Assembly type sample box in-situ sample preparation device with vertical contact surface and sample preparation method

Abstract

The invention discloses a vertical contact surface assembly type sample box in-situ sample preparation device and method, the device comprises a reaction frame body, a rigid sample box, a horizontal fixing module and a vertical pressurizing module, the rigid sample box is movably arranged on the inner side of the reaction frame body, and the rigid sample box comprises an n-shaped frame, a lower pin and a convex bottom plate. The reaction frame body is constructed, and the vertical servo hydraulic loading device and the horizontal fixing device are additionally arranged on the reaction frame body, so that a rigid sample box is stably pushed, an n-shaped frame can vertically cut into a structural body, plugging is carried out under the cooperation of a convex bottom plate and a loading plate, a frame-shaped sample box is formed, and a sample is prepared; the cut-in sample is formed on the inner side of the closed frame-shaped sample box, so that the vertical shearing surface requirement of the in-situ vertical contact surface shearing test is met. The device solves the problem that the sample is difficult to cut and repair due to the fact that the vertical height of the sample is obviously larger than the horizontal width.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rock-soil shear, in particular to an in-situ sample preparation device and method for an assembled sample box with vertical contact surface. BACKGROUND

[0002] In the research of geotechnical engineering, geomechanics and structural interface mechanics, the shear strength characteristics of the soil-structure contact surface (such as the anti-seepage wall-soil interface and the pile-soil interface) are the core parameters for evaluating the safety of the project. Traditional shear test equipment (such as the direct shear apparatus and the ring shear apparatus) usually adopts a horizontal shear mode, and the sample preparation and loading direction are designed based on the horizontal shear surface. However, in actual engineering, there are scenarios such as the pile-soil contact surface perpendicular to the ground. The normal height of the shear sample is usually only about half of the size in the shear direction, and the traditional shear sample can be directly cut and trimmed in-situ. The sample is only subjected to vertical gravity, and there is no horizontal load. After the sample preparation task is completed, the sample box can be directly fitted outside the sample from top to bottom using the gravity of the sample box, which has little effect on the sample. However, for the preparation of vertical shear test, compared with the traditional horizontal shear test, there are three differences as follows.

[0003] (1) Since the shear surface is vertical, the shear height of the sample is significantly greater than the normal size, and the vertical contact surface is also a weak structural surface of the sample, which further increases the difficulty of ensuring the integrity of the sample during cutting and trimming.

[0004] (2) The bottom surface of the sample is not the shear surface of the test, and the contact between the sample and the sample box needs to be completed during the sample preparation, which makes the sample preparation method of the vertical shear test different from that of the traditional horizontal shear test.

[0005] (3) The sample is affected by gravity. In the traditional horizontal shear test, the sample is first cut and trimmed, and then the sample box is vertically pushed into the sample box using the gravity of the sample box to make the sample vertically enter the sample box, which is completed. However, in the sample preparation of the vertical shear test, not only the pushing force needs to be applied to the sample box to overcome the friction between the sample box and the soil sample, but also the bottom plate of the sample box needs to be cut into the soil to make the bottom surface of the sample directly contact with the sample box.

[0006] Since the existing shear test equipment cannot meet the sample preparation requirements of the vertical shear test, it is necessary to invent an in-situ sample preparation device and method for an assembled sample box with vertical contact surface to solve the above problems. SUMMARY

[0007] The application aims to provide an in-situ sample preparation device and method for an assembled vertical contact sample box.

[0008] To achieve the above-mentioned purpose, the application provides the following technical scheme.

[0009] The in-situ sample preparation device for an assembled vertical contact sample box comprises a counterforce frame body, a rigid sample box, a horizontal fixing module and a vertical pressing module, wherein the rigid sample box is movably arranged on the inner side of the counterforce frame body, the rigid sample box comprises a H-shaped frame, lower pins and a convex bottom plate, the two lower pins are symmetrically arranged on the bottom of the two vertical side plates of the H-shaped frame, the top of the H-shaped frame is detachably connected with the upper top beam of the sample box through bolts, and the convex bottom plate is detachably arranged between the bottoms of the two vertical side plates of the H-shaped frame, and the rear end of the H-shaped frame is attached to a structure.

[0010] The counterforce frame body is arranged on one side of the structure and is arranged outside the geological body.

[0011] The horizontal fixing module is transversely arranged on the inner side of the counterforce frame body and is slidably connected with the vertical surface of the counterforce frame body, and the horizontal fixing module is used for driving the loading plate attached to the inner wall of the H-shaped frame.

[0012] The vertical pressing module is vertically arranged on the top of the counterforce frame body, the output end of the vertical pressing module is anchoringly connected with the upper top beam of the sample box, so that the H-shaped frame is cut into the geological body and the soil sample is prepared.

