Rock burst risk dynamic evaluation method and system based on principal stress increment difference

Abstract

This invention provides a method and system for dynamic assessment of rockburst risk based on principal stress increment difference, relating to the field of rockburst prevention and control technology. The method includes: determining the area to be assessed; collecting principal stress data of the surrounding rock within the area; calculating the principal stress increment and principal stress increment difference of the surrounding rock within the area; determining the response relationship between the principal stress increment difference and rockburst hazard, obtaining an evaluation criterion for the dynamic change of rockburst risk; and evaluating the dynamic change of rockburst risk in the area to be assessed according to the evaluation criterion. This invention can provide new analytical methods and indicators for rockburst disaster risk assessment in the mining field, playing a positive role in improving the accuracy of rockburst risk assessment in mining faces and the precise prevention and control of rockbursts.

Description

Technical Field

[0001] This invention relates to the field of rockburst prevention and control technology, and in particular to a method and system for dynamic evaluation of rockburst risk based on principal stress increment difference. Background Technology

[0002] Rockbursts are dynamic hazards during coal mining, severely impacting the safe extraction of coal resources. With the increasing depth and intensity of coal mining, rockbursts are becoming increasingly severe. Clearly understanding the dynamic changes in rockburst risk during underground coal mine operations is crucial for ensuring miners' safety and minimizing property damage.

[0003] Concentrated loads on coal and rock masses are a necessary condition for rockburst occurrence. Currently, indicators used to analyze the dynamic changes in rockburst risk are mostly stress intensity and stress gradient, and these have yielded many beneficial results. However, according to strength criteria, rock failure depends not only on stress magnitude and stress concentration, but also on the dynamic changes in the ultimate load that coal and rock can withstand during stress increases and decreases. The increment and difference of the principal stresses in each direction during these dynamic changes have a significant impact on rockburst failure. Therefore, relying solely on the stress concentration of the surrounding rock to assess rockburst risk cannot fully correspond to the actual rockburst occurrence during coal mine working face production. Furthermore, under the influence of geological and mining technology conditions, dynamic changes in the principal stresses of the surrounding rock are inevitable during working face mining. Therefore, it is necessary to further explore the dimensions of the increment and difference of the principal stresses in the surrounding rock. Summary of the Invention

[0004] This invention provides a dynamic evaluation method and system for rockburst risk based on principal stress increment difference, which solves the problem that the results of evaluating rockburst risk based solely on the degree of stress concentration in the surrounding rock in the prior art cannot fully correspond to the actual occurrence of rockbursts in the coal mine working face.

[0005] To achieve the aforementioned objectives, the present invention provides the following technical solution: A dynamic assessment method for rockburst risk based on principal stress increment difference, characterized in that the steps include:

[0006] S1. Determine the area to be evaluated;

[0007] S2. Collect principal stress data of the surrounding rock in the area to be evaluated;

[0008] S3. Calculate the principal stress increment and principal stress increment difference of the surrounding rock in the area to be evaluated;

[0009] S4. Determine the relationship between the principal stress increment difference and the response of rockburst hazard to obtain the evaluation criteria for the dynamic change of rockburst risk;

[0010] S5. Evaluate the dynamic changes in rockburst risk in the area to be evaluated based on the evaluation criteria for dynamic changes in rockburst risk.

[0011] Preferably, in step S1, determining the region to be evaluated includes:

[0012] Identify the regions affected by dynamic stress changes and define these regions as the areas to be evaluated.

[0013] Among them, the area affected by dynamic stress changes is the absolute position, or the relative position of the preset reference point.

[0014] Preferably, in step S2, the principal stress data of the surrounding rock in the area to be evaluated are collected, including:

[0015] The maximum and minimum principal stress data of the area to be evaluated are collected through on-site monitoring, laboratory experiments, or numerical simulation.

