A method for extracting crack degradation image contours for PFC software model

Abstract

The present invention discloses a method for extracting crack degradation image contours for a PFC software model, relates to the field of structural engineering, and solves the problem of poor resource utilization efficiency in the existing method for extracting crack degradation image contours for a PFC software model. The method comprises the following steps: S1: obtaining PFC model files of a target PFC engineering model at multiple different time nodes, and creating a three-dimensional coordinate system for each PFC model file to obtain model coordinate system creation data; S2: performing particle edge analysis on a first characteristic particle in each model coordinate system to obtain particle edge analysis data; S3: extracting crack contours for each PFC model file, and performing crack degradation monitoring according to the extraction result to obtain crack degradation monitoring data; and S4: performing degradation assessment on the target PFC engineering model according to the crack degradation monitoring data. The present invention can realize faster crack contour extraction and improve the utilization efficiency of model computing resources.

Description

Technical Field

[0001] The invention belongs to the field of structural engineering, relates to image analysis technology, and specifically is a method for extracting crack degradation image contours for a PFC software model. Background Art

[0002] PFC (Particle Flow Code) is a numerical simulation technology based on the discrete element method. It is mainly used to study the mechanical properties of granular materials, especially in geotechnical engineering. The core idea of ​​PFC is to divide the object into hundreds to tens of thousands of representative particle units. Each particle has its own position and velocity, and the overall continuous behavior is inferred through local simulation. The existing crack degradation image contour extraction method for the PFC software model has the following specific defects when performing contour extraction and degradation assessment:

[0003] 1. The existing PFC software model crack degradation image contour extraction method needs to extract multiple features such as shape features, texture features, and color features to identify the contour boundary during contour extraction. The extraction of these features requires the simultaneous execution of multiple algorithms, which makes the complexity of each algorithm superimposed, thus consuming a large amount of computing resources, which is not conducive to deployment in a computer environment with limited computing power;

[0004] 2. The existing method for extracting the contour of crack degradation images of PFC software models can only output a single numerical value of the crack parameters in the real-time model, and cannot combine the crack contour images of historical periods to conduct a comprehensive assessment of engineering model degradation, which results in low model utilization value.

[0005] To this end, we propose a method for extracting crack degradation image contours for the particle flow program PFC software model. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for extracting crack degradation image contours for a particle flow program PFC software model, and the present invention aims to improve the efficiency of the crack degradation image contour extraction process.

[0007] In order to achieve the above object, the present invention adopts the following technical solution: a method for extracting the contour of crack degradation image of PFC software model, comprising the following specific steps:

[0008] Step S1: Obtain a target PFC engineering model, save the target PFC engineering models at multiple different time nodes into files, obtain multiple PFC model files, create a three-dimensional coordinate system for each PFC model file, and obtain model coordinate system creation data;

[0009] Step S2: Create data through the model coordinate system to monitor the particle edge of each first characteristic particle to obtain the contact coordinate distance difference, and perform distance numerical analysis on each contact coordinate distance difference, and divide the multiple first characteristic particles into crack edge particles and non-crack edge particles according to the analysis results to obtain particle edge analysis data;

[0010] Step S3: extracting and reconstructing the crack contour of each PFC model file according to the particle edge analysis data and the model coordinate system creation data, obtaining multiple crack contour three-dimensional models, and dividing each crack contour three-dimensional model into a number of crack model slice images, and performing crack degradation analysis on each crack model slice image to obtain the crack area degradation coefficient, crack length degradation coefficient and crack intersection degradation coefficient respectively, and obtain crack degradation monitoring data;

[0011] Step S4: Obtain the model gap degradation assessment coefficient by analyzing the crack degradation monitoring data, obtain the model gap degradation assessment coefficient threshold and perform numerical comparison with the model gap degradation assessment coefficient, perform degradation assessment on the target PFC engineering model according to the numerical comparison result, and issue a gap degradation warning according to the assessment result.

[0012] Furthermore, the step S1 further includes the following specific steps:

[0013] Step S11: Obtain a target PFC project model by using a PFC model corresponding to the target project created by the PFC software;

[0014] Step S12: saving the target PFC engineering models at multiple different time nodes to obtain multiple PFC model files, and naming the saved multiple PFC model files as B1 model file to Bn model file in the order of the saving time nodes;

[0015] Step S13: Create a model coordinate system for the B1 model file to obtain the B1 model coordinate system;

[0016] Step S14: creating model coordinate systems for the B2 model file to the Bn model file respectively, and obtaining the B1 model coordinate system to the Bn model coordinate system;

[0017] Step S15: define the B1 model coordinate system to the Bn model coordinate system as model coordinate system creation data.

