Method and system for testing technical effect of fracturing pressure relief in directional long drilling area of coal seam roof

Abstract

The invention discloses a method and system for testing the technical effect of fracturing pressure relief of a directional long drilling area of a coal seam roof. The method comprises the steps that S1, before fracturing construction, a drilling stress meter, an anchor cable dynamometer and a roadway surface displacement measuring point are installed; s2, searching monitoring data of a borehole stress meter, an anchor cable dynamometer and surface displacement which are respectively monitored in the regional fracturing pressure relief process of the same mining area, and respectively preprocessing the three kinds of data to respectively obtain variables reflecting fracturing pressure relief effect characteristics; s3, carrying out grade classification on the variables and the data in the step S2, and respectively establishing Bayes discrimination functions according to the variables corresponding to each grade; s4, preprocessing the data measured in the step S1, substituting the obtained variables into a discrimination function, and determining the levels of the variables obtained in the step S1 and the measured data; and S5, the fracturing pressure relief effect is scored according to the grades of all the data measured in the step S1. According to the method, the fracturing pressure relief effect and the influence on the roadway and the like in the pressure relief process can be accurately judged according to the measured data monitored by the borehole stressometer, the anchor cable dynamometer and the roadway surface displacement. And through Bayes function discrimination, evaluation of the fracturing pressure relief technical effect with relatively high accuracy can be obtained.

Description

Technical Field

[0001] The invention relates to the technical field of safe mining of coal mines, and in particular to a method and system for testing the effect of fracturing and pressure relief technology in a directional long-drilling area of ​​a coal seam roof. Background Art

[0002] Directional long-hole regional fracturing technology is an engineering operation technology for regional liquid CO2 phase change fracturing using a complete set of downhole directional long-distance drilling facilities, that is, using a kilometer-long directional drilling rig equipped with wired or wireless measurement while drilling technology. It can provide real-time feedback during drilling, adjust and control the direction of the drill bit to achieve high-precision drilling and long-distance stable drilling, and realize the designed fracturing trajectory. The drilling length is usually more than 300m, and the fracturing range can cover the entire working face area or even wider, which can avoid the shortcomings of conventional hydraulic fracturing in terms of fracturing depth, fracturing layer, and fracturing schedule.

[0003] Directional long-hole regional fracturing technology has great potential for pre-cracking of composite roofs in deep coal seams. This technology can effectively reduce the overall strength of the roof by implementing liquid CO2 phase change fracturing on the composite roof above the mined coal seam, and reduce the strong mine pressure and even rock burst accidents caused by the failure of the roof to collapse in time due to coal mining. However, the evaluation of the fracturing and pressure relief effect of the composite roof of deep coal seams has always been a major problem. At present, it is mainly evaluated by microseismic, acoustic emission and other detection methods, which have shortcomings such as lack of intuitiveness and inability to quantitatively evaluate the fracturing effect, which seriously hinders the development and progress of this technology.

[0004] Therefore, it is urgent to provide a method for testing the effect of fracturing and pressure relief technology in the directional long-hole drilling area of ​​the coal seam roof. Summary of the invention

[0005] In order to solve the above problems, the technical solution of the present invention provides a method and system for testing the effect of fracturing and pressure relief technology in a directional long drilling hole area on the roof of a coal seam, which solves the problem of being unable to quantitatively evaluate the fracturing effect.

[0006] According to a first aspect of the technical solution of the present invention, a method for testing the effect of the fracturing and pressure relief technology in the directional long drilling area of ​​the coal seam roof is provided, comprising:

[0007] S1. Before the fracturing construction, borehole stress gauges are installed in the track tunnel and belt tunnel respectively, and anchor dynamometers are installed in the track tunnel, belt tunnel and mining area tunnel. Displacement measurement points on the tunnel surface are set at the installation positions of the anchor dynamometers, and data monitoring is performed before, during and after the fracturing construction;

[0008] S2. Find the borehole stress gauge, anchor dynamometer and surface displacement monitoring data monitored during the regional fracturing and pressure relief process in the same mining area or mining areas with similar ore rocks and geological conditions, pre-process the three types of data respectively, and obtain variables reflecting the characteristics of the fracturing and pressure relief effect;

[0009] S3, classifying the variables and data in step S2 according to whether the results meet the design goals, marking the data, and establishing Bayesian discriminant functions according to the variables corresponding to each level;

[0010] S4, after the data measured in step S1 are preprocessed in step S2, the obtained variables are respectively introduced into the discriminant function of step S3 to determine the level of the variables obtained in step S1 and the measured data;

[0011] S5. Score the fracturing pressure relief effect according to the level of each data measured in step S1.

