Triaxial test soil sample preparation device capable of simulating sedimentary stratification distribution and preparation method

Abstract

The invention provides a triaxial test soil sample preparation device capable of simulating sedimentary stratification distribution and a preparation method. The preparation device comprises a rack, a sample compaction cylinder, a stratification positioning assembly and a pressurization assembly, the sample compaction cylinder is provided with a through chamber for accommodating a sample; the bedding positioning assembly comprises a bedding thickness control rod, a first pressing die and a second pressing die. The first pressing die and the second pressing die are provided with extrusion faces matched with each other. The first pressing die and the second pressing die at least comprise a plurality of replaceable pressing dies with different inclination angles and are used for controlling different bedding angles; in the state that the sample bedding is pressed, the bedding thickness control rod and the pressurizing assembly are installed on the two sides of the cylinder body respectively and fixedly arranged with the rack, the first pressing die is fixedly installed at the tail end of the bedding thickness control rod, and the second pressing die is installed at the end, facing the pressurizing assembly, of the cylinder body. Or the second pressing die is fixedly installed at the movable end of the pressurizing assembly, and at least one of the first pressing die and the second pressing die can stretch into the cylinder body.

Description

Technical Field

[0001] The invention relates to the technical field of geotechnical testing, and in particular to a triaxial test soil sample preparation device and a preparation method capable of simulating sedimentary bedding distribution. Background Art

[0002] In the field of geotechnical engineering, anisotropic soil with sedimentary stratification is usually formed during the natural sedimentation process or artificial layered compaction process. Sedimentary stratification is a weak interface of the soil, with variable distribution thickness and different distribution angles, which affects the strength, deformation and permeability characteristics of the layered soil, and further affects the long-term stability of the foundation and slope. Therefore, it is particularly important to carry out strength tests on soils containing sedimentary stratification, and how to accurately prepare triaxial test specimens that can simulate the distribution of sedimentary stratification has always been a difficulty in this field.

[0003] However, the traditional triaxial sample preparation device can only prepare homogeneous isotropic samples, which cannot meet the needs of preparing samples with sedimentary stratification. Although the existing anisotropic soil sample preparation device can prepare triaxial test samples with different sedimentary directions, such principle equipment requires first preparing anisotropic sample blocks, then cutting triaxial test cylindrical samples, and finally cutting and trimming them into standard triaxial samples. The operation is cumbersome and cannot directly prepare triaxial test standard samples containing sedimentary stratification; at the same time, such equipment does not consider the contact problem of the sample contact surface, and cannot prepare samples with arbitrary stratification thickness distribution; and the previous triaxial test sample preparation device does not have the sample cutting function, and the sample needs to be manually cut into the triaxial test standard sample, which has a large disturbance to the sample.

[0004] In view of this, there is an urgent need to develop a triaxial test soil sample preparation device and method that can simulate the distribution of sedimentary bedding, which can accurately complete a series of complex operations such as sample bedding positioning, layer roughening, sample preparation, sample cutting and demolding, and quickly prepare triaxial test specimens that can simulate any soil layer deposition thickness and angle, greatly improving the preparation efficiency and product quality of bedding specimens, so as to meet the urgent needs of scientific research and engineering practice for strength test specimens of soil samples containing sedimentary bedding. Summary of the invention

[0005] In view of this, an embodiment of the present invention provides a triaxial test soil sample preparation device and preparation method that can simulate sedimentary bedding distribution, so as to eliminate or improve one or more defects existing in the prior art.

[0006] One aspect of the present invention provides a triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution, the preparation device comprising: a frame, a sample compacting cylinder, a bedding positioning assembly, and a pressurizing assembly; The sample compacting cylinder comprises a cylinder body, wherein the cylinder body has a cavity which is used to accommodate the sample and is arranged through the cylinder body; The bedding positioning assembly comprises a bedding thickness control rod, a first die and a second die, wherein the first die and the second die have extrusion surfaces that match each other, the extrusion surfaces of the two dies are used to directly contact with the sample to extrude the bedding structure, the extrusion surfaces of the two dies are parallel or non-parallel to each other, and the extrusion surfaces are set to be smooth or rough, flat or curved; the first die and the second die at least include a plurality of replaceable dies with different inclination angles for controlling different bedding angles; When the preparation device is pressing the sample stratification, the stratification thickness control rod and the pressure assembly are respectively installed on both sides of the barrel and fixed to the frame, the first die is fixedly installed at the end of the stratification thickness control rod, the second die is installed at one end of the barrel facing the pressure assembly, or the second die is fixedly installed at the movable end of the pressure assembly, and at least one of the first die and the second die can extend into the barrel.

[0007] In some embodiments of the present invention, the sample compacting cylinder is arranged in a vertical direction, the first compression mold includes a top compression head, the second compression mold includes a bottom compression head, and the first compression mold and the second compression mold each include a matching bedding angle control pad; Wherein, the upper end of the top pressure head has a threaded hole or a threaded column for threaded connection with the bottom end of the bedding thickness control rod; The lower end of the bottom pressure head has a cylindrical section, and the cylindrical section is used to connect with the lower end of the sample compacting cylinder; The lower end of the top pressure head and the upper end of the bottom pressure head both have a pad connection portion, and the pad connection portion includes a mounting inclined surface and a slot structure; The end of the bedding angle control pad facing the pad connection portion is provided with a pressure head connection portion, and the pressure head connection portion includes another inclined surface of the same shape as the installation inclined surface of the pressure head, and a trapezoidal guide rail protrusion matching the slot structure; The bottom pressure head and the top pressure head are designed as a common mounting seat of the bedding angle control pad with different inclination angles; The bedding angle control pad includes a plurality of replaceable modules with different inclination angles, all of which are designed as rigid beveled cone structures.

[0008] In some embodiments of the present invention, the frame is a frame structure, including a top crossbeam, a slider mechanism, support columns arranged on both sides, and a bottom base; the support columns arranged on both sides are fixedly arranged on the bottom base, and the top crossbeam is fixedly arranged on the two support columns; The middle part of the top cross beam has a through slot which is arranged to penetrate in the vertical direction. The slider mechanism is installed in the through slot. The slider mechanism is configured to be able to move horizontally along the extension direction of the through slot.

[0009] In some embodiments of the present invention, the bedding thickness control rod of the bedding positioning assembly has an external thread for threaded connection with a slider of the slider mechanism, so that the bedding thickness control rod is installed in the through slot through the slider mechanism; The slider mechanism also includes a locking member for locking the position of the slider mechanism and the layer thickness control rod; The bedding thickness control rod is also provided with a length scale distributed along its axial direction, which is used to determine the depth of the bedding thickness control rod below the slider in combination with the bottom reference surface of the slider, so as to adjust the bedding thickness of the sample; The bedding positioning assembly further includes a first operating member disposed on the top of the bedding thickness control rod, and used for controlling the rotation of the bedding thickness control rod; The first operating member or the bedding thickness control rod is provided with a first bedding orientation positioning mark for indicating the inclination orientation of the extrusion surface of the first die; the bottom of the barrel is provided with a second bedding orientation positioning mark for indicating the inclination orientation of the extrusion surface of the second die.

[0010] In some embodiments of the present invention, the preparation device further comprises a layer roughening assembly, and the layer roughening assembly comprises a second operating member, a rotating plate, an angle adjuster, a transmission arm, a telescopic rod and a scraper; Wherein, the surface roughening assembly is used to be installed in the through groove of the top crossbeam, and the top crossbeam is provided with horizontally penetrating two-way guide grooves on both sides of the through groove, and the width of the rotating plate does not exceed the width of the through groove, and the rotating plate has short shafts on both sides for being installed in the two-way guide groove; wherein the short shaft on one side of the rotating plate extends out of the two-way guide groove for installing the angle adjuster; the rotating plate can move in the two-way guide groove through the short shaft to adjust its horizontal position relative to the sample compacting cylinder and the sample; The second operating member is installed above the rotating plate, the transmission arm passes through the rotating plate and is installed below the rotating plate, one end of the transmission arm is connected to the second operating member, and the other end is connected to the telescopic rod through a self-locking universal joint, and the hair scraper is installed at the bottom end of the telescopic rod; the rotating plate is used to control the inclination angle of the second operating member, the transmission arm, the telescopic rod and the hair scraper; The angle adjuster comprises a knob chassis and an angle knob, the surface of the knob chassis has an angle scale, and the angle knob has an angle reference line; the angle adjuster drives the short axis to rotate by rotating the angle knob, thereby driving the rotating plate to rotate so that the rotating plate is consistent with the inclination angle of the sample layer, and the rotation angle indicated by the angle reference line of the angle knob is configured to make the rotating plate parallel to the sample layer; The second operating member is used to control the transmission arm to rotate along its axis to drive the telescopic rod and the scraper to perform circular motion, so that the scraper can perform a scraping operation on the inclined surface of the sample; The scraper includes a scraper base, a scraper top plate, a scraper steel needle and a height-adjustable connecting piece; wherein the scraper base is fixedly mounted on the bottom end of the telescopic rod, the scraper top plate is spaced apart from and parallel to the scraper base via a height-adjustable connecting piece, the scraper steel needle is fixedly mounted on the lower end surface of the scraper base and passes through a plurality of fine holes of the scraper top plate; the height-adjustable connecting piece is used to control the distance between the scraper base and the scraper top plate so as to change the protruding length of the scraper steel needle at the scraper top plate.

[0011] In some embodiments of the present invention, the preparation device further comprises a sample cutting assembly, wherein the sample cutting assembly comprises an upper cutting group for cutting the upper end of the sample; The upper cutting group includes a rotating disk, a cutting disc, a fixed disk and a third operating member; wherein the cutting disc is sandwiched between the rotating disk and the fixed disk, and an internal threaded hole is provided at the center of the fixed disk for threaded connection with the upper end of the sample compacting cylinder, thereby realizing fixed installation of the fixed disk; The cutting blade disc comprises a plurality of groups of conical blades which are centrally symmetrical, and the inner long sides of the conical blades have cutting edges; A plurality of centripetal rotation guide grooves extending along an oblique line are provided on one side of the fixed disk facing the cutting blade disk, and a rectangular protruding guide shaft is provided on the end surface of each conical blade facing the fixed disk, the length of the centripetal rotation guide groove is greater than the length of the rectangular protruding guide shaft, and the widths of the two are the same; A strip groove is provided on one side of the conical blade facing the rotating disk, and a circular protruding guide shaft is provided on one side of the rotating disk facing the cutting blade disk, wherein the diameter of the circular protruding guide shaft is the same as the width of the strip groove; The rotating disk is provided with at least two arc-shaped guide grooves close to its outer edge, and the rotating disk is inserted into the arc-shaped guide grooves through at least two connecting pieces fixed on the fixed disk to realize rotatable connection with the fixed disk; the two sides of the arc-shaped guide groove in the horizontal direction are used to abut against the connecting pieces during the cutting process, thereby driving the cutting disc to rotate forward or reversely; The rotating disk has a hole in the center, and its hole diameter is larger than the outer diameter of the sample compacting cylinder. The third operating member is connected to the rotating disk, so that the rotating disk can be driven by the third operating member to rotate forward or reverse, thereby driving the various conical blades of the cutting disc to rotate centripetally along the centripetal rotating guide groove. During the centripetal rotation process, the regular polygon surrounded by the cutting edges gradually becomes smaller, thereby cutting the upper end of the sample.

