A helical plate load test device and method

Abstract

This invention discloses a spiral plate load testing device and method, belonging to the field of geological exploration technology. The device includes a spiral plate head, a force transmission rod, a pressure sensor, a displacement sensor, a self-drilling spinning mill, a reaction force assembly, and an intelligent analysis platform. The reaction force assembly provides test reaction force for the load test. The intelligent analysis platform controls the telescopic arm of the self-drilling spinning mill to move along the axis and rotate around the axis to provide power to the force transmission rod, pressure sensor, and spiral plate head. By setting a clamp at the bottom of the telescopic arm to provide a detachable connection between the telescopic arm and the force transmission rod, the telescopic arm can drive the force transmission rod, pressure sensor, and spiral plate head downward together during multiple reciprocating movements, which can send the spiral plate head into a deeper soil layer. During the load test, the hydraulic chamber of the self-drilling spinning mill can realize the staged loading or unloading of the spiral plate head, so that the pressure sensor and displacement sensor can collect the plate head pressure data and displacement data in real time and transmit them to the intelligent analysis platform.

Description

Technical Field

[0001] This invention belongs to the field of geological exploration technology, specifically relating to a spiral plate load testing device and method. Background Technology

[0002] In-situ testing is one of the most effective methods for accurately obtaining the physical and mechanical properties of soil and rock, and it has significant advantages over laboratory tests, model tests, numerical analysis and other methods.

[0003] Load testing is the most classic and direct in-situ testing method for reflecting the deformation law of soil and rock masses, including plate load testing and spiral plate load testing. For undisturbed soil, the maximum test depth for plate load testing is generally about 5m, and for spiral plate load testing it is about 10m. Conventional load testing is generally difficult to conduct in-situ tests on deep soil layers (20m and above), and conducting load tests on deeper soil layers often requires the assistance of excavators, drilling rigs, and other equipment, resulting in huge costs and greatly restricting the widespread application of load testing in geotechnical engineering. How to increase the test depth of load testing and achieve continuous testing in soil layers is a key issue for promoting the application of load testing in deep geotechnical engineering investigation. Summary of the Invention

[0004] In response to one or more of the above-mentioned defects or improvement needs of the existing technology, the present invention provides a spiral plate load testing device and method, which realizes automatic penetration of spiral plate load testing, solves the problem that traditional load testing is unable to carry out deep load testing due to factors such as the influence of strata and insufficient manual drilling capabilities, and greatly improves the test depth and engineering exploration depth of spiral plate load testing, which is suitable for in-situ testing and exploration of deep soil.

[0005] To achieve the above objectives, the present invention provides a spiral plate load testing device, which includes a spiral plate head, a force transmission rod, a pressure sensor, a displacement sensor, a self-drilling spinning machine, a reaction force assembly, and an intelligent analysis platform; The self-drilling spinning machine includes a first cylinder and a second cylinder arranged coaxially. The first cylinder has a first channel for accommodating the force transmission rod. A second channel is formed between the first cylinder and the second cylinder. A telescopic arm that can move axially and rotate around the axis is provided in the second channel. A clamp is provided at the bottom of the telescopic arm. The clamp can clamp or release the force transmission rod. The top surface of the telescopic arm and the second channel form a hydraulic cavity. A hydraulic sensor is correspondingly provided in the hydraulic cavity. The reaction force assembly is fixedly installed on the ground and is used to fix the self-drilling spinning machine during the test; The pressure sensor is disposed between the force transmission rod and the spiral plate head, and is used to measure the pressure on the spiral plate head during the test; the displacement sensor is disposed at the bottom of the second cylinder, and is used to measure the vertical displacement of the telescopic arm during the test. The intelligent analysis platform is connected to the hydraulic sensor, the pressure sensor, and the displacement sensor respectively, and is used to receive the oil pressure data of the hydraulic chamber, the pressure data of the plate head during the test, and the displacement data in real time, respectively. Based on the oil pressure data, the platform controls the oil pressure in the hydraulic chamber to make the telescopic arm move back and forth along the axis. The intelligent analysis platform is also wirelessly connected to the rotation drive device of the telescopic arm to control the telescopic arm to rotate around the axis.

[0006] As a further improvement of the present invention, the displacement sensor is a pull-wire type displacement sensor; a limiter is provided on the side of the clamp away from the force transmission rod, and one end of the limiter extends out of the outer side wall of the telescopic arm; The pull-wire displacement sensor can be connected to the limiter via a vertically extending pull wire, allowing the pull-wire displacement sensor to measure the vertical displacement of the telescopic arm during the test.

[0007] As a further improvement of the present invention, the pressure sensor is an electromagnetic pressure sensor, the spiral plate head is an electromagnetic spiral plate head, and an electromagnetic anchor is provided on the side of the pressure sensor facing the spiral plate head, which can attract the electromagnetic spiral plate head to the magnetic pressure sensor through electromagnetic action.