[0016] Preferably, in step S3, calculating the principal stress increment and principal stress increment difference of the surrounding rock in the region to be evaluated includes:

[0017] Obtain the principal stress increment, which is the difference between the principal stress after dynamic change and before dynamic change. The difference can be positive or negative.

[0018] The maximum principal stress increment F is calculated according to the following formula (1):

[0019] F=σ'1-σ1 (1)

[0020] The minimum principal stress increment f is calculated according to the following formula (2):

[0021] f=σ'3-σ3 (2)

[0022] Wherein, σ1 is the maximum principal stress before the dynamic change of the surrounding rock stress, σ'1 is the maximum principal stress after the dynamic change of the surrounding rock stress, σ3 is the maximum principal stress before the dynamic change of the surrounding rock stress, and σ'3 is the maximum principal stress after the dynamic change of the surrounding rock stress.

[0023] The principal stress increment difference Δ is the difference between the maximum principal stress increment F and the minimum principal stress increment f. The principal stress increment difference Δ is calculated according to the following formula (3):

[0024] Δ=Ff (3).

[0025] Preferably, in step S4, determining the relationship between the principal stress increment difference and the response to rockburst hazard includes:

[0026] Based on the principal stress increment difference Δ, and combined with the geometric relationship between the strength curve and the stress Mohr circle in the Mohr-Coulomb criterion, the criterion for preventing rockburst after dynamic stress change is that the radius R of the Mohr circle needs to be less than the perpendicular distance L from the center of the Mohr circle to the strength curve. The relationship of the principal stress increment difference Δ for preventing rockburst is shown in the following formula (4):

[0027]

[0028] Based on the relationship between the principal stress increment difference Δ and the rockburst hazard, a critical principal stress increment difference Δ exists. limit , When the principal stress increment difference reaches the critical principal stress increment difference Δ limit At this time, a rockburst will occur;

[0029] When the principal stress increment difference is less than the critical principal stress increment difference, the risk of rockburst will change dynamically with the value of the principal stress increment difference. The closer the principal stress increment difference is to the critical value for rockburst, the more likely rockburst will occur.

[0030] Preferably, in step S4, the evaluation criteria for obtaining the dynamic changes in rockburst risk include:

[0031] Based on the relationship between the principal stress increment difference and the response to rockburst hazard, an evaluation criterion for the dynamic change of rockburst risk is established; the evaluation criterion for the dynamic change of rockburst risk includes:

[0032] When the principal stress increment difference decreases, the probability of rockburst decreases, and the risk of rockburst decreases.

[0033] An increase in the principal stress increment difference increases the likelihood of rockburst, thus increasing the risk of rockburst.

[0034] Preferably, in step S5, the dynamic changes in rockburst risk in the area to be evaluated are assessed according to the evaluation criteria for dynamic changes in rockburst risk, including:

[0035] Based on the evaluation criteria for dynamic changes in rockburst risk, the increase or decrease of the difference in principal stress increments in the surrounding rock within the evaluation area before and after dynamic stress changes is compared. If the difference in principal stress increments increases after dynamic stress changes, it indicates that the risk of rockburst in the evaluation area has increased; if the difference in principal stress increments decreases after dynamic stress changes, it indicates that the risk of rockburst in the evaluation area has decreased.

[0036] A dynamic assessment system for rockburst risk based on principal stress increment difference, the system being used in the aforementioned dynamic assessment method for rockburst risk based on principal stress increment difference, the system comprising:

[0037] The region selection module is used to determine the region to be evaluated;

[0038] The data acquisition module is used to collect the principal stress data of the surrounding rock in the area to be evaluated.

[0039] The incremental difference calculation module is used to calculate the principal stress increment and principal stress increment difference of the surrounding rock in the region to be evaluated;

[0040] The evaluation criteria establishment module is used to determine the response relationship between the principal stress increment difference and the rockburst hazard, and to obtain the evaluation criteria for the dynamic change of rockburst risk.

[0041] The evaluation module is used to evaluate the dynamic changes of rockburst risk in the area to be evaluated based on the evaluation criteria for dynamic changes in rockburst risk.