[0012] In some embodiments of the present invention, the sample cutting assembly further comprises a lower cutting group for cutting the lower end of the sample; the fixing plate of the lower cutting group is used for threaded connection with the lower end of the sample compacting cylinder.

[0013] In some embodiments of the present invention, the pressurizing assembly includes a supporting disc, a supporting rod, a supporting plate, a sample pushing column, a tension spring and a lifting mechanism; The lifting mechanism includes any one of a hydraulic cylinder, a pneumatic cylinder and a motor drive mechanism, and is used for being fixedly mounted on the bottom base; The support disc is installed on the top of the lifting mechanism through the support plate, and its two sides are connected to the bottom base through tension springs; The support rod is installed on the top of the support disc and is used to connect with the sample cutting assembly or the sample compacting cylinder; The sample pushing column is a columnar structure with a certain length, and its outer diameter is not larger than the inner diameter of the sample compacting cylinder. It is used to be lifted by the lifting mechanism into the sample compacting cylinder and push the sample out.

[0014] In some embodiments of the present invention, the sample compacting cylinder further includes a fixing rod, a fixing collar, and a flat head rivet; Wherein, the fixing collar is used to be sleeved in the annular groove in the middle of the barrel, and the two sides of the fixing collar are fixedly connected to the fixing rod; A vertical slide groove penetrating in the horizontal direction is provided in the middle of the support column. The fixing rod is connected to the vertical slide groove through the flat head rivet at its end, and can be adjusted to a fixed connection or a slidable connection according to the positioning requirements of the cylinder body.

[0015] Another aspect of the present invention provides a method for preparing a triaxial test soil sample capable of simulating sedimentary bedding distribution, the method comprising: Step 1: According to the prefabricated bedding distribution angle requirements of the sample, select a pad with a suitable angle from the bedding angle control pad of the bedding angle positioning assembly and combine it with the top pressure head and the bottom pressure head; first, align the beveled surface of the selected bedding angle control pad with the beveled surface of the top pressure head, and nest it with the top pressure head through the trapezoidal guide rail on the beveled surface of the angle control pad; then, tighten the top pressure head and the bedding thickness control rod through threads; finally, fix the bottom pressure head to the bottom of the sample compaction cylinder through the positioning card hole, and rotate the sample compaction cylinder at the same time to ensure that the beveled surface of the bottom pressure head is parallel to the beveled surface of the top pressure head. At this time, the inclination angle of the bedding angle control pad is the distribution angle of the prefabricated bedding; Step 2: First, pour a single portion of soil material evenly into the bottom of the sample compacting cylinder equipped with a bedding angle control pad to prepare for sample compaction; secondly, move the bedding thickness control rod of the bedding angle positioning assembly along the top crossbeam of the frame to the top of the sample compacting cylinder, and drive the bedding thickness control rod to move downward relative to the top crossbeam by rotating the first operating member, and press it into the sample compacting cylinder, and then continue to drive the bedding thickness control rod to continuously penetrate into the sample compacting cylinder until the distance between the scale starting point of the bedding thickness control rod and the bottom reference line of the slider of the frame is equal to the preset bedding thickness of the sample, then the bedding thickness control rod can be stopped. The control rod is moved, and the sample compacting cylinder is rotated to align the second bedding orientation positioning mark at its bottom with the first bedding orientation positioning mark on the first operating member. At this time, the beveled surface of the top pressure head is parallel to the beveled surface of the bottom pressure head. Finally, the support plate of the pressure component is placed on the top of the hydraulic jack and aligned with the center hole of the support disc. The pressure component is then started to push the support disc upward, thereby pushing the sample compacting cylinder upward along the vertical slide groove of the support column of the frame. The relative movement of the first die and the second die is achieved through the reaction force of the bedding angle positioning component to complete the compaction of the single-layer bedding of the sample. Step 3: After the single-layer bedding preparation of the sample is completed, first, the sample compacting cylinder is reset to its initial position downward along the vertical slide groove of the support column of the frame through the pressure component at the bottom of the frame, and the bedding thickness control rod of the bedding positioning component is slowly disengaged from the sample compacting cylinder upward by rotating the first operating member. When it is completely out of the top of the sample compacting cylinder, the bedding thickness control rod is moved to one side of the top crossbeam of the frame through the slider mechanism; then, the layer roughening component is moved to the top of the sample compacting cylinder through the double-direction guide groove of the top crossbeam of the frame, and the rotating plate is driven to rotate by rotating the angle knob, and when it is tilted, the bedding thickness control rod is moved to the side of the top crossbeam of the frame. When the oblique direction is parallel to the spreading direction of the sample layer, the rotation angle knob is locked by the pin; finally, the telescopic rod is spread vertically by adjusting the self-locking universal joint, and the distance between the scraping top plate and the scraping bottom plate of the scraper is adjusted by the bolt, and then the extension length of the scraping steel needle is set according to the test requirements, and at the same time, the length of the telescopic rod is adjusted so that the scraping steel needle of the scraper at the bottom is inserted into the surface of the sample layer, and then the second operating member is rotated to drive the transmission arm to rotate, and then the telescopic rod is driven to drive the scraper to perform repeated circular scraping motions along the inclined sample layer, so as to complete the roughening treatment of the contact layer of the sample; Step 4: After the roughening of the first layer of the sample is completed, the compaction of each layer of soil can be gradually completed according to the number of sample layers. First, the layer roughening component needs to be reset to the initial state and initial position before step 3. The scraper can be driven out of the sample compaction cylinder through the telescopic rod of the layer roughening component, and the layer roughening component can be moved to the other side of the top beam through the double guide groove of the top beam of the frame. Secondly, according to the number of layers required for sample preparation, steps 2 and 3 are repeated continuously to complete the compaction of each layer of soil and the roughening of the layer until the last layer of soil is compacted. After the compaction is completed, an oblique cylindrical sample with a preset layer distribution can be obtained; finally, the sample compaction cylinder is locked on the vertical slide groove of the support column of the frame through the fixing rod, and the supporting disc is driven downward by the pressure component, so that the fixed disc of the cutting component is separated from the bottom of the sample compaction cylinder, and then the bottom pressure head fixed at the bottom of the sample compaction cylinder is taken out, and then the supporting disc is moved upward again by the pressure component to drive the fixed disc of the cutting component to contact with the bottom of the sample compaction cylinder, and then the fixed disc is tightened and fixed to the bottom of the sample compaction cylinder through the threaded bayonet to prepare for sample cutting; Step 5: First, move the sample compacting cylinder downward along the vertical slide groove of the support column of the frame to separate the top pressure head of the layer from the sample surface. When the bottom of the top pressure head just separates from the top of the sample compacting cylinder, stop the movement of the sample compacting cylinder, and turn the first operating member to drive the layer thickness control rod to move downward and press into the sample compacting cylinder, so that it is in close contact with the top surface of the sample again; secondly, start the pressurizing assembly to drive the sample compacting cylinder to move upward along the frame, and then cooperate with the layer thickness control rod to slowly remove the sample from the bottom of the sample compacting cylinder through the reaction force. When the sample compacting cylinder is in close contact with the slider mechanism of the top crossbeam of the frame, the beveled cylindrical surface at the bottom of the sample is also completely removed from the bottom of the sample compacting cylinder, and then the rotating disk of the sample cutting assembly is driven to rotate through the third operating member, thereby driving the conical blade of the cutting disc to rotate synchronously. The concentric rotation process of multiple sets of conical blades causes the blade edges to continuously cut the sample radially, thereby achieving the test The sample cutting assembly radially cuts the beveled cylinder at the bottom of the bedding sample; finally, after the beveled cylinder at the bottom of the bedding sample is flattened, the first operating member is rotated to drive the bedding thickness control rod to move upward to make it disengage from the sample compacting cylinder again, and it is moved to one side along the top crossbeam of the frame through the slider mechanism, and at the same time, the sample pushing rod is passed through the center of the supporting disc and threadedly connected with the hydraulic jack, and the top of the sample pushing rod is made to contact the sample at the bottom of the sample compacting cylinder, and then the hydraulic jack of the pressurizing assembly is started to drive the sample pushing rod to move upward, so that the sample can be slowly disengaged upward along the sample compacting cylinder, and when the beveled cylindrical surface at the top of the sample just disengages from the top of the sample compacting cylinder, the sample cutting assembly fixed on the top of the sample compacting cylinder is used to radially cut the beveled cylinder at the top of the sample, and the cutting steps and process are consistent with the cutting operation at the bottom of the sample, and after the beveled cylinder at the top of the sample is completely flattened, the cutting work of the bedding sample is completed; Step 6: After completing the cutting of the bedding sample, continue to drive the sample pushing rod fixedly connected to the hydraulic jack of the pressurizing assembly to move upward so that it pushes the sample slowly out of the top of the compaction cylinder through the center hole of the support disc. When the bedding sample is completely out of the top of the sample compaction cylinder, the demoulding work of the bedding sample is completed, and a standard triaxial test sample with a preset bedding structure is obtained.

[0016] Compared with the complex process of traditional manual cutting and trimming, the preparation device in the embodiment of the present invention can complete the high-precision bedding sample preparation in a shorter time, greatly improving the preparation efficiency; through precise die and bedding thickness control, the accuracy and consistency of the bedding structure and soil layer distribution of each sample can be guaranteed; the adjustable bedding thickness control and replaceable die design enable the device to simulate different types of sedimentary bedding to meet different research needs; compared with traditional cutting methods, die molding can better maintain the natural structure of the soil sample, avoid structural damage caused by the cutting process, and ensure the representativeness and accuracy of the sample.

[0017] Additional advantages, purposes, and features of the present invention will be described in part in the following description, and will become apparent to those skilled in the art after studying the following, or may be learned from the practice of the present invention. The purposes and other advantages of the present invention may be achieved and obtained by the structures specifically indicated in the specification and the accompanying drawings.

