A rock drill while drilling parameter measurement device and a method for calculating rock compressive strength

Abstract

The present invention discloses a rock drill parameter measurement device and a method for calculating the rock compressive strength, belonging to the field of load testing technology; the rock drill parameter measurement device detects corresponding stress and strain by circumferentially attaching a first strain gauge, a second strain gauge, a third strain gauge and a fourth strain gauge at the connection between the tail of the drill rod and the connecting sleeve, and obtains corresponding stress wave and other data according to the stress and strain. The corresponding torque data is detected by arranging a fifth strain gauge and a sixth strain gauge at intervals with the first strain gauge and the fourth strain gauge. Thus, the unexcavated rock mass related data is obtained. Compared with the prior art, the measurement data of the measurement device takes into account both accuracy and advancement.

Description

Technical Field

[0001] The invention belongs to the technical field of load testing, and in particular relates to a device for measuring drilling parameters of a rock drill and a method for calculating the compressive strength of rocks. Background Art

[0002] The rock mass contains various structures of different rock types and is filled with a large number of randomly distributed structural surfaces and cracks. The current survey methods can only give a rough classification of the surrounding rock. Only when the rock mass is exposed after tunnel excavation, the detailed rock mass conditions can be determined based on the exposed rock mass. Although the obtained rock mass data is relatively detailed, this data can only be obtained after tunnel excavation, that is, detailed rock mass data cannot be obtained before tunnel excavation, resulting in data lag.

[0003] To this end, existing technicians use advanced forecasting methods such as geological radar to predict the rock mass in front of the face to ensure that rock mass data can be obtained before tunnel excavation. However, this rock mass data still has a large error compared to the data measured based on exposed rock mass.

[0004] In summary, the existing methods for obtaining rock mass data cannot take into account both the accuracy and advancement of rock mass data. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a rock drill while drilling parameter measurement device and a method for calculating the compressive strength of rock in view of the deficiencies in the above-mentioned prior art, which has a novel and reasonable design, a simple structure, high measurement accuracy and is easy to promote and use.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A drilling parameter measurement device for a rock drill, the rock drill comprising a base, two support rods arranged on the base and a disc arranged on the two support rods, a guide rail beam arranged on the disc and a pneumatic rock drill body arranged on the guide rail beam and capable of moving along the guide rail beam, a drill rod is passed through the pneumatic rock drill body, a connecting sleeve is arranged at the tail of the drill rod, a drill rod is installed in the connecting sleeve, a fiber pincher is arranged near the drill bit on the guide rail beam, the drill rod passes through the fiber pincher, the measuring device comprises an axial force measuring module and a torque measuring module arranged at the connection between the tail of the drill rod and the connecting sleeve, a rotation speed measuring module for detecting the rotation speed of the drill rod, and a drilling depth measuring module for detecting the drilling depth;

[0008] The axial force measurement module comprises a first strain gauge, a second strain gauge, a third strain gauge and a fourth strain gauge which are circumferentially attached to the connection between the tail of the drill rod and the connecting sleeve, the length direction of the first strain gauge and the third strain gauge are arranged along the axial direction, and the length direction of the second strain gauge and the fourth strain gauge are arranged perpendicular to the axial direction; the first strain gauge, the second strain gauge, the third strain gauge and the fourth strain gauge are connected to form a first full-bridge measurement circuit;

[0009] The torque measurement module includes a fifth strain gauge and a sixth strain gauge which are circumferentially arranged along the connection between the tail of the drill rod and the connecting sleeve. The length directions of the fifth strain gauge and the sixth strain gauge are arranged axially. The fifth strain gauge and the sixth strain gauge are arranged at intervals from the first strain gauge and the fourth strain gauge. The fifth strain gauge, the sixth strain gauge and two non-inductive resistors are connected to form a second full-bridge measurement circuit.

[0010] Furthermore, the rotation speed measurement module includes an L-shaped plate arranged on the pneumatic rock drill body, a magnetic steel arranged on the L-shaped plate, a collection box glued on the connecting sleeve, and a Hall sensor arranged on the side of the collection box close to the magnetic steel; the drill rod rotation speed is determined according to the output voltage of the Hall sensor;

[0011] A strain gauge acquisition module is arranged in the acquisition box, and the first strain gauge, the second strain gauge, the third strain gauge, the fourth strain gauge, the fifth strain gauge and the sixth strain gauge are all connected to the strain gauge acquisition module.

[0012] Furthermore, the drilling depth measurement module is a wire displacement meter arranged on the L-shaped plate, the end of the measuring rope of the wire displacement meter is connected to the fiber pincher, and the wire displacement meter is used to measure the drilling displacement.