[0042] Preferably, the region selection module is used to acquire the region affected by dynamic stress changes, and to determine the region affected by dynamic stress changes as the region to be evaluated;

[0043] The region affected by dynamic stress changes is either an absolute position or a relative position of a preset reference point.

[0044] Preferably, the data acquisition module is used to acquire the maximum principal stress data and minimum principal stress data of the area to be evaluated through on-site monitoring, laboratory experiments, or numerical simulation.

[0045] On the one hand, an electronic device is provided, comprising a processor and a memory, wherein the memory stores at least one instruction, which is loaded and executed by the processor to implement the above-mentioned dynamic assessment method for rockburst risk based on principal stress increment difference.

[0046] On the one hand, a computer-readable storage medium is provided, wherein at least one instruction is stored in the storage medium, and the at least one instruction is loaded and executed by a processor to implement the above-mentioned dynamic assessment method for rockburst risk based on principal stress increment difference.

[0047] The above technical solution has at least the following advantages compared with the existing technology:

[0048] The above-described scheme, provided by this invention, is a method for evaluating the dynamic changes in rockburst risk using the difference in principal stress increments. It uses the principal stress data of coal and rock collected during the dynamic stress change process as raw data, and proposes methods for calculating the principal stress increments and the difference in principal stress increments. The dynamic changes in rockburst risk in the area to be evaluated are then assessed using the difference in principal stress increments. This method improves the accuracy of evaluating the dynamic changes in rockburst risk during mining operations and helps improve the effectiveness of mining enterprises in preventing rockburst disasters. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This is a schematic diagram of the dynamic assessment method for rockburst risk based on principal stress increment difference provided in an embodiment of the present invention;

[0051] Figure 2 This is a schematic diagram of the numerical simulation model provided in an embodiment of the present invention;

[0052] Figure 3 This is a graph of the principal stresses in the surrounding rock of the evaluation area provided in an embodiment of the present invention.

[0053] Figure 4 This is a curve showing the maximum principal stress increment in the area to be evaluated during the working face mining process, provided in an embodiment of the present invention.

[0054] Figure 5 This is a minimum principal stress increment curve of the area to be evaluated during the working face mining process provided in this embodiment of the invention;

[0055] Figure 6 These are the dynamic change curves of the principal stress increment difference in the evaluation area during the working face mining process and the rockburst risk assessment result diagram provided in this embodiment of the invention;

[0056] Figure 7 This is a block diagram of a dynamic assessment system for rockburst risk based on principal stress increment difference provided in an embodiment of the present invention;

[0057] Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0059] This invention addresses the problem that existing technologies that rely solely on the stress concentration of surrounding rock to assess rockburst risk cannot fully reflect the actual occurrence of rockbursts during coal mine operations. It provides a dynamic assessment method and system for rockburst risk based on principal stress increment differences. By collecting principal stress data in all directions of coal and rock, and calculating the principal stress increments and increment differences, the system accurately assesses the dynamic changes in rockburst risk during stress dynamic changes. This improves the accuracy of assessing the dynamic changes in rockburst risk during mining operations and helps enhance the effectiveness of mine enterprises in preventing rockburst disasters.

[0060] like Figure 1 As shown, this embodiment of the invention provides a dynamic assessment method for rockburst risk based on the principal stress increment difference, which can be implemented by electronic equipment. Figure 1 The flowchart shown is for a dynamic assessment method of rockburst risk based on principal stress increment difference. The processing flow of this method may include the following steps:

[0061] S101. Determine the area to be evaluated;

[0062] In one feasible implementation, step S101, determining the region to be evaluated, includes:

[0063] Identify the regions affected by dynamic stress changes and define these regions as the areas to be evaluated.

[0064] Among them, the area affected by dynamic stress changes is the absolute position, or the relative position of the preset reference point.

