A cone heavy dynamic penetration test hole wall in-situ shear testing device

Abstract

The application discloses a hole wall in-situ shearing testing device for a conical heavy dynamic penetration test, and relates to the technical field of geological exploration equipment. The rack is provided with a shearing testing assembly, a penetration assembly and a power piece, and is further provided with a hole forming assembly. The cutter plate is provided with a plurality of blades, and the hinge joints of the blades are fixedly connected with soft bags. The soft bags are filled with fillers. The driving piece is used for changing the volume fraction of at least one kind of filler in the soft bags. The fillers are used for limiting the rotation of the hinge joints of the blades. According to the deformation amount, the influence degree of the soft bags at different depths on the shock wave is judged. The soft bags with a deformation amount less than a set value are phase changed from a non-blocking state to an over-blocking state, so as to reduce the interference of the soil disturbed by the dynamic penetration on the accuracy of the in-situ shearing test result.

Description

Technical Field

[0001] This invention relates to the field of geological exploration equipment technology, and in particular to an in-situ shear testing device for borehole walls in a heavy-duty cone penetration test. Background Technology

[0002] In-situ testing techniques in geotechnical engineering are crucial for obtaining soil mechanical parameters and evaluating foundation bearing capacity. Among these, the cone penetration test (CPPT) is widely used in conventional geological exploration. It indirectly assesses soil density and strength characteristics by recording the penetration resistance of a cone probe struck by a standard falling hammer, offering advantages such as speed, economy, and the ability to continuously acquire deep information. To obtain more direct and reliable soil mechanical parameters, after the initial penetration test, more refined in-situ shear tests are often conducted at the same location. These tests utilize instruments such as vane shear testers, lateral shear testers, or push shear testers, applying shear force to the soil around the borehole wall to determine shear strength.

[0003] In this process, the follow-up of casing is particularly important. Without casing or with poor casing follow-up, especially in loose strata or below the groundwater level, traditional penetration tests are prone to borehole wall collapse and diameter reduction. This not only affects the depth and data continuity of the penetration test but also directly restricts the feasibility of subsequent in-situ shear tests. Casing effectively maintains borehole wall stability, provides the necessary structural boundary for the test, and effectively avoids introducing new errors into the dynamic penetration test results due to borehole wall instability.

[0004] However, this type of technology has a significant drawback: dynamic penetration testing itself disturbs the soil surrounding the formed penetration hole, altering its original structure and stress state, thus affecting the accuracy of subsequent in-situ shear test results. In existing technologies, shear tests are often conducted at a certain distance laterally to the penetration hole (outside the "disturbance zone" estimated based on experience or theory) in an attempt to avoid the main disturbance area. However, the extent of the "disturbance zone" is difficult to define precisely due to factors such as soil properties, penetration energy, and groundwater. This method essentially still relies on empirical judgment, making the accuracy of the final data highly dependent on the operator's professional competence, and also increasing additional drilling costs and workload.

[0005] Meanwhile, in recent years, a new approach has been developed for solving the aforementioned problems: a smart material based on the principle of "blocked phase change"—the blocked phase change sandwich structure. In Zeng Xiangjing's paper, "Research on the Stress Mechanism of Blocked Phase Change Sandwich Structures," it is mentioned that such structures, under normal conditions (non-blocked state), "can freely bend and shrink to meet the structural shape requirements of different scenarios," exhibiting extremely high shape adaptability. However, when external control (such as vacuum negative pressure) is applied to trigger the blocked phase change, its mechanical properties undergo a dramatic transformation. As shown in the comparative verification in the paper, "under the principle of consistent material usage, compared with the honeycomb configuration, the corrugated configuration has a 30% higher ultimate bearing capacity, and higher stiffness and yield strength in the elastic stage." This means that through reasonable material and structural design, the blocked phase change sandwich structure can achieve a controllable and rapid transition from flexibility to high stiffness, providing a material basis for constructing adaptive, high-rigidity test interfaces in disturbed soil. Summary of the Invention

[0006] The purpose of this invention is to provide an in-situ shear testing device for borehole walls in heavy-duty cone penetration tests, so as to solve the above-mentioned problems.

[0007] This invention is achieved through the following technical solution: A borehole wall in-situ shear testing device for a heavy-duty cone penetration test includes a frame on which a shear testing component, a penetration component, and a power component are mounted. The penetration component is used to penetrate the soil, and the shear testing component is used to obtain the shear strength of the soil layer. The power component is used to provide gravitational potential energy to the penetration component and drive the shear testing component to perform shear testing on the soil. A hole-forming component is also mounted on the frame. The hole-forming component includes a casing. The power component is also used to drive the casing to drill downwards. A cutting edge is provided on the side wall of the casing, and a driving component is provided above the cutting edge. The driving component is used to push the cutting edge to move downwards and to push the cutting edge to rotate away from the casing. The cutting edge includes several blades, and the blades are hinged to adjacent blades. A soft bladder is fixedly connected to the hinge of the blades. The soft bladder is filled with a filler material, and the soft bladder is used to restrict the relative movement of the filler material. The driving component is also used to change the volume fraction of at least one filler material in the soft bladder. The filler material is used to restrict the rotation of the hinge point of the blades. It also includes a control system, which is used to collect the deformation of the soft capsule sidewall and obtain the power transmission path of the power component. When the power component transmits power to the probing component, it determines the degree of impact of the shock wave on the soft capsule at different depths based on the deformation. When the power component transmits power to the shear test component, it controls the drive component to work based on the degree of impact of the shock wave on the soft capsule, causing the soft capsule with a deformation less than a set value to undergo a phase transition from a non-blocking state to a over-blocking state. After the phase transition is completed, it controls the drive component to push the blade plate to rotate until it reaches the limit position of the blade plate, thus completing the preparation of the test surface before the in-situ shear test and sending a prompt message to the user.

