Method, device and medium for numerical simulation of rock acoustic emission

Abstract

The present invention discloses a method, device and medium for realizing numerical simulation of rock acoustic emission. The method first determines the position of the acoustic emission event by extracting the node coordinates of all damaged units, that is, realizes acoustic emission positioning, uses the time of the initial damage to represent the time when the acoustic emission event occurs, and determines the number of acoustic emission events by counting the number of damaged units generated over time. Then, the maximum value of the total damage dissipation energy of the damaged unit in the entire simulation process is extracted to represent the magnitude of the energy of the acoustic emission event. Finally, the tensile fracture energy and shear fracture energy of all damaged units are extracted to characterize their fracture types. Through this method, an acoustic emission positioning diagram, a relationship curve between the number of acoustic emission events and the acoustic emission energy with time and load, and the fracture type of the crack can be obtained, and all parameter values ​​obtained by the acoustic emission test can be obtained. The present invention has a wider range of applications, stronger applicability, simple operation, easy-to-understand principles, and is more feasible.

Description

Technical Field

[0001] The present invention relates to the field of numerical simulation technology, and more specifically, to a method, device and medium for realizing numerical simulation of rock acoustic emission. Background Art

[0002] Acoustic emission refers to the phenomenon that when a material or component is deformed or cracked during stress, strain energy is released in the form of elastic waves. Acoustic emission technology is a technology that uses acoustic emission signals to perform dynamic nondestructive testing on materials or components. By processing and analyzing the received waveform signal, the location of the crack and the type of crack rupture can be obtained, so it is widely used in the field of rock mechanics. Acoustic emission technology can be applied to indoor test scales to monitor the rupture process of small-scale specimens. It can also be used at the engineering scale. When monitoring at the engineering scale, acoustic emission is called microseismic monitoring. Indoor tests can be carried out on laboratory-scale specimens to obtain basic rock mechanical properties and mechanical laws. However, it is difficult to carry out field tests at the engineering scale, especially with the advancement of deep rock mass engineering today, deep rock mass in-situ tests cannot be carried out. Therefore, numerical simulation methods are currently used to study rock mass rupture problems of different scales. As an effective means of crack monitoring, the acoustic emission method can also be applied to the field of numerical simulation. Through the implementation of the acoustic emission numerical simulation method, the entire process of crack initiation, expansion, and penetration can be analyzed more accurately, which helps to reveal the true rupture mechanism of the rock mass, thereby guiding the engineering construction design.

[0003] The generation, expansion and penetration of cracks are the direct factors causing rock fracture and instability. The occurrence of many rock engineering disasters is related to the crack initiation, expansion and fracture process. Therefore, studying the rock fracture mechanism is undoubtedly a very meaningful work. When rocks break, energy is generated, and the phenomenon of energy being released in the form of elastic waves is called acoustic emission. Based on this principle, acoustic emission technology has been rapidly developed and widely used in the field of rock mechanics. Compared with other methods, the use of acoustic emission technology can continuously and in real time monitor the generation and development of internal microcracks in rocks under load, and can locate the crack position.

[0004] Acoustic emission technology can be used to capture elastic waves generated by rupture at multiple points. By capturing waveform data and time difference at multiple points, the location where the elastic wave is generated, that is, the location where the crack is generated, can be calculated. Similarly, the time of the elastic wave can be recorded to obtain the time when the crack is generated. Each acoustic emission signal is recorded as an acoustic emission event number. The time and location of the acoustic emission event number can be counted, so that the distribution state of the crack under different loading times can be obtained. In addition, the crack rupture type can be obtained by analyzing and processing the received waveform. Common crack rupture types include tensile rupture, shear rupture, and tensile-shear mixed rupture. Existing studies have shown that different crack types show different waveforms. Therefore, the acoustic emission method can be used to obtain specific rupture types. The acquisition of rupture types is of great significance for guiding engineering design. In addition, different elastic waves have different energies and different magnitudes of rupture. Obtaining the energy generated by rupture through acoustic emission can obtain the energy level of rupture under different mechanical states or at different locations of the rock mass. In summary, the main parameters obtained by the acoustic emission method are: the number of acoustic emission events, the acoustic emission energy, the rupture type, and the relationship between the number of events and the energy with time and load.