[0012] In the above scheme, step S1 includes:

[0013] S11, installing two groups of the borehole stress gauges in the track lane and the belt lane respectively;

[0014] S12, installing the anchor dynamometer at the five measuring stations in the track lane, belt lane and main lane of the mining area;

[0015] S13. Use the cross point method to set up the displacement measuring points on the tunnel surface.

[0016] In the above scheme, the variables reflecting the characteristics of the fracturing pressure relief effect obtained from the three types of data in step S2 include:

[0017] Borehole stress gauge data: stress change amplitude, stress change standard deviation and principal stress direction change angle;

[0018] Anchor cable dynamometer data: tension change amplitude, tension change standard deviation and tension change rate;

[0019] Surface displacement monitoring data: cumulative displacement, displacement change rate and displacement change rate.

[0020] In the above solution, in step S3, classifying the variables into different levels includes:

[0021] If the design target of fracturing pressure relief is effectively achieved, the measured data is Level I;

[0022] If the design target of fracturing pressure relief is not fully achieved but the long-term stability can be maintained, the measured data is Level II;

[0023] If the design target of fracturing pressure relief is not achieved and harm is caused in subsequent engineering practice, the measurement data is Level III.

[0024] In the above scheme, step S3 includes:

[0025] Substitute the data in step S2 into the Bayes discriminant function corresponding to each level for level judgment. If the judgment result is the same as the original judgment level, the judgment is correct. If the judgment result is different from the original judgment level, the judgment is wrong. Calculate the correct judgment rate of the Bayes discriminant function based on the judgment result.

[0026] In the above scheme, step S4 includes:

[0027] The variables are respectively introduced into the discriminant functions of step S3, and the level with the largest discriminant function value is the level where the variables and the measured data are located.

[0028] In the above scheme, establishing the Bayesian discriminant function in step S3 includes:

[0029] Calculate the mean and mean vector of each variable in each level;

[0030] Calculate the covariance matrix between all variables in each level and find its inverse matrix;

[0031] Calculate the prior probabilities of three types of data;

[0032] The Bayesian discriminant function is established according to the mean vector, the inverse matrix and the prior probability.

[0033] In the above scheme, in step S5, the three types of data are scored respectively, and the scores are accumulated.

[0034] According to a second aspect of the technical solution of the present invention, a system for testing the effect of fracturing and pressure relief technology in a directional long drilling area of ​​a coal seam roof is provided. The system is used to implement the method for testing the effect of fracturing and pressure relief technology in a directional long drilling area of ​​a coal seam roof described in any one of the above schemes. The system includes:

[0035] The data acquisition module is used to install borehole stress gauges in the track lane and belt lane respectively before fracturing construction, install anchor dynamometers in the track lane, belt lane and mining area lane, and set the lane surface displacement measurement points at the installation positions of the anchor dynamometers;

[0036] The data processing module is used to find the borehole stress gauge, anchor dynamometer and surface displacement monitoring data monitored during the regional fracturing and pressure relief process in the same mining area or mining areas with similar ore rocks and geological conditions, and pre-process the three types of data to obtain variables reflecting the characteristics of the fracturing and pressure relief effect;

[0037] A function establishment module is used to classify the variables and data in the data processing module according to whether the results meet the design goals, mark the data, and establish Bayesian discriminant functions according to the variables corresponding to each level;

[0038] The level determination module is used to carry out preprocessing of the data measured by the data acquisition module by the data processing module, and then respectively bring the obtained variables into the discriminant function of the function establishment module to determine the level of the variables obtained in the data acquisition module and each measured data;

[0039] The scoring module is used to score the fracturing pressure relief effect according to the level of each data measured in the data acquisition module.

