Pile foundation visual observation system based on transparent granular medium and particle image velocimetry

Abstract

This invention discloses a pile foundation visualization observation system based on transparent particulate media and particle image velocimetry, relating to the field of pile foundation model testing technology. It includes a base on which test components for pile foundation testing are assembled, including a feeding component installed on the upper side of the base and an adjusting component installed on the base. This pile foundation visualization observation system based on transparent particulate media and particle image velocimetry allows a first electric push rod to cooperate with a gravity sensor, a screw and a lever, a guide rod, and a limiting strip to horizontally limit the transparent cylinder of a corresponding size while simultaneously detecting the weight of the transparent cylinder and the transparent particulate media inside. Furthermore, by adjusting the height of the gravity sensor, damage to the gravity sensor due to impact is avoided during subsequent compaction operations. A guide rail and pulley assembly, a second motor, and two sets of lead screws cooperate to adjust the horizontal position of the movable seat, the positioning component, the positioned transparent cylinder, and the transparent particulate media inside.

Description

Technical Field

[0001] This invention relates to the field of pile foundation model testing technology, specifically to a pile foundation visualization observation system based on transparent particulate media and particle image velocimetry. Background Technology

[0002] Traditional pile foundation model tests cannot directly observe pile-soil interaction, internal deformation is invisible, and bearing mechanism is difficult to quantify. Therefore, a corresponding visualization observation system is needed to optimize the test. Referring to the device and method for simultaneous observation of pile foundation model settlement in publication number CN108225261B, it includes a base, a simulated pile, a connecting rod, and two displacement sensors. The bottom of the simulated pile is rigidly connected to a base, and a hollow loading plate is fitted on the top of the simulated pile. As described in the above patent, when using existing pile foundation visualization observation systems based on transparent granular media and particle image velocimetry, most of them require filling, compacting, and pile settlement observation of different transparent cylinders in sequence. This method is cumbersome and requires frequent movement of transparent cylinders and piles, resulting in high labor intensity. It is difficult to achieve continuous and accurate feeding and standardized compaction of transparent granular media according to the corresponding size of transparent cylinders and piles. It is also difficult to accurately position, measure weight, and buffer compaction of transparent cylinders, which can easily lead to insufficient sample preparation accuracy. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a pile foundation visualization observation system based on transparent granular media and particle image velocimetry, which solves problems such as cumbersome system operation and poor adaptability to transparent cylinders and pile foundations of different sizes.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a pile foundation visualization observation system based on transparent particulate media and particle image velocimetry, comprising a base on which test components for pile foundation testing are mounted. These test components work together to achieve transparent particulate media sample preparation, pile foundation loading, and visualization observation, including:

[0005] The feeding component is installed on the upper side of the base for feeding transparent granular media;

[0006] An adjusting component, mounted on a base, is used to adjust the horizontal position of a transparent cylinder for filling transparent granular media. The adjusting component includes a guide rail fixedly connected to the base. A set of lead screws is rotatably connected to the front and rear sides of the guide rail. A pulley assembly is connected to the left side of both sets of lead screws. A second motor for driving the pulley assembly is fixedly connected to the left side of the guide rail. A movable seat is threadedly connected to both sets of lead screws. A positioning component for positioning the transparent cylinder is installed in the middle of the movable seat.

[0007] A compaction component, installed on the upper side of the base, is used to flatten transparent granular media inside a transparent cylinder. The compaction component includes a support frame fixedly connected to the base, a slide rail fixedly connected to the upper side of the support frame, a flattening component for flattening transparent granular media connected inside the slide rail, a second electric push rod fixedly connected to the rear side of the slide rail, a first camera for detecting the flattening of transparent granular media installed on the front side of the support frame, a mounting frame fixedly connected to the outer side of the middle part of the slide rail, a hydraulic cylinder fixedly connected to the middle of the mounting frame, and a pressure block fixedly connected to the extended end of the bottom of the hydraulic cylinder.

[0008] The testing component, installed on the right side of the base, is used for pile foundation settlement testing.

[0009] Several sets of second cameras are installed on the right side of the base to observe the images of the pile foundation and transparent granular medium at the lower end of the test piece. Combined with the particle image velocimetry algorithm, the displacement and velocity of the pile foundation and transparent granular medium are detected synchronously.

