A method and system for rapid calculation of semi-wall hole rate of slope presplitting blasting

Abstract

The present application belongs to the technical field of traffic management, and particularly relates to a method and system for quickly calculating the semi-wall hole rate of slope pre-splitting blasting, which comprises the following steps: S1, obtaining the design parameters of the blasting excavation surface, the design parameters including positioning coordinates, azimuth, and inclination; obtaining the point cloud data of the rock wall surface after blasting excavation; S2, calculating the center point coordinates, normal direction, and generating a characteristic plane of the designed excavation surface according to the design parameters and the point cloud data, and fitting the plane to the actual excavation surface; S3, in the fitted excavation surface, the blast hole is equally divided along the axial direction according to a specific number, the effective point set with the radial deviation in a specific interval is screened out, and the ratio of the length sum of the blast hole traces on the actual excavation surface to the total drilling footage of the excavation surface is calculated to obtain the semi-wall hole rate result. The semi-wall hole rate of the blasting excavation surface calculated directly from the design parameters and the observation point coordinates is not disturbed by human factors, is fast, and is high in accuracy.

Description

Technical Field

[0001] This invention belongs to the field of traffic management technology, specifically relating to a rapid calculation method and system for the half-wall porosity of slope pre-splitting blasting. Background Technology

[0002] In the construction of certain large-scale projects, such as high slope excavation, underground cavern excavation, and underground tunnel excavation, due to the massive scale of the project, drilling and blasting technology must be used to accelerate the construction progress. Blasting excavation will result in an uneven excavation surface.

[0003] During construction, strict requirements are placed on the flatness of the blasting excavation. Among these requirements, the half-wall porosity is a core quality indicator for evaluating the effectiveness of pre-splitting blasting or smooth blasting. The half-wall porosity refers to the ratio of the total length of the borehole traces remaining on the slope surface in the test section to the total number of boreholes drilled in the test section. A high half-wall porosity indicates less rock mass damage, intact pre-splitting cracks, reduced rainwater infiltration and rock weathering, and extended slope service life.

[0004] At present, smooth blasting and pre-splitting blasting are mostly used for excavation. The flatness of the excavation surface is mostly measured by manual tape measure, which is inefficient and inaccurate.

[0005] Existing technical solutions: Flatness and half-wall porosity are measured manually using a measuring tape. The measuring personnel directly measure the flatness and half-wall porosity by having the measuring tape contact the test surface.

[0006] Disadvantages of existing technologies: 1. Huge workload: Manual measurement with a measuring tape is slow in practice, and the excavation surface is generally very large, making it impossible to measure everything manually. 2. Large error: Because it is manual measurement, there are errors in human operation and statistical data, leading to large errors in the measurement results. 3. Dangerous working environment: When manually measuring steep slopes or slopes wading through water, the steep slopes pose a risk of falls, seriously threatening the lives of surveyors.

[0007] Regarding the calculation of half-wall porosity, the existing technology discloses a patent titled "An Intelligent Identification System and Method for Half-Wall Porosity in Pre-Splitting Blasting" (Publication No. CN119599517A). This system and method includes a front-end display platform for data interaction via computer and a back-end computing system. The calculation results are displayed and viewed through the front-end display platform, which consists of a menu bar, toolbar, display window, and command line. The back-end computing system mainly includes modules such as a half-wall porosity image database, image denoising, image segmentation, data statistical analysis, and recognition calculation. Using UAV oblique photography technology with or without RTK functionality, half-wall porosity photos are collected on the steps on both sides of the platform. A three-dimensional image database with labeled half-wall porosity information is established, and a computer deep learning-based intelligent identification algorithm for half-wall porosity is developed to achieve accurate identification of half-wall porosity. Summary of the Invention

[0008] The purpose of this invention is to provide a method for monitoring the half-wall porosity of a blasting excavation face based on total station point measurement, which can solve the problems of large workload, low efficiency and low accuracy in the previous measurement of the half-wall porosity of the excavation face.

[0009] To achieve the above objectives, the following technical solutions are proposed:

[0010] A rapid calculation method for half-wall porosity in slope pre-splitting blasting includes the following steps:

[0011] S1, Obtain the design parameters of the blasting excavation face, including positioning coordinates, orientation, and inclination angle; Obtain the point cloud data of the rock wall surface after blasting excavation;

[0012] S2, calculate the center point coordinates and normal direction of the designed excavation face based on the design parameters and point cloud data, generate a feature plane, and fit the plane to the actual excavation face to obtain the fitted excavation face;

[0013] S3. In the fitted excavation surface, the blast holes are divided into a specific number of equal parts along the axial direction. The effective set of points with radial deviation in a specific range is selected. The ratio of the total length of the blast hole traces on the actual excavation surface to the total number of boreholes in the excavation surface is calculated to obtain the half-wall borehole ratio result.