[0013] As a preferred scheme of the application, the counterforce frame body comprises a counterforce frame base, an I-beam upper frame, an I-beam lower frame and a middle column with a slide rail, the number of the counterforce frame base is four, the four counterforce frame bases are arranged in a rectangular array on the outer wall of the structure and are fixedly connected with the structure through expansion bolts, the two counterforce frame bases on the upper side are each anchoringly provided with a ribbed upper cross beam, the two counterforce frame bases on the lower side are each anchoringly provided with a ribbed lower cross beam, the two ribbed upper cross beams are connected with the upper rib plate through locking bolts at the ends away from the counterforce frame bases, and the two ribbed upper cross beams and the corresponding two counterforce frame bases jointly form the I-beam upper frame; the two ribbed lower cross beams are connected with the lower rib plate through locking bolts at the ends away from the counterforce frame bases, and the two ribbed lower cross beams and the corresponding two counterforce frame bases jointly form the I-beam lower frame; and the middle column is anchoringly arranged between the I-beam upper frame and the I-beam lower frame.

[0014] As a preferred scheme of the present application, the vertical pressing module comprises a lifting rod, a loading top beam, a first load sensor, a vertical hydraulic actuator and a vertical base, wherein the vertical hydraulic actuator is fixedly connected with the I-shaped upper frame through the vertical base at the bottom, the first load sensor and the loading top beam are bolted on the output end of the vertical hydraulic actuator from bottom to top, the lifting rod is connected on the loading top beam, and the bottom end of the lifting rod is anchoringly connected with the upper top beam of the sample box.

[0015] As a preferred scheme of the present application, the horizontal fixing module comprises a horizontal base, a horizontal hydraulic actuator, a second load sensor and a loading plate, the horizontal hydraulic actuator is slidingly fitted on the slide rail through the horizontal base, the loading plate and the second load sensor are bolted on the output end of the hydraulic actuator in sequence from left to right, and the loading plate is movable at the front end of the L-shaped frame.

[0016] As a preferred scheme of the present application, a plurality of uniformly distributed rollers are rotatably arranged at one end of the L-shaped frame close to the structure, and the rollers are detachably connected with the L-shaped frame.

[0017] As a preferred scheme of the present application, the vertical side plates on both sides of the L-shaped frame are distributed in parallel, and the length of the convex bottom plate is equal to the spacing between the two vertical side plates of the L-shaped frame.

[0018] The lower pin is composed of an L-shaped angle steel and a cutter plate, wherein the L-shaped angle steel is attached to the outside of the bottom end of the vertical side plate, and the cutter plate is integrally welded to the bottom of one end of the L-shaped angle steel, the cutter plate is made of a thin steel plate, and the opposite sides of the two cutter plates are flush with the opposite side walls of the two vertical side plates.

[0019] As a preferred scheme of the present application, the convex bottom plate is integrally provided with a plug-in plate on both sides, a gap is reserved between the L-shaped angle steel and the bottom end of the vertical side plate of the L-shaped frame, forming a lower foot groove matching the thickness of the plug-in plate, the convex bottom plate and the L-shaped frame are slidingly fitted through the plug-in plate and the lower foot groove, and the end of the convex bottom plate is wedge-shaped.

[0020] The L-shaped angle steel is attached to the outside of the bottom end of the L-shaped frame and is fixedly connected with the side wall of the vertical side plate of the L-shaped frame through the second fixing screw, the L-shaped angle steel and the side wall of the vertical side plate of the L-shaped frame are both penetrated by a through hole, the convex bottom plate is provided with a pin hole matching the through hole on both sides, and a pin shaft is jointly inserted into the through hole and the pin hole after corresponding, the bottom of the L-shaped angle steel and the bottom end of the L-shaped frame are connected by a first fixing screw, and the first fixing screw penetrates the plug-in plate.

[0021] As a preferred scheme of the present application, the connecting end of the first load sensor and the second load sensor is electrically connected with a control host through a data line, and the connecting end of the control host is electrically connected with an operation terminal through a data line, the control host is internally provided with a servo controller and a data acquisition system, the data acquisition system acquires feedback data of the first load sensor and the second load sensor and transmits the feedback data to the servo controller for analysis and processing, the vertical hydraulic actuator and the horizontal hydraulic actuator are connected with a hydraulic power unit through independently arranged oil pipes, and an electro-hydraulic servo valve is arranged on each of the two oil pipes, and the electro-hydraulic servo valve is electrically connected with the control host through a data line.

[0022] The present application also provides a vertical shear sample preparation method, which uses the in-situ sample preparation device of the assembled vertical contact surface sample box and comprises the following steps:

[0023] S1, counterforce frame body positioning and installation fixing: four sets of installation points are marked on the structure body on one side of the geological body, the counterforce frame base at the end of the upper I-shaped frame and the lower I-shaped frame is fixed on the geological body by using expansion bolts at each installation point position, and the middle column with a slide rail is anchored between the upper ribbed cross beam and the lower ribbed cross beam to provide a counterforce support for sample preparation;

[0024] S2, vertical pressure module is added: fixed on the top of the upper I-shaped frame by using screws; connect the vertical base, and fix the cylinder end of the vertical hydraulic actuator vertically upwards after arranging the vertical hydraulic actuator vertically upwards, and sequentially connect the first load sensor and the loading top beam on the output shaft of the vertical hydraulic actuator from bottom to top by using bolts, and then connect the lifting rod extending to the bottom of the upper I-shaped frame on the loading top beam to form a vertical servo hydraulic loading device;

