Soil coupling test device and test method for researching full-scale strength of soil

Abstract

The invention provides a soil body coupling test device and a test method for researching the full-scale strength of a soil body, the soil body coupling test device comprises a soil body testing machine, a track, a box body and an environment simulation assembly, the soil body testing machine comprises a test bed and a loading assembly, the device is used for carrying out one or more of a tensile test, a compression-shear test and a tension-shear test on a soil body sample, so that the physical properties of the soil body are tested. The box body is movably arranged on the track, the box body is provided with a test cavity used for accommodating a soil body sample and at least partially accommodating the loading assembly, and the sample cavity is adjusted to proper temperature and humidity through the environment simulation assembly, so that physical characteristics and mechanical laws of the soil body sample in different environments such as high temperature, heavy fog and rainy days can be simulated; and engineering practice can be better guided.

Description

Technical Field

[0001] The invention belongs to the technical field of soil coupling test, and in particular relates to a soil coupling test device and a test method for studying the full-scale strength of soil. Background Art

[0002] The damage of engineering soil is not only related to the change of groundwater level, the increase of external load, earthquake and other factors, but also closely related to the environmental conditions in which it is located. For example, in hot weather, due to the high ambient temperature and low relative humidity of the air, the water in the soil will evaporate, resulting in a decrease in water content. In cold weather, the water in the soil will freeze and expand. In foggy and rainy weather, the relative humidity of the air is high. As the temperature drops, the water in the air will liquefy into water droplets and enter the soil, increasing the water content of the soil. Under different environmental conditions, the properties of the soil will change, and its corresponding mechanical properties will also be different.

[0003] In the prior art, the tensile and shear coupling tests on soil are all conducted in laboratory environments, which are different from the actual environment in which the soil is located. The results of soil coupling tests conducted in laboratory environments will also deviate from the actual environment. Therefore, studying the impact of different environmental conditions on the mechanical properties of soil is crucial to guiding engineering practice and improving engineering quality. Summary of the invention

[0004] The present invention provides a soil coupling test device and a test method for studying the full-scale strength of soil, aiming to solve the problem that the soil coupling test in the prior art is all carried out in a laboratory environment and the test results deviate from the actual situation.

[0005] To achieve the above object, the technical solution adopted by the present invention is: In a first aspect, the present invention provides a soil coupling test device, comprising: A soil testing machine, comprising a test bench and a loading assembly arranged on the test bench; A track is arranged on one side of the soil testing machine in a horizontal direction; a box body, slidably arranged on the track, the box body having a test cavity, the test cavity having an entrance and an exit on a side facing the soil testing machine, the entrance and an exit being movably connected with a box door; the box body having a test position and an idle position, when in the test position, the loading assembly is at least partially accommodated in the test cavity, and when in the idle position, the loading assembly is separated from the test cavity; and The environmental simulation component includes a temperature control module and a humidity control module, wherein the temperature control module and the humidity control module are respectively arranged in the box body, the temperature control module is used to adjust the temperature of the test chamber, and the humidity control module is used to adjust the humidity of the test chamber.

[0006] In a possible implementation, a heat exchange hole is opened on a side wall of the test chamber, the heat exchange hole is connected to an air duct, and the output end of the temperature control module and the output end of the humidity control module are respectively connected to the air duct.

[0007] In a possible implementation, the soil coupling test device also includes a reaction force frame, which is arranged on the test bench and is used to enclose a test area with the table top of the test bench, and the test area is functionally divided into a tensile shear zone, a stretching zone and a compressive shear zone; the loading assembly includes a first shear test mechanism arranged in the tensile shear zone, a stretching test mechanism arranged in the stretching zone, and a second shear test mechanism arranged in the compressive shear zone.

[0008] In a possible implementation, the reaction force framework includes: A top plate, disposed above the test bench; and Two side panels are arranged opposite to each other, and the side panels are connected between the top panel and the test bench. The top panel, the side panels and the upper surface of the test bench together enclose the test area. The tensile shear zone is arranged adjacent to one of the side panels, and the compressive shear zone is arranged adjacent to the other side panels.

[0009] In a possible implementation, the first shear test mechanism includes: A first slide rail is horizontally arranged on the test bench and located in the corresponding tensile shearing area; a first soil-making device, slidably engaged with the first slide rail; A first shear force loading unit is provided on the reaction force frame and has a first telescopic end that can be telescoped along the length direction of the first slide rail, and the first telescopic end is provided with a first shear block; and The first shearing top block is arranged on the test bench. The first shearing top block and the first shearing block are arranged on both sides of the first soil-making device opposite to each other and are offset from each other in the up-down direction.

