A static sounding autonomous penetration system based on bionics

Abstract

This invention discloses a biomimetic-based autonomous static cone penetration test system, comprising a controller, an upper expansion device, a loading device, a lower telescoping device, and a static cone penetration probe. The upper expansion device includes an elastic membrane surrounding a hollow cylindrical tube with permeable holes. The loading device includes four sets of hydraulic loading units. The lower telescoping device includes six radially expandable and retractable metal blades. Water is injected into the elastic membrane to cause it to expand and compress the surrounding soil, providing the reaction force required for the extension of the loading device. By controlling the four sets of hydraulic loading units in the loading device, the probe can penetrate the soil vertically and change its direction of travel. When the metal blades unfold, the bearing capacity of the soil above them provides the reaction force required for the retraction of the loading device. This invention eliminates the need for a reaction device on the ground surface and a probe rod between the loading device and the static cone penetration probe. This invention causes minimal disturbance to the surrounding environment and can be used in locations inaccessible to large machinery, expanding the applicability of static cone penetration test sites.

Description

Technical Field

[0001] This invention relates to the field of geotechnical in-situ testing, specifically a biomimetic-based static cone penetration test autonomous system. This system is suitable for conducting static cone penetration tests in locations where large machinery cannot reach, and is used for soil layer division and estimation of soil physical and mechanical properties. Background Technology

[0002] Before designing and constructing various engineering projects, it is necessary to measure the physical and mechanical properties of the foundation soil through in-situ testing or laboratory experiments. Compared with laboratory testing, in-situ testing has advantages such as reflecting the characteristics of the soil under natural stress, a large measurement range, and a short test cycle. Static cone penetration testing (CPPT) is an in-situ testing technique that uses quasi-static force to press a conical probe into the soil at a constant rate through a series of probes, measuring the cone tip resistance, sidewall friction, and pore water pressure experienced by the probe during penetration. The test results of static cone penetration testing can be used for soil layer division, soil classification, and estimation of the physical and mechanical properties of each soil layer, making it one of the most widely used in-situ testing techniques in the field of geotechnical engineering.

[0003] The penetration depth of a static cone penetration test (SPT) depends primarily on the capacity of the penetrator and the magnitude of the reaction force it can provide. Therefore, traditional SPT systems often include a large reaction force device. This device serves to fix the pressurization device and provide the necessary reaction force for the probe during penetration; it can be categorized as gravity-based or anchor-based. However, in some locations, such as the deep sea or deep space, where large reaction force devices are inaccessible to humans and large machinery, traditional SPT systems significantly limit the applicable site range for static cone penetration tests.

[0004] Bionics is a discipline that implements and effectively applies biological functions in engineering. Razor clams live in shallow seas; they are in the water at high tide and burrow into the sand at low tide. The razor clam first uses its hard outer shell to support the soil on both sides, then its soft inner crystalline shaft burrows downwards. Once the inner crystalline shaft has burrowed to a certain depth, the outer shell contracts and moves downwards along the inner crystalline shaft, repeating this process to continuously burrow into the sandy mudflats. Earthworms move by the alternating contraction and relaxation of longitudinal and circular muscles, along with the coordination of setae on their body surface. When an earthworm moves forward, the setae at the rear of its body embed themselves in the soil, at which point the circular muscles contract and the longitudinal muscles relax, propelling the body forward. Then, the setae at the front of the body embed themselves in the soil, at which point the longitudinal muscles contract and the circular muscles relax, shortening the body and propelling it forward.

[0005] Based on the principles of "clams burrowing in sand" and "earthworm movement," this patented invention provides a static cone penetration test system. Traditional static cone penetration tests require bulky reaction devices, a series of probes, and can only achieve vertical penetration. Summary of the Invention

[0006] To address the aforementioned existing technologies, this invention provides a biomimetic-based autonomous static penetration system. This system utilizes the reaction force provided by the surrounding soil and rock mass itself, thus eliminating the need for reaction force devices and probes. Furthermore, it can change direction during penetration. Compared to traditional penetration systems, this autonomous penetration system exhibits less disturbance to the surrounding environment, lower energy consumption, and lower cost.