[0065] S102. Collect principal stress data of the surrounding rock in the area to be evaluated;

[0066] In one feasible implementation, step S102 involves collecting principal stress data of the surrounding rock in the area to be evaluated, including:

[0067] The maximum and minimum principal stress data of the area to be evaluated are collected through on-site monitoring, laboratory experiments, or numerical simulation.

[0068] In one feasible implementation, on-site monitoring can be carried out using on-site monitoring equipment such as strain gauges and borehole stress gauges;

[0069] Laboratory experiments can be conducted using a sample loading system;

[0070] Numerical simulation can use computer simulation software to simulate and calculate principal stresses and collect data through numerical simulation methods such as finite element analysis or discrete element analysis.

[0071] S103. Calculate the principal stress increment and principal stress increment difference of the surrounding rock in the area to be evaluated;

[0072] In one feasible implementation, step S103, calculating the principal stress increment and principal stress increment difference of the surrounding rock in the region to be evaluated, includes:

[0073] Obtain the principal stress increment, which is the difference between the principal stress after dynamic change and before dynamic change. The difference can be positive or negative.

[0074] The maximum principal stress increment F is calculated according to the following formula (1):

[0075] F=σ'1-σ1 (1)

[0076] The minimum principal stress increment f is calculated according to the following formula (2):

[0077] f=σ'3-σ3 (2)

[0078] Wherein, σ1 is the maximum principal stress before the dynamic change of the surrounding rock stress, σ'1 is the maximum principal stress after the dynamic change of the surrounding rock stress, σ3 is the maximum principal stress before the dynamic change of the surrounding rock stress, and σ'3 is the maximum principal stress after the dynamic change of the surrounding rock stress.

[0079] The principal stress increment difference Δ is the difference between the maximum principal stress increment F and the minimum principal stress increment f. The principal stress increment difference Δ is calculated according to the following formula (3):

[0080] Δ=Ff (3).

[0081] S104. Determine the relationship between the principal stress increment difference and the response of rockburst hazard to obtain the evaluation criteria for the dynamic change of rockburst risk.

[0082] In one feasible implementation, step S104, determining the response relationship between the principal stress increment difference and the rockburst hazard, includes:

[0083] According to the geometric relationship between the strength curve and the stress Mohr circle in the Mohr-Coulomb criterion, the criterion for the surrounding rock not to experience rockburst after dynamic stress changes is that the radius R of the Mohr circle needs to be less than the perpendicular distance L from the center of the Mohr circle to the strength curve, as shown in the following formula.

[0084] R < L

[0085] The calculation methods for R and L are shown below;

[0086]

[0087]

[0088] Where c is the cohesive force. The internal friction angle, both can be obtained through experimental testing;

[0089] Based on the principal stress increment difference Δ, and combined with the relevant formulas based on the Mohr-Coulomb criterion, the relationship of the principal stress increment difference Δ without rockburst is obtained as shown in the following formula (4):

[0090]

[0091] Based on the relationship between the principal stress increment difference Δ and the rockburst hazard, a critical principal stress increment difference Δ exists. limit , When the principal stress increment difference reaches the critical principal stress increment difference Δ limit At this time, a rockburst will occur;

[0092] When the principal stress increment difference is less than the critical principal stress increment difference, the risk of rockburst will change dynamically with the value of the principal stress increment difference. The closer the principal stress increment difference is to the critical value for rockburst, the more likely rockburst will occur.

[0093] In one feasible implementation, step S104, obtaining the evaluation criteria for the dynamic changes in rockburst risk, includes:

[0094] Based on the relationship between the principal stress increment difference and the response to rockburst hazard, an evaluation criterion for the dynamic change of rockburst risk is established; the evaluation criterion for the dynamic change of rockburst risk includes:

[0095] When the principal stress increment difference decreases, the probability of rockburst decreases, and the risk of rockburst decreases.

[0096] An increase in the principal stress increment difference increases the likelihood of rockburst, thus increasing the risk of rockburst.