[0008] Furthermore, the shear test assembly includes a cross plate, the output end of the power component is coaxially connected to the cross plate, and the control system is also used to acquire the torque of the cross plate and output torque data to the user.

[0009] Furthermore, a groove is formed on the outer wall of the protective sleeve, through which the cutting blade slides in cooperation with the protective sleeve. This design utilizes the groove to effectively increase the stability of the cutting blade's movement, reducing the impact of the cutting blade wobbling and striking the protective sleeve during its movement, thus preventing blade wear and extending the device's lifespan.

[0010] Furthermore, the driving component includes a pump assembly and several chambers formed in the side wall of the casing. A piston is slidably fitted in each chamber, and the piston divides the chamber into a driving chamber and a driven chamber. The driving chamber is connected to the pump assembly. A rotating shaft is provided in the driven chamber. The rotating shaft is connected to the side wall of the driven chamber through a cylindrical joint. A housing is wrapped around the outside of the rotating shaft, and the inner side wall of the housing and the side wall of the rotating shaft form several fan-shaped cavities. All fan-shaped cavities are coaxially arranged with the rotating shaft. The rotating shaft is arranged on the side of the driven chamber axis closer to the axis of the casing. The fan-shaped cavities are used to generate torque on the rotating shaft. The housing is also used to cut off the communication between the driven chamber and the outside.

[0011] Furthermore, the shear test assembly also includes a support assembly on which an elastic steel diaphragm is mounted. The elastic steel diaphragm is used to apply a thrust to the soil layer. The power component is also used to change the relative position of the elastic steel diaphragm and the frame. The control system is also used to acquire the displacement of the center point and the internal air pressure of the elastic steel diaphragm when it applies a thrust to the soil layer, and to acquire the lateral stress of the elastic steel diaphragm when it pushes the soil layer based on the displacement of the center point and the internal air pressure, and to output the lateral stress data of the elastic steel diaphragm to the user.

[0012] Furthermore, the control system is also used to control the drive component to move into the soil layer through the blade plate, acquire the deformation of the first soft bladder that shows a deformation change, and after drilling, use the average value of the deformation of the soft bladder during the drilling process as a verification value, calculate the difference between the verification value and the lateral stress data at the corresponding depth, and when the difference exceeds a set threshold, determine that the lateral stress data is incorrect, and simultaneously alarm the user when outputting the lateral stress data to the user.

[0013] Furthermore, the filler includes a fibrous material, which is filled with a plurality of rigid particles. Compared to existing technologies, this design uses a fibrous material containing rigid particles as the filler. This design utilizes the fibrous material to constrain the rigid particles, allowing it to compress the particles and strengthen the force chain network between them when negative pressure is applied inside the soft capsule. This results in higher and more stable stiffness of the soft capsule in its blocked state. Furthermore, due to the constraint effect of the fibrous material on the rigid particles, even if the soft capsule ruptures during use, the rigid particles are less likely to leak out and pollute the in-situ soil. Simultaneously, the fibrous material can buffer direct wear between the rigid particles, reducing the breakage or deformation of particles due to friction during long-term use.

[0014] Furthermore, the protective sleeve has a positioning hole, which is used to position two adjacent protective sleeves at an angle.

[0015] Furthermore, both the driven cavity and the sector-shaped cavity are filled with transmission particles, and a two-way pressure relief valve is installed on the driven cavity. The transmission particles are used to transfer the kinetic energy of the piston to the housing. In this solution, the design of the transmission particles, compared with the previous solution that uses gas transmission to generate torque in the housing, allows the pressure applied by the piston to the driven cavity to be transmitted to the housing along the force transmission network formed by the transmission particles after compression. Compared with compressed gas transmission, this transmission method has less force loss after the transmission particles are compressed, thereby reducing the probability of the blade failing to excavate the soil. Moreover, due to the mechanical interlocking effect formed by the compression of the transmission particles, it can also prevent the blade from being squeezed and rotated in the opposite direction during the subsequent discharge of excavated soil, which would disturb the already formed test surface. In addition, this design has lower requirements for the air pressure in the driven cavity, effectively avoiding the safety hazards that may be caused by excessive air pressure in the driven cavity.

[0016] Furthermore, the outer wall of the shell has several holes for connecting the sector cavity and the driven cavity. An elastic ring is arranged in the hole to restrict the movement of the transmission particles along the hole under the action of gravity. In this solution, the design of the holes prevents the transmission particles from leaving the device from the sector cavity during the rotation of the shell, thereby avoiding in-situ soil pollution.