[0005] However, the application of acoustic emission in numerical simulation is not perfect at present, and it is obviously unrealistic to fully realize the acoustic emission indicators of indoor physical experiments in numerical simulation. Therefore, it is necessary to establish a simple and easy-to-use acoustic emission numerical simulation method.

[0006] Patent No. 202211109855.9 discloses a method for simulating and analyzing acoustic emission of rock fracture based on finite element-discrete element coupling. The specific steps are: 1. Obtain the acoustic emission data of the current time step when the rock fractures, and obtain the acoustic emission event information according to the acoustic emission data. The acoustic emission event information includes the state of the acoustic emission event and the microcrack information corresponding to the microcracks contained in the acoustic emission event; 2. Based on the microcrack information of the acoustic emission event, obtain the fracture area of ​​the acoustic emission event in the inactive state, and calculate the node force change components of all finite elements in the fracture area; 3. Based on all the node force change components, obtain the moment tensor; 4. Based on the moment tensor, obtain the analysis results of the macro crack.

[0007] The above patent calculates the moment tensor of the acoustic emission event, analyzes the macro crack type according to the moment tensor, and obtains the analysis result of the macro crack type. It is a finite element-discrete element coupled rock fracture acoustic emission simulation analysis method. However, this method is computationally complex, which increases the computational workload, and the complex calculation also reduces the accuracy of acoustic emission monitoring. Summary of the invention

[0008] The present invention is provided to solve the above-mentioned problems existing in the prior art. Therefore, a method, device and medium for realizing numerical simulation of rock acoustic emission are needed. A storage file is designed during the simulation process, which can be used to store the required acoustic emission data information. By extracting the data therein, the change of the number of acoustic emission events and the acoustic emission energy over time and the relationship curve with the load can be obtained. At the same time, the simulation of acoustic emission positioning can be realized to show the real fracture morphology. In real physical experiments, acoustic emission positioning also needs to set a threshold in order to eliminate positioning points with smaller energy. This method also realizes this function, and the result diagram of acoustic emission positioning under different threshold conditions can be obtained. In addition, the acoustic emission energy and crack rupture type can also be obtained, which can fully realize the common data monitored by acoustic emission technology.

[0009] According to a first aspect of the present invention, a method for implementing numerical simulation of rock acoustic emission is provided, the method comprising:

[0010] Obtaining node coordinate information of a damaged unit and the time when a damage variable of the damaged unit is generated, wherein the damage variable is stiffness degradation, and the stiffness degradation is obtained according to a stress change in the damaged unit during a simulation process;

[0011] Determine the position information of the damaged unit according to the node coordinate information of the damaged unit;

[0012] Each damaged unit is regarded as an acoustic emission event, and according to the time when the damaged unit is damaged, the statistics of acoustic emission events at different times are realized;

[0013] The energy dissipated per unit volume of the damaged unit during the simulation is taken as the energy of the acoustic emission event;

[0014] According to the number of damaged units and the number of damaged units generated at different times, the curve of acoustic emission events changing with time is obtained;

[0015] An acoustic emission localization map is obtained according to the position information of the damaged unit. In the acoustic emission localization map, one point represents one acoustic emission event, and the size of the point is determined according to the energy of the corresponding acoustic emission event.

[0016] Furthermore, the energy dissipated per unit volume of the damaged unit during the simulation is calculated by the following formula:

[0017] U d =UU e ;

[0018]

[0019]

[0020] Among them, U drepresents the energy dissipated per unit volume of the damaged unit, U represents the total work done by the principal stress in the direction of the principal strain, and U e represents the releasable elastic strain energy stored per unit volume, ε i represents the work done by the i-th principal stress in the direction of the corresponding principal stress, σ i represents the i-th principal stress, represents the elastic strain corresponding to the i-th principal stress.

[0021] Further, after taking the energy dissipated within the unit volume of the damaged unit during the simulation as the energy of the acoustic emission event, the method further comprises:

[0022] Based on the set energy threshold, acoustic emission events with energy less than the energy threshold are eliminated.