[0097] S105. Based on the evaluation criteria for dynamic changes in rockburst risk, evaluate the dynamic changes in rockburst risk in the area to be evaluated.

[0098] In one feasible implementation, step S105 involves evaluating the dynamic changes in rockburst risk in the area to be evaluated based on the evaluation criteria for dynamic changes in rockburst risk, including:

[0099] Based on the evaluation criteria for dynamic changes in rockburst risk, the increase or decrease of the difference in principal stress increments in the surrounding rock within the evaluation area before and after dynamic stress changes is compared. If the difference in principal stress increments increases after dynamic stress changes, it indicates that the risk of rockburst in the evaluation area has increased; if the difference in principal stress increments decreases after dynamic stress changes, it indicates that the risk of rockburst in the evaluation area has decreased.

[0100] The method of this embodiment will be further explained below in conjunction with specific application scenarios:

[0101] This case study uses the LW203 working face in a rockburst-prone mine as an example. A numerical simulation model of the working face is established using FLAC3D software. The mining process of the LW203 working face is simulated in FLAC3D software according to the actual excavation steps. The principal stresses of the surrounding rock in the area to be evaluated during the mining process are collected, and the difference in principal stress increments is calculated to evaluate the dynamic changes in rockburst risk. The details are as follows:

[0102] First, the area to be evaluated was determined to be the surrounding rock 10-20m in front of the LW203 working face;

[0103] A numerical simulation model of the target mine LW203 was established. Following the actual excavation steps, the mining process of the LW203 working face was simulated in FLAC3D numerical simulation software. The principal stresses of the surrounding rock in the evaluation area were collected during the mining process. Figure 2 It is a simulation numerical model. Figure 3 This is a graph showing the maximum and minimum principal stresses of the surrounding rock in the area to be evaluated during the mining process. Figure 3 (a) is a graph showing the maximum and minimum principal stresses in the area to be evaluated during the mining process from 40 to 270 m in the working face. Figure 3 (b) is a graph showing the maximum and minimum principal stresses in the area to be evaluated during the mining process from 310 to 550 m.

[0104] Calculate the increment of surrounding rock and principal stress in the area to be evaluated during the mining process, where, Figure 4 It is the dynamic change curve of the maximum principal stress increment, where, Figure 4 (a) is a curve showing the maximum principal stress increment in the area to be evaluated during the mining process from 40 to 270 m in the working face. Figure 4 (b) is the maximum principal stress increment curve of the area to be evaluated during the mining process of the working face in the range of 310-550m; Figure 5 This is a dynamic curve showing the change in the minimum principal stress increment, where... Figure 5 (a) is a curve showing the minimum principal stress increment in the area to be evaluated during the mining process from 40 to 270 m in the working face. Figure 5 (b) is the minimum principal stress increment curve of the area to be evaluated during the mining process of the working face in the range of 310-550m.

[0105] Calculate the difference in principal stress increments between the surrounding rock and the principal rock mass in the evaluation area during the mining process. Based on the increase and decrease of the principal stress increment difference, evaluate the dynamic changes in the rockburst risk of the surrounding rock in the evaluation area during the mining process. The evaluation results are as follows: Figure 6 As shown;

[0106] Depend on Figure 6 It can be seen that as the working face continues to advance and is mined, the difference in principal stress increment of the surrounding rock 10-20m ahead of the LW203 working face gradually decreases, indicating that the risk of rockburst at the working face gradually decreases; as the working face continues to be mined, the difference in principal stress increment of the surrounding rock 10-20m ahead of the LW203 working face gradually increases, indicating that the risk of rockburst increases.

[0107] In this embodiment of the invention, a method for evaluating the dynamic changes in rockburst risk using the principal stress increment difference is proposed. This method uses the principal stress data collected during the dynamic changes of surrounding rock stress as the raw data, and proposes a method for calculating the principal stress increment and the principal stress increment difference. The dynamic changes in rockburst risk in the area to be evaluated are then assessed using the principal stress increment difference. This method improves the accuracy of evaluating the dynamic changes in rockburst risk during mining operations and helps improve the effectiveness of mining enterprises in preventing rockburst disasters.