[0010] In a possible implementation, the first shear test mechanism, the tensile test mechanism, and the second shear test mechanism are arranged in a straight line direction, the reaction force frame is provided with an adjustment groove above the first shear test mechanism, the tensile test mechanism, and the second shear test mechanism, the loading assembly also includes a tension-compression loading mechanism slidably arranged in the adjustment groove, and the tension-compression loading mechanism has a lifting end capable of vertical movement.

[0011] In a possible implementation, the first soil-making device includes: A first connecting block, slidably matched with the first slide rail; A first restraining cylinder is disposed above the first connecting block and is detachably connected to the first connecting block; A second constraint cylinder is disposed above the first constraint cylinder and is detachably connected to the first constraint cylinder; and The second connecting block is arranged above the second constraint cylinder and is detachably connected to the second constraint cylinder. The upper part of the second connecting block is detachably connected to the lifting end. The first connecting block, the first constraint cylinder, the second constraint cylinder and the second connecting block together constitute a forming cavity of the soil sample. The radial cross-section of the forming cavity is circular, and the radial cross-section diameter of the forming cavity gradually shrinks from both ends to the middle.

[0012] In a possible implementation, a temperature monitoring element and a humidity monitoring element are provided on one side of the molding cavity formed by the first connecting block and / or on one side of the molding cavity formed by the second connecting block, wherein the temperature monitoring element is used to monitor the temperature of the soil sample, and the humidity monitoring element is used to monitor the humidity of the soil sample.

[0013] Compared with the prior art, the soil coupling test device provided by the present invention has the following beneficial effects: The soil coupling test device provided by the present invention comprises a soil testing machine, a track, a box and an environmental simulation component, wherein the soil testing machine comprises a test bench and a loading component, and is used to perform one or more of a tensile test, a compression shear test and a tension shear test on a soil sample, so as to test the performance of the soil. The box is movably arranged on the track, and the box has a test cavity for accommodating a soil sample and at least partially accommodating the loading component. The sample cavity is adjusted to a suitable temperature and humidity through the environmental simulation component, and the physical characteristics and mechanical laws of the soil sample in different environments such as high temperature, heavy fog and rainy days can be simulated, so as to better guide engineering practice.

[0014] The box in the present invention is designed to be movable and will only be moved to the test position when the test is carried out. Before the test, the soil sample can be placed in the test chamber to gradually reach the required temperature and humidity, and then the box is moved to the test position, and the soil sample is installed on the loading assembly for testing. Such a setting helps to reduce the time the loading assembly stays in the test chamber, thereby preventing the components on the loading assembly from being damaged by the temperature or humidity of the test chamber, and can increase the service life of the loading assembly.

[0015] The temperature control module in the present invention can adjust the temperature in the test chamber. After the test, the test chamber can be refrigerated by the temperature control module to freeze the soil sample and preserve its damaged state. CT scanning, SEM scanning, XRD analysis, transmission electron microscopy and the like can be used to further study the microscopic deformation and microstructure of the soil, thus facilitating the development of subsequent research.

[0016] In a second aspect, the present invention provides a test method for studying the full-scale strength of soil, using the soil coupling test device described in any of the above implementations, comprising the following steps: Determine the temperature and humidity required for the test; Fix the prepared soil sample on the loading assembly, push the box to move the box from the idle position to the test position, and place the soil sample in the test cavity; Close the box door and set the temperature parameters of the temperature control module and the humidity parameters of the humidity control module according to the temperature and humidity requirements; Wait until the temperature and humidity of the soil sample tend to be stable, control the loading component to perform a soil coupling test on the soil sample, and save images and data of the test results; After the test, the temperature control module is adjusted to the cooling state to freeze the soil sample and preserve its damaged state.

[0017] In a possible implementation, a plurality of soil samples are provided, and the loading assembly is used to perform tensile tests, tensile shear tests and compressive shear tests on the plurality of soil samples respectively. After the tests are completed, the strength envelope of the soil samples is drawn according to the test results.

