Comprehensive evaluation test method and device for dynamic instability characteristics of coal and rock

Abstract

The present invention proposes a comprehensive evaluation test method and device for the dynamic instability characteristics of coal rock, which obtains coal rock samples; based on the uniaxial compressive strength of the coal rock samples, controls the uniaxial loading of the coal rock samples at different loading rates to obtain stress-strain relationship curves of the first and second stages before failure of the coal rock samples; calculates the first accumulated elastic energy and the first dissipated energy of the first stage, and the second accumulated elastic energy, the second dissipated energy and the post-peak loss energy of the second stage according to the stress-strain relationship curve; and then calculates the total residual release energy of the coal rock sample; and based on the equivalent dynamic failure time converted from the total residual release energy and the failure time, calculates the release rate of the total residual release energy to evaluate the dynamic instability characteristics of the coal rock. Therefore, by introducing uniaxial compressive strength, yield deviation, accumulated elastic energy and equivalent dynamic failure time, the release rate of the total residual release energy is calculated, thereby improving the accuracy and precision of evaluating the dynamic instability of the coal rock.

Description

Technical Field

[0001] The present invention relates to the field of coal mine safety technology, and in particular to a method and device for comprehensively evaluating and testing dynamic instability characteristics of coal and rock. Background Art

[0002] With the increasing consumption of coal resources and mining intensity, the mining value of high-quality coal resources in the impact ground pressure coal seams, which account for a considerable proportion of reserves, is huge. However, mine rock dynamic disasters seriously threaten the safe, efficient and intelligent mining of mines, and the issue of safe mining is becoming increasingly prominent.

[0003] In related technologies, methods for evaluating the dynamic instability characteristics of coal and rock are generally represented by uniaxial compressive strength, elastic energy index, impact energy index, and dynamic failure time. The dynamic failure characteristics of coal and rock during failure are obtained by applying a comprehensive fuzzy evaluation method based on the test results of multiple samples and multiple indicators, or by considering a single indicator such as energy, deformation or strength to evaluate the dynamic instability characteristics of coal and rock. However, the above methods require multiple sample tests to obtain the results of a multi-indicator fuzzy comprehensive evaluation of the dynamic instability characteristics of coal and rock, and use a fuzzy comprehensive judgment method to evaluate the dynamic instability characteristics of coal and rock. The testing procedure is very complicated, consumes high manpower and financial resources, and the factors considered in the single indicator evaluation are not comprehensive and specific. Therefore, a more reliable comprehensive evaluation test method for the dynamic instability characteristics of coal and rock is urgently needed. Summary of the Invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, the first purpose of the present invention is to propose a comprehensive evaluation test method for the dynamic instability characteristics of coal and rock. By introducing uniaxial compressive strength, yield deviation, accumulated elastic energy and equivalent dynamic failure time, the release rate of the total residual released energy is calculated to improve the accuracy and precision of the evaluation of the dynamic instability of coal and rock.

[0006] The second purpose of the present invention is to provide a comprehensive evaluation and testing device for the dynamic instability characteristics of coal and rock.

[0007] A third object of the present invention is to provide an electronic device.

[0008] A fourth object of the present invention is to provide a non-transitory computer-readable storage medium storing computer instructions.

[0009] To achieve the above objectives, the first embodiment of the present invention provides a comprehensive evaluation and testing method for coal and rock dynamic instability characteristics, comprising:

[0010] Obtain coal rock samples;

[0011] Based on the average uniaxial compressive strength of the coal rock sample, a stress-strain relationship curve is established when the coal rock sample is loaded at different loading rates in the first and second stages within the failure time of the coal rock sample;

[0012] Calculating the first dissipated energy and the first accumulated elastic energy input in the first stage, and the second accumulated elastic energy, the second dissipated energy, and the post-peak loss energy input in the second stage according to the target uniaxial compressive strength, failure time, and yield deviation of the coal rock sample in the stress-strain relationship curve;

[0013] Calculating the total residual released energy within the destruction time of the coal rock sample based on the first dissipated energy, the first accumulated elastic energy, the second dissipated energy, the second accumulated elastic energy and the post-peak loss energy, the target uniaxial compressive strength, and the yield deviation;

[0014] Based on the loading rate, converting the failure time into an equivalent dynamic failure time for the coal rock sample to be destroyed;

[0015] According to the total residual released energy and the equivalent dynamic failure time, the release rate of the total residual released energy is calculated to evaluate the dynamic instability characteristics of coal and rock.