[0040] According to a third aspect of the technical solution of the present invention, there is provided an electronic device, the electronic device comprising:

[0041] A memory storing executable instructions;

[0042] A processor, wherein the processor runs the executable instructions in the memory to implement the method described in any one of the above schemes.

[0043] Beneficial effects of the present invention:

[0044] The present invention discloses a method and system for testing the effect of fracturing and pressure relief technology in the directional long drilling area of ​​the coal seam roof. The data measured by the borehole stress gauge, the anchor dynamometer, and the roadway surface displacement monitoring can more accurately judge the effect of fracturing and pressure relief and the impact on the roadway during the pressure relief process. After preprocessing the data, variables that can characterize the effect of fracturing and pressure relief technology in the directional long drilling area of ​​the coal seam roof are obtained. Through Bayes function discrimination, the evaluation of the effect of fracturing and pressure relief technology with a high accuracy can be obtained.

[0045] The data from borehole stress gauges, anchor dynamometers, and tunnel surface displacement monitoring can more accurately reflect the effect of the directional long-hole fracturing and pressure relief technology in the coal seam roof from multiple dimensions, and form a quantitative indicator to measure the effect of the fracturing and pressure relief technology. This method is more intuitive and objective than traditional qualitative evaluation, and is more suitable for technology comparison and effect optimization; it realizes the fusion analysis of multi-source data, thereby avoiding the limitations of a single monitoring method and enhancing the comprehensiveness and reliability of the evaluation.

[0046] Combined with the Bayesian function discrimination, it has the ability to handle uncertainty and noise, and can reasonably handle possible measurement errors or anomalies in the data through the combination of prior and posterior probabilities. This can improve the robustness of the analysis results and avoid erroneous evaluations caused by single abnormal data. According to specific needs, the prior distribution and model parameters can be adjusted, and it can also be expanded to more monitoring methods or data types. This flexibility enables the method to adapt to different geological conditions or technical scenarios and improve the scope of application of technical applications. Through the comprehensive evaluation method of cumulative scores, it can not only evaluate the technical effect, but also provide a comparison basis for fracturing schemes under different working conditions, help optimize construction parameters and fracturing design, and further improve the effect of technical application. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0048] Figure 1 It is a flow chart of the method for testing the effect of the regional fracturing and pressure relief technology for directional long drilling of coal seam roof disclosed in the present invention;

[0049] Figure 2 It is a schematic diagram of the distribution of measuring stations and installation of monitoring equipment for the method for testing the effect of the regional fracturing and pressure relief technology for directional long drilling holes in the coal seam roof disclosed in the present invention;

[0050] Figure 3 A schematic diagram of the installation of a borehole stress meter for the method for testing the effect of the regional fracturing and pressure relief technology for the directional long-hole drilling of the coal seam roof disclosed in the present invention;

[0051] Figure 4 It is a schematic diagram of the layout of the tunnel surface displacement monitoring section of the method for testing the effect of the regional fracturing and pressure relief technology for directional long drilling holes in the coal seam roof disclosed in the present invention.

[0052] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0053] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0054] The terms "first", "second", etc. in the specification and claims of the present disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein, for example.

[0055] In addition, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such process, method, product, or apparatus.

[0056] Multiple includes two or more.

[0057] It should be understood that the term "and / or" used in this disclosure is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone.