[0018] Those skilled in the art will appreciate that the objectives and advantages that can be achieved with the present invention are not limited to the above specific description, and the above and other objectives that can be achieved by the present invention will be more clearly understood from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present invention, constitute a part of this application, and do not constitute a limitation of the present invention. The components in the drawings are not drawn to scale, but are only for illustrating the principles of the present invention. In order to facilitate the illustration and description of some parts of the present invention, the corresponding parts in the drawings may be enlarged, that is, they may become larger relative to other components in the exemplary device actually manufactured according to the present invention. In the drawings: Figure 1 It is a schematic diagram of the three-dimensional structure of a triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution in one embodiment of the present invention.

[0020] Figure 2 It is a structural schematic diagram of a layer positioning component in one embodiment of the present invention.

[0021] Figure 3 It is a schematic structural diagram of a top pressure head, a bottom pressure head and a bedding angle control pad in one embodiment of the present invention.

[0022] Figure 4 Schematic diagram of the structure of a layer roughening component in one embodiment of the present invention.

[0023] Figure 5 for Figure 4 The partial enlarged view at point A in the middle is a schematic diagram of the structure of the hair scraper.

[0024] Figure 6 for Figure 4 The local enlarged view of point B in the middle is a schematic diagram of the structure of the angle adjuster.

[0025] Figure 7 It is a schematic structural diagram of a sample compacting cylinder in one embodiment of the present invention.

[0026] Figure 8 It is a schematic structural diagram of an upper cutting group of a sample cutting assembly in one embodiment of the present invention.

[0027] Reference numerals: 1. Bedding positioning assembly; 11. First operating member; 12. Bedding thickness control rod; 131. Top pressure head; 132. Bottom pressure head; 14. Bedding angle control pad; 2. surface roughening assembly; 21. second operating member; 22. rotating plate; 23. angle adjuster; 231. knob chassis; 232. pin; 233. angle knob; 24. transmission arm; 25. self-locking universal joint; 26. telescopic rod; 27. scraper; 271. scraper top plate; 272. scraper chassis; 273. height-adjustable connector; 274. scraper steel needle; 3. Frame; 31. Top crossbeam; 311. Through slot; 312. Double guide slot; 32. Slider mechanism; 33. Support column; 331. Vertical slide slot; 34. Bottom base; 4. Sample compacting cylinder; 41. Cylinder body; 42. Fixing rod; 43. Fixing collar; 44. Flat head rivet; 5. Sample cutting assembly; 51. Rotating disk; 511. Circular raised guide shaft; 512. Arc guide groove; 52. Cutting disc; 521. Conical blade; 522. Strip groove; 53. Fixed disk; 531. Centripetal rotating guide groove; 54. Screw; 55. Third operating member; 6. Pressurizing assembly; 61. Support disc; 62. Support rod; 63. Support plate; 64. Sample push rod; 65. Tension spring; 66. Lifting mechanism. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0029] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solutions according to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0030] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, elements, steps or components, but does not exclude the presence or addition of one or more other features, elements, steps or components.

[0031] It should also be noted that, unless otherwise specified, the term “connection” herein may refer not only to a direct connection but also to an indirect connection involving an intermediate.

[0032] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

[0033] In the field of geotechnical engineering, especially when it comes to the study of layered soil and sedimentary bedding, how to accurately prepare triaxial test specimens containing sedimentary bedding has always been a technical problem. The traditional triaxial specimen preparation method has certain limitations and cannot directly simulate the distribution of sedimentary bedding, which affects the accuracy and representativeness of the experimental results. The embodiment of the present invention provides a triaxial test soil sample preparation device and preparation method that can simulate the distribution of sedimentary bedding, so that layered triaxial test specimens that can simulate the deposition thickness and deposition angle of any soil layer can be quickly prepared, greatly improving the preparation efficiency and finished product quality of the bedding specimens. In addition, the device is integrated and automated, simple to operate, stable in operation, and can also cover all functions of specimen preparation, cutting, and demolding.

[0034] In a first aspect, the present invention provides a triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution, such as Figure 1-Figure 3 As shown, the preparation device includes: a frame 3, a sample compacting cylinder 4, a bedding positioning assembly 1, and a pressurizing assembly 6. In this embodiment, the frame 3 is used to support the entire device structure; the sample compacting cylinder 4 is mainly used to accommodate the sample, which is convenient for compaction and bedding control in the chamber; the bedding positioning assembly 1 is a core component, which is used to control the thickness and angle of the deposited bedding; the pressurizing assembly 6 is responsible for applying a pressing force to ensure the formation and uniformity of the bedding structure.

[0035] like Figure 1 As shown, the sample compacting cylinder 4 includes a cylinder body 41 ( Figure 1 The barrel 41 in the figure is partially cut to show the internal structure clearly. The barrel 41 has a chamber for accommodating the sample and is arranged through. The barrel 41 can be a hollow rigid cylinder with a smooth internal surface, which can ensure the uniformity and stability of the sample during the compaction process.

[0036] like Figure 2 and Figure 3 As shown, the bedding positioning assembly 1 includes a bedding thickness control rod 12, a first die and a second die. Among them, the bedding thickness control rod 12 is used to accurately control the thickness of each sedimentary layer to ensure the thickness consistency between different layers or adjust the thickness according to actual needs. The first die and the second die have extrusion surfaces that match each other. The extrusion surfaces of the two dies are used to directly contact with the sample to extrude the bedding structure. The extrusion surfaces of the two dies are parallel or non-parallel to each other, and the extrusion surfaces are set to be smooth or rough, flat or curved. The extrusion surfaces of the two dies are responsible for directly contacting the soil sample to extrude the sedimentary bedding structure.

[0037] In some embodiments, mutually parallel extrusion surfaces can be used to represent the uniformity of stratigraphic deposition; for example, parallel bedding structures are common in relatively stable depositional environments such as lakes and ocean deposits, indicating that sediments are uniformly deposited on the horizontal plane, and the parallelism between layers reflects relatively stable depositional conditions. Non-parallel extrusion surfaces are suitable for simulating deformation or uneven depositional environments of geological structures. Non-parallel bedding usually appears in areas of stress, deformation or erosion, and can reflect that the strata are affected by folds, faults or impacts, or that there are obvious directional changes in the depositional environment. For example, in scenes such as river environments, wind and sand deposits, and tectonic belts, sediments usually form non-parallel sedimentary layers due to factors such as water flow, wind, and crustal movement, showing tilt, folds, or other non-uniform characteristics of the bedding.

[0038] In other embodiments, a smooth extrusion surface can be used to simulate the relatively uniform and smooth stratification structure in the natural sedimentation process, such as the sedimentary layers in lakes or deep water environments; while a rough extrusion surface is used to simulate the sedimentary environment with stronger friction or coarser particles, such as the stratification structure in rivers, aeolian deposits or terrestrial deposits.

[0039] In some other embodiments, the selection of a flat or curved extrusion surface may be to simulate different geological or sedimentary scenarios. A flat extrusion surface is used to simulate the uniform deposition of sediments in a horizontal or relatively flat environment. A curved extrusion surface may be used to simulate the uneven topography or the non-uniform deposition process of sediments under the action of external forces. For example, in a river, sandstorm or tidal environment, the deposition of sediments is often affected by topography or fluid mechanics, forming a curved surface structure. Alternatively, a curved extrusion surface is used to simulate a geological environment affected by folds, faults or tectonic movements, where the strata are bent or tilted due to tectonic activity or sedimentary differences.

[0040] In the above embodiments, the first die and the second die at least include a plurality of replaceable dies with different tilt angles for controlling different bedding angles. The die has a plurality of replaceable options with different tilt angles, which can simulate bedding structures with different deposition angles and enhance the adaptability and flexibility of the device.

[0041] When the preparation device is pressing the sample stratification, the stratification thickness control rod 12 and the pressure assembly 6 are respectively installed on both sides of the barrel 41 and fixed to the frame 3, the first die is fixedly installed at the end of the stratification thickness control rod 12, the second die is installed at the end of the barrel 41 facing the pressure assembly 6, or the second die is fixedly installed at the movable end of the pressure assembly 6, and at least one of the first die and the second die can be extended into the barrel 41.

[0042] In the above embodiment, the pressure component 6 works in conjunction with the bedding positioning component 1 to ensure that the pressure applied to the sample is uniform. The component can accurately control the bedding structure of the sample by adjusting the pressure size and direction, thereby ensuring the high quality and high consistency of the experimental sample. The compaction process of the device can have a variety of options, such as extending the bedding thickness control rod 12 and the pressure component 6 into the barrel 41, setting the bedding thickness control rod 12 to be fixed, and controlling the final thickness of the sample through the stroke of the pressure component 6, thereby achieving the control of the bedding thickness. In addition, since the force of the pressure component 6 is large, the second die can also be fixed on the barrel 41, and the pressure component 6 can achieve the sample bedding compaction by pushing the entire barrel 41 and the second die, combined with the reaction force of the fixed different bedding thickness control rods 12.

[0043] Compared with the complex process of traditional manual cutting and trimming, the preparation device in the embodiment of the present invention can complete the high-precision bedding sample preparation in a shorter time, greatly improving the preparation efficiency; through precise die and bedding thickness control, the accuracy and consistency of the bedding structure and soil layer distribution of each sample can be guaranteed; the adjustable bedding thickness control and replaceable die design enable the device to simulate different types of sedimentary bedding to meet different research needs; compared with traditional cutting methods, die molding can better maintain the natural structure of the soil sample, avoid structural damage caused by the cutting process, and ensure the representativeness and accuracy of the sample.

[0044] The triaxial test soil sample preparation device and preparation method provided by the present invention can simulate the distribution of sedimentary bedding, overcome the limitations of traditional preparation methods, accurately simulate the distribution, thickness and angle of sedimentary bedding, significantly improve the preparation efficiency and finished product quality of triaxial test samples, and have high application value. By accurately controlling the bedding structure, the device provides a more realistic and reliable soil sample preparation scheme for experimental research in geotechnical engineering, which helps to improve the representativeness and accuracy of experimental results.

[0045] In some embodiments, Figure 1-Figure 3 As shown, the sample compacting cylinder 4 is arranged in the vertical direction, but is not limited to this. The device can be designed as a vertical structure (the axis of the cylinder body 41 is along the vertical direction) or a horizontal structure (the axis of the cylinder body 41 is along the horizontal direction), but is not limited to this. It can also be designed at any angle, such as tilted placement.

[0046] The die in the embodiment of the present invention can be designed to be replaceable as a whole. For example, by using a quick-plug connector connection, the first die and the second die can be designed as an integral structure with an extrusion surface. If sample stratification with different stratification angles needs to be prepared, the die can be made smoother as a whole.