[0016] To achieve the above-mentioned purpose, the second embodiment of the present invention provides a comprehensive evaluation and testing device for coal and rock dynamic instability characteristics, comprising:

[0017] A first acquisition module is used to obtain coal and rock samples;

[0018] A construction module is used to establish, based on the average uniaxial compressive strength of the coal rock sample, a stress-strain relationship curve when the coal rock sample is loaded at different loading rates in the first stage and the second stage within the failure time of the coal rock sample;

[0019] a first calculation module, configured to calculate the first dissipated energy and the first accumulated elastic energy input in the first stage, and the second accumulated elastic energy, the second dissipated energy, and the post-peak loss energy input in the second stage, based on the target uniaxial compressive strength, the failure time, and the yield deviation of the coal rock sample in the stress-strain relationship curve;

[0020] a second calculation module, configured to calculate the total residual released energy within the destruction time of the coal rock sample based on the first dissipated energy, the first accumulated elastic energy, the second dissipated energy, the second accumulated elastic energy and the post-peak loss energy, the target uniaxial compressive strength, and the yield deviation;

[0021] a conversion module, configured to convert the failure time into an equivalent dynamic failure time of the coal rock sample based on the loading rate;

[0022] The third calculation module is used to calculate the release rate of the total residual released energy based on the total residual released energy and the equivalent dynamic failure time, so as to evaluate the dynamic instability characteristics of coal and rock.

[0023] To achieve the above-mentioned purpose, the third aspect embodiment of the present invention proposes an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the method described in the first aspect.

[0024] In order to achieve the above-mentioned objectives, an embodiment of the fourth aspect of the present invention proposes a non-transitory computer-readable storage medium storing computer instructions, where the computer instructions are used to enable the computer to execute the method described in the first aspect.

[0025] The comprehensive evaluation test method, device electronic equipment and storage medium of the coal rock dynamic instability characteristics of the embodiment of the present invention obtain coal rock samples; based on the uniaxial compressive strength of the coal rock samples, the uniaxial loading of the coal rock samples is controlled at different loading rates to obtain the stress-strain relationship curves of the first and second stages before the destruction of the coal rock samples; the first accumulated elastic energy and the first dissipated energy of the first stage, and the second accumulated elastic energy, the second dissipated energy and the post-peak loss energy of the second stage are calculated according to the stress-strain relationship curves; the total residual release energy of the coal rock sample is then calculated; and based on the equivalent dynamic destruction time converted from the total residual release energy and the destruction time, the release rate of the total residual release energy is calculated to evaluate the dynamic instability characteristics of the coal rock. Therefore, by introducing uniaxial compressive strength, yield deviation, accumulated elastic energy and equivalent dynamic destruction time, the release rate of the total residual release energy is calculated, thereby improving the accuracy and precision of evaluating the dynamic instability of the coal rock.

[0026] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0028] Figure 1 A schematic flow chart of a comprehensive evaluation test method for coal rock dynamic instability characteristics provided by an embodiment of the present invention;

[0029] Figure 2 A stress-strain curve diagram provided by an embodiment of the present invention;

[0030] Figure 3A schematic flow chart of another method for comprehensive evaluation and testing of coal and rock dynamic instability characteristics provided by an embodiment of the present invention;

[0031] Figure 4 A schematic structural diagram of a comprehensive evaluation and testing device for dynamic instability characteristics of coal and rock provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0033] It should be noted that the acquisition, storage, use, and processing of data in the technical solution of the present invention comply with the relevant provisions of national laws and regulations.

[0034] The following describes a method and apparatus for comprehensive evaluation of dynamic instability characteristics of coal and rock according to an embodiment of the present invention with reference to the accompanying drawings.