[0108] Figure 7 This is a schematic diagram of a dynamic assessment system for rockburst risk based on principal stress increment difference according to the present invention. The system 200 is used in the above-mentioned dynamic assessment method for rockburst risk based on principal stress increment difference. The system 200 includes:

[0109] The region selection module 210 is used to determine the region to be evaluated;

[0110] Data acquisition module 220 is used to acquire principal stress data of the surrounding rock in the area to be evaluated;

[0111] The incremental difference calculation module 230 is used to calculate the principal stress increment and principal stress increment difference of the surrounding rock in the region to be evaluated.

[0112] The evaluation criterion establishment module 240 is used to determine the response relationship between the principal stress increment difference and the rockburst hazard, and to obtain the evaluation criteria for the dynamic change of rockburst risk.

[0113] The evaluation module 250 is used to evaluate the dynamic changes of rockburst risk in the area to be evaluated based on the evaluation criteria for dynamic changes in rockburst risk.

[0114] Preferably, the region selection module 210 is used to acquire the region affected by dynamic stress changes and determine the region affected by dynamic stress changes as the region to be evaluated.

[0115] The region affected by dynamic stress changes is either an absolute position or a relative position of a preset reference point.

[0116] Preferably, the data acquisition module 220 is used to acquire the maximum principal stress data and minimum principal stress data of the area to be evaluated through on-site monitoring, laboratory experiments or numerical simulation.

[0117] Preferably, in step S3, calculating the principal stress increment and principal stress increment difference of the surrounding rock in the region to be evaluated includes:

[0118] Obtain the principal stress increment, which is the difference between the principal stress after dynamic change and before dynamic change. The difference can be positive or negative.

[0119] The maximum principal stress increment F is calculated according to the following formula (1):

[0120] F=σ'1-σ1 (1)

[0121] The minimum principal stress increment f is calculated according to the following formula (2):

[0122] f=σ'3-σ3 (2)

[0123] Wherein, σ1 is the maximum principal stress before the dynamic change of the surrounding rock stress, σ'1 is the maximum principal stress after the dynamic change of the surrounding rock stress, σ3 is the maximum principal stress before the dynamic change of the surrounding rock stress, and σ'3 is the maximum principal stress after the dynamic change of the surrounding rock stress.

[0124] The principal stress increment difference Δ is the difference between the maximum principal stress increment F and the minimum principal stress increment f. The principal stress increment difference Δ is calculated according to the following formula (3):

[0125] Δ=Ff (3).

[0126] Preferably, in step S4, determining the relationship between the principal stress increment difference and the response to rockburst hazard includes:

[0127] Based on the principal stress increment difference Δ, and combined with the geometric relationship between the strength curve and the stress Mohr circle in the Mohr-Coulomb criterion, the criterion for preventing rockburst after dynamic stress change is that the radius R of the Mohr circle needs to be less than the perpendicular distance L from the center of the Mohr circle to the strength curve. The relationship of the principal stress increment difference Δ for preventing rockburst is shown in the following formula (4):

[0128]

[0129] Based on the relationship between the principal stress increment difference Δ and the rockburst hazard, a critical principal stress increment difference Δ exists. limit , When the principal stress increment difference reaches the critical principal stress increment difference Δ limit At this time, a rockburst will occur;

[0130] When the principal stress increment difference is less than the critical principal stress increment difference, the risk of rockburst will change dynamically with the value of the principal stress increment difference. The closer the principal stress increment difference is to the critical value for rockburst, the more likely rockburst will occur.

[0131] Preferably, in step S4, the evaluation criteria for obtaining the dynamic changes in rockburst risk include:

[0132] Based on the relationship between the principal stress increment difference and the response to rockburst hazard, an evaluation criterion for the dynamic change of rockburst risk is established; the evaluation criterion for the dynamic change of rockburst risk includes:

[0133] When the principal stress increment difference decreases, the probability of rockburst decreases, and the risk of rockburst decreases.