[0018] The test method for studying the full-scale strength of soil provided by the present invention is implemented by the soil coupling test device described in any of the above-mentioned implementation methods, and has the same technical effect as the above-mentioned implementation methods, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the structure of a soil coupling test device provided in one embodiment of the present invention; Figure 2 for Figure 1 A partial enlarged view of the middle A part; Figure 3 It is a structural schematic diagram of a soil testing machine in another embodiment of the present invention; Figure 4 It is a schematic structural diagram of a first soil-making device in another embodiment of the present invention; Figure 5 It is a schematic structural diagram of a second soil-making device in another embodiment of the present invention; Figure 6 The strength envelope of soil drawn by using the test method provided by the present invention for studying the full-scale strength of soil; Description of reference numerals: 1. Soil testing machine; 2. Track; 3. Box; 4. Box door; 10. Test bench; 20. Loading assembly; 21. First shear test mechanism; 211. First slide rail; 212. First soil making device; 2121. First connecting block; 2122. First constraint cylinder; 2123. Second constraint cylinder; 2124. Second connecting block; 2125. Temperature monitoring element; 2126. Humidity monitoring element; 213. First shear loading unit; 214. First shear top Block; 22, tensile test mechanism; 23, second shear test mechanism; 231, second slide rail; 232, second soil making device; 2321, third connecting block; 2322, fourth connecting block; 2323, third constraint cylinder; 2324, fourth constraint cylinder; 2325, fifth constraint cylinder; 233, second shear loading unit; 234, second shear top block; 24, tension and compression loading mechanism; 30, reaction frame; 31, top plate; 32, side plate; 40, soil sample. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] Please also read Figures 1 to 5 , the soil coupling test device provided in an embodiment of the present invention and the test method for studying the full-scale strength of soil are described below.

[0022] See also Figure 1 In the first aspect, an embodiment of the present invention provides a soil coupling test device, including a soil testing machine 1, a track 2, a box 3 and an environmental simulation component. The soil testing machine 1 includes a test bench 10, and a loading component 20 arranged on the test bench 10; the track 2 is arranged on one side of the soil testing machine 1 in the horizontal direction; the box 3 is slidably arranged on the track 2, and the box 3 has a test chamber, and the test chamber is provided with an inlet and an outlet on the side facing the soil testing machine 1, and a box door 4 is movably connected at the inlet and outlet; the box 3 has a test position and an idle position, when in the test position, the loading component 20 is accommodated in the test chamber, and when in the idle position, the loading component 20 is separated from the test chamber; the environmental simulation component includes a temperature control module and a humidity control module, and the temperature control module and the humidity control module are respectively arranged in the box 3, the temperature control module is used to adjust the temperature of the test chamber, and the humidity control module is used to adjust the humidity of the test chamber.

[0023] Compared with the prior art, the soil coupling test device provided by the embodiment of the present invention has the following beneficial effects: The soil coupling test device provided by the embodiment of the present invention includes a soil testing machine 1, a track 2, a box 3 and an environmental simulation component, wherein the soil testing machine 1 includes a test bench 10 and a loading component 20, which are used to perform one or more of a tensile test, a compression shear test and a tension shear test on a soil sample 40, so as to test the physical properties of the soil. The box 3 is movably arranged on the track 2, and the box 3 has a test cavity for accommodating the soil sample 40 and at least partially accommodating the loading component 20. The sample cavity is adjusted to a suitable temperature and humidity through the environmental simulation component, and the physical characteristics and mechanical laws of the soil sample 40 in different environments such as high temperature, foggy days and rainy days can be simulated, so as to better guide engineering practice and improve engineering quality.

[0024] The box 3 in the embodiment of the present invention adopts a movable design and is moved to the test position only when the test is carried out. Before the test, the soil sample 40 can be placed in the test chamber to gradually reach the required temperature and humidity, and then the box 3 is moved to the test position, and the soil sample 40 is installed on the loading assembly 20 for testing. Such a setting helps to reduce the time that the loading assembly 20 stays in the test chamber, thereby preventing the components (such as force sensors, fixtures, etc.) on the loading assembly 20 from being damaged by the temperature or humidity of the test chamber, and can increase the service life of the loading assembly 20.

[0025] The temperature control module in the embodiment of the present invention can adjust the temperature in the test chamber. After the test, the test chamber can be cooled by the temperature control module to freeze the soil sample 40 and preserve its damaged state. CT scanning, SEM scanning, XRD analysis, transmission electron microscopy, etc. can be used to further study the microscopic deformation and microstructure of the soil, which facilitates the development of subsequent research.

[0026] The soil testing machine 1 is a multifunctional soil testing device. According to the needs, different models and specifications of testing devices can be selected to perform test operations such as tensile test, tensile shear test and compression shear test on the soil sample 40. The soil testing machine 1 includes a test bench 10 and a loading assembly 20. The loading assembly 20 is arranged on the test bench 10. The loading assembly 20 can specifically include a tensile loading mechanism, a compression shear loading mechanism and a tensile shear loading mechanism.