[0014] Furthermore, step S3 specifically includes:

[0015] Divide the boreholes into a specific number of equal parts along the axial direction;

[0016] Using the fitted design excavation face as a benchmark, a deviation analysis was performed on the actual excavation face;

[0017] From the analyzed data, select the effective set of points where the radial deviation d is in the interval (-r, -nr), and calculate the ratio of the total length of the blast hole traces on the actual excavation surface to the total number of blast hole lengths on the excavation surface, where r is the design radius of the pre-splitting hole and n is a constant.

[0018] Furthermore, the step of dividing the borehole into a specific number of equal parts along the axial direction includes dividing the borehole into a specific number of equal parts along the axial direction using known pre-splitting borehole design parameters.

[0019] Furthermore, the formula for calculating the radial deviation d in the deviation analysis of the actual excavation face is as follows: Where: A, B, C, and D are the plane equation parameters of the designed excavation face; x0, y0, and z0 are the coordinates of a point on the actual excavation face; and d is the distance from a point on the actual excavation face to the plane equation parameters.

[0020] Furthermore, the formula for calculating the half-wall porosity is η= Where r is the design radius of the pre-cracked hole, n is a constant, and η is the half-wall porosity. To detect the total length of the borehole traces remaining on the slope surface in a section, This is to determine the total number of boreholes in meters on the slope of the detection section.

[0021] Furthermore, in step S1, obtaining the point cloud data of the rock wall surface after blasting excavation specifically includes: obtaining the point set data of the rock wall surface by using a total station to measure multiple times, and transmitting the point set data of the rock wall surface to a computer for internal processing, extracting the point cloud data of the area to be measured, performing preliminary point cloud data processing, and obtaining the point cloud data of the rock wall surface after blasting excavation.

[0022] Furthermore, the generation of the feature plane mainly includes the following steps: determining the parameters of the designed excavation face through known planar positioning coordinates, azimuth, inclination angle and the coordinates of the observation point, and generating the feature plane.

[0023] Furthermore, step S1 also includes preliminary point cloud data processing, the processing steps of which include: noise reduction processing; filtering point cloud data through non-connectivity terms; and filtering point cloud data through external isolated points.

[0024] Furthermore, step S2 specifically includes: determining the parameters of the designed excavation face, calculating the coordinates of the center point and the normal direction of the excavation face using the coordinates of the observation points and the inclination angle of the designed excavation face; and fitting the designed excavation face to the actual excavation face.

[0025] Based on the same concept, a rapid calculation system for half-wall porosity of pre-splitting blasting slope is also proposed, including at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, which are executed by the at least one processor to enable the at least one processor to execute the rapid calculation method for half-wall porosity of pre-splitting blasting slope described above.

[0026] Compared with the prior art, the beneficial effects of the present invention are: in the design of the excavation face, the half-wall porosity of the blasting excavation face is directly calculated by design parameters and observation point coordinates, without any human interference, which is fast and accurate. Attached Figure Description

[0027] Figure 1 This is a flowchart of a rapid calculation method for half-wall porosity in slope pre-splitting blasting, as described in Example 1.

[0028] Figure 2 This is a schematic diagram illustrating the calculation principle of the excavation face parameters in Example 1;

[0029] Figure 3This is a flowchart illustrating the specific implementation method in Example 2;

[0030] Figure 4 This is a side view of the slope pre-splitting blasting hole layout in Example 2;

[0031] Figure 5 This is a top view of the layout of the blast holes for pre-splitting blasting on the slope in Example 2;

[0032] Figure 6 This is a schematic diagram of a half-wall hole;

[0033] Figure 7 This is a cross-sectional view of the axis of the hole through the half-wall;

[0034] Figure label:

[0035] 1. Main blast hole; 2. Pre-splitting hole; 3. Explosive; 4. Plugging; 5. Rock slope; 6. Residual blast hole traces; 7. Radial deviation d. Detailed Implementation