[0023] Furthermore, the method further comprises:

[0024] The fracture energy of the damaged unit is obtained, wherein the fracture energy includes tensile fracture energy and shear fracture energy, and the rupture type of the acoustic emission event is characterized by the ratio of the tensile fracture energy to the shear fracture energy.

[0025] Furthermore, in the acoustic emission localization map, the rupture types of different acoustic emission events are characterized by the color / shape of the points representing the acoustic emission events.

[0026] According to a second aspect of the present invention, a device for implementing numerical simulation of rock acoustic emission is provided, the device comprising:

[0027] A data acquisition module is configured to acquire node coordinate information of a damaged unit and a time when a damage variable of the damaged unit is generated, wherein the damage variable is stiffness degradation, and the stiffness degradation is obtained according to a stress change in the damaged unit during a simulation process;

[0028] A damage location module, configured to determine the location information of the damaged unit according to the node coordinate information of the damaged unit;

[0029] The time statistics module is configured to take each damaged unit as an acoustic emission event, and realize the statistics of acoustic emission events at different times according to the time when the damaged unit is damaged;

[0030] An energy calculation module is configured to use the energy dissipated within a unit volume of a damage unit during a simulation as the energy of an acoustic emission event;

[0031] A curve determination module is configured to obtain a curve of acoustic emission events changing with time according to the number of damaged units and the number of damaged units generated at different times;

[0032] The positioning map making module is configured to obtain an acoustic emission positioning map according to the position information of the damaged unit, wherein a point in the acoustic emission positioning map represents an acoustic emission event, and the size of the point is determined according to the energy of the corresponding acoustic emission event.

[0033] Furthermore, the energy calculation module is further configured as follows:

[0034] The energy dissipated per unit volume of the damaged element during the simulation is calculated using the following formula:

[0035] U d =UU e ;

[0036]

[0037]

[0038] Among them, U d represents the energy dissipated per unit volume of the damaged unit, U represents the total work done by the principal stress in the direction of the principal strain, and U e represents the releasable elastic strain energy stored per unit volume, ε i represents the work done by the i-th principal stress in the direction of the corresponding principal stress, σ i represents the i-th principal stress, represents the elastic strain corresponding to the i-th principal stress.

[0039] Furthermore, the device further comprises an energy screening module, and the energy screening module is further configured to:

[0040] Based on the set energy threshold, acoustic emission events with energy less than the energy threshold are eliminated.

[0041] Furthermore, the device further includes a type determination module, and the type determination module is further configured to:

[0042] The fracture energy of the damaged unit is obtained, wherein the fracture energy includes tensile fracture energy and shear fracture energy, and the rupture type of the acoustic emission event is characterized by the ratio of the tensile fracture energy to the shear fracture energy.

[0043] According to a third aspect of the present invention, there is provided a readable storage medium storing one or more programs, wherein the one or more programs can be executed by one or more processors to implement the method as described above.

[0044] The present invention has at least the following beneficial effects:

[0045] The present invention can realize the numerical simulation of acoustic emission, and can analyze the acoustic emission parameters under different loading times: the number of acoustic emission events, the cumulative number of acoustic emission events, the acoustic emission energy, the change law of the cumulative acoustic emission energy and its change law with load. At the same time, it can simulate the positioning of acoustic emission events, intuitively show the distribution of cracks, and characterize the energy size and fracture type of acoustic emission event points. In addition, it can eliminate tiny acoustic emission events by setting a threshold, so that the results are more realistic. The realization of this method has laid a solid foundation for future research on rock fracture. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A schematic diagram of a method for implementing numerical simulation of rock acoustic emission according to an embodiment of the present invention is shown.

[0047] Figure 2 A flow chart of a method for implementing numerical simulation of rock acoustic emission according to an embodiment of the present invention is shown.

[0048] Figure 3 The invention shows an energy screening flow chart of a method for implementing numerical simulation of rock acoustic emission according to an embodiment of the invention.

[0049] Figure 4 A partial flow chart of a method for implementing numerical simulation of rock acoustic emission according to an embodiment of the present invention is shown.

[0050] Figure 5 A graph of the number of acoustic emission events versus load according to an embodiment of the present invention is shown.