[0027] The track 2 is arranged on one side of the test bench 10, and the track 2 is arranged horizontally. The track 2 can be a circular, square or other shaped guide rail, as long as the box 3 can move smoothly. The box 3 is movably arranged on the track 2, and the box 3 can be driven manually or by a driving member such as a hydraulic push rod. The box 3 has a test cavity for accommodating the soil sample 40 and the loading assembly 20. When the loading assembly 20 is as shown in FIG. Figure 1When only a portion of the loading assembly 20 is contained in the test cavity, a side wall of the test cavity should be provided with an avoidance hole or avoidance groove for the corresponding portion of the loading assembly 20 to pass through.

[0028] The box door 4 is movably arranged at the entrance and exit, and the box door 4 can be installed and fixed on the box body 3 by screw connection, plug connection, hinge rotation connection, etc. In order to facilitate the operator to observe the internal situation, an observation window can be set on the box door 4, and a transparent glass plate is provided on the observation window.

[0029] It is understandable that before the test, the soil sample 40 needs to be placed in the test chamber for a period of time so that the temperature, humidity and other parameters of the soil sample 40 meet the environmental simulation requirements. Optionally, the soil sample 40 can be first installed on the loading assembly 20, and then the box 3 is moved to the test position. At this time, the soil sample 40 and the loading assembly 20 are both in the temperature and humidity environment simulated by the test chamber. Alternatively, the soil sample 40 can also be placed in the test chamber first, and after the temperature and humidity of the soil sample 40 meet the requirements, the box 3 is moved to the test position, and the soil sample 40 is installed on the loading assembly 20 to conduct a coupling test. In this way, the loading assembly 20 stays in the test chamber for a shorter time, and the related components are not easily affected by factors such as temperature and humidity.

[0030] The environmental simulation component includes a temperature control module and a humidity control module. The temperature control module specifically includes a refrigeration unit and a heating unit. The humidity control module includes a humidifier. The refrigeration unit can use a compressor for refrigeration, and the heating unit can be a heat pump or an electric heater. The air flow can be achieved by setting a circulating fan and inlet and outlet holes in the test chamber to make the temperature and humidity in the test chamber uniform. The humidifier is equipped with a water tank and a water level display. When the humidifier is short of water, the operator should add water to the water tank in time.

[0031] The environmental simulation component can be controlled through the LCD touch screen. The humidity adjustment range can be specifically 15-95%RH, and the temperature adjustment range can be specifically -30℃-60℃.

[0032] See also Figure 1 In some possible embodiments, the box body 3 also includes an equipment accommodating cavity, the temperature control module and the humidity control module are respectively arranged in the equipment accommodating cavity, a heat exchange hole is opened on the side wall of the test cavity, the heat exchange hole is connected to an air duct, the air inlet end of the air duct is arranged in the equipment accommodating cavity, the output end of the temperature control module and the output end of the humidity control module are respectively connected to the air duct, a circulating fan is arranged in the air duct, and after the airflow is mixed in the air duct, it enters the test cavity through the heat exchange hole.

[0033] See also Figure 1 and Figure 3In some possible embodiments, the soil coupling test device also includes a reaction frame 30, which is arranged on the test bench 10 and is used to enclose a test area with the table top of the test bench 10. The test area is functionally divided into a tensile shear area, a stretching area and a compressive shear area; the loading assembly 20 includes a first shear test mechanism 21 arranged in the tensile shear area, a stretching test mechanism 22 arranged in the stretching area, and a second shear test mechanism 23 arranged in the compressive shear area.

[0034] In this embodiment, the test area is divided into a tensile shear area, a stretching area and a compression shear area according to their functions, which are used to perform tensile shear tests, tensile tests and compression shear tests on the soil sample 40, respectively, so as to realize the mechanical property experiments of uniaxial tension, tension-shear and compression-shear on the soil sample 40. Among them, when the soil sample 40 is subjected to uniaxial tension and tension-shear, the shape of the soil sample 40 is thick at both ends and thin in the middle, and its radial cross section is circular, and the middle section is cylindrical. The overall height dimension of the soil sample 40 is 120mm, and the middle cylindrical section is 20mm high and 39mm in diameter. Since the soil sample 40 is not subjected to tension during the compression-shear test, the soil sample during compression-shear can be designed to be the same size as the above-mentioned middle cylindrical section, that is, a cylindrical shape with a height of 20mm and a diameter of 39mm.