[0018] Furthermore, the step S13 further includes the following specific steps:

[0019] Step S131: Open the B1 model file in the PFC software to obtain the B1 engineering model. In the B1 engineering model, use a plurality of first characteristic particles to fill the crack area in the B1 engineering model, and use a plurality of second characteristic particles to fill the non-crack area in the B1 engineering model to obtain the B1 engineering filling model;

[0020] Step S132: randomly select a model vertex in the B1 engineering filling model as a feature coordinate point, randomly draw a straight line through the feature coordinate point to obtain a first model feature line, and mark the plane where the first model feature line is located as the first feature plane, and in the first feature plane, draw a straight line perpendicular to the first model feature line through the feature coordinate point to obtain a second model feature line, and draw a straight line perpendicular to the first feature plane through the feature coordinate point to obtain a third model feature line;

[0021] Step S133: In the B1 engineering filling model, the characteristic coordinate point is marked as the coordinate origin, the first model characteristic line is marked as the coordinate x-axis, the second model characteristic line is marked as the coordinate y-axis, the third model characteristic line is marked as the coordinate z-axis, and the three-dimensional rectangular coordinate system composed of the coordinate origin, the coordinate x-axis, the coordinate y-axis and the coordinate z-axis is named the B1 model coordinate system.

[0022] Step S134: in the B1 model coordinate system, the geometric center corresponding to each characteristic particle is obtained respectively, and the geometric center corresponding to each characteristic particle is marked as a coordinate point in the B1 model coordinate system.

[0023] Furthermore, the step S2 further includes the following specific steps:

[0024] Step S21: Acquire model coordinate system creation data, and acquire B1 model coordinate system to Bn model coordinate system respectively according to the model coordinate system creation data;

[0025] Step S22: performing particle edge analysis on the first characteristic particle in the B1 model coordinate system, and obtaining B1 particle edge division data according to the analysis result;

[0026] Step S23: respectively acquiring the particle edge division data corresponding to the B2 model coordinate system to the Bn model coordinate system, and obtaining the B2 particle edge division data to the Bn particle edge division data;

[0027] Step S24: defining B1 particle edge division data to Bn particle edge division data as particle edge analysis data;

[0028] The step S22 further includes the following specific steps:

[0029] Step S221: selecting a sample characteristic particle from a plurality of first characteristic particles in the B1 model coordinate system;

[0030] Step S222: acquiring the coordinate points corresponding to the characteristic particles of the sample in the B1 model coordinate system to obtain the coordinates of the sample particles;

[0031] Step S223: in the B1 model coordinate system, characteristic particles in contact with the sample characteristic particles are acquired to obtain a plurality of characteristic contact particles, and the acquired plurality of characteristic contact particles are named as the first characteristic contact particle to the ath characteristic contact particle respectively;

[0032] Step S224: respectively acquiring the coordinates corresponding to the first characteristic contact particle to the ath characteristic contact particle in the B1 model coordinate system to obtain the first characteristic contact coordinates to the ath characteristic contact coordinates;

[0033] Step S225: calculating the contact coordinate distance difference corresponding to the sample characteristic particle from the first characteristic contact coordinate to the ath characteristic contact coordinate and the sample particle coordinate;

[0034] The contact coordinate distance difference corresponding to the characteristic particles of the sample is calculated. The specific formula is as follows:

[0035] ;

[0036] Where Jjc is the contact coordinate distance difference corresponding to the characteristic particles of the sample, (x t ,y t ,z t ) is the sample particle coordinate, (x i ,y i ,z i ) is the i-th characteristic contact coordinate, a is the quantity value corresponding to the characteristic contact particle;

[0037] Step S226: acquiring the contact coordinate distance difference corresponding to each first characteristic particle respectively to obtain a plurality of contact coordinate distance differences;

[0038] Step S227: obtaining the reference coordinate distance difference, calculating the difference between each basic coordinate distance difference and the reference coordinate distance difference, and taking the absolute value of the obtained difference to obtain the distance deviation of multiple coordinate points;

[0039] Step S228: obtaining a coordinate point distance deviation threshold, numerically comparing each coordinate point distance deviation with the coordinate point distance deviation threshold, and dividing the first characteristic particles into crack edge particles and non-crack edge particles according to the numerical comparison result, to obtain B1 particle edge division data;

[0040] The details are as follows:

[0041] If the coordinate point distance deviation is greater than or equal to the coordinate point distance deviation threshold, the corresponding first characteristic particle is classified as a crack edge particle;

[0042] If the coordinate point distance deviation is less than the coordinate point distance deviation threshold, the corresponding first characteristic particle is classified as a non-crack edge particle.

[0043] Furthermore, the step S3 further includes the following specific steps:

[0044] Step S31: acquiring model coordinate system creation data, acquiring B1 model coordinate system to Bn model coordinate system respectively according to the model coordinate system creation data, acquiring particle edge analysis data, and acquiring B1 particle edge division data to Bn particle edge division data respectively according to the particle edge analysis data;

[0045] Step S32: extracting the model crack contour according to the B1 particle edge division data to the Bn particle edge division data, and obtaining the B1 crack contour three-dimensional model to the Bn crack contour three-dimensional model;

[0046] Step S33: Slicing the B1 crack contour three-dimensional model to obtain the first crack model slice image to the cth crack model slice image corresponding to the B1 crack contour three-dimensional model;

