A rapid testing device for rock deformation parameters

Abstract

This utility model discloses a rapid testing device for rock deformation parameters, comprising a protective shell, one end of which is connected to the drill pipe and the other end to the drill bit. A power supply module, a resistance strain gauge group, a deformation parameter testing module, and a wireless transmission module are installed inside the protective shell. The power supply module provides power to the resistance strain gauge group, the deformation parameter testing module, and the wireless transmission module. The internal power supply line connecting the power supply module and the resistance strain gauge group is connected to the deformation parameter testing module via a signal transmission line. The deformation parameter testing module is electrically connected to the wireless transmission module. This utility model, by deploying resistance strain gauges, the deformation parameter testing module, and the wireless transmission module, monitors the strain signal generated by the interaction between the drilling equipment and the rock in real time, achieving rapid, accurate, and real-time testing of the Poisson's ratio of the rock mass during drilling, thereby guiding the evaluation of surrounding rock stability and the optimization design of support schemes in underground engineering.

Description

Technical Field

[0001] This utility model belongs to the field of rock mechanics testing technology, specifically relating to a rapid testing device for rock deformation parameters. Background Technology

[0002] The statements herein provide only background information related to this invention and do not necessarily constitute prior art.

[0003] In the design and construction of underground engineering projects, rock deformation parameters (such as Poisson's ratio and elastic modulus) are key indicators characterizing the mechanical behavior of rock masses. Testing these parameters allows us to understand the deformation patterns of rocks under stress, providing a scientific basis for engineering design and construction. Specifically, the deformation characteristics of rocks directly affect the selection and design of support structures. Accurate deformation parameters help optimize support schemes, improving engineering safety and economy. Rock deformation parameters can be used to analyze the stress distribution and deformation trends of the surrounding rock, predict potential geological hazards (such as collapses and rock bursts), and thus take preventative measures in advance to ensure construction safety. During drilling, real-time acquisition of rock deformation parameters (such as Poisson's ratio) can help adjust drilling parameters (such as drill pressure and rotation speed), improving drilling efficiency, reducing equipment wear, and avoiding construction risks caused by unclear rock mass characteristics.

[0004] Poisson's ratio is a core parameter for evaluating the mechanical properties of rock masses, optimizing support design, and predicting the stability of surrounding rock. Currently, commonly used testing methods for rock deformation parameters include laboratory tests and in-situ tests. Laboratory tests require obtaining complete rock cores through drilling into the surrounding rock, which are then processed into standard rock samples for testing. This method is time-consuming and costly, and it is difficult to obtain core samples for fractured surrounding rock. In-situ testing methods include acoustic testing and borehole modulus analysis, which can directly measure in-situ rock mass deformation parameters. However, these methods are time-consuming, require drilling into the surrounding rock, and cannot achieve real-time monitoring of deformation parameters. Utility Model Content

[0005] The purpose of this invention is to provide a rapid testing device for rock deformation parameters, which can realize rapid, in-situ and real-time testing of Poisson's ratio of rocks, and also overcome the problem of data transmission, thereby improving the testing efficiency and accuracy of rock mechanical parameters.

[0006] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0007] In a first aspect, embodiments of this utility model provide a rapid testing device for rock deformation parameters, comprising a protective housing, one end of which is connected to a drill pipe and the other end to a drill bit; a power supply module, a resistance strain gauge group, a deformation parameter testing module, and a wireless transmission module are installed inside the protective housing; the power supply module is connected to the resistance strain gauge group, the deformation parameter testing module, and the wireless transmission module respectively through an internal power supply line; the internal power supply line connecting the power supply module and the resistance strain gauge group is connected to the deformation parameter testing module through a signal transmission line; and the deformation parameter testing module is electrically connected to the wireless transmission module.

[0008] As a further technical solution, the resistance strain gauge group is fixed on the inner wall surface of the protective housing. The resistance strain gauge group includes a transverse strain gauge and a longitudinal strain gauge, which are arranged vertically.

[0009] As a further technical solution, the transverse strain gauge is perpendicular to the drilling axis direction, and the longitudinal strain gauge is parallel to the drilling axis direction.

[0010] As a further technical solution, the resistance strain gauge group is provided in two sets, and the two sets of resistance strain gauges are equally spaced in the circumferential direction of the protective shell.

[0011] As a further technical solution, the internal power supply line connecting the resistance strain gauge group to the power supply module includes a first voltage divider branch and a second voltage divider branch arranged in parallel. The midpoint voltage of the first voltage divider branch and the second voltage divider branch is connected to the deformation parameter testing module through a data transmission line.

