An in-situ drilling test device and method for testing the strength of surrounding rock in blast holes based on the rebound method

Abstract

This invention discloses an in-situ drilling test device and method for testing the strength of surrounding rock in blast holes based on the rebound method. The device consists of metal blades, a connecting mechanism, a rebound sensor, a blade sleeve, a ground ring, a ground support, a telescopic rod, and a ground control and data processor. The metal blades and blade sleeve are connected by the connecting mechanism, and the ground ring and blade sleeve are connected by the telescopic rod. During operation, the blade sleeve descends uniformly within the borehole under the influence of the telescopic rod, while the metal blades cyclically impact and rebound against the borehole wall. The ground control and data processor stores and records the rebound value for each impact. Using the parameters measured by this device, a mathematical model can be established between the rebound value and the strength of the surrounding rock in the blast hole, thereby obtaining the surrounding rock strength parameters and evaluating the blastability of the surrounding rock. This invention has advantages such as simple structure, easy operation, low testing cost, accurate evaluation results, and strong representativeness.

Description

Technical Field

[0001] This invention relates to the field of rock mechanics and engineering technology, specifically to an in-situ drilling test device and method for testing the strength of surrounding rock in blast holes based on the rebound method. Background Technology

[0002] The development of engineering blasting technology in my country is inseparable from the needs of national economic construction. Engineering blasting technology has become one of the essential supporting technologies for my country's economic and social development, especially in mining engineering and tunnel engineering. In the field of mining engineering, with the increasing awareness of ecological and environmental protection in recent years, research and exploration into refined blasting, improving blasting efficiency, and reducing explosive consumption have been gradually deepening. Unlike traditional blasting control technologies, refined blasting technology has lower explosive consumption, higher safety, and less environmental impact, and will become the future trend of mine blasting technology. To achieve refined blasting, the coordinated work of multiple systems is required. The mechanical properties of rock mass are closely related to its drillability and blastability, serving as the basis for the rational design of blasting parameters and a key indicator for evaluating the ease of subsequent mechanical crushing of such rock masses. To improve blasting efficiency, reduce blasting costs, and achieve refined blasting, it is necessary to accurately classify and evaluate the blastability of ore and rock. In existing technologies, the strength parameters of the rock mass are mainly used as the primary indicator for evaluating and classifying its blastability. There are two main methods for determining the strength parameters of rock masses. One method involves sampling the rock and ore, processing it into standard specimens in the laboratory, and then measuring the strength parameters of these standard specimens through indoor testing. These parameters are then considered to represent the mechanical parameters of the rock mass in the field. The biggest drawback of this method is that the properties of rock vary at different locations in the field, and the number of sampling points is limited, resulting in poor representativeness and failing to meet the requirements of precise blasting. To overcome the shortcomings of laboratory testing, in-situ testing methods for rock mass strength parameters have been developed. However, in existing in-situ testing techniques, the method for determining the strength of the surrounding rock in blast holes mainly involves monitoring parameters such as thrust, torque, feed rate, and rotational speed on the drill bit or cutterhead to determine the compressive strength of the rock. This type of technology requires modification of the drill bit or the use of special drill bits, which is costly, complex, and the monitoring instruments are easily damaged when acquiring parameters such as torque and thrust.