[0047] Step S34: respectively acquiring the first crack model slice image to the cth crack model slice image corresponding to the B2 crack contour three-dimensional model to the Bn crack contour three-dimensional model;

[0048] Step S35: naming the first crack model slice image in the B1 crack contour three-dimensional model as the Q1 model slice image, naming the first crack model slice image in the B2 crack contour three-dimensional model as the Q2 model slice image, and so on, naming the first crack model slice image in the Bn crack contour three-dimensional model as the Qn model slice image;

[0049] Step S36: monitoring the crack region area change from the first crack model slice image to the cth crack model slice image, and performing a comprehensive analysis on the monitoring results to obtain the first crack region area degradation coefficient;

[0050] Step S37: monitoring the crack lengths of the first crack model slice image to the cth crack model slice image, and comprehensively analyzing the monitoring results to obtain a crack length degradation coefficient;

[0051] Step S38: monitoring the number of crack intersections from the first crack model slice image to the cth crack model slice image, and performing a comprehensive analysis on the monitoring results to obtain a crack intersection degradation coefficient;

[0052] Step S39: defining the crack area degradation coefficient, the crack length degradation coefficient and the crack intersection degradation coefficient as crack degradation monitoring data;

[0053] The step S33 further includes the following specific steps:

[0054] Step S331: Mark a number of feature cutting points with equal intervals on the coordinate z axis in the B1 model coordinate system to obtain the first feature cutting point to the cth feature cutting point;

[0055] Step S332: Draw a plane perpendicular to the coordinate y-axis through the first feature cutting point to the c-th feature cutting point to obtain the first feature cutting plane to the c-th feature cutting plane, and acquire images of the model slices of the B1 crack contour three-dimensional model from the first feature cutting plane to the c-th feature cutting plane to obtain the first crack model slice image to the c-th crack model slice image.

[0056] Furthermore, the step S32 further includes the following specific steps:

[0057] Step S321: acquiring crack edge particles of the B1 engineering filling model according to the B1 particle edge division data, respectively acquiring the three-dimensional coordinates of each crack edge particle in the B1 model coordinate system, and obtaining a plurality of crack edge three-dimensional coordinates;

[0058] Step S322: constructing the acquired three-dimensional coordinates of the multiple crack edges into a point cloud data set, and using a curve fitting algorithm to extract the contour of the point cloud data set to obtain the B1 crack contour;

[0059] Step S323: Line drawing is performed on the B1 crack contour to obtain a plurality of contour drawing lines, and the plurality of contour drawing lines are connected by an image tool to obtain a crack contour three-dimensional model corresponding to the B1 engineering filling model, and the model is named B1 crack contour three-dimensional model;

[0060] Step S324: respectively acquiring the three-dimensional models of the crack contours corresponding to the B2 engineering filling model to the Bn engineering filling model, and obtaining the B2 crack contour three-dimensional model to the Bn crack contour three-dimensional model.

[0061] Furthermore, the step S36 further includes the following specific steps:

[0062] Step S361: acquiring the area value of the first characteristic particle coverage area in the Q1 model slice image to obtain the area value of the Q1 crack area, acquiring the area value of the first characteristic particle coverage area in the Q2 model slice image to obtain the area value of the Q2 crack area, and so on, acquiring the area value of the first characteristic particle coverage area in the Qn model slice image to obtain the area value of the Qn crack area;

[0063] Step S362: Calculate the area value of the crack region Q1 to the area value of the crack region Qn to obtain the first crack region area degradation coefficient;

[0064] The area degradation coefficient of the first crack region is calculated, and the formula is as follows:

[0065] ;

[0066] Among them, Scm1 is the area degradation coefficient of the first crack region, Smq i is the area value of the Qi crack region, Smq i-1 is the area value of the Qi-1 crack region;

[0067] Step S363: monitoring the crack region area change of the second crack model slice image to the c-th crack model slice image respectively, and obtaining the second crack region area degradation coefficient to the c-th crack region area degradation coefficient;

[0068] Step S364: Calculate the average of the first crack region area degradation coefficient to the cth crack region area degradation coefficient to obtain the crack region area degradation coefficient.

[0069] Furthermore, the step S37 further includes the following specific steps:

[0070] Step S371: Acquire the length value of the contour drawing line in the Q1 model slice image to obtain the Q1 contour line length value, acquire the length value of the contour drawing line in the Q2 model slice image to obtain the Q2 contour line length value, and so on, acquire the length value of the contour drawing line in the Qn model slice image to obtain the Qn contour line length value;

[0071] Step S372: obtaining a crack length degradation coefficient corresponding to the first crack model slice image by calculating the Q1 contour line length value to the Qn contour line length value;

[0072] The crack length degradation coefficient corresponding to the first crack model slice image is calculated, and the formula is as follows:

[0073] ;

[0074] Wherein, Clx is the crack length degradation coefficient corresponding to the first crack model slice image, Clq i is the length of Qi contour line, Clq i-1 is the length value of the Qi-1 contour line, and n is the number value corresponding to the slice image of the first crack model;

[0075] Step S373: respectively acquiring the crack length degradation coefficients corresponding to the second crack model slice image to the cth crack model slice image to obtain a plurality of crack length degradation coefficients;

[0076] Step S374: Calculate the average of the multiple crack length degradation coefficients obtained to obtain the crack length degradation coefficient.