[0010] Preferably, the feeding component includes a storage shell fixedly connected to the upper side of the base and located at the upper end of the adjusting component. A feeding pipe is fixedly connected to the upper left side of the storage shell. A first motor is fixedly connected to the top of the storage shell. An auger driven by the first motor is rotatably connected to the middle of the inside of the storage shell. A rotary cylinder is fixedly connected to the right side of the bottom of the storage shell. A baffle that is rotatably connected to the base is fixedly connected to the bottom output end of the rotary cylinder.

[0011] Preferably, the output end of the first motor is coaxially and fixedly connected to the auger, the bottom of the storage shell is provided with a discharge port near the outer end of the auger, and the baffle is located below the discharge port and fits against the bottom of the storage shell.

[0012] Preferably, the guide rail is arranged on the base along the X-axis direction, the driving pulley and the driven pulley in the pulley assembly are respectively coaxially fixedly connected to a set of lead screws, the second motor is coaxially fixedly connected to the driving pulley, the movable seat is slidably connected in the guide rail, and the compaction component is located between the feeding component and the detection component.

[0013] Preferably, the positioning component includes several sets of first electric push rods fixedly connected to the bottom of the movable seat. A gravity sensor is fixedly connected to the extended side of the top of the first electric push rod near the upper end of the movable seat. Three sets of screws are evenly distributed axially around the outside of the gravity sensor on the movable seat. The screws are threadedly connected to the movable seat and are rotatably connected to a limit strip via a bearing near the end of the gravity sensor. A set of guide rods that are slidably connected to the movable seat are fixedly connected to the upper and lower sides of the limit strip near the screws. A lever is coaxially fixedly connected to the side of the screw away from the limit strip. The surface of the guide rod is provided with a scale groove with a built-in scale strip. The upper side of the movable seat near the first electric push rod is provided with a storage groove for storing the gravity sensor.

[0014] Preferably, the flattening component includes a slide block slidably connected within the slide rail and fixedly connected to the extended side of the second electric push rod. Three sets of transmission rods are vertically slidably connected to the middle of the slide block. A support block is fixedly connected to the top of the transmission rod corresponding to the lower side of the pressure block. A spring fixedly connected to the upper side of the slide block is fixedly connected to the bottom of the support block near the outer side of the transmission rod. A bellows fixedly connected to the upper side of the slide block near the outer end of the spring is fixedly connected to the other side of the slide block and fixedly connected to the support block. A pressure plate matching the inner diameter of the transparent cylinder is fixedly connected to the bottom of the transmission rod near the lower end of the slide block. The slide rail is arranged on the support frame along the Y-axis direction.

[0015] Preferably, the detection component includes three sets of limiting frames fixedly connected to the upper right side of the base. A support frame is slidably connected to the inner side of the limiting frame along the X-axis. A storage shell is vertically slidably connected to the top of the support frame. An infrared sensor for detecting the vertical displacement of the storage shell is fixedly connected to the top right side of the support frame. A detection block for assisting in detecting the displacement of the pile foundation is fixedly connected to the lower right side of the storage shell. Several sets of counterweights are slidably connected inside the storage shell. An extraction component for removing the counterweights is also connected inside the storage shell. A guide block for guiding the pile foundation is threadedly connected to the base near the lower side of the storage shell.

[0016] Preferably, the guide block is vertically provided with a guide groove that matches the size of the pile foundation, the detection block is located directly below the detection end of the infrared sensor, the extraction component includes a support plate that is slidably connected to the inside of the storage shell and whose upper side is attached to a set of counterweights, a tie rod is vertically fixedly connected to the middle of the support plate, the middle of the counterweight is provided with a slot vertically through the tie rod, and the bottom of the support plate is attached to the bottom of the inside of the storage shell.

[0017] Beneficial effects

[0018] This invention provides a pile foundation visualization observation system based on transparent granular media and particle image velocimetry. Compared with existing technologies, it has the following advantages:

[0019] (1) The pile foundation visualization observation system based on transparent granular medium and particle image velocity measurement, by setting adjustment and compaction components in the system, allows the first electric push rod to cooperate with the gravity sensor, screw and lever, guide rod and limit bar to horizontally limit the transparent cylinder of the corresponding size, while having the function of detecting the weight of the transparent cylinder and the transparent granular medium inside it. In addition, by adjusting the height of the gravity sensor, the gravity sensor is prevented from being damaged by impact during the subsequent compaction operation. The guide rail and pulley assembly, the second motor and two sets of screws cooperate to adjust the horizontal position of the movable seat, positioning component, the positioned transparent cylinder and the transparent granular medium inside it, which helps to feed and compact the transparent cylinder. The support frame, slide rail, second electric push rod, slide seat, transmission rod, support block and spring cooperate to switch the position of the pressure plate of the corresponding size as needed and to flatten the transparent granular medium inside the transparent cylinder by adjusting the vertical height of the pressure plate, thus quickly realizing the prerequisite for the corresponding pile foundation visualization observation.

