Rock burst prediction, prevention and control method

Abstract

The invention discloses a rockburst prediction method. The rockburst prediction method comprises the following steps: step 1, establishing a tunnel analysis model; secondly, stratum stress-strain space distribution and plastic zone space distribution before and after the cavern is excavated are obtained; step 3, if there is no plastic zone space, determining that there is no rock burst danger; if the plastic zone space exists, continuing the step 4; 4, the elastic stored energy Ee of the surrounding rock before excavation and the fracture energy consumption Wf of the surrounding rock after excavation are calculated; and 5, calculating a rockburst index Irb, and dividing rockburst grades. By adopting the prediction method, the elastic stored energy and fracture energy consumption of specific parts such as a tunnel vault, a haunch and a side wall can be quantitatively calculated, and the rock burst occurrence probability of the specific parts can be predicted through the ratio of the elastic stored energy to the fracture energy consumption.

Description

Technical Field

[0001] The invention belongs to the technical field of early warning and prevention of underground engineering disasters, and specifically relates to a rockburst prediction and prevention method. Background Art

[0002] Rockburst is the phenomenon of rock blocks ejected at high speed during underground cavern excavation. Since the surrounding rock has been in a high-stress environment for a long time, a large amount of elastic strain energy is stored. After the cavern is excavated, the elastic strain energy of the surrounding rock is violently released, causing rock blocks to eject at high speed, causing serious damage to construction personnel and equipment. With the development of resource and space utilization in the deep sea and deep earth, the frequency of rockbursts in high-stress environments is increasing, and the difficulty of construction is increasing day by day.

[0003] At present, the means and methods of rockburst prediction mainly include microseismic monitoring method and historical experience judgment method. These two methods have been applied to a certain extent in engineering practice, but the actual application effect is highly dependent on personal experience, and these two prediction methods do not explain the mechanical mechanism of rockburst.

[0004] The energy criterion based on strain energy theory can well explain the mechanical mechanism of rockburst and has great potential in rockburst prediction scenarios under complex geostress states. The energy criterion believes that a large amount of elastic strain energy is stored in the surrounding rock before the excavation of the cavern. With the excavation of the cavern, the radial stress of the cavern wall decreases, the tangential stress increases, the rock undergoes plastic deformation, the cracks open and expand, and finally the cracks penetrate, and the rock blocks are ejected at high speed. From the energy point of view, it is the process of converting the stored elastic strain energy into the energy consumption of crack cracking and expansion. If the stored elastic strain energy is much greater than the energy consumption of crack cracking and expansion, the excess energy will be converted into the kinetic energy of the rock blocks, causing the rock blocks to be ejected at high speed. Although the energy criterion can explain the occurrence mechanism of rockburst, in specific engineering practice, the energy consumption of crack cracking and expansion is difficult to quantify, and the stored strain energy is positively correlated with the volume, and the energy consumption of the crack is positively correlated with the crack area. The difference in the spatial scale of stored energy and consumed energy means that the energy criterion must have a scale effect. Due to the difficulty in quantifying energy and the influence of scale effect, the application of energy criterion in rockburst prediction is currently difficult. Summary of the invention

[0005] The purpose of the present invention is to provide a rockburst prediction and prevention method, which can quantitatively calculate the elastic energy storage and crack energy consumption of specific parts such as the tunnel vault, arch waist, side wall, etc. The ratio of elastic energy storage to crack energy consumption can be used to predict the probability of rockburst occurrence in specific parts and take corresponding measures.

[0006] The present invention adopts the following technical solution: a rockburst prediction method, comprising the following steps:

[0007] Step 1: Establish a tunnel analysis model:

[0008] A tunnel analysis model is established according to the buried depth, size and physical and mechanical parameters of the cavern to be excavated, and the physical and mechanical parameters of the stratum where the cavern is located. The tunnel analysis model is a rectangular parallelepiped composed of strata, and the cavern to be excavated is open at both ends along its long central axis. The ground stress determined by the geological survey report is the boundary condition of the tunnel analysis model.