[0025] S3, horizontal fixing module is added: set a horizontal base in the slide rail and limit it by using screws, fix the cylinder end of the horizontal hydraulic actuator on one side of the horizontal base, connect the loading plate to the output end of the horizontal hydraulic actuator, and install the second load sensor outside the output shaft of the horizontal hydraulic actuator and between the loading plate and the cylinder end to form a horizontal fixing device;

[0026] S4, rigid sample box is arranged: the open side of one end of the H-shaped frame is attached to the structure body and can slide flexibly, the distance between the rigid sample box and the structure body is controlled by selecting the size of the roller, the output end of the vertical hydraulic actuator is adjusted to extend to the length that the bottom end of the lifting rod contacts the top beam of the sample box and is fixed, and the H-shaped frame is in a transmission relationship; at the same time, the position of the horizontal fixing device is adjusted so that the loading plate corresponds to the lateral opening of the H-shaped frame and contacts the plugging to form a frame-shaped sample box;

[0027] S5, the assembled sample preparation method cuts into the sample preparation: after the frame-shaped sample box is in place, the cutter plate is suspended above the geological body at this time, and the convex bottom plate is in the pulled-out state, the vertical hydraulic actuator output end is controlled to stretch and retract, driving the lifting rod to press down the H-shaped frame, under the action of the cutter plate and the pressure, the H-shaped frame cuts into the geological body, after the frame-shaped sample box is completely filled with soil, the convex bottom plate is inserted into the corresponding lower groove on both sides, the geological body is cut off from the inside bottom end of the H-shaped frame, the excess geological body is cut off along the side edge of the H-shaped frame, and the edge is processed, and the soil on both sides of the H-shaped frame is excavated, and the sample is formed in the inside of the closed frame-shaped sample box.

[0028] As a preferred scheme of the present application, in the sample preparation process, the control function of the vertical hydraulic actuator servo loading is ensured, the net height H of the lower edge of the I-shaped upper frame and the top surface of the geological body and the downward movement amount s of the rigid sample box satisfy the following formula:

[0029] H0+H1+H2+ΔH≤H

[0030] s=H-H1-d+Δd

[0031] Wherein, H0 is the height of the H-shaped frame, H1 is the height of the upper top beam of the sample box, H2 is the length of the cutter plate extending out of the H-shaped frame, ΔH is the surplus value of the net height H during installation, d is the thickness of the top plate of the H-shaped frame, and Δd is the sample top sample preparation compression deformation amount.

[0032] In the above technical scheme, the present application provides technical effects and advantages:

[0033] 1. By constructing the counterforce support body, providing support force, installing vertical servo hydraulic loading device and horizontal fixing device on the counterforce support body, stably advancing the rigid sample box, enabling the H-shaped frame to vertically cut into the structure, and enabling the convex bottom plate and the loading plate to cooperate to block, forming the frame-shaped sample box, preparing the sample, and forming the sample inside the closed frame-shaped sample box after cutting, meeting the vertical shear surface requirement of the in-situ vertical contact surface shear test, and overcoming the problem that the sample is difficult to cut and trim due to the vertical height being obviously larger than the horizontal width size.

[0034] 2. Through modular design, the combination components of the rigid sample box are convenient to dock, can meet the test and disassembly functions, meet the sample preparation requirements of different positions, the simple counterforce support body support structure reduces the weight of the support, improves the counterforce bearing capacity, and also considers the detachability, the sample preparation and shear process use the same counterforce support, and the sample preparation equipment components include the components required in the shear process, thereby increasing the convenience of the test. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description only represent some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art based on these drawings.

[0036] Figure 1 The schematic diagram of the initial installation state of the in-situ vertical shear sample preparation device provided by the present application.

[0037] Figure 2 The schematic diagram of the downward sample cutting state of the in-situ vertical shear sample preparation device provided by the present application.

[0038] Figure 3 The schematic diagram of the convex bottom plate cutting-in state of the in-situ vertical shear sample preparation device provided by the present application.

[0039] Figure 4 The combination relationship demonstration diagram of the rigid sample box and the convex bottom plate in the present application.

[0040] Figure 5 The corresponding structure schematic diagram of the structure combination shown in the present application. Figure 4

[0041] The right view of the structure shown in the present application. Figure 6 Figure 5 The combination structure schematic diagram of the loading plate and the L-shaped frame in the present application.

[0042] Figure 7 The side view of the convex bottom plate in the present application.

[0043] Figure 8 The sample preparation length schematic diagram of the in-situ vertical shear assembly type sample box provided by the present application.