[0051] Figure 6 A graph of acoustic emission energy and load according to an embodiment of the present invention is shown.

[0052] Figure 7 An acoustic emission localization diagram according to an embodiment of the present invention is shown.

[0053] Figure 8 A diagram showing a real fracture morphology according to an embodiment of the present invention is shown.

[0054] Fig. 9 The acoustic emission localization diagram under different thresholds selected according to an embodiment of the present invention is shown.

[0055] Fig.10 The acoustic emission localization diagrams at different times according to an embodiment of the present invention are shown. DETAILED DESCRIPTION

[0056] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings and specific embodiments, but are not intended to limit the present invention. For the various steps described herein, if there is no necessity for a causal relationship between each other, the order in which they are described as examples herein should not be regarded as a limitation, and those skilled in the art should know that they can be adjusted in order, as long as the logic between them is not destroyed, resulting in the inability to implement the entire process.

[0057] The embodiment of the present invention provides a method for realizing numerical simulation of rock acoustic emission. Figure 1 As shown in the figure, it is the implementation principle diagram of this method. First, the location of the acoustic emission event is determined by extracting the node coordinates of all damaged units, that is, the acoustic emission positioning is realized. The time of the acoustic emission event is represented by the time of the initial damage, and the number of acoustic emission events is determined by counting the number of damaged units generated over time. Then, the maximum value of the total damage dissipation energy of the damaged unit in the entire simulation process is extracted to represent the energy of the acoustic emission event. Finally, the tensile fracture energy and shear fracture energy of all damaged units are extracted to characterize their fracture types. Through this method, the acoustic emission positioning diagram (that is, the location of the damage), the relationship curve between the number of acoustic emission events and the acoustic emission energy with time and load, and the fracture type of the crack can be obtained, and all parameter values ​​obtained by the acoustic emission test can be obtained. Compared with other methods, this method has a wider range of applications, stronger applicability, simple operation, easy-to-understand principles, and is more feasible.

[0058] Specifically, if Figure 2 FIG. 1 is a flow chart of a method for implementing numerical simulation of rock acoustic emission, and the method comprises the following steps:

[0059] Step S100, obtaining node coordinate information of a damaged unit and the time when a damage variable of the damaged unit is generated, wherein the damage variable is stiffness degradation, and the stiffness degradation is obtained according to the stress change in the damaged unit during the simulation process.

[0060] It should be noted that the above parameters, such as the node coordinate information of the damaged unit and the acquisition of the damage variable of the damaged unit, are monitored and acquired during the model simulation process. The models that can be applied in this embodiment include but are not limited to some existing models, such as the cohesive zone model, etc. The process of numerical simulation based on the existing model adopts the currently known numerical simulation method. This embodiment focuses on the process of analyzing the data generated by the numerical simulation process.

[0061] For example, a damage variable is established, and the change in stiffness is obtained by monitoring the stress and strain changes in a unit or region during the simulation process, and the stiffness degradation is used as the damage variable. During the numerical simulation of the model, all units in the model are traversed, all damaged units are counted, and the node coordinate information of the unit and the time when the damage variable begins to be generated are stored.

[0062] Step S200: determining the position information of the damaged unit according to the node coordinate information of the damaged unit.

[0063] That is, for the damaged unit, the node coordinate information is used to determine the position of the damaged unit, thereby realizing the positioning of the acoustic emission.

[0064] In step S300, each damaged unit is regarded as an acoustic emission event, and according to the time when the damaged unit is damaged, the acoustic emission events at different times are counted.

[0065] In this step, each damaged unit is counted as an acoustic emission event number. According to the time when the damaged unit is stored, the number of acoustic emission events at different times can be counted.

[0066] Step S400, taking the energy dissipated in the unit volume of the damaged unit during the simulation process as the energy of the acoustic emission event.

[0067] Specifically, the energy dissipated per unit volume of the damaged element during the simulation is calculated using the following formula:

[0068] U d =-UU e ;

[0069]

[0070]

[0071] Among them, U d represents the energy dissipated per unit volume of the damaged unit, U represents the total work done by the principal stress in the direction of the principal strain, and U e represents the releasable elastic strain energy stored per unit volume, ε i represents the work done by the i-th principal stress in the direction of the corresponding principal stress, σ i represents the i-th principal stress, represents the elastic strain corresponding to the i-th principal stress.

