low manufacturing cost, convenience and practicality, and high safety, and can provide strong data support for actual engineering design analysis.

[0004] In summary, in order to quantitatively test the swelling force of viscous sliding zone soil in landslide geological disasters, the existing technology mainly uses bentonite as the research object to carry out the research on swelling force testing devices, and simply explores the swelling force, swelling rate and other properties of bentonite under different environmental conditions. However, viscous sliding zone soil is different from bentonite under normal conditions. In addition to being in different environmental conditions, it also has different physical property conditions such as different clay mineral component content ratios, specimen size, initial moisture content and dry density. At present, there is no swelling force testing device that can simultaneously adjust different physical property conditions and environmental conditions. Summary of the invention

[0005] The purpose of the present invention is to provide a swelling force testing device and a testing method for viscous sliding belt soil, which can realize the swelling force testing of viscous sliding belt soil under different physical property state conditions and environmental state conditions, fill the current gaps in related technologies, and can solve the problem in the prior art of lack of swelling force testing devices that can simultaneously adjust different physical property state conditions and environmental state conditions.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a device for testing the swelling force of viscous sliding zone soil, comprising:

[0008] A test bench, wherein an expansion test cylinder is arranged on the test bench, wherein a liquid inlet is arranged at the bottom of the expansion test cylinder, and a liquid outlet is arranged at the top;

[0009] A volume regulating and expansion device, the volume regulating and expansion device comprises a driving mechanism, an upper piston assembly and a lower piston assembly, the upper piston assembly comprises an upper honeycomb pad and an upper piston rod, the upper honeycomb pad is arranged at the upper part of the cylinder cavity of the expansion test cylinder, and the upper piston rod is connected to the upper surface of the upper honeycomb pad; the lower piston assembly comprises a lower honeycomb pad and a lower piston rod, the lower honeycomb pad is arranged at the lower part of the cylinder cavity of the expansion test cylinder, and the lower piston rod is connected to the lower surface of the lower honeycomb pad, a sample space for accommodating a test soil sample is formed between the upper honeycomb pad, the lower honeycomb pad and the cylinder wall of the expansion test cylinder, at least one of the upper piston rod and the lower piston rod is connected to the driving mechanism, and the driving mechanism can make the upper honeycomb pad and the lower honeycomb pad approach or move away from each other to adjust the volume of the sample space; permeable stone plates are arranged between the test soil sample and the upper honeycomb pad and between the test soil sample and the lower honeycomb pad to intercept the test soil sample in the sample space during the test;

[0010] A liquid injection device, the liquid injection device is connected to the liquid inlet through a pipeline, and is used to inject a test liquid into the expansion test cylinder, and the temperature and injection flow rate of the test liquid are adjustable;

[0011] A sensing device assembly, the sensing device assembly comprising an axial expansion force detection device, a circumferential expansion force detection device and a temperature detection device, the circumferential expansion force detection device and the temperature detection device being arranged on the expansion test cylinder; the axial expansion force detection device can detect the expansion force exerted on the upper piston assembly and the lower piston assembly;

[0012] A data acquisition system is communicatively connected with the liquid injection device, the driving mechanism, the axial expansion force detection device, the annular expansion force detection device and the temperature detection device.

[0013] Optionally, the test bench comprises:

[0014] load-bearing platform;

[0015] A test bench, the test bench being arranged on the upper surface of the load-bearing platform;

[0016] A leveling support rod, wherein the leveling support rod is arranged on the upper surface of the experimental bench, and a plurality of leveling support rods are evenly arranged, and the bottom ends of all the leveling support rods are threadedly connected to the experimental bench, and the expansion test cylinder is arranged above the leveling support rod and connected to the top ends of all the leveling support rods.

[0017] Optionally, the lower piston rod is arranged to penetrate the bottom of the expansion test cylinder, and the lower piston rod and the expansion test cylinder are sealed by a pan seal, and the pan seal is fixed to the bottom of the expansion test cylinder by a fixing cap; wherein the bottom end of the lower piston rod is connected to the test bench through the axial expansion force detection device, and the top end of the lower piston rod is connected to the lower honeycomb pad;

[0018] The top end of the upper piston rod is connected to the driving mechanism through the axial expansion force detection device.

[0019] Optionally, it further includes a top plate, which is supported on the experimental table by a support rod and is located above the expansion test cylinder; the driving mechanism includes:

[0020] A hollow straight cylinder, wherein the hollow straight cylinder is arranged on the upper surface of the top plate;

[0021] A lifting rod, wherein the lifting rod is slidably sleeved in the hollow straight cylinder, and the bottom end of the lifting rod passes through the top plate, and the top end of the lifting rod is used to connect to a lifting power source;

[0022] A mounting disc, the upper surface of which is detachably connected to the bottom end of the lifting rod, the top end of the upper piston rod is connected to a tray, the lower surface of which is detachably connected to the tray; the mounting disc is provided with the axial expansion force detection device, which can detect the expansion force exerted on the upper piston assembly;

[0023] The lifting rod fixing bolt is arranged through the side wall of the hollow straight cylinder, and the lifting rod fixing bolt is threadedly connected to the side wall of the hollow straight cylinder, and the tail of the lifting rod fixing bolt can extend into the hollow straight cylinder and tighten the lifting rod.