[0017] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. This invention, through the design of the blade and soft bladder, monitors and judges the range of soil disturbance during dynamic penetration testing. When in-situ shear testing is required, the disturbed soil is removed, helping operators reduce the impact of soil disturbance during dynamic penetration testing on the accuracy of subsequent in-situ shear testing. Compared with the existing technology where operators select a position next to the penetration hole to insert the shear test component after dynamic penetration testing, this solution can monitor the soil disturbance state during dynamic penetration testing. The soil disturbance range obtained is more targeted and accurate, and the obtained data is closer to the data of undisturbed in-situ soil. At the same time, the data acquisition is more objective, effectively reducing the bias caused by subjective inference, thus making the test results more scientific and rigorous. 2. This invention also utilizes the design of support rods and elastic steel diaphragms to achieve in-situ shear strength testing of strata at different depths by slightly adjusting the casing advance scheme. Compared with existing technologies, this scheme effectively increases the abundance of soil data that can be obtained in a single test, thereby helping operators to conduct a more complete and clear analysis of the soil mechanical properties at this location. At the same time, this scheme can also use the cutting edge plate to further reinforce the casing, reducing its tilting during dynamic penetration testing and thus preventing new errors introduced into the data obtained by dynamic penetration testing. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a front cross-sectional view of the casing in this invention; Figure 3 This is a top cross-sectional view of the casing in this invention; Figure 4 This is a schematic diagram of the shear test component in Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the shear test component in Embodiment 2 of the present invention; Figure 6 for Figure 2 Enlarged view of point A in the middle; Figure 7 for Figure 2 Enlarged view of point B in the middle; Figure 8 for Figure 2 A magnified view of point C in the middle.

[0019] The reference numerals in the attached figures represent: 1. Frame; 2. Diesel engine hydraulic pump station; 21. Hydraulic clamping cylinder; 3. Penetration assembly; 31. Counterweight; 32. Guide rod; 33. Probe rod; 34. Lifter; 35. Conical probe; 4. Casing; 41. Blade; 411. Blade blade; 412. Soft bladder; 413. Filler; 42. Drive component; 421. Housing; 422. Rotating shaft; 423. Sector cavity; 424. Transmission particle; 425. Piston; 426. Drive cavity; 427. Sector groove; 5. Shear test assembly; 51. Cross plate; 52. Push rod; 521. Push arm. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. The illustrative embodiments and descriptions of this invention are for illustrative purposes only and are not intended to limit the invention. It should be noted that this invention is already in the actual research and development stage.

[0021] Example 1 like Figures 1 to 8 As shown, this embodiment includes a frame 1, on which a shear testing component 5, a penetration testing component 3, and a power component are mounted. The penetration testing component 3 is used to penetrate the soil. The shear testing component 5 is used to obtain the shear strength of the soil layer. The power component is used to provide gravitational potential energy to the penetration testing component 3 and drive the shear testing component 5 to perform uniform linear motion. The shear testing component 5 includes a vane 51, and the output end of the power component is coaxially connected to the vane 51.

[0022] The probing assembly 3 includes a guide rod 32, which is fixedly connected to the frame 1 by bolts. A counterweight 31 is fitted on the guide rod 32, and a lifting device 34 is provided at the top of the counterweight 31. The lifting device 34 is installed on the frame 1. A probe rod 33 is detachably connected to the bottom of the guide rod 32 by threads, and a conical probe 35 is detachably connected to the bottom of the probe rod 33 by threads. The power unit includes a diesel engine hydraulic pump station 2. The output end of the diesel engine hydraulic pump station 2 is connected to a hydraulic clamping cylinder 21, several hydraulic motors, and several oil cylinders. The output end of the diesel engine hydraulic pump station 2 is provided with a solenoid valve. The hydraulic clamping cylinder 21, the hydraulic motors, and the oil cylinders are all installed on the frame 1. The output end of any one of the hydraulic motors is coaxially connected to the cross plate 51, and the output end of any one of the oil cylinders is fixedly connected to the lifting device 34 by bolts.

[0023] The frame 1 is also equipped with a drilling assembly, which includes a casing 4. The hydraulic clamping cylinder 21 clamps the side wall of the casing 4, and at least one cylinder's output end is fixedly connected to the hydraulic clamping cylinder 21 by bolts. The power component is also used to drive the casing 4 to drill downwards. A sliding groove is opened in the side wall of the casing 4, and a cutting edge 41 is slidably fitted onto the casing 4 through the sliding groove. The cutting edge 41 includes several cutting blades 411, and each cutting blade 411 is hinged to an adjacent cutting blade 411. A driving component 42 is installed on the sliding groove, and the driving component 42 is used to push the cutting edge 41 downwards and push the cutting edge. 41 rotates toward the axis of the casing 4. The driving component 42 includes a pump assembly and several chambers formed on the side wall of the casing 4. The pump assembly is an air pump. A piston 425 is slidably fitted in the chamber, and the piston 425 divides the chamber into a driving chamber 426 and a driven chamber. The driving chamber 426 communicates with the pump assembly. A rotating shaft 422 is provided in the driven chamber. The rotating shaft 422 is connected to the side wall of the driven chamber through a cylindrical joint. The outside of the rotating shaft 422 is wrapped with a housing 421, and the inner side wall of the housing 421 and the side wall of the rotating shaft 422 form several fan-shaped cavities 423. All cavities 423 are coaxially arranged with the rotating shaft 422. The outer wall of the housing 421 has several holes for connecting the sector-shaped cavities 423 to the driven cavity. The housing 421 also cuts off the connection between the driven cavity and the outside. The side wall of the driven cavity has a sector-shaped groove 427 for rotating the housing 421. Both the driven cavity and the sector-shaped cavities 423 are filled with transmission particles 424, and elastic rings are bonded and fixed inside the holes. The inner diameter of the elastic rings is slightly smaller than that of the transmission particles 424. The elastic rings restrict the transmission particles 424 from passing through the sector-shaped cavities 423 under gravity. Furthermore, a bidirectional pressure relief valve is installed on the driven cavity, and a soft bag 412 is fixedly connected to the hinge of the blade 411. The soft bag 412 is filled with a filler 413, which includes a fibrous material and contains several rigid particles. In other embodiments, a porous material filled with hard particles or a thin sheet material can also be used as the filler 413. The soft bag 412 is connected to an air pump, and an electrically controlled throttle valve is installed at the connection between the soft bag 412 and the air pump. The driving component 42 is used to change the volume fraction of at least one filler 413 in the soft bag 412. It also includes a control system, which comprises a communication module, a controller, several flow sensors, and several strain gauges. The communication module, diesel engine hydraulic pump station 2, solenoid valve, flow sensor, strain gauges, air pump, and electronically controlled throttle valve are connected to the controller via signals. Any one strain gauge is mounted on the cross plate 51 to acquire the torque generated when the cross plate 51 is subjected to resistance. The remaining strain gauges are mounted on the sidewalls of adjacent soft bladders 412 to acquire the deformation of the sidewalls of the soft bladders 412. Flow sensors are mounted at the output end of the diesel engine hydraulic pump station 2 to acquire flow information from each output end of the diesel engine hydraulic pump station 2. After acquiring the flow information, the controller determines the power based on the changes in the flow rate. The power transmission path of the component is as follows: when the power component transmits power to the probe component 3, the degree of impact of the shock wave on the soft bladder 412 at different depths is determined according to the deformation. When the power component transmits power to the shear test component 5, the drive component 42 is controlled to work according to the degree of impact of the shock wave on the soft bladder. The soft bladder 412 with a deformation less than a set value is phase-transformed from a non-blocked state to a over-blocked state. After the phase-transformation is completed, the air pump is controlled to push the blade 41 to rotate until it rotates to the limit position of the blade 41, thus completing the preparation of the test surface before the in-situ shear test. The communication module is then controlled to send a prompt message to the user. At the same time, the controller is also used to obtain the torque of the cross plate 51 and control the communication module to output torque data to the user.

