A method and system for determining a borehole angle for a tunnel blast

Abstract

The application relates to the technical field of tunnel blasting, in particular to a method and system for determining the drilling angle of tunnel blasting, which specifically comprises the following steps: marking the vault on the surface to be constructed; performing laser scanning on the surface to be constructed to obtain local features thereof; emitting ultrasonic waves to the surface to be constructed to calculate an anisotropy index; generating a three-dimensional point cloud to obtain a voxel grid, calculating the weighted center point of each voxel grid, marking a first control point on the working face construction drawing, aligning the first and second control points to obtain a fine alignment point cloud; calculating the distance from the weighted center point in the fine alignment point cloud to the temporary plane to obtain an optimal point set, and obtaining the normal vector at the preset drilling position; calculating the joint compensation amount and the anisotropy compensation amount to obtain the final drilling angle and hole spacing. Through the method, the accuracy of the drilling angle and hole spacing is improved, the adaptability to complex construction environments is enhanced, and the blasting effect is improved.

Description

Technical Field

[0001] This invention relates to the field of tunnel blasting technology, specifically to a method and system for determining the borehole angle for tunnel blasting. Background Technology

[0002] In tunnel construction, blasting drilling is a crucial step, and the accuracy of the drilling angle directly affects the blasting effect, the quality of tunnel formation, and construction safety.

[0003] Invention patent CN116912300A discloses a tunnel blasting method based on intelligent identification of surface cracks and internal rock lithology. The specific steps include: performing three-dimensional laser scanning of the tunnel face to obtain point cloud data, and creating a solid model based on the processed point cloud data; identifying joints on the tunnel face based on the solid model, and performing numerical calculation analysis on double-hole blasting of rock at different joint angles using a numerical calculation program to obtain numerical simulation results of the fractured zone; designing the tunnel borehole parameters and borehole layout based on the numerical simulation results of the fractured zone, drilling boreholes to be blasted, and recording the borehole data; storing the borehole data in a lithology parameter database, creating a three-dimensional solid model of the rock mass for the boreholes to be blasted; calculating the charge amount for the boreholes to be blasted, and then blasting the tunnel.

[0004] Although the aforementioned existing technologies also employ three-dimensional point clouds, they do not consider the influence of local features and the vector of the surface to be constructed on the drilling angle. Moreover, in actual construction, the soil and rock conditions of the surface to be constructed are quite complex, and different soil and rock compositions and hardness have a significant impact on drilling and blasting. Summary of the Invention

[0005] This invention provides a method and system for determining the angle of tunnel blasting boreholes.

[0006] The technical solution of this invention is as follows:

[0007] A method for determining the angle of a tunnel blasting borehole specifically includes the following steps:

[0008] S1. Obtain the construction drawing of the working face and mark the arch on the surface to be constructed; perform laser scanning on the surface to be constructed from the intersection of the vertical line between the arch and the ground to obtain the local features of the surface to be constructed.

[0009] At the first threshold distance to the surface to be constructed, ultrasonic waves are emitted to the surface to be constructed to obtain the longitudinal wave velocity and transverse wave velocity of the surface to be constructed, and the anisotropy index is calculated; the surface to be constructed is scanned with a laser at the same position to generate a three-dimensional point cloud.

[0010] S2. Divide the 3D point cloud into spatial parts to obtain a voxel grid. Calculate the weighted center point of each voxel grid. Based on the weighted center point, fuse it with the local features of the surface to be constructed to obtain a fused point cloud. Mark the second control point on the fused point cloud.

[0011] S3. Mark several first control points on the working face construction drawing, align the first control points with the corresponding second control points to obtain the precise alignment point cloud;

[0012] S4. Based on three non-collinear weighted center points within a certain range at the preset borehole position of the precise alignment point cloud, determine a temporary plane, calculate the distance from all weighted center points in the precise alignment point cloud to the temporary plane, filter out qualified weighted center points with a distance less than the second threshold, form an optimal point set from all qualified weighted center points, and obtain the normal vector at the preset borehole position based on the optimal point set.

[0013] S5. Calculate the joint compensation amount and anisotropic compensation amount based on the rock mass type coefficient, the normal vector at the preset borehole location, and the anisotropy index. Summate these with the preset borehole angle to obtain the final borehole angle.

[0014] The hole spacing is determined by obtaining the adjustment amount of the hole spacing based on the anisotropy index and the preset hole spacing.