[0007] To solve the above-mentioned technical problems, the present invention proposes a biomimetic-based static cone penetration autonomous penetration system, including an upper expansion device, a loading device, a lower expansion and contraction device, and a static cone probe.

[0008] The upper expansion device includes an expansion device housing, which is composed of an expansion device base, an expansion device sidewall, and an expansion device top plate. The expansion device top plate is provided with a water injection hole. The expansion device sidewall includes a hollow cylindrical tube with water permeable holes on its wall. The hollow cylindrical tube is covered with an elastic membrane. The upper and lower ends of the hollow cylindrical tube are fixedly connected to the expansion device base and the expansion device top plate, respectively. The upper and lower ends of the elastic membrane are sealed to the expansion device base and the expansion device top plate, respectively. When the upper expansion device needs to provide reaction force, pressurized water is injected into the hollow cylindrical tube through the water injection hole, and the pressurized water fills the elastic membrane through the water permeable holes.

[0009] The loading device includes a loading device housing, which is composed of a loading device base, a loading device sidewall, and a loading device top plate. The loading device sidewall is made of a circumferentially rigid and axially extensible material. Four sets of hydraulic loading units are respectively arranged between the loading device base and the loading device top plate in a front-to-back symmetrical and left-to-right symmetrical manner. Each set of hydraulic loading units includes a hydraulic cylinder, a piston, and a piston rod.

[0010] The expansion device base and the loading device top plate are fixedly connected; a steel pipe runs from the expansion device top plate through the hollow cylindrical tube and the expansion device base to the loading device top plate, and the hydraulic pipeline of the hydraulic cylinder is connected to the hydraulic pump through the steel pipe; a bearing hole is provided at the center of the bottom surface of the loading device base, and six straight grooves are arranged radially around the bearing hole.

[0011] The lower telescopic device includes six metal blades and a central rotating shaft driven by a servo motor. A rotating arm is fixed on the central rotating shaft, and the rotating arm includes six fixed rods, one end of which is fixed to the rotating shaft. A transmission and actuation mechanism is provided between each of the six fixed rods and the six metal blades, each transmission and actuation mechanism including a connecting rod. One end of the connecting rod is hinged to the other end of a fixed rod via a hinge pin, and the other end of the connecting rod is hinged to a slider via a hinge. The slider is embedded in the linear slide groove and slides within the groove. Each metal blade is hinged to both the hinge pin and the hinge in the same transmission and actuation mechanism. The servo motor is controlled and driven to rotate 60° clockwise or counterclockwise. The central rotating shaft drives all the metal blades to rotate synchronously via the transmission and actuation mechanisms, and they telescopically extend and retract along the radial direction of the central rotating shaft.

[0012] The static cone penetration probe includes a cone tip resistance sensor, a side wall friction sensor, a pore water pressure sensor, and an inclinometer, all of which are connected to the controller; the servo motor, the hydraulic pump, and the water injection pipe are all connected to the controller.

[0013] Furthermore, in the biomimetic-based static probing autonomous penetration system described in this invention, wherein:

[0014] The six fixed rods and six metal blades are arranged radially.

[0015] After the servo motor is driven, the rotating arm rotates synchronously under the drive of the central rotating shaft. The fixed rod pulls the connecting rod in the transmission and execution mechanism, so that the hinge moves closer to or away from the central rotating shaft, thereby causing the metal blade to unfold and retract in its plane.

[0016] The top plate of the static cone penetrometer is equipped with a bearing, and the two ends of the central rotating shaft are respectively supported between the loading device base and the top plate of the static cone penetrometer by the bearing.