[0009] Step 2: obtaining the spatial distribution of stratum stress and strain and the spatial distribution of plastic zone before and after the excavation of the cavern;

[0010] Step 3: If there is no plastic zone space, there is no risk of rock burst; if there is plastic zone space, proceed to step 4;

[0011] Step 4: Calculate the elastic energy storage E of the surrounding rock before excavation e The energy consumption of surrounding rock fracture after excavation W f :

[0012] Step 5: Calculate rockburst index I rb , and classify rock burst levels:

[0013]

[0014] Where: s To consider the correction factor of the size effect of stored energy and crack energy consumption, when the equivalent radius of the cavern is 4m to 8m, λ s =1; when the equivalent radius of the cavern is 8-13m, λ s =1.3; when the equivalent radius of the cavern is 13-21m, λ s =1.6;

[0015] According to the rockburst index I rb Classify rock burst levels.

[0016] Furthermore, the specific process of step 4 is as follows:

[0017] Step 4-1, in the rectangular parallelepiped of the tunnel analysis model in step 1, a cylindrical body is selected at the predicted location of the cavern rock burst as a local analysis model, and the volume of the local analysis model is V;

[0018] Step 4-2: Obtain the stress-strain distribution of the predicted rockburst location in the surrounding rock state distribution after the cavern excavation in step 2, extract the principal stress and principal strain values ​​of the predicted rockburst location, and calculate the elastic energy storage E before the cavern excavation. e ,as follows:

[0019]

[0020] Among them, σ1, σ2, and σ3 are the maximum principal stress, intermediate principal stress, and minimum principal stress of the predicted cavern rockburst location before excavation, respectively; ε1, ε2, and ε3 are the maximum principal strain, intermediate principal strain, and minimum principal strain of the predicted cavern rockburst location before excavation, respectively; V is the volume of the local analysis model;

[0021] Step 4-3: Calculate the fracture energy consumption W after excavation of the predicted rockburst location in the cavern f ,as follows:

[0022]

[0023] Where: r To consider the fracture energy dissipation correction factor of the surrounding rock grade, when the surrounding rock grade is II, λ r =0.85, when the surrounding rock grade is III r =0.9, when the surrounding rock grade is IV or V r =1.15; F is the correction factor used when the actual fracture type does not conform to the I-type crack, and F=0.75; N is the number of fracture surfaces, N=1; L, W, H are the length, width, and height of the local analysis model respectively; G f is the fracture energy of surrounding rock.

[0024] Furthermore, the specific process of step 2 is as follows: the physical and mechanical parameters of the cavern to be excavated are the same as those of the stratum, and the depth, size and physical and mechanical parameters of the cavern to be excavated P are determined by the following method: l And the physical and mechanical parameters P of the local formation l , the stress and strain spatial distribution of the stratum before excavation is obtained by the tunnel analysis model;

[0025] The depth and size of the cavern and the physical and mechanical parameters of the cavern after excavation, as well as the physical and mechanical parameters of the stratum where the cavern is located, are input into the tunnel analysis model to obtain the stress and strain spatial distribution of the stratum after the cavern is excavated; the physical and mechanical parameters of the cavern after excavation are 0;

[0026] According to the spatial distribution of stress and strain and the Mohr-Coulomb yield criterion, the spatial distribution of the plastic zone of the formation is determined.

[0027] Furthermore, when the length L, width W and height H of the local analysis model are 0.15 m, 0.15 m and 0.3 m respectively, the rockburst index I rb When it is less than 3.5, the possibility of rock burst is low; rock burst index I rb When it is between 3.5 and 4.5, a minor rock burst may occur; rock burst index I rb When it is between 4.5 and 6.5, moderate rock burst may occur; rock burst index I rb When it is greater than 6.5, severe rock burst may occur.

[0028] Furthermore, the surrounding rock fracture energy G is determined by splitting test. f ;

[0029] Obtain surrounding rock samples of the formation by drilling and coring;

[0030] The surrounding rock sample is made into a wedge-shaped split test block, the initial crack depth of the test block is a, the height of the test block is H, and the thickness of the test block is T;

[0031] The wedge-shaped splitting specimen is torn apart by a loading machine, and the splitting energy is calculated, such as Figure 3 As shown, the calculation formula is:

[0032]

[0033] Where: G f is the fracture energy of surrounding rock; ∫Pdδ is the work done by external force.