[0024] The specific implementation method is as follows: When using this device, move the device to the area to be tested, then start the diesel engine hydraulic pump station 2 and open the solenoid valve at the corresponding position, so that the hydraulic clamping cylinder 21 works to clamp the upper half of the side wall of the protective cylinder 4. After clamping, the protective cylinder 4 is squeezed downward through the oil cylinder connected to it. During this process, when the oil cylinder moves to its limit position, the controller releases the clamping and fixing of the hydraulic clamping cylinder 21 on the protective cylinder 4 through the operation of the diesel engine hydraulic pump station 2 and the solenoid valve at the corresponding position. Then, the oil cylinder at the corresponding position is retracted. After the hydraulic clamping cylinder 21 is reset, the above steps are repeated to drive the protective cylinder 4.

[0025] Once the drilling depth has reached the set depth for power penetration testing, the operator immediately stops the diesel engine hydraulic pump station 2 from supplying power to the casing 4 and discharges the slag and soil inside the casing 4.

[0026] During the above process, the flow sensor works and continuously collects the flow at each output end of the diesel engine hydraulic pump station 2. The controller can determine the direction of the output power of the diesel engine hydraulic pump station 2 based on the flow changes at each output end. The controller can also determine the operation steps that the operator is performing based on the flow changes.

[0027] When the diesel engine hydraulic pump station 2 stops continuously supplying power to the casing 4 and then stops supplying power to any component, the controller determines that the casing 4 is installed. Subsequently, the controller controls the air pump to operate, pumping gas into the drive chamber 426, thereby pushing the cutting edge 41 downward into the soil. At the same time, the controller draws gas from the soft bag 412, causing the air pressure inside the soft bag 412 to drop. The filler 413 and the inner wall of the soft bag 412 are squeezed against each other, causing the filler 413 to gradually change from a non-blocking state to a over-blocking state. The hardness of the soft bag 412 increases accordingly, achieving the effect of pressing the hinge of the cutting edge 411. The limiting effect is that as the blade plate 41 moves downward, it is limited by the resistance of the soil. The blade plate 41 gradually deviates from the vertical direction of travel. As the stiffness of the soft bag 412 gradually increases during this process, the compressive pressure between the fillers 413 increases. Under the action of soil resistance, the soft bag 412 is more likely to be compressed and bend, and it is difficult to stretch. At this time, the blade 411 is more likely to rotate towards the side where the soft bag 412 is installed. As the blade plate 41 enters the soil, the blade 411 gradually rotates away from the axis of the casing 4 until the blade plate 41 reaches its limit position.

[0028] The controller then starts the air pump, which pumps gas into the soft bag 412 until the deformation determines that the soft bag 412 no longer compresses the filling material 413, and the protective sleeve 4 is installed.

[0029] The operator can then power the hammer 31 via the diesel engine hydraulic pump station 2 and the solenoid valve. The hammer 31 is pulled upward by the cylinder and the lifting device 34. After reaching the required test height, the hammer 31 is released by the lifting device 34, allowing it to fall freely along the guide rod 32 and strike the probe rod 33. This transfers the kinetic energy of the hammer 31 to the probe rod 33 and then along the probe rod 33 to the conical probe 35. The conical probe 35 then compresses the soil downward, causing it to compact and break, and finally penetrates the soil.

[0030] As the penetration test progresses, operators can continuously assess the geological structure based on the penetration parameters and the condition of the penetration borehole. When abnormalities occur in the penetration parameters or the condition of the penetration borehole, it often indicates a significant change in the mechanical properties of the soil layer in contact with the cone probe 35. For example, if the penetration parameters drop sharply and abruptly without any geological reason, after ruling out mechanical failures, it can be determined that the cone probe 35 is very likely suspended or has entered a soft soil layer. Water or mud may form a lubricating layer around the probe rod 33, causing the energy consumption transmitted from the device to the soil layer to decrease compared to the normal state. If the penetration parameters rise sharply and abruptly without any geological reason, the probe rod 33 is very likely to be stuck. Or, if the operators observe muddy water continuously gushing out of the penetration borehole, groundwater leakage is very likely to occur.