[0058] like Figure 1 to Figure 4 As shown, an embodiment of the technical solution of the present invention provides a method for testing the effect of the fracturing and pressure relief technology in the directional long drilling area of ​​the coal seam roof, comprising:

[0059] S1. Before fracturing construction, install borehole stress gauges in the track tunnel and belt tunnel respectively, install anchor dynamometers in the track tunnel, belt tunnel and mining area tunnel, set up tunnel surface displacement measurement points at the installation positions of anchor dynamometers, and conduct data monitoring before, during and after fracturing construction;

[0060] S2. Find the borehole stress gauge, anchor dynamometer and surface displacement monitoring data monitored during the regional fracturing and pressure relief process in the same mining area or mining areas with similar ore rocks and geological conditions, pre-process the three types of data respectively, and obtain variables reflecting the characteristics of the fracturing and pressure relief effect;

[0061] S3, classify the variables and data in step S2 into levels according to whether the results meet the design goals, mark the data, and establish Bayesian discriminant functions according to the variables corresponding to each level;

[0062] S4, after the data measured in step S1 are preprocessed in step S2, the obtained variables are respectively introduced into the discriminant function of step S3 to determine the level of the variables obtained in step S1 and the measured data;

[0063] S5. Score the fracturing pressure relief effect according to the level of each data measured in step S1.

[0064] Step S1 includes:

[0065] S11. Install two sets of borehole stress gauges in the track lane and belt lane respectively;

[0066] Specifically, the spacing between the two groups of borehole stress gauges in each tunnel is adjusted within the range of 40 to 80 m according to the differences in geological conditions. During installation, one group is installed inward with the stop mining line as the midpoint, and one group is installed outward. At the same time, one group of borehole stress gauges is installed in the main tunnel of the mining area and in the middle of the working face.

[0067] Furthermore, six strain gauges are arranged at each measuring station, with the interval between each strain gauge being 2 to 4 meters, and the installation depth of the borehole strain gauges is flexibly arranged between 3 and 12 meters according to the geological conditions. The borehole diameter is 42 mm, and the borehole is installed horizontally at a distance of 1.2 to 1.5 meters from the tunnel floor.

[0068] S12. Anchor dynamometers are installed at the five measuring stations in the track lane, belt lane and main lane of the mining area;

[0069] Specifically, each measuring station needs to install an anchor cable force monitoring point. The anchor cable needs to be re-laid and arranged between two rows of steel belts, and a flat anchor cable tray needs to be used when installing the anchor cable dynamometer.

[0070] S13. Use the cross-point method to set up displacement measuring points on the tunnel surface.

[0071] Specifically, a 30mm and 400mm deep hole is drilled in the middle of the top and bottom plates in the vertical direction and in the horizontal direction of the two sides, and a 32mm and 400mm long wooden pile is driven into the hole. Curved measuring nails are installed at the ends of the wooden piles on the top plate and the upper side, and flat-head measuring nails are installed at the ends of the wooden piles on the bottom plate and the lower side. The axial spacing of the two monitoring sections along the tunnel is selected between 0.4m and 1.2m according to the geological conditions. The anchor dynamometer can be arranged in combination with the surface displacement measuring points, but if the density of the dynamometer is insufficient, the displacement monitoring section can be arranged independently to avoid monitoring blind spots.

[0072] like Figure 4As shown, the method for observing the surface displacement of the tunnel is: tighten the measuring rope between C and D, tighten the steel ruler between A and B, and measure the AO and AB values; tighten the measuring rope between A and B, tighten the steel ruler between C and D, and measure the CO and CD values; the measurement accuracy is required to reach 1mm, and 0.5mm is estimated.

[0073] The measurement frequency of tunnel surface displacement is: once a day when the mining face is within 100m from the stop mining line, and 1 to 2 times a week at other times.

[0074] In step S1, various data are monitored starting from 1 to 3 days before the fracturing operation and ending when the surrounding rock state meets the design requirements after the operation is completed.

[0075] The variables reflecting the characteristics of the fracturing pressure relief effect obtained from the three types of data in step S2 include:

[0076] Borehole stress gauge data, borehole dynamometers are used to evaluate rock stability and stress distribution; help determine stress redistribution and effective pressure relief range during fracturing.

[0077] Stress change amplitude: maximum stress minus minimum stress; whether the surrounding rock stress can be significantly reduced in the fracturing area can indicate whether the stress is successfully released;

[0078] Stress change standard deviation: After fracturing, if the stress concentration phenomenon is weakened and the stress field tends to be uniform, it means that fracturing plays a role in reducing stress concentration; it is used to characterize the uniformity of stress release;

[0079] The angle of change of the principal stress direction: characterizes the adjustment of the mechanical properties of the rock mass.