[0020] (2) The pile foundation visualization observation system based on transparent granular medium and particle image velocity measurement, by setting a feeding component in the system, when the adjusting component moves the corresponding transparent cylinder to the bottom of the storage shell in the horizontal direction, the rotating cylinder and the baffle move together to control the opening of the discharge end at the bottom of the storage shell, so that the first motor and the auger work together to introduce the transparent granular medium in the storage shell into the transparent cylinder, thereby realizing continuous and rapid feeding of multiple sets of transparent cylinders, without the need for the user to manually store and retrieve the transparent cylinders, thus improving the efficiency of transparent medium feeding.

[0021] (3) The pile foundation visualization observation system based on transparent granular medium and particle image velocimetry, by setting a detection component in the system, after the axial end of the transparent cylinder is aligned with the guide groove on the guide block, the model pile foundation of the corresponding size is inserted into the transparent granular medium inside the transparent cylinder through the guide groove on the guide block. The position of the storage shell is adjusted to the top of the model pile foundation and in contact with it in conjunction with the limiting frame. The counterweight block of the corresponding weight is introduced into the storage shell. The storage shell transmits the increased weight to the model pile foundation through force transmission, realizing the movement of the pile foundation. In conjunction with the gravity sensor and infrared sensor, the vertical displacement and load change of the model pile foundation are detected. This setting is convenient for vertically limiting the corresponding pile foundation, and applying the corresponding gravity to the pile foundation and detecting the pile foundation displacement as needed. In conjunction with the second camera, the particle image velocimetry algorithm is combined to realize the synchronous detection of displacement and velocity of the pile foundation and transparent granular medium. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0023] Figure 2 This is an enlarged cross-sectional view of the present invention;

[0024] Figure 3 This is an enlarged cross-sectional view of the feeding component of this invention;

[0025] Figure 4 This is a partial enlarged cross-sectional view of the positioning component of the present invention;

[0026] Figure 5 This is a partial enlarged cross-sectional view of the compaction component of the present invention;

[0027] Figure 6 This is a partial enlarged cross-sectional view of the testing component of the present invention;

[0028] Figure 7 This is a partial enlarged cross-sectional view of the extractor of the present invention.

[0029] In the diagram: 1. Base; 2. Feeding component; 21. Storage shell; 22. Feeding pipe; 23. First motor; 24. Screw; 25. Rotary cylinder; 26. Baffle; 3. Adjusting component; 31. Guide rail; 32. Lead screw; 33. Pulley assembly; 34. Second motor; 35. Movable seat; 36. Positioning component; 361. First electric push rod; 362. Gravity sensor; 363. Screw; 364. Pulley block; 365. Guide rod; 366. Limiting strip; 4. Compacting component; 41. Support frame; 42. Slide rail; 4 3. Mounting bracket; 44. Hydraulic cylinder; 45. Pressure block; 46. Second electric push rod; 47. Flattening component; 471. Slide seat; 472. Transmission rod; 473. Support block; 474. Spring; 475. Pressure plate; 476. Corrugated pipe; 48. First camera; 5. Detection component; 51. Limiting frame; 52. Support frame; 53. Storage shell; 54. Infrared sensor; 55. Detection block; 56. Guide block; 57. Counterweight block; 58. Extraction component; 581. Support plate; 582. Pull rod; 6. Second camera. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Please see Figures 1-7 The present invention provides the following three technical solutions:

[0032] The first implementation method is a pile foundation visualization observation system based on transparent particulate medium and particle image velocimetry, including a base 1, with the long side of the base 1 as the X-axis direction and the short side of the base 1 as the Y-axis direction. The base 1 is equipped with a test component for pile foundation testing. The test component works together to realize transparent particulate medium sample preparation, pile foundation loading and visualization observation, including: a feeding component 2, which is installed on the upper side of the base 1 for feeding transparent particulate medium.