[0017] By controlling the extension of the four piston rods in the loading device, the penetration direction of the static cone penetrometer can be changed.

[0018] The servo motor's wires are connected to the power source via the steel pipe.

[0019] Compared with traditional static penetration testing systems, the advantages of the static autonomous penetration testing system of this invention are:

[0020] (1) Traditional static cone penetration testing systems require the installation of self-weight or anchor-type reaction devices on the ground surface, which causes significant disturbance to the surrounding environment. However, the autonomous penetration system of this invention is designed based on the principles of razor clams burrowing into sand and earthworms moving. The upper expansion device 3, the loading device 2, and the lower expansion and contraction device 4 are designed. The upper expansion device 3 and the lower expansion and contraction device 4 can provide reaction force to the loading device 2 through the rock and soil itself. Therefore, it is not necessary to install a large and heavy reaction device on the ground surface. It can be used in deep sea, deep space and other locations that are difficult for humans and large machinery to reach, which greatly expands the site applicability of static cone penetration tests.

[0021] (2) Traditional static cone penetration testing systems require a series of probes connected to the upper part of the probe. The loading device inserts the probe into the soil through the probes. The friction between the probes and the surrounding soil greatly increases the penetration resistance. The deeper the penetration, the greater the friction between the probes and the soil, and the greater the penetration resistance. However, the penetration system designed in this invention uses the principle of the longitudinal and circular muscles of an earthworm to move forward by alternating contraction and relaxation. The loading device 2 is directly set above the static cone penetration probe 1. As the static cone penetration probe 1 penetrates downward, the loading device 2 will gradually move downward with the static cone penetration probe 1. Therefore, it is not necessary to set probes between the two, which can greatly reduce the penetration force required to penetrate to the same depth, or allow the static cone penetration probe 1 to penetrate deeper into the soil with the same penetration force.

[0022] (3) In traditional static cone penetration testing systems, the loading device and reaction device are fixed on the ground surface. However, in the autonomous penetration system of this invention, the loading device 2, the upper expansion device 3, and the lower contraction device 4 can gradually move downwards as the static cone probe 1 penetrates. When the loading device 2 extends, the upper expansion device 3 remains stationary, while the lower contraction device 4 and the static cone probe 1 move downwards; when the loading device 2 contracts, the lower contraction device 4 and the static cone probe 1 remain stationary, while the upper expansion device 3 moves downwards. By continuously repeating this process, the static cone probe 1 can gradually penetrate to the specified depth.

[0023] (4) Traditional static cone penetration testing systems can only allow the probe rod and probe to penetrate vertically into the soil. However, the autonomous penetration system of this invention can change the angle of the probe at any time during penetration, allowing the probe to penetrate the soil in any direction. The loading device 2 is equipped with four piston rods 10. When the extension amplitude of the four piston rods 10 is the same, the penetration direction remains unchanged. When the extension amplitudes of the four piston rods 10 are different, the penetration direction of the static cone penetration probe 1 can be changed, such as... Figure 9 As shown, (a) shows a schematic diagram of the static penetration probe 1 turning, and (b) shows the extension of each piston rod 10 in the loading device when the probe turns. Figure 10In the figure, (a) shows the appearance of the loading device after the piston rod is extended, (b) shows the appearance of the loading device after the piston rod is retracted, and (c) shows the appearance of the loading device when the static penetrating probe is turned and penetrated due to the different extension amplitudes of each piston rod in the loading device. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the static cone penetration autonomous penetration system of the present invention, wherein (a) is an external view and (b) is a partial sectional view;

[0025] Figure 2 yes Figure 1 The diagram shows the penetration process of the static penetrating autonomous penetrating system, where (a) is the initial state, (b) the upper part provides the reaction force, (c) the probe penetrates downward, (d) the lower part provides the reaction force, (e) the loading device retracts, and (f) the stage penetration is completed.