[0036] The present invention will be further described in detail below with reference to experimental examples and specific embodiments. However, this should not be construed as limiting the scope of the above-mentioned subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0037] Example 1

[0038] A rapid calculation method for half-wall porosity in slope pre-splitting blasting, flowchart as follows: Figure 1 As shown, it includes the following steps:

[0039] S1, Obtain the design parameters of the blasting excavation face, including positioning coordinates, orientation, and inclination angle; Obtain the point cloud data of the rock wall surface after blasting excavation;

[0040] S2, calculate the center point coordinates and normal direction of the designed excavation face based on the design parameters and point cloud data, generate a feature plane, and fit the plane to the actual excavation face to obtain the fitted excavation face;

[0041] S3. In the fitted excavation surface, the blast holes are divided into a specific number of equal parts along the axial direction. The effective set of points with radial deviation in a specific range is selected. The ratio of the total length of the blast hole traces on the actual excavation surface to the total number of boreholes in the excavation surface is calculated to obtain the half-wall borehole ratio result.

[0042] Furthermore, step S2 specifically includes (1) determining the parameters of the designed excavation face, and calculating the coordinates of the center point and the normal direction of the excavation face using the coordinates of the observation points and the inclination angle of the designed excavation face; (2) fitting the designed excavation face to the actual excavation face. The principle diagram for calculating excavation face parameters is shown below. Figure 2 As shown.

[0043] Furthermore, step S3 specifically includes:

[0044] (1) Divide the boreholes into equal parts along the axial direction according to a specific number of parts; specifically, this includes dividing the boreholes into equal parts along the axial direction according to a specific number of parts using known pre-splitting borehole design parameters.

[0045] (2) Using the fitted design excavation face as a benchmark, a deviation analysis was performed on the actual excavation face. Where: A, B, C, and D are the plane equation parameters of the designed excavation face; x0, y0, and z0 are the coordinates of a point on the actual excavation face; and d is the distance from a point on the actual excavation face to the plane equation parameters.

[0046] (3) Select the effective point set where the radial deviation d is in the interval (-r, -nr), and calculate the ratio of the total length of the borehole traces on the actual excavation surface to the total number of borehole lengths on the excavation surface using the program, η= The half-porosity result is obtained. Here, r is the design radius of the pre-cracked hole, n is a constant (n = 0.8), and η is the half-wall porosity. To detect the total length of the borehole traces remaining on the slope surface in a section, This is to determine the total number of boreholes in meters on the slope of the detection section.

[0047] Furthermore, in step S1, obtaining the point cloud data of the rock wall surface after blasting excavation specifically includes: obtaining the point set data of the rock wall surface by using a total station to measure multiple times, and transmitting the point set data of the rock wall surface to a computer for internal processing, extracting the point cloud data of the area to be measured, performing preliminary point cloud data processing, and obtaining the point cloud data of the rock wall surface after blasting excavation.

[0048] Preferably, the point set data of the rock wall surface is imported into a computer with a point cloud processing program similar to RISCAN.PROR and a Windows 10 operating system. The point cloud data of the area to be measured is extracted and the preliminary point cloud data is processed. The preliminary point cloud data processing includes: (1) noise reduction processing to remove the rough and non-uniform surface of the curved model; noise reduction processing is performed by computer software; the purpose of noise reduction processing is to avoid noise points being introduced into the data during scanning or digitization. Generally, the rough and non-uniform surface of the collected curved model is regarded as "noise data". The source of noise may be slight vibration of the scanning equipment, rough surface of the object, etc. (2) filtering the point cloud through non-connection items, that is, filtering out the point bundles that deviate from the main point cloud; filtering the point cloud through non-connection items using computer software, that is, filtering out the point bundles that deviate from the main point cloud. (3) filtering the point cloud through external isolated points. Filtering the point cloud through external isolated points using computer software; external isolated points are caused by background objects such as desktops, walls, and supporting structures being scanned by the total station.

[0049] Furthermore, step S2 specifically includes the following steps: inputting the known planar positioning coordinates, orientation, inclination angle and point cloud data coordinates from step 1 into the computer, using the processing program to calculate the center point coordinates and normal direction of the designed excavation face, generating a feature plane, and fitting the plane to the actual excavation face.

[0050] Preferably, generating a feature plane mainly includes the following steps: determining the parameters of the design excavation face using known planar positioning coordinates, azimuth, inclination angle, and the coordinates of the observation point, and then generating the feature plane.