[0033] Adjusting component 3, installed on base 1, is used to adjust the horizontal position of the transparent cylinder for filling transparent granular media. Adjusting component 3 includes a guide rail 31 fixedly connected to base 1. A set of lead screws 32 are rotatably connected to the front and rear sides of the guide rail 31. A pulley assembly 33 is connected to the left side of the two sets of lead screws 32. A second motor 34 for driving the pulley assembly 33 is fixedly connected to the left side of the guide rail 31. The second motor 34 is a servo motor. A movable seat 35 is threadedly connected to the two sets of lead screws 32. A positioning component 36 for positioning the transparent cylinder is installed in the middle of the movable seat 35. The guide rail 31 is set on base 1 along the X-axis. The driving pulley and driven pulley in the pulley assembly 33 are coaxially fixedly connected to a set of lead screws 32. The second motor 34 is coaxially fixedly connected to the driving pulley. The movable seat 35 is slidably connected in the guide rail 31. The compaction component 4 is located between the feeding component 2 and the detection component 5.

[0034] The positioning component 36 includes several sets of first electric push rods 361 fixedly connected to the bottom of the movable seat 35. A gravity sensor 362 is fixedly connected to the top extension side of the first electric push rod 361 near the upper end of the movable seat 35. Three sets of screws 363 are evenly distributed axially around the outside of the gravity sensor 362 on the movable seat 35. The screws 363 are threaded to the movable seat 35 and are rotatably connected to a limit strip 366 via a bearing at the end near the gravity sensor 362. A set of guide rods 365 that are slidably connected to the movable seat 35 are fixedly connected to the upper and lower sides of the limit strip 366 near the screws 363. A lever 364 is coaxially fixedly connected to the side of the screws 363 away from the limit strip 366. The surface of the guide rod 365 is provided with a scale groove with a built-in scale strip. The upper side of the movable seat 35 near the first electric push rod 361 is provided with a storage groove for storing the gravity sensor 362.

[0035] Compactor 4, installed on the upper side of base 1, is used to flatten the transparent granular medium inside the transparent cylinder. Compactor 4 includes a support frame 41 fixedly connected to base 1, a slide rail 42 fixedly connected to the upper side of support frame 41, a flattening component 47 for flattening the transparent granular medium connected inside slide rail 42, a second electric push rod 46 fixedly connected to the rear side of slide rail 42, a first camera 48 for detecting the flattening of the transparent granular medium installed on the front side of support frame 41, a mounting frame 43 fixedly connected to the outer side of the middle part of slide rail 42, a hydraulic cylinder 44 fixedly connected to the middle of mounting frame 43, and a pressure block 45 fixedly connected to the bottom extension end of hydraulic cylinder 44; Detector 5, installed on the right side of base 1, is used for pile foundation settlement testing; Several sets of second cameras 6 are respectively installed on the right side of base 1 to observe the pile foundation and transparent granular medium images at the lower end of detector 5, and combined with particle image velocity measurement algorithm to realize synchronous detection of displacement and velocity of pile foundation and transparent granular medium;

[0036] The leveling component 47 includes a slide block 471 slidably connected within the slide rail 42 and fixedly connected to the extended side of the second electric push rod 46. Three sets of transmission rods 472 are vertically slidably connected to the middle of the slide block 471. A support block 473 is fixedly connected to the top of the transmission rod 472 corresponding to the lower side of the pressure block 45. A spring 474, which is fixedly connected to the upper side of the slide block 471, is fixedly connected to the bottom of the support block 473 near the outer side of the transmission rod 472. Another side of the slide block 471, which is fixedly connected to the support block 473, is fixedly connected to the upper side of the slide block 471 near the outer end of the spring 474. The bellows 476, the bottom of the transmission rod 472 near the lower end of the slide block 471, is fixedly connected to a pressure plate 475 that matches the inner diameter of the transparent cylinder. All three pressure plates 475 are circular plates with diameters matching the inner wall diameter of the corresponding transparent cylinder. The slide rail 42 is set on the support frame 41 along the Y-axis. The first electric push rod 361 cooperates with the gravity sensor 362 to provide support and gravity detection for the transparent cylinder. The gravity sensor 362 is surrounded by three evenly distributed screws 363, a lever 364, and a guide rod. 365 and 366 work together to limit the size of the transparent cylinder. The guide rail 31, pulley assembly 33, second motor 34, and two sets of lead screws 32 work together to adjust the horizontal position of the movable seat 35, positioning component 36, the positioned transparent cylinder, and the transparent granular medium inside, facilitating subsequent feeding of the transparent cylinder and flattening of the transparent granular medium inside. The compaction component 4 includes a support frame 41, slide rail 42, second electric push rod 46, slide block 471, transmission rod 472, and support block 473. The spring 474, in conjunction with the pressure plate 475 of the corresponding size, adjusts the horizontal position of the pressure plate 475 as required, so that the mounting bracket 43, hydraulic cylinder 44, and pressure block 45 apply downward pressure to the support block 473. Through the transmission of force, the pressure plate 475 flattens the transparent granular medium inside the transparent cylinder. After the pressure block 45 is reset, the spring 474 promotes the reset of the support block 473, transmission rod 472, and pressure plate 475. The bellows 476 expands and contracts under the traction of the support block 473, which protects the outside of the spring 474.