[0008] As a further improvement of the present invention, the force transmission rod includes a probe rod, or the force transmission rod includes multiple probe rods, with adjacent probe rods connected at their tops and bottoms respectively.

[0009] As a further improvement of the present invention, a signal transceiver is provided inside the probe rod; a signal sensor is provided on the side of the pressure sensor facing the force transmission rod, which can convert the pressure signal collected by the pressure sensor into a digital signal and transmit it to the intelligent analysis platform through several of the signal transceivers.

[0010] As a further improvement of the present invention, the length of the probe rod is 2 to 3 times the length of the telescopic arm.

[0011] As a further improvement of the present invention, a plurality of crossbeams are arranged radially at intervals on the outer side wall of the second cylinder; The reaction force assembly includes a bidirectional telescopic rod and a balance suspension beam. The bidirectional telescopic rod can connect one end of the crossbeam to one end of the balance suspension beam, and the other end of the balance suspension beam is fixedly installed on the ground by a threaded rod ground anchor.

[0012] As a further improvement of the present invention, four crossbeams are spaced apart and arranged at 90° along the radial direction of the second cylinder; and / or A variable speed rotary bearing is provided at the end of the balance beam away from the crossbeam, and the variable speed rotary bearing can drive the threaded rod ground anchor to rotate.

[0013] Another aspect of the present invention provides a method for testing the load on a spiral plate, which utilizes the aforementioned spiral plate load testing apparatus and includes the following steps: (1) Preparation S101: Level the test site and mark the test hole locations according to the test hole locations and surrounding terrain features; S102: Center and level the self-drilling spinning machine, fix the reaction force assembly on the ground, and connect the reaction force assembly to the self-drilling spinning machine; S103: Pass the force transmission rod through the first channel of the self-drilling spinneret and connect it in sequence to the pressure sensor and the spiral plate head. Debug the intelligent analysis platform, calibrate the preloaded spiral plate head, and ensure that the data signal can be transmitted normally. S104: The clamp clamps the force transmission rod, and the intelligent analysis platform controls the telescopic arm to slowly bring the spiral plate head into the soil at the set moving speed and rotation speed. When the telescopic arm moves downward to the maximum limit, the clamp releases the force transmission rod, and the intelligent analysis platform controls the telescopic arm to move upward to the set position. The clamp clamps the force transmission rod again, and the intelligent analysis platform further controls the telescopic arm to slowly bring the spiral plate head into the soil at the set moving speed and rotation speed. This cycle continues until the spiral plate head reaches the test soil layer point. (2) Load test S201: Zero the displacement sensor and pressure sensor, start the test, the intelligent analysis platform controls the oil pressure in the hydraulic chamber to perform graded loading, the pressure sensor and displacement sensor provide real-time feedback of the collected plate head pressure data and displacement data S, the intelligent analysis platform analyzes the collected plate head pressure data and displacement data and plots the QS curve; S202: After the loading test, the intelligent analysis platform controls the oil pressure in the hydraulic chamber to unload in stages. The pressure sensor and displacement sensor provide real-time feedback of the collected pressure and displacement data of the plate head. The intelligent analysis platform analyzes the collected pressure and displacement data of the plate head, plots the QS curve, and outputs the test report after the unloading test is completed.

[0014] As a further improvement to the present invention, the spiral plate load test method also includes the following process: (3) Continuous load test S301: After completing the previous set of load tests, repeat step S104 and continue to screw the auger head into the next test soil layer point of the test hole. S302: Repeat steps S201~S202; S303: Determine whether the test soil point is the last test soil point of the test borehole. If yes, the continuous load test ends; otherwise, return to step S301.

[0015] The aforementioned improved technical features can be combined with each other as long as they do not conflict with each other.

[0016] In summary, the beneficial effects of the above-described technical solutions conceived by this invention compared with the prior art include: (1) The spiral plate load testing device of the present invention includes a spiral plate head, a force transmission rod, a pressure sensor, a displacement sensor, a self-drilling spinning mill, a reaction force assembly, and an intelligent analysis platform. The reaction force assembly provides the test reaction force for the load test. The intelligent analysis platform controls the axial movement and rotation of the telescopic arm of the self-drilling spinning mill to provide power to the force transmission rod, pressure sensor, and spiral plate head. By providing a clamp at the bottom of the telescopic arm to provide a detachable connection between the telescopic arm and the force transmission rod, the telescopic arm can drive the force transmission rod, pressure sensor, and spiral plate head together when rotating and pressing down. The self-drilling spinning press advances downwards, then rises independently, using a clamp to re-clamp another part of the force transmission rod. The telescopic arm then drives the force transmission rod, pressure sensor, and spiral plate head to rotate downwards together. Through multiple back-and-forth movements of the telescopic arm, the force transmission rod, pressure sensor, and spiral plate head can be sent into deeper soil layers. During the load test phase, the hydraulic chamber of the self-drilling spinning press can also perform staged loading or unloading of the spiral plate head, allowing the pressure sensor and displacement sensor to collect pressure and displacement data of the plate head in real time and transmit them to the intelligent analysis platform, ultimately generating a test report on the intelligent analysis platform. The spiral plate load test device of this invention achieves automatic penetration of the spiral plate load test through a self-drilling spinning press, solving the problem that traditional load tests are unable to conduct deep load tests due to factors such as the influence of strata and insufficient manual drilling capabilities. This greatly improves the test depth and engineering exploration depth of the spiral plate load test, making it suitable for in-situ testing and exploration of deep soil.