[0003] The rebound method is a rapid and simple measurement method that uses the rebound value as an index related to rock mass strength to estimate rock mass strength. To address the problems of the existing technology, this invention provides an in-situ testing device and method for measuring the strength of surrounding rock in blast holes based on the rebound method. The rebound value measured by this device can be further converted and calculated to obtain the rock mass strength index. Then, using a mathematical model for evaluating the blastability of rock mass, the blastability of the rock mass can be evaluated and classified, thus providing important theoretical basis and guidance for achieving refined blasting. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides an in-situ drilling test device and method for testing the strength of the surrounding rock of a blast hole based on the rebound method. The device aims to achieve in-situ testing of the strength of the surrounding rock of a blast hole through the cyclic rebound of metal blades. The technical process is simple and low-cost. Furthermore, it can establish a relationship model between the strength of the surrounding rock of a blast hole and the parameters for evaluating the blastability of the rock mass, so as to facilitate the assessment and classification of the blastability of the in-situ rock mass.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A borehole surrounding rock strength testing device based on the rebound method is characterized by comprising a metal blade, a connecting mechanism, a rebound sensor, a blade sleeve, a ground ring, a ground support, a telescopic rod, and a ground control and data processor. The metal blade is an arc-shaped metal sheet with a certain strength, and the metal blade and the blade sleeve are connected by the connecting mechanism. The connecting mechanism consists of a metal protective shell and its internal components: a horizontal rack, a horizontal gear, a horizontal gear power mechanism, a vertical rack, a vertical gear, a vertical gear power mechanism, and a spring. The movement direction of the horizontal rack is parallel to the movement direction of the metal blade; the movement direction of the vertical gear on the vertical rack is perpendicular to the movement direction of the metal blade. The rebound sensor is mounted on the spring. Ground supports are evenly installed on the ground ring, and the ends of the ground ring and the blade sleeve are connected by telescopic rods. The telescopic rods can extend and retract at a set speed under the drive of a motor. The ground control and data processor controls the operation of the telescopic rods and the connecting mechanism, collects and stores data measured by the rebound sensor, and performs analysis and processing. The ground control and data processor is connected to the connecting mechanism via power and signal cables.

[0007] Further, the feature is that the metal protective shell is a hollow, elongated box-shaped body, with one end welded to the blade sleeve and a rectangular through hole at the bottom of the other end; the horizontal rack passes through the rectangular through hole of the metal protective shell, with one end welded and fixed to the inner side of the metal blade and the other end fixedly connected to a spring, the other end of which is fixed to the inner end of the metal protective shell; a horizontal gear is mounted on the horizontal rack, and the horizontal gear is connected to a horizontal gear power mechanism, which contains a motor; the horizontal gear is driven by the horizontal gear power mechanism to drive the horizontal gear... The mechanism consists of a vertical rack arranged perpendicular to the horizontal rack, with one end welded to the inner wall of a metal protective housing. A vertical gear is mounted on the vertical rack, connected to a vertical gear power mechanism. A motor is installed in the vertical gear power mechanism, which is rigidly connected to the horizontal gear power mechanism to form an L-shaped connecting rod. The vertical gear is driven by the vertical gear power mechanism to roll on the vertical rack, thereby driving the vertical gear power mechanism, the horizontal gear power mechanism, and the horizontal gear to move in a direction perpendicular to the horizontal rack, achieving disengagement and re-engagement of the horizontal gear and the horizontal rack.

[0008] Furthermore, the feature is that the horizontal gear power mechanism is disposed close to the side panel with a rectangular through hole at the bottom of the metal protective housing, with a small gap between them to allow the horizontal gear and the horizontal rack to disengage and re-engage.

[0009] Furthermore, the feature is that the metal blades are three arc-shaped metal sheets with an arc of 120°; the number of the connecting mechanisms matches the number of the metal blades, and they are also arranged at 120° to each other.

[0010] Furthermore, the feature is that by setting the operating parameters of the motor, the initial potential energy of the three springs after compression is the same, and they can be released simultaneously according to a preset time interval, so that the springs drive the three blades to hit the rock wall at the same time, and the rebound sensor records the magnitude of the rebound value.

[0011] Furthermore, the rebound sensor records and stores the maximum deformation value of the spring at the moment the metal blade hits the rock wall and the minimum deformation value at the moment the spring rebounds to its maximum extent during each impact of the metal blade, calculates the average value of the difference between the maximum deformation value and the minimum deformation value of each spring, and sets it as the rebound value for each impact.

[0012] Furthermore, the ground support is characterized in that it is an adjustable rigid support used to support the testing device and ensure that the ground ring is level when the device is set up.

[0013] Furthermore, the telescopic rod is characterized in that it is a high-strength, lightweight metal rod, and its maximum extension length is greater than the measured drilling depth. Preferably, the number of telescopic rods is four.

[0014] Furthermore, the outer diameter of the ground ring is 10-15 cm larger than the borehole diameter, and when the spring is in its natural state, the outer diameter of the ring formed by the blade sleeve, the connecting mechanism, and the metal blade is 3-5 cm smaller than the borehole diameter.