[0012] As a further technical solution, a working fixed resistor is provided on the first voltage divider branch, and the working fixed resistor is connected in series with the strain gauge group and then connected to the power supply module. Two branch fixed resistors are provided on the second voltage divider branch, and the two branch fixed resistors are connected in series and then connected to the power supply module.

[0013] As a further technical solution, the resistance values ​​of both the working fixed resistor and the branch fixed resistor are equal to the resistance of the resistance strain gauge group.

[0014] As a further technical solution, the protective shell is a circular tube, one end of which is connected to the drill bit by a thread, and the other end is connected to the drill rod by a thread; a hollow water passage hole is provided at the center of the protective shell, and the two ends of the hollow water passage hole are respectively connected to the water passage holes on the drill rod and the drill bit.

[0015] As a further technical solution, the power supply module is a toroidal lithium cobalt oxide battery. The power supply module adopts a fully sealed structure and is provided with a metal charging contact interface, which is embedded in the surface of the protective shell.

[0016] As a further technical solution, a detachable protective cover is provided at the metal charging contact interface. The protective cover is fixed to the surface of the protective shell by screwing or magnetic attraction. A sealing ring is embedded on the inner side of the protective cover, and the outer surface of the protective cover is flush with the outer surface of the protective shell.

[0017] The beneficial effects of the above-described embodiments of this utility model are as follows:

[0018] This invention integrates a strain sensing system directly into the drill bit, enabling the device to acquire real-time deformation responses of the rock during drilling. The device utilizes high-precision resistance strain gauges in conjunction with a Wheatstone bridge circuit to detect deformations at the micro-strain level, ensuring data accuracy. Simultaneously, the wireless transmission module avoids the wiring difficulties and signal interference problems associated with traditional wired monitoring, allowing for stable data transmission to the ground receiving system. This in-situ real-time monitoring capability not only significantly shortens the testing cycle but, more importantly, provides dynamic decision-making support for engineering construction, effectively reducing construction risks.

[0019] This invention arranges transverse and longitudinal strain gauges on the inner wall of the protective shell to form an orthogonal measurement network, which can completely capture the axial and radial strain of the rock during drilling. First, the two sets of strain gauges work together to verify the reliability of the data. When one set of strain gauges shows an abnormality, the other set of data can still ensure the continuity of the test. Second, the orthogonally arranged strain gauges can eliminate measurement errors caused by drill bit eccentricity or uneven force, thus improving the accuracy of the data.

[0020] This utility model device can be directly installed between conventional drill rods and drill bits without modifying existing drilling equipment, making installation simple and highly compatible. On the other hand, the built-in annular sealed battery provides a stable power supply to the system, avoiding the hassle of external power sources, improving the device's applicability, and enabling it to meet the needs of various complex engineering environments, greatly expanding its application scope and value. Attached Figure Description

[0021] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments of this utility model and their descriptions are used to explain this utility model and do not constitute an improper limitation of this utility model.

[0022] Figure 1 This is a schematic diagram of the internal structure of the rapid testing device for rock deformation parameters of this utility model;

[0023] Figure 2 yes Figure 1 A magnified view of a section at point A in the middle;

[0024] Figure 3 This is a schematic diagram of the external signal receiving computer of this utility model.

[0025] The diagram is for illustrative purposes only.

[0026] The components include: 1. High-strength protective shell; 2. Internal threaded interface; 3. Ring power supply module; 4. Metal charging contact interface; 5. Resistance strain gauge assembly; 6. Working fixed resistor; 7. Internal power supply circuit; 8. Signal transmission circuit; 9. Branch fixed resistor; 10. Deformation parameter testing module; 11. Wireless transmission module; 12. Wireless signal transmitter; 13. Computer display window; and 14. Wireless signal receiver. Detailed Implementation

[0027] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The following table is... Figure 1 Legend:

[0028] Table 1 Legend

[0029]

[0030] Example 1

[0031] In a typical embodiment of this utility model, such as Figure 1-3 As shown, a rapid testing device for rock deformation parameters is provided, including a protective shell. One end of the protective shell is connected to the drill pipe, and the other end is connected to the drill bit. A power supply module, a resistance strain gauge group 5, a deformation parameter testing module 10, and a wireless transmission module 11 are installed inside the protective shell. The power supply module is connected to the resistance strain gauge group 5, the deformation parameter testing module 10, and the wireless transmission module 11 respectively through an internal power supply line 7. The internal power supply line 7 connecting the power supply module and the resistance strain gauge group 5 is connected to the deformation parameter testing module 10 through a signal transmission line 8.