[0017] (2) The spiral plate load testing device of the present invention also improves the force mode of the force transmission rod in the traditional load test by means of the clamp, which improves the overall stability of the structure, greatly reduces the problem of eccentric compression of the system, and improves the depth and accuracy of the spiral plate load test; through the integrated digital intelligent analysis platform, the automated operation of the spiral plate load test is realized. It can realize functions such as automatic penetration, continuous testing, intelligent loading, unloading, digital acquisition, long-distance wireless transmission, and intelligent analysis according to the operation instructions, which solves the problem that the traditional spiral plate load test is heavily dependent on manual operation, greatly improves the efficiency of the spiral plate load test, and reduces the test cost.

[0018] (3) The spiral plate load testing device of the present invention sets the force transmission rod in the form of multiple probes connected in sequence, so that several probes can form a force transmission rod of different lengths to adapt to load tests of different depths; by setting the pressure sensor as an electromagnetic pressure sensor and the spiral plate head as an electromagnetic spiral plate head, an electromagnetic anchor is set on the side of the pressure sensor facing the spiral plate head, and the electromagnetic spiral plate head is attracted to the magnetic pressure sensor by electromagnetic action, which can prevent the spiral plate head from falling off when rotating in the forward or reverse direction, so as to facilitate the recovery of the spiral plate head.

[0019] (4) The spiral plate load test method of the present invention uses a signal sensor and a signal transceiver to realize the wireless real-time transmission of spiral plate head pressure data. Through wireless real-time transmission, wire-type displacement sensor and compact force transmission structure, high-precision acquisition and measurement of test load and soil deformation are realized, which improves the accuracy of spiral plate load test.

[0020] (5) The spiral plate load test method of the present invention uses the above-mentioned spiral plate load test device to carry out load test, which greatly improves the engineering investigation depth of spiral plate load test. Through the integrated digital intelligent analysis platform, the automated operation of spiral plate load test is realized, which solves the problem that traditional spiral plate load test is heavily dependent on manual operation. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a cross-sectional view of the overall structure of the spiral plate load testing device in an embodiment of the present invention; Figure 2 This is a top view of the spiral plate load testing device in an embodiment of the present invention; Figure 3This is a schematic diagram of the structure of the self-drilling spinning mill in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the spiral plate head, pressure sensor, and probe in an embodiment of the present invention; Figure 5 This is a flowchart of the data acquisition process for the load test in an embodiment of the present invention.

[0023] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1. Spiral plate head; 2. Force transmission rod; 21. Probe rod; 22. Signal transceiver; 3. Pressure sensor; 31. Electromagnetic anchor; 32. Signal sensor; 4. Displacement sensor; 5. Self-drilling spinning machine; 51. First cylinder; 511. First channel; 52. Second cylinder; 521. Crossbeam; 53. Telescopic arm; 54. Clamp; 55. Hydraulic chamber; 56. Hydraulic sensor; 57. Limiter; 58. Guy wire; 6. Reaction assembly; 61. Bidirectional telescopic rod; 62. Balanced cantilever beam; 63. Threaded rod ground anchor; 64. Variable speed rotary bearing. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0025] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0027] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0028] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0029] Example: Please see Figures 1-4 The spiral plate load testing device in the preferred embodiment of the present invention includes a spiral plate head 1, a force transmission rod 2, a pressure sensor 3, a displacement sensor 4, a self-drilling spinning machine 5, a reaction force assembly 6, and an intelligent analysis platform.

[0030] Specifically, such as Figure 3 As shown, the self-drilling spinning machine 5 includes a first cylinder 51 and a second cylinder 52 arranged coaxially. The first cylinder 51 is provided with a first channel 511 that can accommodate the force transmission rod 2. A second channel is formed between the first cylinder 51 and the second cylinder 52. A telescopic arm 53 that can move axially and rotate around the axis is provided in the second channel. A clamp 54 is provided at the bottom end of the telescopic arm 53. The clamp 54 can clamp or release the force transmission rod 2. The top surface of the telescopic arm 53 and the second channel form a hydraulic cavity 55. A hydraulic sensor 56 is correspondingly provided in the hydraulic cavity 55.

