A method for eliminating the risk of rock burst in tunnel excavation

Abstract

The present invention discloses a method for eliminating rockburst risks in tunnel excavation, which relates to the technical field of rockburst prevention and control. By adopting three-dimensional visualization technology, the geological structure between the heading face and its related points is clearly displayed. By deeply analyzing the rock mass characteristic parameters to establish the correlation between the structure coefficient and the stability base value, scientific instability value calculations can be provided for each related point, which helps to comprehensively evaluate the impact of the rock mass on the heading face. By real-time monitoring and analyzing the instability risk value, technicians can, according to the actual situation of the heading face and based on the instability risk value of the heading face, flexibly adjust the rockburst prevention measures to ensure that the stress is moderately released, avoid the generation of high-stress areas, and reduce the possibility of rockburst occurrence. Real-time monitoring and dynamic adjustment are realized, the rockburst prevention measures are optimized, and the operation safety and efficiency are significantly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of rockburst prevention and control, and particularly to a method for eliminating rockburst risks in tunnel excavation. Background Art

[0002] The rockburst risk in tunnel excavation is a phenomenon in which underground rock masses suddenly release energy under stress, usually accompanied by dangerous situations such as violent fractures and rock splashes; rockbursts seriously threaten the safety of personnel and machinery in deep underground projects. Therefore, for tunnel excavation, the elimination of rockburst risks is particularly important;

[0003] Currently, the elimination of rockburst risks usually adopts presplitting blasting or pressure relief holes to release local high stresses. The specific blasting range and pressure relief holes are processed by on-site technicians based on their own experience. This method has great uncertainty and often makes it difficult to accurately control the range and intensity of stress release. Excessive blasting may cause further damage to local rock masses and increase the risk of subsequent excavation; when the pressure relief by drilling is insufficient, high stress areas still exist and the rockburst risk cannot be completely eliminated. Summary of the Invention

[0004] Based on this, in view of the problems mentioned in the above background art, it is necessary to provide a method for eliminating rockburst risks in tunnel excavation.

[0005] The object of the present invention can be achieved through the following technical solutions: A method for eliminating rockburst risks in tunnel excavation, comprising the following steps:

[0006] R1: Analyze the spatial distribution, intensity, and frequency of microseismic events through microseismic monitoring data to determine potential points where rockbursts may occur and their corresponding potential risk values; calculate the interval distances between each rockburst point and the tunnel face, select the maximum interval distance among them and denote it as Zmax, and select the minimum interval distance among them and denote it as Zmin;

[0007] R2: With the tunnel face as the center, draw a circle with a certain distance as the radius to form the relevant range of the tunnel face, and regard the potential points within the relevant range as the relevant points of the tunnel face; obtain the geological structure information inside the rock mass within the relevant range based on geological radar scanning, three-dimensional laser scanning, and geological exploration, generate a three-dimensional visualization image of the rock mass structure between the tunnel face and the relevant points, and denote it as a three-dimensional model diagram. Thus, several three-dimensional model diagrams can be obtained;

[0008] R3: Conduct geological exploration before tunnel excavation to obtain the rock mass characteristic parameters between the tunnel face and the relevant points. The rock mass characteristic parameters include rock mass types, the number of rock mass structures, the structural type of each rock mass structure, and the positional relationship between the rock mass structure and the tunnel face; analyze based on the rock mass characteristic parameters to measure their influence on the tunnel face, and accordingly obtain the instability risk value of the tunnel face;

[0009] R4: The rockburst risk elimination based on the instability risk value of the tunnel face is specifically as follows:

[0010] Step 1: Retrieve the instability risk value and compare and analyze it with the set risk interval. When the instability risk value is greater than the maximum value in the set risk interval, then execute Step 2; when the instability risk value is within the set interval, then execute Step 3; when the instability risk value is less than the minimum value in the set risk interval, then execute Step 4:

[0011] Step 2: Perform blasting pressure relief according to the blasting parameters. The specific blasting parameters include the blasting radius R 爆破 and the blasting charge Q 爆破 ; after the blasting pressure relief is completed, return to R1;

[0012] Step 3: Perform drilling pressure relief according to the drilling parameters. The drilling parameters include the number of drill holes S and the drilling depth H; after the drilling pressure relief is completed, return to R1;

[0013] Step 4: Excavate according to the footage parameters. The specific footage parameters include the footage speed V safe and the farthest safe distance L safe ;

[0014] R5: Repeat the above steps R1 - R4 until the tunnel excavation work is completed.