[0051] Fitting the feature plane to the actual excavation face involves establishing the feature plane of the designed excavation face through parameters and converting it into a data plane.

[0052] As a preferred option, step S3 specifically includes: calculating the deviation between the actual excavation face and the designed excavation face, screening the effective point set of residual blast hole traces whose deviation is within the interval (-r, -nr), where n is 0.8; calculating the ratio of the total length of the blast hole traces on the actual excavation face to the total number of boreholes on the excavation face, and obtaining the half-wall porosity result.

[0053] The beneficial effects of this invention are:

[0054] 1. During point cloud data processing, interference from noise, isolated points, and disconnected points is eliminated, resulting in a smoother, more accurate, and closer approximation of the actual excavation face. 2. In the excavation face design, unknown parameters are directly calculated from design parameters and observation point coordinates, then directly fitted by software, without any human intervention, resulting in high speed and accuracy. 3. Utilizing total station point scanning and automatic data recording avoids the manual reading errors of traditional optical instruments, enabling fast single-measurement speed, significantly improving field efficiency, and effectively enhancing both accuracy and speed.

[0055] Example 2

[0056] Example 2 uses the method of Example 1 to calculate the half-wall porosity of a pre-splitting blasting excavation for a water-related slope project. The specific implementation process is as follows: Figure 3 As shown.

[0057] Before the blasting excavation, the blasting team provided the coordinates of the excavation face. This slope is 7 meters high, 8 meters wide, 10 meters long, and has an inclination angle of 68°.

[0058] The rock face of a water-crossing slope after blasting and excavation was scanned multiple times using a total station to obtain point cloud data of the rock face.

[0059] The acquired point cloud data is imported into a computer with a point cloud processing program similar to RISCAN.PROR and a Windows 10 operating system. Point cloud data of the area to be tested is extracted and preliminary point cloud data processing is performed.

[0060] Specifically, it includes:

[0061] a. Convert the 3D point cloud model of the excavation face into geodetic coordinates using coordinate transformation methods;

[0062] b. Noise reduction processing using computer software;

[0063] The purpose of noise reduction is to prevent noise points from being introduced into the data during scanning or digitization.

[0064] The rough, non-uniform appearance on the collected curved surface model is generally regarded as "noise data".

[0065] The noise may originate from slight vibrations of the scanning equipment, rough surfaces of objects, or other reasons.

[0066] c. Use computer software to filter point clouds using non-connectivity terms, that is, filter out point bundles that deviate from the main point cloud.

[0067] d. Filter point clouds through external isolated points using computer software;

[0068] External isolated points are caused by the total station scanning background objects, such as desktops, walls, and supporting structures.

[0069] like Figure 4 The diagram shows the calculation of the design excavation face parameters. Using the known plane positioning coordinates, orientation, dip angle and the coordinates of the observation point, the coordinates of the center point of the design excavation face are calculated as (-14.5380, 6.5734, 0.1481) and the normal direction is (0.2042, 0, 0.7982). This feature plane is generated and fitted to the actual excavation face.

[0070] The design of the borehole section is divided into 100 equal parts along the axis. Each part is treated as a whole, and the point cloud data in each part is filtered to obtain point cloud data with negative deviation in a specific range.

[0071] The total number of equal divisions of the filtered point cloud data is multiplied by the axial length of each individual division to obtain the total length of the borehole traces remaining on the slope in the tested section. Calculate the total number of boreholes in meters on the slope of the inspection section. The half-wall porosity η is obtained.

[0072] Figure 4 , Figure 5This is a schematic diagram of the layout of blast holes for pre-splitting blasting on a slope. Measurement results show that the longest half-hole length is 7.45m, and the shortest half-hole length is 0.43m. Figure 5 The diagram shows the half-wall permeability of each borehole on the excavated slope face, arranged from left to right: the first borehole has a half-wall permeability of 87%, the second borehole 87%, the third borehole 82%, the fourth borehole 94%, the fifth borehole 79%, the sixth borehole 74%, the seventh borehole 67%, the eighth borehole 69%, and the ninth borehole 50%.

[0073] The maximum half-wall porosity was 94%, the minimum half-wall porosity was 50%, and the average η was 76.5%. A schematic diagram of the half-wall porosity is shown below. Figure 6 As shown; a cross-sectional view of the axis of the half-wall hole is shown below. Figure 7 As shown.