[0013] Furthermore, the wire displacement meter and the strain gauge acquisition module are both connected to a wireless dynamic strain gauge, and the wireless dynamic strain gauge is connected to a computer via a wireless AP module.

[0014] The present invention also discloses a method for calculating the compressive strength of rock, which comprises the following steps: using the above-mentioned rock drill while drilling parameter measurement device to measure data, and determining the compressive strength according to the measured data, wherein the measured data comprises the cross-sectional area at the drill tail bonding piece, incident wave energy, transmitted wave energy and reflected wave energy;

[0015] Obtain the proportional coefficient of axial force work, the proportional coefficient of propulsion work, the proportional coefficient of torque work, propulsion force rock breaking energy, drilling speed, drill bit area and drilling time to determine the delayed compressive strength;

[0016] The calculation formula of the compressive strength is:

[0017]

[0018] Among them, W I is the axial rock breaking energy, W P is the propulsion rock breaking energy, W R is the torque rock breaking energy, K1 is the proportional coefficient of axial force work, K2 is the proportional coefficient of thrust work, K3 is the proportional coefficient of torque work, v is the drilling speed, A2 is the drill bit area, t is the drilling time, and K is the proportional coefficient of drilling specific energy and compressive strength;

[0019] The calculation formula of the axial force rock breaking energy is:

[0020]

[0021] Among them, A1 is the cross-sectional area of ​​the shank where the shank is attached to the sheet, c0 is the propagation speed of the stress wave in the shank and the drill pipe, E is the elastic modulus of the shank, t is the drilling time, σ rs is the incident wave energy, σ zs is the transmitted wave energy, σ fs is the reflected wave energy;

[0022] The calculation formula of the torque rock breaking energy is:

[0023] W R =2πnM-W0-W rf -W f

[0024] Where M is the drill pipe torque, n is the drill pipe speed, W0 is the torque work generated by idling, and W rf is the work done by friction between the drill pipe and the rock wall, W f The energy required to overcome the friction between the drill bit and the bottom of the hole;

[0025] The calculation formula of the propulsion rock breaking energy is:

[0026] W P =F P ×h P

[0027] Among them, F P is the propulsion force, h P is the pressing depth.

[0028] Furthermore, the process for determining the proportional coefficient of axial force work, the proportional coefficient of propulsion force work, the proportional coefficient of torque work, and the proportional coefficient of drilling specific energy and compressive strength is as follows: core drilling is performed within a set length range around the side hole while drilling, the taken cores are arranged according to the drilling depth, and the cores are subjected to uniaxial compressive strength tests and point load tests to obtain corresponding compressive strength, axial force rock-breaking energy, propulsion force rock-breaking energy, torque rock-breaking energy, drilling speed, drill bit (14) area and drilling time data; multiple linear regression fitting is performed on the experimental data according to the calculation formula of compressive strength to obtain the corresponding proportional coefficient of axial force work, propulsion force work, torque work, and the proportional coefficient of drilling specific energy and compressive strength.

[0029] Furthermore, the measurement data also includes the drill pipe rotation speed.

[0030] Furthermore, the measurement data also includes the drilling depth and the penetration depth. The drilling speed is determined according to the drilling depth. The calculation formula of the drilling speed is:

[0031]

[0032] Among them, h i is the drilling depth at time i, t i is the sampling time at time i, h i is the drilling depth at time i, t i is the sampling time at time i.

[0033] Furthermore, the drilling depth and the penetration depth are preprocessed data, and the preprocessing process is: using the sym8 wavelet function to filter the measured data, reducing the noise of the filtered data, and when missing data is detected, using the adjacent data linear interpolation method to determine the data to be filled.

[0034] Furthermore, the calculation formula of drill pipe torque is:

[0035] M=G0×γ

[0036] Among them, G0 is the shear modulus of the shank, and γ is the shear strain of the cross section of the shank.

[0037] Compared with the prior art, the present invention has the following advantages:

[0038] The rock drill parameter measurement device of the present invention detects the corresponding stress and strain by circumferentially attaching the first strain gauge, the second strain gauge, the third strain gauge and the fourth strain gauge at the connection between the tail of the drill rod and the connecting sleeve, and obtains the corresponding stress wave and other data according to the stress and strain. The fifth strain gauge and the sixth strain gauge are arranged at intervals with the first strain gauge and the fourth strain gauge to detect the corresponding torque data. In this way, the relevant data of the unexcavated rock mass is obtained. Compared with the prior art, the measurement data of the measurement device takes into account both accuracy and advancement.

[0039] The method for calculating the rock compressive strength of the present invention calculates the corresponding compressive strength by utilizing the measurement data of the drilling parameter measurement device of the rock drill, which not only ensures the accuracy of the compressive strength data, but also facilitates researchers to conduct research and analysis based on the rock compressive strength in a timely manner.