[0035] Figure 1 A schematic flow chart of a comprehensive evaluation test method for coal rock dynamic instability characteristics provided by an embodiment of the present invention.

[0036] like Figure 1 As shown, the method includes the following steps:

[0037] Step 101: Obtain coal rock samples.

[0038] In some embodiments, an implementation method for obtaining coal rock samples may be: collecting multiple initial coal rock samples with coal rock characteristics, wherein the height orientation of the coal rock in the initial coal rock sample should be perpendicular to the bedding plane of the coal, and the coal rock has no obvious cracks; performing standardized sample processing on the initial coal rock sample to obtain a coal rock sample whose unevenness is smaller than a preset size and whose axial deviation is smaller than a preset angle.

[0039] Specifically, according to the sampling rules for coal rock mechanical property testing, multiple representative sampling point groups are selected based on the changes in the characteristics of the coal rock itself to ensure that the height orientation of the coal samples in the initial coal rock samples should be perpendicular to the coal bedding plane, and the coal samples should not have obvious cracks. After the initial coal rock samples are sampled, they are wrapped in multiple layers of plastic film and transported to a designated location by hand or by special vehicle. They are placed in sampling boxes and filled with materials such as sawdust and foam, and then transported to the laboratory for further processing. A standard core drill is used to drill a cylindrical sample with a diameter of 50 mm from the initial coal rock sample. The sample is then clamped in a sample cutter and cut into a standard initial coal rock sample with a height of 100 mm. The two end faces of the standard initial coal rock sample are polished to make the unevenness of the standard initial coal rock sample less than 0.05 mm and the axial deviation less than 0.25°, thereby obtaining an accurate coal rock sample.

[0040] Step 102 , based on the average uniaxial compressive strength of the coal rock sample, establish a stress-strain relationship curve when the coal rock sample is loaded at different loading rates in the first and second stages within the failure time of the coal rock sample.

[0041] Optionally, the average uniaxial compressive strength can be determined based on the experimental results of historical coal and rock samples, or measured according to the physical and mechanical properties of coal and rock, or tested by uniaxial compressive strength measurement and softening coefficient calculation methods, but is not limited to this and this embodiment does not make specific limitations on this.

[0042] In some embodiments, based on the uniaxial compressive strength of the coal rock sample, an implementation method of the stress-strain relationship curve when the coal rock sample is loaded at different loading rates in the first and second stages can be as follows: based on the average uniaxial compressive strength of the coal rock sample, the loading rate controlled by the first preset stress is loaded to a preset percentage of the average uniaxial compressive strength, and the stress is unloaded to the second preset stress after stopping loading as the first stage; after unloading the stress to the second preset stress, the coal rock sample is loaded to a destroyed state at a loading rate controlled by strain at a preset time interval as the second stage; and within the destruction time of the coal rock sample, a stress-strain relationship curve between the target uniaxial compressive strength (strain) and stress energy (stress) of the coal rock sample corresponding to the first and second stages is established.

[0043] Optionally, after the appearance size and physical parameters of the coal rock sample are qualified, it is placed between the two loading plates of the press, first loaded to 75% of the uniaxial compressive strength at a stress-controlled loading rate of 0.5 MPa / s, then unloaded to 0.2 MPa after stopping loading, and then -6 The coal sample was loaded at a strain-controlled loading rate of 1 / s until it completely failed, and the stress-strain characteristics of the coal sample were recorded during the process. Figure 2In addition, the above test can be repeated on three coal and rock samples from the same group to improve reliability.

[0044] Step 103, based on the target uniaxial compressive strength, failure time, and yield deviation of the coal rock sample in the stress-strain relationship curve, calculate the first dissipated energy and first accumulated elastic energy input in the first stage, as well as the second accumulated elastic energy, second dissipated energy, and post-peak loss energy input in the second stage.

[0045] In some embodiments, the first dissipated energy and the first accumulated elastic energy input in the first stage, and the second accumulated elastic energy, the second dissipated energy and the post-peak loss energy input in the second stage are calculated according to the target uniaxial compressive strength, failure time and yield deviation of the coal rock sample in the stress-strain relationship curve. One implementation method can be to calculate the first dissipated energy and the first accumulated elastic energy input in the first stage according to the target uniaxial compressive strength, failure time and yield deviation of the coal rock sample in the stress-strain relationship curve; and calculate the second dissipated energy and the second accumulated elastic energy based on the first dissipated energy, the target uniaxial compressive strength, the yield deviation and the first accumulated elastic energy.