[0032] The aforementioned rapid testing device for rock deformation parameters integrates power supply, sensing, calculation, and communication functions within the drill string through a modular design. It eliminates the need for complex external equipment and can be directly installed between the conventional drill pipe and drill bit. Suitable for confined downhole spaces and harsh environments, the resistance strain gauge group 5 senses the strain generated by the interaction between the drill string and the rock. The deformation parameter testing module 10 processes the data in real time and calculates Poisson's ratio, solving the lag problem of traditional methods that require offline testing after sampling. Furthermore, the built-in power supply module provides a stable energy source for the entire system, eliminating reliance on external power and making it suitable for long-term continuous operation.

[0033] In this embodiment, the protective shell is a circular tube. One end of the protective shell is connected to the drill bit by a thread, and the other end is connected to the drill rod by a thread. A hollow water passage hole is provided at the center of the protective shell, and the two ends of the hollow water passage hole are respectively connected to the water passage holes on the drill rod and the drill bit.

[0034] Specifically, the protective shell is made of high-strength alloy steel, with a wall thickness that meets the strength test requirements. It undergoes nitriding treatment to form a hardened layer, enhancing its wear and corrosion resistance. The shell surface is coated with a polyurethane waterproof coating to ensure airtightness. The high-strength protective shell 1 has threaded interfaces at both ends, connecting to the drill bit and drill rod via standard rock drilling internal thread interfaces 2. These internal thread interfaces 2 at both ends of the high-strength protective shell 1 match the external thread interfaces of the drill bit and the drill rod, allowing for a secure connection between the drill bit and drill rod. The high-strength protective shell 1 contains a hollow water passage hole that penetrates the shell. Both ends of the water passage hole connect to the corresponding interfaces of the drill bit and drill rod, ensuring leak-free coolant transmission, timely cooling of the drill bit, and assistance in slag removal.

[0035] In this embodiment, the power supply module is a toroidal lithium cobalt oxide battery. The power supply module adopts a fully sealed structure and is provided with a metal charging contact interface 4, which is embedded in the surface of the protective shell.

[0036] Specifically, a ring-shaped power supply module 3 is placed at the bottom inside the protective housing. This module, composed of a sealed lithium cobalt oxide battery, powers the internal resistance strain gauge group 5, the working fixed resistor 6, the deformation parameter testing module 10, and the wireless transmission module 11. A through-hole is located at the center of the ring-shaped power supply module 3's axis, coaxially connecting with the hollow holes of the high-strength protective housing, the drill bit, and the drill rod. The battery employs a fully sealed structure, with a waterproof sealing ring and an epoxy resin sealing layer on its outer surface. A metal charging contact interface 4 is located on one side of the battery. This interface is embedded in the surface of the high-strength protective housing and connected to the internal electrodes via an internal power supply line 7. The contact is protected by an anti-corrosion plating layer. Wireless charging is achieved by an external charging device contacting the contact, forming a closed circuit during charging.

[0037] Furthermore, a detachable protective cover is provided at the metal charging contact interface 4. The protective cover is fixed to the surface of the protective shell by threaded connection or magnetic attraction. A sealing ring is embedded on the inner side of the protective cover. The sealing ring is used to seal the metal charging contact interface 4 during drilling operations to prevent mud and water from entering. The outer surface of the protective cover is flush with the outer surface of the protective shell to avoid affecting the passability during the drilling process.

[0038] In this embodiment, the strain gauge group 5 is fixed to the inner wall of the protective housing. The strain gauge group 5 includes a transverse strain gauge and a longitudinal strain gauge, which are arranged perpendicularly. The transverse and longitudinal strain gauges are metal foil strain gauges. Two measuring points are equally spaced around the perimeter inside the high-strength protective housing 1, and a set of transverse and longitudinal strain gauges are arranged crosswise at each measuring point. The transverse strain gauge is fixed perpendicular to the drilling axis, and the longitudinal strain gauge is fixed parallel to the drilling axis. The two sets of strain gauges are symmetrically distributed on both sides of the drilling axis and fixed to the inner wall of the high-strength protective housing 1 by an epoxy resin adhesive layer. The epoxy resin adhesive layer is used to enhance the adhesion strength, insulation, and moisture-proof performance between the strain gauges and the inner wall of the housing.