[0040] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of the overall structure of an embodiment of a device for measuring parameters while drilling a rock drill according to the present invention;

[0042] Figure 2 A schematic cross-sectional view of a drill rod of an embodiment of a device for measuring parameters while drilling a rock drill according to the present invention;

[0043] Figure 3 A schematic diagram of a first full-bridge measurement circuit of an embodiment of a device for measuring parameters while drilling a rock drill according to the present invention;

[0044] Figure 4 A schematic diagram of a second full-bridge measurement circuit of an embodiment of a device for measuring parameters while drilling a rock drill according to the present invention;

[0045] Figure 5 A Hall sensor measurement principle diagram of an embodiment of a device for measuring parameters while drilling a rock drill according to the present invention;

[0046] Figure 6 It is a block diagram of the composition of an embodiment of the device for measuring parameters while drilling a rock drill according to the present invention;

[0047] Figure 7 It is a diagram of experimental results of an embodiment of the device for measuring parameters while drilling a rock drill according to the present invention;

[0048] Description of reference numerals:

[0049] 1. Connecting sleeve; 2. Magnetic steel; 3. L-shaped plate; 4. Wire displacement meter;

[0050] 5. Pneumatic rock drill body; 6. Hall sensor; 7. Disc; 8. Guide rail beam;

[0051] 9. Axial force measurement module; 9-1. First strain gauge; 9-2. Second strain gauge; 9-3. Third strain gauge; 9-4. Fourth strain gauge;

[0052] 10. Torque measurement module; 10-1. Fifth strain gauge; 10-2. Sixth strain gauge;

[0053] 11. Collection box; 12. Drill rod; 13. Fiber pincher; 14. Drill bit; 15. Base; 16. Drill rod. DETAILED DESCRIPTION

[0054] Embodiment of the device for measuring parameters while drilling a rock drill:

[0055] Considering that the existing methods of obtaining rock mass data cannot take into account both accuracy and advanceness because the exposed rock mass cannot be accessed before excavation; combined with the fact that a large amount of drilling work needs to be carried out before tunnel excavation, such as advance small guide tubes, pipe rack drilling, anchor drilling, and blasting charge drilling, these works can contact the real rock mass during drilling, that is, the real rock mass can be contacted before excavation.

[0056] To solve the above problems, Figure 1 The rock drill parameter measurement device shown in the figure comprises a base 15, two support rods arranged on the base 15 and a disc 7 arranged on the two support rods, a guide rail beam 8 arranged on the disc 7 and a pneumatic rock drill body 5 arranged on the guide rail beam 8 and movable along the guide rail beam 8, a drill rod 16 is passed through the pneumatic rock drill body 5, a connecting sleeve 1 is arranged at the tail of the drill rod 16, a drill rod 12 is installed in the connecting sleeve 1, a fiber pincher 13 is arranged at the end of the guide rail beam 8 near the drill rod 12, and the drill rod 12 passes through the fiber pincher 13. Secondly, the measuring device comprises an axial force measuring module 9 and a torque measuring module 10 arranged at the connection between the tail of the drill rod 16 and the connecting sleeve 1, a rotation speed measuring module for detecting the rotation speed of the drill rod 12, and a drilling depth measuring module for detecting the drilling depth.

[0057] like Figure 3As shown, the axial force measurement module 9 includes a first strain gauge 9-1, a second strain gauge 9-2, a third strain gauge 9-3 and a fourth strain gauge 9-4 which are circumferentially attached to the connection between the tail of the drill rod 16 and the connecting sleeve 1. The length direction of the first strain gauge 9-1 and the third strain gauge 9-3 is arranged along the axial direction, and the length direction of the second strain gauge 9-2 and the fourth strain gauge 9-4 is arranged perpendicular to the axial direction. Specifically, the first strain gauge 9-1, the second strain gauge 9-2, the third strain gauge 9-3 and the fourth strain gauge 9-4 are connected to form a first full-bridge measurement circuit according to the Wheatstone bridge. The output voltage U0 and the power supply voltage U1 of the first full-bridge measurement circuit are measured. The cross section of the drill tail of the rock drill is a cylinder, so the middle section with a small cross-section change is selected for strain measurement. The first strain gauge 9-1, the second strain gauge 9-2, the third strain gauge 9-3 and the fourth strain gauge 9-4 use BE120-3AA type strain gauges. Figure 3 R1, R2, R3 and R4 are the first strain gauge 9-1, the second strain gauge 9-2, the third strain gauge 9-3 and the fourth strain gauge 9-4 respectively. The R1 and R2 strain gauges are arranged at 0 degrees and 180 degrees along the axis direction respectively, and play the role of axial force measurement. The R3 and R4 strain gauges are arranged at 90 degrees and 270 degrees perpendicular to the axis direction respectively, and play a compensation role, which can eliminate the influence of temperature and bending moment on the measurement results. According to the full-bridge detection circuit, the corresponding stress wave, that is, the corresponding incident wave, transmitted wave and reflected wave can be obtained.