[0046] Furthermore, in the stress-strain relationship curve Figure 2 In the case shown, the target uniaxial compressive strength, failure time, and yield deviation of the coal rock sample can be determined from the stress-strain relationship curve, and then the area enclosed by the loading curve and the X-axis, and the area enclosed by the unloading curve and the X-axis in the first stage can be calculated, which represent the first dissipated energy in the first stage. and the first accumulated elastic energy The area enclosed by the pre-peak curve and the X-axis and the area enclosed by the post-peak curve and the X-axis in the second stage are calculated, which respectively represent the pre-peak input energy U2 (second dissipated energy and second accumulated elastic energy) and post-peak loss energy U3 in the second stage.

[0047] Among them, ε B , ε A , ε M , ε C For different stress energy values, σ C is the target uniaxial compressive strength, σ q is the yield deviation, M, C represents the M , ε C The stress value at .

[0048] Alternatively, the failure time may be the time from peak strength to loss of bearing capacity in a stress-strain curve.

[0049] Step 104, based on the first dissipated energy, the first accumulated elastic energy, the second dissipated energy, the second accumulated elastic energy and the post-peak loss energy, the target uniaxial compressive strength, and the yield deviation, calculate the total residual release energy within the destruction time of the coal rock sample.

[0050] The yield deviation is obtained by extending the linear elastic section of the stress-strain curve to a tangent line at 0.5 times the peak strength.

[0051] Alternatively, in a stress-strain curve such as Figure 2 In the case shown, the calculation formula for the second accumulated elastic energy can be:

[0052]

[0053] The total remaining released energy can be calculated as:

[0054]

[0055] Among them, U l It is the sum of the post-peak loss energy U3 and the second dissipated energy in the second stage pre-peak input energy U2, and d represents the differential.

[0056] Step 105: Based on the loading rate, the failure time is converted into an equivalent dynamic failure time for the coal rock sample to be destroyed.

[0057] In some embodiments, the release rate of the total residual energy of coal is closely related to the dynamic instability characteristics of coal, and the destruction time after the peak of the coal sample should be considered. ) affects the failure time of coal rock samples. By specifying the dynamic failure time (DT) of coal rock and drawing on the loading rate of the dynamic failure time, the present invention proposes converting the real failure time (t) into the equivalent dynamic failure time (DT*) for evaluation. The calculation method of the equivalent dynamic failure time is as follows:

[0058]

[0059] Where E is the elastic modulus of the sample at 0.5 times the average uniaxial compressive strength.

[0060] Step 106: Calculate the total remaining released energy release rate based on the total remaining released energy and the equivalent dynamic failure time to evaluate the dynamic instability characteristics of the coal rock.

[0061] In some embodiments, when the total remaining release energy is ΔW and the equivalent dynamic failure time DT * In the case of , the total remaining release energy release rate is calculated as:

[0062]

[0063] The comprehensive evaluation test method for the dynamic instability characteristics of coal rock in the embodiment of the present invention obtains a coal rock sample; based on the uniaxial compressive strength of the coal rock sample, the uniaxial loading of the coal rock sample is controlled at different loading rates to obtain the stress-strain relationship curves of the first and second stages before the destruction of the coal rock sample; the first accumulated elastic energy and the first dissipated energy of the first stage, and the second accumulated elastic energy, the second dissipated energy and the post-peak loss energy of the second stage are calculated according to the stress-strain relationship curve; the total residual release energy of the coal rock sample is then calculated; and based on the equivalent dynamic destruction time converted from the total residual release energy and the destruction time, the release rate of the total residual release energy is calculated to evaluate the dynamic instability characteristics of the coal rock. Therefore, by introducing the uniaxial compressive strength, yield deviation, accumulated elastic energy and equivalent dynamic destruction time, the release rate of the total residual release energy is calculated, thereby improving the accuracy and precision of evaluating the dynamic instability of the coal rock.