[0024] Optionally, four lifting rod fixing bolts are evenly arranged along the circumference of the hollow straight cylinder. Any of the lifting rod fixing bolts is arranged perpendicular to the axial direction of the hollow straight cylinder.

[0025] Optionally, the side wall of the expansion test cylinder is provided with a slit viewport extending along its axial direction, and the slit viewport is connected to the cylinder cavity of the expansion test cylinder; a transparent glass plate is sealed in the slit viewport to observe the changes in the liquid level in the expansion test cylinder; and a liquid level scale is also provided on the outside of the slit viewport.

[0026] Optionally, the sensing device assembly further includes an image acquisition device, a micrometer and a spirit level, wherein the image acquisition device, the micrometer and the spirit level are all communicatively connected to the data acquisition system, wherein the image acquisition device is used to record the height of the liquid level rise through the slit viewport in real time, the micrometer is arranged on the support rod, and the spirit level is arranged on the top of the mounting disc and the expansion test cylinder.

[0027] Optionally, a plurality of mounting holes are provided on the side wall of the expansion test cylinder opposite to the slit viewport, and all of the mounting holes are distributed along the axial direction of the expansion test cylinder; any one of the mounting holes is connected to the cylinder cavity of the expansion test cylinder, the annular expansion force detection device is installed at the inner ends of some of the mounting holes, and the temperature detection device is installed at the inner ends of the remaining mounting holes; the outer end of any one of the mounting holes is threadedly connected with a hollow screw to seal the mounting hole; wherein the hollow screw is formed by connecting two semi-hollow screws, and the data cable of the annular expansion force detection device or the temperature detection device is embedded in the inner cavity of the hollow screw.

[0028] Optionally, grooves are provided on the outer circumferences of the upper honeycomb pad and the lower honeycomb pad, and a plurality of steel balls are embedded in the grooves. The outer circumferences of the upper honeycomb pad and the lower honeycomb pad are slidably matched with the inner cylinder wall of the expansion test cylinder through the steel balls.

[0029] At the same time, the present invention proposes a method for testing the swelling force of viscous sliding zone soil using the above-mentioned viscous sliding zone soil swelling force testing device, comprising:

[0030] Step 1, laying the permeable stone slab on the upper honeycomb pad, placing a test soil sample of target dry density mass into the expansion test cylinder, removing the mounting disc, and driving the lifting rod to descend to compact the test soil sample to form a block test soil sample;

[0031] Step 2, placing the permeable stone plate and the upper honeycomb pad connected with the upper piston rod and the tray in sequence above the block test soil sample, installing the mounting disc and driving the lifting rod to descend until the mounting disc is connected with the tray, and fixing the position of the lifting rod;

[0032] Step 3, clearing the axial expansion force detection device, the circumferential expansion force detection device and the temperature detection device;

[0033] Step 4, injecting a test liquid into the expansion test cylinder to start a viscous sliding zone soil expansion force test experiment;

[0034] Step 5: Collect and save the data of the sensor device assembly through the data acquisition system;

[0035] Step 6, loosen the lifting rod, so that the axial expansion force generated by the block test soil sample drives the upper honeycomb pad to move upward, and at the same time, the axial expansion force, annular expansion force and temperature of the block test soil sample after liquid absorption are recorded in real time through the sensor device assembly;

[0036] Step 7: Discharge the test liquid in the expansion test cylinder through the liquid inlet.

[0037] Optionally, in step 1, the step of pressing the block test soil sample includes:

[0038] Step 11, placing a test soil sample of target dry density mass into the expansion test cylinder, and driving the lifting rod to descend to compact the test soil sample to form a first layer of block test soil sample;

[0039] Step 12: Place a test soil sample with the same target dry density mass on top of the first layer of block test soil samples, and drive the lifting rod to descend to compact the test soil sample again to form the block test soil sample.

[0040] Compared with the prior art, the present invention has achieved the following technical effects:

[0041] The device for testing the swelling force of viscous sliding belt soil proposed by the present invention comprises an instrument test bench, a volume adjustment and expansion device, an expansion test cylinder, a sensor device assembly, a data acquisition system and a liquid injection device. The instrument test bench provides test environment conditions, the expansion test cylinder is installed on the experimental table of the instrument test bench, and the upper honeycomb pad cooperates with the lifting rod to achieve the sample preparation target. After the liquid injection device injects water from the liquid inlet at the bottom of the expansion test cylinder, the axial swelling force, annular swelling force and temperature monitored by the sensor device assembly are recorded and stored in real time by the data acquisition system. The present invention can realize the swelling force test of viscous sliding belt soil under different physical property state conditions and environmental state conditions, including axial swelling force and annular swelling force. The test data is recorded and stored by the data acquisition system. The test accuracy is higher, the test conditions are simpler, and the test property objects are more. It has theoretical basis and application value for the study of the mechanical mechanism of landslide initiation.