[0074] Finally, it should be noted that the embodiments described in the above description are merely preferred practices of the invention and should not be construed as limiting the scope of the invention. Equivalent substitutions for the technical solutions described in the foregoing embodiments do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the invention, and all such substitutions should be covered within the scope of the claims and specification of the invention.

Claims

1. A rapid calculation method for the half-wall porosity of slope pre-splitting blasting, characterized in that, Includes the following steps: S1, Obtain the design parameters of the blasting excavation face, including the positioning coordinates, orientation, and inclination angle; Obtain point cloud data of the rock wall surface after blasting and excavation; S2, calculate the center point coordinates and normal direction of the designed excavation face based on the design parameters and point cloud data, generate a feature plane, and fit the plane to the actual excavation face to obtain the fitted excavation face; S3. In the fitted excavation face, the blast holes are divided equally along the axial direction according to a set number. The effective point set with radial deviation in a specific range is selected. The ratio of the total length of the blast hole traces on the actual excavation face to the total number of boreholes in the excavation face is calculated to obtain the half-wall porosity result. The specific range is (-r, -nr), where r is the design radius of the pre-splitting hole and n is a constant.

2. The rapid calculation method for half-wall porosity in slope pre-splitting blasting as described in claim 1, characterized in that, Step S3 specifically includes: Divide the boreholes into equal numbers along the axial direction according to a predetermined number; Using the fitted design excavation face as a benchmark, a deviation analysis was performed on the actual excavation face; From the analyzed data, select the effective set of points where the radial deviation d is in the interval (-r, -nr), and calculate the ratio of the total length of the blast hole traces on the actual excavation surface to the total number of blast hole lengths on the excavation surface, where r is the design radius of the pre-splitting hole and n is a constant.

3. The rapid calculation method for half-wall porosity in slope pre-splitting blasting as described in claim 2, characterized in that, The step of dividing the boreholes into equal parts along the axial direction according to a set number includes dividing the boreholes into equal parts along the axial direction according to a set number using known pre-splitting hole design parameters.

4. The rapid calculation method for half-wall porosity in slope pre-splitting blasting as described in claim 2, characterized in that, The formula for calculating the radial deviation d in the deviation analysis of the actual excavation face is as follows: Where: A, B, C, and D are the plane equation parameters of the designed excavation face; x0, y0, and z0 are the coordinates of a point on the actual excavation face; and d is the distance from a point on the actual excavation face to the designed excavation face.

5. The rapid calculation method for half-wall porosity in slope pre-splitting blasting as described in claim 2, characterized in that, The formula for calculating the half-wall porosity is η= Where r is the design radius of the pre-cracked hole, n is a constant, and η is the half-wall porosity. To detect the total length of the borehole traces remaining on the slope surface in a section, This is to determine the total number of boreholes in meters on the slope of the detection section.

6. The rapid calculation method for half-wall porosity in slope pre-splitting blasting as described in claim 1, characterized in that, In step S1, obtaining the point cloud data of the rock wall after blasting excavation specifically includes: obtaining the point set data of the rock wall after multiple measurements using a total station, transmitting the point set data of the rock wall to a computer for internal processing, extracting the point cloud data of the area to be measured, performing preliminary point cloud data processing, and obtaining the point cloud data of the rock wall after blasting excavation.

7. The rapid calculation method for half-wall porosity in slope pre-splitting blasting as described in claim 1, characterized in that, The generation of the feature plane mainly includes the following steps: determining the parameters of the designed excavation face using the known planar positioning coordinates, azimuth, inclination angle, and coordinates of the observation point, and then generating the feature plane.

8. The rapid calculation method for half-wall porosity in slope pre-splitting blasting as described in claim 1, characterized in that, Step S1 also includes preliminary point cloud data processing, which includes: noise reduction; filtering point cloud data through non-connectivity items; and filtering point cloud data through external isolated points.

9. The rapid calculation method for half-wall porosity in slope pre-splitting blasting as described in claim 1, characterized in that, Step S2 specifically includes: determining the parameters of the designed excavation face, calculating the coordinates of the center point and the normal direction of the excavation face using the coordinates of the observation points and the inclination angle of the designed excavation face; and fitting the designed excavation face to the actual excavation face.

10. A rapid calculation system for the half-wall porosity of slope pre-splitting blasting, characterized in that, It includes at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, which, when executed by the at least one processor, enable the at least one processor to perform a rapid calculation method for half-wall porosity of slope pre-splitting blasting according to any one of claims 1 to 9.

Images