[0044] Figure 9 Explanation of reference signs:

[0045] Explanation of reference signs:

[0046] ​1. Lifting rod; 2. Loading top beam; 3. First load cell; 4. Vertical hydraulic actuator; 5. Vertical base; 6. I-beam upper frame; 7. Ribbed upper crossbeam; 8. Central column; 9. Slide rail; 10. Horizontal base; 11. Horizontal hydraulic actuator; 12. Second load cell; 13. Geological body; 14. Loading plate; 15. Rigid sample box; 16. Ribbed lower crossbeam; 17. I-beam lower frame; 18. Control host; 19. Operating terminal; 20. Data cable; 21. Oil pipe; 22. Roller; 23. Structure; 24. Locking bolt; 25. Expansion bolt; 26. Sample box upper top beam; 27. Convex base plate; 28. Lower insert; 29. ​​Pin shaft; 30. Electric push rod; 31. Reaction frame base; 32. First fixing screw; 33. U-shaped frame; 34. Second fixing screw. Detailed Implementation

[0047] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0048] This invention provides, for example Figures 1-8 The above describes an in-situ sample preparation device for a vertically contacting prefabricated sample box, comprising a reaction frame body, a rigid sample box 15, a horizontal fixing module, and a vertical pressurizing module. The rigid sample box 15 is movably disposed inside the reaction frame body. The rigid sample box 15 includes a U-shaped frame 33, lower inserts 28, and a convex base plate 27. The two lower inserts 28 are axially symmetrically distributed at the bottom of the two vertical side plates of the U-shaped frame 33. The top of the U-shaped frame 33 is detachably connected to the upper top beam 26 of the sample box via bolts 24. The convex base plate 27 is detachably installed between the bottom of the two vertical side plates of the U-shaped frame 33. The rear end of the U-shaped frame 33 is attached to the structure 23. In this embodiment, the length of the upper top beam 26 of the sample box is greater than the length of the U-shaped frame 33, so that the upper top beam 26 of the sample box has an extension section reserved on both sides of the U-shaped frame 33.

[0049] The reaction frame body is installed on one side of the structure 23 and is erected on the outside of the geological body 13;

[0050] The horizontal fixing module is horizontally positioned inside the reaction frame body and slides on the vertical surface of the reaction frame body. The horizontal fixing module is used to drive the loading plate 14 that is in contact with the inner wall of the U-shaped frame 33. When the horizontal fixing module drives the loading plate 14 to move in the horizontal direction, it plays a role in limiting the displacement of the side plate of the U-shaped frame 33.

[0051] The vertical pressurization module is vertically mounted on the top of the reaction frame body. The output end of the vertical pressurization module is anchored to the top beam 26 of the sample box, allowing the U-shaped frame 33 to cut into the geological body 13 and prepare soil samples. By lifting the top beam 26 of the sample box at the top of the U-shaped frame 33 using the vertical pressurization module, the displacement of the rigid sample box 15 can be limited.

[0052] Further, in the above technical solution, the counterforce frame body includes a counterforce frame base 31, an I-beam upper frame 6, an I-beam lower frame 17, and a middle column 8 with a slide rail 9, the number of the counterforce frame base 31 is four, and the four counterforce frame bases 31 are arranged in a rectangular array on the outer wall of the structure body 23 and are fixedly connected with the structure body 23 through expansion bolts 25, two counterforce frame bases 31 located at the top are each anchored with a ribbed upper cross beam 7, two counterforce frame bases 31 located at the bottom are each anchored with a ribbed lower cross beam 16, the two ribbed upper cross beams 7 are commonly connected with an upper rib plate at one end away from the counterforce frame base 31 through locking bolts 24 and together with the corresponding two counterforce frame bases 31 form the I-beam upper frame 6, the two ribbed lower cross beams 16 are commonly connected with a lower rib plate at one end away from the counterforce frame base 31 through locking bolts 24 and together with the corresponding two counterforce frame bases 31 form the I-beam lower frame 17, and the middle column 8 is anchored between the I-beam upper frame 6 and the I-beam lower frame 17. The counterforce frame body provides a counterforce support for sample preparation, and the end of the horizontal fixing module is in sliding fit with the slide rail 9 and can be limited through a screw.

[0053] Further, in the above technical solution, the vertical pressing module includes a lifting rod 1, a loading top beam 2, a first load sensor 3, a vertical hydraulic actuator 4, and a vertical base 5, wherein the vertical hydraulic actuator 4 is fixedly connected with the I-beam upper frame 6 through the vertical base 5 at the bottom, the first load sensor 3 and the loading top beam 2 are bolted on the output end of the vertical hydraulic actuator 4 from bottom to top, the lifting rod 1 is connected on the loading top beam 2, and the bottom end of the lifting rod 1 is anchored with the upper top beam 26 of the sample box.

[0054] Further, in the above technical solution, the horizontal fixing module includes a transverse base 10, a transverse hydraulic actuator 11, a second load sensor 12, and a loading plate 14, the transverse hydraulic actuator 11 is in sliding fit on the slide rail 9 through the transverse base 10, the loading plate 14 and the second load sensor 12 are bolted on the output end of the hydraulic actuator 11 from left to right, and the loading plate 14 is movable at the front end of the L-shaped frame 33.

[0055] Further, in the above technical solution, the L-shaped frame 33 is rotatably provided with a plurality of evenly distributed rollers 22 at one end close to the structure body 23, and the rollers 22 are detachably connected with the L-shaped frame 33. In the sample preparation process, the position of the rollers 22 controls the distance of the rigid sample box 15 to the structure body 23. In this embodiment, the number of the rollers 22 is 11, of which 3 rollers 22 are arranged on one side of the top plate of the L-shaped frame 33, and 4 rollers 22 are symmetrically arranged on both sides of the L-shaped frame 33.