[0042] The method for testing the swelling force of viscous sliding zone soil proposed in the present invention is implemented based on the above-mentioned device for testing the swelling force of viscous sliding zone soil. It has higher test accuracy, simpler test conditions, and more test attribute objects, and has theoretical basis and application value for the study of the mechanical mechanism of landslide initiation. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0044] Figure 1 It is a schematic diagram of the overall structure of a device for testing the swelling force of viscous sliding zone soil disclosed in an embodiment of the present invention;

[0045] Figure 2 It is a schematic diagram of the assembly structure between the hollow straight cylinder and the lifting rod fixing bolts in the viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0046] Figure 3 It is a schematic structural diagram of a hollow straight cylinder in a device for testing the swelling force of viscous sliding zone soil disclosed in an embodiment of the present invention;

[0047] Figure 4 It is an axial cross-sectional view of a hollow straight cylinder in a viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0048] Figure 5 It is a schematic diagram from a first perspective of a lifting rod fixing bolt in a viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0049] Figure 6It is a schematic diagram from a second perspective of a lifting rod fixing bolt in a viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0050] Figure 7 It is a schematic diagram of the connection structure between the lifting rod and the mounting disc in the viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0051] Figure 8 for Figure 7 Bottom view of

[0052] Fig. 9 It is a structural schematic diagram of a narrow slit viewport of an expansion test cylinder in a device for testing the expansion force of viscous sliding zone soil disclosed in an embodiment of the present invention;

[0053] Fig.10 for Fig. 9 DD profile diagram;

[0054] Fig.11 It is a schematic diagram of the structure of the perspective glass plate;

[0055] Fig.12 It is a structural schematic diagram of the mounting hole of the expansion test cylinder in the viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0056] Fig.13 for Fig.12 FF cross-section diagram;

[0057] Fig.14 It is a schematic diagram of the overall structure of the hollow screw in the viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0058] Fig.15 It is a schematic diagram of the half structure of the hollow screw in the viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0059] Fig.16 It is an axial schematic diagram of a half structure of a hollow screw in a device for testing the expansion force of viscous sliding belt soil disclosed in an embodiment of the present invention;

[0060] Fig.17 It is a schematic diagram of the structure of the bottom plate of the expansion test cylinder in the viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0061] Fig.18 for Fig.17 GG profile diagram;

[0062] Fig.19 It is a structural schematic diagram of an upper honeycomb pad in a viscous sliding zone soil expansion force testing device disclosed in an embodiment of the present invention;

[0063] Fig. 20 for Fig.19 II section view;

[0064] Fig.21 It is a schematic structural diagram of a hollow straight cylinder in a device for testing the swelling force of viscous sliding zone soil disclosed in an embodiment of the present invention;

[0065] Fig. 22 for Fig.21 JJ cross-section diagram.

[0066] Wherein, the accompanying drawings are marked as follows:

[0067] 1. Load-bearing platform; 2. Laboratory table; 3. Anchor screws; 4. Support rod; 5. Top plate; 6. Nuts; 7. Hollow straight cylinder; 8. Lifting rod fixing bolts; 9. Lifting rod; 10. Mounting disc; 11. Expansion test cylinder; 12. Transparent glass plate; 13. Slit viewport; 14-1. Hollow screws; 14-2. Mounting holes; 15. Leveling support rod; 16. Level; 17-1. Tray; 17-2. Upper piston rod; 17-3. Upper honeycomb pad; 17-4. Steel ball; 18. Permeable stone slab; 19. Test soil sample; 20-1. Fixing cap; 20-2. Hollow cylinder; 20-3. Pan seal; 21. Liquid inlet; 22. Liquid outlet; 23. Pressure sensor; 24. Micrometer; 25. Liquid injection device; 26. Data acquisition system; 27. Laptop computer. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0069] One of the purposes of the present invention is to provide a swelling force testing device for viscous sliding belt soil, which can realize the swelling force testing of viscous sliding belt soil under different physical property state conditions and environmental state conditions, filling the current gaps in related technologies and being able to solve the problem in the prior art of lack of swelling force testing devices that can simultaneously adjust different physical property state conditions and environmental state conditions.

[0070] Another object of the present invention is to provide a method for testing the swelling force of viscous sliding zone soil based on the above-mentioned swelling force testing device of viscous sliding zone soil.

[0071] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0072] Embodiment 1

[0073] like Figures 1 to 10 As shown, this embodiment provides a device for testing the swelling force of viscous sliding belt soil, which mainly includes an instrument test stand, an swelling test cylinder 11, a volume adjustment and swelling device, a sensor device assembly, a liquid injection device 25 and a data acquisition system 26. Among them:

[0074] The instrument test bench includes a load-bearing platform 1 and a laboratory bench 2. The laboratory bench 2 is installed on the upper surface of the load-bearing platform 1. The load-bearing platform 1 and the laboratory bench 2 are separated and provide different functions respectively. The load-bearing platform 1 is used to keep the center of gravity of the entire device stable. The laboratory bench 2 provides a stable installation and testing platform for the expansion test cylinder 11. The load-bearing platform 1 and the laboratory bench 2 are fixed together by anchor screws 3. The four corners of the laboratory bench 2 are support rods 4. The upper ends of the four support rods 4 are connected to the top plate 5 and fixed by nuts 6. The top plate 5 can fix the lifting rod 9 in the volume adjustment and expansion device (see the description of the lifting rod 9 below), and assist in playing the function of constant volume during the expansion test.