[0031] When the above situation occurs, the soil around the probe hole cannot maintain the stability of the probe hole. If the probe test continues, the data will be easily distorted due to the stability of the probe hole and the movement state of the probe rod 33. Moreover, when the stability of the probe hole decreases, safety accidents such as the collapse of the probe hole are also very likely to occur.

[0032] At this point, the operator uses the diesel engine hydraulic pump station 2 to withdraw the probe rod 33 from the probe hole, and restarts the air pump and the corresponding electric throttle valve to retract the blade 41. Since the soft bag 412 does not compress the filling material 413 at this time, the limiting effect of the soft bag 412 on the hinge point of the blade 41 is small. As the blade 41 retracts, after being resisted by the soil, the blade 411 rotates around its hinge point. This makes the retraction step of the blade 41 less disturbing to the soil, avoiding instability of the probe hole wall caused by this step. Then, the top of the casing 4 is connected to... Connect the casing 4 and extend the length of the original casing 4 (at this time, a conventional casing 4 of the same size without the blade 41 can be used), and ensure that the distance from the top of the top casing 4 to the bottom of the bottom casing 4 is the same as the depth of the current penetration test hole. Then repeat the above steps until the casing 4 is installed (that is, the blade 41 is inserted into the soil). Then the penetration test can continue. In the subsequent penetration test, the penetration test hole should be continuously monitored according to the penetration parameters and the state of the penetration test hole, and the penetration test hole should be supported in a timely manner.

[0033] During the aforementioned process, as the dynamic penetration test proceeds, the shock wave propagates through the soil and simultaneously reaches the soft capsule 412, causing it to deform. Furthermore, due to the downward-sloping arrangement of the blade plate 41, different soft capsules 412 are distributed in different directions and positions around the casing 4. This allows the different soft capsules 412 to reflect the soil disturbance at different depths and distances around the penetration hole to a certain extent, i.e., to reflect the volume of disturbed soil during the penetration of the probe rod 33 and the conical probe 35.

[0034] When an in-situ shear test is required at the probe hole location, the operator adjusts the opening and closing of the solenoid valve to allow the diesel engine hydraulic pump station 2 to supply power to the cross plate 51. At this time, the controller determines the power transmission direction of the diesel engine hydraulic pump station 2 based on the flow information returned by the flow sensor.

[0035] Subsequently, based on the disturbance range of the soil during the power penetration test, the controller selects the soft bladder 412 with a smaller disturbance. Using this soft bladder 412 as a reference, the controller utilizes an air pump and an electronically controlled throttle valve to extract gas from the soft bladder 412 and all the soft bladders 412 between it and the casing 4, causing the hardness of this portion of the soft bladder 412 to increase. Then, gas is continuously pumped into the drive chamber 426 via the air pump. Since the blade 41 has already moved to its limit (i.e., the housing 421 has moved to the end of the driven chamber, the position of the fan-shaped groove 427), it cannot move further downwards. With the drive... The air pressure inside cavity 426 rises. Under the action of air pressure, piston 425 compresses the gas inside the driven cavity. After reaching the threshold of the two-way pressure relief valve, the gas is discharged from the two-way pressure relief valve. This causes piston 425 to compress transmission particles 424. Some transmission particles 424 enter the sector cavity 423 through the hole, compressing the side wall of the sector cavity 423. This causes the housing 421 to generate torque. Since the housing 421 has moved to the position of sector groove 427 at this time, as the torque of the housing 421 is generated, the housing 421 rotates along the inner side wall of sector groove 427, which in turn causes the rotating shaft 422 and the blade plate 41 to rotate.

[0036] At this point, the increased hardness of the soft bladder 412 restricts the rotation of the hinge at its corresponding position, while the soft bladders 412 at other positions have lower hardness and are difficult to limit the hinge at their corresponding positions. This also causes the blade 411 to rotate due to soil resistance as the blade plate 41 rotates, making it difficult to damage the soil. As the blade plate 41 is retracted, the blade 411 not limited by the soft bladder 412 moves along the channel, while the blade 411 limited by the soft bladder 412 damages the soil, pushing the soil to the position below the casing 4, thereby exposing the in-situ soil at this depth that has not been disturbed by the probe test. Subsequently, the controller sends a prompt message to the user through the communication module.

[0037] At this point, the operator discharges the slag inside the casing 4 and continues to lower the cross plate 51 by adjusting the opening and closing of the solenoid valve, so that the cross plate 51 is inserted into the soil in place. After insertion, the solenoid valve can be adjusted again to allow the diesel engine hydraulic pump station 2 to supply power to the cross plate 51, so that it shears and destroys the soil in place. Based on the data obtained by the strain gauges installed on the cross plate 51, the torque of the soil shearing and destruction in place is obtained and transmitted back to the user through the communication module, thus completing the in-situ shear test.

[0038] During the dynamic penetration test, the soft capsule 412, positioned at different distances from the casing 4, deforms under the influence of the shock waves output by the conical probe 35. This deformation can, to a certain extent, reflect the soil disturbance caused by the conical penetration shock waves on the surrounding soil layer. Compared to the existing in-situ shear test, which requires operators to select based on experience to drill holes around the penetration hole before testing, this method obtains the soil disturbance range through the deformation of the soft capsule 412 with a certain degree of specificity and accuracy. This makes the test process less affected by the professional competence of the operators, the data acquisition more objective, and reduces the bias caused by subjective inference, thus making the test results more scientific and rigorous.