[0058] like Figure 4 As shown, the torque measurement module 10 includes a fifth strain gauge 10-1 and a sixth strain gauge 10-2 which are circumferentially attached to the connection between the tail of the drill rod 16 and the connecting sleeve 1. The length direction of the fifth strain gauge 10-1 and the sixth strain gauge 10-2 is arranged along the axial direction. The fifth strain gauge 10-1 and the sixth strain gauge 10-2 are arranged at intervals from the first strain gauge 9-1 and the fourth strain gauge 9-4. The fifth strain gauge 10-1, the sixth strain gauge 10-2 and two non-inductive resistors are connected to form a second full-bridge measurement circuit according to the Wheatstone bridge. The fifth strain gauge 10-1 and the sixth strain gauge 10-2 are BE120-2HA type strain gauges. Figure 4 Medium, R5 45° and R5 135° The fifth strain gauge 10-1 and the sixth strain gauge 10-2 are respectively, preferably, in order to increase the output signal and reduce the influence of temperature change on the test result, R5 45° and R5 135° The resistances are equal, and the other two unmarked resistors are non-inductive resistors.

[0059] like Figure 1As shown, the speed measurement module includes an L-shaped plate 3 arranged on the pneumatic rock drill body 5, a magnetic steel 2 arranged on the L-shaped plate 3, a collection box 11 bonded to the connecting sleeve 1, and a Hall sensor 6 arranged on the side of the collection box 11 close to the magnetic steel 2. The Hall sensor 6 senses the change of the magnetic field under the action of the external magnetic steel 2, and determines the corresponding rotation speed of the drill rod 12 according to the induced electromotive force signal, that is, the rotation speed of the drill rod 12 is determined according to the output voltage of the Hall sensor 6. In addition, Figure 5 As shown, due to the limitation of the sensitive range of magnetic flux change, the effective sensing distance between the magnet 2 and the sensor is about 10 mm, so an L-shaped plate 3 is designed to install the magnet 2 to ensure the sensing effect of the Hall sensor 6.

[0060] like Figure 5 As shown, the detection principle of the Hall sensor 6 is as follows: When the Hall sensor 6 is placed in a magnetic field, the magnetic flux lines exert a force on the semiconductor material, causing the carriers, electrons and holes to be deflected to either side of the semiconductor plate. This movement of the charge carriers is the result of the magnetic force they experience when passing through the semiconductor material. When these electrons and holes move to the side, a potential difference is generated between the two sides of the semiconductor material due to the accumulation of these charge carriers. The movement of electrons through the semiconductor material is then affected by the external magnetic field at right angles to it, and this effect is greater in flat rectangular materials. The Hall effect provides information about the type of magnetic pole and the magnitude of the magnetic field. For example, the south pole will cause the device to produce a voltage output, while the north pole will have no effect. Typically, Hall effect sensors and switches are designed to be in the "off" state (open circuit state) when there is no magnetic field. They will only be "open" when they are subjected to a magnetic field of sufficient strength and polarity. When there is no magnetic field (0V), the positive position detector will be "off". When the permanent magnet south pole (positive Gauss) moves vertically to the active area of ​​the Hall effect sensor, the device will be "on" and light up the LED. Once switched "ON", the Hall Effect Sensor will remain "ON".

[0061] In order to facilitate the collection of strain of the strain gauge, a strain gauge collection module is provided in the collection box 11, and the first strain gauge 9-1, the second strain gauge 9-2, the third strain gauge 9-3 and the fourth strain gauge 9-4 as well as the fifth strain gauge 10-1 and the sixth strain gauge 10-2 are all connected to the strain gauge collection module.

[0062] In order to be suitable for the high-concentration dust working environment in the tunnel, the drilling depth measurement module is a wire displacement meter 4 set on the L-shaped plate 3. The end of the measuring rope of the wire displacement meter 4 is connected to the fiber pincher 13. The wire displacement meter 4 is used to measure the drilling displacement. Specifically, a hook is installed on the top of the fiber pincher 13 to fix the measuring rope of the wire displacement meter 4. The wire pulling direction is adjusted to be parallel to the direction of the drill rod 12 by the gasket to ensure the accuracy of the measurement. The measured rock drill stroke is the forward amount. The wire displacement meter 4 needs to be pulled out to a certain length in advance. The drilling displacement is measured by the length contraction of the rope of the wire displacement meter 4, and then the drilling depth data is obtained. Among them, the maximum drilling stroke of the rock drill is 1.2m, and the length of a single section of the drill rod 12 is 1m. When drilling 1m, the drill rod 12 needs to be added, so the single measurement length does not exceed 1m. The maximum range of the wire displacement meter 4 is 1000mm, which can meet the measurement requirements.