[0080] Anchor dynamometer data: Anchor dynamometer is used to evaluate the stability and safety of the support system; determine whether the anchor force exceeds the design range and warn of possible support failure; reflect the impact of surrounding rock deformation on the support system and guide support optimization.

[0081] Tension change range: After fracturing and unloading, if the initial stress and long-term stress of the anchor cable drop significantly, it indicates that the surrounding rock pressure has been released. The maximum tension minus the minimum tension is used to characterize the maximum tension change range.

[0082] Standard deviation of tension change: If the fluctuation of monitoring data decreases, it means that the stress state of surrounding rock tends to be balanced and the fracturing effect is apparent; it can characterize the uniformity of force in the anchoring area;

[0083] Tension change rate: Characterizes the dynamic response of tension adjustment.

[0084] Surface displacement monitoring data: Surface displacement monitoring is used to determine the overall deformation trend of the rock mass; provide warnings of rock deformation during fracturing; and monitor the impact of fracturing activities on rock stability.

[0085] Cumulative displacement: within the same period of time, if the cumulative displacement of the tunnel surface is significantly reduced, it means that the stability of the tunnel is improved after the surrounding rock pressure is released; it can characterize the response intensity of the surface deformation;

[0086] Displacement change rate: If the displacement rate of the tunnel surface decreases significantly, it means that the deformation of the surrounding rock is effectively controlled; it characterizes the dynamic characteristics of surface deformation over time;

[0087] Displacement direction change angle: characterizes the adjustment of surface deformation direction.

[0088] In step S3, classifying the variables into levels includes:

[0089] If the design target of fracturing pressure relief is effectively achieved, the measured data is Level I;

[0090] If the design target of fracturing pressure relief is not fully achieved but the long-term stability can be maintained, the measured data is Level II;

[0091] If the design target of fracturing pressure relief is not achieved and harm is caused in subsequent engineering practice, the measurement data is Level III.

[0092] The establishment of the Bayesian discriminant function in step S3 includes:

[0093] Calculate the mean of each variable in each level, and then get the mean vector μ (g) , μ (g) represents the mean vector of the g-th fracturing pressure relief effect level;

[0094] Calculate the covariance matrix Σ between all variables in each level and find its inverse matrix Σ -1 ;

[0095] With sample frequency q g Represents the prior probability of three levels of data respectively:

[0096]

[0097] Among them, n g is the number of samples from the g-th level of hydraulic fracturing and pressure relief effect in a known classification used to establish the discriminant function in a certain group of samples, and n1+n2+n3=n. n1 is the number of samples of level I, n2 is the number of samples of level II, and n3 is the number of samples of level III.

[0098] The Bayesian discriminant function and criteria for fracturing pressure relief effects of level I, II, and III are established:

[0099]

[0100] In the formula, μ ( ' g) μ(g) The transposed matrix of , y(g / x) is the discriminant function.

[0101] There are three groups of sample data, each of which corresponds to levels I, II, and III of fracturing pressure relief effects, so nine Bayes discriminant functions and discriminant criteria will be obtained.

[0102] All the original samples are respectively brought into the three discriminant functions of each group of data, and each sample is assigned to the level with the largest discriminant function value, and then the correct discrimination rate is calculated; if the judgment result is the same as the original judgment level, the judgment is correct, if the judgment result is different from the original judgment level, the judgment is wrong, and the correct discrimination rate of the Bayes discriminant function is calculated according to the judgment result. The correct discrimination rate is used to quantitatively evaluate the performance of the entire evaluation model, indicating the reliability of the model in multiple tests. If the correct discrimination rate is low, it is necessary to check the quality of the monitoring data, adjust the Bayes discriminant function, optimize the prior probability, etc. When the correct discrimination rate is lower than 90%, the formula needs to be adjusted.

[0103] Step S4 includes:

[0104] The variables are respectively introduced into the discriminant functions of step S3, and discriminant analysis is performed according to the discriminant criteria. The levels of the variables and the measured data are defined as the level with the largest discriminant function value.