[0039] Furthermore, the design of the soft bladder 412 in this scheme allows the device to change the hardness of the soft bladder 412 at various locations via an air pump during subsequent in-situ shear tests. This ensures that during the subsequent rotation of the blade 41 by the controller via the pump assembly, only the most disturbed soft bladder 412 can overcome soil resistance and move the disturbed soil, while the remaining soft bladder 412 cannot effectively limit the hinge of the blade 411, making it difficult for that part of the blade 411 to move the undisturbed soil. This ensures that the undisturbed soil is exposed while reducing the volume of pores formed in the soil layer during the process, thereby reducing the risk of soil collapse during in-situ shearing.

[0040] Furthermore, since this solution uses the degree of disturbance of the soft bladder 412 as the standard for whether it needs to limit the hinge at its corresponding position, this solution does not need to rely on long-term data accumulation. That is, this solution does not require precise calibration and repeated verification during the movement and adjustment of the casing 4, which helps to simplify the complexity of the operation throughout the process and weaken the impact of the operator's operational standardization on the accuracy of data acquisition.

[0041] Furthermore, since the blade 41 of the casing 4 is kept inserted into the soil before the dynamic penetration test in the above steps, the casing 4 tilts due to the shock wave generated by the dynamic penetration test during the test, thus rubbing against the probe rod 33, which greatly reduces the probability of introducing new errors into the dynamic penetration test results.

[0042] Example 2 As attached Figure 5 As shown, the difference from the above embodiment is that: the protective sleeve 4 has a positioning hole, which is used to position the angle of two adjacent protective sleeves 4.

[0043] The shear test assembly 5 also includes a support assembly on which an elastic steel diaphragm is mounted. In this embodiment, the support assembly is a pusher. The elastic steel diaphragm is mounted at the end of the pusher rod 52 of the pusher. The elastic steel diaphragm is used to apply a pushing force to the soil layer. The elastic steel diaphragm is connected to an external air source through a pipeline. The power component is also used to change the relative position of the elastic steel diaphragm and the frame 1. The diesel engine hydraulic pump station 2 is connected to the pusher. The control system also includes an inductive displacement sensor and a pressure sensor. The inductive displacement sensor is mounted on the elastic steel diaphragm, and the pressure sensor is mounted in the pipeline that supplies gas to the elastic steel diaphragm. The inductive displacement sensor is used to obtain the center point displacement of the elastic steel diaphragm and is connected to the controller signal. The controller is also used to obtain the center point displacement and internal air pressure of the elastic steel diaphragm when it applies a pushing force to the soil layer, and obtain the lateral stress on the elastic steel diaphragm when it pushes the soil layer based on the center point displacement and internal air pressure, and control the communication module to output lateral stress data to the user.

[0044] The specific implementation method is as follows: When using this solution, during the power penetration process, the total length of the casing 4 is extended by connecting multiple casings 4, and the casing 4 is continuously pushed forward by the diesel engine hydraulic pump station 2.

[0045] Since the lengths of the casing 4 and the probe 33 are known, the depth of the soil layer or other abnormal strata can be calculated based on the penetration depth of the probe 33 when probing the aforementioned soft soil layer or other abnormal strata. Thus, when there are multiple abnormal strata at the test location and the extended portion of the casing 4 gradually reaches the depth of the abnormal strata, the air pump is controlled to work, driving the blade 41 corresponding to the casing 4 to move and push the blade 41 into the soil.

[0046] Since each time the length of the casing 4 is increased, the cutting plate 41 of the last casing 4 is inserted into the soil, when the cutting plate 41 of the casing 4 is pulled out from the soil layer at that depth, there is a channel formed by the movement of the cutting plate 41 in the soil layer. Even if the soil layer settles down under the action of gravity, the resistance of the soil layer that the subsequent cutting plate 41 needs to overcome when it is inserted into the soil layer at this position is smaller than the resistance that the cutting plate 41 needs to overcome when it is first inserted into the soil layer at this position.

[0047] Since the airbag does not create negative pressure inside the soft bag 412, the limiting effect of the soft bag 412 on the hinge of the blade 411 is small. Due to the resistance of the soil around the channel, the blade 411 rotates, allowing the blade plate 41 to enter along the channel, or only a small force is needed to push away the soil accumulated in the channel and enter the channel, completing the return of the blade plate 41 and the casing 4. After the blade plate 41 moves to the limit position, air can be pumped into the soft bag 412 again by the air pump, causing the soft bag 412 to expand to a state that does not compress the filling material 413, thus completing the installation of the casing 4 at this position.

[0048] Repeat the above steps until the heavy-duty cone penetration test is completed.

[0049] After the penetration test is completed, when an in-situ shear test is required at the location, the operator can install the push rod 52 onto the frame 1 according to the shear test component 5, and supply power to the push rod 52 by adjusting the opening and closing of the solenoid valve.

[0050] At this time, the controller controls the corresponding air pump to work according to the disturbance state of the soft bladder 412 on each casing 4 during the dynamic penetration test, so that the blade 41 pushes the disturbed soil to the lower position outside the casing 4, thereby exposing the in-situ soil at this depth that was not disturbed by the penetration test. Then the controller sends a prompt message to the user through the communication module.