[0047] In addition, the die can also be designed as a split structure, such as Figure 3 As shown, as at least one achievable method, the first die includes a top die 131, the second die includes a bottom die 132, and the first die and the second die also include a matching bedding angle control pad 14. In this solution, the top die 131 and the bottom die 132 can be used as mounting seats for the top die 131. Considering that the inclination angles of the two bedding angle control pads 14 of the upper and lower dies need to remain unchanged during the preparation process, the connection method can use a relatively simple threaded connection to achieve the connection between the die and other structural parts, and the connection on the die of the bedding angle control pad 14 can use a dovetail groove structure for plug-in limiting to prevent it from rotating.

[0048] Specifically, the upper end of the top pressure head 131 has a threaded hole or a threaded column for threaded connection with the bottom end of the bedding thickness control rod 12. The lower end of the bottom pressure head 132 has a cylindrical section, which is used to connect with the lower end of the sample compacting cylinder 4; the bottom pressure head 132 can be inserted into the cylinder body 41, and the outer diameter of the cylindrical section is larger than the inner diameter of the cylinder body 41, which serves as a blocking structure at the bottom of the cylinder body 41 to ensure reliable fixation between the compacting cylinder and the bottom pressure head 132; in order to prevent the cylinder body 41 and the bottom pressure head 132 from rotating relative to each other, a groove can be opened at the bottom of the cylinder body 41, and a protrusion is designed at the corresponding position of the bottom pressure head 132, and the relative rotation is limited by the cooperation of the two. As at least one achievable method, a second bedding orientation positioning mark is provided at the bottom of the cylinder body 41, which is used to indicate the inclination orientation of the extrusion surface of the second die. The notch opened at the bottom of the cylinder body 41 can be used as a second bedding orientation positioning mark to indicate the distribution direction of the sample layer.

[0049] Furthermore, if Figure 3 As shown, the lower end of the top pressure head 131 and the upper end of the bottom pressure head 132 both have a pad connection portion, and the pad connection portion includes a mounting bevel and a slot structure (which can be designed as a dovetail groove shape). The end of the bedding angle control pad 14 facing the pad connection portion has a pressure head connection portion, and the pressure head connection portion includes another bevel of the same shape as the mounting bevel of the pressure head, and a trapezoidal guide rail protrusion matching the slot structure. The trapezoidal guide rail protrusion and the slot structure between the pad and the pressure head connection portion enable the pad to stably cooperate with the connection portion of the pressure head, and ensure accuracy and firmness during the installation process. The pressure head connection portion is designed to have the same shape as the bevel of the pressure head, which can firmly fix the bedding angle control pad 14 and ensure that the pad always maintains the correct position and angle during the compaction process.

[0050] As at least one possible implementation, Figure 3As shown, the top pressure head 131 and the bottom pressure head 132 are both designed as beveled cylinders, wherein a threaded top cap (threaded column) is provided on the top of the top pressure head 131 for detachable connection with the bedding thickness control rod 12; the connection between the bottom pressure head 132 and its cylindrical section can be an integral structure or a split threaded detachable connection structure. If the two are an integral structure, the slot structure can have an opening at its top to facilitate the entry of the pad.

[0051] In the above embodiment, the bottom pressure head 132 and the top pressure head 131 are designed as a common mounting seat of the bedding angle control pad 14 with different inclination angles; the bedding angle control pad 14 includes a plurality of or even a series of replaceable modules with different inclination angles, all of which are designed as rigid beveled cone structures. This structure improves the rigidity and durability of the pad. By replacing modules with different inclination angles, the bedding angle formed during the compaction process can be accurately controlled to meet the experimental requirements of different geological and sedimentary conditions.

[0052] The modular design of the bedding angle control pad 14 in the embodiment of the present invention makes the device have good adjustability and flexibility. The design of the device makes it an effective tool for compacting samples such as soil and rock and simulating the changes in bedding structure in geological environments by accurately controlling the bedding angle and various parameters in the compaction process. By positioning the nested combination of the pressure head and the bedding angle control pad 14, a layer pressing mold with an arbitrary inclination angle can be formed to achieve control of the bedding angle during the sample pressing process. Experimenters can adjust various factors such as bedding angle and thickness as needed to better study the deposition, compaction and geological change processes.

[0053] In some embodiments, Figure 1As shown, the frame 3 is a frame structure, including a top crossbeam 31, a slider mechanism 32, support columns 33 arranged on both sides and a bottom base 34; the support columns 33 arranged on both sides are fixedly arranged on the bottom base 34, and the top crossbeam 31 is fixedly arranged on the two support columns 33. The various components of the frame 3 can be fixedly connected by bolts or screws, etc. The combination of the support columns 33 and the bottom base 34 provides structural rigidity and stability, so that the frame 3 can withstand the action of external forces while maintaining structural accuracy. The compactness of the frame structure design helps to reduce the occupied space, and the coordination of various parts (such as the layer positioning component 1, the layer roughening component 2, etc.) enables the device to operate efficiently. The middle part of the top crossbeam 31 has a through slot 311 that is arranged to penetrate in the vertical direction, and the slider mechanism 32 is installed at the through slot 311. The slider mechanism 32 is configured to be able to move horizontally along the extension direction of the through slot 311. The through slot 311 can be used as a mounting slot for the layer positioning assembly 1. The horizontal movement of the slider can be precisely controlled by the cooperation between the through slot 311 and the slider mechanism 32. The through slot 311 acts as a guide rail to reduce the shaking or deviation of the layer positioning assembly 1, thereby improving the accuracy.

[0054] In some embodiments, Figure 2 As shown, the bedding thickness control rod 12 of the bedding positioning assembly 1 has an external thread for threaded connection with the slider of the slider mechanism 32, so that the bedding thickness control rod 12 is installed in the through groove 311 through the slider mechanism 32. The slider mechanism 32 also includes a locking member for locking the position of the slider mechanism 32 and the bedding thickness control rod 12. The locking member described here can be a locking nut, or can be matched through an axial hole at a specific position, such as the slider and the top crossbeam 31 are both provided with a vertical positioning hole, and the horizontal limit is achieved by a pin inserted in the positioning hole.

[0055] In this way, the control rod can be firmly mounted on the slider and can be moved horizontally or vertically along the through slot 311 through the slider mechanism 32; the horizontal movement is to avoid the position and move the axis position of the barrel 41 so that the scraper 27 can enter the barrel 41 to scrape the compacted sample layer. The external thread connection makes the adjustment process more accurate and reliable, and has a certain stability and locking performance.

[0056] like Figure 2As shown, the bedding thickness control rod 12 is also provided with a length scale distributed along its axial direction, which is used to determine the depth of the bedding thickness control rod 12 under the slider in combination with the bottom reference surface of the slider to adjust the bedding thickness of the sample. The length scale can be engraved in the thread, and the adjustment of the depth can change the bedding thickness, thereby adjusting the bedding thickness of the sample. The role of the length scale is to provide an intuitive adjustment scale so that the operator can accurately control and set the bedding thickness.

[0057] In the above embodiment, the bottom reference surface of the slider may be engraved with a reference line for determining the vertical moving distance of the bedding thickness control rod 12. In other embodiments, the bedding thickness may be controlled by controlling the moving distance of the pressurizing assembly 6, such as by using a motor drive with adjustable and controllable stroke, or by using a position-adjustable stroke switch, a distance sensor, etc.

[0058] Furthermore, the bedding positioning assembly 1 also includes a first operating member 11 arranged on the top of the bedding thickness control rod 12, which is used to control the rotation of the bedding thickness control rod 12; the first operating member 11 can be a manually controlled handwheel, handle or similar structure, or it can be an automatically controlled structure such as a motor. The first operating member 11 or the bedding thickness control rod 12 is provided with a first bedding orientation positioning mark, which is used to indicate the inclination orientation of the extrusion surface of the first die. This design can help the operator determine the relative inclination angle of the die, ensure the correct positioning of the die and the accurate formation of the bedding during operation. The mark of the inclination orientation can be a scale line, arrow or other visual mark, so that the operator can operate according to the mark.

[0059] In some embodiments, Figure 1 and Figure 4 As shown, the preparation device further includes a layer roughening component 2, and the layer roughening component 2 includes a second operating member 21, a rotating plate 22, an angle adjuster 23, a transmission arm 24, a telescopic rod 26 and a scraper 27, etc.

[0060] The surface roughening assembly 2 is used to be installed in the through groove 311 of the top crossbeam 31. The top crossbeam 31 is provided with horizontally penetrating bidirectional guide grooves 312 on both sides of the through groove 311, which provides an installation position and a range of motion for the subsequent rotating plate 22 (such as Figure 1The rotating plate 22 is located at the right half of the axis of the cylinder body 41 shown in the figure). The width of the rotating plate 22 does not exceed the width of the through groove 311, allowing the rotating plate 22 to move and flip freely in the groove. The rotating plate 22 has short shafts on both sides for installation in the two-way guide groove 312; wherein the short shaft on one side of the rotating plate 22 extends out of the two-way guide groove 312 for installation of the angle adjuster 23; the rotating plate 22 can move in the two-way guide groove 312 through the short shaft to adjust its horizontal position relative to the sample compacting cylinder 4 and the sample.

[0061] Further, the second operating member 21 is installed above the rotating plate 22, and the rotating plate 22 can be a steel square plate with a central opening. The transmission arm 24 passes through the rotating plate 22 and is installed below the rotating plate 22. One end of the transmission arm 24 is connected to the second operating member 21, and the other end is connected to the telescopic rod 26 through a self-locking universal joint 25. The scraper 27 is installed at the bottom end of the telescopic rod 26. The rotating plate 22 is used to control the inclination angle of the second operating member 21, the transmission arm 24, the telescopic rod 26 and the scraper 27. The second operating member 21 can be designed as a manually controlled wheel, handle, knob or other structure, or as an automatic structure controlled by a motor, and its function is to control the transmission arm 24 to rotate along the center of the opening of the rotating plate 22. Through the rotation of the transmission arm 24, the telescopic rod 26 and the scraper 27 make a circular motion, so that the scraper 27 can perform a precise scraping operation along the surface of the sample.

[0062] Furthermore, if Figure 6 As shown, the angle adjuster 23 can manually adjust the inclination angle of the rotating plate 22 so that it remains parallel to the top surface of the sample bedding. As at least one achievable method, the angle adjuster 23 includes a knob chassis 231 and an angle knob 233, the surface of the knob chassis 231 has an angle scale, and the angle knob 233 has an angle reference line; the angle adjuster 23 drives the short axis to rotate by rotating the angle knob 233, thereby driving the rotating plate 22 to rotate so that it is consistent with the inclination angle of the sample layer, and the rotation angle indicated by the angle reference line of the angle knob 233 is configured to make the rotating plate 22 parallel to the sample bedding. The fixing of the angle knob 233 can be achieved by means of a pin 232 at its end.