[0026] Figure 3 This is a schematic diagram of the contraction and expansion states of the upper expansion device, where (a) is the contraction state of the elastic membrane 15 and (b) is the expansion state of the elastic membrane 15.

[0027] Figure 4 This is a schematic diagram of the extension and retraction states of the loading device, where (a) is the extension state of the piston rod 10 and (b) is the retraction state of the piston rod 10.

[0028] Figure 5 This is a schematic diagram of the retracted and extended states of the lower telescopic device, where (a) is the retracted state of the rotatable telescopic metal sheet 17 and (b) is the extended state of the rotatable telescopic metal sheet 17.

[0029] Figure 6 This is a bottom view of the loading device base 5;

[0030] Figure 7 This is a simplified schematic diagram of the transmission and actuator mechanism that drives the metal blades to rotate and expand / contract in this invention;

[0031] Figure 8 This is a schematic elevation view of the connection relationship between the metal blade and related components in this invention;

[0032] Figure 9 This is a diagram showing the rotation of the static cone penetrometer probe and a partial enlargement. (a) is a schematic diagram of the rotation of the static cone penetrometer probe 1, and (b) is a schematic diagram of the extension of each piston rod 10 in the loading device when the probe rotates.

[0033] Figure 10This is a three-dimensional schematic diagram of the extension, retraction, and turning of the loading device in the static penetrating autonomous penetration system of the present invention. In this diagram, (a) is the piston rod extension state, (b) is the piston rod retraction state, and (c) is the state in which the static penetrating probe turns to penetrate due to the different extension amplitudes of all piston rods.

[0034] In the picture:

[0035] 1-Static cone penetration test probe; 2-Loading device; 3-Upper expansion device

[0036] 4-Lower expansion and contraction device; 5-Loading device base; 6-Loading device top plate

[0037] 7-Loading device side wall; 8-Hydraulic cylinder; 9-Piston

[0038] 10-Piston rod 11-Expansion device base 12-Expansion device top plate

[0039] 13-Hollow cylindrical tube 14-Water-permeable hole 15-Elastic membrane

[0040] 16-Central pivot 17-Metal blade 18-Fixing rod

[0041] 19-Water injection hole; 20-Slider; 21-Hinge.

[0042] 22-Connecting rod 23-Linear groove 24-Bearing

[0043] 25-Servo motor 26-Steel pipe 27-Hinge Detailed Implementation

[0044] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the following embodiments are by no means intended to limit the present invention.

[0045] This invention proposes a biomimetic-based static cone penetration system, comprising a controller, an upper expansion device 3, a loading device 2, a lower telescoping device 4, and a static cone penetration probe 1. The diameters of the upper expansion device 3, the loading device 2, and the lower telescoping device 4 are consistent with the diameter of the rod portion of the static cone penetration probe 1. Figure 1 and Figure 2 As shown. The upper expansion device 3 can expand and compress with the surrounding soil to provide a reaction force when the loading device 2 extends, and the lower contraction device 4 can expand into the soil to provide a reaction force when the loading device 2 contracts. Therefore, this penetration system provides a reaction force through the surrounding soil itself (hence the name "autonomous penetration system"), and does not require a large reaction force device to be installed on the ground surface to penetrate the static cone penetrator 1 into the soil.