[0051] At this point, the operator can slowly lift the casing 4 using the power unit, allowing the soil accumulated on the outer circumference of the casing 4 to enter the penetration hole, thereby exposing the soil that has not been disturbed by the power penetration test.

[0052] Since the depth selection for in-situ shear testing is often guided by engineering requirements, special strata (such as the soft soil layer mentioned above) can easily affect construction. In other words, in traditional in-situ shear testing, the depths with special support mentioned above need to be tested to obtain more comprehensive and accurate geological data.

[0053] In the above process, according to the depth of the abnormal stratum, when the casing 4 is raised to the depth of the abnormal stratum, the operator pushes the pusher into the probe hole by adjusting the opening and closing of the solenoid valve. When the end of the pusher arm 521 reaches the depth of the abnormal stratum, the operator drives the pusher to extend the pusher arm 521, so that the pusher arm 521 drives the elastic steel diaphragm to move radially towards the probe hole and enter the undisturbed soil. Then the operator can supply gas into the elastic steel diaphragm through an external air source, so that the elastic steel diaphragm expands radially along the probe hole, thereby applying a set thrust to the soil layer. At the same time, the inductive displacement sensor continuously obtains the displacement of the center point of the elastic steel diaphragm, and the air pressure sensor obtains the change of air pressure inside the elastic steel diaphragm. The controller performs the above operations sequentially according to the center point displacement until all key support positions are traversed. At the same time, the controller continuously obtains the lateral stress of the corresponding soil layer according to the center point displacement of the elastic steel diaphragm and its internal air pressure change, and transmits the lateral stress data back to the user through the communication module for the user to calculate the shear strength of the in-situ soil at each depth.

[0054] Compared to existing cone penetration test designs, this scheme, through the design of the cutting edge 41, allows the casing 4 to be positioned at the top of the penetration hole and in weak soil areas by extending the cutting edge 41. This further reduces the risk of the casing 4 becoming unstable due to vibrations generated during penetration testing when the device is facing loose and weak soil layers such as soft soil foundations, thus preventing the penetration hole from collapsing.

[0055] Furthermore, compared to the previous scheme, this scheme can further realize shear strength testing of abnormal strata at different depths, increase the richness of soil data that can be obtained in a single test, and significantly save the time cost required for testing.

[0056] This scheme, through the design of the soft capsule 412, locates and peels away the soil disturbed by the dynamic penetration test, and exposes the undisturbed soil more accurately. Compared with the traditional flat shovel lateral expansion test, this scheme has a certain degree of accuracy in locating the disturbed soil, thereby effectively reducing the impact of the disturbed soil on the accuracy of the in-situ shear test.

[0057] Meanwhile, the design of positioning holes in this scheme ensures that the positions of the blades 41 installed on adjacent casings 4 remain consistent during the connection process. This ensures that when the blades 41 are inserted into the soil during the subsequent installation of casings 4, they can enter the channel formed by the previous blade 41 in the soil. This effectively avoids the offset of the blades 41 on the two adjacent casings 4 due to misalignment during installation, which would make it difficult for the blades 41 to be inserted into the soil, or cause damage to multiple locations in the soil layer at that depth even if the blades 41 are inserted, thus significantly increasing the risk of collapse and instability of the soil layer at that depth.

[0058] Example 3 The difference from the above embodiment is that the controller is also used to control the drive member 42 to move into the soil layer through the blade 41, to obtain the deformation of the first soft bladder 412 that shows deformation change, and after drilling, to use the average value of the deformation of the soft bladder 412 during the drilling process as a verification value, to calculate the difference between the verification value and the lateral stress data at the corresponding depth, and to determine that the lateral stress data is incorrect when the difference exceeds a set threshold, and to simultaneously alarm the user when the control communication module outputs the lateral stress data to the user.

[0059] The specific implementation method is as follows: During the use of this solution, when the air pump pumps gas into the drive chamber 426, pushing the blade 41 to insert into the soil, the controller takes the first soft bladder 412 that shows deformation change as the reference, and continuously records all deformation data of the soft bladder 412 from the occurrence of deformation change to the blade 41 extending to the limit position, and calculates the average value of the data. Since the first soft bladder 412 that shows deformation change is selected as the reference, the soil on the path of the soft bladder 412 is only affected by the blade 411 at the end of the corresponding blade 41. The deformation of the sidewall of the soft capsule 412 caused by the soil pushing it is closer to the deformation caused by the soil pushing it in situ. Since the size, elastic modulus and other values ​​of the soft capsule 412 are known, and the deformation of its sidewall before entering the soil is known, the magnitude of the resistance it encounters when entering the soil can be calculated. Furthermore, since the soil on which the soft capsule 412 acts is closer to the soil in situ, the data obtained (i.e., the verification value) should also be closer to the lateral stress data obtained at this location through the elastic steel diaphragm. Therefore, the threshold of the difference between the two should be within a certain range.

[0060] If the difference between the two values ​​exceeds the set threshold, then one of the data has a large error. At this time, while transmitting the lateral stress data back to the user, an alarm will be triggered to prompt the user to check the data, thereby reducing the pollution of the overall dataset caused by data with large errors and affecting the user's judgment of the soil mechanical properties at that location.