[0056] Further, in the above technical solution, the vertical side plates on both sides of the L-shaped frame 33 are arranged in parallel, and the length of the convex bottom plate 27 is equal to the distance between the two vertical side plates of the L-shaped frame 33.

[0057] The lower pin 28 is composed of an L-shaped angle steel and a cutter plate, wherein the L-shaped angle steel is attached to the outside of the bottom end of the vertical side plate, and the cutter plate is integrally welded to the bottom of one end of the L-shaped angle steel. The cutter plate is made of a thin steel plate, and the opposite sides of the two cutter plates are flush with the opposite side walls of the two vertical side plates, respectively. Through the two cutter plates, the L-shaped frame 33 can be easily inserted into the soil, and the lower pin 28 is advanced into the geological body 13 during sample preparation, which stabilizes the soil sample entering the L-shaped frame 33.

[0058] Further, in the above technical solution, the convex bottom plate 27 is integrally provided with a plug-in plate on both sides, a gap is reserved between the L-shaped angle steel and the bottom end of the vertical side plate of the L-shaped frame 33, forming a lower foot groove matching the thickness of the plug-in plate, the convex bottom plate 27 and the L-shaped frame 33 are in sliding fit through the plug-in plate and the lower foot groove, and the end of the convex bottom plate 27 is designed as a wedge shape; when the soil sample is completely inserted into the L-shaped frame 33, the transverse hydraulic actuator 11 is inserted into the lower foot groove of the L-shaped frame 33 from the outside, thereby sealing the rigid sample box 15, and the wedge-shaped structure at the end of the convex bottom plate 27 is designed as a bevel, which can effectively remove the soil and reduce the insertion resistance; after the convex bottom plate 27 is installed in place, it is fixed by using the pin shaft 29 and the first fixing screw 32.

[0059] The L-shaped angle steel is attached to the outside of the bottom end of the L-shaped frame 33 and is fixedly connected with the side wall of the vertical side plate of the L-shaped frame 33 through the second fixing screw 34. The L-shaped angle steel and the side wall of the vertical side plate of the L-shaped frame 33 are both provided with through holes, the convex bottom plate 27 is provided with pin holes matching the through holes on both sides, and the through holes and the pin holes are jointly inserted with the pin shaft 29 after corresponding. The bottom of the L-shaped angle steel is connected with the bottom end of the L-shaped frame 33 through the first fixing screw 32, and the first fixing screw 32 penetrates the plug-in plate.

[0060] Further, in the above technical solution, the connecting end of the first load sensor 3 and the second load sensor 12 is electrically connected with the control host 18 through the data line 20, and the connecting end of the control host 18 is electrically connected with the operation terminal 19 through the data line 20, the control host 18 is built-in with a servo controller and a data acquisition system, the data acquisition system acquires feedback data of the first load sensor 3 and the second load sensor 12 and transmits to the servo controller for analysis and processing, the vertical hydraulic actuator 4 and the horizontal hydraulic actuator 11 are connected with a hydraulic power unit through an independently arranged oil pipe 21, and an electro-hydraulic servo valve is arranged on each of the two oil pipes 21, and the electro-hydraulic servo valve is electrically connected with the control host 18 through the data line 20. Specifically, the first load sensor 3 and the second load sensor 12 are used in subsequent vertical shear operation, sense the force borne by the sample during shearing, and feed back the sensing value to the control host 18, and remote control is realized through the operation terminal 19. In the embodiment, the first load sensor 3 and the second load sensor 12 both adopt a type of CSF-3 type spoke type tension and compression force sensor. The sensing value is transmitted to the control host 18 and the operation terminal 19 for feedback, and the operation terminal 19 controls the hydraulic power unit and the corresponding electro-hydraulic servo valve through the control host 18 according to the feedback result, so that the vertical hydraulic actuator 4 and the horizontal hydraulic actuator 11 are accurately adjusted. The operation terminal 19 observes, controls and records the displacement of the rigid sample box 15 and the pressure data of each hydraulic actuator in real time through software.

[0061] The circuit and the control involved in the present application are prior art, and will not be described in detail here.

[0062] The present application also provides a vertical shear sample preparation method, which uses the above-mentioned vertical contact surface assembly type sample box in-situ sample preparation device, and comprises the following steps:

[0063] S1, counterforce frame body positioning and installation fixing: mark four groups of installation points on the structure body 23 on one side of the geological body 13, and the structure body 23 is usually provided as a diaphragm wall structure; expand the bolt 25 at each installation point position to fix the counterforce frame base 31 at the end of the ribbed upper cross beam 7 and the ribbed lower cross beam 16 on the geological body 13, and fix the counterforce frame base 31 at the end of the ribbed upper cross beam and the ribbed lower cross beam on the counterforce frame base 31, and anchor the middle column 8 with the slide rail 9 between the ribbed upper cross beam 7 and the ribbed lower cross beam 16 to provide a counterforce support for sample preparation;