[0063] Furthermore, the second operating member 21 is used to control the transmission arm 24 to rotate along its axis, so as to drive the telescopic rod 26 and the scraper 27 to perform circular motion, so that the scraper 27 can perform a scraping operation on the inclined surface of the sample. Figure 5As shown, the scraper 27 includes a scraper bottom plate 272 , a scraper top plate 271 , a scraper steel needle 274 and a height-adjustable connector 273 ; wherein the scraper bottom plate 272 is fixedly mounted on the bottom end of the telescopic rod 26 .

[0064] The scraping top plate 271 is spaced apart from and parallel to the scraping bottom plate 272 through a height-adjustable connector 273. The scraping steel needle 274 is fixedly mounted on the lower end surface of the scraping bottom plate 272 and passes through a number of fine holes of the scraping top plate 271. The scraping steel needle 274 can be set to any density and thickness according to actual conditions. The height-adjustable connector 273 is used to control the spacing between the scraping bottom plate 272 and the scraping top plate 271 to change the extension length of the scraping steel needle 274 at the scraping top plate 271 (in this embodiment, the extension length range of the scraping steel needle 274 can be designed to be 2-8mm). The length and position of the steel needle can be controlled by adjusting the distance between the top plate and the bottom plate, thereby achieving different degrees of surface roughening effects. The height-adjustable connector 273 can use threaded connectors, such as bolts and studs, which can easily adjust the fixed position.

[0065] It is understandable that, since the surface roughening component 2 is arranged above the barrel 41, the top of the sample can be scraped. If the lower end needs to be scraped, the sample can be turned over. In addition, in order to facilitate the scraper 27 to extend into the barrel 41 for scraping, the diameter of the scraper 27 can be designed to be smaller than the inner diameter of the barrel 41; of course, the pressurizing component 6 can also be used to push the sample so that its top is separated from the top of the barrel 41 and exposed. At this time, the scraper 27 does not need to extend into the barrel 41, and its diameter can be any size, as long as the top of the sample can be completely covered during the circumferential scraping process.

[0066] In the above embodiment, the present invention can achieve precise control of the roughening of the surface layer of the sample through the design of the angle adjuster 23 and the adjustable scraper 27. Whether adjusting the inclination angle of the scraper 27 or controlling the extension length of the scraping steel needle 274, the stability and consistency of the process can be ensured. The device is suitable for various samples that need to adjust the surface roughness, especially in material surface treatment, surface roughness experiments or laboratory research. The device has a simple structure, the operating parts are easy to operate, and the angle scale and rotation mechanism allow the operator to quickly and accurately adjust the device to reduce human errors.

[0067] In some embodiments, in order to realize the sample cutting function in an integrated manner, the preparation device further includes a sample cutting component 5, such as Figure 1 and Figure 8As shown, the sample cutting assembly 5 includes an upper cutting group for cutting the upper end of the sample; the upper cutting group includes a rotating disk 51, a cutting disc 52, a fixed disk 53 and a third operating member 55; wherein the cutting disc 52 is clamped between the rotating disk 51 and the fixed disk 53, and an internal threaded hole is provided at the center of the fixed disk 53 for threaded connection with the upper end of the sample compacting cylinder 4, thereby achieving fixed installation of the fixed disk 53.

[0068] The cutting blade 52 includes a plurality of groups of conical blades 521 ( Figure 8 In the embodiment, there are four groups, each group includes two blades), the inner long side of the conical blade 521 has a cutting edge; the centers of the multiple groups of conical blades 521 can be surrounded by a regular polygon shape (or the inscribed circle can be regarded as a reference circle), and these conical blades 521 can move inward along the extension of the cutting edge (centripetal movement). The side of the fixed disk 53 facing the cutting blade disk 52 is provided with a plurality of centripetal rotation guide grooves 531 extending along the oblique line. The guide grooves can be regarded as extending along the tangent direction of the reference circle. In the straight direction, these guide grooves provide guidance for the subsequent blade movement. The end face of each conical blade 521 facing the fixed disk 53 is provided with a rectangular protruding guide shaft, the length of the centripetal rotation guide groove 531 is greater than the length of the rectangular protruding guide shaft, and the widths of the two are the same; the design of the cutting blade disk 52 is to ensure that the blade can move stably according to the set trajectory during rotation through the centripetal rotation guide groove 531 and the rectangular protruding guide shaft.

[0069] The side of the conical blade 521 facing the rotating disk 51 (such as Figure 8 The upper end surface of the rotating disk 51 is provided with a strip groove 522, and a circular protruding guide shaft 511 is provided on the side of the rotating disk 51 facing the cutting blade disk 52. The diameter of the circular protruding guide shaft 511 is the same as the width of the strip groove 522, and the length of the strip groove 522 is greater than the guide shaft diameter. The design of the strip groove 522 and the circular protruding guide shaft 511 ensures a stable connection between the rotating disk 51 and the cutting blade disk 52. The circular protruding guide shaft 511 and the rectangular strip groove 522 also ensure that the conical blade 521 can be driven by the rotation of the rotating disk 51.

[0070] The rotating disk 51 is provided with at least two arc-shaped guide grooves 512 near its outer edge (as shown in the figure, the length of which is approximately 1 / 4 of the circumference of the rotating disk 51). The rotating disk 51 is inserted into the arc-shaped guide grooves 512 through at least two connecting pieces fixed on the fixed disk 53 to achieve rotatable connection with the fixed disk 53. The connecting piece can be a screw 54, that is, the fixed disk 53 is also provided with a corresponding threaded hole, and the screw 54 can axially limit the rotating disk 51 to avoid separation from the fixed disk 53 and the limiting position of the screw 54. The two sides of the arc-shaped guide groove 512 are fixed in the horizontal direction to abut against the connecting piece during the cutting process, thereby driving the cutting blade 52 to rotate forward or reverse. The rotating disk 51 has a central hole, the diameter of which is larger than the outer diameter of the sample compacting cylinder 4. The third operating member 55 is connected to the rotating disk 51, so that the rotating disk 51 can be driven by the third operating member 55 to rotate forward or reverse, thereby driving the various conical blades 521 of the cutting blade disk 52 to rotate centrifugally along the centripetal rotation guide groove 531, thereby completing the synchronous radial cutting of the sample by multiple groups of conical blades 521. In other words, during the centripetal rotation process, the size of the regular polygon surrounded by the cutting edges of each conical blade 521 gradually decreases, thereby cutting the upper end of the sample. The third operating member 55 can be a handle or a hand wheel.

[0071] It can be understood that in order to cut the lower end of the sample, the sample cutting assembly 5 also includes a lower cutting group for cutting the lower end of the sample; the fixing plate 53 of the lower cutting group is used to be threadedly connected with the lower end of the sample compacting cylinder 4. The structures of the upper and lower cutting groups are mirror-symmetrical along the horizontal plane, and will not be repeated here.

[0072] In the above embodiment, these designs ensure that the conical blade 521 can rotate stably along a predetermined path, and avoid deviation or jamming by accurately guiding the direction of the blade. The design of the arc guide groove 512 and the connecting piece enables the rotating disk 51 to rotate stably during the cutting process, maintaining the stable contact between the cutting disc 52 and the sample. The design of the conical blade 521 not only provides a better cutting effect, but also ensures that the cutting area gradually decreases during the cutting process through centripetal rotation, and the cutting effect is more uniform. This sample cutting assembly 5 can achieve precise cutting of the upper end of the sample through the interaction of the precisely designed rotating disk 51, the cutting disc 52 and the fixed disc 53. Through the control of the third operating member 55, the cutting process can be flexibly adjusted to meet different cutting requirements. This design has high operability and stability, and is suitable for high-precision laboratory sample preparation and material cutting work.

[0073] In some embodiments, Figure 1As shown, the pressurizing assembly 6 includes a supporting disc 61, a supporting rod 62, a supporting plate 63, a sample pushing column, a tension spring 65, and a lifting mechanism 66. The pressurizing assembly 6 is designed to achieve pressurized preparation of the sample, and pushing and ejecting the sample after preparation through the coordinated action of a series of components.

[0074] The lifting mechanism 66 includes any one of a hydraulic cylinder, a pneumatic cylinder and a motor drive mechanism, which is fixedly mounted on the bottom base 34. Through the operation of these mechanisms, the required vertical driving force can be provided. In the embodiment of the present invention, a hydraulic jack can be selected, which can achieve the required compaction function in a relatively simple manual control method and at a relatively low cost.

[0075] Furthermore, the support disc 61 is installed on the top of the lifting mechanism 66 through the support plate 63, and its two sides are connected to the bottom base 34 through tension springs 65; the support disc 61 serves as a connection platform and can provide support and stability. The tension spring 65 is used for the rapid and stable reset of the pressurizing component 6, and can also prevent damage to components due to excessive pressure or too fast movement.

[0076] Furthermore, the support rod 62 is installed on the top of the support disc 61, and is used to connect with the sample cutting assembly 5 or the sample compacting cylinder 4; the support rod 62 can provide a three-dimensional space for placing the sample pushing column; the support rod 62 also plays a role of stable support, ensuring that the sample will not be unnecessarily deviated or disturbed during the compaction or cutting process.

[0077] Furthermore, the sample pushing column is a columnar structure with a certain length, and a steel cylinder may be selected, whose outer diameter is not larger than the inner diameter of the sample compacting cylinder 4, and is used to be lifted by the lifting mechanism 66 into the sample compacting cylinder 4 and push the sample out from the top of the cylinder body 41.

[0078] In the above embodiment, the design of the pressurizing assembly 6 provides an efficient, adjustable and stable way to pressurize, push and push out the sample through the coordinated work of multiple components. The lifting mechanism 66 provides the driving force, the support disc 61 and the support rod 62 ensure the stability of the device, the sample column accurately enters the sample compacting cylinder 4 and pushes the sample, and the tension spring 65 provides elasticity and stability. This design can not only meet different test requirements, but also ensure safety and accuracy during operation.

[0079] In the embodiment of the present invention, the barrel 41 can be set to be movable or fixed in the vertical direction according to actual operation requirements. In order to facilitate changing its connection form, a special connection method can be designed. Figure 1 and Figure 7 As shown, the sample compacting cylinder 4 further includes a fixing rod 42, a fixing collar 43 and a flat head rivet 44, etc.

