A test comparison system and method for monitoring waveforms

Abstract

A kind of test contrast system and method for monitoring waveform, by installing two different types of test probes in the same test environment, ensure that the bottom of two probes is located at the same height, carry out the vibration wave contrast test of active excitation source in ground machine room, and record test waveform, after determining that the waveform recorded by test probe one and test probe two is consistent, take to the downhole installation and carry out test, through shooting operation to excite waveform, for comparing the recorded waveform of two probes, according to the requirement of probe quantity, reasonably select the explosive quantity and shooting position, excite vibration wave through blasting, record the waveform recorded by two probes under the same seismic source, carry out contrast analysis, and according to the analysis result, make corresponding processing, exclude the problems such as probe failure, measuring point position failure, poor waveform propagation path etc. in the process of microseismic signal monitoring, obviously improve the monitoring effect of signal waveform, improve the accuracy of signal monitoring, better guarantee the safety of coal production.

Description

Technical Field

[0001] This invention relates to a test comparison system and method for monitoring waveforms, belonging to the field of coal mine safety technology. Background Technology

[0002] The geological conditions of coal deposits are extremely complex. As coal mining depths increase and the degree of mining deepens, how to mine more safely and efficiently has become an important issue in coal production. Among these issues, rockburst, a significant factor affecting coal mine safety, is an impact dynamic phenomenon in which the elastic energy accumulated in the coal and rock mass is suddenly released into the surrounding space. To achieve the goal of safe production, it is necessary to monitor and control the safety factors that exist during production activities, such as roof delamination and the stress state of the surrounding rock mass.

[0003] Currently, the main methods for monitoring mine pressure used in engineering include microseismic monitoring, acoustic emission, online stress monitoring, and drill cuttings analysis. Among these, microseismic monitoring technology is a geophysical method that uses microseismic signals generated during the loading and fracturing process of coal and rock to study and evaluate the stability of coal and rock masses. Its advantages lie in its ability to monitor mine safety in real-time, continuously, and over a large area, greatly ensuring the safety of coal production activities. However, microseismic monitoring technology still faces many problems in terms of source location accuracy and the accuracy of microseismic wave signal arrival time pickup, significantly affecting the monitoring and control effectiveness. Analysis shows that the monitoring effect of microseismic signals is affected by various factors, such as the received input waveform, the analysis and processing of the input signal, and the type of vibration source. In microseismic monitoring technology, velocity sensors, such as SOS probes and Aramis probes, are often used to receive monitoring waveform signals. Different types of signal probes have different detection accuracy and range. When different signal monitoring systems are installed at adjacent measuring points, the measured amplitudes differ significantly. The reasons for these differences include probe inherent problems, the influence of measuring point location, and propagation paths. Summary of the Invention

[0004] This invention provides a test comparison system and method for monitoring waveforms. This test comparison system and method can compare the signal monitoring effects of different types of probes in mines, thereby eliminating adverse factors affecting the microseismic monitoring effect, improving the accuracy and precision of microseismic monitoring, and ensuring the safety of coal mine production.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: a test comparison system for monitoring waveforms, comprising two different types of test probe one and test probe two, wherein test probe one and test probe two are installed in the same test environment and their output terminals are connected to a waveform signal receiving device.

[0006] Furthermore, it also includes a mounting bracket, which is Y-shaped and includes an upper branch and a lower support. Test probe one and test probe two are respectively fixedly installed at the top of the branch. The top of the branch is embedded with a threaded section that matches the outer circumferential thread of the probe. The support is used to fix the mounting bracket at the test location. The support is an anchor rod.

[0007] Furthermore, the test probe one and test probe two are different types of speed sensors, and their connections to the top of the branch are both threaded connections. The bottoms of test probe one and test probe two are located on the same horizontal line. The distance between the outer circumferences of test probe one and test probe two is 50mm to 100mm. The distance between test probe one and test probe two and the upper end of the support is the same, and this distance is greater than the thread pitch of test probe one and test probe two when screwed into the top of the branch.

[0008] A test comparison method for monitoring waveforms includes the following steps:

[0009] Step 1: Obtain two different types of probes for testing and label them accordingly. One is designated as Test Probe 1 and the other as Test Probe 2. Measure the dimensions of Test Probe 1 and Test Probe 2, including the diameter of the probes and the preset thread pitch for screwing into the mounting bracket.

[0010] Step 2: Place the lower support section of the mounting bracket into cement for curing. Before testing, screw test probe 1 and test probe 2 into the upper part of the branch of the mounting bracket as required, and place the two probes in the same testing environment.