[0061] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An in-situ shear testing device for a cone penetration test, comprising a frame (1), wherein a shear testing component (5), a penetration component (3), and a power component are mounted on the frame (1), the penetration component (3) being used to penetrate the soil, the shear testing component (5) being used to obtain the shear strength of the soil layer, and the power component being used to provide the penetration component (3) with gravitational potential energy and to drive the shear testing component (5) to perform shear testing on the soil, characterized in that: A drilling assembly is also installed on the frame (1). The drilling assembly includes a casing (4). The power unit is also used to drive the casing (4) to drill downwards. A cutting edge (41) is provided on the side wall of the casing (4), and a driving member (42) is provided above the cutting edge (41). The driving member (42) is used to push the cutting edge (41) to move downwards and to push the cutting edge (41) to rotate away from the casing (4). The cutting edge (41) includes a plurality of cutting blades (411), and the cutting blades (411) 411) is hinged to an adjacent blade (411), and a soft bag (412) is fixedly connected to the hinge of the blade (411). The soft bag (412) is filled with a filler (413). The soft bag (412) is used to restrict the relative movement of the filler (413). The driving member (42) is also used to change the volume fraction of at least one filler (413) in the soft bag (412). The filler (413) is used to restrict the rotation of the hinge point of the blade (411). It also includes a control system, which is used to collect the deformation of the sidewall of the soft capsule (412) and obtain the power transmission path of the power component. When the power component transmits power to the probe component (3), it determines the degree of impact of the shock wave on the soft capsule (412) at different depths based on the deformation. When the power component transmits power to the shear test component (5), it controls the drive component (42) to work based on the degree of impact of the shock wave on the soft capsule (412). It causes the soft capsule (412) with a deformation less than a set value to undergo a phase transition from a non-blocking state to a over-blocking state. After the phase transition is completed, it controls the drive component (42) to push the blade plate (41) to rotate until it rotates to the limit position of the blade plate (41). This completes the preparation of the test surface before the in-situ shear test and sends a prompt message to the user.

2. The in-situ shear testing device for borehole wall in a heavy-duty cone penetration test according to claim 1, characterized in that: The shear test assembly (5) includes a cross plate (51), the output end of the power component is coaxially connected to the cross plate (51), and the control system is also used to acquire the torque of the cross plate (51) and output torque data to the user.

3. The in-situ shear testing device for borehole wall in a heavy-duty cone penetration test according to claim 1, characterized in that: The outer wall of the sleeve (4) has a sliding groove, and the blade (41) slides in cooperation with the sleeve (4) through the sliding groove.

4. The in-situ shear testing device for borehole wall in a heavy-duty cone penetration test according to claim 1, characterized in that: The drive unit (42) includes a pump assembly and several chambers formed on the side wall of the casing (4). A piston (425) is slidably fitted in each chamber, and the piston (425) divides the chamber into a drive chamber (426) and a driven chamber. The drive chamber (426) is connected to the pump assembly. A rotating shaft (422) is provided in the driven chamber. The rotating shaft (422) is connected to the side wall of the driven chamber through a cylindrical joint, and the rotating shaft (422) is covered with a shell. The housing (421) has an inner wall and a rotating shaft (422) side wall that form a plurality of fan-shaped cavities (423). The fan-shaped cavities (423) are all coaxially arranged with the rotating shaft (422). The rotating shaft (422) is arranged on the side of the driven cavity axis close to the axis of the protective sleeve (4). The fan-shaped cavities (423) are used to generate torque on the rotating shaft (422). The housing (421) is also used to cut off the connection between the driven cavity and the outside.

5. The in-situ shear testing device for borehole wall in a heavy-duty cone penetration test according to claim 1, characterized in that: The shear test assembly (5) also includes a support assembly on which an elastic steel diaphragm is installed. The elastic steel diaphragm is used to apply a thrust to the soil layer. The power component is also used to change the relative position of the elastic steel diaphragm and the frame (1). The control system is also used to acquire the displacement of the center point and the internal air pressure of the elastic steel diaphragm when it applies a thrust to the soil layer, and to acquire the lateral stress of the elastic steel diaphragm when it pushes the soil layer based on the displacement of the center point and the internal air pressure, and to output the lateral stress data of the elastic steel diaphragm to the user.

6. The in-situ shear testing device for borehole wall in a heavy-duty cone penetration test according to claim 5, characterized in that: The control system is also used to control the drive component (42) to move into the soil layer through the blade (41), to obtain the deformation of the first soft bladder (412) that shows deformation change, and after drilling, to use the average value of the deformation of the soft bladder (412) during the drilling process as a verification value, to calculate the difference between the verification value and the lateral stress data at the corresponding depth, and to determine that the lateral stress data is wrong when the difference exceeds the set threshold, and to simultaneously alarm the user when outputting the lateral stress data to the user.

7. The in-situ shear testing device for borehole wall in a heavy-duty cone penetration test according to claim 1, characterized in that: The filler (413) comprises a fibrous material filled with a plurality of rigid particles.

8. The in-situ shear testing device for borehole wall in a heavy-duty cone penetration test according to claim 5, characterized in that: The protective sleeve (4) has a positioning hole, which is used to position the angle of two adjacent protective sleeves (4).

9. The in-situ shear testing device for borehole wall in a heavy-duty cone penetration test according to claim 4, characterized in that: Both the driven cavity and the sector cavity (423) are filled with transmission particles (424), which are used to transfer the kinetic energy of the piston (425) to the housing (421). A two-way pressure relief valve is also installed on the driven cavity.

10. The in-situ shear testing device for borehole wall in a heavy-duty cone penetration test according to claim 9, characterized in that: The outer wall of the housing (421) has several holes for connecting the sector cavity (423) with the driven cavity, and an elastic ring is arranged in the hole for restricting the movement of the transmission particle (424) along the hole under the action of gravity.

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