[0072] In this embodiment, the maximum energy dissipated per unit volume of the damaged unit during the entire loading process is extracted, and the maximum energy dissipated per unit volume is used to characterize the energy size of the acoustic emission event. Taking a damaged unit as an example, during the model loading process, the energy dissipated per unit volume of multiple damaged units is calculated. d , the energy dissipated in the unit volume of the multiple damaged units is U d Among them, the maximum value is taken as the energy of the acoustic emission event.

[0073] In some embodiments, Figure 3 As shown, after the energy dissipated in the unit volume of the damaged unit during the simulation is used as the energy of the acoustic emission event, that is, after the energy of the acoustic emission event is obtained, the method further includes step S401, based on the set energy threshold, eliminating the acoustic emission events whose energy is less than the energy threshold. It should be noted that the energy threshold set here is determined according to the different models built and their simulation conditions, and the size of the set energy threshold is not specifically limited in this embodiment.

[0074] Just as an example, after taking the energy dissipated per unit volume of the damaged unit in the simulation process as the energy of the acoustic emission event, the energy dissipated per unit volume of each damaged unit is stored in a specified file, an energy threshold is set, and acoustic emission event points with smaller energy are eliminated. The file storing the energy is updated to eliminate tiny acoustic emission events, making the results more realistic.

[0075] Step S500, obtaining a curve of acoustic emission events changing with time according to the number of damaged units and the number of damaged units generated at different times.

[0076] Step S600, obtaining an acoustic emission localization map according to the position information of the damaged unit, wherein one point in the acoustic emission localization map represents one acoustic emission event, and the size of the point is determined according to the energy of the corresponding acoustic emission event.

[0077] Exemplarily, by extracting all the damaged unit information in the storage file, the number of damaged units (i.e., the number of acoustic emission times) is obtained, the number of damaged units generated at different times is counted (i.e., the time-varying curve of the number of acoustic emission events is obtained), and the position information of the damaged units is extracted to obtain an acoustic emission localization map. In the acoustic emission localization map, one point is used to represent one acoustic emission event. The energy dissipated per unit volume of the stored damaged unit is further extracted, and the energy value is used as the size of the event point in the acoustic emission localization map to intuitively represent the energy level of the acoustic emission event point.

[0078] In some embodiments, before obtaining the acoustic emission event variation curve over time according to the number of damaged units and the number of damaged units generated at different times, as shown in FIG. Figure 4 As shown, the method also includes:

[0079] Step S2501, obtaining the fracture energy of the damaged unit, wherein the fracture energy includes tensile fracture energy and shear fracture energy, and the ratio of tensile fracture energy to shear fracture energy is used to characterize the rupture type of the acoustic emission event.

[0080] For example, the specific value of the rupture type that characterizes the acoustic emission event can be calculated by the following formula:

[0081]

[0082] Among them, G n represents the mode I tensile fracture energy, G s represents the mode II slip fracture energy, G t represents the type III tear fracture energy, and M is the specifically calculated ratio. By comparing the ratio with the set threshold range, the rupture type of the acoustic emission event can be determined.

[0083] The above method can realize the distribution curve of the number of acoustic emission events over time ( Figure 5 ), and the acoustic emission energy distribution curve over time ( Figure 6 ).

[0084] Through the above analysis, an acoustic emission positioning map can be drawn, which can reflect: ① the location of the acoustic emission event point; ② the energy of the acoustic emission event point; ③ the rupture type of the acoustic emission event. Comparing the obtained acoustic emission positioning map with the actual rupture morphology can verify the accuracy of the acoustic emission positioning of this program. Figure 7 , Figure 8 shown.

[0085] Considering that in real experiments, acoustic emission positioning often sets a threshold in order to eliminate positioning points with smaller energy, the present invention also realizes this function, such as Fig. 9 Shown are the acoustic emission localization results given different thresholds.