[0077] Furthermore, the step S38 further includes the following specific steps:

[0078] Step S381: Acquire the number of intersection points of the contour drawing lines in the slice image of the Q1 model to obtain the number of intersection points of the Q1 contour lines, acquire the number of intersection points of the contour drawing lines in the slice image of the Q2 model to obtain the number of intersection points of the Q2 contour lines, and so on, acquire the number of intersection points of the contour drawing lines in the slice image of the Qn model to obtain the number of intersection points of the Qn contour lines;

[0079] Step S382: obtaining the crack intersection degradation coefficient corresponding to the first crack model slice image by calculating the number of Q1 contour line intersections to the number of Qn contour line intersections;

[0080] The crack intersection degradation coefficient corresponding to the first crack model slice image is calculated, and the formula is as follows:

[0081] ;

[0082] Among them, Jdx is the crack intersection degradation coefficient corresponding to the first crack model slice image, Jdq i is the number of intersection points of Qi contour lines, Jdq i-1 is the number of intersections of the Qi-1 contour line, and n is the number value corresponding to the slice image of the first crack model;

[0083] Step S383: acquiring the crack intersection degradation coefficients corresponding to the second crack model slice image to the cth crack model slice image to obtain a plurality of crack intersection degradation coefficients;

[0084] Step S384: Calculate the average of the obtained multiple crack intersection degradation coefficients to obtain the crack intersection degradation coefficient.

[0085] Furthermore, the step S4 further includes the following specific steps:

[0086] Step S41: obtaining crack degradation monitoring data, and obtaining crack area degradation coefficient, crack length degradation coefficient and crack intersection degradation coefficient respectively according to the crack degradation monitoring data;

[0087] Step S42: Calculating the crack area degradation coefficient, the crack length degradation coefficient and the crack intersection degradation coefficient to obtain the model crack degradation assessment coefficient;

[0088] The model degradation assessment coefficient is calculated, and the specific formula is as follows:

[0089] ;

[0090] Among them, Mlp is the model degradation assessment coefficient, Sml is the crack area degradation coefficient, Cdl is the crack length degradation coefficient, and Jdl is the crack intersection degradation coefficient;

[0091] Step S43: obtaining a model gap degradation assessment coefficient threshold, performing a numerical comparison between the model gap degradation assessment coefficient and the model gap degradation assessment coefficient threshold, performing a degradation assessment on the target PFC engineering model according to the numerical comparison result, and issuing a gap degradation warning according to the assessment result;

[0092] The step S43 further includes the following specific steps:

[0093] Step S431: respectively obtaining a crack region area degradation coefficient threshold, a crack length degradation coefficient threshold, and a crack intersection degradation coefficient threshold;

[0094] Step S432: Calculating the crack area degradation coefficient threshold, the crack length degradation coefficient threshold, and the crack intersection degradation coefficient threshold to obtain a model crack degradation assessment coefficient threshold;

[0095] Step S433: when the model gap degradation assessment coefficient is greater than or equal to the model gap degradation assessment coefficient threshold, the target PFC engineering model is assessed to be in an abnormal degradation state, and an abnormal degradation warning is issued;

[0096] Step S434: When the model gap degradation assessment coefficient is less than the model gap degradation assessment coefficient threshold, the assessment target PFC engineering model is in a normal degradation state, and no abnormal degradation warning is issued.

[0097] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0098] 1. The present invention creates data through a model coordinate system to monitor the particle edge of each first characteristic particle to obtain the contact coordinate distance difference, and performs distance numerical analysis on each contact coordinate distance difference. According to the analysis results, multiple first characteristic particles are divided into crack edge particles and non-crack edge particles, which can greatly save the computing resources of the deployment environment, achieve faster contour extraction, and ensure the use efficiency of computing resources;

[0099] 2. The present invention divides the three-dimensional model of the crack contour at different monitoring time points into a number of crack model slice images, and performs crack degradation analysis on each crack model slice image to respectively obtain the crack area degradation coefficient, crack length degradation coefficient and crack intersection degradation coefficient, and performs degradation assessment on the target PFC engineering model according to the crack area degradation coefficient, crack length degradation coefficient and crack intersection degradation coefficient, which can improve the application value of crack model contour extraction and enhance the PFC software model's ability to assess crack degradation. BRIEF DESCRIPTION OF THE DRAWINGS

[0100] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0101] Figure 1 It is a diagram of the implementation steps of the present invention;

[0102] Figure 2 It is a schematic diagram of the B1 model coordinate system of the present invention;

[0103] Figure 3 Schematic diagram of characteristic contact particles of the present invention. DETAILED DESCRIPTION

[0104] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0105] Example 1, please refer to Figure 1 The present invention provides a technical solution: a method for extracting the contour of a crack degradation image of a PFC software model, comprising the following specific steps:

[0106] Step S1: Obtain a target PFC engineering model, save the target PFC engineering models at multiple different time nodes into files, obtain multiple PFC model files, create a three-dimensional coordinate system for each PFC model file, and obtain model coordinate system creation data;

[0107] The step S1 further includes the following specific steps:

[0108] Step S11: Obtain a target PFC project model by using a PFC model corresponding to the target project created by the PFC software;

[0109] It should be noted here that:

[0110] In this application, the target project involved here is the model for extracting the contour of crack degradation image in this application;

[0111] Step S12: saving the target PFC engineering models at multiple different time nodes to obtain multiple PFC model files, and naming the saved multiple PFC model files as B1 model file to Bn model file in the order of the saving time nodes;

[0112] It should be noted here that:

[0113] In the present application, B referred to herein is an identifier corresponding to a PFC model file, n is the number of PFC model files stored, and n is an integer greater than 0;

[0114] In this application, the model parameters corresponding to the target PFC engineering model at different time nodes are all different, and the model parameters involved here include but are not limited to stress, strain, crack length, crack width and external force load;

[0115] In this application, the multiple model files involved here are respectively static models corresponding to the target PFC engineering model at different time points;

[0116] Step S13: Create a model coordinate system for the B1 model file to obtain the B1 model coordinate system;

[0117] The step S13 further includes the following specific steps:

[0118] Step S131: Open the B1 model file in the PFC software to obtain the B1 engineering model. In the B1 engineering model, use a plurality of first characteristic particles to fill the crack area in the B1 engineering model, and use a plurality of second characteristic particles to fill the non-crack area in the B1 engineering model to obtain the B1 engineering filling model;

[0119] It should be noted here that:

[0120] In the present application, the first characteristic particles and the second characteristic particles involved herein have different particle sizes in the B1 engineering model;

[0121] Step S132: randomly select a model vertex in the B1 engineering filling model as a feature coordinate point, randomly draw a straight line through the feature coordinate point to obtain a first model feature line, and mark the plane where the first model feature line is located as the first feature plane, and in the first feature plane, draw a straight line perpendicular to the first model feature line through the feature coordinate point to obtain a second model feature line, and draw a straight line perpendicular to the first feature plane through the feature coordinate point to obtain a third model feature line;

[0122] Step S133: Please refer to Figure 2In the B1 engineering filling model, the feature coordinate point is marked as the coordinate origin, the first model feature line is marked as the coordinate x-axis, the second model feature line is marked as the coordinate y-axis, the third model feature line is marked as the coordinate z-axis, and the three-dimensional rectangular coordinate system composed of the coordinate origin, the coordinate x-axis, the coordinate y-axis and the coordinate z-axis is named the B1 model coordinate system.

[0123] Step S134: in the B1 model coordinate system, the geometric center corresponding to each characteristic particle is obtained respectively, and the geometric center corresponding to each characteristic particle is marked as a coordinate point in the B1 model coordinate system;

[0124] It should be noted here that:

[0125] In the present application, the characteristic particles involved herein include first characteristic particles and second characteristic particles;

[0126] Step S14: creating model coordinate systems for the B2 model file to the Bn model file respectively, and obtaining the B1 model coordinate system to the Bn model coordinate system;

[0127] Step S15: defining the B1 model coordinate system to the Bn model coordinate system as model coordinate system creation data;

[0128] Step S2: performing particle edge analysis on the first characteristic particle in each model coordinate system according to the model coordinate system creation data to obtain particle edge analysis data;

[0129] The step S2 further includes the following specific steps:

[0130] Step S21: Acquire model coordinate system creation data, and acquire B1 model coordinate system to Bn model coordinate system respectively according to the model coordinate system creation data;

[0131] Step S22: performing particle edge analysis on the first characteristic particle in the B1 model coordinate system, and obtaining B1 particle edge division data according to the analysis result;

[0132] The step S22 further includes the following specific steps:

[0133] Step S221: selecting a sample characteristic particle from a plurality of first characteristic particles in the B1 model coordinate system;

[0134] Step S222: acquiring the coordinate points corresponding to the characteristic particles of the sample in the B1 model coordinate system to obtain the coordinates of the sample particles;

[0135] Step S223: Please refer to Figure 3, in the B1 model coordinate system, the characteristic particles in contact with the sample characteristic particles are acquired to obtain a plurality of characteristic contact particles, and the acquired plurality of characteristic contact particles are named as the first characteristic contact particle to the ath characteristic contact particle respectively;

[0136] It should be noted here that:

[0137] In the present application, a referred to herein is the quantity value corresponding to the characteristic contact particles, and a is an integer greater than 0;

[0138] Step S224: respectively acquiring the coordinates corresponding to the first characteristic contact particle to the ath characteristic contact particle in the B1 model coordinate system to obtain the first characteristic contact coordinates to the ath characteristic contact coordinates;