[0064] S2, install vertical pressure module: on the top of the I-beam frame 6 using screws; connecting vertical base 5, and the vertical hydraulic actuator 4 vertical upward layout and its cylinder end fixed with vertical base 5, on the output shaft of the vertical hydraulic actuator 4, using bolts from bottom to top in turn connected to the first load sensor 3 and loading top beam 2, and then connect the extension to the I-beam frame 6 bottom of the lifting rod 1, consisting of vertical (shear) servo hydraulic loading device;

[0065] S3, install horizontal fixed module: in the slide rail 9 set transverse base 10, and use screws for limiting, the cylinder end of the transverse hydraulic actuator 11 is fixed on one side of the transverse base 10, the loading plate 14 is connected to the output end of the transverse hydraulic actuator 11, and the second load sensor 12 is installed outside the output shaft of the transverse hydraulic actuator 11 and between the loading plate 14 and the cylinder end, forming a horizontal (normal) servo hydraulic loading device;

[0066] S4, layout rigid sample box 15: the open side of the I-shaped frame 33 is attached to the structure 23, and the I-shaped frame 33 is flexible and sliding, and the distance between the rigid sample box 15 and the structure 23 is controlled by selecting the size of the roller 22, the output end of the vertical hydraulic actuator 4 is adjusted to extend the length, the bottom end of the lifting rod 1 contacts the sample box top beam 26 and is fixed, and the I-shaped frame 33 is in transmission relationship; at the same time, the position of the horizontal fixing device is adjusted, so that the loading plate 14 corresponds to the lateral opening of the I-shaped frame 33 and contacts the plugging, forming a frame-shaped sample box;

[0067] S5, assembly type sample preparation method cutting sample preparation: after the frame-shaped sample box is in place, the cutter plate is suspended directly above the geological body 13, and the convex bottom plate 27 is in the pulled-out state, the position of the horizontal (normal) servo hydraulic loading device is adjusted, the loading plate 14 corresponds to the lateral opening of the I-shaped frame 33 and contacts the plugging, the output end of the vertical hydraulic actuator 4 is controlled to extend and retract, driving the lifting rod 1 to press down the I-shaped frame 33, under the action of the cutter plate and pressure, the I-shaped frame 33 cuts into the inside of the geological body 13, after the frame-shaped sample box is completely filled with soil, the convex bottom plate 27 is inserted into the corresponding lower groove position on both sides, the movement of the convex bottom plate 27 can be realized by the electric push rod 30, the end of the electric push rod 30 is installed on the slide rail 9, the output end of the electric push rod 30 is controlled to extend and retract and drive the convex bottom plate 27 to move horizontally, realizing the cutting of the soil sample, and the purpose of closing or opening the bottom end of the I-shaped frame 33; the geological body 13 is cut from the inside bottom end of the I-shaped frame 33, the excess geological body 13 is cut along the side edge of the I-shaped frame 33, and the edge is processed, forming a closed frame-shaped sample box, and the soil on both sides of the I-shaped frame 33 is excavated, and the soil sample completely enters the sample box; the sample is left in the closed frame-shaped sample box.

[0068] As Figure 9As shown, the control function of the vertical hydraulic actuator 4 servo loading during sample preparation is ensured, the net height H of the lower edge of the I-beam upper frame 6 and the top surface of the geological body 13 and the downward movement amount s of the rigid sample box satisfy the following formula:

[0069] H0+H1+H2+ΔH≤H

[0070] s=H-H1-d+Δd

[0071] Wherein, H0 is the height of the frame 33, H1 is the height of the sample box upper top beam 26, H2 is the length of the cutter plate extending out of the frame 33, ΔH is the surplus value of the net height H during installation, d is the thickness of the top plate of the frame 33, and Δd is the sample top sample preparation compression deformation amount.

[0072] In the embodiment, the geological body 13 is a soil pile with a size of length x width x height not less than 350mm x 200mm x 350mm. When setting the assembled sample box in-situ sample preparation device, H0 is 360mm, H1 is 30mm, H2 is 30mm, and ΔH is 30mm, that is, the net height H of the lower edge of the I-beam upper frame 6 and the top surface of the geological body 13 (sample raw material) is at least 360+30+30+30=450mm during installation of the equipment.

[0073] During the sample preparation construction phase, the servo actuator and the lifting rod 1 of the vertical pressure module load the rigid sample box 15, so that it vertically cuts into the soil sample, and at the same time, the soil on both sides of the sample box is removed, so that the rigid sample box 15 only bears the side friction in the box, and the stable downward movement of the rigid sample box 15 is maintained. Specifically, d is 30mm; Δd is 2mm, then the downward movement amount s of the rigid sample box 15 is 450-30-30+2=392mm, so as to prevent the top of the soil sample from being empty.

[0074] The above only describes certain exemplary embodiments of the present application by way of illustration, and it is needless to say that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present application. Therefore, the above figures and description are illustrative in nature and should not be understood as limiting the scope of protection of the claims of the present application.