[0035] The above three tests of tension, tension-shear and compression-shear can be carried out simultaneously or sequentially. Since the middle section of the soil sample 40 used in the above three tests has the same shape and size, the loading assembly 20 can be implemented as follows: Figure 6 The experimental measurement of the complete strength envelope of the soil shown provides a theoretical basis for engineering practice. The loading assembly 20 can be driven by a servo motor controlled by a controller, which has high control accuracy, good stability, time saving and labor saving, and is equipped with data recording and data processing software, which can record and process data in real time.

[0036] It should be noted that when conducting tensile and tensile-shear tests, the shape of the soil sample 40 is thick at both ends and thin in the middle. The purpose is to allow the two ends of the soil sample 40 to be partially accommodated in the upper and lower clamps respectively. In this way, when stretching, the tensile state of the soil sample 40 can be truly simulated, thereby ensuring the accuracy of the test results.

[0037] See also Figure 1 and Figure 3In some possible embodiments, the reaction frame 30 includes a top plate 31 and two side plates 32. The top plate 31 is arranged above the test bench 10. The two side plates 32 are arranged opposite to each other. The side plates 32 are connected between the top plate 31 and the test bench 10. The top plate 31, the side plates 32 and the upper surface of the test bench 10 together enclose a test area. The shearing zone is arranged adjacent to one of the side plates 32, the compression shearing zone is arranged adjacent to the other side plates 32, and the stretching zone is arranged between the shearing zone and the compression shearing zone.

[0038] See also Figure 3 and Figure 4 In some possible embodiments, the first shear test mechanism 21 includes a first slide rail 211, a first soil making device 212, a first shear force loading unit 213 and a first shear top block 214. The first slide rail 211 is arranged on the test bench 10 in the horizontal direction and is located in the corresponding tensile shear area; the first soil making device 212 is used to make the soil sample 40, and the first soil making device 212 is slidably matched with the first slide rail 211; the first shear force loading unit 213 is arranged on the reaction frame 30, and has a first telescopic end that can be telescoped along the length direction of the first slide rail 211, and the first telescopic end is provided with a first shear block; the first shear top block 214 is arranged on the test bench 10, and the first shear top block 214 and the first shear block are arranged on both sides of the first soil making device 212 opposite to each other, and are offset from each other in the up and down directions.

[0039] In this embodiment, the first shear test mechanism 21 includes a first slide rail 211, a first soil making device 212, a first shear force loading unit 213 and a first shear top block 214. The first shear force loading unit 213 and the first shear top block 214 are arranged relative to the first soil making device 212 and can move along their respective length directions, thereby applying shear force to the soil sample 40. The movement of the first shear force loading unit 213 and the first shear top block 214 can be automatically controlled by power equipment such as a servo motor and a hydraulic cylinder, or can be manually adjusted by structures such as a screw rod and a hand wheel. A pressure sensor is provided between the first telescopic end and the first shear block to measure the pressure applied by the first shear block to the soil sample 40.

[0040] The first soil making device 212 is used to make a soil sample 40 of a specific shape. The lower end of the first soil making device 212 is slidably arranged on the first slide rail 211, and the upper end of the first soil making device 212 is used to connect with the tension and compression loading mechanism 24. The tension and compression loading mechanism 24 can be driven by a servo motor or a hydraulic cylinder, etc., and contains a displacement sensor and a tension sensor, which are used to apply a moving tension or pressure to the soil sample 40.

[0041] It should be noted that the first soil making device 212 has a soil making state and a test state. When in the soil making state, it can form a closed forming cavity by itself, which is used to form a soil sample 40 of a specific shape. When a test is required, the arc plate or sleeve and other parts of the first soil making device 212 used to enclose and form the forming cavity can be removed as needed, so that the first soil making device 212 is in the test state. When the test is carried out, a shear ring is added to the periphery of the soil sample 40, and the first shear force loading unit 213 applies shear force to the soil sample 40 through shearing. Of course, when the arc plate does not affect the normal test, it can also be left intact, and the operator can choose according to the actual situation.

[0042] See also Figure 3 In some possible embodiments, the first shear test mechanism 21, the tensile test mechanism 22, and the second shear test mechanism 23 are arranged in a straight line direction, the reaction frame 30 is provided with an adjustment groove above the first shear test mechanism 21, the tensile test mechanism 22, and the second shear test mechanism 23, and the loading assembly 20 also includes a tension-compression loading mechanism 24 slidably arranged in the adjustment groove, and the tension-compression loading mechanism 24 has a lifting end that can move vertically.