[0064] In order to clearly illustrate the above embodiment, this embodiment further provides a comprehensive evaluation test method for coal rock dynamic instability characteristics. Figure 3 A flow chart of another comprehensive evaluation test method for coal rock dynamic instability characteristics provided by an embodiment of the present invention.

[0065] like Figure 3 As shown, the method may include the following steps:

[0066] Step 301: Obtain coal rock samples.

[0067] Step 302 , based on the average uniaxial compressive strength of the coal rock sample, establish a stress-strain relationship curve when the coal rock sample is loaded at different loading rates in the first and second stages within the failure time of the coal rock sample.

[0068] Step 303, based on the target uniaxial compressive strength, failure time, and yield deviation of the coal rock sample in the stress-strain relationship curve, calculate the first dissipated energy and first accumulated elastic energy input in the first stage, as well as the second accumulated elastic energy, second dissipated energy, and post-peak loss energy input in the second stage.

[0069] Step 304, based on the first dissipated energy, the first accumulated elastic energy, the second dissipated energy, the second accumulated elastic energy and the post-peak loss energy, the target uniaxial compressive strength, and the yield deviation, calculate the total residual release energy within the destruction time of the coal rock sample.

[0070] It should be noted that, for the specific implementation of steps 301 to 304 , reference may be made to the relevant description in the above embodiment.

[0071] Step 305 : Obtain a residual impact energy index obtained by the ratio of the sum of the first accumulated elastic energy and the second accumulated elastic energy to the total residual release energy.

[0072] Alternatively, in a stress-strain curve such as Figure 2 As shown, the total remaining release energy is ΔW and the sum of the first accumulated elastic energy and the second accumulated elastic energy is U e In this case, the calculation formula of the residual impact energy index can be:

[0073]

[0074] Step 306: Determine the maximum degree of dynamic instability of the coal rock according to the residual impact energy index.

[0075] Optionally, the smaller the residual impact energy index is, the greater the degree of dynamic instability of the coal rock is; conversely, the larger the residual impact energy index is, the smaller the degree of dynamic instability of the coal rock is.

[0076] The comprehensive evaluation test method for the dynamic instability characteristics of coal rock in an embodiment of the present invention obtains a coal rock sample; based on the uniaxial compressive strength of the coal rock sample, controls the uniaxial loading of the coal rock sample at different loading rates to obtain the stress-strain relationship curves of the first and second stages before the destruction of the coal rock sample; calculates the first accumulated elastic energy and the first dissipated energy of the first stage, and the second accumulated elastic energy, the second dissipated energy and the post-peak loss energy of the second stage according to the stress-strain relationship curve; and then calculates the total residual release energy of the coal rock sample; obtains the residual impact energy index obtained by the ratio of the sum of the first accumulated elastic energy and the second accumulated elastic energy to the total residual release energy, and determines the maximum dynamic instability degree of the coal rock according to the residual impact energy index, thereby calculating the total residual impact energy index through the first accumulated elastic energy, the second accumulated elastic energy and the total residual release energy to determine the possibility and degree of danger of dynamic disasters occurring in the coal rock instability process.

[0077] In order to implement the above embodiment, the present invention also proposes a comprehensive evaluation and testing device for coal and rock dynamic instability characteristics.

[0078] Figure 4 A schematic structural diagram of a comprehensive evaluation and testing device for dynamic instability characteristics of coal and rock provided in an embodiment of the present invention.

[0079] like Figure 4 As shown, the comprehensive evaluation and testing device 40 for coal-rock dynamic instability characteristics includes: a first acquisition module 41 , a construction module 42 , a first calculation module 43 , a second calculation module 44 , a conversion module 45 and a third calculation module 46 .