[0139] Step S225: calculating the contact coordinate distance difference corresponding to the sample characteristic particle from the first characteristic contact coordinate to the ath characteristic contact coordinate and the sample particle coordinate;

[0140] The contact coordinate distance difference corresponding to the characteristic particles of the sample is calculated. The specific formula is as follows:

[0141] ;

[0142] Where Jjc is the contact coordinate distance difference corresponding to the characteristic particles of the sample, (x t ,y t ,z t ) is the sample particle coordinate, (x i ,y i ,z i ) is the i-th characteristic contact coordinate, a is the quantity value corresponding to the characteristic contact particle;

[0143] It should be noted here that:

[0144] In the present application, the i-th characteristic contact coordinate referred to herein may be any characteristic contact coordinate from the first characteristic contact coordinate to the a-th characteristic contact coordinate;

[0145] Step S226: acquiring the contact coordinate distance difference corresponding to each first characteristic particle respectively to obtain a plurality of contact coordinate distance differences;

[0146] Step S227: obtaining the reference coordinate distance difference, calculating the difference between each basic coordinate distance difference and the reference coordinate distance difference, and taking the absolute value of the obtained difference to obtain the distance deviation of multiple coordinate points;

[0147] It should be noted here that:

[0148] The reference coordinate distance difference involved here is the coordinate point distance deviation between any two first characteristic particles;

[0149] Step S228: obtaining a coordinate point distance deviation threshold, numerically comparing each coordinate point distance deviation with the coordinate point distance deviation threshold, and dividing the first characteristic particles into crack edge particles and non-crack edge particles according to the numerical comparison result, to obtain B1 particle edge division data;

[0150] It should be noted here that:

[0151] In this application, the coordinate point distance deviation threshold involved here is the maximum coordinate point distance deviation corresponding to the non-crack edge particles;

[0152] The details are as follows:

[0153] Step S2281: if the coordinate point distance deviation is greater than or equal to the coordinate point distance deviation threshold, the corresponding first characteristic particle is classified as a crack edge particle;

[0154] Step S2282: if the coordinate point distance deviation is less than the coordinate point distance deviation threshold, the corresponding first characteristic particle is classified as a non-crack edge particle;

[0155] Step S23: respectively acquiring the particle edge division data corresponding to the B2 model coordinate system to the Bn model coordinate system, and obtaining the B2 particle edge division data to the Bn particle edge division data;

[0156] Step S24: defining B1 particle edge segmentation data to Bn particle edge segmentation data as particle edge analysis data.

[0157] Step S3: extracting crack contours for each PFC model file according to the particle edge analysis data and the model coordinate system creation data, and performing crack degradation monitoring according to the extraction results to obtain crack degradation monitoring data;

[0158] The step S3 further includes the following specific steps:

[0159] Step S31: acquiring model coordinate system creation data, acquiring B1 model coordinate system to Bn model coordinate system respectively according to the model coordinate system creation data, acquiring particle edge analysis data, and acquiring B1 particle edge division data to Bn particle edge division data respectively according to the particle edge analysis data;

[0160] Step S32: extracting the model crack contour according to the B1 particle edge division data to the Bn particle edge division data, and obtaining the B1 crack contour three-dimensional model to the Bn crack contour three-dimensional model;

[0161] The step S32 further includes the following specific steps:

[0162] Step S321: acquiring crack edge particles of the B1 engineering filling model according to the B1 particle edge division data, respectively acquiring the three-dimensional coordinates of each crack edge particle in the B1 model coordinate system, and obtaining a plurality of crack edge three-dimensional coordinates;

[0163] Step S322: constructing the acquired three-dimensional coordinates of the multiple crack edges into a point cloud data set, and using a curve fitting algorithm to extract the contour of the point cloud data set to obtain the B1 crack contour;

[0164] Step S323: Line drawing is performed on the B1 crack contour to obtain a plurality of contour drawing lines, and the plurality of contour drawing lines are connected by an image tool to obtain a crack contour three-dimensional model corresponding to the B1 engineering filling model, and the model is named B1 crack contour three-dimensional model;

[0165] Step S324: respectively acquiring the fracture contour three-dimensional models corresponding to the B2 engineering filling model to the Bn engineering filling model, and obtaining the B2 fracture contour three-dimensional model to the Bn fracture contour three-dimensional model;

[0166] Step S33: Slice the B1 crack contour three-dimensional model to obtain the first crack model slice image to the cth crack model slice image corresponding to the B1 crack contour three-dimensional model;

[0167] The step S33 further includes the following specific steps:

[0168] Step S331: Mark a number of feature cutting points with equal intervals on the coordinate z axis in the B1 model coordinate system to obtain the first feature cutting point to the cth feature cutting point;

[0169] Step S332: draw planes perpendicular to the coordinate y-axis through the first characteristic cutting point to the c-th characteristic cutting point respectively, obtain the first characteristic cutting plane to the c-th characteristic cutting plane, and acquire images of the model slices of the B1 crack contour three-dimensional model from the first characteristic cutting plane to the c-th characteristic cutting plane to obtain the first crack model slice images to the c-th crack model slice images;