[0015] The final drilling angle is:

[0016] ,

[0017] in, For the final drilling angle, To preset the drilling angle, To compensate for the amount of friction, This is the anisotropic compensation amount.

[0018] The specific calculation method for joint compensation is as follows:

[0019] ,

[0020] in, To compensate for the amount of friction, This is the rock mass type coefficient. For joint dip angle, γ Preset safety angle;

[0021] The specific calculation method for anisotropic compensation is as follows:

[0022] ,

[0023] in, For anisotropic compensation, The anisotropy index, Let be the normal vector of the surface to be constructed. The direction vector of maximum wave velocity;

[0024] The specific calculation steps for the hole spacing adjustment are as follows:

[0025] ,

[0026] in, This is the adjustment amount for the hole spacing. For preset hole spacing, The anisotropy index, This is the rock mass integrity coefficient.

[0027] The first control point selection principle is: one at the center of the arch crown, one at each of the two arch feet, and one at each of the two arch starting points on the working face construction drawing; the second control point selection principle is: one at the center of the arch crown, one at each of the two arch feet, and one at each of the two arch starting points on the merged point cloud.

[0028] The specific steps for calculating the anisotropy index are as follows:

[0029] ,

[0030] in, , The maximum and minimum longitudinal wave velocities for ultrasonic testing. The mean longitudinal wave velocity is given.

[0031] A system for determining the angle of a tunnel blasting borehole includes:

[0032] The scanner is set at the intersection of the vertical line of the arch and the ground, and begins to scan the surface to be constructed to obtain local features of the surface to be constructed.

[0033] The detection device emits ultrasonic waves at a first threshold distance from the intersection of the vertical line of the arch and the ground to the surface to be constructed, obtains the longitudinal wave velocity and transverse wave velocity of the surface to be constructed, and calculates the anisotropy index; it then scans the surface to be constructed at the same location to generate a three-dimensional point cloud.

[0034] The second control point acquisition module divides the 3D point cloud into spatial parts to obtain a voxel grid, calculates the weighted center point of each voxel grid, and fuses it with the local features of the surface to be constructed based on the weighted center point to obtain a fused point cloud. The second control point is then marked on the fused point cloud.

[0035] The alignment module acquires the construction drawing of the working face and marks several first control points. The points corresponding to the first and second control points are aligned to obtain a coarse alignment point cloud. Based on the transformation matrix of the fused point cloud relative to the construction drawing, a fine alignment point cloud is obtained through transformation.

[0036] The module for obtaining the normal vector of the surface to be constructed determines a temporary plane based on three non-collinear weighted center points within a certain range at the preset borehole location in the precise alignment point cloud. It calculates the distance from all weighted center points in the precise alignment point cloud to the temporary plane, filters out qualified weighted center points whose distance is less than the second threshold, forms an optimal point set with all qualified weighted center points, and obtains the normal vector at the preset borehole location based on the optimal point set.

[0037] The drilling parameter calculation module calculates joint compensation and anisotropy compensation based on the rock mass type coefficient, the normal vector at the preset drilling location, and the anisotropy index. The final drilling angle is obtained by summing these values ​​with the preset drilling angle. The adjustment amount of the drilling distance is obtained based on the anisotropy index and the preset hole distance to determine the drilling distance.

[0038] The scanner includes two first support rods supported on the ground, and a chassis disposed between the first support rods, on which a first laser emitter is also disposed.

[0039] The detection device includes a triangular support rod supported on the ground, with a fixed platform at the upper end of the triangular support rod, and a second laser emitter and an ultrasonic sensor mounted on the fixed platform.

[0040] The beneficial effects of this invention are as follows:

[0041] This invention achieves intelligent determination of drilling angle and hole spacing through automated means such as laser scanning, ultrasonic detection, point cloud processing, and numerical calculation, reducing manual intervention and improving construction efficiency.

[0042] This invention acquires local features of the surface to be drilled using laser scanning, and simultaneously uses ultrasonic detection to obtain P-wave and S-wave velocities, calculating the anisotropy index. This multi-source data fusion approach provides a more comprehensive understanding of the geological features and mechanical properties of the surface to be drilled, offering more accurate foundational data for subsequent borehole angle calculations.

[0043] By fusing the weighted center points of the voxel grid with local features, a fused point cloud is obtained. This method can effectively handle noise and redundancy in point cloud data and improve the accuracy of feature extraction. Attached Figure Description

[0044] In the attached diagram:

[0045] Figure 1 Here is a diagram of the scanner structure;

[0046] Figure 2 This is a diagram of the overall structure of the detection device.