[0043] In this embodiment, the tension and compression loading mechanism 24 can move along the adjustment groove, thereby switching between the tension shear zone, the stretching zone and the compression shear zone, and can perform tension shear test, tension test and compression shear test respectively. On the one hand, it simplifies the device structure and saves the manufacturing cost of the device. On the other hand, using the same tension and compression loading mechanism 24 to perform three tests can eliminate the test errors caused by different instruments, which helps to improve the test precision and the accuracy of the results.

[0044] See also Figure 3 and Figure 4 In some possible embodiments, the first soil making device 212 includes a first connection block 2121, a first constraint cylinder 2122, a second constraint cylinder 2123 and a second connection block 2124. The first connection block 2121 is slidably matched with the first slide rail 211; the first constraint cylinder 2122 is arranged above the first connection block 2121 and is detachably connected to the first connection block 2121; the second constraint cylinder 2123 is arranged above the first constraint cylinder 2122 and is detachably connected to the first constraint cylinder 2122; the second connection block 2124 is arranged above the second constraint cylinder 2123 and is detachably connected to the second constraint cylinder 2123, and the upper part of the second connection block 2124 is detachably connected to the lifting end of the tension and compression loading mechanism 24, and the first connection block 2121, the first constraint cylinder 2122, the second constraint cylinder 2123 and the second connection block 2124 together constitute a forming cavity of the soil sample 40, and the radial cross section of the forming cavity is circular, and the radial cross section diameter of the forming cavity gradually shrinks from both ends to the middle.

[0045] In this embodiment, the first soil making device 212 can also be used to make a soil sample 40 for a tensile test. The tension and compression loading mechanism 24 is used to be connected to the top of the first soil making device 212 (i.e., the second connecting block 2124), and can apply a certain tensile force thereto to perform a tensile test or a tensile shear test.

[0046] In this embodiment, the first connection block 2121 and the first constraint cylinder 2122, and the second constraint cylinder 2123 and the second connection block 2124 can be connected by threads. The first constraint cylinder 2122 and the second constraint cylinder 2123 are arranged opposite to each other, and a detachable connection is achieved by screws between the mating surfaces of each other. During the test, the screws between the first constraint cylinder 2122 and the second constraint cylinder 2123 are removed. The first constraint cylinder 2122 and the second constraint cylinder 2123 can be an integrated cylinder, or an assembly formed by a plurality of arc plates, and adjacent arc plates can be detachably connected by snap connection, screw connection, etc. When the soil sample 40 is manufactured and installed on the loading assembly 20, the first constraint cylinder 2122 and the second constraint cylinder 2123 can be removed, and then a shear ring can be added to the outer periphery of the soil sample 40. Of course, the first constraint cylinder 2122 and the second constraint cylinder 2123 can also be left intact without affecting the normal test.

[0047] like Figure 4 As shown, the first constraint cylinder 2122 and the second constraint cylinder 2123 have the same structure. The structure of the first constraint cylinder 2122 is described in detail below: Specifically, the first constraint cylinder 2122 includes a first molding inner cavity and a second molding inner cavity. The first molding inner cavity and the second molding inner cavity are connected to each other and axially penetrate the first constraint cylinder 2122. The first molding inner cavity is a conical inner cavity. The large diameter end of the first molding inner cavity is connected to the first connecting block 2121, and the small diameter end of the first molding inner cavity is connected to the second molding inner cavity. The second molding inner cavity is a cylindrical inner cavity with an inner diameter of 39 mm and a height of 10 mm.

[0048] When conducting a tensile-shear test, the soil sample 40 is fixed on the first slide rail 211 below, which can effectively reduce friction and make the first shear block and the first shear top block 214 close to the soil sample. The first connecting block 2121 is set on the slider, and the slider and the first slide rail 211 slide in cooperation, so that the slider and the soil sample 40 can move synchronously when sheared.

[0049] See also Figure 4 In some possible embodiments, a temperature monitoring element 2125 and a humidity monitoring element 2126 are provided on one side of the molding cavity formed by the first connecting block 2121 and / or on one side of the molding cavity formed by the second connecting block 2124. The temperature monitoring element 2125 is used to monitor the temperature of the soil sample 40, and the humidity monitoring element 2126 is used to monitor the humidity of the soil sample 40.