[0037] The main difference between the second implementation method and the first implementation method is that:

[0038] The feeding component 2 includes a storage shell 21 fixedly connected to the upper side of the base 1 and located at the upper end of the adjusting component 3. A feeding pipe 22 is fixedly connected to the upper left side of the storage shell 21. A first motor 23 is fixedly connected to the top of the storage shell 21. An auger 24 driven by the first motor 23 is rotatably connected to the middle of the inside of the storage shell 21. A rotary cylinder 25 is fixedly connected to the bottom right side of the storage shell 21. A baffle 26 rotatably connected to the base 1 is fixedly connected to the bottom output end of the rotary cylinder 25.

[0039] The output end of the first motor 23 is coaxially and fixedly connected to the auger 24. The bottom of the storage shell 21 is provided with a discharge port near the outer end of the auger 24. The baffle 26 is located below the discharge port and fits against the bottom of the storage shell 21. When the adjusting component 3 moves the corresponding transparent cylinder to the bottom of the storage shell 21 in the horizontal direction, the rotary cylinder 25 and the baffle 26 move together to control the opening of the discharge end at the bottom of the storage shell 21. The first motor 23 and the auger 24 work together to introduce the transparent granular medium in the storage shell 21 into the transparent cylinder. At the same time, the gravity sensor 362 continuously detects the total weight of the transparent cylinder and the transparent granular medium.

[0040] The main difference between the third and second implementation methods is that:

[0041] The detection component 5 includes three sets of limiting frames 51 fixedly connected to the upper right side of the base 1. A support frame 52 is slidably connected to the inner side of the limiting frame 51 along the X-axis. A storage shell 53 is vertically slidably connected to the top of the support frame 52. An infrared sensor 54 for detecting the vertical displacement of the storage shell 53 is fixedly connected to the top right side of the support frame 52. The components also include a first motor 23, a rotary cylinder 25, a second motor 34, a first electric push rod 361, a gravity sensor 362, a second electric push rod 46, a first camera 48, and an infrared sensor 54. All cameras 6 are electrically connected to an external controller. A detection block 55 for assisting in detecting pile displacement is fixedly connected to the lower right side of the storage shell 53. Several sets of counterweights 57 are slidably connected inside the storage shell 53. An extraction piece 58 for removing the counterweights 57 is also connected inside the storage shell 53. A guide block 56 for guiding the pile is threadedly connected to the lower side of the base 1 near the storage shell 53. This setting makes it easy to replace the corresponding guide block 56 according to the model pile of the corresponding size, improves the adaptability of the device and ensures that the model pile moves vertically downward.