[0047] The components represented by the various reference numerals in the diagram are:

[0048] 1. Scanner; 11. First support rod; 12. Chassis; 13. First laser emitter; 2. Detection device; 21. Triangular support rod; 22. Fixing platform; 23. Second laser emitter; 24. Ultrasonic sensor. Detailed Implementation

[0049] The technical solution of this invention is as follows:

[0050] This invention provides a method and system for determining the angle of tunnel blasting boreholes.

[0051] The technical solution of this invention is as follows:

[0052] A method for determining the angle of a tunnel blasting borehole specifically includes the following steps:

[0053] S1. Obtain the construction drawing of the working face and mark the arch on the surface to be constructed; perform laser scanning on the surface to be constructed from the intersection of the vertical line between the arch and the ground to obtain the local features of the surface to be constructed.

[0054] At the first threshold distance to the surface to be constructed, ultrasonic waves are emitted to the surface to be constructed to obtain the longitudinal and transverse wave velocities and calculate the anisotropy index; at the same position, the surface to be constructed is scanned with a laser to generate a three-dimensional point cloud.

[0055] Here, "directly facing the construction surface" is a spatial concept referring to a position directly in front of the surface to be constructed, with no obstructions and a direct relative relationship. The core characteristic is the straight-line extension direction of the line of sight or path. Further, it can be understood as the first threshold distance being the vertical distance from the installation location of the detection device to the surface to be constructed. The calculation method for the first threshold distance r is as follows:

[0056] ≤r≤2R,

[0057] Where R is the width of the working face in the construction drawing.

[0058] The specific steps for calculating the anisotropy index using the longitudinal and transverse wave velocities measured by the ultrasonic sensor array are as follows:

[0059] ,

[0060] in, , The maximum and minimum longitudinal wave velocities for ultrasonic testing. The mean longitudinal wave velocity is given.

[0061] This multi-source data fusion method can provide a more comprehensive understanding of the geological features and mechanical properties of the surface to be drilled, and provide more accurate basic data for subsequent drilling angle calculations.

[0062] S2. Divide the 3D point cloud into spatial parts to obtain a voxel grid. Calculate the weighted center point of each voxel grid. Based on the weighted center point, fuse it with the local features of the surface to be constructed to obtain a fused point cloud. Mark the second control point on the fused point cloud.

[0063] The selection principle for the second control point is: the center point of the fused point cloud, one on each side of the arch foot, and one on each side of the arch starting point.

[0064] The first and second control points should be fixed geometric feature points that are clearly identifiable in the construction drawings or fused point cloud. They should also be non-collinear feature points that are easy to identify, form stable spatial constraints, and not change arbitrarily, and be less affected by external factors.

[0065] The specific steps for calculating the weighted center point of each voxel grid are as follows:

[0066] Divide the point cloud into edge lengths l For a cubic mesh, calculate the weighted center point of each voxel. :

[0067] ,

[0068] ,

[0069] in, Let j be the j-th point cloud data point within the voxel, and m be the total number of data points. for The weight, The spatial position of the voxel mesh. This is a bandwidth parameter that controls the rate of weight decay.

[0070] It is important to note here that... and These are two different concepts. The weighted center points are calculated based on the distribution of the point cloud. It is a simple position in the voxel grid space, which can be represented by the center point of the voxel grid.

[0071] This method can effectively handle noise and redundancy in point cloud data, improve the accuracy of feature extraction, and thus more accurately label the second control points.

[0072] S3. Mark several first control points on the working face construction drawing, align the first control points with the corresponding second control points to obtain a precise alignment point cloud.

[0073] The principle for selecting the first control point is: one at the center of the arch crown on the working face construction drawing, one at each of the two arch feet, and one at each of the two arch starting points.

[0074] If the first and second control points cannot be perfectly aligned, the transformation matrix of the face construction drawing and the fused point cloud is obtained. After transformation, the face construction drawing and the fused point cloud are perfectly aligned to obtain a precisely aligned point cloud.

[0075] The specific steps are as follows:

[0076] Initialize the transformation matrix and determine the minimum weighted distance between the nearest point pairs in the tunnel face construction drawing and the fused point cloud:

[0077] ,

[0078] ,

[0079] Where R is the rotation transformation matrix, t is the translation transformation matrix, and N is the total number of nearest point pairs. Let i be the i-th weighted center point within the voxel. For the construction drawings of the working face and The corresponding nearest point, For point-to-point weights, The anisotropy index is used.