[0015] The method of using the above-mentioned in-situ drilling test device for the strength of surrounding rock in blast holes based on the rebound method is characterized by the following steps:

[0016] Step 1: Drill holes in the blasting area according to the designed hole network parameters as blast holes for explosive blasting. Select 5-10 holes as basic holes, set up a support on the ground, and install the sleeve and blade rebound mechanism. Align the metal blade and blade sleeve with the opening of the basic drill hole.

[0017] Step 2: Set the working parameters of the horizontal gear power mechanism, vertical gear power mechanism and telescopic rod drive motor on the ground control and data processor, thereby setting the frequency of the metal blade impacting the borehole rock wall, and at the same time ensuring that the spring has a suitable initial potential energy, so as to ensure that the metal blade impacts the borehole rock wall with appropriate kinetic energy, while avoiding excessive initial potential energy that would reduce the life of the metal blade.

[0018] Step 3: Activate the telescopic rod control switch. The telescopic rod extends downwards, and the metal blade and blade sleeve descend at a constant speed along the borehole. At the same time, activate the power supply of the horizontal gear power mechanism and the vertical gear power mechanism motors to start the cyclic impact and rebound operation of the metal blade against the borehole wall. The rebound value of each impact is stored and recorded on the ground control and data processor.

[0019] Step 4: When the metal blade and blade sleeve descend to the bottom of the borehole, turn off the power to the drive motors of the horizontal gear power mechanism and the vertical gear power mechanism, and adjust the drive motor of the telescopic rod to reverse it. The telescopic rod will begin to retract upward until the metal blade and blade sleeve are pulled out of the borehole.

[0020] Step 5: Remove the test device for future use.

[0021] Beneficial effects

[0022] Compared with the prior art, the present invention has the following advantages: the testing principle and structure are simple, making it easy for on-site operators to master and operate; the testing process is simple and quick, and the testing cost is low; at the same time, it can realize in-situ testing of relevant mechanical parameters of rock mass below the surface, and the test results are accurate and highly representative, which can provide strong technical support for the refined blasting of rock mass.

[0023] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0024] Figure 1 A three-dimensional schematic diagram of the appearance of an in-situ drilling test device for the strength of surrounding rock in a blast hole based on the rebound method, provided for an embodiment of the present invention;

[0025] Figure 2 A three-dimensional schematic diagram of the connection mechanism of an in-situ drilling test device for the strength of surrounding rock in a blast hole based on the rebound method, provided for an embodiment of the present invention;

[0026] Figure 3 A schematic diagram of an in-situ drilling test device for the strength of surrounding rock in a blast hole based on the rebound method, provided in an embodiment of the present invention;

[0027] Numbering in the diagram: 1-Ground support, 2-Telescopic rod, 3-Metal blade, 4-Connecting mechanism, 5-Vertical gear, 6-Metal protective housing, 7-Vertical rack, 8-Spring, 9-Horizontal gear, 10-Horizontal rack, 11-Ground ring, 12-Horizontal gear power mechanism, 13-Vertical gear power mechanism, 14-Ground control and data processor, 15-Power and signal cable, 16-Blade sleeve, 17-Drill hole. Detailed Implementation

[0028] The technical solutions of various embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1

[0030] like Figures 1-3As shown in the figure, an in-situ drilling test device for the strength of surrounding rock in blast holes based on the rebound method is provided in this embodiment of the invention. It includes a metal blade 3, a connecting mechanism 4, a rebound sensor, a blade sleeve 16, a ground ring 11, a ground support 1, a telescopic rod 2, and a ground control and data processor 14. The metal blade 3 is an arc-shaped metal sheet with a certain strength. The metal blade 3 and the blade sleeve 16 are connected by the connecting mechanism 4. The connecting mechanism 4 consists of a metal protective shell 6 and its internal components: a horizontal rack 10, a horizontal gear 9, a horizontal gear power mechanism 12, a vertical rack 7, a vertical gear 5, a vertical gear power mechanism 13, and a spring 8. The horizontal rack... The direction of motion is parallel to the direction of motion of the metal blade 3; the direction of motion of the vertical gear 5 on the vertical rack 7 is perpendicular to the direction of motion of the metal blade 3; the rebound sensor is set on the spring 8; ground supports 1 are evenly installed on the ground ring 11, and the ends of the ground ring 11 and the blade sleeve 16 are connected by telescopic rods 2. The telescopic rods 2 can extend and retract at a set speed under the drive of the motor; the ground control and data processor 14 controls the operation of the telescopic rods 2 and the connecting mechanism 4, collects and stores the data measured by the rebound sensor and performs analysis and processing, and the ground control and data processor 14 and the connecting mechanism 4 are connected by power and signal cables 15.