[0080] The first acquisition module 41 is used to obtain coal and rock samples;

[0081] A construction module 42 is configured to establish, based on the average uniaxial compressive strength of the coal rock sample, a stress-strain relationship curve when the coal rock sample is loaded at different loading rates in the first and second stages within the failure time of the coal rock sample;

[0082] A first calculation module 43 is configured to calculate the first dissipated energy and the first accumulated elastic energy input in the first stage, and the second accumulated elastic energy, the second dissipated energy, and the post-peak loss energy input in the second stage based on the target uniaxial compressive strength, failure time, and yield deviation of the coal rock sample in the stress-strain relationship curve;

[0083] a second calculation module 44 for calculating the total remaining released energy within the destruction time of the coal rock sample based on the first dissipated energy, the first accumulated elastic energy, the second dissipated energy, the second accumulated elastic energy and the post-peak loss energy, the target uniaxial compressive strength, and the yield deviation;

[0084] A conversion module 45 is configured to convert the failure time into an equivalent dynamic failure time of the coal rock sample based on the loading rate;

[0085] The third calculation module 46 is used to calculate the release rate of the total residual released energy according to the total residual released energy and the equivalent dynamic failure time, so as to evaluate the dynamic instability characteristics of the coal rock.

[0086] Furthermore, in a possible implementation of the embodiment of the present invention, the first acquisition module 41 is specifically configured to:

[0087] Collecting a plurality of initial coal rock samples having coal rock characteristics, wherein the height orientation of the initial coal rock samples should be perpendicular to the bedding plane of the coal, and the coal rock should have no obvious cracks;

[0088] The initial coal rock sample is subjected to standardized sample processing to obtain a coal rock sample whose unevenness is smaller than a preset size and whose axial deviation is smaller than a preset angle.

[0089] Furthermore, in a possible implementation of the embodiment of the present invention, the construction module 42 is specifically configured to:

[0090] Based on the average uniaxial compressive strength of the coal rock sample, loading the sample at a loading rate controlled by a first preset stress to a preset percentage of the average uniaxial compressive strength, and then unloading the stress to a second preset stress after stopping the loading as the first stage;

[0091] After the unloading stress reaches the second preset stress, the coal rock sample is loaded to a damaged state at a strain-controlled loading rate at a preset time interval as a second stage;

[0092] A stress-strain relationship curve between the target uniaxial compressive strength and stress energy of the coal rock sample in the first stage and the second stage is established within the destruction time of the coal rock sample.

[0093] Furthermore, in a possible implementation of the embodiment of the present invention, the first calculation module 43 is specifically configured to:

[0094] Calculating the first dissipated energy and the first accumulated elastic energy input in the first stage according to the target uniaxial compressive strength, failure time, and yield deviation of the coal rock sample in the stress-strain relationship curve;

[0095] The second dissipated energy and the second accumulated elastic energy are calculated based on the first dissipated energy, the target uniaxial compressive strength, the yield deviation, and the first accumulated elastic energy.

[0096] Furthermore, in a possible implementation of the embodiment of the present invention, the yield deviation is obtained by extending the linear elastic section of the stress-strain relationship curve to obtain a tangent at 0.5 times the peak strength.

[0097] Based on the above embodiment, the present invention further provides a possible implementation of a device for comprehensive evaluation and testing of coal and rock dynamic instability characteristics. On the basis of the above embodiment, the device further includes:

[0098] a second acquisition module, configured to acquire a residual impact energy index obtained by calculating the ratio of the sum of the first accumulated elastic energy and the second accumulated elastic energy to the total residual release energy;

[0099] A determination module is used to determine the maximum degree of dynamic instability of the coal rock according to the residual impact energy index.

[0100] It should be noted that the above explanation of the method embodiment is also applicable to the device of this embodiment and will not be repeated here.

[0101] The comprehensive evaluation and testing device for the dynamic instability characteristics of coal rock in the embodiment of the present invention obtains a coal rock sample; based on the uniaxial compressive strength of the coal rock sample, controls the uniaxial loading of the coal rock sample at different loading rates to obtain the stress-strain relationship curves of the first and second stages before the destruction of the coal rock sample; calculates the first accumulated elastic energy and the first dissipated energy of the first stage, and the second accumulated elastic energy, the second dissipated energy and the post-peak loss energy of the second stage according to the stress-strain relationship curve; and then calculates the total residual release energy of the coal rock sample; and based on the equivalent dynamic destruction time converted from the total residual release energy and the destruction time, calculates the release rate of the total residual release energy to evaluate the dynamic instability characteristics of the coal rock. Therefore, by introducing the uniaxial compressive strength, yield deviation, accumulated elastic energy and equivalent dynamic destruction time, the release rate of the total residual release energy is calculated, thereby improving the accuracy and precision of evaluating the dynamic instability of the coal rock.