[0080] The fixing collar 43 is used to be sleeved in the annular groove in the middle of the barrel 41, and the fixing collar 43 is fixedly connected to the fixing rod 42 on both sides; in this way, the fixing collar 43 provides the middle positioning of the barrel 41, ensuring that it can remain stable during operation and prevent displacement or tilting. The fixing rod 42 is a component fixedly connected to the fixing collar 43 through both sides. Its function is to firmly connect the fixing collar 43 to the supporting column 33 or other parts, so as to support and stabilize the barrel 41.

[0081] Furthermore, a vertical slide groove 331 penetrating in the horizontal direction is provided in the middle of the support column 33, and the fixing rod 42 is connected to the vertical slide groove 331 through the flat head rivet 44 at its end, and can be adjusted to a fixed connection or a slidable connection according to the positioning requirements of the barrel 41. The flat head rivet 44 is used to connect one end of the fixing rod 42 to the vertical slide groove 331 of the support column 33. The end of the rivet passes through the vertical slide groove 331, realizing an adjustable connection of the barrel 41. According to needs, the connection mode of the rivet can be adjusted to a fixed connection (i.e., fixing the position of the barrel 41) or a slidable connection (i.e., the barrel 41 can slide in the vertical direction).

[0082] When the barrel 41 needs to be fixed, the fixing rod 42 is firmly connected to the vertical slide groove 331 of the support column 33 through rivets, and the barrel 41 is fixed in a specific position and cannot move up and down. When the height or position of the barrel 41 needs to be changed, the barrel 41 can slide in the vertical slide groove 331 by loosening the rivets or changing the connection method of the fixing rod 42, and then fixed after adjusting to the desired position.

[0083] In the above embodiment, the present invention enables the sample compacting cylinder 4 to be flexibly switched between fixed and slidable through the design of the fixing collar 43, the fixing rod 42, the flat head rivet 44 and the vertical slide groove 331. This design not only improves the operability and adaptability of the device, but also improves the accuracy and efficiency of adjusting the position of the cylinder body 41 during the test.

[0084] A triaxial test soil sample preparation device that can simulate the distribution of sedimentary bedding according to an embodiment of the present invention can accurately and stably complete a series of complex sample preparation operations such as bedding positioning, bedding roughening, sample preparation, sample cutting and demolding of bedding samples through the coordinated operation of a bedding positioning component, a bedding roughening component, a sample cutting component and a pressurizing component. It can accurately prepare standard triaxial test samples that can simulate the deposition thickness and angle of any soil layer, effectively meeting the urgent needs of scientific research and engineering practice for strength test samples of soil samples containing sedimentary bedding.

[0085] On the other hand, the present invention also provides a method for preparing a triaxial test soil sample based on the above-mentioned preparation device, comprising the following steps: Step 1 (sample bedding angle setting step): According to the prefabricated bedding distribution angle requirements of the sample, select a pad with a suitable angle from the bedding angle control pad 14 of the bedding angle positioning assembly and combine it with the top pressure head 131 and the bottom pressure head 132. First, align the beveled surface of the selected bedding angle control pad 14 with the beveled surface of the top pressure head 131, and nest it with the top pressure head 131 through the trapezoidal guide rail on the beveled surface of the angle control pad; then, tighten the top pressure head 131 and the bedding thickness control rod 12 through threads; finally, fix the bottom pressure head 132 to the bottom of the sample compaction cylinder 4 through the positioning card hole, and rotate the sample compaction cylinder 4 at the same time to ensure that the beveled surface of the bottom pressure head 132 is parallel to the beveled surface of the top pressure head 131. At this time, the inclination angle of the bedding angle control pad 1414 is the distribution angle of the prefabricated bedding.

[0086] Step 2 (sample bedding thickness setting step): First, pour a single portion of soil material evenly into the bottom of the sample compacting cylinder 4 equipped with a bedding angle control pad 14 to prepare for sample compaction; secondly, move the bedding thickness control rod 12 of the bedding angle positioning assembly along the top crossbeam 31 of the frame 3 to the top of the sample compacting cylinder 4, and drive the bedding thickness control rod 12 to move downward relative to the top crossbeam 31 by rotating the first operating member 11, and press it into the sample compacting cylinder 4, and then continue to drive the bedding thickness control rod 12 to continuously penetrate into the sample compacting cylinder 4 until the distance between the scale starting point of the bedding thickness control rod 12 and the bottom reference line of the slider of the frame 3 is equal to the preset bedding thickness of the sample, then the operation can be stopped. Stop the movement of the bedding thickness control rod 12, then rotate the sample compacting cylinder 4 to align the second bedding orientation positioning mark at its bottom with the first bedding orientation positioning mark on the first operating member 11, at this time, the beveled surface of the top pressure head 131 is parallel to the beveled surface of the bottom pressure head 132, finally place the support plate 63 of the pressure component 6 on the top of the hydraulic jack and align it with the center hole of the support disc 61, then start the pressure component 6 to push the support disc 61 upward, and then push the sample compacting cylinder 4 to move upward along the vertical slide groove 331 of the support column 33 of the frame 3, and realize the relative movement of the first die and the second die through the reaction force of the bedding angle positioning component to complete the compaction of the sample single layer bedding; Step 3 (scraping and roughening step of the sample surface): After the single-layer bedding of the sample is prepared, firstly, the sample compacting cylinder 4 is reset downward to the initial position along the vertical slide groove 331 of the support column 33 of the frame 3 through the pressure component 6 at the bottom of the frame 3, and the bedding thickness control rod 12 of the bedding positioning component 1 is slowly separated from the sample compacting cylinder 4 upward by rotating the first operating member 11. When it is completely separated from the top of the sample compacting cylinder 4, the bedding thickness control rod 12 is moved to one side of the top crossbeam 31 of the frame 3 through the slider mechanism 32; then, the surface roughening component 2 is moved to the top of the sample compacting cylinder 4 through the double-direction guide groove 312 of the top crossbeam 31 of the frame 3, and the rotation is driven by rotating the angle knob 233. The plate 22 rotates, and when its tilting direction is parallel to the spreading direction of the sample layer, the rotation angle knob 233 is locked by the pin 232; finally, the telescopic rod 26 is spread vertically by adjusting the self-locking universal joint 25, and the distance between the scraping top plate and the scraping bottom plate of the scraper 27 is adjusted by the bolt, and then the extension length of the scraping steel needle 274 is set according to the test requirements, and at the same time, the length of the telescopic rod 26 is adjusted so that the scraping steel needle 274 of the scraper 27 at the bottom thereof is inserted into the surface of the sample layer, and then the second operating member 21 is rotated to drive the transmission arm 24 to rotate, and then the telescopic rod 26 is driven to drive the scraper 27 to perform repeated circular scraping motions along the tilted sample layer, so that the roughening treatment of the contact layer of the sample can be completed; Step 4 (Bedding sample preparation step): After the roughening of the first layer of the sample is completed, the compaction of each layer of soil can be gradually completed according to the number of bedding layers set for the sample. First, the layer roughening component 2 needs to be reset to the initial state and initial position before step 3. The scraper 27 can be driven out of the sample compaction cylinder 4 through the telescopic rod 26 of the layer roughening component 2, and the layer roughening component 2 can be moved to the other side of the top beam 31 through the double guide groove 312 of the top beam 31 of the frame 3; secondly, according to the number of layers required for sample preparation, steps 2 and 3 are repeated continuously to complete the compaction of each layer of soil and the roughening of the layer, until the last layer of soil is compacted, and an oblique cylindrical sample with a preset bedding distribution can be obtained; finally, The sample compacting cylinder 4 is locked to the vertical slide groove 331 of the support column 33 of the frame 3 through the fixing rod 42, and the supporting disc 61 is driven downward by the pressurizing assembly 6, so that the fixing disc 53 of the cutting assembly is separated from the bottom of the sample compacting cylinder 4, and then the bottom pressure head 132 fixed to the bottom of the sample compacting cylinder 4 is taken out, and then the supporting disc 61 is moved upward again by the pressurizing assembly 6 to drive the fixing disc 53 of the cutting assembly to contact the bottom of the sample compacting cylinder 4, and then the fixing disc 53 is tightened and fixed to the bottom of the sample compacting cylinder 4 through the threaded bayonet, so as to prepare for sample cutting; Step 5 (bedding sample cutting step): First, move the sample compacting cylinder 4 downward along the vertical slide groove 331 of the support column 33 of the frame 3, so that the bedding top pressure head 131 is separated from the sample surface. When the bottom of the top pressure head 131 is just separated from the top of the sample compacting cylinder 4, the movement of the sample compacting cylinder 4 can be stopped, and the first operating member 11 is rotated to drive the bedding thickness control rod 12 to move downward and press into the sample compacting cylinder 4, so that it is in close contact with the top surface of the sample again; secondly, start the pressurizing assembly 6 to drive the sample compacting cylinder 4 along the frame 3 to press the sample top surface 131. The rack 3 moves upward, and then cooperates with the bedding thickness control rod 12 to slowly remove the sample from the bottom of the sample compacting cylinder 4 through the reaction force. When the sample compacting cylinder 4 is in close contact with the slider mechanism 32 of the top crossbeam 31 of the rack 3, the oblique cylindrical surface of the sample bottom is also completely removed from the bottom of the sample compacting cylinder 4, and then the rotating disk 51 of the sample cutting assembly 5 is driven to rotate through the third operating member 55, thereby driving the conical blade 521 of the cutting disc 52 to rotate synchronously. The conical blades 521 rotate synchronously in the process of centripetal rotation. The sample is continuously cut radially, so that the sample cutting assembly 5 can radially cut the beveled cylinder at the bottom of the bedding sample; finally, after the beveled cylinder at the bottom of the bedding sample is flattened, the first operating member 11 is rotated to drive the bedding thickness control rod 12 to move upward to make it escape from the sample compacting cylinder 4 again, and the slider mechanism 32 is used to move it to one side along the top crossbeam 31 of the frame 3, and at the same time, the sample pushing rod 64 is passed through the center of the supporting disc 61 and threadedly connected with the hydraulic jack, and the top of the sample pushing rod 64 is made to contact the sample at the bottom of the sample compacting cylinder 4, and then the hydraulic jack of the pressurizing assembly 6 is started to drive the sample pushing rod 64 to move upward, so that the sample can be slowly escaped upward along the sample compacting cylinder 4, and when the beveled cylindrical surface at the top of the sample just escapes from the top of the sample compacting cylinder 4, the sample cutting assembly 5 fixed to the top of the sample compacting cylinder 4 is used to radially cut the beveled cylinder at the top of the sample, and the cutting steps and process are consistent with the cutting operation at the bottom of the sample, and after the beveled cylinder at the top of the sample is completely flattened, the cutting work of the bedding sample is completed.