[0034] Furthermore, the physical and mechanical parameters of the formation are P l , the acquisition process is as follows:

[0035] Step 1-1, obtaining surrounding rock samples of the formation by coring through drilling;

[0036] Step 1-2: Determine the surrounding rock sample of the stratum in step 1-1 to obtain the physical and mechanical parameters P of the rock block. r ;

[0037] Step 1-3: The physical and mechanical parameters P of the rock block in step 1-2 are r Multiply by the rock mass scale effect parameter α r After that, the physical and mechanical parameters P of the formation are obtained. l ,as follows:

[0038] P l =α r P r

[0039] Where: For the elastic modulus α r = 0.5, for the cohesive internal friction angle α r =0.3, other physical and mechanical parameters α r =1.

[0040] Furthermore, the physical and mechanical parameters P of the rock block r Including the following: density of surrounding rock samples, elastic modulus and Poisson's ratio of surrounding rock samples, cohesion and internal friction angle of surrounding rock samples; the determination is as follows:

[0041] Determine the density of surrounding rock samples by water displacement method;

[0042] The elastic modulus and Poisson's ratio of the surrounding rock samples were determined by uniaxial compression test;

[0043] The cohesion and internal friction angle of the surrounding rock samples were determined by triaxial compression test.

[0044] The present invention also discloses a rockburst prevention and control method, including the above-mentioned rockburst prediction method, and further including step 6 after step 5, as follows:

[0045] Step 6. Develop corresponding disposal measures according to the rockburst level: adopt the original design when the possibility of rockburst is low; when a minor rockburst is likely to occur, adopt measures such as sprinkling water on the cave wall and adding a protective net in the rockburst area; when a moderate rockburst is likely to occur, adopt measures such as sprinkling water on the cave wall and adding a protective net in the rockburst area, and adopt radial drilling to unload and strengthen primary support; when a strong rockburst is likely to occur, adopt advanced drilling to unload and add energy-absorbing anchor rods on the basis of the above-mentioned rockburst prevention and control measures.

[0046] The beneficial effects of the present invention are as follows: by establishing a tunnel analysis model, the spatial distribution of stress and strain during tunnel excavation is calculated; at the same time, by adopting a local analysis model of a fixed size, the elastic energy storage and crack energy consumption of specific parts such as the arch crown, arch waist, side wall, etc. can be quantitatively calculated; and the probability and intensity of rock bursts at specific parts can be predicted through the ratio of elastic energy storage to crack energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 Schematic diagram of the tunnel analysis model.

[0048] Figure 2 Schematic diagram of the splitting test specimen.

[0049] Figure 3 Schematic diagram of the local analysis model for the predicted location of cavern rockburst.

[0050] Figure 4 Schematic diagram of prevention and control measures for moderate rock burst.

[0051] Figure 5 Schematic diagram of prevention and control measures for severe rock burst.

[0052] Among them: 1-cave; 2-stratum; 3-boundary conditions; 4-predicted rockburst location in the cavern; 5-radial drilling; 6-system anchor rod; 7-rockburst risk area; 8-primary lining; 9-energy-absorbing anchor rod; 10-advanced pilot hole. DETAILED DESCRIPTION

[0053] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0054] The present invention discloses a rockburst prediction method, which is characterized by comprising the following steps:

[0055] Step 1: Establish a tunnel analysis model:

[0056] According to the burial depth, size and physical and mechanical parameters of the cavern 1 to be excavated, as well as the physical and mechanical parameters of the stratum 2 where it is located, a tunnel analysis model is established using finite element analysis software. The tunnel analysis model is a rectangular parallelepiped composed of stratum 2, with the cavern 1 to be excavated open at both ends along its long central axis; the ground stress determined in the geological survey report is the boundary condition of the tunnel analysis model; the actual representative rock and soil body to be measured is subjected to the force of the surrounding rock and soil body, indicating the actual force environment of the rock and soil body; the ground stress obtained in the geological survey report is input as the boundary condition into the stratum edge of the tunnel analysis model. Figure 1 shown.

[0057] The minimum distance between the stratum edge and the cavern 1 is not less than three times the diameter of the excavated cavern 1;

[0058] Stress boundary conditions: Boundary conditions refer to the uniformly distributed pressure input at the boundary, which actually represents the force exerted on the rock and soil body to be tested by the surrounding rock and soil bodies, indicating the actual stress environment of the rock and soil body;

[0059] The minimum distance between the edge of the stratum and cavern 1 is not less than three times the diameter of cavern 1; the outer edge of the stratum refers to the four sides of the cuboid.