[0075] The volume adjustment and expansion device includes a driving mechanism, an upper piston assembly and a lower piston assembly. The upper piston assembly is used to test the axial expansion force and can also be called an "expansion piston". The upper piston assembly includes a tray 17-1, a piston rod 17-2, an upper honeycomb pad 17-3 and a steel ball 17-4. The tray 17-1 is in contact with the axial expansion force detection device. The length of the piston rod 17-2 can be replaced according to the volume requirements of the test object, thereby achieving the expansion force and expansion rate test of viscous sliding belt soil under different volume physical properties. The upper honeycomb pad 17-3 is a disc pad for water to pass smoothly. There are four circular holes in the middle. There is a groove on the front, back, left and right sides of the outer circumference of the upper honeycomb pad 17-3 for the installation of the steel ball 17-4. The steel ball 17-4 can reduce the friction between the upper honeycomb pad 17-3 and the wall of the expansion test cylinder 11 during the water absorption and expansion of the test soil sample 19, thereby reducing the experimental error. A circular permeable stone plate 18 is placed under the upper honeycomb pad; the lower piston assembly has the same structure as the above-mentioned upper piston assembly and is arranged at the bottom of the expansion test cylinder 11 to check the saturated weight and axial expansion force of the test soil sample 19; the expansion test cylinder 11, the upper honeycomb pad 17-3 and the driving mechanism can cooperate to realize the compaction function of the predetermined dry density of the test soil sample.

[0076] Furthermore, the driving mechanism of the present embodiment is essentially a lifting device, which includes a hollow straight cylinder 7 and a lifting rod 9. The hollow straight cylinder 7 and the top plate 5 are directly and firmly fixed together by spot welding. In order to keep the constant volume unchanged during the expansion test, the front, rear, left and right side walls of the hollow straight cylinder 7 are internally threadedly connected to the lifting rod fixing screws 8. Rotating and tightening the lifting rod fixing screws 8 can keep the lifting rod 9 stationary. After unscrewing the lifting rod fixing screws 8, the expansion force and expansion rate test of the free expansion of viscous sliding belt soil can be realized. A mounting disc 10 is provided at the lower end of the lifting rod 9. A horizontal centering instrument, namely a spirit level 16, is placed on the upper surface of the mounting disc 10 to ensure that the lifting rod 9 is in a vertical position during the test. The mounting disc 10 also provides a stable platform for the installation of the axial expansion force detection device. Among them, the axial expansion force detection device located at the top is installed on the lower surface of the mounting disc 10, and is used to directly contact the top of the piston rod 17-2 when the piston rod 17-2 is pressed down, or when the piston rod 17-2 rises under the action of the axial expansion force of the soil sample, so as to detect the axial expansion force exerted on the upper piston assembly.

[0077] The bottom plate of the expansion test cylinder 11 is connected to the test bench 2 through a leveling support rod 15, and the bottom end of the leveling support rod 15 is threadedly connected to the test bench 2. The horizontal position of the expansion test cylinder 11 can be changed by rotating a single or multiple leveling support rods 15 until the bubble of the level gauge 16 on the upper surface of the expansion test cylinder 11 is centered. A slit viewport 13 for observing the rising water level is opened on the left side of the expansion test cylinder 11. A transparent glass plate 12 is arranged in the slit viewport 13 to isolate the test soil sample 19 from leaking out. The transparent glass plate 12 can be a long strip of tempered curved glass. The rising water level can be observed in real time through the slit viewport 13. The right side of the expansion test cylinder 11 is provided with mounting holes 14-2 for the annular expansion force detection device and the temperature detection device. The inner end of each mounting hole 14-2 is connected to the cylinder cavity of the expansion test cylinder 11. The inner end of the mounting hole 14-2 is for the detection device to be installed, and the outer end is threadedly connected with a hollow screw 14-1. The hollow screw 14-1 serves to block the mounting hole 14-2 to prevent the water flow in the expansion test cylinder 11 from leaking out. At the same time, the hollow screw 14-1 also serves to axially tighten the detection device to prevent the detection device from shaking in the mounting hole. Among them, the hollow screw 14-1 is formed by connecting two semi-hollow screws, and the data line of the corresponding detection device in the mounting hole 14-2 is embedded in the cavity formed by the connection of the two semi-hollow screws. Among them, three mounting holes 14-2 are preferably provided, one or two of which are used to install the annular expansion force detection device, and the remaining ones are used to install the temperature detection device.