[0031] Furthermore, the reaction component 6 is fixedly installed on the ground to fix the self-drilling spinneret 5 during the test; the pressure sensor 3 is set between the force transmission rod 2 and the spiral plate head 1 to measure the pressure on the spiral plate head 1 during the test; the displacement sensor 4 is set at the bottom of the second cylinder 52 to measure the vertical displacement of the telescopic arm 53 during the test; the intelligent analysis platform is connected to the pressure sensor 3, the displacement sensor 4 and the hydraulic sensor 56 respectively to receive the oil pressure data of the hydraulic chamber 55, the plate head pressure data and the displacement data during the test in real time, and control the oil pressure in the hydraulic chamber 55 according to the oil pressure data to make the telescopic arm 53 move back and forth along the axis; and the intelligent analysis platform is also wirelessly connected to the rotation drive device of the telescopic arm 53 to control the rotation of the telescopic arm 53 around the axis.

[0032] In this embodiment, the axial direction is the direction of the central axis of the first cylinder 51 and the second cylinder 52, and the radial direction is perpendicular to the axial direction. The hydraulic chamber 55 corresponds to a hydraulic pump. The intelligent analysis platform can control the hydraulic oil pressure in the hydraulic chamber 55 bidirectionally by controlling the output pressure of the hydraulic pump, providing the downward pressure and upward pulling force required for the telescopic arm 53 to move axially. Similarly, the intelligent analysis platform can control the rotational speed and direction of the telescopic arm 53 around the axis by controlling the rotary drive device. The clamp 54 is preferably a ring clamp.

[0033] The use of this device is divided into a preparation stage and a test stage. In the preparation stage, the reaction force component 6 is connected to the self-drilling spinning machine 5 and the self-drilling spinning machine 5 is fixed on the ground. One end of the force transmission rod 2 passes through the first channel 511 and is connected to the pressure sensor 3 and the spiral plate head 1 in sequence. Then, the clamp 54 provides a detachable connection between the telescopic arm 53 and the force transmission rod 2. The movement of the telescopic arm 53 provides power to the force transmission rod 2, the pressure sensor 3, and the spiral plate head 1. The specific downward penetration process of this device is as follows: the clamp 54 clamps the force transmission rod 2, and the telescopic arm 53 rotates while being pressed down by the hydraulic chamber 55, driving the force transmission rod 2, pressure sensor 3, and spiral head 1 to rotate into the soil layer together. When the telescopic arm 53 descends to its maximum limit, the clamp 54 releases the force transmission rod 2, and the telescopic arm 53 rises to its highest position under the upward pulling force provided by the hydraulic chamber. At this time, the clamp 54 re-clamps the other part of the force transmission rod 2, and the telescopic arm 53 drives the force transmission rod 2, pressure sensor 3, and spiral head 1 to rotate downward again. By using the multiple back-and-forth movements of the telescopic arm 53, the force transmission rod 2, pressure sensor 3, and spiral head 1 can be sent into a deeper soil layer, with a penetration depth of over 40 meters. During the load test phase, the intelligent analysis platform controls the oil pressure of the hydraulic chamber 55 in the self-drilling spinneret 5 to perform graded loading or unloading on the force transmission rod 2 based on the real-time data of the hydraulic sensor 56, thereby transferring the load to the spiral plate head 1, and receiving the plate head pressure data and displacement data collected by the pressure sensor 3 and displacement sensor 4, respectively.

[0034] The spiral plate load testing device of this invention achieves automatic penetration of the spiral plate load test through a self-drilling spinning machine, solving the problem that traditional load tests are unable to conduct deep load tests due to factors such as the influence of geological formations and insufficient manual drilling capabilities. This significantly increases the test depth and engineering exploration depth of the spiral plate load test, making it suitable for in-situ testing and exploration of deep soil. The device also improves the force transmission mode of the force transmission rod in traditional load tests through a clamping device, enhancing the overall stability of the structure and greatly reducing the problem of eccentric compression, thus improving the depth and accuracy of the spiral plate load test. Furthermore, through an integrated digital intelligent analysis platform, the spiral plate load test is automated. It can automatically penetrate, continuously test, intelligently load, unload, digitally acquire data, transmit wirelessly over long distances, and perform intelligent analysis according to operating instructions. This solves the problem of traditional spiral plate load tests heavily relying on manual operation, greatly improving the efficiency of the spiral plate load test and reducing testing costs.

[0035] In a preferred embodiment, the force transmission rod 2 includes a single probe 21; or, the force transmission rod includes multiple probes 21, selected according to the depth of the load test and the length of the probes 21.

[0036] Preferably, when the force transmission rod 2 is composed of multiple probes 21, adjacent probes 21 are connected at their top and bottom respectively. In this embodiment, during the downward penetration process of the force transmission rod 2, after one probe 21 has penetrated to a certain depth, the next probe 21 can be connected to continue penetration, gradually increasing the length of the force transmission rod 2 until the spiral plate head 1 is delivered to the designed soil layer position, so that the length of the force transmission rod 2 can be flexibly matched with the test depth of the load test.