[0170] Step S34: respectively acquiring the first crack model slice image to the cth crack model slice image corresponding to the B2 crack contour three-dimensional model to the Bn crack contour three-dimensional model;

[0171] It should be noted here that:

[0172] In the present application, the distance intervals of the characteristic cutting points in different model coordinate systems are equal, for example: the first crack model slice image in the B1 crack contour three-dimensional model to the Bn crack contour three-dimensional model has the same slice position in the model;

[0173] Step S35: naming the first crack model slice image in the B1 crack contour three-dimensional model as the Q1 model slice image, naming the first crack model slice image in the B2 crack contour three-dimensional model as the Q2 model slice image, and so on, naming the first crack model slice image in the Bn crack contour three-dimensional model as the Qn model slice image;

[0174] Step S36: monitoring the crack region area change from the first crack model slice image to the cth crack model slice image, and performing a comprehensive analysis on the monitoring results to obtain the first crack region area degradation coefficient;

[0175] The step S36 further includes the following specific steps:

[0176] Step S361: acquiring the area value of the first characteristic particle coverage area in the Q1 model slice image to obtain the area value of the Q1 crack area, acquiring the area value of the first characteristic particle coverage area in the Q2 model slice image to obtain the area value of the Q2 crack area, and so on, acquiring the area value of the first characteristic particle coverage area in the Qn model slice image to obtain the area value of the Qn crack area;

[0177] Step S362: Calculate the area value of the crack region Q1 to the area value of the crack region Qn to obtain the first crack region area degradation coefficient;

[0178] The area degradation coefficient of the first crack region is calculated, and the formula is as follows:

[0179] ;

[0180] Among them, Scm1 is the area degradation coefficient of the first crack region, Smq i is the area value of the Qi crack region, Smq i-1 is the area value of the Qi-1 crack region;

[0181] It should be noted here that:

[0182] In the present application, the Qi crack region area value involved here can be any crack region area value from the Q1 crack region area value to the Qn crack region area value.

[0183] Step S363: monitoring the crack region area change of the second crack model slice image to the c-th crack model slice image respectively, and obtaining the second crack region area degradation coefficient to the c-th crack region area degradation coefficient;

[0184] Step S364: Calculate the average of the first crack region area degradation coefficient to the cth crack region area degradation coefficient to obtain the crack region area degradation coefficient;

[0185] Step S37: monitoring the crack lengths of the first crack model slice image to the cth crack model slice image, and comprehensively analyzing the monitoring results to obtain a crack length degradation coefficient;

[0186] The step S37 further includes the following specific steps:

[0187] Step S371: Acquire the length value of the contour drawing line in the Q1 model slice image to obtain the Q1 contour line length value, acquire the length value of the contour drawing line in the Q2 model slice image to obtain the Q2 contour line length value, and so on, acquire the length value of the contour drawing line in the Qn model slice image to obtain the Qn contour line length value;

[0188] It should be noted here that:

[0189] In this application, the value of the contour drawing line length involved here is the total length of the contour drawing line of the model slice image;

[0190] Step S372: obtaining a crack length degradation coefficient corresponding to the first crack model slice image by calculating the Q1 contour line length value to the Qn contour line length value;

[0191] The crack length degradation coefficient corresponding to the first crack model slice image is calculated, and the formula is as follows:

[0192] ;

[0193] Wherein, Clx is the crack length degradation coefficient corresponding to the first crack model slice image, Clq i is the length of Qi contour line, Clq i-1 is the length value of the Qi-1 contour line, and n is the number value corresponding to the slice image of the first crack model;

[0194] It should be noted here that:

[0195] In the present application, the Qi contour line length value involved here can be any contour line length value from the Q1 contour line length value to the Qn contour line length value;

[0196] Step S373: respectively acquiring the crack length degradation coefficients corresponding to the second crack model slice image to the cth crack model slice image to obtain a plurality of crack length degradation coefficients;

[0197] Step S374: Calculate the average of the multiple crack length degradation coefficients obtained to obtain the crack length degradation coefficient.

[0198] Step S38: monitoring the number of crack intersections from the first crack model slice image to the cth crack model slice image, and performing a comprehensive analysis on the monitoring results to obtain a crack intersection degradation coefficient;

[0199] The step S38 further includes the following specific steps:

[0200] Step S381: Acquire the number of intersection points of the contour drawing lines in the slice image of the Q1 model to obtain the number of intersection points of the Q1 contour lines, acquire the number of intersection points of the contour drawing lines in the slice image of the Q2 model to obtain the number of intersection points of the Q2 contour lines, and so on, acquire the number of intersection points of the contour drawing lines in the slice image of the Qn model to obtain the number of intersection points of the Qn contour lines;

[0201] Step S382: obtaining the crack intersection degradation coefficient corresponding to the first crack model slice image by calculating the number of Q1 contour line intersections to the number of Qn contour line intersections;

[0202] The crack intersection degradation coefficient corresponding to the first crack model slice image is calculated, and the formula is as follows:

[0203] ;