[0078] A piston rod movable circular hole is opened in the center of the bottom plate of the expansion test cylinder 11, and the lower piston rod of the lower piston assembly passes through the piston rod movable circular hole, and the two are sealed by a pan seal 20-3, which is sleeved in the piston rod movable circular hole, one end of which is a hollow cylinder 20-2, and the other end is fixed to the bottom plate of the expansion test cylinder 11 by bolts through a fixing cap 20-1. The outer wall of the lower piston rod fits tightly with the inner wall of the pan seal 20-3, and the bottom of the lower piston rod is connected to the test bench 2 through another axial expansion force detection device. The top of the lower piston rod is located in the cylinder cavity of the expansion test cylinder 11 and is connected to the lower honeycomb pad. When the lower honeycomb pad is compressed, the axial expansion force detection device can measure the axial expansion force of the entire lower piston assembly due to direct contact with the bottom end of the lower piston rod. When the horizontality of the expansion test cylinder 11 is adjusted by the leveling support rod 15, the expansion test cylinder 11 will move up and down relative to the lower piston rod. A liquid inlet 21 is opened at the bottom of the side wall of the expansion test cylinder 11, and a liquid outlet 22 is opened at the top side wall. The liquid inlet 21 and the liquid outlet 22 are arranged along the radial direction of the expansion test cylinder 11, and a water circulation channel is formed between the liquid inlet 21 and the liquid outlet 22.

[0079] The sensor equipment assembly mainly includes the above-mentioned axial expansion force detection device, circumferential expansion force detection device, temperature detection device, micrometer 24, and level 16. There are two axial expansion force detection devices, one is located on the above-mentioned mounting disc 10, which is used to contact the top of the upper piston rod, and the other is located on the experimental table 2, which can maintain contact with the bottom of the lower piston rod. The circumferential expansion force detection device and the temperature detection device are installed on the side wall of the expansion test cylinder 11 at the same time, which can realize synchronous monitoring and recording. The micrometer 24 is fixed on the support rod 4. Each component in the above-mentioned sensor equipment assembly is connected to the data acquisition system 26 for communication. The data acquisition system 26 can record the axial expansion force, circumferential expansion force, and temperature changes generated by the water absorption and expansion of the viscous sliding belt soil in real time, and also record the saturated water density of the test soil sample 19 recorded by the lower sensor. The above-mentioned axial expansion force detection device, circumferential expansion force detection device, and temperature detection device are preferably axial expansion force sensors, circumferential expansion force sensors, and temperature sensors, respectively. Both axial expansion force sensors can use pressure sensors 23.

[0080] The injection device 25 is a water injection seepage device, which is loaded with distilled water and is equipped with a heating device and a valve, etc. The heating device can control the temperature of the water flow discharged by the injection device 25, such as a water heater; the valve can control the water flow rate, such as a solenoid valve. The above-mentioned heating device and valve are both existing technologies and are not described here. By adjusting the water flow rate of the injection device 25, the expansion force and expansion rate test of the viscous sliding belt soil in a pressurized environment can be achieved, and by adjusting the water flow temperature, the expansion force and expansion rate test of the viscous sliding belt soil in different temperature environments can be achieved.

[0081] The data acquisition system 26 can be connected to the laptop computer 27 for communication, and the laptop computer 27 can store, further process and analyze the data collected by the data acquisition system 26 .

[0082] The viscous sliding belt soil expansion force testing device of this embodiment is specifically a viscous sliding belt soil expansion force testing device under different physical property state conditions and environmental state conditions. The testing device can change the clay mineral component content ratio, specimen size, initial moisture content and dry density of the test specimen, and can also provide environmental state conditions such as different pressures and different temperatures. The viscous sliding belt soil expansion force testing method using the above-mentioned viscous sliding belt soil expansion force testing device specifically includes the following steps:

[0083] Step 1: First, place a permeable stone plate 18 on the lower honeycomb pad at the bottom of the expansion test cylinder 1, apply vaseline to the inner wall of the expansion test cylinder 1, and prepare the test soil sample by static pressure method. To ensure the uniformity of the test soil sample, it is compacted in two layers. Use a precision electronic balance to weigh the test soil sample of the target dry density mass, pour it into the expansion test cylinder 1, and then sequentially install the permeable stone plate 18 and the upper honeycomb pad 17-3 on top of the test soil sample. At this time, the upper honeycomb pad 17-3 is equipped with a tray 17-1 and an upper piston rod 17-2, and the test soil sample is removed at the same time. In addition to the mounting disc 10 and the axial expansion force sensor at the bottom of the lifting rod 9, the lifting rod 9 is driven downward to drive the upper honeycomb pad 17-3 to be pressed down, so that the soil sample is compacted to the assumed dry density. The change in sample height can be measured as a verification standard, and the compacted height of the poured soil sample can be observed through the left slit viewport 13. When the height of the test soil sample stays at the 6 cm scale position, the first layer of sample compaction is completed; then pour in a test soil sample with the same target dry density mass, and adopt the same compaction method to obtain the final block test soil sample 19.