[0037] Preferably, the length of the probe rod 21 is 2 to 3 times the length of the telescopic arm 53. In this case, one probe rod 21 needs to be rotated downward by the telescopic arm 53 at least 2 or 3 times before connecting to the next probe rod 21 and continuing to rotate downward.

[0038] In one specific embodiment, the probe length is 1 meter and the telescopic arm length is 0.5 meters.

[0039] Furthermore, such as Figure 4 As shown, a signal transceiver 22 is preferably installed inside the probe rod 21, and a signal sensor 32 is preferably installed on the side of the pressure sensor 3 facing the force transmission rod 2. The signal sensor 32 can convert the pressure signal collected by the pressure sensor 3 into a digital signal, and then transmit it to the intelligent analysis platform through the signal transceiver 22 inside the probe rod 21.

[0040] In this embodiment, the real-time long-distance wireless transmission of digital signals in the soil environment is realized through the signal sensor 32 and the signal transceiver 22 in several probes 21, so that the intelligent analysis platform can receive the load data collected by the pressure sensor 3 in real time during the test, and realize the digital acquisition of deep spiral plate load test.

[0041] More preferably, the pressure sensor 3 is an electromagnetic pressure sensor, the spiral head 1 is an electromagnetic spiral head, and an electromagnetic anchor 31 is provided on the side of the pressure sensor 3 facing the spiral head 1, which can attract the electromagnetic spiral head to the magnetic pressure sensor through electromagnetic action.

[0042] In this embodiment, the switch of the electromagnetic anchor 31 is turned on during the penetration or extraction phase. This uses electromagnetic force to firmly attract the electromagnetic pressure sensor and the electromagnetic spiral head 1 together, preventing the spiral head 1 from detaching during forward or reverse rotation and facilitating its recovery. During the load test, the switch of the electromagnetic anchor 31 is turned off.

[0043] More preferably, the displacement sensor 4 is a pull-wire displacement sensor; a limiter 57 is provided on the side of the clamp 54 away from the force transmission rod 2, and one end of the limiter 57 extends out of the outer wall of the telescopic arm 53; the pull-wire displacement sensor and the limiter 57 can be connected by a vertically extending pull wire 58, so that the pull-wire displacement sensor can measure the vertical displacement of the telescopic arm 53 during the test.

[0044] In this embodiment, the limiter 57 restricts the position of the clamp 54, ensuring its safe and stable operation. During the load test, the spiral plate head 1, pressure sensor 3, force transmission rod 2, and telescopic arm 53 will displace together with the soil deformation. Therefore, the vertical displacement of the telescopic arm 53 is the amount of soil deformation. The drawstring 58 connects the drawstring displacement sensor and the limiter 57 in the vertical direction, allowing the drawstring displacement sensor to directly collect accurate data on soil deformation, thus improving the accuracy of the spiral plate load test. Furthermore, the drawstring displacement sensor can transmit soil deformation data during the test to the intelligent analysis platform in real time, achieving efficient acquisition of soil deformation data and improving the efficiency of the spiral plate load test.

[0045] For example, the draw wire 58 is a high-strength, low-strain draw wire.

[0046] Preferably, several wire-type displacement sensors are provided, which can collect several sets of soil deformation data. In a specific embodiment, two wire-type displacement sensors are provided, symmetrically arranged along the axial direction at the bottom of the second cylinder 52. At each moment, two soil deformation data points symmetrically distributed along the axis can be collected to determine possible random errors in the data.

[0047] Preferably, a plurality of crossbeams 521 are arranged radially at intervals on the outer side wall of the second cylinder 52. The reaction force assembly 6 includes a bidirectional telescopic rod 61 and a balance suspension beam 62. The bidirectional telescopic rod 61 can connect one end of the crossbeam 521 to one end of the balance suspension beam 62. The other end of the balance suspension beam 62 is fixedly installed on the ground by a threaded rod ground anchor 63.

[0048] In this embodiment, the balance suspension beam 62 is connected to the threaded rod ground anchor 63 through a threaded hole. The threaded rod ground anchor 63 can provide test reaction force for the spiral plate load test by being screwed into the ground to a certain depth. The two ends of the bidirectional telescopic rod 61 are preferably connected to the balance suspension beam 62 and the crossbeam 521 of the self-drilling spinning machine respectively through threads. The free extension and retraction of the lever arm of this test device can be realized by adjusting the number of rotations of the threads connected at both ends.

[0049] Preferably, four crossbeams 521 are spaced apart and arranged at 90° angles along the radial direction of the second cylinder. At this time, there are also two sets of four balance beams 62, which are connected to each crossbeam 521 of the self-drilling spinning machine 5 via four bidirectional telescopic rods 61. A variable-speed rotary bearing 64 is preferably provided at the end of the balance beam 62 furthest from the crossbeams 521. The variable-speed rotary bearing 64 can drive the threaded rod anchor 63 to a certain depth in the soil layer, providing test reaction force for the deep spiral plate load test. By simultaneously adjusting the advance of each threaded rod anchor 63 through each variable-speed rotary bearing 64, the self-drilling spinning machine 5 can be aligned and leveled, ensuring the vertical drilling of the subsequent spiral plate head 1 and preventing eccentric pressure on the spiral plate head 1 during the test.