[0050] This embodiment installs a temperature monitoring element 2125 and a humidity monitoring element 2126 on at least one of the first connecting block 2121 or the second connecting block 2124, so as to monitor in real time whether the temperature and humidity of the soil sample 40 are consistent with the ambient temperature and humidity in the test chamber, and whether the temperature and humidity state of the soil sample 40 has remained stable. When the state of the soil sample 40 is stable, the corresponding coupling test can be carried out, which is more convenient to operate.

[0051] See also Figure 3 and Figure 5 In some possible embodiments, the structure and working principle of the second shear test mechanism 23 are similar to those of the first shear test mechanism 21. The second shear mechanism specifically includes a second slide rail 231, a second soil making device 232, a second shear force loading unit 233 and a second shear top block 234. The second shear force loading unit 233 and the second shear top block 234 are arranged relative to the soil sample 40. The second soil making device 232 is used to make the soil sample 40. The second soil making device 232 specifically includes a third connecting block 2321, a fourth connecting block 2322, a third constraint cylinder 2323, a fourth constraint cylinder 2324 and a fifth constraint cylinder 2325, which can form a cylindrical molding cavity to make the soil sample 40. The tension and compression loading mechanism 24 is used to connect to one of the third connecting block 2321 or the fourth connecting block 2322, and apply a certain pressure thereto to perform a compression shear test.

[0052] In the second aspect, an embodiment of the present invention also provides a test method for studying the full-scale strength of soil, which is implemented using the soil coupling test device provided by any of the above embodiments, and includes the following steps: determining the temperature and humidity required for the test; fixing the prepared soil sample 40 on the loading assembly 20, pushing the box 3, so that the box 3 moves from the idle position to the test position, so that the soil sample 40 is placed in the test chamber; closing the box door 4, setting the temperature parameters of the temperature control module and the humidity parameters of the humidity control module according to the temperature and humidity requirements; waiting until the temperature and humidity of the soil sample 40 tend to stabilize, controlling the loading assembly 20 to perform a soil coupling test on the soil sample 40, and saving images and data of the test results; after the test, adjusting the temperature control module to the cooling state, freezing the soil sample 40, and preserving its damaged state.

[0053] In some possible embodiments, there are multiple soil samples 40, and the loading assembly 20 is used to perform tensile tests, tensile shear tests and compressive shear tests on the multiple soil samples 40 respectively. After the tests are completed, the strength envelope of the soil samples 40 is drawn according to the test results.

[0054] The test method for studying the full-scale strength of soil provided by the embodiment of the present invention can complete the tensile shear test, tensile test and compression shear test of the soil sample 40. The uniaxial tensile and tensile-shear samples of the soil sample 40 are both thick at both ends and thin in the middle, with a size of 120 mm in height, and a cylindrical middle part with a height of 20 mm and a diameter of 39 mm. The compression-shear soil sample 40 is a cylindrical shape with a height of 20 mm and a diameter of 39 mm, which not only ensures that the tensile force is applied to the soil sample during uniaxial tension and tensile-shearing, and that the normal stress is better transferred to the shear surface during compression-shearing, but also ensures the uniformity of the size and shape of the soil sample near the failure surface, thereby accurately measuring the complete strength envelope of the soil.

[0055] The loading component 20 can be loaded using a servo motor with high loading accuracy. It can realize various test force application methods such as constant stress, constant displacement, constant deformation, and load maintenance. Certain cycle steps can be set according to needs, and impact-free conversion can be achieved between multiple control methods to achieve fully automatic closed-loop control.

[0056] The loading component 20 is controlled by a controller, which may have built-in measurement and control software that can measure and display test force and peak value, displacement, deformation and other signals in real time, and can realize real-time screen display of various experimental curves such as stress-strain and stress-displacement.

[0057] It can be understood that the various parts in the above-mentioned embodiments can be freely combined or deleted to form different combination embodiments. The specific contents of each combination embodiment will not be repeated here. After this description, it can be considered that the specification of the present invention has recorded various combination embodiments and can support different combination embodiments.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A soil coupling test device, characterized in that: include: A soil testing machine, comprising a test bench and a loading assembly arranged on the test bench; A track is arranged on one side of the soil testing machine in a horizontal direction; a box body, slidably arranged on the track, the box body having a test cavity, the test cavity having an entrance and an exit on a side facing the soil testing machine, the entrance and an exit being movably connected with a box door; the box body having a test position and an idle position, when in the test position, the loading assembly is at least partially accommodated in the test cavity, and when in the idle position, the loading assembly is separated from the test cavity; and The environmental simulation component includes a temperature control module and a humidity control module, wherein the temperature control module and the humidity control module are respectively arranged in the box body, the temperature control module is used to adjust the temperature of the test chamber, and the humidity control module is used to adjust the humidity of the test chamber.