[0063] Preferably, the wire displacement meter 4 adopts a 5G104 wire displacement sensor. The wire displacement sensor is more suitable for the high-concentration dust working environment in the tunnel than the laser displacement sensor, and can ensure stable measurement of drilling depth and drilling speed.

[0064] like Figure 6 As shown, in order to reduce the space occupied by the equipment, the wire displacement meter 4 and the strain gauge acquisition module are connected to the wireless dynamic strain gauge; the wireless dynamic strain gauge is connected to the computer through the wireless AP module. The data measured by the measuring device can be obtained through the computer. Among them, the wire displacement meter 4 is directly connected to the dynamic strain gauge through the data line, and the collected information is output through the voltage, which ensures the stability of the test data. The voltage sensitivity is 0.0024mv / mm, and the minimum scale can identify the displacement change of 1mm, which has the characteristics of high precision. The device includes a control system, a drilling parameter test part, a wireless transmission part and a signal processing part; wherein the control system includes a propulsion push rod for controlling the propulsion force, an impact push rod for controlling the idling torque and a rotary push rod for controlling the speed; the data that can be measured by the drilling parameter part include axial force, torque, speed, drilling depth and drilling speed; the wireless transmission part includes a wireless dynamic strain gauge and a wireless AP, and the signal processing includes a computer and software running on the computer. Figure 6 The axial force in is the axial force in this application.

[0065] During use, the test site will correctly install the corresponding drill tail, and then use a multimeter to test the strain gauge lead resistance according to the Wheatstone bridge principle to ensure the normal operation of the monitoring system. After that, take waterproof, dustproof and rockfall prevention measures at the wire connection location; turn on all measuring components, dynamic strain gauges, wireless AP routers and monitoring software on the computer to confirm that all signals are transmitted and received normally; after the system test is completed. To conduct a test experiment on the rock drill's drilling parameter measurement device, it is necessary to first determine the basic working parameters of the rock drill, among which the main test variables such as the rock drill's thrust, impact force, drill rod 12 rotation speed and drill rod 12 torque can be combined with the equipment inspection report and controlled according to the input constant air pressure. At the same time, the thrust, impact force, drill rod 12 rotation speed and torque can be controlled separately by the joystick; the specific test results are as follows Figure 7 shown.

[0066] Example of calculation method for rock compressive strength:

[0067] In order to improve the accuracy of compressive strength calculation, the calculation method of rock compressive strength includes the following steps: using the above-mentioned rock drill drilling parameter measurement device embodiment to measure data, and determining the axial force rock breaking energy and torque rock breaking energy according to the measurement data, and the measurement data includes the cross-sectional area of ​​the drill tail at the bonding piece, the incident wave energy, the transmitted wave energy and the reflected wave energy.

[0068] The delayed compressive strength is determined by obtaining the proportional coefficient of axial force work, the proportional coefficient of propulsion work, the proportional coefficient of torque work, propulsion force rock breaking energy, drilling speed, drill bit 14 area and drilling time. The calculation formula of the compressive strength is:

[0069]

[0070] Among them, W I is the axial rock breaking energy, W P is the propulsion rock breaking energy, W R is the torque rock-breaking energy, K1 is the proportional coefficient of axial force work, K2 is the proportional coefficient of thrust work, K3 is the proportional coefficient of torque work, v is the drilling speed, A2 is the area of ​​drill bit 14, t is the drilling time, and K is the proportional coefficient of drilling specific energy and compressive strength.

[0071] Specifically, the calculation formula of axial force rock breaking energy is:

[0072]

[0073] Among them, A1 is the cross-sectional area of ​​the shank where the shank is attached to the sheet, c0 is the propagation speed of the stress wave in the shank and the drill pipe 12, E is the elastic modulus of the shank, t is the drilling time, σ rs is the incident wave energy, σ zsis the transmitted wave energy, σf s The strain gauges in the cross-sectional area of ​​the shank where the strain gauges are attached refer to the first strain gauge 9-1, the second strain gauge 9-2, the third strain gauge 9-3 and the fourth strain gauge 9-4.

[0074] The calculation formula of torque rock breaking energy is:

[0075] W R =2πnM-W0-W rf -W f

[0076] Wherein, M is the torque of the drill rod 12, n is the rotation speed of the drill rod 12, W0 is the torque work generated by idling, and W rf is the friction work between the drill pipe 12 and the rock wall, W f The energy required to overcome the friction between the drill bit 14 and the bottom of the borehole.