[0039] In strain gauge testing, because the resistance change generated by the strain gauge itself is extremely small, it is measured using the voltage difference of a Wheatstone bridge. This bridge converts the minute resistance change of the strain gauge into a voltage change, thus enabling precise measurement. The circuit connection diagram is shown below. Figure 2As shown, the internal power supply line 7 connecting the resistance strain gauge group 5 to the power supply module includes a first voltage divider branch and a second voltage divider branch arranged in parallel. The midpoint voltage of the first voltage divider branch and the second voltage divider branch is connected to the deformation parameter testing module 10 via a data transmission line. A working fixed resistor 6 is provided on the first voltage divider branch. The working fixed resistor 6 is connected in series with the resistance strain gauge group 5 and then connected to the power supply module. Two branch fixed resistors 9 are provided on the second voltage divider branch. The two branch fixed resistors 9 are connected in series and then connected to the power supply module. The resistance values ​​of the working fixed resistor 6 and the branch fixed resistors 9 are both equal to the resistance of the resistance strain gauge group 5.

[0040] Specifically, the working fixed resistor 6 and the resistance strain gauge group 5 are connected in series through the internal power supply line 7 to form a voltage divider branch. The other two branch fixed resistors 9 are connected in series to form another voltage divider branch. Then, the two voltage divider branches are connected in parallel to form a parallel circuit. The strain measurement is achieved through the voltage difference at the midpoint of the two parallel branches. The resistance R1 of the resistance strain gauge group 5, the resistance R2 of the working fixed resistor 6, and the resistance values ​​of the two branch fixed resistors 9 R3 and R4 are the same, that is, R1=R2=R3=R4.

[0041] Among them, the working fixed resistor 6 is not affected by mechanical strain, and the parallel circuit remains stable when there is no strain change in the device. Equilibrium state. The resistance value of strain gauge group 5 changes by Δ only when subjected to strain. R strain Disruption of equilibrium conditions A voltage difference appears at the midpoint of the parallel branch, and the change in output voltage reflects the strain signal, thus realizing strain measurement. Wherein, Δ R strain This represents the change in resistance caused by strain.

[0042] The circuit works as follows: In the parallel circuit, the internal power supply line 7 starts from the positive terminal of the ring power supply module 3. The two internal power supply lines 7 are connected to the transverse strain gauge and the longitudinal strain gauge, respectively. One internal power supply line 7 is connected to the transverse strain gauge and connected in series with a working fixed resistor 6, and then connected in parallel with the voltage divider branch composed of two branch fixed resistors 9, returning to the negative terminal of the ring power supply module 3 through the internal power supply line 7; the other internal power supply line 7 is connected to the longitudinal strain gauge and connected in series with a working fixed resistor 6, and then connected in parallel with the voltage divider branch composed of two branch fixed resistors 9, returning to the negative terminal of the ring power supply module 3 through the internal power supply line 7.

[0043] The strain measurement results are transmitted via two parallel branches through the midpoint of the signal transmission line 8, and then input to the deformation parameter test module 10.

[0044] The working fixed resistor 6 and the branch fixed resistor 9 are fixed in the same axial plane as the resistance strain gauge group 5 and are located in the center of the symmetrically distributed resistance strain gauge group 5.

[0045] The high-strength protective shell houses a deformation parameter testing module 10. This module 10 uses the strain signal transmitted by the resistance strain gauge group 5 to calculate the deformation parameters of the rock being drilled, specifically the Poisson's ratio of the rock, based on the deformation parameter calculation equation. n .

[0046] The calculation formula for the rock deformation parameter calculation equation is as follows:

[0047]

[0048] in, n Poisson's ratio of the rock e 1 represents the strain parameters monitored by the longitudinal resistance strain gauge. e 2 represents the longitudinal strain parameter of the rock. e 3 represents the strain parameters monitored by the transverse resistance strain gauge. e 4 represents the transverse strain parameter of the rock. α The fitting coefficients for the longitudinal strain of the inner wall and the rock are given. β represents the lateral strain fitting coefficients for the inner wall and the rock.

[0049] The deformation parameter testing module 10 calculates the Poisson's ratio of the rock. n The signal is transmitted to the wireless transmission module 11 via signal transmission line 8.

[0050] The wireless transmission module 11 is connected to the deformation parameter testing module 10 via a signal transmission line 8, and is used to receive the Poisson's ratio of the rock calculated by the deformation parameter testing module 10. n The signal is transmitted outward via wireless transmitter 12, and received by wireless receiver 14 connected to the computer. The computer display window 13 displays the signal in real time, thus obtaining the Poisson's ratio of the rock. n Real-time curve of changes with drilling depth.