[0050] Preferably, the intelligent analysis platform is wirelessly connected to the variable speed rotary bearing 64 on the balance beam 62 to control the screwing and pulling of the threaded rod ground anchor 63.

[0051] In practical use, a preferred embodiment provides a spiral plate load test method, which includes at least the following steps: (1) Preparation S101: Level the test site and mark the test hole locations according to the test hole locations and surrounding terrain features; S102: Center and level the self-drilling spinning machine, fix the reaction force assembly on the ground, and connect the reaction force assembly to the self-drilling spinning machine; S103: Pass the force transmission rod through the first channel of the self-drilling spinneret and connect it to the electromagnetic anchor and the spiral plate head in sequence. Debug the intelligent analysis platform, calibrate the preloaded spiral plate head, and ensure that the data signal can be transmitted normally. S104: The clamp clamps the force transmission rod, and the intelligent analysis platform controls the telescopic arm to slowly bring the spiral plate head into the soil at the set moving speed and rotation speed. When the telescopic arm moves downward to the maximum limit, the clamp releases the force transmission rod, and the intelligent analysis platform controls the telescopic arm to move upward to the set position. Then, the clamp clamps the force transmission rod again, and the intelligent analysis platform controls the telescopic arm to slowly bring the spiral plate head into the soil at the set moving speed and rotation speed. This cycle continues until the spiral plate head reaches the test soil layer point. (2) Load test S201: Zero the displacement sensor and pressure sensor, start the test, the intelligent analysis platform controls the oil pressure in the hydraulic chamber to perform graded loading, the pressure sensor and displacement sensor provide real-time feedback of the collected plate head pressure data and displacement data, the intelligent analysis platform analyzes the collected plate head pressure data and displacement data and plots the QS curve; S202: After the loading test, the intelligent analysis platform controls the oil pressure in the hydraulic chamber to unload in stages. The pressure sensor and displacement sensor provide real-time feedback of the collected pressure and displacement data of the plate head. The intelligent analysis platform analyzes the collected pressure and displacement data of the plate head, plots the QS curve, and outputs the test report after the unloading test is completed.

[0052] Preferably, in step S103, calibrating the preloaded auger head refers to the intelligent analysis platform controlling the telescopic arm to apply a certain pressure to the auger head to facilitate data signal testing. In step S104, the preferred auger head rotation speed into the soil controlled by the intelligent analysis platform is 10 cm / s.

[0053] During the load test, the pressure applied to the auger head in steps S201 and S202 is provided by the oil pressure in the hydraulic chamber of the self-drilling auger, and transmitted to the force transmission rod through the clamp, and finally gradually transmitted to the auger head through the force transmission rod. During the transmission process, part of the pressure is consumed by the soil friction around the force transmission rod, and the remaining force is transmitted to the auger head and acts on the test soil layer.

[0054] Preferably, before step S201, step S200 is also set: inputting engineering information (soil type, depth, groundwater level, test load, number of loading stages, number of unloading stages, data acquisition time interval, stability and convergence conditions (fast method, slow method), and reloading conditions) into the intelligent analysis platform, and verifying whether the engineering information is accurate.

[0055] In step S201, the graded loading is generally divided into 8 to 10 levels depending on the stratum, with the initial loading being twice the graded load; in step S202, the graded unloading load is generally twice the graded loading load. Preferably, during the load test, when the difference between the pressure data detected by the pressure sensor at the plate head and the set graded load reaches the set supplementary load limit, supplementary loading is performed. The intelligent analysis platform can automatically determine the loading amount, unloading amount, and supplementary load based on the pressure data of the spiral plate head fed back by the pressure sensor, and analyze the soil deformation data to determine whether the stability convergence condition of the load test has been met. If the soil deformation meets the convergence condition, the test can be terminated in advance without performing the remaining loading / unloading stages. For the detailed process of data acquisition in steps S201 and S202, please refer to [link to relevant documentation]. Figure 5 .

[0056] More preferably, when the test requires multiple test points at different depths at the same test hole location, this spiral plate load test method further includes the following process: (3) Continuous load test S301: After completing the previous set of load tests, repeat step S104 and continue to screw the auger head into the next test soil layer point of the test hole. S302: Repeat steps S201~S202; S303: Determine whether the test soil point is the last test soil point of the test borehole. If yes, the continuous load test ends; otherwise, return to step S301.