[0086] At the same time, considering the time of acoustic emission events, that is, monitoring the crack expansion process, this method realizes the change process of acoustic emission positioning over time, such as Fig.10 As shown, the dynamic change process of acoustic emission positioning and the location, energy, rupture type and other information of the acoustic emission event point generated at each time node can be easily observed.

[0087] In addition, although exemplary embodiments have been described herein, the scope includes any and all embodiments based on the present invention with equivalent elements, modifications, omissions, combinations (e.g., various embodiments intersecting schemes), adaptations or changes. The elements in the claims will be interpreted broadly based on the language adopted in the claims, and are not limited to the examples described in this specification or during the implementation of this application, and the examples will be interpreted as non-exclusive. Therefore, this specification and examples are intended to be considered as examples only, and the true scope and spirit are indicated by the following claims and the full scope of their equivalents.

[0088] The above description is intended to be illustrative rather than restrictive. For example, the above examples (or one or more of them) can be used in combination with each other. For example, those of ordinary skill in the art can use other embodiments when reading the above description. In addition, in the above-mentioned specific embodiments, various features can be grouped together to simplify the present invention. This should not be interpreted as a feature of an invention that is not claimed for protection being necessary for any claim. On the contrary, the subject matter of the present invention may be less than all the features of the embodiments of a specific invention. Thus, the following claims are incorporated into the specific embodiments as examples or embodiments, wherein each claim is independently used as a separate embodiment, and it is considered that these embodiments can be combined with each other in various combinations or arrangements. The scope of the present invention should be determined with reference to the full scope of the equivalent forms of the attached claims and these claims.

Claims

1. A numerical simulation method for rock acoustic emission, It is characterized in that The method comprises: Obtaining node coordinate information of a damaged unit and the time when a damage variable of the damaged unit is generated, wherein the damage variable is stiffness degradation, and the stiffness degradation is obtained according to a stress change in the damaged unit during a simulation process; Determine the position information of the damaged unit according to the node coordinate information of the damaged unit; Each damaged unit is regarded as an acoustic emission event, and according to the time when the damaged unit is damaged, the statistics of acoustic emission events at different times are realized; The energy dissipated per unit volume of the damaged unit during the simulation is taken as the energy of the acoustic emission event; According to the number of damaged units and the number of damaged units generated at different times, the curve of acoustic emission events changing with time is obtained; Obtaining an acoustic emission localization map according to the position information of the damage unit, wherein one point in the acoustic emission localization map represents one acoustic emission event, and the size of the point is determined according to the energy of the corresponding acoustic emission event; The step of obtaining the node coordinate information of the damaged unit and the time when the damage variable of the damaged unit is generated includes: Establish damage variables, and obtain stiffness changes by monitoring the stress and strain changes in a certain unit or region during the simulation process. Use stiffness degradation as the damage variable. During the numerical simulation of the model, traverse all units in the model, count all damaged units, and store the node coordinate information of the unit and the time when the damage variable begins to be generated. The step of obtaining an acoustic emission localization map according to the position information of the damaged unit, wherein a point in the acoustic emission localization map represents an acoustic emission event, and determining the size of the point according to the energy of the corresponding acoustic emission event, comprises: By extracting all the damaged unit information in the storage file, the number of acoustic emission events is obtained, the number of damaged units generated at different times is counted, the curve of the number of acoustic emission events changing with time is obtained, the position information of the damaged unit is extracted, and the acoustic emission positioning map is obtained. In the acoustic emission positioning map, one point is used to represent one acoustic emission event. The energy dissipated in the unit volume of the stored damaged unit is further extracted, and the energy value is used as the size of the event point in the acoustic emission positioning map to intuitively represent the energy level of the acoustic emission event point.

2. The method according to claim 1, It is characterized in that The energy dissipated per unit volume of the damaged element during the simulation is calculated using the following formula: IN d =UU e ; Among them, U d represents the energy dissipated per unit volume of the damaged unit, U represents the total work done by the principal stress in the direction of the principal strain, Ue represents the releasable elastic strain energy stored per unit volume, ε i represents the work done by the i-th principal stress in the direction of the corresponding principal stress, σ i represents the i-th principal stress, represents the elastic strain corresponding to the i-th principal stress.