[0051] The working principle of the rapid testing device for rock deformation parameters provided in this embodiment is as follows:

[0052] The deformation characteristics of the rock during drilling are monitored in real time by a strain sensing system integrated inside the drill bit. Transverse and longitudinal resistance strain gauges are arranged crosswise on the inner wall of the protective casing of the device. The transverse strain gauges are perpendicular to the drilling axis to measure radial strain, while the longitudinal strain gauges are parallel to the drilling axis to measure axial strain. When the drill bit interacts with the rock, the resulting strain is transmitted to the strain gauges through the protective casing, causing changes in the strain gauge resistance. These strain signals are detected by a Wheatstone bridge circuit, which consists of strain gauges and fixed resistors. When strain causes the bridge to become unbalanced, a corresponding voltage difference signal is generated. After receiving these voltage signals, the deformation parameter testing module 10 calculates the Poisson's ratio of the rock in real time according to the preset rock deformation parameter calculation equation and the experimentally calibrated strain transfer coefficient. The calculated parameters are transmitted to the ground receiving device via the wireless transmission module 11, and finally displayed on the computer as a curve of rock mechanical parameters varying with drilling depth.

[0053] The entire system is powered by a built-in annular sealed battery and maintains cooling circulation through hollow water-permeable holes in the protective casing, ensuring stable operation in harsh drilling environments. This design enables in-situ, real-time, and rapid testing of rock mechanical parameters, providing crucial technical support for underground engineering construction.

[0054] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A device for rapid testing of rock deformation parameters, characterized in that, The system includes a protective housing, one end of which is connected to the drill pipe and the other end to the drill bit. Inside the protective housing are installed a power supply module, a resistance strain gauge assembly, a deformation parameter testing module, and a wireless transmission module. The power supply module is connected to the resistance strain gauge assembly, the deformation parameter testing module, and the wireless transmission module via internal power supply lines. The internal power supply line connecting the power supply module and the resistance strain gauge assembly is connected to the deformation parameter testing module via a signal transmission line. The deformation parameter testing module is electrically connected to the wireless transmission module.

2. The apparatus for rapid testing of rock deformation parameters according to claim 1, characterized in that, The resistance strain gauge assembly is fixed to the inner wall of the protective housing. The resistance strain gauge assembly includes a transverse strain gauge and a longitudinal strain gauge, which are arranged vertically.

3. The apparatus for rapid testing of rock deformation parameters according to claim 2, characterized in that, The transverse strain gauge is perpendicular to the drilling axis, and the longitudinal strain gauge is parallel to the drilling axis.

4. The rapid testing device for rock deformation parameters as described in claim 1, characterized in that, The resistance strain gauge group is provided in two sets, and the two sets of resistance strain gauges are equally spaced in the circumferential direction of the protective shell.

5. The rapid testing device for rock deformation parameters as described in claim 1, characterized in that, The internal power supply line connecting the resistance strain gauge group to the power supply module includes a first voltage divider branch and a second voltage divider branch arranged in parallel. The midpoint voltage of the first voltage divider branch and the second voltage divider branch is connected to the deformation parameter testing module through a data transmission line.

6. The rapid testing device for rock deformation parameters as described in claim 5, characterized in that, A working fixed resistor is provided on the first voltage divider branch. The working fixed resistor is connected in series with the strain gauge group and then connected to the power supply module. Two branch fixed resistors are provided on the second voltage divider branch. The two branch fixed resistors are connected in series and then connected to the power supply module.

7. The rapid testing device for rock deformation parameters as described in claim 6, characterized in that, The resistance values ​​of both the working fixed resistor and the branch fixed resistor are equal to the resistance of the strain gauge assembly.

8. The rapid testing device for rock deformation parameters as described in claim 1, characterized in that, The protective shell is a circular tube. One end of the protective shell is connected to the drill bit by a thread, and the other end is connected to the drill rod by a thread. A hollow water passage hole is provided at the center of the protective shell, and the two ends of the hollow water passage hole are respectively connected to the water passage holes on the drill rod and the drill bit.

9. The rapid testing device for rock deformation parameters as described in claim 8, characterized in that, The power supply module is a toroidal lithium cobalt oxide battery. The power supply module adopts a fully sealed structure and is provided with a metal charging contact interface, which is embedded in the surface of the protective shell.

10. The rapid testing device for rock deformation parameters as described in claim 9, characterized in that, A detachable protective cover is provided at the metal charging contact interface. The protective cover is fixed to the surface of the protective shell by screwing or magnetic attraction. A sealing ring is embedded on the inner side of the protective cover, and the outer surface of the protective cover is flush with the outer surface of the protective shell.

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