[0077] The calculation formula of propulsion rock breaking energy is:

[0078] W P =F P ×h P

[0079] Among them, F P is the propulsion force, h P is the pressing depth.

[0080] Among them, the determination process of the proportional coefficient of axial force work, the proportional coefficient of propulsion force work, the proportional coefficient of torque work, and the proportional coefficient of drilling specific energy and compressive strength is as follows: drilling and coring is performed within a set length range around the side hole while drilling, the cores taken out are arranged according to the drilling depth, and the cores are subjected to uniaxial compressive strength test and point load test to obtain the corresponding compressive strength, axial force rock breaking energy, propulsion force rock breaking energy, torque rock breaking energy, drilling speed, drill bit 14 area and drilling time data, and the data obtained from the experiment are subjected to multivariate linear regression fitting according to the calculation formula of compressive strength to obtain the corresponding proportional coefficient of axial force work, propulsion force work, torque work, and the proportional coefficient of drilling specific energy and compressive strength. Preferably, the set length is 10 cm, and the core hole diameter of the drilling and coring is 5 cm.

[0081] After multiple linear regression fitting, the coefficient of determination is R 2 =0.913, it has a good confidence level, and the registration fits the test data well. The corresponding calculation formula for compressive strength is:

[0082]

[0083] In order to further improve the accuracy of calculating the compressive strength, the above-mentioned measurement data also includes the rotation speed of the drill rod 12 for calculating the torque rock breaking energy, which is specifically obtained according to the rotation speed measurement module of the embodiment of the above-mentioned rock drill while drilling parameter measurement device.

[0084] The above measurement data also includes drilling depth and penetration depth. The drilling speed is determined according to the drilling depth. Specifically, the calculation formula of the drilling speed is:

[0085]

[0086] Among them, h i is the drilling depth at time i, t i is the sampling time at time i, h i is the drilling depth at time i, t i is the sampling time at time i.

[0087] In order to ensure the integrity and availability of the data, the drilling depth and the penetration depth are preprocessed data. The preprocessing process is: use the sym8 wavelet function to filter the measured data, reduce the noise of the filtered data, and when missing data is detected, use the adjacent data linear interpolation method to determine the data to be filled. Specifically, after manually filtering out the net drilling process measurement data, the Matlab software wavelet threshold denoising algorithm is used to perform basic noise reduction on the filtered data, that is, by adjusting the wavelet decomposition layer number, threshold, threshold function and wavelet basis, the wavelet denoising of the drilling data is completed. For missing data, combined with the sensor sampling rate, it is filled by linear interpolation of adjacent data; the relevant source code is as follows.

[0088] % Assume A and B are two columns of data

[0089] A=H1;

[0090] B = T1;

[0091] % Initialize a logical array to mark the elements in column A that need to be retained

[0092] keep = true(size(A));

[0093] % Loop until all data in column A is arranged from small to large

[0094] is true

[0095] % Mark the elements that need to be removed

[0096]

[0097] % If no element is found to be removed, exit the loop

[0098] if all(keep)

[0099] break;

[0100] end

[0101] % Use the keep array to update columns A and B

[0102] A=A(keep);

[0103] B = B (keep);

[0104] keep=true(size(A)); % Reset the keep array for the next round of checking

[0105] end

[0106] % Display processed data

[0107] disp('Processed A:');

[0108] disp(A);

[0109] disp('Processed B:');

[0110] disp(B);

[0111] Instantaneous drilling speed calculation:

[0112] % Example Data Points

[0113] x = B;

[0114] y = A;

[0115] % Calculate the slope between adjacent points

[0116] dx = diff(x); % Calculate the difference of x

[0117] dy=diff(y); %Calculate the difference of y

[0118] slopes=dy. / dx;%Calculate the slope (Note: For the point where the difference of x is 0, special treatment is required) Segment average drilling speed calculation:

[0119] % Assume that A and B are two vectors, representing depth data and time data respectively

[0120] %Define segmentation criteria

[0121] segment_size = 10; % 10 mm is one segment

[0122] % Initialize variables

[0123] num_segments = floor(max(A) / segment_size); % Calculate the number of segments avg_drilling_speed = zeros(1,num_segments); % Store the average drilling speed of each segment

[0124] %Traverse each segment

[0125] for i=1:num_segments

[0126] %Get the depth range of the current segment

[0127] lower_bound=(i-1)*segment_size+1;

[0128] upper_bound=i*segment_size;

[0129] % Find the depth data and corresponding time data within the current segment range

[0130] depth_in_segment=A(A>=lower_bound&A<=upper_bound);

[0131] time_in_segment=B(A>=lower_bound&A<=upper_bound);

[0132] % Calculate the average drilling speed of the current segment

[0133] avg_drilling_speed(i)=mean(diff(depth_in_segment). / diff(time_in_segment));

[0134] end

[0135] % Output results

[0136] disp('Average drilling speed for each segment:');

[0137] disp(avg_drilling_speed);

[0138] The above code represents the specific process of preprocessing and calculating drilling speed.