[0105] And the posterior probability is calculated according to the following formula to determine the credibility of a group of fracturing unloading effect evaluation.

[0106]

[0107] In the formula, P(g / x) is the posterior probability, and y(i / x) is the calculation result of the three-level discriminant function. If the posterior probability of a certain level is close to 1, it means that the evaluation result is highly reliable. If the posterior probabilities of the three levels are close, the evaluation result is uncertain and needs to be combined with the prior probability to improve the evaluation effect.

[0108] In step S5, the fracturing pressure relief effect is scored according to GB / T50375-2016 construction quality evaluation standard. The three data are scored separately and the scores are accumulated. In a preferred embodiment, the scoring criteria for the fracturing pressure relief effect are shown in Table 1.

[0109] Table 1

[0110]

[0111] According to a second aspect of the technical solution of the present invention, a system for testing the effect of the directional long drilling area fracturing and pressure relief technology in the roof of a coal seam is provided. The system is used to implement the above-mentioned method for testing the effect of the directional long drilling area fracturing and pressure relief technology in the roof of a coal seam. The system includes:

[0112] The data acquisition module is used to install borehole stress gauges in the track lane and belt lane respectively before fracturing construction, install anchor dynamometers in the track lane, belt lane and mining area lane, and set the lane surface displacement measurement points at the installation positions of the anchor dynamometers;

[0113] The data processing module is used to find the borehole stress gauge, anchor dynamometer and surface displacement monitoring data monitored during the regional fracturing and pressure relief process in the same mining area or mining areas with similar ore rocks and geological conditions, and pre-process the three types of data to obtain variables reflecting the characteristics of the fracturing and pressure relief effect;

[0114] The function establishment module is used to classify the variables and data in the data processing module according to whether the results meet the design goals, mark the data, and establish Bayesian discriminant functions according to the variables corresponding to each level;

[0115] The level determination module is used to carry out preprocessing of the data measured by the data acquisition module by the data processing module, and then respectively bring the obtained variables into the discriminant function of the function establishment module to determine the level of the variables obtained in the data acquisition module and the various data measured;

[0116] The scoring module is used to score the fracturing pressure relief effect according to the level of each data measured in the data acquisition module.

[0117] According to a third aspect of the technical solution of the present invention, there is provided an electronic device, the electronic device comprising:

[0118] A memory storing executable instructions;

[0119] A processor runs the executable instructions in the memory to implement any of the methods described above.

[0120] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0121] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0122] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0123] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A method for testing the effect of regional fracturing and pressure relief technology in a directional long-hole drilling area on a coal seam roof, characterized in that: include: S1. Before the fracturing construction, borehole stress gauges are installed in the track tunnel and belt tunnel respectively, and anchor dynamometers are installed in the track tunnel, belt tunnel and mining area tunnel. Displacement measurement points on the tunnel surface are set at the installation positions of the anchor dynamometers, and data monitoring is performed before, during and after the fracturing construction; S2. Find the borehole stress gauge, anchor dynamometer and surface displacement monitoring data monitored during the regional fracturing and pressure relief process in the same mining area or mining areas with similar ore rocks and geological conditions, pre-process the three types of data respectively, and obtain variables reflecting the characteristics of the fracturing and pressure relief effect; S3, classifying the variables and data in step S2 according to whether the results meet the design goals, marking the data, and establishing Bayesian discriminant functions according to the variables corresponding to each level; S4, after the data measured in step S1 are preprocessed in step S2, the variables obtained in step S1 are respectively introduced into the discriminant function of step S3 to determine the level of the variables obtained in step S1 and each measured data; S5. Score the fracturing pressure relief effect according to the level of each data measured in step S1.

2. The method for testing the effect of regional fracturing and pressure relief technology in directional long drilling of coal seam roof according to claim 1 is characterized in that: Step S1 includes: S11, installing two groups of the borehole stress gauges in the track lane and the belt lane respectively; S12, installing the anchor dynamometer at the five measuring stations in the track lane, belt lane and main lane of the mining area; S13. Use the cross point method to set up the displacement measuring points on the tunnel surface.