[0046] The upper expansion device 3 includes an expansion device housing, which is composed of an expansion device base 11, an expansion device sidewall, and an expansion device top plate 12. The expansion device top plate 12 is provided with a water injection hole 19. The expansion device sidewall includes a hollow cylindrical tube 13, and the wall of the hollow cylindrical tube 13 is provided with a water permeable hole 14. The hollow cylindrical tube 13 is surrounded by an elastic membrane 15. The upper and lower ends of the hollow cylindrical tube 13 are fixedly connected to the expansion device base 11 and the expansion device top plate 12, respectively. The elastic membrane... The upper and lower ends of 15 are respectively sealed to the base 11 and the top plate 12 of the expansion device; when the upper expansion device 3 needs to provide reaction force, pressurized water is injected into the hollow cylindrical cylinder 13 through the injection hole 19 via the water injection pipe. The pressurized water is injected into the elastic membrane 15 through the water permeable hole 14, causing the elastic membrane 15 to expand and compress the surrounding soil, thereby generating a large normal pressure and tangential friction between the elastic membrane 15 and the surrounding soil. The tangential friction provides a reaction force when the loading device 2 extends, causing the static penetration probe 1 to penetrate downward into the soil. Figure 2 and Figure 3 As shown. When it is not necessary to provide a reaction force at the top of the loading device 2, the water pressure can be reduced to allow the elastic membrane 15 to return to its original state. Figure 3 In the image, (a) shows the elastic membrane 15 in its initial contracted state, and (b) shows the state of the elastic membrane 15 after pressurized water is injected into the hollow cylindrical tube 13.

[0047] The loading device 2 includes a loading device housing, which is composed of a loading device base 5, a loading device sidewall 7, and a loading device top plate 6. The loading device sidewall 7 is made of a circumferentially rigid and axially extensible material. Four sets of hydraulic loading units are arranged symmetrically front-to-back and left-to-right between the loading device base 5 and the loading device top plate 6. Each hydraulic loading unit includes a hydraulic cylinder 8, a piston 9, and a piston rod 10. The extension of the piston rod 10 allows the static cone penetrating probe 1 to penetrate the soil, and the shortening of the piston rod 10 allows the penetration system to gradually move downwards following the static cone penetrating probe 1. Furthermore, by controlling the extension range of the four piston rods 10 in the loading device 2, the penetration direction of the static cone penetrating probe 1 can be changed. Due to the material properties of the loading device sidewall 7, it can extend or shorten in accordance with the extension or shortening of the piston rod 10. The loading device 2 allows the static cone penetrating probe 1 to penetrate vertically into the soil or obliquely into the soil at any angle, such as... Figure 4 , Figure 9 and Figure 10 As shown. Figure 4In the diagram, (a) shows the extended state of the piston rod 10, and (b) shows the retracted state of the piston rod 10. When the piston rod 10 is extended, the top plate 6 of the loading device remains stationary, and the base 5 of the loading device moves downward, thereby allowing the static cone penetrating probe 1 to penetrate into the soil. When the piston rod 10 is retracted, the base 5 of the loading device remains stationary, and the top plate 6 of the loading device moves downward, causing the upper expansion device 3 to move downward. The side wall 7 of the loading device is made of a circumferentially rigid, axially extensible material. When the piston rod 10 is extended, the side wall 7 of the loading device extends axially; when the piston rod 10 is retracted, the side wall 7 of the loading device retracts axially.

[0048] The expansion device base 11 and the loading device top plate 6 are fixedly connected; a steel pipe 26 runs from the expansion device top plate 12 through the hollow cylindrical tube 13 and the expansion device base 11 to the loading device top plate 6, and the hydraulic pipeline of the hydraulic cylinder 8 is externally connected to the hydraulic pump through the steel pipe 26, such as... Figure 1 As shown.

[0049] The loading device base 5 has a bearing hole 24 at the center of its bottom surface, and six radially arranged linear grooves 23 are provided around the bearing hole. Figure 6 As shown.