[0060] Step 2: Obtain the spatial distribution of stratum stress and strain and the spatial distribution of plastic zone before and after excavation of the cavern 1 to be excavated:

[0061] The cavern 1 to be excavated and the stratum 2 are both set as solid units. The physical and mechanical parameters of the cavern 1 to be excavated and the stratum 2 are the same. l And the physical and mechanical parameters P of the layer 2 l , the stress-strain spatial distribution of stratum 2 before excavation is obtained by the tunnel analysis model;

[0062] The buried depth, size and physical and mechanical parameters of the cavern 1 after excavation, as well as the physical and mechanical parameters of the stratum 2 where it is located, are input into the tunnel analysis model to obtain the stress and strain spatial distribution of the stratum after the excavation of the cavern 1; the physical and mechanical parameters of the cavern 1 after excavation are 0;

[0063] According to the spatial distribution of stress and strain, the spatial distribution of the plastic zone is determined based on the Mohr-Coulomb yield criterion;

[0064] Step 3: If there is no plastic zone space, there is no risk of rock burst; if there is plastic zone space, proceed to step 4;

[0065] Step 4: Calculate the elastic energy storage E of the surrounding rock before excavation e The energy consumption of surrounding rock fracture after excavation W f :

[0066] Step 4-1, determine the predicted rockburst location 4 of the cavern, generally select the side wall, arch waist and arch top for rockburst prediction, in the rectangular parallelepiped of the tunnel analysis model in step 1, select a cylindrical body at the predicted rockburst location 4 of the cavern as a local analysis model, and the volume of the local analysis model is V;

[0067] Step 4-2: In the surrounding rock state distribution after cavern excavation in step 2, the stress-strain distribution of cavern rockburst prediction location 4 is obtained, the principal stress and principal strain values ​​of cavern rockburst prediction location 4 are extracted, and the elastic energy storage E before cavern excavation is calculated. e ,like Figure 3 As shown below:

[0068]

[0069] Among them, σ1, σ2, and σ3 are the maximum principal stress, intermediate principal stress, and minimum principal stress of the predicted cavern rockburst location before excavation, ε1, ε2, and ε3 are the maximum principal strain, intermediate principal strain, and minimum principal strain of the predicted cavern rockburst location before excavation, V is the volume of the local analysis model; V = LWH, L, W, H are the length, width, and height of the local analysis model, respectively; G f is the fracture energy of the surrounding rock. Figure 4 As shown, the local analysis model is a column with a length of L = 0.15m, a width of W = 0.15m, and a height of H = 0.3m.

[0070] Step 4-3: Calculate the fracture energy consumption W after excavation of the predicted rockburst location 4 in the cavern f ,as follows:

[0071]

[0072] Where: r is the crack energy dissipation correction factor considering the surrounding rock grade. When the surrounding rock grade is II, r =0.85, when the surrounding rock grade is III r =0.9, when the surrounding rock grade is IV or V r =1.15; F is the correction coefficient used when the actual fracture type does not conform to the I-type crack, and F=0.75 is taken; N is the number of fracture surfaces, N=1; L, W, and H are the length, width, and height of the local analysis model, respectively. The length, width, and height of the local analysis model used are 0.15m, 0.15m, and 0.3m, respectively.

[0073] like Figure 2 As shown in the figure, the surrounding rock fracture energy G is determined by splitting test. f :

[0074] Obtain surrounding rock samples of formation 2 by coring through drilling;

[0075] The surrounding rock sample is made into a wedge-shaped split test block, the initial crack depth of the test block is a, the test block height is H, and the test block thickness is T;

[0076] The wedge-shaped splitting specimen is torn apart by a loading machine, and the splitting energy is calculated, such as Figure 3 As shown, the calculation formula is:

[0077]

[0078] Where: G f is the fracture energy of surrounding rock; ∫Pdδ is the work done by external force.

[0079] Step 5: Calculate rockburst index I rb , and classify rock burst levels

[0080]

[0081] Where: s To consider the correction factor of the size effect of stored energy and crack energy consumption, when the equivalent radius of the cavern is 4m to 8m, λ s =1; when the equivalent radius of the cavern is 8-13m, λ s =1.3; when the equivalent radius of the cavern is 13-21m, λ s =1.6;

[0082] According to the rockburst index I rb Classification of rock burst levels, rock burst index I rb When it is less than 3.5, the possibility of rock burst is low; rock burst index I rb When it is between 3.5 and 4.5, a minor rock burst may occur; rock burst index I rb When it is between 4.5 and 6.5, moderate rock burst may occur; rock burst index I rb When it is greater than 6.5, severe rock burst may occur.