[0031] Furthermore, the metal protective shell 6 is a hollow, elongated box. One end of the metal protective shell 6 is welded to the blade sleeve 16, and the bottom of the other end is provided with a rectangular through hole. The horizontal rack 10 passes through the rectangular through hole of the metal protective shell, one end of which is welded and fixed to the inner side of the metal blade 3, and the other end is fixedly connected to the spring 8. The other end of the spring 8 is fixed to the inner end of the metal protective shell 6. A horizontal gear 9 is mounted on the horizontal rack 10. The horizontal gear 9 is connected to the horizontal gear power mechanism 12. A motor is installed in the horizontal gear power mechanism 12. The horizontal gear 9 can drive the horizontal rack 10 to move through the horizontal gear power mechanism 12. Vertical The rack 7 is arranged perpendicular to the horizontal rack 10, and one end of it is welded to the inner side wall of the metal protective shell 6. A vertical gear 5 is installed on the vertical rack 7. The vertical gear 5 is connected to the vertical gear power mechanism 13. A motor is installed in the vertical gear power mechanism 13. The vertical gear power mechanism 13 is rigidly connected to the horizontal gear power mechanism 12 to form an L-shaped connecting rod. The vertical gear 5 can roll on the vertical rack 7 through the vertical gear power mechanism 13, thereby driving the vertical gear power mechanism 13, the horizontal gear power mechanism 12 and the horizontal gear 9 to move in a direction perpendicular to the horizontal rack 10, realizing the disengagement and re-engagement of the horizontal gear 9 with the horizontal rack 10.

[0032] Furthermore, the horizontal gear power mechanism 12 is positioned close to the side panel with a rectangular through hole at the bottom of the metal protective housing 6, with a small gap between them to allow the horizontal gear 9 to disengage and re-engage with the horizontal rack 10. Through the limiting effect of the panel, it can prevent the horizontal gear 9 from driving the vertical gear 5 to move and disengage from the vertical rack 7 during rotation.

[0033] Furthermore, the metal blades 3 are three arc-shaped metal pieces with an arc of 120°; the number of connecting mechanisms 4 matches the number of metal blades 3, and they are also arranged at 120° to each other.

[0034] Furthermore, by setting the operating parameters of the motor, the initial potential energy of the three springs 8 after compression is the same, and they can be released simultaneously according to a preset time interval, so that the springs drive the three blades to hit the rock wall at the same time, and the rebound sensor records the magnitude of the rebound value.

[0035] Furthermore, the rebound sensor records and stores the maximum deformation value of the spring 8 at the moment the metal blade 3 impacts the rock wall during each impact process and the minimum deformation value at the moment the spring 8 rebounds to its maximum extent. It calculates the average value of the difference between the maximum deformation value and the minimum deformation value of each spring and sets it as the rebound value for each impact.

[0036] Furthermore, the ground support 1 is an adjustable rigid support used to support the testing device and ensure that the ground ring 11 is horizontal when the device is set up.

[0037] Furthermore, the telescopic rod 2 is a high-strength, lightweight metal rod, and its maximum extension length is greater than the measured drilling depth. Preferably, the number of telescopic rods is four.

[0038] Furthermore, the outer diameter of the ground ring 11 is 10-15 cm larger than the borehole diameter. When the spring 8 is in its natural state, the outer diameter of the ring formed by the blade sleeve 16, the connecting mechanism 4, and the metal blade 3 is 3-5 cm smaller than the borehole diameter.