[0102] In order to implement the above embodiment, the present invention further provides an electronic device, including:

[0103] at least one processor; and

[0104] a memory communicatively connected to the at least one processor; wherein,

[0105] The memory stores instructions that can be executed by the at least one processor. The instructions are executed by the at least one processor to enable the at least one processor to perform the aforementioned method.

[0106] In order to implement the above embodiment, the present invention further proposes a non-transitory computer-readable storage medium storing computer instructions, where the computer instructions are used to enable the computer to execute the above method.

[0107] In order to implement the above embodiments, the present invention further provides a computer program product, comprising a computer program, which implements the above method when executed by a processor.

[0108] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0109] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0110] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0111] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0112] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0113] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0114] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing module, or each unit may exist physically separately, or two or more units may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may also be stored in a computer-readable storage medium.

[0115] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and are not to be construed as limiting the present invention. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A comprehensive evaluation and testing method for coal rock dynamic instability characteristics, characterized by: The method comprises: Obtain coal rock samples; Based on the average uniaxial compressive strength of the coal rock sample, a stress-strain relationship curve is established when the coal rock sample is loaded at different loading rates in the first and second stages within the failure time of the coal rock sample; Calculating the first dissipated energy and the first accumulated elastic energy input in the first stage, and the second accumulated elastic energy, the second dissipated energy, and the post-peak loss energy input in the second stage according to the target uniaxial compressive strength, failure time, and yield deviation of the coal rock sample in the stress-strain relationship curve; Calculating the total residual released energy within the destruction time of the coal rock sample based on the first dissipated energy, the first accumulated elastic energy, the second dissipated energy, the second accumulated elastic energy and the post-peak loss energy, the target uniaxial compressive strength, and the yield deviation; Based on the loading rate, converting the failure time into an equivalent dynamic failure time for the coal rock sample to be destroyed; According to the total residual released energy and the equivalent dynamic failure time, the total residual released energy release rate is calculated to evaluate the dynamic instability characteristics of coal and rock; The total remaining released energy is calculated as follows: Where U e Characterizes the second accumulated elastic energy, which is determined by the first dissipated energy, the target uniaxial compressive strength, the yield deviation and the first accumulated elastic energy; ΔW characterizes the total residual release energy; U l is the sum of the post-peak loss energy and the second dissipated energy, d represents the differential; in the stress-strain relationship curve, ε B , ε A , ε M , ε C For different stress energy values, σ C is the target uniaxial compressive strength, σ q is the yield deviation; The equivalent dynamic failure time is calculated as follows: Wherein, DT* represents the equivalent dynamic failure time, r represents the loading rate, t is the failure time, and E is the elastic modulus of the sample at 0.5 times the average uniaxial compressive strength; The total remaining release energy release rate is calculated as follows: Where W c Characterize the release rate of the total remaining released energy.

2. The method according to claim 1, characterized in that The obtaining of coal rock samples comprises: Collecting a plurality of initial coal rock samples having coal rock characteristics, wherein the height orientation of the initial coal rock samples should be perpendicular to the bedding plane of the coal, and the coal rock should have no obvious cracks; The initial coal rock sample is subjected to standardized sample processing to obtain a coal rock sample whose unevenness is smaller than a preset size and whose axial deviation is smaller than a preset angle.

3. The method according to claim 1, characterized in that The stress-strain relationship curve when the coal rock sample is loaded at different loading rates in the first and second stages based on the uniaxial compressive strength of the coal rock sample and established within the failure time of the coal rock sample, includes: Based on the average uniaxial compressive strength of the coal rock sample, loading the sample at a loading rate controlled by a first preset stress to a preset percentage of the average uniaxial compressive strength, and then unloading the stress to a second preset stress after stopping the loading as the first stage; After the unloading stress reaches the second preset stress, the coal rock sample is loaded to a damaged state at a strain-controlled loading rate at a preset time interval as a second stage; A stress-strain relationship curve between the target uniaxial compressive strength and stress energy of the coal rock sample in the first stage and the second stage is established within the destruction time of the coal rock sample.