[0050] like Figure 5 As shown, the lower telescoping device 4 includes six metal blades 17 and a central rotating shaft 16 driven by a servo motor 25. A bearing is provided on the top plate of the static cone penetrometer 1. Both ends of the central rotating shaft 16 are supported by bearings between the loading device base 5 and the top plate of the static cone penetrometer 1. A rotating arm is fixed to the central rotating shaft 16. The rotating arm includes six fixed rods 18, one end of which is fixed to the rotating shaft 16. The six fixed rods 18 and the six metal blades 17 are arranged radially. A transmission and actuation mechanism is provided one-to-one between the six fixed rods 18 and the six metal blades 17, such as... Figure 7 and Figure 8As shown, the transmission and execution mechanism includes a connecting rod 22. One end of the connecting rod 22 is hinged to the other end of the fixed rod 18 via a hinge pin 21. The other end of the connecting rod 22 is hinged to a slider 20 via a hinge 27. The slider 20 is embedded in the linear slide groove 23 and slides in cooperation with the linear slide groove 23. Each metal blade 17 is hinged to the hinge pin 21 and hinge 27 in the same transmission and execution mechanism. The servo motor 25 is controlled and driven to rotate 60° forward or backward. The central rotating shaft 16 drives all metal blades 17 to rotate synchronously through the transmission and execution mechanism and to expand and contract radially along the central rotating shaft 16. After driving the servo motor 25, the rotating arm frame rotates synchronously under the drive of the central rotating shaft 16. The fixed rod 18 pulls the connecting rod 22 in the transmission and execution mechanism, causing the hinge 27 to move closer to or away from the central rotating shaft 16, thereby causing the metal blades 17 to expand and retract in their plane. When a reaction force is needed at the bottom of the loading device 2, the metal blade 17 can be extended into the surrounding soil via the central rotating shaft 16, the fixed rod 18, and the transmission and actuator mechanisms. This allows the lower retraction device 4 and the static cone penetrometer 1 to remain stationary when the piston rod 10 is shortened. The bearing capacity of the soil above provides a reaction force to the loading device 2 as it shortens, causing the penetration system to gradually move downwards following the downward penetration of the static cone penetrometer 1. When a downward reaction force is no longer needed at the bottom of the loading device 2, the metal blade 17 can be retracted back to its original state. Figure 5 In the image, (a) shows the retracted state of the metal blade 17, and (b) shows the unfolded state of the metal blade 17. Since the six metal blades 17 are arranged radially at equal central angles, the rotation angle of the servo motor 25 in both forward and reverse directions is 60°.

[0051] In this invention, the servo motor 25, the hydraulic pump, and the water injection pipe are all connected to the controller.

[0052] In this embodiment, the static cone penetration probe 1 is a commercially available instrument, and the probe contains a cone tip resistance sensor, a side wall friction sensor, a pore water pressure sensor, and an inclinometer, all of which are connected to the controller.

[0053] The present invention is a biomimetic static cone penetration test autonomous penetration system that can allow the static cone penetration test probe 1 to penetrate vertically into the soil, or allow the static cone penetration test probe 1 to gradually turn during the penetration process, so that the probe can penetrate into the soil in any direction.

[0054] The static cone penetration test system of the present invention can be used to conduct static cone penetration tests. The main steps are as follows:

[0055] 1) Since the upper expansion device 3 and the lower contraction device 4 can only provide reaction force to the loading device 2 in soil at a certain depth, the static penetration probe 1 is first placed in the soil at a depth of about 1m from the ground surface by pre-drilling or self-drilling.

[0056] 2) Pressurized water is injected into the hollow cylindrical tube 13 of the upper expansion device 3 through the water injection hole 19. As the water pressure increases, the water will exert pressure on the elastic membrane 15 through the permeable hole 14. The elastic membrane 15 gradually expands outward and squeezes the surrounding soil. The normal pressure and tangential friction between the elastic membrane 15 and the soil gradually increase, thereby providing a reaction force for the downward penetration of the static cone penetration probe 1. As the penetration depth increases, the required penetration force also increases. The magnitude of the water pressure acting on the elastic membrane can be determined according to the required penetration force.

[0057] 3) By controlling the hydraulic pressure in the hydraulic cylinder 8, the piston rod 10 in the loading device 2 is extended. The side wall 7 of the loading device is extended accordingly as the piston rod 10 is extended, that is, the length of the entire loading device 2 will increase. At this time, the upper expansion device 3 remains stationary, so the static penetration probe 1 penetrates downward into the lower soil.