[0011] Step 3: Conduct a vibration wave comparison test of the active excitation source in the ground equipment room and record the test waveform. After confirming that the waveforms recorded by test probe 1 and test probe 2 are consistent, take it downhole for installation and testing.

[0012] Step 4: Based on the probe measurement requirements, reasonably select the amount of explosive and the blasting location. Excite the vibration wave through blasting, record the waveforms recorded by test probe 1 and test probe 2 under the same vibration source, compare and analyze them, and take appropriate actions based on the analysis results.

[0013] Further, in step two, the axial distance between test probe one and test probe two is A, where A = radius of test probe one + radius of test probe two + 50mm to 100mm; the distances between test probe one and test probe two and the upper end of the support are B1 and B2, respectively, and B1 = B2, with a value range of 150mm to 200mm. At the same time, B1 and B2 are greater than the thread pitch of test probe one and test probe two when screwed into the top of the branch; the length of the lower support of the mounting bracket is C, with a value range of 300mm to 500mm.

[0014] Furthermore, in step three, the active excitation source is either stomping or hammering; during underground testing, both test probe one and test probe two are installed on the roadway floor; when the floor is rock, the support is drilled directly, and then test probe one and test probe two are connected to the upper end of the exposed branch; if the floor is coal, cement is poured first, and the diameter N of the hole for placing the mounting bracket is larger than the diameter Ф of the support, at least twice the diameter of the support to achieve a good fixing effect, with a hole depth range of 800mm to 1300mm; after the mounting bracket is fully inserted, the height exposed above the ground ranges from 150mm to 250mm, and after the mounting bracket is vertically placed in place, it is fixed by pouring cement.

[0015] Furthermore, in step four, according to the measurement requirements of test probe one and test probe two, when blasting in the coal seam, the amount of explosive should not be less than 3 kg, and the distance should not be greater than 500 m; the waveforms recorded by test probe one and test probe two under the same seismic source are compared and analyzed, and corresponding processing is carried out based on the analysis results. The specific method is to determine the waveform similarity by calculating the difference ratio of the absolute average values ​​of the two waveform signals. The calculation formula is as follows:

[0016]

[0017] In the formula, X is the amplitude of the waveform signal received by test probe one, Y is the amplitude of the waveform signal received by test probe two, and n is the number of sampling points for waveform comparison calculation. When ADR < 0.2, it indicates that the signals received by test probe one and test probe two have good consistency, the test passes, and it can be used normally. When 0.2 ≤ ADR < 2, it indicates that the signal difference between test probe one and test probe two is small, but there are problems with poor waveform propagation path and unsuitable measurement point position. The measurement points should be adjusted in time. When ADR ≥ 2, it indicates that the signal difference between test probe one and test probe two is large, which is judged as a probe failure problem. The consistency test fails, and the probe should be checked and replaced.

[0018] This invention involves installing two different types of test probes in the same testing environment, ensuring that the bottoms of both probes are at the same horizontal level. First, a comparative test of the vibration waves from an active excitation source is conducted in a surface equipment room, and the test waveforms are recorded. After confirming that the waveforms recorded by test probe one and test probe two are consistent, the probes are then installed underground for testing. Waveforms are generated through blasting operations and compared with the recorded waveforms of the two probes. Based on the probe measurement requirements, the amount of explosive and the blasting location are appropriately selected to generate vibration waves through blasting. The waveforms recorded by test probe one and test probe two under the same seismic source are recorded, compared, and analyzed. Based on the analysis results, corresponding processing is performed to eliminate problems such as probe failure, measurement point ineffectiveness, and poor waveform propagation paths that may occur during microseismic signal monitoring. This significantly improves the monitoring effect of the signal waveform, enhances the accuracy of signal monitoring, and better ensures the safety of coal mine production. The operating principle of this invention is simple and highly reliable. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the test comparison system structure of the present invention;

[0020] Figure 2 This is a flowchart of the testing and comparison method of the present invention.

[0021] In the diagram: 1. Test probe one, 2. Test probe two, 3. Mounting bracket, 4. Branch, 5. Support, 6. Cement. Detailed Implementation

[0022] The invention will now be further described with reference to the accompanying drawings.

[0023] like Figure 1 As shown, a test comparison system for monitoring waveforms includes two different types of test probes, 1 and 2, which are installed in the same test environment and whose outputs are connected to a waveform signal receiving device.

[0024] To facilitate the installation and fixation of test probe 1 and test probe 2, a mounting bracket 3 is also included. The mounting bracket 3 is Y-shaped and includes an upper branch 4 and a lower support 5. Test probe 1 and test probe 2 are respectively fixedly installed at the top of the branch 4, and the support 5 is used to fix the mounting bracket 3 at the test location.