[0083] The present invention also discloses a rockburst prevention and control method, including the above-mentioned rockburst prediction method, and further including step 6 after step 5, as follows: step 6, formulating corresponding disposal measures according to the rockburst level:

[0084] The original design is used when the possibility of rock burst is low.

[0085] When a minor rock burst is likely to occur, measures such as sprinkling water on the cave wall and adding protective nets should be adopted in the area where a minor rock burst may occur;

[0086] When medium rock burst may occur, watering the cave wall and adding protective nets are adopted in the area where medium rock burst may occur. In the rock burst risk area 7, multiple radial pressure relief boreholes 5 are drilled radially around the cave 1 to relieve the load and strengthen the primary support measures. The diameter of the radial boreholes 5 is 80-115mm, the length is 8-12m, and the spacing is 1.5-3m. Figure 4 shown.

[0087] When a strong rock burst may occur, a pilot tunnel 10 is longitudinally excavated in the original designed cavern and in the area close to the arch to relieve pressure; the diameter of the pilot tunnel 10 should not be greater than 3m, and it is excavated above the original designed cavern. Support operations can be carried out 12 hours after the stress of the pilot tunnel excavation is released; measures such as sprinkling water on the cavern wall and adding protective nets are adopted; radial drilling around the cavern 1 is used to unload the load and strengthen the initial support measures. The diameter of the radial drilling hole 5 is 80-115mm, the length is 8-12m, and the spacing is 1.5-3m. In the area where a strong rock burst may occur, energy-absorbing anchor rods 9 are added. The energy-absorbing anchor rod 9 is a high-elongation and high-resistance anchor rod such as a J-type anchor rod, a D-type anchor rod or an NPR anchor rod. Strong rock burst prevention and control such as Figure 5 shown.

Claims

1. A rockburst prediction method, characterized in that: The following steps are involved: Step 1: Establish a tunnel analysis model: A tunnel analysis model is established according to the buried depth of the cavern (1) to be excavated, the size of the cavern (1) to be excavated, the physical and mechanical parameters of the cavern (1) to be excavated, and the physical and mechanical parameters of the stratum (2) where the cavern (1) is located. The tunnel analysis model is a rectangular parallelepiped composed of the stratum (2), and the cavern (1) to be excavated is open at both ends along its long central axis. The ground stress determined by the geological survey report is the boundary condition (3) of the tunnel analysis model. Step 2: obtaining the spatial distribution of stratum stress and strain and the spatial distribution of plastic zone before and after the excavation of the cavern (1); Step 3: If there is no plastic zone space, there is no risk of rock burst; if there is plastic zone space, proceed to step 4; Step 4: Calculate the elastic energy storage E of the surrounding rock before excavation e The energy consumption of surrounding rock fracture after excavation W f : Step 5: Calculate rockburst index I rb , and classify rock burst levels: Where: s To consider the correction factor of the size effect of stored energy and crack energy consumption, when the equivalent radius of the cavern is 4m to 8m, λ s =1; when the equivalent radius of the cavern is 8-13m, λ s =1.3; when the equivalent radius of the cavern is 13-21m, λ s =1.6; According to the rockburst index I rb Classify rock burst levels.

2. A rockburst prediction method according to claim 1, characterized in that: The specific process of step 4 is as follows: Step 4-1, in the rectangular parallelepiped of the tunnel analysis model in step 1, a cylindrical body is selected at the cavern rockburst prediction location (4) as a local analysis model, and the volume of the local analysis model is V; Step 4-2, in the surrounding rock field distribution after the cavern excavation in step 2, the stress and strain distribution of the rockburst prediction location (4) is obtained, the principal stress and principal strain values ​​of the rockburst prediction location (4) are extracted, and the elastic energy storage E before the cavern (1) is calculated. e ,as follows: Wherein, σ1, σ2, and σ3 are the maximum principal stress, intermediate principal stress, and minimum principal stress of the predicted cavern rockburst location (4) before excavation, respectively; ε1, ε2, and ε3 are the maximum principal strain, intermediate principal strain, and minimum principal strain of the predicted cavern rockburst location (4) before excavation, respectively; V is the volume of the local analysis model; Step 4-3: Calculate the fracture energy consumption W of the predicted rockburst location (4) after excavation f ,as follows: Where: r To consider the fracture energy dissipation correction factor of the surrounding rock grade, when the surrounding rock grade is II, λ r =0.85, when the surrounding rock grade is III r =0.9, when the surrounding rock grade is IV or V r =1.15; F is the correction factor used when the actual fracture type does not conform to the I-type crack, and F=0.75; N is the number of fracture surfaces, N=1; L, W, H are the length, width, and height of the local analysis model respectively; G f is the fracture energy of surrounding rock.