[0139] Among them, the calculation formula of the torque of the drill rod 12 is:

[0140] M=G0×γ

[0141] Among them, G0 is the shear modulus of the shank, and γ is the shear strain of the cross section of the shank.

[0142] Specifically, the process of establishing the calculation formula of compressive strength is as follows: First, the basic energy equation of the rock drill can be constructed by combining the specific energy as follows:

[0143] SE×v×A2×t=K1W I +K2W P +K3W R +E ε

[0144] Where: SE is drilling specific energy, W I is the axial rock breaking energy, W P is the propulsion rock breaking energy, W R is the torque rock breaking energy, K1 is the proportional coefficient of axial force work, K2 is the proportional coefficient of propulsion work, K3 is the proportional coefficient of torque work, E ε is the sound, light, heat and other energies generated during the drilling process, and v is the drilling speed. Since other energies such as sound, light and heat are generally very small, they are omitted in the calculation. And because the drilling specific energy SE can largely reflect the properties of the drilled rock mass, it can be used as a key indicator to measure the mechanical properties of rock and the working performance of the rock drill. From a dimensional perspective, the specific energy is consistent with the stress, and there is a linear relationship between the drilling specific energy and the uniaxial compressive strength of the rock. Taking the linear coefficient as K, the following relationship can be obtained:

[0145] SE=K×σ c

[0146] Where SE is the drilling specific energy, σ c is the compressive strength. Combining the basic energy equation of the rock drill, the following relationship can be obtained: K×σ c ×v×A2×t=K1W I +K2W P +K3W R , and then the formula for calculating the compressive strength of this application can be obtained.

[0147] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for calculating the compressive strength of rock, characterized in that: The method comprises the following steps: data measurement, determining the compressive strength according to the measured data, wherein the measured data comprises the cross-sectional area of ​​the solder tail at the bonding sheet, incident wave energy, transmitted wave energy and reflected wave energy; Obtain the proportional coefficient of axial force work, the proportional coefficient of propulsion work, the proportional coefficient of torque work, propulsion force rock breaking energy, drilling speed, drill bit area and drilling time to determine the delayed compressive strength; The calculation formula of the compressive strength is: Among them, W I is the axial force rock breaking energy, W P is the propulsion rock breaking energy, W R is the torque rock-breaking energy, K1 is the proportional coefficient of axial force work, K2 is the proportional coefficient of thrust work, K3 is the proportional coefficient of torque work, v is the drilling speed, A2 is the area of ​​the drill bit (14), t is the drilling time, and K is the proportional coefficient of drilling specific energy and compressive strength; The calculation formula of the axial force rock breaking energy is: Where A1 is the cross-sectional area of ​​the shank where the shank is attached to the plate, c0 is the propagation speed of the stress wave in the shank and the drill pipe (12), E is the elastic modulus of the shank, t is the drilling time, σ rs is the incident wave energy, σ zs is the transmitted wave energy, σ fs is the reflected wave energy; The calculation formula of the torque rock breaking energy is: IN R =2πnM-W0-W rf -IN f Where M is the torque of the drill pipe (12), n is the drill pipe speed, W0 is the torque work generated by idling, and W rf is the friction work between the drill pipe (12) and the rock wall, W f The energy required to overcome the friction between the drill bit and the bottom of the hole; The calculation formula of the propulsion rock breaking energy is: W P =F P ×h P Among them, F P is the propulsion force, h P is the penetration depth; The process for determining the proportional coefficient of axial force work, the proportional coefficient of propulsion force work, the proportional coefficient of torque work, and the proportional coefficient of drilling specific energy and compressive strength is as follows: drilling and coring is performed within a set length range around the side hole while drilling, the taken cores are arranged according to the drilling depth, and the cores are subjected to uniaxial compressive strength tests and point load tests to obtain corresponding compressive strength, axial force rock-breaking energy, propulsion force rock-breaking energy, torque rock-breaking energy, drilling speed, drill bit (14) area and drilling time data; and multiple linear regression fitting is performed on the experimental data according to the calculation formula of compressive strength to obtain the corresponding proportional coefficient of axial force work, the proportional coefficient of propulsion force work, the proportional coefficient of torque work, and the proportional coefficient of drilling specific energy and compressive strength.