[0025] To ensure the accuracy of the test, the test probe 1 and test probe 2 are different types of velocity sensors, specifically SOS and ARAMI micro-vibration probes. Both are connected to the top of the branch 4 by threads. The bottoms of test probe 1 and test probe 2 are on the same horizontal line. The distance between the outer circumferences of test probe 1 and test probe 2 is 50mm to 100mm. The distance between test probe 1 and test probe 2 and the upper end of the support 5 is the same, and this distance is greater than the thread pitch of test probe 1 and test probe 2 when screwed into the top of the branch 4.

[0026] like Figure 2 As shown, a test comparison method for monitoring waveforms includes the following steps:

[0027] Step 1: Obtain two different types of probes for testing and label them accordingly. One is designated as Test Probe 1 and the other as Test Probe 2. Measure the dimensions of Test Probe 1 and Test Probe 2, including the diameter of the probes and the preset thread pitch for screwing into the mounting bracket 3.

[0028] Step 2: Place the lower support part 5 of the mounting bracket 3 into cement for curing. Before testing, screw the test probe 1 and test probe 2 into the upper end of the branch part 4 of the mounting bracket 3 as required, and place the two probes in the same test environment.

[0029] Step 3: Conduct a vibration wave comparison test of the active excitation source in the ground equipment room and record the test waveform. After confirming that the waveforms recorded by test probe 1 and test probe 2 are consistent, take it downhole for installation and testing.

[0030] Step 4: Based on the probe measurement requirements, reasonably select the amount of explosive and the blasting location. Excite the vibration wave through blasting, record the waveforms recorded by test probe 1 and test probe 2 under the same vibration source, compare and analyze them, and take appropriate actions based on the analysis results.

[0031] To further ensure the accuracy of the test, in step two, the axial distance between test probe 1 and test probe 2 is A, where A = radius of test probe 1 + radius of test probe 2 + 50mm to 100mm; the distances between test probe 1 and test probe 2 and the upper end of the support 5 are B1 and B2, respectively, with B1 = B2, and the value range is 150mm to 200mm. At the same time, B1 and B2 are greater than the thread pitch of test probe 1 and test probe 2 when screwed into the top of the branch 4; the length of the lower support 5 of the mounting bracket 3 is C, and the value range of C is 300mm to 500mm.

[0032] As a preferred method, in step three, the active excitation source is either stomping or hammering. During underground testing, test probe 1 and test probe 2 are both installed on the roadway floor. When the floor is rock, the support 5 is drilled directly, and test probe 1 and test probe 2 are connected to the upper end of the branch 4 exposed on the ground. If the floor is coal, cement is poured first, and the diameter N of the borehole for placing the mounting bracket 3 is greater than the diameter Ф of the support 5, at least twice the diameter of the support 5 to achieve a good fixing effect. The borehole depth ranges from 800mm to 1300mm. After the mounting bracket 3 is fully inserted, the height exposed on the ground ranges from 150mm to 250mm. After the mounting bracket 3 is placed vertically in place, it is fixed by pouring cement. The solidified cement 6 is cylindrical to ensure good stability of the entire device when placed on a flat surface. The preferred dimensions are height D = 200mm and diameter E = 300mm.

[0033] As a preferred method, in step four, according to the measurement requirements of test probe 1 and test probe 2, when blasting in the coal seam, the amount of explosive should not be less than 3 kg and the distance should not be greater than 500 m; the waveforms recorded by test probe 1 and test probe 2 under the same seismic source are compared and analyzed, and corresponding processing is carried out based on the analysis results. The specific method is to determine the waveform similarity by calculating the difference ratio of the absolute average values ​​of the two waveform signals. The calculation formula is as follows:

[0034]

[0035] In the formula, X is the amplitude of the waveform signal received by test probe 1, Y is the amplitude of the waveform signal received by test probe 2, and n is the number of sampling points for waveform comparison calculation, which is selected according to the specific characteristics of the waveform. By default, 1000 sampling points are selected before and after the signal peak, and n = 2000.

[0036] When ADR < 0.2, it indicates that the signals received by test probe 1 and test probe 2 have good consistency, the test is passed, and they can be used normally. When 0.2 ≤ ADR < 2, it indicates that the signal difference between test probe 1 and test probe 2 is small, but there are problems with poor waveform propagation path and unsuitable measurement point position. The measurement point should be adjusted in time. When ADR ≥ 2, it indicates that the signal difference between test probe 1 and test probe 2 is large, which is judged as a probe failure problem. The consistency test fails, and the probe should be checked and replaced.