3. A rockburst prediction method according to claim 2, characterized in that: The specific process of step 2 is as follows: the physical and mechanical parameters of the cavern (1) to be excavated and the stratum (2) are the same, and the depth, size and physical and mechanical parameters of the cavern (1) to be excavated are calculated. l and the physical and mechanical parameters P of the local stratum (2) l , obtaining the stress-strain spatial distribution of the stratum (2) before excavation from the tunnel analysis model; The buried depth and size of the cavern (1), the physical and mechanical parameters of the cavern (1) after excavation, and the physical and mechanical parameters of the stratum (2) where the cavern (1) is located are input into the tunnel analysis model to obtain the stress and strain spatial distribution of the stratum after the cavern (1) is excavated; the physical and mechanical parameters of the cavern (1) after excavation are 0; Determine the spatial distribution of the plastic zone.

4. A rockburst prediction method according to claim 3, characterized in that: In step 5, when the length L, width W and height H of the local analysis model are 0.15 m, 0.15 m and 0.3 m respectively, the rockburst index I rb When it is less than 3.5, the possibility of rock burst is low; rock burst index I rb When it is between 3.5 and 4.5, a minor rock burst may occur; rock burst index I rb When it is between 4.5 and 6.5, moderate rock burst may occur; rock burst index I rb When it is greater than 6.5, severe rock burst may occur.

5. A rockburst prediction method according to claim 4, characterized in that: Determination of surrounding rock fracture energy G by splitting test f ; Obtaining surrounding rock samples of the formation (2) by coring the borehole; The surrounding rock sample is made into a wedge-shaped split test block, the initial crack depth of the test block is a, the height of the test block is H, and the thickness of the test block is T; The wedge-shaped splitting specimen was torn apart by a loading machine, and the splitting energy was calculated, as shown in Figure 3. The calculation formula is: Where: G f is the fracture energy of surrounding rock; ∫Pdδ is the work done by external force.

6. A rockburst prediction method according to claim 4, characterized in that: The physical and mechanical parameters of the formation (2) are P l , the acquisition process is as follows: Step 1-1, obtaining surrounding rock samples of the formation (2) by coring through drilling; Step 1-2: Determine the surrounding rock sample of the stratum (2) in step 1-1 to obtain the physical and mechanical parameters P of the rock block. r ; Step 1-3: The physical and mechanical parameters P of the rock block in step 1-2 are r Multiply by the rock mass scale effect parameter α r After that, the physical and mechanical parameters P of the formation are obtained. l ,as follows: P l =α r P r Where: For the elastic modulus α r = 0.5, for the cohesive internal friction angle α r =0.3, other physical and mechanical parameters α r =1.

7. A rockburst prediction method according to claim 6, characterized in that: The physical and mechanical parameters P of the rock block r Including the following: density of surrounding rock samples, elastic modulus and Poisson's ratio of surrounding rock samples, cohesion and internal friction angle of surrounding rock samples; the determination is as follows: Determine the density of surrounding rock samples by water displacement method; The elastic modulus and Poisson's ratio of the surrounding rock samples were determined by uniaxial compression test; The cohesion and internal friction angle of the surrounding rock samples were determined by triaxial compression test.

8. A rockburst prevention and control method, characterized in that: A rockburst prediction method according to any one of claims 1 to 7, further comprising step 6 after step 5, as follows: Step 6. Develop corresponding disposal measures according to the rockburst level: adopt the original design when the possibility of rockburst is low; when a minor rockburst is likely to occur, adopt measures such as sprinkling water on the cave wall and adding a protective net in the rockburst area; when a moderate rockburst is likely to occur, adopt measures such as sprinkling water on the cave wall and adding a protective net in the rockburst area, and adopt radial drilling to unload and strengthen primary support; when a strong rockburst is likely to occur, adopt advanced drilling to unload and add energy-absorbing anchor rods on the basis of the above-mentioned rockburst prevention and control measures.

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