[0039] The working principle of the metal blade impact and rebound of the test device in this embodiment is as follows: When the test device is working, the connecting mechanism controls the metal blade 3 to cyclically impact the rock mass of the borehole wall. Each time it impacts, the motor in the horizontal gear power mechanism 12 first drives the horizontal gear 9, which causes the horizontal rack 10 to move and compress the spring 8 to the set position. At this time, the motor of the horizontal gear power mechanism 12 is turned off and the motor of the vertical gear power mechanism 13 is started, which drives the vertical gear 5 to drive the horizontal gear 9 to move in a direction perpendicular to the horizontal rack 10 until the horizontal gear 9 completely disengages from the horizontal rack 10. At this time, the horizontal rack 10 loses its constraint and will pop out under the action of the spring 8, causing the metal blade 3 at its end to impact the borehole wall. After the impact is completed, the motor of the vertical gear power mechanism 13 reverses, so that the horizontal gear 9 and the horizontal rack 10 re-engage and start the next impact.

[0040] Example 2

[0041] This embodiment provides a method for using an in-situ drilling test device for the strength of surrounding rock in a borehole based on the rebound method, as described in Embodiment 1, including the following steps:

[0042] Step 1: Drill borehole 17 in the blasting area according to the designed borehole network parameters as the blasting holes for the explosive charge. Select 5-10 boreholes as the basic boreholes 17. Set up a support on the ground and install the sleeve and blade rebound mechanism. Align the metal blade and blade sleeve with the opening of the basic borehole.

[0043] Step 2: Set the working parameters of the horizontal gear power mechanism 12, the vertical gear power mechanism 13 and the telescopic rod drive motor on the ground control and data processor 14, thereby setting the frequency of the metal blade 3 hitting the borehole rock wall, and at the same time ensuring that the spring 8 has a suitable initial potential energy, so as to ensure that the metal blade 3 hits the borehole rock wall with a suitable kinetic energy, while avoiding excessive initial potential energy that would reduce the life of the metal blade.

[0044] Step 3: Activate the telescopic rod control switch. The telescopic rod 2 extends downward, and the metal blade 3 and blade sleeve 16 descend at a constant speed along the borehole. At the same time, activate the power supply of the motors of the horizontal gear power mechanism 12 and the vertical gear power mechanism 13 to start the cyclic impact and rebound operation of the metal blade 3 on the borehole wall. The rebound value of each impact is stored and recorded on the ground control and data processor 14.

[0045] Step 4: When the metal blade 3 and blade sleeve 16 descend to the bottom of the borehole, turn off the power to the drive motors of the horizontal gear power mechanism 12 and the vertical gear power mechanism 13, and adjust the drive motor of the telescopic rod 2 to reverse it. The telescopic rod 2 will begin to retract upward until the metal blade 3 and blade sleeve 16 are pulled out of the borehole.

[0046] Step 5: Remove the test device for future use.

[0047] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An in-situ drilling test device for the strength of surrounding rock in blast holes based on the rebound method, characterized in that, The system includes metal blades, a connecting mechanism, a rebound sensor, a blade sleeve, a ground ring, ground supports, telescopic rods, and a ground control and data processor. The metal blades are arc-shaped metal sheets with a certain strength, and are connected to the blade sleeve via the connecting mechanism. The connecting mechanism consists of a metal protective shell and its internal components: a horizontal rack, a horizontal gear, a horizontal gear power mechanism, a vertical rack, a vertical gear, a vertical gear power mechanism, and a spring. The horizontal rack moves parallel to the metal blade; the vertical gear moves perpendicular to the metal blade. The rebound sensor is mounted on the spring. Ground supports are evenly installed on the ground ring, and the ground ring is connected to the blade sleeve via telescopic rods. These telescopic rods extend and retract at a set speed driven by a motor. The ground control and data processor controls the operation of the telescopic rods and the connecting mechanism, collects and stores data measured by the rebound sensor, and performs analysis and processing. The ground control and data processor is connected to the connecting mechanism via power and signal cables. The metal protective shell is a hollow, elongated box. One end of the metal protective shell is welded to the blade sleeve, and the bottom of the other end has a rectangular through hole. The horizontal rack passes through the rectangular through hole of the metal protective shell. One end of the rack is welded and fixed to the inner side of the metal blade, and the other end is fixedly connected to a spring. The other end of the spring is fixed to the inner end of the metal protective shell. A horizontal gear is mounted on the horizontal rack, and the horizontal gear is connected to a horizontal gear power mechanism. A motor is installed in the horizontal gear power mechanism, and the horizontal gear can drive the horizontal rack to move through the horizontal gear power mechanism. The vertical rack is arranged perpendicular to the horizontal rack. One end of the rack is welded to the inner side wall of the metal protective shell, and a vertical gear is mounted on the vertical rack. The vertical gear is connected to a vertical gear power mechanism, and a motor is installed in the vertical gear power mechanism. The vertical gear power mechanism and the horizontal gear power mechanism are rigidly connected to form an L-shaped connecting rod. The vertical gear can roll on the vertical rack through the vertical gear power mechanism, thereby driving the vertical gear power mechanism, the horizontal gear power mechanism, and the horizontal gear to move in a direction perpendicular to the horizontal rack, realizing the disengagement and re-engagement of the horizontal gear and the horizontal rack. The metal blades are three arc-shaped metal pieces with an arc of 120°; the number of the connecting mechanisms matches the number of metal blades, and they are also arranged at 120° to each other. By setting the operating parameters of the motor, the initial potential energy of the three springs after compression is the same, and they can be released simultaneously at preset time intervals, so that the springs drive the three blades to hit the rock wall at the same time, and the rebound value is recorded by the rebound sensor.