[0042] The guide block 56 has a vertically penetrating guide groove that matches the size of the pile foundation. The detection block 55 is located directly below the detection end of the infrared sensor 54. The extraction component 58 includes a support plate 581 that is slidably connected to the inside of the housing 53 and whose upper side is attached to a set of counterweights 57. A tie rod 582 is vertically fixedly connected to the middle of the support plate 581. A slot is vertically penetrating the middle of the counterweights 57 corresponding to the tie rod 582. The bottom of the support plate 581 is attached to the bottom of the inside of the housing 53. After the axial end of the transparent cylinder is aligned with the guide groove on the guide block 56, the model pile foundation of the corresponding size is inserted into the transparent granular medium inside the transparent cylinder through the guide groove on the guide block 56 and adjusted in conjunction with the limiting frame 51. The housing 53 is positioned directly above and in contact with the model pile foundation. A counterweight 57 of corresponding weight is introduced into the housing 53. The housing 53 transmits the increased weight to the model pile foundation through force transmission, realizing the movement of the pile foundation. In conjunction with the gravity sensor 362 and the infrared sensor 54, the vertical displacement and load changes of the model pile foundation are detected. At the same time, the second camera 6 observes the failure mode of the pile surface and the surrounding soil through the transparent cylinder, which is convenient for subsequent drawing of load-settlement curves. The counterweight 57 is piled up in the support plate 581. When it is necessary to remove the counterweight 57 from the housing 53, the pull rod 582 and the support plate 581 are pulled to remove the piled counterweight 57.

[0043] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.

[0044] In use, the user places three sets of transparent cylinders of different diameters, each designed to hold transparent granular media, into the three sets of positioning members 36 on the movable base 35, ensuring the transparent cylinders are positioned above the gravity sensor 362. Based on the diameter of the transparent cylinders, the user moves the three sets of levers 364 and screws 363 respectively. The screws 363 move the limiting strips 366 and the two sets of guide rods 365 towards the edge of the transparent cylinder. The position of the limiting strips 366 is determined by the scale on the guide rods 365, ensuring that the three sets of limiting strips 366 have the same displacement, allowing them to fit against the edge of the transparent cylinder, thus limiting the horizontal position of the transparent cylinder. After positioning, the first electric push rod 361 adjusts the height of the gravity sensor 362, causing the gravity sensor 362 to lift the transparent cylinder from the vertical side, providing vertical support. The gravity sensor 362 detects... After the weight of the transparent cylinder is measured and the positioning is completed, the second motor 34, in conjunction with the pulley assembly 33, two sets of guide rails 31, and lead screw 32, adjusts the horizontal position of the movable seat 35, three sets of positioning parts 36, and the transparent cylinder along the X-axis. This moves the transparent cylinder containing the transparent granular medium to the underside of the storage shell 21. The rotary cylinder 25 drives the baffle 26 to rotate, opening the bottom discharge end of the storage shell 21. The first motor 23 drives the auger 24 to rotate, and the rotating auger 24 discharges the transparent granular medium from the storage shell 21. The discharged transparent granular medium falls into the transparent cylinder. During this process, the gravity sensor 362 continuously detects the total weight of the transparent cylinder and the transparent granular medium. Once the weight of the transparent granular medium reaches a suitable range, the first motor 23 is turned off. The above operation is repeated to feed the remaining two sets of transparent cylinders.

[0045] The bottom of the sealed storage shell 21 is closed, and the horizontal position of the transparent cylinder is adjusted further. The transparent cylinder, which is required to be compacted for the transparent granular medium, is moved to the lower side of the flattening component 47. The second electric push rod 46 adjusts the horizontal position of the flattening component 47 along the Y-axis, so that the pressure plate 475, which matches the inner diameter of the transparent cylinder, is moved to the upper side of the transparent cylinder. The height of the gravity sensor 362 is adjusted to separate it from the transparent cylinder. At this time, the upper side of the movable seat 35 contacts the transparent cylinder and provides support for it. The hydraulic cylinder 44 drives the pressure block 45 to move downward. After the downward-moving pressure block 45 contacts the support block 473, it pushes the transmission rod 472 and the pressure plate 475 to move downward. The support block 473 has a spring on the slide 471. Spring 474 is compressed, and after pressure plate 475 enters the transparent cylinder, it contacts and compacts the transparent granular medium. The compaction status of the transparent granular medium inside the transparent cylinder is detected by the first camera 48. After the operation is completed, support block 473 is reset. Under the action of spring 474, spring 474 pushes support block 473, transmission rod 472 and pressure plate 475 upward to reset. The above operation is repeated to compact the remaining transparent cylinders. Gravity sensor 362 is reset, so that gravity sensor 362 lifts the transparent cylinder containing the compacted transparent granular medium again. The horizontal position of the transparent cylinder is adjusted so that the three sets of transparent cylinders are aligned with the guide blocks 56 in the three sets of detection components 5 respectively.