[0084] Step 2. After the loaded test soil sample 19 reaches the experimental assumptions, reinstall the mounting disc 10 and the axial expansion force sensor to the bottom of the lifting rod 9, and then the lifting rod 9 is freely lowered to be closely connected with the tray 17-1 on the top of the upper piston rod 17-2. The overburden pressure in this process has a certain impact on the test soil sample 19, which is mainly manifested in the reduction of its volume, porosity and other parameters. This process will also cause lateral pressure due to the overburden pressure. These are all experimental errors of the expansion force test. Therefore, it is necessary to stand for a period of time. After the detection values ​​of the relevant axial expansion force sensors, annular expansion force sensors, temperature sensors, etc. are stable, tighten the lifting rod fixing bolts 8 to fix the height position of the lifting rod 9 at this time. At this time, the interval between the upper honeycomb pad 17-3 and the lower honeycomb pad remains unchanged, thereby achieving the purpose of constant volume in the test.

[0085] Step 3: After the expansion test cylinder 11 is statically calibrated, in order to accurately test the quantitative results of the soil sample expansion force, the axial pressure and annular pressure generated during the static calibration process need to be cleared. This step is called instrument zeroing. In addition, the zeroing of the micrometer 24 can be based on the reading it stops at after the static calibration as the starting data.

[0086] Step 4: After the injection device 25 is filled with distilled water, its water temperature is heated to the set temperature, and the water outlet rate is set. After the water outlet rate of the water outlet pipe is stable, it is connected to the liquid inlet 21 at the bottom of the expansion test cylinder 11, and the viscous sliding belt soil expansion force test experiment is started. The water flows into the test soil sample 19 from the circular holes of the lower honeycomb pad and the bottom permeable stone plate 18 in turn, and then the water flows out from the top permeable stone plate 18 and the circular holes of the upper honeycomb pad 17-3 and flows out from the liquid outlet 22. The water flowing out of the water outlet pipe is collected separately. By adjusting the set temperature of the injection device 25, the viscous sliding belt soil expansion force test under different water temperature environmental conditions can be realized, and by adjusting the water injection seepage rate, the viscous sliding belt soil expansion force test under different water pressure environmental conditions can be realized. The distilled water in the above-mentioned injection device 25 can be heated by setting a special heater, and the water temperature heating range is 20℃~50℃.

[0087] Step 5. Relevant data parameters are collected and saved by the data acquisition system 26. The slit viewport 13 on the left can use a camera to record the water level rise in real time. The water gravity generated by the water flowing through the upper honeycomb pad, the lower honeycomb pad and the permeable stone slab 18 is monitored by the pressure sensor 23 on the experimental table 2. The annular expansion force of the viscous sliding zone soil is monitored by the annular expansion force sensor in the mounting hole 14-2 on the right. The corresponding soil sample temperature is also monitored in real time by the temperature sensor in the mounting hole 14-2 on the right. The axial expansion force generated after the soil sample reaches the saturated state is recorded and monitored by the upper axial expansion force sensor until the expansion force data detected by the axial expansion force sensor changes by less than 0.1 kPa within 2 hours, which is considered stable.

[0088] Step 6. After successfully completing step 5, loosen the lifting rod fixing bolt 8, so that the axial expansion force generated by the test soil sample 19 drives the top permeable stone plate 18, upper honeycomb pad 17-3, upper piston rod 17-2, mounting disc 10, lifting rod 9 and other components to move upward, so that the test soil sample 19 can expand freely under the lateral limit conditions, and record the monitoring data of various attribute objects in real time until all expansion force data change within 2 hours. The amplitude is less than 0.1kPa, which is considered stable.

[0089] Step 7. After successfully completing step 6, turn off the switch of the liquid injection device 25 and unplug the water outlet pipe on the liquid injection device 25. The water flowing out of the liquid inlet 21 at the bottom of the expansion test cylinder 11 is drained and collected separately by a rubber tube. The lifting rod 9 is in an active state, and the data acquisition system 26 monitors the expansion force related data in real time. After all the water in the test soil sample 19 has flowed out, the expansion force data is considered stable when the change range is less than 0.1 kPa within 2 hours.

[0090] It can be seen that the present technical scheme specifically relates to a device and method for testing the swelling force of viscous sliding zone soil formed by sliding along the soft layer of a slope controlled by a coal-bearing stratum, a bauxite stratum, and a soft stratum dominated by expansive minerals. The device and method include an instrument test bench, a volume adjustment and expansion device, an expansion test cylinder, a sensor device assembly, a data acquisition system, and a liquid injection device. The instrument test bench provides test environment conditions. The expansion test cylinder is installed on the laboratory table of the instrument test bench. The upper honeycomb pad cooperates with the lifting rod to achieve the sample preparation goal. The sensor device assembly is respectively located on the mounting disc and the laboratory table of the instrument test bench. After the liquid injection device injects water from the liquid inlet at the bottom of the expansion test cylinder, the axial expansion force, annular expansion force and temperature monitored by the sensor device assembly are recorded and stored in real time by the data acquisition system. Compared with the prior art, this technical solution can realize the expansion force test of viscous sliding zone soil under different physical property state conditions and environmental state conditions, including axial expansion force and circumferential expansion force. The pressure sensor, temperature sensor and micrometer are used to record the test data in real time and the data acquisition system records and stores it. This is an expansion force tester with higher test accuracy, simpler test conditions, and more test property objects. Compared with the prior art, the specific beneficial effects of this technical solution are as follows:

[0091] (1) The present technical solution is provided with a volume adjustment and expansion device, which has a lifting rod structure, and the lifting rod and its mounting disc are connected in a detachable manner. The lifting rod and the mounting disc can be detached from each other, which can provide a compaction function for the viscous sliding belt soil test sample to reach a predetermined dry density, and the water level rise height slit viewport on the side of the auxiliary expansion test cylinder can be used to observe the compaction thickness. At the same time, the separation design function also makes the test process and steps of the present test device simpler; the present technical solution can also simultaneously realize the expansion force test of the viscous sliding belt soil under constant volume conditions and free expansion conditions, and the expansion force test under different volume conditions can be controlled by adjusting the lifting rod fixing bolts.

[0092] (2) This testing device can realize the expansion force test of viscous sliding zone soil under different physical property conditions. It can change the clay mineral component ratio, compaction size, initial moisture content and dry density of the test soil sample. It uses axial expansion force sensor, circumferential expansion force sensor, temperature sensor and micrometer to collect test data in real time. It has a high degree of automation and has changed the previous testing technology that could not realize the testing requirements of different physical property conditions.

[0093] (3) The test device can also realize the expansion force test of viscous sliding zone soil under different environmental conditions. The water flow velocity can be changed to change the injection pressure, and the water flow temperature can be changed to change the ambient temperature. The functionality of the test device has been significantly improved, and more test attribute objects have been added.

[0094] (4) This test device can observe the hysteresis effect of the annular expansion force of the viscous sliding zone soil after water injection and seepage. The water level rise height can be observed through the slit viewport, and the hysteresis effect between the annular expansion force and stable change experimental data can be compared in real time. This is impossible to achieve in previous technologies.

[0095] (5) This test device can realize the expansion force test of viscous sliding belt soil under drainage conditions. In the process of completing the expansion test of a test soil sample, in order to obtain as much test property experimental data as possible, the drainage condition test can be realized by adjusting the injection device, that is, by pulling out the water outlet pipe.

[0096] It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any figure mark in the claims should not be regarded as limiting the claims involved.

[0097] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A device for testing the swelling force of viscous sliding zone soil, characterized in that: include: A test bench, wherein an expansion test cylinder is arranged on the test bench, a liquid inlet is arranged at the bottom of the expansion test cylinder, and a liquid outlet is arranged at the top; the test bench comprises a load-bearing platform, a laboratory table and a leveling support rod, the laboratory table is arranged on the upper surface of the load-bearing platform, the leveling support rod is arranged on the upper surface of the laboratory table, and a plurality of leveling support rods are evenly arranged, the bottom ends of all the leveling support rods are threadedly connected to the laboratory table, the expansion test cylinder is arranged above the leveling support rod, and is connected to the top ends of all the leveling support rods; A top plate, the top plate is supported on the experimental table by a support rod, and the top plate is located above the expansion test cylinder; A volume regulating and expansion device, the volume regulating and expansion device comprises a driving mechanism, an upper piston assembly and a lower piston assembly, the upper piston assembly comprises an upper honeycomb pad and an upper piston rod, the upper honeycomb pad is arranged at the upper part of the cylinder cavity of the expansion test cylinder, and the upper piston rod is connected to the upper surface of the upper honeycomb pad; the lower piston assembly comprises a lower honeycomb pad and a lower piston rod, the lower honeycomb pad is arranged at the lower part of the cylinder cavity of the expansion test cylinder, and the lower piston rod is connected to the lower surface of the lower honeycomb pad, a sample space for accommodating a test soil sample is formed between the upper honeycomb pad, the lower honeycomb pad and the cylinder wall of the expansion test cylinder, at least one of the upper piston rod and the lower piston rod is connected to the driving mechanism, and the driving mechanism can make the upper honeycomb pad and the lower honeycomb pad approach or move away from each other to adjust the volume of the sample space; Permeable stone plates are arranged between the test soil sample and the upper honeycomb pad, and between the test soil sample and the lower honeycomb pad, so as to intercept the test soil sample in the sample space during the test; wherein, the lower piston rod is arranged to penetrate the bottom of the expansion test cylinder, and the lower piston rod and the expansion test cylinder are sealed by a pan seal, and the pan seal is fixed to the bottom of the expansion test cylinder by a fixing cap; the driving mechanism includes a hollow straight cylinder, a lifting rod, a mounting disc and a lifting rod fixing bolt, the hollow straight cylinder is arranged on the upper surface of the top plate, the The lifting rod is slidably sleeved in the hollow straight cylinder, and the bottom end of the lifting rod passes through the top plate, and the top end of the lifting rod is used to connect the lifting power source; the upper surface of the mounting disc is detachably connected to the bottom end of the lifting rod, the top end of the upper piston rod is connected to a tray, and the lower surface of the mounting disc is detachably connected to the tray; the lifting rod fixing bolt passes through the side wall of the hollow straight cylinder, and the lifting rod fixing bolt is threadedly connected to the side wall of the hollow straight cylinder, and the tail of the lifting rod fixing bolt can extend into the hollow straight cylinder and tighten the lifting rod; A liquid injection device, the liquid injection device is connected to the liquid inlet and is used to inject a test liquid into the expansion test cylinder, and the temperature and injection flow rate of the test liquid are adjustable; A sensing device assembly, the sensing device assembly comprising an axial expansion force detection device, a circumferential expansion force detection device and a temperature detection device, the circumferential expansion force detection device and the temperature detection device being arranged on the expansion test cylinder; the axial expansion force detection device can detect the expansion force exerted on the upper piston assembly and the lower piston assembly; wherein the bottom end of the lower piston rod is connected to the experimental table through the axial expansion force detection device, and the top end of the lower piston rod is connected to the lower honeycomb pad; the top end of the upper piston rod is connected to the driving mechanism through the axial expansion force detection device, and the axial expansion force detection device is arranged on the mounting disc, and can detect the expansion force exerted on the upper piston assembly; A data acquisition system is communicatively connected with the liquid injection device, the driving mechanism, the axial expansion force detection device, the annular expansion force detection device and the temperature detection device.