[0080] Find the closest point that satisfies the constraints in the construction drawings of the tunnel face. Calculate the weighted centroids, construct the weighted covariance matrix based on the weighted centroids, and obtain the transformation matrix after decomposition.

[0081] This method can more accurately determine the normal vector of the surface to be constructed, thereby improving the accuracy of drilling angle calculation.

[0082] This invention incorporates point-to-point weights, resulting in better computational performance, reduced registration weights in highly anisotropic regions, and improved stability.

[0083] S4. Locate the point cloud within the preset borehole position setting range in the precise alignment point cloud, randomly select three non-collinear weighted center points, determine a temporary plane, calculate the distance from all weighted center points in the precise alignment point cloud to the temporary plane, filter out qualified weighted center points with a distance less than the second threshold, form an optimal point set from all qualified weighted center points, and obtain the normal vector at the preset borehole position based on the optimal point set.

[0084] The optimal set is refitted to the plane, and the eigenvector corresponding to the minimum eigenvalue is calculated by the least squares method. This eigenvector is the normal vector at the preset drilling position.

[0085] In practice, the significance of this screening method is to filter out some points that are too far away, and the resulting set of optimal points can reflect the specific planar conditions of the surface to be constructed.

[0086] In layman's terms, it involves first removing those points that are "obviously protruding or recessed" (such as protruding rocks or cracks); the remaining points are then "flattened" using mathematical methods to find a plane that best fits them. The "vertical direction" (normal vector) of this plane is the theoretical "orientation" of the surface to be drilled, which is used to guide the drilling angle.

[0087] Specifically, obtain three non-collinear weighted center points in the precise alignment cloud. Calculate the temporary plane equation:

[0088] ,

[0089] in, p Let be any point on the plane. , For plane normal vectors, after normalization .

[0090] Calculate the distance from all points to the temporary plane. :

[0091] ,

[0092] in, Set a second threshold distance ,when Then mark p Qualified weighted center point p i ;

[0093] Refit the plane with the set of optimal points to minimize the error:

[0094] ,

[0095] Satisfy constraints a, b, and c are the projection lengths of the vectors onto the x, y, and z coordinate axes.

[0096] For covariance matrix Perform feature decomposition, where N is the number of qualified weighted centroids. The mean of the qualified weighted center points is the eigenvector corresponding to the smallest eigenvalue, which is the normal vector. .

[0097] After filtering qualified weighted center points with a distance less than the second threshold, it is possible to eliminate incorrect matching point pairs that exceed the actual displacement range of the working face, and also to filter redundant points, thereby reducing the amount of calculation.

[0098] S5. Calculate the joint compensation amount and anisotropic compensation amount based on the rock mass type coefficient, the normal vector at the preset borehole location, and the anisotropy index. Summate these with the preset borehole angle to obtain the final borehole angle.

[0099] The hole spacing is determined by obtaining the adjustment amount of the hole spacing based on the anisotropy index and the preset hole spacing.

[0100] The final drilling angle is:

[0101] ,

[0102] in, For the final drilling angle, To preset the drilling angle, To compensate for the amount of friction, This is the anisotropic compensation amount.

[0103] The specific calculation method for joint compensation is as follows:

[0104] ,

[0105] in, To compensate for the amount of friction, This is the rock mass type coefficient. For joint dip angle, γ Preset safety angle;

[0106] The specific calculation method for anisotropic compensation is as follows:

[0107] ,

[0108] in, For anisotropic compensation, The anisotropy index, Let be the normal vector of the surface to be constructed. This is the direction vector of the maximum wave speed.

[0109] Based on the rock mass type coefficient, the normal vector at the preset borehole location, and the anisotropy index, the joint compensation and anisotropy compensation are calculated, and then summed with the preset borehole angle to obtain the final borehole angle. This method can fully consider the anisotropic characteristics of the rock mass, making the borehole angle more consistent with the actual geological conditions and improving the blasting effect.

[0110] The specific calculation steps for the hole spacing adjustment are as follows:

[0111] ,

[0112] in, This is the adjustment amount for the hole spacing. For preset hole spacing, The anisotropy index, This is the rock mass integrity coefficient.