[0087] Step 6 (bedding sample demoulding step): After completing the cutting of the bedding sample, continue to drive the sample pushing rod 64 fixedly connected to the hydraulic jack of the pressurizing assembly 6 to move upward, so that it pushes the sample through the center hole of the support disc 61 and slowly removes it from the top of the compaction cylinder. When the bedding sample is completely removed from the top of the sample compaction cylinder 4, the bedding sample demoulding work is completed, and a standard triaxial test sample with a preset bedding structure is obtained.

[0088] The present invention provides a triaxial test soil sample preparation device and preparation method which can simulate the distribution of sedimentary bedding. The bedding positioning component can meet the setting requirements for preparing samples with any number of bedding layers and any bedding angle. The layer roughening component can realize automatic fine scraping of the sample contact layer, thereby improving the stability of the sample contact layer. The sample cutting component can realize automatic and precise radial cutting of the bedding sample, thereby overcoming the disadvantages of the bedding sample being fragile and difficult to cut, thereby improving the sample quality of the bedding sample. The device can stably complete a series of complex preparation processes such as bedding positioning, layer roughening, sample preparation, sample cutting and demolding of the bedding sample through the coordinated operation of the bedding positioning component, the layer roughening component, the sample cutting component and the pressurizing component. Only one device can efficiently prepare standard triaxial test samples which can simulate any soil layer deposition thickness and angle. The device is integrated and automated, simple to operate and stable in operation, thereby greatly improving the preparation efficiency and finished product quality of the bedding sample.

[0089] In the present invention, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with features of other embodiments or replace features of other embodiments.

[0090] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the embodiments of the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution, characterized in that: The preparation device comprises: a frame (3), a sample compacting cylinder (4), a layer positioning component (1), and a pressurizing component (6); The sample compacting cylinder (4) comprises a cylinder body (41), wherein the cylinder body (41) has a cavity which is used to accommodate the sample and is arranged through the cylinder body; The bedding positioning assembly (1) comprises a bedding thickness control rod (12), a first die and a second die, wherein the first die and the second die have extrusion surfaces that match each other, the extrusion surfaces of the two dies are used to directly contact the sample to extrude the bedding structure, the extrusion surfaces of the two dies are parallel or non-parallel to each other, and the extrusion surfaces are set to be smooth or rough, flat or curved; the first die and the second die at least include a plurality of replaceable dies with different inclination angles, which are used to control different bedding angles; When the preparation device is in a state of pressing the sample bedding, the bedding thickness control rod (12) and the pressurizing assembly (6) are respectively mounted on both sides of the barrel (41) and fixed to the frame (3), the first pressing die is fixedly mounted at the end of the bedding thickness control rod (12), the second pressing die is mounted at one end of the barrel (41) facing the pressurizing assembly (6), or the second pressing die is fixedly mounted at the movable end of the pressurizing assembly (6), and at least one of the first pressing die and the second pressing die can extend into the barrel (41).

2. The triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution according to claim 1, characterized in that: The sample compacting cylinder (4) is arranged in a vertical direction, the first compression mold comprises a top compression head (131), the second compression mold comprises a bottom compression head (132), and the first compression mold and the second compression mold both further comprise a matching bedding angle control pad (14); The upper end of the top pressure head (131) has a threaded hole or a threaded column for threaded connection with the bottom end of the bedding thickness control rod (12); The lower end of the bottom pressure head (132) has a cylindrical section, and the cylindrical section is used to connect with the lower end of the sample compacting cylinder (4); The lower end of the top pressure head (131) and the upper end of the bottom pressure head (132) both have a pad connection portion, and the pad connection portion comprises a mounting inclined surface and a slot structure; The bedding angle control pad (14) has a pressure head connection portion at one end facing the pad connection portion, the pressure head connection portion comprising another inclined surface of the same shape as the installation inclined surface of the pressure head, and a trapezoidal guide rail protrusion matching the slot structure; The bottom pressure head (132) and the top pressure head (131) are designed as a common mounting seat for the bedding angle control pad (14) having different inclination angles; The bedding angle control pad (14) comprises a plurality of replaceable modules with different inclination angles, all of which are designed as rigid beveled cone structures.

3. The triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution according to claim 1, characterized in that: The frame (3) is in a frame structure, comprising a top crossbeam (31), a slider mechanism (32), support columns (33) arranged on both sides, and a bottom base (34); the support columns (33) arranged on both sides are fixedly arranged on the bottom base (34), and the top crossbeam (31) is fixedly arranged on the two support columns (33); The middle portion of the top crossbeam (31) has a through slot (311) extending through the top crossbeam (31) in a vertical direction. The slider mechanism (32) is installed in the through slot (311). The slider mechanism (32) is configured to be able to move horizontally along the extension direction of the through slot (311).

4. The triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution according to claim 3, characterized in that: The bedding thickness control rod (12) of the bedding positioning assembly (1) has an external thread for being threadedly connected to a slider of the slider mechanism (32), so that the bedding thickness control rod (12) is installed in the through groove (311) through the slider mechanism (32); The slider mechanism (32) further comprises a locking member, which is used to lock the position of the slider mechanism (32) and the layer thickness control rod (12); The bedding thickness control rod (12) is also provided with a length scale distributed along its axial direction, which is used to determine the depth of the bedding thickness control rod (12) below the slider in combination with the bottom reference surface of the slider, so as to adjust the bedding thickness of the sample; The bedding positioning assembly (1) further comprises a first operating member (11) arranged on the top of the bedding thickness control rod (12) and used for controlling the rotation of the bedding thickness control rod (12); The first operating member (11) or the bedding thickness control rod (12) is provided with a first bedding orientation positioning mark for indicating the inclination orientation of the extrusion surface of the first die; the bottom of the barrel (41) is provided with a second bedding orientation positioning mark for indicating the inclination orientation of the extrusion surface of the second die.

5. The triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution according to claim 3, characterized in that: The preparation device further comprises a layer roughening assembly (2), wherein the layer roughening assembly (2) comprises a second operating member (21), a rotating plate (22), an angle adjuster (23), a transmission arm (24), a telescopic rod (26) and a scraper (27); The surface roughening assembly (2) is used to be installed in the through groove (311) of the top crossbeam (31); the top crossbeam (31) is provided with horizontally penetrating two-way guide grooves (312) on both sides of its through groove (311); the width of the rotating plate (22) does not exceed the width of the through groove (311); the rotating plate (22) has short shafts on both sides for being installed in the two-way guide groove (312); the short shaft on one side of the rotating plate (22) extends out of the two-way guide groove (312) for installing the angle adjuster (23); the rotating plate (22) can move in the two-way guide groove (312) via the short shaft to adjust its horizontal position relative to the sample compacting cylinder (4) and the sample; The second operating member (21) is mounted above the rotating plate (22); the transmission arm (24) passes through the rotating plate (22) and is mounted below the rotating plate (22); one end of the transmission arm (24) is connected to the second operating member (21); the other end of the transmission arm (24) is connected to the telescopic rod (26) via a self-locking universal joint (25); the hair scraper (27) is mounted at the bottom end of the telescopic rod (26); the rotating plate (22) is used to control the tilt angles of the second operating member (21), the transmission arm (24), the telescopic rod (26) and the hair scraper (27); The angle adjuster (23) comprises a knob chassis (231) and an angle knob (233); the surface of the knob chassis (231) has an angle scale, and the angle knob (233) has an angle reference line; the angle adjuster (23) drives the short axis to rotate by rotating the angle knob (233), thereby driving the rotating plate (22) to rotate so that the rotating plate (22) is consistent with the inclination angle of the sample layer, and the rotation angle indicated by the angle reference line of the angle knob (233) is configured so that the rotating plate (22) is parallel to the sample layer; The second operating member (21) is used to control the transmission arm (24) to rotate along its axis, so as to drive the telescopic rod (26) and the scraper (27) to perform circular motion, so that the scraper (27) can perform a scraping operation on the inclined surface of the sample; The scraper (27) comprises a scraper bottom plate (272), a scraper top plate (271), a scraper steel needle (274) and a height-adjustable connecting piece (273); wherein the scraper bottom plate (272) is fixedly mounted on the bottom end of the telescopic rod (26); the scraper top plate (271) is spaced apart from and parallel to the scraper bottom plate (272) via the height-adjustable connecting piece (273); the scraper steel needle (274) is fixedly mounted on the lower end surface of the scraper bottom plate (272) and passes through a plurality of fine holes of the scraper top plate (271); the height-adjustable connecting piece (273) is used to control the distance between the scraper bottom plate (272) and the scraper top plate (271) so as to change the protruding length of the scraper steel needle (274) at the scraper top plate (271).

6. The triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution according to claim 3, characterized in that: The preparation device further comprises a sample cutting assembly (5), wherein the sample cutting assembly (5) comprises an upper cutting group for cutting the upper end of the sample; The upper cutting group comprises a rotating disk (51), a cutting disc (52), a fixed disk (53) and a third operating member (55); wherein the cutting disc (52) is sandwiched between the rotating disk (51) and the fixed disk (53); an internal threaded hole is provided at the center of the fixed disk (53) for being threadedly connected to the upper end of the sample compacting cylinder (4), thereby achieving fixed installation of the fixed disk (53); The cutting blade disc (52) comprises a plurality of groups of conical blades (521) which are centrally symmetrical, and the inner long sides of the conical blades (521) have cutting edges; A plurality of centripetal rotation guide grooves (531) extending along an oblique line are provided on a side of the fixed disk (53) facing the cutting blade disk (52); a rectangular protruding guide shaft is provided on the end surface of each conical blade (521) facing the fixed disk (53); the length of the centripetal rotation guide groove (531) is greater than the length of the rectangular protruding guide shaft, and the two have the same width; A strip groove (522) is provided on one side of the conical blade (521) facing the rotating disk (51), and a circular protruding guide shaft (511) is provided on one side of the rotating disk (51) facing the cutting blade disk (52), wherein the diameter of the circular protruding guide shaft (511) is the same as the width of the strip groove (522); The rotating disk (51) is provided with at least two arc-shaped guide grooves (512) close to the outer edge thereof; the rotating disk (51) is inserted into the arc-shaped guide grooves (512) via at least two connecting pieces fixed to the fixed disk (53), thereby realizing a rotatable connection with the fixed disk (53); the two sides of the arc-shaped guide grooves (512) in the horizontal direction are used to abut against the connecting pieces during the cutting process, thereby driving the cutting disc (52) to rotate forward or reversely; The rotating disk (51) has a central opening, the diameter of which is larger than the outer diameter of the sample compacting cylinder (4). The third operating member (55) is connected to the rotating disk (51), so that the rotating disk (51) can be driven by the third operating member (55) to rotate forward or reverse, thereby driving the various conical blades (521) of the cutting disc (52) to rotate centripetally along the centripetal rotating guide groove (531). During the centripetal rotation process, the regular polygon formed by the cutting edges gradually becomes smaller, thereby cutting the upper end of the sample.