3. The method according to claim 1, It is characterized in that After taking the energy dissipated within the unit volume of the damaged unit during the simulation as the energy of the acoustic emission event, the method further comprises: Based on the set energy threshold, acoustic emission events with energy less than the energy threshold are eliminated.

4. The method according to claim 1, It is characterized in that The method further comprises: The fracture energy of the damaged unit is obtained, wherein the fracture energy includes tensile fracture energy and shear fracture energy, and the rupture type of the acoustic emission event is characterized by the ratio of the tensile fracture energy to the shear fracture energy.

5. The method according to claim 4, It is characterized in that In the acoustic emission localization map, the rupture types of different acoustic emission events are characterized by the color / shape of the points representing the acoustic emission events.

6. A device for numerical simulation of rock acoustic emission, It is characterized in that The device comprises: A data acquisition module is configured to acquire node coordinate information of a damaged unit and a time when a damage variable of the damaged unit is generated, wherein the damage variable is stiffness degradation, and the stiffness degradation is obtained according to a stress change in the damaged unit during a simulation process; A damage location module, configured to determine the location information of the damaged unit according to the node coordinate information of the damaged unit; The time statistics module is configured to take each damaged unit as an acoustic emission event, and realize the statistics of acoustic emission events at different times according to the time when the damaged unit is damaged; An energy calculation module is configured to use the energy dissipated within a unit volume of a damage unit during a simulation as the energy of an acoustic emission event; A curve determination module is configured to obtain a curve of acoustic emission events changing with time according to the number of damaged units and the number of damaged units generated at different times; A positioning map making module is configured to obtain an acoustic emission positioning map according to the position information of the damaged unit, wherein one point in the acoustic emission positioning map represents one acoustic emission event, and the size of the point is determined according to the energy of the corresponding acoustic emission event; The step of obtaining the node coordinate information of the damaged unit and the time when the damage variable of the damaged unit is generated includes: Establish damage variables, and obtain stiffness changes by monitoring the stress and strain changes in a certain unit or region during the simulation process. Use stiffness degradation as the damage variable. During the numerical simulation of the model, traverse all units in the model, count all damaged units, and store the node coordinate information of the unit and the time when the damage variable begins to be generated. The step of obtaining an acoustic emission localization map according to the position information of the damaged unit, wherein a point in the acoustic emission localization map represents an acoustic emission event, and determining the size of the point according to the energy of the corresponding acoustic emission event, comprises: By extracting all the damaged unit information in the storage file, the number of acoustic emission events is obtained, the number of damaged units generated at different times is counted, the curve of the number of acoustic emission events changing with time is obtained, the position information of the damaged unit is extracted, and the acoustic emission positioning map is obtained. In the acoustic emission positioning map, one point is used to represent one acoustic emission event. The energy dissipated in the unit volume of the stored damaged unit is further extracted, and the energy value is used as the size of the event point in the acoustic emission positioning map to intuitively represent the energy level of the acoustic emission event point.

7. The device according to claim 6, It is characterized in that The energy calculation module is further configured as follows: The energy dissipated per unit volume of the damaged element during the simulation is calculated using the following formula: IN d =UU e ; Among them, U d represents the energy dissipated per unit volume of the damaged unit, U represents the total work done by the principal stress in the direction of the principal strain, and U e represents the releasable elastic strain energy stored per unit volume, ε i represents the work done by the i-th principal stress in the direction of the corresponding principal stress, σ i represents the i-th principal stress, represents the elastic strain corresponding to the i-th principal stress.

8. The device according to claim 6, It is characterized in that The apparatus further comprises an energy screening module, wherein the energy screening module is further configured to: Based on the set energy threshold, acoustic emission events with energy less than the energy threshold are eliminated.

9. The device according to claim 8, It is characterized in that The device further includes a type determination module, and the type determination module is further configured to: The fracture energy of the damaged unit is obtained, wherein the fracture energy includes tensile fracture energy and shear fracture energy, and the rupture type of the acoustic emission event is characterized by the ratio of the tensile fracture energy to the shear fracture energy. 10 . A non-transitory computer-readable storage medium storing instructions, which, when executed by a processor, executes the method according to claim 1 .

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