[0046] Three sets of model piles of different sizes are inserted into the transparent granular medium inside the transparent cylinder via the guide groove on the guide block 56. The receiving shell 53 is pulled along the support frame 52 until it is higher than the top of the model pile. The support frame 52 and the receiving shell 53 are pulled horizontally along the limiting frame 51 so that the receiving shell 53 is moved to the top of the model pile. The receiving shell 53 is then released so that its bottom is in contact with the top of the model pile. At this time, the gravity sensor 362 detects the weight of the transparent cylinder, transparent granular medium, model pile, receiving shell 53, detection block 55, and extraction component 58 to determine the initial weight, while the infrared sensor 54 determines the initial height of the receiving shell 53 by measuring the position of the detection block 55. According to the experimental requirements, a counterweight 57 of the corresponding weight is inserted into the tie rod 582 inside the housing 53. The housing 53 transmits the increased weight to the model pile foundation through force transmission. The model pile foundation gradually inserts into the depth of the transparent granular medium. At the same time, the housing 53, the detection block 55, and the counterweight 57 move downward synchronously. Based on the detection of the height change of the detection block 55 by the infrared sensor 54, the downward distance of the model pile foundation is indirectly obtained. Meanwhile, the gravity sensor 362 detects the change of load at all times. The second camera 6 observes the failure mode of the pile surface and the surrounding soil through the transparent cylinder, organizes the recorded load and settlement data into a table, and plots the load-settlement curve.

[0047] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0048] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A pile foundation visualization observation system based on transparent particulate media and particle image velocimetry, comprising a base (1), characterized in that: The base (1) is equipped with a test assembly for pile foundation testing. The test assembly works in concert to achieve transparent particulate medium sample preparation, pile foundation loading, and visual observation, including: The feeding component (2) is installed on the upper side of the base (1) for feeding transparent granular media; Adjustment component (3), installed on base (1) for adjusting the horizontal position of transparent cylinder for filling transparent granular medium, the adjustment component (3) includes a guide rail (31) fixedly connected to base (1), a set of lead screws (32) are rotatably connected to the front and rear sides of the guide rail (31), the left side of the two sets of lead screws (32) are connected to a pulley assembly (33), the left side of the guide rail (31) is fixedly connected to a second motor (34) for driving the pulley assembly (33), the two sets of lead screws (32) are threadedly connected to a movable seat (35), and a positioning component (36) for positioning transparent cylinder is installed in the middle of the movable seat (35); A compaction component (4) is installed on the upper side of the base (1) for flattening the transparent granular medium inside the transparent cylinder. The compaction component (4) includes a support frame (41) fixedly connected to the base (1). A slide rail (42) is fixedly connected to the upper side of the support frame (41). A flattening component (47) for flattening the transparent granular medium is connected inside the slide rail (42). A second electric push rod (46) is fixedly connected to the rear side of the slide rail (42). A first camera (48) for detecting the flattening of the transparent granular medium is installed on the front side of the support frame (41). A mounting frame (43) is fixedly connected to the outer side of the middle part of the slide rail (42). A hydraulic cylinder (44) is fixedly connected to the middle part of the mounting frame (43). A pressure block (45) is fixedly connected to the bottom extension end of the hydraulic cylinder (44). Test piece (5) is installed on the right side of base (1) for pile foundation settlement testing; Several sets of second cameras (6) are installed on the right side of the base (1) to observe the images of the pile foundation and transparent granular medium at the lower end of the detection component (5). Combined with the particle image velocity measurement algorithm, the displacement and velocity of the pile foundation and transparent granular medium are detected synchronously.

2. The pile foundation visualization observation system based on transparent particulate media and particle image velocimetry according to claim 1, characterized in that: The feeding component (2) includes a storage shell (21) fixedly connected to the upper side of the base (1) and located at the upper end of the adjusting component (3). A feeding pipe (22) is fixedly connected to the upper left side of the storage shell (21). A first motor (23) is fixedly connected to the top of the storage shell (21). An auger (24) driven by the first motor (23) is rotatably connected to the middle of the inside of the storage shell (21). A rotary cylinder (25) is fixedly connected to the right side of the bottom of the storage shell (21). A baffle (26) rotatably connected to the base (1) is fixedly connected to the bottom output end of the rotary cylinder (25).