[0134] An increase in the principal stress increment difference increases the likelihood of rockburst, thus increasing the risk of rockburst.

[0135] Preferably, in step S5, the dynamic changes in rockburst risk in the area to be evaluated are assessed according to the evaluation criteria for dynamic changes in rockburst risk, including:

[0136] Based on the evaluation criteria for dynamic changes in rockburst risk, the increase or decrease of the difference in principal stress increments in the surrounding rock within the evaluation area before and after dynamic stress changes is compared. If the difference in principal stress increments increases after dynamic stress changes, it indicates that the risk of rockburst in the evaluation area has increased; if the difference in principal stress increments decreases after dynamic stress changes, it indicates that the risk of rockburst in the evaluation area has decreased.

[0137] In this embodiment of the invention, a method for evaluating the dynamic changes in rockburst risk using the principal stress increment difference is proposed. This method uses the principal stress data collected during the dynamic changes of surrounding rock stress as the raw data, and proposes a method for calculating the principal stress increment and the principal stress increment difference. The dynamic changes in rockburst risk in the area to be evaluated are then assessed using the principal stress increment difference. This method improves the accuracy of evaluating the dynamic changes in rockburst risk during mining operations and helps improve the effectiveness of mining enterprises in preventing rockburst disasters.

[0138] Figure 8 This is a schematic diagram of the structure of an electronic device 300 provided in an embodiment of the present invention. The electronic device 300 can vary considerably due to differences in configuration or performance. It may include one or more central processing units (CPUs) 301 and one or more memories 302. The memories 302 store at least one instruction, which is loaded and executed by the processors 301 to implement the steps of the following dynamic assessment method for rockburst risk based on principal stress increment differences:

[0139] S1. Determine the area to be evaluated;

[0140] S2. Collect principal stress data of the surrounding rock in the area to be evaluated;

[0141] S3. Calculate the principal stress increment and principal stress increment difference of the surrounding rock in the area to be evaluated;

[0142] S4. Determine the relationship between the principal stress increment difference and the response of rockburst hazard to obtain the evaluation criteria for the dynamic change of rockburst risk;

[0143] S5. Evaluate the dynamic changes in rockburst risk in the area to be evaluated based on the evaluation criteria for dynamic changes in rockburst risk.

[0144] In an exemplary embodiment, a computer-readable storage medium is also provided, such as a memory including instructions that can be executed by a processor in a terminal to complete the aforementioned dynamic assessment method for rockburst risk based on principal stress increment differences. For example, the computer-readable storage medium may be a ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, or optical data storage device.

[0145] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

Claims

1. A dynamic evaluation method of rock burst risk based on principal stress increment difference, characterized in that, The method steps include: S1. Determine the area to be evaluated; S2. Collect principal stress data of the surrounding rock in the area to be evaluated; S3. Calculate the principal stress increment and principal stress increment difference of the surrounding rock in the region to be evaluated; S3 includes: Obtain the principal stress increment, which is the difference between the principal stress after dynamic change and before dynamic change, and the difference can be positive or negative. The maximum principal stress increment is calculated according to the following formula (1). F : （1） The minimum principal stress increment is calculated according to the following equation (2) f : （2） in, It is the maximum principal stress before the dynamic change of the surrounding rock stress. It is the maximum principal stress after the dynamic change of the surrounding rock stress. It is the minimum principal stress before the dynamic change of the surrounding rock stress. It is the minimum principal stress after the dynamic change of the surrounding rock stress; Principal stress increment difference Maximum principal stress increment F With minimum principal stress increment f The difference is calculated according to the following formula (3) to determine the principal stress increment difference. : （3）； S4. Determine the relationship between the principal stress increment difference and the response to rockburst hazard to obtain the evaluation criteria for the dynamic change of rockburst risk; S4 includes: Based on the principal stress increment difference Combining the geometric relationship between the strength curve and the Mohr's circle in the Mohr-Coulomb criterion, the criterion for preventing rockburst in the surrounding rock after dynamic stress changes is the radius of the Mohr's circle. R It needs to be less than the perpendicular distance from the center of the Mohr circle to the intensity curve. L The principal stress increment difference without rockburst is obtained. The relationship is shown in the following formula (4): （4） wherein, c represents cohesion, represents internal friction angle; According to the principal stress increment difference The relationship with the rock burst danger, there is a critical principal stress increment difference , When the principal stress increment difference reaches the critical principal stress increment difference , at this time the rock burst will occur; When the principal stress increment difference is less than the critical principal stress increment difference, the risk of rockburst will change dynamically with the value of the principal stress increment difference. The closer the principal stress increment difference is to the critical value for rockburst, the easier it is for rockburst to occur. S5. Evaluate the dynamic changes of rockburst risk in the area to be evaluated based on the evaluation criteria for dynamic changes in rockburst risk.