[0058] 4) To change the penetration direction of the static cone penetrometer 1, the extension amplitudes of the four piston rods 10 need to be different. When the extension amplitude of one piston rod is greater than that of the other piston rod, the static cone penetrometer 1 will deviate towards the side with the smaller extension amplitude. To keep the penetration direction of the static cone penetrometer 1 unchanged, the extension amplitudes of the four piston rods 10 should be the same.

[0059] 5) When the piston rod extends to its maximum extent, reduce the water pressure in the upper expansion device 3 so that the elastic membrane 15 contracts back to its initial state, and the normal pressure and tangential friction between the elastic membrane 15 and the soil are also reduced to their initial values.

[0060] 6) The drive servo motor 25 drives the fixed rod 18 fixed to it through the central rotating shaft 16, and through the transmission and execution mechanism, the six metal blades 17 are simultaneously deployed into the surrounding soil, thereby providing a reaction force for the downward movement of the upper expansion device 3.

[0061] 7) As the piston rod 10 in the loading device 2 shortens, the side wall 7 of the loading device also shortens accordingly, meaning the overall length of the loading device 2 decreases. At this time, the lower expansion / contraction device 4 and the static penetrometer 1 remain stationary, and the upper expansion device 3 moves downwards. Since the frictional force that the upper expansion device 3 needs to overcome to move downwards is usually less than the penetration force required for the static penetrometer 1 to penetrate downwards, the reaction force that the lower expansion / contraction device 4 needs to provide is usually less than the reaction force that the upper expansion device 3 needs to provide.

[0062] 8) When the piston rod 10 is shortened to the initial state, the servo motor 25 is reversed, which drives the fixed rod 18 fixed thereto through the central rotating shaft 16, and through the transmission and actuator mechanism, the six metal blades 17 are simultaneously retracted to the initial state.

[0063] At this point, one penetration operation is completed, and the entire penetration system returns to the initial state of step 1). However, the static cone penetration probe 1 has penetrated a certain distance into the deep soil (the distance depends on the elongation of the loading device 2), and the entire penetration system also moves downward a certain distance along with the static cone penetration probe 1.

[0064] 9) Repeat steps 2) to 8) to gradually penetrate the static cone penetration probe 1 to the specified depth. During the penetration process, the controller records the changes in cone tip resistance, side wall friction and pore water pressure with depth in real time, which are used to estimate the physical and mechanical properties of each soil layer.

[0065] 10) After penetrating to the designated depth, end the downward penetration test, gradually change the penetration direction of the static cone penetrator 1 so that it penetrates vertically upward to the ground surface, and then retrieve the static cone penetrator 1. Then retrieve the pipeline for injecting water into the water injection hole 19 and the pipeline connecting the loading device 2, as well as other components, to complete the entire test process.

[0066] Although the present invention has been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many improvements and modifications under the guidance of the present invention without departing from the spirit of the present invention, such as changing the structure of the upper expansion device and the lower contraction device, changing the loading method of the loading device, etc., all of which are within the protection scope of the present invention.