3. The method for testing the effect of regional fracturing and pressure relief technology in directional long drilling of coal seam roof according to claim 1 is characterized in that: The variables reflecting the characteristics of the fracturing pressure relief effect obtained from the three types of data in step S2 include: Borehole stress gauge data: stress change amplitude, stress change standard deviation and principal stress direction change angle; Anchor cable dynamometer data: tension change amplitude, tension change standard deviation and tension change rate; Surface displacement monitoring data: cumulative displacement, displacement change rate and displacement change rate.

4. The method for testing the effect of regional fracturing and pressure relief technology in directional long drilling of coal seam roof according to claim 1 is characterized in that: In step S3, classifying the variables into different levels includes: If the design target of fracturing pressure relief is effectively achieved, the measured data is Level I; If the design target of fracturing pressure relief is not fully achieved but the long-term stability can be maintained, the measured data is Level II; If the design target of fracturing pressure relief is not achieved and harm is caused in subsequent engineering practice, the measurement data is Level III.

5. The method for testing the effect of regional fracturing and pressure relief technology in directional long drilling of coal seam roof according to claim 1 is characterized in that: Step S3 includes: Substitute the data in step S2 into the Bayes discriminant function corresponding to each level for level judgment. If the judgment result is the same as the original judgment level, the judgment is correct. If the judgment result is different from the original judgment level, the judgment is wrong. Calculate the correct judgment rate of the Bayes discriminant function based on the judgment result.

6. The method for testing the effect of regional fracturing and pressure relief technology in directional long drilling of coal seam roof according to claim 1 is characterized in that: Step S4 includes: The variables are respectively introduced into the discriminant functions of step S3, and the level with the largest discriminant function value is the level where the variables and the measured data are located.

7. The method for testing the effect of regional fracturing and pressure relief technology in directional long drilling of coal seam roof according to claim 1 is characterized in that: The establishment of the Bayesian discriminant function in step S3 includes: Calculate the mean and mean vector of each variable in each level; Calculate the covariance matrix between all variables in each level and find its inverse matrix; Calculate the prior probabilities of three types of data; The Bayesian discriminant function is established according to the mean vector, the inverse matrix and the prior probability.

8. The method for testing the effect of regional fracturing and pressure relief technology in directional long drilling of coal seam roof according to claim 1 is characterized in that: In step S5, the three types of data are scored respectively, and the scores are accumulated.

9. A system for testing the effect of fracturing and pressure relief technology in the directional long-hole drilling area of ​​the coal seam roof, characterized in that: The system is used to implement the method for testing the effect of the regional fracturing and pressure relief technology of the directional long drilling hole in the coal seam roof according to any one of claims 1 to 8, and the system comprises: The data acquisition module is used to install borehole stress gauges in the track lane and belt lane respectively before fracturing construction, install anchor dynamometers in the track lane, belt lane and mining area lane, and set the lane surface displacement measurement points at the installation positions of the anchor dynamometers; The data processing module is used to find the borehole stress gauge, anchor dynamometer and surface displacement monitoring data monitored during the regional fracturing and pressure relief process in the same mining area or mining areas with similar ore rocks and geological conditions, and pre-process the three types of data to obtain variables reflecting the characteristics of the fracturing and pressure relief effect; A function establishment module is used to classify the variables and data in the data processing module according to whether the results meet the design goals, mark the data, and establish Bayesian discriminant functions according to the variables corresponding to each level; The level determination module is used to carry out preprocessing of the data measured by the data acquisition module by the data processing module, and then respectively bring the obtained variables into the discriminant function of the function establishment module to determine the level of the variables obtained in the data acquisition module and each measured data; The scoring module is used to score the fracturing pressure relief effect according to the level of each data measured in the data acquisition module.

10. An electronic device, characterized in that: The electronic device comprises: A memory storing executable instructions; A processor, wherein the processor runs the executable instructions in the memory to implement the method according to any one of claims 1 to 8.

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