2. The method of claim 1, wherein, In step S1, determining the region to be evaluated includes: The region affected by dynamic stress changes is identified, and the region affected by dynamic stress changes is determined as the region to be evaluated. The region affected by dynamic stress changes is either an absolute position or a relative position of a preset reference point.

3. The method of claim 2, wherein, In step S2, the principal stress data of the surrounding rock in the area to be evaluated are collected, including: The maximum and minimum principal stress data of the area to be evaluated are collected through on-site monitoring, laboratory experiments, or numerical simulation.

4. The method of claim 3, wherein, In step S4, the evaluation criteria for the dynamic changes in rockburst risk are obtained, including: Based on the relationship between the principal stress increment difference and the response to rockburst hazard, an evaluation criterion for the dynamic change of rockburst risk is established; the evaluation criterion for the dynamic change of rockburst risk includes: When the principal stress increment difference decreases, the probability of rockburst decreases, and the risk of rockburst decreases. An increase in the principal stress increment difference increases the likelihood of rockburst, thus increasing the risk of rockburst.

5. The method of claim 4, wherein, In step S5, the dynamic changes of rockburst risk in the area to be evaluated are assessed according to the evaluation criteria for dynamic changes in rockburst risk, including: Based on the evaluation criteria for dynamic changes in rockburst risk, the increase or decrease of the difference in principal stress increments in the surrounding rock within the evaluation area before and after the dynamic stress change is compared. If the difference in principal stress increments increases after the dynamic stress change, it indicates that the rockburst risk in the evaluation area has increased; if the difference in principal stress increments decreases after the dynamic stress change, it indicates that the rockburst risk in the evaluation area has decreased.

6. A rock burst risk dynamic evaluation system based on principal stress increment difference, characterized in that, The system is used in the dynamic assessment method for rockburst risk based on principal stress increment difference as described in any one of claims 1 to 5, and the system comprises: The region selection module is used to determine the region to be evaluated; The data acquisition module is used to collect the principal stress data of the surrounding rock in the area to be evaluated. The incremental difference calculation module is used to calculate the principal stress increment and principal stress increment difference of the surrounding rock in the region to be evaluated; The evaluation criteria establishment module is used to determine the response relationship between the principal stress increment difference and the rockburst hazard, and to obtain the evaluation criteria for the dynamic change of rockburst risk. The evaluation module is used to evaluate the dynamic changes of rockburst risk in the area to be evaluated based on the evaluation criteria for dynamic changes in rockburst risk.

7. The system of claim 6, wherein, The region selection module is used to acquire the region affected by dynamic stress changes and to determine the region affected by dynamic stress changes as the region to be evaluated. The region affected by dynamic stress changes is either an absolute position or a relative position of a preset reference point.

8. The system of claim 7, wherein, The data acquisition module is used to collect the maximum principal stress data and minimum principal stress data of the area to be evaluated through on-site monitoring, laboratory experiments or numerical simulation.

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