[0015] In some embodiments, the calculation process of the blasting parameters is as follows:

[0016]

[0017] where η is the set range conversion coefficient, K represents the blasting coefficient, and UT is the instability risk value of the tunnel face.

[0018] In some embodiments, the calculation process of the drilling parameters is as follows:

[0019]

[0020] where α1 and α2 are the set empirical coefficients, W is the area of the tunnel face, R 孔 is the radius of the pressure relief hole; Zmax is the maximum distance between the tunnel face and the potential rockburst point.

[0021] In some embodiments, the calculation process of the footage parameters is as follows:

[0022]

[0023] Where λ1 and λ2 are respectively the set adjustment coefficients, Vmax is the set maximum tunneling speed. The greater the instability risk value of the tunnel face, the lower the footage speed; Zmin is the minimum distance between the tunnel face and the potential rockburst point.

[0024] In some embodiments, analysis is performed based on rock mass characteristic parameters to measure their influence on the tunnel face. The specific analysis steps are as follows:

[0025] 5-1: Set that different structural types respectively correspond to a structural coefficient, retrieve the structural type, and compare it with all the set structural types to match the corresponding structural coefficient;

[0026] 5-2: Calculate the structural plane area corresponding to each structure according to the 3D model diagram and denote it as βj, where j = 1, 2, 3... J, J takes positive integer values, J is the total number of structural planes in the 3D model, and j is the serial number of any one of the structural planes;

[0027] 5-3: According to the 3D model diagram, make the normal vectors of the tunnel face and the structural plane and denote them as and Use the dot product formula to calculate the cosine of the angle between the normal vector of the tunnel face and the normal vector of the rock mass structural plane. The specific dot product calculation formula is:

[0028]

[0029] 5-4: According to the 3D model diagram, denote any point on the tunnel face and its coordinates as Oi(Xi, Yi, Zi). Set the plane equation coefficients of the structural plane as: A, B, C, and D, and calculate the distance between the structural plane and any point on the tunnel face through geometric formulas. Select the shortest distance among them as the calibration distance and denote it as Lminj; The specific geometric calculation formula is:

[0030]

[0031] 5-5: Set that different rock mass types respectively correspond to a rock mass stability base value, retrieve the rock mass type, and compare it with all the set types to match the corresponding rock mass stability base value and denote it as T;

[0032] 5-6: Obtain the structural coefficient βj, structural plane area Gj, cosine of the angle between the structural plane and the tunnel face cosθj, and calibration distance Lminj of each structure, and perform normalization processing on them and the rock mass base value T corresponding to the tunnel face and take their numerical values. Perform formula-based calculation and analysis on the numerical values to obtain the instability value GL of the relevant point to the tunnel face; The specific calculation formula is

[0033]

[0034] where γ1, γ2, γ3, and γ4 are respectively the set weight constants; thus, the instability values of each relevant point with respect to the tunnel face are denoted as GLa, where a = 1, 2, 3,..., A, A takes positive integer values, A is the total number of relevant points within the relevant range, and a is any one of the relevant points;

[0035] 5 - 7: Retrieve the potential risk values of each relevant point, denoted as Ua; normalize the instability values GLa of each relevant point with respect to the tunnel face, the potential risk values Ua of the relevant points, and the rock mass stability base value T, and take their numerical values. Through numerical analysis, the instability risk value UT of the tunnel face is obtained. The specific calculation formula is:

[0036]

[0037] where μ1, μ2, and μ3 are respectively the set weight constants.

[0038] In some embodiments, the derivation process of the plane equation of the structural plane is as follows:

[0039] Step 1: Construct vectors, specifically:

[0040] Select three points on the structural plane as P1(x1, y1, z1), P2(x2, y2, z2), and P3(x3, y3, z3) respectively; in three - dimensional space, any two points can determine a vector. Select one of the points, P1, and construct two vectors pointing from P1 to P2 and P3 respectively, denoted as and Specifically and The coordinate representations of are:

[0041]

[0042] Step 2: Calculate the normal vector, specifically:

[0043] Through the cross - product (outer product) of vectors and the normal vector of the plane can be obtained as The normal vector is a vector perpendicular to the structural plane, and its components A, B, and C can be calculated by the following formulas:

[0044]

[0045] Specifically expanded as:

[0046] A = (y2 - y1)(z3 - z1)-(y3 - y1)(z2 - z1)

[0047] B = (z2 - z1)(x3 - x1)-(z3 - z1)(x2 - x1)

[0048] C = (x2 - x1)(y3 - y1) - (x3 - x1)(y2 - y1)

[0049] Normal vector is the normal vector of the structural plane;

[0050] Step 3: Determine the plane equation, specifically:

[0051] Based on the normal vector The plane equation can be written as:

[0052] A(x - x1) + B(y - y1) + C(z - z1) = 0

[0053] Expand and simplify it to obtain the standard form of the plane equation:

[0054] Ax + By + Cz + D = 0

[0055] Among them, the constant term D can be obtained by substituting P1(x1, y1, z1):

[0056] D = -(Ax1 + By1 + Cz1)

[0057] Thus, the coefficients of the plane equation of the structural plane can be deduced as: A, B, C, D.

[0058] Compared with the prior art, the beneficial effects of the present invention are:

[0059] 1. By adopting the three-dimensional visualization technology, the geological structure between the heading face and its related points is clearly displayed, enabling technicians to have a more intuitive understanding of potential risk points, accurately identifying geological features closely related to the heading face, and thus formulating targeted risk response strategies;

[0060] 2. By deeply analyzing the rock mass characteristic parameters to establish the correlation between the structural coefficient and the stability base value, scientific instability value calculations can be provided for each related point, helping to comprehensively evaluate the impact of the rock mass on the heading face, and thus providing data support for the effective implementation of the rockburst risk elimination strategy for tunnel excavation;

[0061] 3. By real-time monitoring and analyzing the instability risk value, technicians can flexibly adjust the rockburst prevention measures according to the actual situation of the heading face and based on the instability risk value of the heading face, ensure that the stress is moderately released, avoid the generation of high stress areas, and reduce the possibility of rockburst occurrence; realizing real-time monitoring and dynamic adjustment, optimizing the rockburst prevention measures, and significantly improving the operation safety and efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0063] Figure 1 It is a principle block diagram of the present invention. Detailed implementation manners

[0064] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following will give a detailed description of the specific implementation manners of the present invention with reference to the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein. Those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0065] As Figure 1 shown, a method for eliminating the risk of rock burst for tunnel excavation includes the following steps:

[0066] R1: Analyze the spatial distribution, intensity, frequency, etc. of microseismic events through microseismic monitoring data to determine the potential points where rock burst may occur, their corresponding potential risk values (it should be noted that the potential risk value refers to the possible value of rock burst at the potential point), and specific locations; calculate the interval distance between each rock burst point and the tunnel face, select the maximum interval distance among them and denote it as Zmax, and select the minimum interval distance among them and denote it as Zmin;

[0067] R2: With the tunnel face as the center and a certain distance (the certain distance here is usually set by the personnel in this field according to the actual needs of on-site excavation) as the radius, a circle is drawn to form the relevant range of the tunnel face, and the potential points within the relevant range are taken as the relevant points of the tunnel face; the geological structure information inside the rock mass within the relevant range is obtained by geological radar scanning, three-dimensional scanning and geological exploration, wherein the geological structure information includes the three-dimensional position and direction of the tunnel face and the rock layers, joints, cracks and faults between the tunnel face and the relevant points; the rendering function of the modeling software is used to generate a three-dimensional visualization image of the rock structure between the tunnel face and the relevant points, and it is recorded as a three-dimensional model map, thereby obtaining several three-dimensional model maps, wherein one relevant point corresponds to a three-dimensional model map, showing the details of the rock structure of the point and its surroundings, and multiple relevant points will generate multiple models; the rendering function of the modeling software is used to generate a three-dimensional visualization image of the rock structure between the tunnel face and the relevant points (the rock structure here refers to joints, cracks and faults, etc.); each structural surface can be marked with transparent, semi-transparent or different colors to help clearly show their spatial relationship with the tunnel face;

[0068] By adopting 3D visualization technology, the geological structure between the tunnel face and its related points is clearly displayed, allowing technicians to have a more intuitive understanding of potential risk points and accurately identify geological features closely related to the tunnel face, thereby formulating targeted risk response strategies.