[0057] Furthermore, after the load test is completed at all test points of the test hole, it is determined whether the electromagnetic spiral plate head needs to be retrieved as needed. If so, the electromagnetic anchor is opened, and the force transmission rod is slowly lifted by rotating the self-drilling spinner in the opposite direction to retrieve the force transmission rod, electromagnetic pressure sensor, and electromagnetic spiral plate head. If the electromagnetic spiral plate head does not need to be retrieved, the electromagnetic anchor is closed, and the force transmission rod is lifted by using the self-drilling spinner.

[0058] In the spiral plate load test method of the present invention, the data processing procedure is as follows: The stress analysis process of the load test is actually a slow change process of loading and soil holding to reach a relatively stable state. As time increases, the deformation of the soil gradually tends to stabilize under each load level. At this point, the load can be continued to the next level or the test can be terminated.

[0059] Apply each load level :

[0060] in, For each level of load pressure ( ); The load on the spiral plate head ( ), The effective area of ​​the spiral plate head ( ).

[0061] During the test, the axial force applied by the hydraulic cylinder of the self-drilling spinning machine to the force transmission rod... :

[0062] in, The axial pressure on the force transmission rod ( ), Lateral frictional resistance of the force transmission rod ( ).

[0063] Frictional resistance of the side wall of the force transmission rod :

[0064] in, The coefficient of friction between the dowel bar and the soil layer. The outer diameter of the force transmission rod ( ), For the test depth ( ).

[0065] Test depth :

[0066] in, The length of the force transmission rod ( ); The remaining length of the force transmission rod on the ground ( ); The length of the electromagnetic pressure sensor ( ).

[0067] applied axial force The load acting on the spiral plate head is :

[0068] in, for t The actual pressure on the spiral plate head at any given moment ( ).

[0069] When each load level With the actual pressure on the spiral plate head The difference reaches the set reload limit. ( When, that is At that time, the self-drilling spinning mill will automatically reload.

[0070] The stability and convergence criteria for each load level: the amount of soil deformation within 2 consecutive hours. When the deformation is less than 0.1 mm, this level of loading test can be terminated, and the soil deformation... and cumulative deformation of soil The formula for calculation is:

[0071]

[0072] in, for t The amount of soil deformation at any given time ( ); The cumulative deformation of displacement sensor #1 ( ); The cumulative deformation of displacement sensor #2 ( ); The cumulative deformation of displacement sensor n# ).

[0073] The spiral plate load testing device of this invention achieves automatic penetration of the spiral plate load test through a self-drilling spinning machine, solving the problem that traditional load tests are unable to conduct deep load tests due to factors such as the influence of geological formations and insufficient manual drilling capabilities. This significantly increases the test depth and engineering exploration depth of the spiral plate load test, making it suitable for in-situ testing and exploration of deep soil. The device also improves the force transmission mode of the force transmission rod in traditional load tests through a clamping device, enhancing the overall stability of the structure and greatly reducing the problem of eccentric compression, thus improving the depth and accuracy of the spiral plate load test. Furthermore, through an integrated digital intelligent analysis platform, the spiral plate load test is automated. It can automatically penetrate, continuously test, intelligently load, unload, digitally acquire data, transmit wirelessly over long distances, and perform intelligent analysis according to operating instructions. This solves the problem of traditional spiral plate load tests heavily relying on manual operation, greatly improving the efficiency of the spiral plate load test and reducing testing costs.

[0074] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A spiral plate load testing device, characterized in that, This includes a spiral plate head, force transmission rod, pressure sensor, displacement sensor, self-drilling spinning mill, reaction force assembly, and intelligent analysis platform; among which: The self-drilling spinning press includes a first cylinder and a second cylinder arranged coaxially; wherein: the first cylinder has a first channel for accommodating a force transmission rod, a second channel is formed between the first cylinder and the second cylinder, a telescopic arm that can move axially and rotate around the axis is provided in the second channel, a clamp is provided at the bottom of the telescopic arm, the clamp can clamp or release the force transmission rod, and the top surface of the telescopic arm and the second channel form a hydraulic cavity, and a hydraulic sensor is correspondingly provided in the hydraulic cavity; The reaction force assembly is fixedly installed on the ground and used to secure the self-drilling spinning machine during the test; A pressure sensor is installed between the force transmission rod and the auger head to measure the pressure on the auger head during the test; a displacement sensor is installed at the bottom of the second cylinder to measure the vertical displacement of the telescopic arm during the test. The intelligent analysis platform is connected to the hydraulic sensor, pressure sensor and displacement sensor respectively, to receive the oil pressure data of the hydraulic chamber, the pressure data of the plate head during the test and the displacement data in real time, and to control the oil pressure in the hydraulic chamber according to the oil pressure data to make the telescopic arm move back and forth along the axis; the intelligent analysis platform is also wirelessly connected to the rotation drive device of the telescopic arm to control the rotation of the telescopic arm around the axis. During the test, the clamp clamps the force transmission rod, and the intelligent analysis platform controls the telescopic arm to slowly bring the spiral plate head into the soil at the set moving and rotating speeds. When the telescopic arm moves downward to its maximum limit, the clamp releases the force transmission rod, and the intelligent analysis platform controls the telescopic arm to move upward to the set position. The clamp clamps the force transmission rod again, and the intelligent analysis platform further controls the telescopic arm to slowly bring the spiral plate head into the soil at the set moving and rotating speeds. This cycle continues until the spiral plate head reaches the test soil layer.