2. The device for testing the swelling force of viscous sliding zone soil according to claim 1, characterized in that: The side wall of the expansion test cylinder is provided with a slit viewport extending along its axial direction, and the slit viewport is connected with the cylinder cavity of the expansion test cylinder; a transparent glass plate is sealed in the slit viewport to observe the change of the liquid level in the expansion test cylinder; and a liquid level scale is also provided on the outer side of the slit viewport.

3. The device for testing the swelling force of viscous sliding zone soil according to claim 2, characterized in that: The sensor device assembly also includes an image acquisition device, a micrometer and a spirit level, and the image acquisition device, the micrometer and the spirit level are all communicatively connected to the data acquisition system, wherein the image acquisition device is used to record the height of the liquid level rise through the slit viewport in real time, the micrometer is arranged on the support rod, and the mounting disc and the top of the expansion test cylinder are both provided with the spirit level.

4. The device for testing the swelling force of viscous sliding zone soil according to claim 2, characterized in that: A plurality of mounting holes are provided on the side wall of the expansion test cylinder opposite to the slit viewport, and all of the mounting holes are distributed along the axial direction of the expansion test cylinder; any one of the mounting holes is connected to the cylinder cavity of the expansion test cylinder, the inner ends of some of the mounting holes are installed with the annular expansion force detection device, and the inner ends of the remaining mounting holes are installed with the temperature detection device; the outer ends of any one of the mounting holes are threadedly connected with a hollow screw to seal the mounting hole; wherein the hollow screw is formed by connecting two semi-hollow screws, and the data cable of the annular expansion force detection device or the temperature detection device is embedded in the inner cavity of the hollow screw.

5. The device for testing the swelling force of viscous sliding zone soil according to claim 1, characterized in that: The outer circumferences of the upper honeycomb pad and the lower honeycomb pad are both provided with grooves, in which a plurality of steel balls are embedded. The outer circumferences of the upper honeycomb pad and the lower honeycomb pad are slidably matched with the inner cylinder wall of the expansion test cylinder through the steel balls.

6. A method for testing the swelling force of viscous sliding zone soil using the swelling force testing device of viscous sliding zone soil according to claim 1, characterized in that: include: Step 1, laying the permeable stone slab on the upper honeycomb pad, placing a test soil sample of target dry density mass into the expansion test cylinder, removing the mounting disc, and driving the lifting rod to descend to compact the test soil sample to form a block test soil sample; Step 2, placing the permeable stone plate and the upper honeycomb pad connected with the upper piston rod and the tray in sequence above the block test soil sample, installing the mounting disc and driving the lifting rod to descend until the mounting disc is connected with the tray, and fixing the position of the lifting rod; Step 3, clearing the axial expansion force detection device, the circumferential expansion force detection device and the temperature detection device; Step 4, injecting a test liquid into the expansion test cylinder to start a viscous sliding zone soil expansion force test experiment; Step 5: Collect and save the data of the sensor device assembly through the data acquisition system; Step 6, loosen the lifting rod, so that the axial expansion force generated by the block test soil sample drives the upper honeycomb pad to move upward, and at the same time, the axial expansion force, annular expansion force and temperature of the block test soil sample after liquid absorption are recorded in real time through the sensor device assembly; Step 7: Discharge the test liquid in the expansion test cylinder through the liquid inlet.

7. The method for testing the swelling force of viscous sliding zone soil according to claim 6, characterized in that: In step 1, the step of pressing the block test soil sample comprises: Step 11, placing a test soil sample of target dry density mass into the expansion test cylinder, and driving the lifting rod to descend to compact the test soil sample to form a first layer of block test soil sample; Step 12: Place a test soil sample with the same target dry density mass on top of the first layer of block test soil samples, and drive the lifting rod to descend to compact the test soil sample again to form the block test soil sample.

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