Claims

1. A biomimetic-based static penetrating autonomous penetration system, comprising a controller, an upper expansion device (3), a loading device (2), a lower expansion and contraction device (4), and a static penetrating probe (1), characterized in that, The upper expansion device (3) includes an expansion device housing, which is composed of an expansion device base (11), an expansion device sidewall, and an expansion device top plate (12). The expansion device top plate (12) is provided with a water injection hole (19). The expansion device sidewall includes a hollow cylindrical tube (13). The hollow cylindrical tube (13) has a water permeable hole (14) on its wall. The hollow cylindrical tube (13) is covered with an elastic membrane (15). The upper and lower ends of the hollow cylindrical tube (13) are fixedly connected to the expansion device base (11) and the expansion device top plate (12) respectively. The upper and lower ends of the elastic membrane (15) are sealed to the expansion device base (11) and the expansion device top plate (12) respectively. When the upper expansion device (3) needs to provide a reaction force, pressurized water is injected into the hollow cylindrical tube (13) through the water injection hole (19). The pressurized water is filled into the elastic membrane (15) through the water permeable hole (14). The loading device (2) includes a loading device housing, which is composed of a loading device base (5), a loading device side wall (7) and a loading device top plate (6). The loading device side wall (7) is made of a material that is circumferentially rigid and axially extensible. Four sets of hydraulic loading units are respectively arranged between the loading device base (5) and the loading device top plate (6) in a front-to-back symmetrical and left-to-right symmetrical manner. Each set of hydraulic loading units includes a hydraulic cylinder (8), a piston (9) and a piston rod (10). The expansion device base (11) and the loading device top plate (6) are fixedly connected; a steel pipe (26) is provided from the expansion device top plate (12) through the hollow cylindrical tube (13) and the expansion device base (11) to the loading device top plate (6), and the hydraulic pipeline of the hydraulic cylinder (8) is connected to the hydraulic pump through the steel pipe (26). The loading device base (5) has a bearing hole (24) at the center of its bottom surface, and six linear grooves (23) arranged radially around the bearing hole. The lower telescopic device (4) includes six metal blades (17) and a central rotating shaft (16) driven by a servo motor (25). A rotating arm is fixed on the central rotating shaft (16), and the rotating arm includes six fixed rods (18). One end of each fixed rod (18) is fixed to the central rotating shaft (16). A transmission and execution mechanism is provided between each of the six fixed rods (18) and the six metal blades (17). The transmission and execution mechanism includes a connecting rod (22). One end of the connecting rod (22) is hinged to the other end of the fixed rod (18) through a hinge pin (21). Next, the other end of the connecting rod (22) is hinged to a slider (20) via a hinge (27). The slider (20) is embedded in the linear slide groove (23) and slides in cooperation with the linear slide groove (23). Each metal blade (17) is hinged to the hinge shaft (21) and the hinge (27) in the same transmission and execution mechanism. The servo motor (25) is controlled and driven to rotate forward or backward by 60°. The central rotating shaft (16) drives all metal blades (17) to rotate synchronously through the transmission and execution mechanism and to expand and contract along the radial direction of the central rotating shaft (16). The static cone penetration probe (1) contains a cone tip resistance sensor, a side wall friction sensor, a pore water pressure sensor, and an inclination sensor, all of which are connected to the controller; the servo motor (25), the hydraulic pump, and the water injection pipe are all connected to the controller.

2. The biomimetic-based static probing autonomous penetration system according to claim 1, characterized in that, The six fixed rods (18) and the six metal blades (17) are arranged radially.

3. The static cone penetration autonomous penetration system according to claim 1, characterized in that, After the servo motor (25) is driven, the rotating arm rotates synchronously under the drive of the central rotating shaft (16). The fixed rod (18) pulls the connecting rod (22) in the transmission and execution mechanism, so that the hinge (27) moves closer to or away from the central rotating shaft (16), thereby driving the metal blade (17) to unfold and retract in its plane.

4. The biomimetic-based static probing autonomous penetration system according to claim 1, characterized in that, The top plate of the static cone penetrometer (1) is provided with a bearing, and the two ends of the central rotating shaft (16) are respectively supported by the bearing between the loading device base (5) and the top plate of the static cone penetrometer (1).

5. The static cone penetration autonomous penetration system according to claim 1, characterized in that, By controlling the extension of the four piston rods (10) in the loading device (2), the penetration direction of the static penetration probe (1) can be changed.

6. The static cone penetration autonomous penetration system according to claim 1, characterized in that, The wires of the servo motor (25) are connected to the power source through the steel pipe (26).

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