2. The in-situ drilling test device for the strength of surrounding rock in blast holes based on the rebound method according to claim 1, characterized in that, The horizontal gear power mechanism is positioned close to the side panel with a rectangular through hole at the bottom of the metal protective housing, with a small gap between them to allow the horizontal gear to disengage and re-engage with the horizontal rack.

3. The in-situ drilling test device for the strength of surrounding rock in blast holes based on the rebound method according to claim 1, characterized in that, The rebound sensor records and stores the maximum deformation value of the spring at the moment the metal blade hits the rock wall and the minimum deformation value at the moment the spring rebounds to its maximum extent during each impact. It calculates the average value of the difference between the maximum and minimum deformation values ​​of each spring and sets it as the rebound value for each impact.

4. The in-situ drilling test device for the strength of surrounding rock in blast holes based on the rebound method according to claim 1, characterized in that, The ground support is an adjustable rigid support used to support the testing device and ensure that the ground ring is level when the device is set up.

5. The in-situ drilling test device for the strength of surrounding rock in blast holes based on the rebound method according to claim 1, characterized in that, The telescopic rod is a high-strength, lightweight metal rod, and its maximum extension length is greater than the measured drilling depth. Preferably, the number of the telescopic rods is four.

6. The in-situ drilling test device for the strength of surrounding rock in blast holes based on the rebound method according to claim 1, characterized in that, The outer diameter of the ground ring is 10-15cm larger than the borehole diameter. When the spring is in its natural state, the outer diameter of the ring formed by the blade sleeve, the connecting mechanism, and the metal blade is 3-5cm smaller than the borehole diameter.

7. The method of using the in-situ drilling test device for the strength of surrounding rock in blast holes based on the rebound method according to any one of claims 1-6, characterized in that, Includes the following steps: Step 1: Drill holes in the blasting area according to the designed hole network parameters as blast holes for explosive blasting. Select 5-10 holes as basic holes, set up a support on the ground, and install the sleeve and blade rebound mechanism. Align the metal blade and blade sleeve with the opening of the basic drill hole. Step 2: Set the working parameters of the horizontal gear power mechanism, vertical gear power mechanism and telescopic rod drive motor on the ground control and data processor, thereby setting the frequency of the metal blade impacting the borehole rock wall, and at the same time ensuring that the spring has a suitable initial potential energy, so as to ensure that the metal blade impacts the borehole rock wall with appropriate kinetic energy, while avoiding excessive initial potential energy that would reduce the life of the metal blade. Step 3: Activate the telescopic rod control switch. The telescopic rod extends downwards, and the metal blade and blade sleeve descend at a constant speed along the borehole. At the same time, activate the power supply of the horizontal gear power mechanism and the vertical gear power mechanism motors to start the cyclic impact and rebound operation of the metal blade against the borehole wall. The rebound value of each impact is stored and recorded on the ground control and data processor. Step 4: When the metal blade and blade sleeve descend to the bottom of the borehole, turn off the power to the drive motors of the horizontal gear power mechanism and the vertical gear power mechanism, and adjust the drive motor of the telescopic rod to reverse it. The telescopic rod will begin to retract upward until the metal blade and blade sleeve are pulled out of the borehole. Step 5: Remove the test device for future use.

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