Claims

1. An in-situ sample preparation device for a prefabricated sample box with a vertical contact surface, characterized in that, The system includes a reaction frame body, a rigid sample box (15), a horizontal fixing module, and a vertical pressurizing module. The rigid sample box (15) is movably disposed inside the reaction frame body. The rigid sample box (15) includes a U-shaped frame (33), lower inserts (28), and a convex base plate (27). The two lower inserts (28) are axially symmetrically distributed at the bottom of the two vertical side plates of the U-shaped frame (33). The top of the U-shaped frame (33) is detachably connected to the top beam (26) of the sample box by bolts (24). The convex base plate (27) is detachably installed between the bottom of the two vertical side plates of the U-shaped frame (33). The rear end of the U-shaped frame (33) is attached to the structure (23). The reaction frame body is installed on one side of the structure (23) and is erected on the outside of the geological body (13); The horizontal fixing module is horizontally arranged inside the reaction frame body and slides on the vertical surface of the reaction frame body. The horizontal fixing module is used to drive the loading plate (14) that is attached to the inner wall of the U-shaped frame (33). The vertical pressurization module is vertically installed on the top of the reaction frame body. The output end of the vertical pressurization module is anchored to the top beam (26) of the sample box, so that the U-shaped frame (33) cuts into the geological body (13) and prepares soil samples.

2. The in-situ sample preparation device for a assembled sample box with a vertical contact surface according to claim 1, characterized in that, The reaction frame body includes a reaction frame base (31), an upper I-beam frame (6), a lower I-beam frame (17), and a central column (8) with a slide rail (9). The number of reaction frame bases (31) is set to four, and the four reaction frame bases (31) are distributed in a rectangular array on the outer wall of the structure (23) and are fixedly connected to the structure (23) by expansion bolts (25). The two upper reaction frame bases (31) are each anchored with a ribbed upper crossbeam (7), and the two lower reaction frame bases (31) are each anchored with a ribbed lower crossbeam (16). The two ribbed upper crossbeams (7) are connected to the upper rib plate at the ends away from the reaction frame base (31) by locking bolts (24), and together with the corresponding two reaction frame bases (31), they form the upper frame (6) of the I-beam; the two ribbed lower crossbeams (16) are connected to the lower rib plate at the ends away from the reaction frame base (31) by locking bolts (24), and together with the corresponding two reaction frame bases (31), they form the lower frame (17) of the I-beam; the central column (8) is anchored between the upper frame (6) of the I-beam and the lower frame (17) of the I-beam.

3. The in-situ sample preparation device for a assembled sample box with a vertical contact surface according to claim 2, characterized in that, The vertical pressurization module includes a lifting rod (1), a loading top beam (2), a first load sensor (3), a vertical hydraulic actuator (4), and a vertical base (5). The vertical hydraulic actuator (4) is fixedly connected to the upper frame (6) of the I-beam through the bottom vertical base (5). The first load sensor (3) and the loading top beam (2) are bolted from bottom to top to the output end of the vertical hydraulic actuator (4). The lifting rod (1) is connected to the loading top beam (2), and the bottom end of the lifting rod (1) is anchored to the top beam (26) of the sample box.

4. The in-situ sample preparation device for a assembled sample box with a vertical contact surface according to claim 3, characterized in that, The horizontal fixing module includes a horizontal base (10), a horizontal hydraulic actuator (11), a second load sensor (12), and a loading plate (14). The horizontal hydraulic actuator (11) is slidably fitted onto the slide rail (9) through the horizontal base (10). The loading plate (14) and the second load sensor (12) are bolted to the output end of the hydraulic actuator (11) from left to right, and the loading plate (14) moves at the front end of the U-shaped frame (33).

5. The in-situ sample preparation device for a assembled sample box with a vertical contact surface according to claim 1, characterized in that, The slanted frame (33) has a plurality of evenly distributed rollers (22) rotatably arranged at one end near the structure (23), and the rollers (22) are detachably connected to the slanted frame (33).

6. The in-situ sample preparation device for a assembled sample box with a vertical contact surface according to claim 1, characterized in that, The vertical side plates on both sides of the U-shaped frame (33) are distributed in parallel, and the length of the convex bottom plate (27) is equal to the distance between the two vertical side plates of the U-shaped frame (33). The lower insert (28) is composed of an L-shaped angle steel and a cutting plate. The L-shaped angle steel is attached to the outer side of the bottom end of the vertical side plate, and the cutting plate is integrally welded to the bottom of one end of the L-shaped angle steel. The cutting plate is made of thin steel plate, and the opposite sides of the two cutting plates are flush with the opposite side walls of the two vertical side plates.

7. The in-situ sample preparation device for a assembled sample box with a vertical contact surface according to claim 6, characterized in that, Both sides of the convex base plate (27) are integrally provided with plug-in plates. A gap is reserved between the L-shaped angle steel and the bottom of the vertical side plate of the U-shaped frame (33) to form a bottom groove that matches the thickness of the plug-in plate. The convex base plate (27) and the U-shaped frame (33) slide in cooperation with the bottom groove through the plug-in plate, and the end of the convex base plate (27) is set as a wedge. The L-shaped angle steel is attached to the outer side of the bottom end of the U-shaped frame (33) and is fixedly connected to the side wall of the vertical side plate of the U-shaped frame (33) by the second fixing screw (34). The L-shaped angle steel and the side wall of the vertical side plate of the U-shaped frame (33) are both provided with through holes. The convex bottom plate (27) is provided with pin holes on both sides that match the through holes. After the through holes and pin holes correspond, a pin shaft (29) is inserted together. The bottom of the L-shaped angle steel is connected to the bottom end of the U-shaped frame (33) by a first fixing screw (32), and the first fixing screw (32) passes through the plug-in plate.