2. A method for calculating rock compressive strength according to claim 1, characterized in that: The measurement data also includes the rotation speed of the drill pipe (12).

3. The method for calculating the compressive strength of rock according to claim 1, characterized in that: The measurement data also includes the drilling depth and the penetration depth. The drilling speed is determined according to the drilling depth. The calculation formula of the drilling speed is: Among them, h i is the drilling depth at time i, t i is the sampling time at time i, h i-1 is the drilling depth at time i-1, t i-1 is the sampling time at time i-1.

4. A method for calculating rock compressive strength according to claim 3, characterized in that: The drilling depth and the penetration depth are preprocessed data. The preprocessing process is: use the sym8 wavelet function to filter the measured data, reduce the noise of the filtered data, and when missing data is detected, use the adjacent data linear interpolation method to determine the data to be filled.

5. The method for calculating the compressive strength of rock according to claim 1, characterized in that: The calculation formula of the torque of the drill rod (12) is: M=G0×γ Among them, G0 is the shear modulus of the shank, and γ is the shear strain of the cross section of the shank.

6. The method for calculating rock compressive strength according to claim 1, characterized in that: The data measurement is performed using a rock drill while drilling parameter measurement device, the rock drill comprising a base (15), two support rods arranged on the base (15), a disc (7) arranged on the two support rods, a guide rail beam (8) arranged on the disc (7), and a pneumatic rock drill body (5) arranged on the guide rail beam (8) and capable of moving along the guide rail beam (8), wherein a drill rod (16) is inserted into the pneumatic rock drill body (5), and a tail portion of the drill rod (16) is provided with A connecting sleeve (1), a drill rod (12) is installed in the connecting sleeve (1), a fiber pincher (13) is provided on the guide rail crossbeam (8) near the drill bit (14), and the drill rod (12) passes through the fiber pincher (13); the measuring device comprises an axial force measuring module (9) and a torque measuring module (10) provided at the connection between the tail of the drill rod (16) and the connecting sleeve (1), a rotation speed measuring module for detecting the rotation speed of the drill rod (12), and a drilling depth measuring module for detecting the drilling depth; The axial force measurement module (9) comprises a first strain gauge (9-1), a second strain gauge (9-2), a third strain gauge (9-3) and a fourth strain gauge (9-4) which are circumferentially arranged along the connection between the tail of the drill rod (16) and the connecting sleeve (1); the length directions of the first strain gauge (9-1) and the third strain gauge (9-3) are arranged along the axial direction, and the length directions of the second strain gauge (9-2) and the fourth strain gauge (9-4) are arranged perpendicular to the axial direction; the first strain gauge (9-1), the second strain gauge (9-2), the third strain gauge (9-3) and the fourth strain gauge (9-4) are connected to form a first full-bridge measurement circuit; The torque measurement module (10) comprises a fifth strain gauge (10-1) and a sixth strain gauge (10-2) which are circumferentially arranged along the connection between the tail of the drill rod (16) and the connecting sleeve (1); the length directions of the fifth strain gauge (10-1) and the sixth strain gauge (10-2) are arranged along the axial direction; the fifth strain gauge (10-1) and the sixth strain gauge (10-2) are arranged at intervals from the first strain gauge (9-1) and the fourth strain gauge (9-4); and the fifth strain gauge (10-1), the sixth strain gauge (10-2) and two non-inductive resistors are connected to form a second full-bridge measurement circuit.

7. The method for calculating the rock compressive strength according to claim 6, characterized in that: The rotation speed measurement module comprises an L-shaped plate (3) arranged on a pneumatic rock drill body (5), a magnetic steel (2) arranged on the L-shaped plate (3), a collection box (11) bonded to a connecting sleeve (1), and a Hall sensor (6) arranged on a side of the collection box (11) close to the magnetic steel (2); the rotation speed of the drill rod is determined according to the output voltage of the Hall sensor (6); A strain gauge acquisition module is arranged in the acquisition box (11); the first strain gauge (9-1), the second strain gauge (9-2), the third strain gauge (9-3), the fourth strain gauge (9-4), the fifth strain gauge (10-1), and the sixth strain gauge (10-2) are all connected to the strain gauge acquisition module.

8. The method for calculating the rock compressive strength according to claim 7, characterized in that: The drilling depth measurement module is a wire displacement meter (4) arranged on an L-shaped plate (3), the measuring rope end of the wire displacement meter (4) is connected to a fiber pincher (13), and the wire displacement meter (4) is used to measure drilling displacement.

9. The method for calculating rock compressive strength according to claim 8, characterized in that: The wire displacement meter (4) and the strain gauge acquisition module are both connected to a wireless dynamic strain gauge, and the wireless dynamic strain gauge is connected to a computer via a wireless AP module.

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