4. The method according to claim 1, wherein The first dissipated energy and first accumulated elastic energy input in the first stage, and the second accumulated elastic energy, second dissipated energy, and post-peak loss energy input in the second stage are calculated based on the target uniaxial compressive strength, failure time, and yield deviation of the coal rock sample in the stress-strain relationship curve, including: Calculating the first dissipated energy and the first accumulated elastic energy input in the first stage according to the target uniaxial compressive strength, failure time, and yield deviation of the coal rock sample in the stress-strain relationship curve; The second dissipated energy and the second accumulated elastic energy are calculated based on the first dissipated energy, the target uniaxial compressive strength, the yield deviation, and the first accumulated elastic energy.

5. The method according to claim 4, characterized in that The yield deviation is obtained by extending the linear elastic section of the stress-strain curve to a tangent line at 0.5 times the peak strength.

6. The method according to claim 1, wherein The method further comprises: obtaining a residual impact energy index obtained by obtaining a ratio of the sum of the first accumulated elastic energy and the second accumulated elastic energy to the total residual release energy; The maximum degree of dynamic instability of the coal rock is determined according to the residual impact energy index.

7. A comprehensive evaluation and testing device for coal and rock dynamic instability characteristics, characterized in that: The device comprises: A first acquisition module is used to obtain coal and rock samples; A construction module is used to establish, based on the average uniaxial compressive strength of the coal rock sample, a stress-strain relationship curve when the coal rock sample is loaded at different loading rates in the first stage and the second stage within the failure time of the coal rock sample; a first calculation module, configured to calculate the first dissipated energy and the first accumulated elastic energy input in the first stage, and the second accumulated elastic energy, the second dissipated energy, and the post-peak loss energy input in the second stage, based on the target uniaxial compressive strength, the failure time, and the yield deviation of the coal rock sample in the stress-strain relationship curve; a second calculation module, configured to calculate the total residual released energy within the destruction time of the coal rock sample based on the first dissipated energy, the first accumulated elastic energy, the second dissipated energy, the second accumulated elastic energy and the post-peak loss energy, the target uniaxial compressive strength, and the yield deviation; a conversion module, configured to convert the failure time into an equivalent dynamic failure time of the coal rock sample based on the loading rate; The third calculation module is used to calculate the release rate of the total residual release energy based on the total residual release energy and the equivalent dynamic failure time to evaluate the dynamic instability characteristics of coal and rock; The total remaining released energy is calculated as follows: Where U e Characterizes the second accumulated elastic energy, which is determined by the first dissipated energy, the target uniaxial compressive strength, the yield deviation and the first accumulated elastic energy; ΔW characterizes the total residual release energy; U l is the sum of the post-peak loss energy and the second dissipated energy, d represents the differential; in the stress-strain relationship curve, ε B , ε A , ε M , ε C For different stress energy values, σ C is the target uniaxial compressive strength, σ q is the yield deviation; The equivalent dynamic failure time is calculated as follows: Wherein, DT* represents the equivalent dynamic failure time, r represents the loading rate, t is the failure time, and E is the elastic modulus of the sample at 0.5 times the average uniaxial compressive strength; The total remaining release energy release rate is calculated as follows: Where W c Characterize the release rate of the total remaining released energy.

8. The device according to claim 7, characterized in that The device further comprises: a second acquisition module, configured to acquire a residual impact energy index obtained by calculating a ratio of the first accumulated elastic energy to the total residual release energy; A determination module is used to determine the maximum degree of dynamic instability of the coal rock according to the residual impact energy index.

9. An electronic device, characterized in that: include: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 6.

10. A non-transitory computer-readable storage medium storing computer instructions, characterized in that: The computer instructions are used to cause the computer to execute the method according to any one of claims 1 to 6.

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