[0069] R3: The rock mass characteristic parameters between the tunnel face and relevant points are obtained by conducting site exploration before tunnel excavation. The rock mass characteristic parameters include rock mass type, number of rock mass structures, structural type of each rock mass structure, and positional relationship between rock mass structure and tunnel face. Specific rock mass structures include joints, fissures and faults. When the positional relationship between the rock mass structure and the tunnel face is a tangent relationship, the greater the impact on the stability of the tunnel face. Joints, fissures and faults are natural weak surfaces in the rock mass, which greatly weaken the integrity of the rock mass. When the rock mass structure surface is tangent to the tunnel face, the support force on the tunnel face is uneven, especially the tangent position is more likely to produce uneven stress concentration, which in turn affects the stability of the tunnel face and increases the risk of rock mass sliding, collapse, and even rock burst. According to the rock mass characteristic parameters, analysis is carried out to measure its impact on the tunnel face, and the instability risk value of the tunnel face is obtained accordingly. Specifically:

[0070] Set different structural types to correspond to a structural coefficient respectively, retrieve the structural type, and compare it with all the set structural types to match the corresponding structural coefficient, denoted as βj. It should be noted that for the structural coefficients corresponding to different structural types, a fault is a large fracture zone with obvious displacement in the rock mass. Since fault zones generally have greater penetrability and high stress concentration effects, they have a greater impact on the farthest safe distance. Specifically, the structural coefficient corresponding to a fault is greater than that corresponding to a fissure; the structural coefficient corresponding to a fissure is greater than that corresponding to a joint;

[0071] Calculate the area of the structural plane corresponding to each structure according to the three-dimensional model diagram, denoted as Gj, where j = 1, 2, 3... J, J takes positive integers, J is the total number of structural planes in the three-dimensional model, and j is the serial number of any one of the structural planes. It should be noted that the larger the area of the structural plane, the greater its impact on the stability of the tunnel face, because it not only expands the range of stress concentration but also increases the potential scale of rock mass failure and the risk of rockburst;

[0072] According to the three-dimensional model diagram, make the normal vectors of the tunnel face and the structural plane, and denote them as and Calculate the cosine of the angle between the normal vector of the tunnel face and the normal vector of the rock mass structural plane, which can be calculated by the dot product formula. The specific dot product calculation formula is:

[0073]

[0074] According to the three-dimensional model diagram, denote any point on the tunnel face and its coordinates as Oi(Xi, Yi, Zi), and denote the plane equation coefficients of the structural plane corresponding to the structure as A, B, C, D; calculate the distance Lij between the structural plane and any point on the tunnel face through geometric formulas, and select the shortest distance among them as the calibration distance, denoted as Lminj; the specific geometric calculation formula is:

[0075]

[0076] Among them, the plane equation coefficients A, B, C, D of the structural plane are obtained through geometric relationship derivation; the specific derivation process is:

[0077] Step 1: Construct vectors, specifically:

[0078] Select three points on the structural plane as P1(x1, y1, z1), P2(x2, y2, z2) and P3(x3, y3, z3) respectively; in three-dimensional space, any two points can determine a vector. Select one of the points P1 and construct two vectors pointing from P1 to P2 and P3 respectively, denoted as and Specifically and The coordinate representation is:

[0079]

[0080] Step 1: Calculate the normal vector, specifically:

[0081] Through the vector and The cross product (outer product) of can obtain the normal vector of the plane The normal vector is a vector perpendicular to the structural plane, and its components A, B, and C can be calculated by the following formula:

[0082]

[0083] Specifically expanded as:

[0084] A = (y2 - y1)(z3 - z1) - (y3 - y1)(z2 - z1)

[0085] B = (z2 - z1)(x3 - x1) - (z3 - z1)(x2 - x1)

[0086] C = (x2 - x1)(y3 - y1) - (x3 - x1)(y2 - y1)

[0087] The normal vector is the normal vector of the structural plane;

[0088] Step 3: Determine the plane equation, specifically:

[0089] Based on the normal vector The plane equation can be written as:

[0090] A(x - x1) + B(y - y1) + C(z - z1) = 0

[0091] Expand and simplify it to get the standard form of the plane equation:

[0092] Ax + By + Cz + D = 0

[0093] Among them, the constant term D can be obtained by substituting P1(x1, y1, z1):