8. The in-situ sample preparation device for a assembled sample box with a vertical contact surface according to claim 4, characterized in that, The connection ends of the first load sensor (3) and the second load sensor (12) are electrically connected to the control host (18) via data line (20), and the connection ends of the control host (18) are electrically connected to the operation terminal (19) via data line (20). The control host (18) has a built-in servo controller and a data acquisition system. The data acquisition system acquires the feedback data of the first load sensor (3) and the second load sensor (12) and transmits it to the servo controller for analysis and processing. The vertical hydraulic actuator (4) and the horizontal hydraulic actuator (11) are connected to the hydraulic power unit via independently set oil pipes (21), and electro-hydraulic servo valves are set on both oil pipes (21). The electro-hydraulic servo valves are electrically connected to the control host (18) via data line (20).

9. A method for preparing a vertical shear specimen, employing an in-situ specimen preparation device with a prefabricated specimen box featuring a vertical contact surface as described in any one of claims 1-8, characterized in that... Includes the following steps: S1. Positioning and installation of the reaction frame body: Mark four sets of installation points on the structure (23) on one side of the geological body (13). At each installation point, use expansion bolts (25) to fix the reaction frame base (31) at the end of the upper frame (6) and lower frame (17) of the I-beam to the geological body (13). Anchor the middle column (8) with slide rail (9) between the upper crossbeam (7) and the lower crossbeam (16) of the ribbed frame to provide a reaction support for sample preparation. S2. Install vertical pressure module: Fix the top of the upper frame (6) of the I-beam with screws; connect the vertical base (5), and fix the cylinder end of the vertical hydraulic actuator (4) to the vertical base (5) after the vertical hydraulic actuator (4) is vertically arranged upward. On the output shaft of the vertical hydraulic actuator (4), the first load sensor (3) and the loading top beam (2) are connected sequentially from bottom to top with bolts. Then, the lifting rod (1) extending to the bottom of the upper frame (6) of the I-beam is connected on the loading top beam (2) to form a vertical servo hydraulic loading device. S3. Install a horizontal fixing module: Set a horizontal base (10) inside the slide rail (9) and use screws to limit it. Fix the cylinder end of the horizontal hydraulic actuator (11) to one side of the horizontal base (10), connect the loading plate (14) to the output end of the horizontal hydraulic actuator (11), and install a second load sensor (12) outside the output shaft of the horizontal hydraulic actuator (11) and between the loading plate (14) and the cylinder end to form a horizontal fixing device. S4. Setting up the rigid sample box (15): Attach one open end of the U-shaped frame (33) to the structure (23) and allow it to slide flexibly. Control the distance between the rigid sample box (15) and the structure (23) by selecting the size of the roller (22). Adjust the extension length of the output end of the vertical hydraulic actuator (4) so ​​that the bottom end of the lifting rod (1) contacts the top beam (26) of the sample box and is fixed, thus forming a transmission relationship with the U-shaped frame (33). At the same time, adjust the position of the horizontal fixing device so that the loading plate (14) corresponds to the side opening of the U-shaped frame (33) and contacts and seals it, forming a frame-shaped sample box. S5. Prefabricated sample preparation method: After the frame sample box is in place, the cutting blade is suspended above the geological body (13) and the convex bottom plate (27) is pulled out. Control the extension and retraction of the output end of the vertical hydraulic actuator (4) to drive the lifting rod (1) to press down the U-shaped frame (33). Under the action of the cutting blade and pressure, the U-shaped frame (33) cuts into the geological body (13). After the frame sample box is completely filled with soil, insert the convex bottom plate (27) into the corresponding lower groove position on both sides, cut off the geological body (13) from the bottom of the inner side of the U-shaped frame (33), cut off the excess geological body (13) along the side of the U-shaped frame (33), and trim the edges. At the same time, the soil on both sides of the U-shaped frame (33) is excavated, and the sample is formed inside the closed frame sample box.

10. A method for preparing a vertical shear specimen according to claim 9, characterized in that, During the sample preparation process, the control function of the servo loading of the vertical hydraulic actuator (4) is ensured. The net height H between the lower edge of the upper frame (6) of the I-beam and the top surface of the geological body (13) and the downward displacement s of the rigid sample box (15) satisfy the following formula: H0 + H1 + H2 + ΔH ≤ H s=H-H1-d+Δd Wherein, H0 is the height of the U-shaped frame (33), H1 is the height of the top beam (26) on the sample box, H2 is the length of the cutting plate extending out of the U-shaped frame (33), ΔH is the margin of the net height H during installation, d is the thickness of the top plate of the U-shaped frame (33), and Δd is the amount of compression deformation of the top of the soil sample.

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