3. The pile foundation visualization observation system based on transparent particulate media and particle image velocimetry according to claim 2, characterized in that: The output end of the first motor (23) is coaxially fixedly connected to the auger (24). The bottom of the storage shell (21) is provided with a discharge port near the outer end of the auger (24). The baffle (26) is located below the discharge port and fits against the bottom of the storage shell (21).

4. The pile foundation visualization observation system based on transparent particulate media and particle image velocimetry according to claim 1, characterized in that: The guide rail (31) is set on the base (1) along the X-axis direction. The active pulley and the driven pulley in the pulley assembly (33) are coaxially fixedly connected to a set of lead screws (32). The second motor (34) is coaxially fixedly connected to the active pulley. The movable seat (35) is slidably connected in the guide rail (31). The compaction component (4) is located between the feeding component (2) and the detection component (5).

5. The pile foundation visualization observation system based on transparent particulate media and particle image velocimetry according to claim 1, characterized in that: The positioning component (36) includes several sets of first electric push rods (361) fixedly connected to the bottom of the movable seat (35). A gravity sensor (362) is fixedly connected to the extended side of the first electric push rod (361) near the upper end of the movable seat (35). Three sets of screws (363) are evenly distributed axially around the outside of the gravity sensor (362) on the movable seat (35). The screws (363) are threaded to the movable seat (35) and rotatably connected to the end near the gravity sensor (362) via a bearing. A limiting strip (366) is fixedly connected to a set of guide rods (365) that are slidably connected to the movable seat (35) on the upper and lower sides of the limiting strip (363) near the screw (363). A lever (364) is fixedly connected to the screw (363) on the side away from the limiting strip (366). The guide rod (365) has a scale groove with a built-in scale bar on its surface. The movable seat (35) has a storage slot for storing the gravity sensor (362) on the upper side near the first electric push rod (361).

6. The pile foundation visualization observation system based on transparent particulate media and particle image velocimetry according to claim 1, characterized in that: The flattening component (47) includes a slide block (471) that is slidably connected inside the slide rail (42) and fixedly connected to the extended side of the second electric push rod (46). Three sets of transmission rods (472) are vertically slidably connected in the middle of the slide block (471). A support block (473) is fixedly connected to the top of the transmission rod (472) corresponding to the lower side of the pressure block (45). A spring (474) that is fixedly connected to the upper side of the slide block (471) is fixedly connected to the bottom of the support block (473) near the outer side of the transmission rod (472). A bellows (476) that is fixedly connected to the support block (473) on the other side is fixedly connected to the upper side of the slide block (471) near the outer end of the spring (474). A pressure plate (475) that matches the inner diameter of the transparent cylinder is fixedly connected to the bottom of the transmission rod (472) near the lower end of the slide block (471). The slide rail (42) is set on the support frame (41) along the Y-axis direction.

7. The pile foundation visualization observation system based on transparent particulate media and particle image velocimetry according to claim 1, characterized in that: The detection component (5) includes three sets of limiting frames (51) fixedly connected to the upper right side of the base (1). A support frame (52) is slidably connected to the inner side of the limiting frame (51) along the X-axis direction. A storage shell (53) is vertically slidably connected to the top of the support frame (52). An infrared sensor (54) for detecting the vertical displacement of the storage shell (53) is fixedly connected to the right side of the top of the support frame (52). A detection block (55) for assisting in detecting the displacement of the pile foundation is fixedly connected to the lower right side of the storage shell (53). Several sets of counterweights (57) are slidably connected inside the storage shell (53). An extraction component (58) for removing the counterweights (57) is also connected inside the storage shell (53). A guide block (56) for guiding the pile foundation is threadedly connected to the lower side of the base (1) near the storage shell (53).

8. The pile foundation visualization observation system based on transparent particulate media and particle image velocimetry according to claim 7, characterized in that: The guide block (56) is vertically provided with a guide groove that matches the size of the pile foundation. The detection block (55) is located directly below the detection end of the infrared sensor (54). The extraction component (58) includes a support plate (581) that is slidably connected to the inside of the storage shell (53) and whose upper side is attached to a set of counterweights (57). A pull rod (582) is vertically fixedly connected to the middle of the support plate (581). A slot is vertically provided in the middle of the counterweight (57) corresponding to the pull rod (582). The bottom of the support plate (581) is attached to the bottom of the inside of the storage shell (53).

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