2. The soil coupling test device according to claim 1, characterized in that: A heat exchange hole is opened on the side wall of the test chamber, and the heat exchange hole is connected to an air duct. The output end of the temperature control module and the output end of the humidity control module are respectively connected to the air duct.

3. The soil coupling test device according to claim 1, characterized in that: The soil coupling test device also includes a reaction force frame, which is arranged on the test bench and is used to enclose a test area with the table top of the test bench. The test area is functionally divided into a tensile shear area, a stretching area and a compressive shear area; the loading assembly includes a first shear test mechanism arranged in the tensile shear area, a stretching test mechanism arranged in the stretching area, and a second shear test mechanism arranged in the compressive shear area.

4. The soil coupling test device according to claim 3, characterized in that: The reaction frame comprises: A top plate, disposed above the test bench; and Two side panels are arranged opposite to each other, and the side panels are connected between the top panel and the test bench. The top panel, the side panels and the upper surface of the test bench together enclose the test area. The tensile shear zone is arranged adjacent to one of the side panels, and the compressive shear zone is arranged adjacent to the other side panels.

5. The soil coupling test device according to claim 3, characterized in that: The first shear test mechanism comprises: A first slide rail is horizontally arranged on the test bench and located in the corresponding tensile shearing area; a first soil-making device, slidably engaged with the first slide rail; A first shear force loading unit is provided on the reaction force frame and has a first telescopic end that can be telescoped along the length direction of the first slide rail, and the first telescopic end is provided with a first shear block; and The first shearing top block is arranged on the test bench. The first shearing top block and the first shearing block are arranged on both sides of the first soil-making device opposite to each other and are offset from each other in the up-down direction.

6. The soil coupling test device according to claim 5, characterized in that: The first shear test mechanism, the tensile test mechanism, and the second shear test mechanism are arranged in a straight line direction, the reaction force frame is provided with an adjustment slot above the first shear test mechanism, the tensile test mechanism, and the second shear test mechanism, the loading assembly also includes a tension-compression loading mechanism slidably arranged in the adjustment slot, and the tension-compression loading mechanism has a lifting end capable of vertical movement.

7. The soil coupling test device according to claim 6, characterized in that: The first soil-making device comprises: A first connecting block, slidably matched with the first slide rail; A first restraining cylinder is disposed above the first connecting block and is detachably connected to the first connecting block; A second constraint cylinder is disposed above the first constraint cylinder and is detachably connected to the first constraint cylinder; and The second connecting block is arranged above the second constraint cylinder and is detachably connected to the second constraint cylinder. The upper part of the second connecting block is detachably connected to the lifting end. The first connecting block, the first constraint cylinder, the second constraint cylinder and the second connecting block together constitute a forming cavity of the soil sample. The radial cross-section of the forming cavity is circular, and the radial cross-section diameter of the forming cavity gradually shrinks from both ends to the middle.

8. The soil coupling test device according to claim 7, characterized in that: A temperature monitoring element and a humidity monitoring element are provided on one side of the molding cavity formed by the first connecting block and / or on one side of the molding cavity formed by the second connecting block. The temperature monitoring element is used to monitor the temperature of the soil sample, and the humidity monitoring element is used to monitor the humidity of the soil sample.

9. A test method for studying the full-scale strength of soil, characterized in that: The soil coupling test device according to any one of claims 1 to 8 comprises the following steps: Determine the temperature and humidity required for the test; Fix the prepared soil sample on the loading assembly, push the box to move the box from the idle position to the test position, and place the soil sample in the test cavity; Close the box door and set the temperature parameters of the temperature control module and the humidity parameters of the humidity control module according to the temperature and humidity requirements; Wait until the temperature and humidity of the soil sample tend to be stable, control the loading component to perform a soil coupling test on the soil sample, and save images and data of the test results; After the test, the temperature control module is adjusted to the cooling state to freeze the soil sample and preserve its damaged state.

10. The test method for studying the full-scale strength of soil according to claim 9, characterized in that: A plurality of soil samples are provided, and the loading assembly is used to respectively carry out tensile test, tensile shear test and compressive shear test on the plurality of soil samples. After the test, the strength envelope of the soil sample is drawn according to the test results.

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