[0094] D = -(Ax1 + By1 + Cz1)

[0095] From this, the coefficients of the plane equation of the structural plane can be deduced as: A, B, C, D;

[0096] Set a corresponding rock mass stability base value for each different rock mass type, retrieve the rock mass type, and compare it with all the set types to match the corresponding rock mass stability base value, denoted as T; it should be noted that different rock mass types correspond to different rock mass stability base values. For example, brittle rocks (such as granite and quartzite) are prone to sudden fractures and are accompanied by relatively large energy releases, and the rock mass stability base values corresponding to such rocks are smaller;

[0097] In summary, the structure coefficient βj, the structural plane area Gj, the cosine of the angle between the structural plane and the tunnel face cosθj, and the calibration distance Lminj of each structure can be obtained, and they are normalized with the rock mass base value T corresponding to the tunnel face and their numerical values are taken. The numerical values are calculated and analyzed formulaically to obtain the instability value GL of the relevant points with respect to the tunnel face; the specific calculation formula is

[0098]

[0099] where γ1, γ2, γ3, and γ4 are respectively the set weight constants. It can be seen from the formula that when the structure coefficient is larger and the structural plane area is larger, it indicates that the structure has a greater impact on the stability of the tunnel face, and the instability value is larger; when the calibration distance is smaller, it indicates that the structure is closer to the tunnel face, and the instability value is larger; when the positional relationship between the structural plane and the tunnel face is tangent, then θ is 90°. Compared with other positional relationships, the position at this time has the greatest impact on the tunnel face, and the instability value is larger; thus, the instability values of each relevant point with respect to the tunnel face are denoted as GLa, where a = 1, 2, 3... A, A takes positive integer values, A is the total number of relevant points within the relevant range, and a is any one of the relevant points;

[0100] Retrieve the potential risk value of each relevant point, denoted as Ua; normalize the instability value GLa of each relevant point with respect to the tunnel face, the potential risk value Ua of the relevant point, and the rock mass stability base value T and take their numerical values. Through numerical analysis, the instability risk value UT of the tunnel face is obtained. The specific calculation formula is:

[0101]

[0102] where μ1, μ2, and μ3 are respectively the set weight constants. It can be seen from the formula that when the potential risk value of each relevant point is larger and the instability value is larger, it indicates that the potential rockburst points and the rock mass structure between the potential rockburst points and the tunnel face have a greater impact on the stability of the tunnel face, and the instability risk value is larger; when the rock mass stability base value is smaller, the instability risk value is larger;

[0103] By deeply analyzing the rock mass characteristic parameters to establish the correlation between the structure coefficient and the stability base value, it is possible to provide scientific instability value calculations for each relevant point, which helps to comprehensively evaluate the impact of the rock mass on the tunnel face, thereby providing data support for the effective implementation of the rockburst risk elimination strategy for tunnel excavation.

[0104] R4: Eliminate the rockburst risk based on the instability risk value of the tunnel face to ensure the safety of tunnel excavation. The specific risk elimination steps are as follows:

[0105] Step 1: Retrieve the instability risk value and compare it with the set risk range. When the instability risk value is greater than the maximum value in the set risk range, it indicates that the tunnel face is threatened by a relatively large rockburst risk and the risk is significant, then execute Step 2. When the instability risk value is within the set range, then execute Step 3. When the instability risk value is less than the minimum value in the set risk range, it indicates that the potential rockburst risk of the tunnel face is relatively small, and at this time, only the farthest safe distance needs to be controlled, then execute Step 4:

[0106] Step 2: Perform blasting pressure relief according to the blasting parameters: Ensure that the rock mass stress is properly released through directional blasting, prevent the tunnel face from entering the high-stress area, and avoid uncontrolled rockburst. The specific blasting parameters include the blasting radius R 爆破 and the blasting charge Q 爆破 ; The specific calculation formula is:

[0107]

[0108] where η is the set range conversion coefficient, and K represents the blasting coefficient, which is generally obtained through experiments or engineering experience. When the blasting is completed, then return to R1;

[0109] Step 3: Perform borehole pressure relief according to the borehole parameters: Release the local high stress through boreholes to reduce the possibility of rockburst. The specific borehole parameters include the number of boreholes S and the borehole depth H; The specific calculation formula is:

[0110]