[0113] Based on the anisotropy index and preset hole spacing, the adjustment amount of the hole spacing is obtained, and the borehole spacing is determined. This method can dynamically adjust the borehole spacing according to the anisotropic characteristics of the rock mass, making the blasting effect more uniform and efficient.

[0114] A system for determining the angle of a tunnel blasting borehole includes:

[0115] The scanner is set at the intersection of the vertical line of the arch and the ground, and begins to scan the surface to be constructed to obtain local features of the surface to be constructed.

[0116] The detection device emits ultrasonic waves at a first threshold distance from the intersection of the vertical line of the arch and the ground to the surface to be constructed, obtains the longitudinal wave velocity and transverse wave velocity of the surface to be constructed, and calculates the anisotropy index; it then scans the surface to be constructed at the same location to generate a three-dimensional point cloud.

[0117] The second control point acquisition module divides the 3D point cloud into spatial parts to obtain a voxel grid, calculates the weighted center point of each voxel grid, and fuses it with the local features of the surface to be constructed based on the weighted center point to obtain a fused point cloud. The second control point is then marked on the fused point cloud.

[0118] The alignment module acquires the construction drawing of the working face and marks several first control points. The points corresponding to the first and second control points are aligned to obtain a coarse alignment point cloud. Based on the transformation matrix of the fused point cloud relative to the construction drawing, a fine alignment point cloud is obtained through transformation.

[0119] The module for obtaining the normal vector of the surface to be constructed determines a temporary plane based on three non-collinear weighted center points within a certain range at the preset borehole location in the precise alignment point cloud. It calculates the distance from all weighted center points in the precise alignment point cloud to the temporary plane, filters out qualified weighted center points whose distance is less than the second threshold, forms an optimal point set with all qualified weighted center points, and obtains the normal vector at the preset borehole location based on the optimal point set.

[0120] The drilling parameter calculation module calculates joint compensation and anisotropy compensation based on the rock mass type coefficient, the normal vector at the preset drilling location, and the anisotropy index. The final drilling angle is obtained by summing these values ​​with the preset drilling angle. The adjustment amount of the drilling distance is obtained based on the anisotropy index and the preset hole distance to determine the drilling distance.

[0121] The scanner 1 includes two first support rods 11 supported on the ground, and a chassis 12 disposed between the first support rods 11. A first laser emitter 13 is also disposed on the chassis 12. Figure 1 As shown.

[0122] The detection device 2 includes a triangular support rod 21 supported on the ground. A fixed platform 22 is provided at the upper end of the triangular support rod 21. A second laser emitter 23 and an ultrasonic sensor 24 are provided on the fixed platform 22. Figure 2 As shown.

[0123] This invention achieves intelligent determination of drilling angle and hole spacing through laser scanning, ultrasonic detection, point cloud processing, and numerical calculation. This reduces manual intervention, improves construction efficiency, and the accurate calculation of drilling angle and hole spacing can reduce uncertainties in the blasting process, lower construction risks, and ensure the safety of construction personnel.

[0124] This invention combines laser scanning, ultrasonic detection, and point cloud processing to adapt to complex and varied geological conditions, providing more comprehensive geological information and a more reliable basis for calculating borehole angles and spacing. By calculating anisotropy indices and joint compensation amounts, borehole angles and spacing can be dynamically adjusted to meet construction needs under different geological conditions, improving the flexibility and adaptability of construction.