7. The triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution according to claim 6, characterized in that: The sample cutting assembly (5) further comprises a lower cutting group for cutting the lower end of the sample; the fixing plate (53) of the lower cutting group is used for threaded connection with the lower end of the sample compacting cylinder (4).

8. The triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution according to claim 7, characterized in that: The pressurizing assembly (6) comprises a supporting disc (61), a supporting rod (62), a supporting plate (63), a sample pushing column, a tension spring (65) and a lifting mechanism (66); The lifting mechanism (66) comprises any one of a hydraulic cylinder, a pneumatic cylinder and a motor drive mechanism, and is used for being fixedly mounted on the bottom base (34); The support disc (61) is installed on the top of the lifting mechanism (66) via the support plate (63), and two sides thereof are connected to the bottom base (34) via tension springs (65); The support rod (62) is mounted on the top of the support disc (61) and is used to connect with the sample cutting assembly (5) or the sample compacting cylinder (4); The sample pushing column is a columnar structure of a certain length, the outer diameter of which is not greater than the inner diameter of the sample compacting cylinder (4), and is used to be lifted by the lifting mechanism (66) into the sample compacting cylinder (4) and push the sample out.

9. The triaxial test soil sample preparation device capable of simulating sedimentary bedding distribution according to claim 3, characterized in that: The sample compacting cylinder (4) further comprises a fixing rod (42), a fixing collar (43) and a flat head rivet (44); The fixing collar (43) is used to be sleeved in the annular groove in the middle of the barrel (41), and two sides of the fixing collar (43) are fixedly connected to the fixing rod (42); A vertical slide groove (331) is provided in the middle of the support column (33) and runs through in the horizontal direction. The fixing rod (42) is connected to the vertical slide groove (331) via the flat head rivet (44) at its end, and can be adjusted to a fixed connection or a slidable connection according to the positioning requirements of the barrel (41).

10. A method for preparing a triaxial test soil sample capable of simulating sedimentary bedding distribution, the preparation method being implemented based on a preparation device as claimed in any one of claims 1 to 9, the method comprising: Step 1: According to the requirement of the prefabricated bedding distribution angle of the sample, a bedding angle control pad (14) of the bedding angle positioning assembly is selected to combine with the top pressure head (131) and the bottom pressure head (132); first, the beveled surface of the selected bedding angle control pad (14) is aligned with the beveled surface of the top pressure head (131), and the bedding angle control pad is nested and connected with the top pressure head (131) through the trapezoidal guide rail on the beveled surface of the bedding angle control pad; then, the top pressure head (131) and the bedding thickness control rod (12) are screwed and tightened; finally, the bottom pressure head (132) is fixed to the bottom of the sample compaction cylinder (4) through the positioning card hole, and the sample compaction cylinder (4) is rotated at the same time to ensure that the beveled surface of the bottom pressure head (132) is parallel to the beveled surface of the top pressure head (131). At this time, the inclination angle of the bedding angle control pad (14) is the distribution angle of the prefabricated bedding; Step 2: First, pour a single portion of soil material evenly into the bottom of the sample compaction cylinder (4) equipped with a bedding angle control pad (14) to prepare for sample compaction; second, move the bedding thickness control rod (12) of the bedding angle positioning assembly along the top crossbeam (31) of the frame (3) to the top of the sample compaction cylinder (4), and drive the bedding thickness control rod (12) to move downward relative to the top crossbeam (31) by rotating the first operating member (11) and press it into the sample compaction cylinder (4), and then continue to drive the bedding thickness control rod (12) to continuously penetrate into the sample compaction cylinder (4) until the distance between the scale starting point of the bedding thickness control rod (12) and the bottom reference line of the slider of the frame (3) is equal to the preset bedding thickness of the sample, then the bedding thickness control rod can be stopped. The rod (12) is moved, and the sample compacting cylinder (4) is then rotated so that the second bedding orientation positioning mark at the bottom thereof is aligned with the first bedding orientation positioning mark on the first operating member (11). At this time, the beveled surface of the top pressure head (131) is parallel to the beveled surface of the bottom pressure head (132). Finally, the support plate (63) of the pressure component (6) is placed on the top of the hydraulic jack and aligned with the center hole of the support disc (61). The pressure component (6) is then started to push the support disc (61) upward, thereby pushing the sample compacting cylinder (4) upward along the vertical slide groove (331) of the support column (33) of the frame (3). The relative movement of the first die and the second die is achieved through the reaction force of the bedding angle positioning component, thereby completing the compaction of the single-layer bedding of the sample; Step 3: After the single-layer bedding of the sample is prepared, first, the pressure component (6) at the bottom of the frame (3) is used to reset the sample compacting cylinder (4) downward along the vertical slide groove (331) of the support column (33) of the frame (3) to the initial position, and the bedding thickness control rod (12) of the bedding positioning component (1) is slowly disengaged from the sample compacting cylinder (4) upward by rotating the first operating member (11). When it is completely out of the top of the sample compacting cylinder (4), the bedding thickness control rod (12) is moved to one side of the top crossbeam (31) of the frame (3) through the slider mechanism (32); then, the layer roughening component (2) is moved to the top of the sample compacting cylinder (4) through the double-direction guide groove (312) of the top crossbeam (31) of the frame (3), and the angle knob (233) is rotated. The rotating plate (22) is driven to rotate, and when its tilting direction is parallel to the spreading direction of the sample layer, the rotation angle knob (233) is locked by a pin; finally, the telescopic rod (26) is vertically spread by adjusting the self-locking universal joint (25), and the distance between the scraping top plate and the scraping bottom plate of the scraper (27) is adjusted by a bolt, and then the extension length of the scraping steel needle (274) is set according to the test requirements, and at the same time, the length of the telescopic rod (26) is adjusted so that the scraping steel needle (274) of the scraper (27) at the bottom thereof is inserted into the surface of the sample layer, and then the second operating member (21) is rotated to drive the transmission arm (24) to rotate, and then the telescopic rod (26) is driven to drive the scraper (27) to perform repeated circular scraping motions along the tilted sample layer, thereby completing the roughening treatment of the contact layer of the sample; Step 4: After the roughening of the first layer of the sample is completed, the compaction of each layer of soil can be gradually completed according to the number of layers set for the sample. First, the roughening component (2) needs to be reset to the initial state and initial position before step 3. The scraper (27) can be driven to detach from the sample compaction cylinder (4) through the telescopic rod (26) of the roughening component (2), and the roughening component (2) can be moved to the other side of the top beam (31) through the double guide groove (312) of the top beam (31) of the frame (3). Secondly, according to the number of layers required for sample preparation, steps 2 and 3 are repeated continuously to complete the compaction of each layer of soil and the roughening of the layer until the last layer of soil is compacted. Finally, the sample compacting cylinder (4) is locked to the vertical slide groove (331) of the supporting column (33) of the frame (3) through the fixing rod (42), and the supporting disc (61) is driven downward by the pressurizing assembly (6), so that the fixing disc (53) of the cutting assembly is separated from the bottom of the sample compacting cylinder (4), and then the bottom pressure head (132) fixed to the bottom of the sample compacting cylinder (4) is taken out, and then the supporting disc (61) is moved upward again by the pressurizing assembly (6) to drive the fixing disc (53) of the cutting assembly to contact the bottom of the sample compacting cylinder (4), and then the fixing disc (53) is tightened and fixed to the bottom of the sample compacting cylinder (4) through the threaded bayonet, so as to prepare for sample cutting; Step 5: First, the sample compacting cylinder (4) is moved downward along the vertical slide groove (331) of the support column (33) of the frame (3) to separate the bedding top pressure head (131) from the sample surface. When the bottom of the top pressure head (131) just separates from the top of the sample compacting cylinder (4), the movement of the sample compacting cylinder (4) is stopped, and the first operating member (11) is rotated to drive the bedding thickness control rod (12) to move downward and press into the sample compacting cylinder (4) so ​​that it is in close contact with the top surface of the sample again. Secondly, the pressurizing assembly (6) is started to drive the sample compacting cylinder (4) along the frame (3). The sample is moved upward, thereby cooperating with the bedding thickness control rod (12) to slowly disengage the sample from the bottom of the sample compacting cylinder (4) through the reaction force. When the sample compacting cylinder (4) is in close contact with the slider mechanism (32) of the top crossbeam (31) of the frame (3), the oblique cylindrical surface at the bottom of the sample is also completely disengaged from the bottom of the sample compacting cylinder (4). Then, the rotating disk (51) of the sample cutting assembly (5) is driven to rotate through the third operating member (55), thereby driving the conical blade (521) of the cutting disc (52) to rotate synchronously. The centripetal rotation process of the multiple groups of conical blades (521) causes The cutting edge of the blade continuously cuts the sample in the radial direction, thereby realizing radial cutting of the beveled cylinder at the bottom of the bedding sample by the sample cutting assembly (5); finally, after the beveled cylinder at the bottom of the bedding sample is flattened, the first operating member (11) is rotated to drive the bedding thickness control rod (12) to move upward so that it can be disengaged from the sample compacting cylinder (4) again, and the slider mechanism (32) is used to move it to one side along the top crossbeam (31) of the frame (3), and at the same time, the sample pushing rod (64) is passed through the center of the support disc (61) and is threadedly connected to the hydraulic jack, and the top of the sample pushing rod (64) is aligned with the sample. The sample is in contact with the sample at the bottom of the sample compacting cylinder (4), and the hydraulic jack of the pressurizing assembly (6) is then started to drive the sample push rod (64) to move upward, so that the sample can be slowly ejected upward along the sample compacting cylinder (4). When the beveled cylindrical surface at the top of the sample just comes out of the top of the sample compacting cylinder (4), the sample is ejected. The beveled cylindrical body at the top of the sample is radially cut by the sample cutting assembly (5) fixed to the top of the sample compacting cylinder (4). The cutting steps and process are the same as the cutting operation at the bottom of the sample. When the beveled cylindrical body at the top of the sample is completely flattened, the cutting work of the bedding sample is completed. Step 6: After the bedding sample is cut, the sample push rod (64) fixedly connected to the hydraulic jack of the pressurizing assembly (6) is driven upward to push the sample through the center hole of the support disc (61) and slowly release it from the top of the compacting cylinder. When the bedding sample is completely released from the top of the sample compacting cylinder (4), the demoulding work of the bedding sample is completed, and a standard triaxial test sample with a preset bedding structure is obtained.

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