[0111] where α1 and α2 are the set empirical coefficients, W is the area of the tunnel face, R 孔 is the radius of the pressure relief hole; Zmax is the maximum distance between the tunnel face and the potential rockburst point. After the pressure relief is completed, then return to R1;

[0112] Step 4: Excavate according to the footage parameters. The specific footage parameters include the footage speed V safe and the farthest safe distance L safe , The specific calculation formula is:

[0113]

[0114] Where λ1 and λ2 are respectively the set adjustment coefficients, Vmax is the set maximum tunneling speed (the optimal tunneling speed when there is no rockburst risk). When the instability risk value of the tunnel face is greater, the footage speed is lower; Zmin is the minimum distance between the tunnel face and the potential rockburst point; the distance between the potential rockburst point and the tunnel face is adjusted through the footage parameter to ensure that the distance between the excavation position and the potential rockburst point is not less than the farthest safe distance, so as to control the rockburst risk during the advancement of the tunnel face.

[0115] R5: Repeat the above steps R1 - R4 until the tunnel excavation work is completed;

[0116] By real-time monitoring and analyzing the instability risk value, technicians can flexibly adjust the rockburst prevention measures according to the actual situation of the tunnel face and based on the instability risk value of the tunnel face, ensure that the stress is moderately released, avoid the generation of high-stress areas, and reduce the possibility of rockburst occurrence; real-time monitoring and dynamic adjustment are realized, the rockburst prevention measures are optimized, and the operation safety and efficiency are significantly improved.

[0117] The above formulas are all obtained by collecting a large amount of data for software simulation and selecting a formula close to the true value. The coefficients in the formula are set by technicians in this field according to the actual situation.

[0118] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0119] The above-described embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent should be subject to the appended claims.

Claims

1. A method for eliminating rock burst risk in tunnel excavation, characterized in that: The following steps are involved: R1: Analyze the spatial distribution, intensity and frequency of microseismic events through microseismic monitoring data to determine the potential points where rock bursts may occur and their corresponding potential risk values; Calculate the distance between each rockburst point and the tunnel face, select the largest distance as Zmax, and select the smallest distance as Zmin; R2: With the tunnel face as the center and the preset distance as the radius, a circle is drawn to form the relevant range of the tunnel face, and the potential points within the relevant range are taken as the relevant points of the tunnel face; the geological structure information inside the rock mass within the relevant range is obtained based on geological radar scanning, three-dimensional laser scanning and geological exploration, and a three-dimensional visualization image of the rock mass structure between the tunnel face and the relevant points is generated, and it is recorded as a three-dimensional model map, thereby obtaining several three-dimensional model maps; R3: Before tunnel excavation, the rock mass characteristic parameters between the tunnel face and relevant points are obtained by conducting site exploration, where the rock mass characteristic parameters include rock mass type, number of rock mass structures, structural type of each rock mass structure, and positional relationship between rock mass structure and tunnel face; the rock mass characteristic parameters are analyzed to measure their influence on the tunnel face, and the instability risk value of the tunnel face is obtained accordingly; R4: Elimination of rockburst risk based on the instability risk value of the tunnel face is as follows: Step 1: retrieve the instability risk value and compare it with the set risk range. When the instability risk value is greater than the maximum value in the set risk range, execute step 2: when the instability risk value is within the set range, execute step 3; when the instability risk value is less than the minimum value in the set risk range, execute step 4: Step 2: Perform blasting decompression according to blasting parameters. Specific blasting parameters include blasting radius R 爆破 and blasting charge Q 爆破 ; When the blasting pressure relief is completed, it returns to R1; Step 3: Perform drilling pressure relief according to drilling parameters, the drilling parameters include the number of holes S and the drilling depth H; when the drilling pressure relief is completed, return to R1; Step 4: Excavate according to the footage parameters. The specific footage parameters include the footage speed V safe and the maximum safety distance L safe ; R5: Repeat the above steps R1-R4 until the tunnel excavation work is completed; The rock mass characteristic parameters are analyzed to measure their influence on the tunnel face. The specific analysis steps are as follows: 5-1: Set different structure types to correspond to a structure coefficient, call the structure type, and compare it with all the set structure types to match the corresponding structure coefficient; 5-2: According to the three-dimensional model diagram, the structural surface area corresponding to each structure is calculated and recorded as βj, where j = 1, 2, 3...J, J is a positive integer, J is the total number of structural surfaces in the three-dimensional model, and j is the serial number of any structural surface; 5-3: Based on the 3D model, the normal vectors of the tunnel face and the structural surface are drawn and recorded as and The dot product formula is used to calculate the cosine of the angle between the normal vector of the tunnel face and the normal vector of the rock mass structural surface. The specific dot product calculation formula is: 5-4: According to the three-dimensional model diagram, mark any point on the tunnel surface and its coordinates as Oi (Xi, Yi, Zi), set the plane equation coefficients of the structural surface as: A, B, C and D, and use the geometric formula to calculate the distance between the structural surface and any point on the tunnel surface by combining the coordinates of any point on the tunnel surface, and select the shortest distance as the calibration distance and record it as Lminj; the specific geometric calculation formula is: 5-5: Set different rock mass types to correspond to a rock mass stability base value, retrieve the rock mass type, and compare it with all the set types to match the corresponding rock mass stability base value, which is recorded as T; 5-6: The structural coefficient βj, structural surface area Gj, cosine of the angle between the structural surface and the tunnel face cosθj, and calibrated distance Lminj of each structure are obtained, and the rock mass base value T corresponding to the tunnel face is normalized and its value is taken. The numerical value is calculated and analyzed by formula to obtain the instability value GL of the tunnel face at the relevant point; the specific calculation formula is: Among them, γ1, γ2, γ3, and γ4 are respectively the set weight constants; thus, the instability value of each relevant point to the tunnel face is recorded as GLa, where a=1,2,3……A, A is a positive integer, A is the total number of relevant points within the relevant range, and a is any relevant point among them; 5-7: The potential risk value of each relevant point is retrieved and recorded as Ua; the instability value GLa of each relevant point on the tunnel face, the potential risk value Ua of the relevant point and the rock mass stability base value T are normalized and their values ​​are taken, and the instability risk value UT of the tunnel face is obtained by numerical analysis. The specific calculation formula is: Among them, μ1, μ2, and μ3 are the set weight constants respectively.