Claims

1. A method for determining the angle of a tunnel blasting borehole, characterized in that, Specifically, the following steps are included: S1. Obtain the construction drawing of the working face and mark the arch on the surface to be constructed; perform laser scanning on the surface to be constructed from the intersection of the vertical line between the arch and the ground to obtain the local features of the surface to be constructed. At the first threshold distance to the surface to be constructed, ultrasonic waves are emitted to the surface to be constructed to obtain the longitudinal wave velocity and transverse wave velocity of the surface to be constructed, and the anisotropy index is calculated; the surface to be constructed is scanned with a laser at the same position to generate a three-dimensional point cloud. The specific steps for calculating the anisotropy index are as follows: ， in, , The maximum and minimum longitudinal wave velocities for ultrasonic testing. The average longitudinal wave velocity; S2. Divide the 3D point cloud into spatial parts to obtain a voxel grid. Calculate the weighted center point of each voxel grid. Based on the weighted center point, fuse it with the local features of the surface to be constructed to obtain a fused point cloud. Mark the second control point on the fused point cloud. S3. Mark several first control points on the working face construction drawing, align the first control points with the corresponding second control points to obtain the precise alignment point cloud; S4. Based on three non-collinear weighted center points within a certain range at the preset borehole position of the precise alignment point cloud, determine a temporary plane, calculate the distance from all weighted center points in the precise alignment point cloud to the temporary plane, filter out qualified weighted center points with a distance less than the second threshold, form an optimal point set from all qualified weighted center points, and obtain the normal vector at the preset borehole position based on the optimal point set. S5. Calculate the joint compensation amount and anisotropic compensation amount based on the rock mass type coefficient, the normal vector at the preset borehole location, and the anisotropy index. Summate these with the preset borehole angle to obtain the final borehole angle. The specific calculation method for joint compensation is as follows: ， in, To compensate for the amount of friction, This is the rock mass type coefficient. For joint dip angle, γ Preset safety angle; The specific calculation method for anisotropic compensation is as follows: ， in, For anisotropic compensation, The anisotropy index, Let be the normal vector of the surface to be constructed. The direction vector of maximum wave velocity; The hole spacing is determined by obtaining the adjustment amount of the hole spacing based on the anisotropy index and the preset hole spacing; The specific calculation steps for the hole spacing adjustment are as follows: ， in, This is the adjustment amount for the hole spacing. For preset hole spacing, The anisotropy index, This is the rock mass integrity coefficient.

2. The method for determining the angle of tunnel blasting boreholes according to claim 1, characterized in that, The final drilling angle is: ， in, For the final drilling angle, To preset the drilling angle, To compensate for the amount of friction, This is the anisotropic compensation amount.

3. The method for determining the angle of tunnel blasting boreholes according to claim 1, characterized in that, The first control point selection principle is: one at the center of the arch crown, one at each of the two arch feet, and one at each of the two arch starting points on the working face construction drawing; the second control point selection principle is: one at the center of the arch crown, one at each of the two arch feet, and one at each of the two arch starting points on the merged point cloud.

4. A system for determining the angle of a tunnel blasting borehole, used to implement the method for determining the angle of a tunnel blasting borehole as described in any one of claims 1-3, characterized in that, include: The scanner (1) is set at the intersection of the vertical line of the arch and the ground to start scanning the surface to be constructed and obtain the local features of the surface to be constructed. The detection device (2) emits ultrasonic waves at the first threshold distance from the intersection of the vertical line where the arch is located and the ground to obtain the longitudinal wave velocity and transverse wave velocity of the surface to be constructed, and calculates the anisotropy index; it scans the surface to be constructed at the same position to generate a three-dimensional point cloud. The second control point acquisition module divides the 3D point cloud into spatial parts to obtain a voxel grid, calculates the weighted center point of each voxel grid, and fuses it with the local features of the surface to be constructed based on the weighted center point to obtain a fused point cloud. The second control point is then marked on the fused point cloud. The alignment module acquires the construction drawing of the working face and marks several first control points. The points corresponding to the first and second control points are aligned to obtain a coarse alignment point cloud. Based on the transformation matrix of the fused point cloud relative to the construction drawing, a fine alignment point cloud is obtained through transformation. The module for obtaining the normal vector of the surface to be constructed determines a temporary plane based on three non-collinear weighted center points within a certain range at the preset borehole location in the precise alignment point cloud. It calculates the distance from all weighted center points in the precise alignment point cloud to the temporary plane, filters out qualified weighted center points whose distance is less than the second threshold, forms an optimal point set with all qualified weighted center points, and obtains the normal vector at the preset borehole location based on the optimal point set. The drilling parameter calculation module calculates joint compensation and anisotropy compensation based on the rock mass type coefficient, the normal vector at the preset drilling location, and the anisotropy index. The final drilling angle is obtained by summing these values ​​with the preset drilling angle. The adjustment amount of the drilling distance is obtained based on the anisotropy index and the preset hole distance to determine the drilling distance.

5. The system for determining the angle of tunnel blasting boreholes according to claim 4, characterized in that, The scanner (1) includes two first support rods (11) supported on the ground, and a chassis (12) disposed between the first support rods (11), on which a first laser emitter (13) is also disposed.

6. The system for determining the angle of tunnel blasting boreholes according to claim 4, characterized in that, The detection device (2) includes a triangular support rod (21) supported on the ground. A fixed platform (22) is provided at the upper end of the triangular support rod (21). A second laser emitter (23) and an ultrasonic sensor (24) are provided on the fixed platform (22).

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