Claims

1. A test comparison system for monitoring waveforms, characterized in that, It includes two different types of test probes, one (1) and two (2), which are installed in the same test environment and whose outputs are connected to a waveform signal receiving device; It also includes a mounting bracket (3), which is Y-shaped and includes an upper branch (4) and a lower support (5); test probe one (1) and test probe two (2) are respectively fixedly installed at the top of the branch (4), and the support (5) is used to fix the mounting bracket (3) at the test location; The test probe one (1) and test probe two (2) are different types of speed sensors. The connection between them and the top of the branch (4) is a threaded connection. The bottoms of the test probe one (1) and test probe two (2) are on the same horizontal line. The distance between the outer circumferences of the test probe one (1) and test probe two (2) is 50 mm to 100 mm. The distance between the test probe one (1) and test probe two (2) and the upper end of the support (5) is the same, and this distance is greater than the thread pitch of the test probe one (1) and test probe two (2) screwed into the top of the branch (4).

2. A test comparison method based on the test comparison system for monitoring waveforms as described in claim 1, characterized in that, Includes the following steps: Step 1: Obtain two different types of probes for testing and label them. One is labeled as Test Probe 1 (1) and the other as Test Probe 2 (2). Measure the dimensions of Test Probe 1 (1) and Test Probe 2 (2), including the diameter of the probes and the thread pitch of the preset mounting bracket (3). Step 2: Place the lower support part (5) of the mounting bracket (3) into cement for curing. Before testing, screw the test probe 1 (1) and test probe 2 (2) into the upper end of the branch part (4) of the mounting bracket (3) as required, and put the two probes in the same test environment. Step 3: Conduct a vibration wave comparison test of the active excitation source in the ground equipment room and record the test waveform. After confirming that the waveforms recorded by test probe 1 (1) and test probe 2 (2) are consistent, take it down into the well for testing. Step 4: Based on the probe measurement requirements, reasonably select the amount of explosive and the blasting location. Through the blasting to generate shock waves, record the waveforms recorded by test probe one (1) and test probe two (2) under the same source, conduct comparative analysis, and make corresponding processing based on the analysis results. In step four, according to the measurement requirements of test probe one (1) and test probe two (2), when blasting in the coal seam, the amount of explosive should not be less than 3 kg and the distance should not be greater than 500 m; the waveforms recorded by test probe one (1) and test probe two (2) under the same seismic source are compared and analyzed, and the specific method for processing according to the analysis results is to judge the waveform similarity by calculating the difference ratio of the absolute average values ​​of the two waveform signals. The calculation formula is as follows: ； In the formula, X is the amplitude of the waveform signal received by test probe one (1), Y is the amplitude of the waveform signal received by test probe two (2), and n is the number of sampling points for waveform comparison calculation. When ADR < 0.2, it means that the signals received by test probe one (1) and test probe two (2) have good consistency, the test is passed, and it can be used normally. When 0.2≤ADR<2, it means that the signal difference between test probe one (1) and test probe two (2) is small, but there are problems with poor waveform propagation path and unsuitable measurement point position. The measurement point should be adjusted in time. When ADR≥2, it means that the signal difference between test probe one (1) and test probe two (2) is large, which is judged as a probe failure problem. The consistency test fails, and the probe should be checked and replaced.

3. The test comparison method for monitoring waveforms according to claim 2, characterized in that, In step two, the axial spacing between test probe one (1) and test probe two (2) is A, where A = radius of test probe one (1) + radius of test probe two (2) + 50mm to 100mm; the distances between test probe one (1) and test probe two (2) and the upper end of the support part (5) are B1 and B2, respectively, and B1 = B2, with a value range of 150mm to 200mm. At the same time, B1 and B2 are greater than the thread pitch of test probe one (1) and test probe two (2) screwed into the top of the branch part (4); the length of the lower support part (5) of the mounting bracket (3) is C, with a value range of 300mm to 500mm.

4. The test comparison method for monitoring waveforms according to claim 2, characterized in that, In step three, the active excitation source is either stomping or hammering. During the underground test, test probe one (1) and test probe two (2) are both installed on the roadway floor. When the floor is a rock stratum, the support part (5) is drilled directly, and test probe one (1) and test probe two (2) are connected to the upper end of the branch part (4) exposed on the ground. If the floor is coal, cement is poured first, and the diameter N of the hole for placing the mounting bracket (3) is greater than the diameter Ф of the support part (5), at least twice the diameter of the support part (5) to achieve a good fixing effect. The hole depth range is 800 mm to 1300 mm. After the mounting bracket (3) is fully inserted, the height exposed on the ground ranges from 150 mm to 250 mm. After the mounting bracket (3) is placed vertically in place, it is fixed by pouring cement.

Images