2. A method for eliminating rock burst risk in tunnel excavation according to claim 1, characterized in that: The calculation process of blasting parameters is: Where η is the set range conversion coefficient, K represents the blasting coefficient, and UT is the instability risk value of the tunnel face.

3. A method for eliminating rock burst risk in tunnel excavation according to claim 2, characterized in that: The calculation process of drilling parameters is: Among them, α1 and α2 are set empirical coefficients, W is the area of ​​the tunnel face, R 孔 is the radius of the pressure relief hole; Zmax is the maximum spacing distance between the tunnel face and the potential rock burst point.

4. A method for eliminating rock burst risk in tunnel excavation according to claim 3, characterized in that: The calculation process of footage parameters is: Where λ1 and λ2 are the set adjustment coefficients, Vmax is the set maximum excavation speed, and Zmin is the minimum spacing distance between the tunnel face and the potential rock burst point.

5. A method for eliminating rock burst risk in tunnel excavation according to claim 4, characterized in that: The derivation process of the plane equation of the structural surface is: Step 1: Construct a vector, specifically: Select three points on the structural surface, namely P1 (x1, y1, z1), P2 (x2, y2, z2) and P3 (x3, y3, z3); ​​in three-dimensional space, any two points determine a vector, select one point P1, and construct two vectors pointing from P1 to P2 and P3, respectively, denoted as and Specific and The coordinates are expressed as: Step 1: Calculate the normal vector, specifically: By vector and The cross product of Normal vector It is a vector perpendicular to the structural surface, and its components A, B, and C are calculated by the following formula: Specifically expanded as follows: A=(y2-y1)(z3-z1)-(y3-y1)(z2-z1) B=(z2-z1)(x3-x1)-(z3-z1)(x2-x1) C=(x2-x1)(y3-y1)-(x3-x1)(y2-y1) Normal vector is the normal vector of the structural surface; Step 3: Determine the plane equation, specifically: Based on normal vector The plane equation is written as: A(x-x1)+B(y-y1)+C(z-z1)=0 Expanding and simplifying it gives the standard plane equation form: Ax+By+Cz+D=0 The constant term D can be obtained by substituting P1(x1,y1,z1) into: D=-(Ax1+By1+Cz1) The plane equation coefficients of the structural surface are derived as follows: A, B, C, D.

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