2. The spiral plate load testing device according to claim 1, characterized in that, The displacement sensor is a pull-wire type displacement sensor; a limiter is provided on the side of the clamp away from the force transmission rod, and one end of the limiter extends out of the outer wall of the telescopic arm; The pull-wire displacement sensor is connected to the limiter via a vertically extending pull wire, and the pull-wire displacement sensor is used to measure the vertical displacement of the telescopic arm during the test.

3. The spiral plate load testing device according to claim 1, characterized in that, The pressure sensor is an electromagnetic pressure sensor, the spiral plate head is an electromagnetic spiral plate head, and an electromagnetic anchor is provided on the side of the pressure sensor facing the spiral plate head. The electromagnetic spiral plate head is attracted to the electromagnetic pressure sensor by electromagnetic action.

4. The spiral plate load testing device according to claim 1, characterized in that, The force transmission rod includes a single probe, or the force transmission rod includes multiple probes, with adjacent probes connected at their top and bottom respectively.

5. The spiral plate load testing device according to claim 4, characterized in that, A signal transceiver is installed inside the probe rod; a signal sensor is installed on the side of the pressure sensor facing the force transmission rod, which is used to convert the pressure signal collected by the pressure sensor into a digital signal, and then transmit it to the intelligent analysis platform through the signal transceiver inside the probe rod.

6. The spiral plate load testing device according to claim 4, characterized in that, The length of the probe rod is 2 to 3 times the length of the telescopic arm.

7. The spiral plate load testing device according to claim 1, characterized in that, Multiple crossbeams are arranged radially at intervals on the outer side wall of the second cylinder; The reaction force assembly includes a bidirectional telescopic rod and a balance suspension beam; one end of the balance suspension beam is connected to the crossbeam through the bidirectional telescopic rod, and the other end of the balance suspension beam is fixedly installed on the ground through a threaded rod ground anchor.

8. The spiral plate load testing device according to claim 7, characterized in that, The crossbeams are spaced four times apart and are arranged at 90° along the radial direction of the second cylinder. and / or A variable speed rotary bearing is provided at the end of the balance beam away from the crossbeam, and the variable speed rotary bearing is used to drive the threaded rod ground anchor to rotate.

9. A method for testing the load on a spiral plate, characterized in that, This method utilizes the spiral plate load testing apparatus described in any one of claims 1 to 8, and includes the following steps: (1) Preparation S101: Level the test site and mark the test hole locations according to the test hole locations and surrounding terrain features; S102: Center and level the self-drilling spinning machine, fix the reaction force assembly on the ground, and connect the reaction force assembly to the self-drilling spinning machine; S103: Pass the force transmission rod through the first channel of the self-drilling spinneret and connect it in sequence to the pressure sensor and the spiral plate head. Debug the intelligent analysis platform, calibrate the preloaded spiral plate head, and ensure that the data signal can be transmitted normally. S104: The clamp clamps the force transmission rod, and the intelligent analysis platform controls the telescopic arm to slowly bring the spiral plate head into the soil at the set moving speed and rotation speed. When the telescopic arm moves downward to the maximum limit, the clamp releases the force transmission rod, and the intelligent analysis platform controls the telescopic arm to move upward to the set position. The clamp clamps the force transmission rod again, and the intelligent analysis platform further controls the telescopic arm to slowly bring the spiral plate head into the soil at the set moving speed and rotation speed. This cycle continues until the spiral plate head reaches the test soil layer point. (2) Load test S201: Zero the displacement sensor and pressure sensor, start the test, the intelligent analysis platform controls the oil pressure in the hydraulic chamber to perform graded loading, the pressure sensor and displacement sensor provide real-time feedback of the collected plate head pressure data and displacement data, the intelligent analysis platform analyzes the collected plate head pressure data and displacement data and plots the QS curve; S202: After the loading test, the intelligent analysis platform controls the oil pressure in the hydraulic chamber to unload in stages. The pressure sensor and displacement sensor provide real-time feedback of the collected pressure and displacement data of the plate head. The intelligent analysis platform analyzes the collected pressure and displacement data of the plate head, plots the QS curve, and outputs the test report after the unloading test is completed.

10. A method for testing the load on a spiral plate according to claim 9, characterized in that, It also includes the following processes: (3) Continuous load test S301: After completing the previous set of load tests, repeat step S104 and continue to screw the auger head into the next test soil layer point of the test hole. S302: Repeat steps S201~S202; S303: Determine whether the test soil point is the last test soil point of the test borehole. If yes, the continuous load test ends; otherwise, return to step S301.

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