[0204] Among them, Jdx is the crack intersection degradation coefficient corresponding to the first crack model slice image, Jdq i is the number of intersection points of Qi contour lines, Jdq i-1 is the number of intersections of the Qi-1 contour line, and n is the number value corresponding to the slice image of the first crack model;

[0205] It should be noted here that:

[0206] In the present application, the number of Qi contour line intersections involved here may be any number of contour line intersections from the number of Q1 contour line intersections to the number of Qn contour line intersections;

[0207] Step S383: acquiring the crack intersection degradation coefficients corresponding to the second crack model slice image to the cth crack model slice image to obtain a plurality of crack intersection degradation coefficients;

[0208] Step S384: Calculate the average of the obtained multiple crack intersection degradation coefficients to obtain the crack intersection degradation coefficient.

[0209] Step S39: defining the crack area degradation coefficient, the crack length degradation coefficient and the crack intersection degradation coefficient as crack degradation monitoring data;

[0210] Step S4: obtaining the model gap degradation assessment coefficient by analyzing the crack degradation monitoring data, obtaining the model gap degradation assessment coefficient threshold and performing numerical comparison with the model gap degradation assessment coefficient, performing degradation assessment on the target PFC engineering model according to the numerical comparison result, and issuing a gap degradation warning according to the assessment result;

[0211] The step S4 further includes the following specific steps:

[0212] Step S41: obtaining crack degradation monitoring data, and obtaining crack area degradation coefficient, crack length degradation coefficient and crack intersection degradation coefficient respectively according to the crack degradation monitoring data;

[0213] Step S42: Calculating the crack area degradation coefficient, the crack length degradation coefficient and the crack intersection degradation coefficient to obtain the model crack degradation assessment coefficient;

[0214] The model degradation assessment coefficient is calculated, and the specific formula is as follows:

[0215] ;

[0216] Among them, Mlp is the model degradation assessment coefficient, Sml is the crack area degradation coefficient, Cdl is the crack length degradation coefficient, and Jdl is the crack intersection degradation coefficient;

[0217] Step S43: obtaining a model gap degradation assessment coefficient threshold, performing a numerical comparison between the model gap degradation assessment coefficient and the model gap degradation assessment coefficient threshold, performing a degradation assessment on the target PFC engineering model according to the numerical comparison result, and issuing a gap degradation warning according to the assessment result;

[0218] The step S43 further includes the following specific steps:

[0219] Step S431: respectively obtaining a crack region area degradation coefficient threshold, a crack length degradation coefficient threshold, and a crack intersection degradation coefficient threshold;

[0220] Step S432: Calculating the crack area degradation coefficient threshold, the crack length degradation coefficient threshold, and the crack intersection degradation coefficient threshold to obtain a model crack degradation assessment coefficient threshold;

[0221] It should be noted here that:

[0222] In the present application, the crack region area degradation coefficient threshold, crack length degradation coefficient threshold and crack intersection degradation coefficient threshold involved here are respectively the minimum crack region area degradation coefficient, the minimum crack length degradation coefficient and the minimum crack intersection degradation coefficient corresponding to the PFC engineering model in a normal degradation state;

[0223] The model degradation assessment coefficient threshold is calculated, and the specific formula is as follows:

[0224] ;

[0225] Among them, Mlpy is the model degradation assessment coefficient threshold, Smly is the crack area degradation coefficient threshold, Cdly is the crack length degradation coefficient threshold, and Jdly is the crack intersection degradation coefficient threshold;

[0226] Step S433: when the model gap degradation assessment coefficient is greater than or equal to the model gap degradation assessment coefficient threshold, the target PFC engineering model is assessed to be in an abnormal degradation state, and an abnormal degradation warning is issued;

[0227] Step S434: When the model gap degradation assessment coefficient is less than the model gap degradation assessment coefficient threshold, the assessment target PFC engineering model is in a normal degradation state, and no abnormal degradation warning is issued.

[0228] In this application, if corresponding calculation formulas appear, the above calculation formulas are all dimensionless and take their numerical calculations. The weight coefficients, proportional coefficients and other coefficients in the formulas are set to a result value obtained by quantifying each parameter. The size of the weight coefficient and the proportional coefficient can be determined as long as it does not affect the proportional relationship between the parameter and the result value.

[0229] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for extracting crack degradation image contours for a PFC software model, characterized in that: include: Step S1; Obtain a target PFC engineering model, save the target PFC engineering model at multiple different time nodes into files, obtain multiple PFC model files, create a three-dimensional coordinate system for each PFC model file, and obtain model coordinate system creation data; Step S2: Create data through the model coordinate system to monitor the particle edge of each first characteristic particle, obtain multiple contact coordinate distance differences, and perform distance numerical analysis on each contact coordinate distance difference, and divide the multiple first characteristic particles into crack edge particles and non-crack edge particles according to the analysis results to obtain particle edge analysis data; Step S3: extracting and reconstructing the crack contour of each PFC model file according to the particle edge analysis data and the model coordinate system creation data, obtaining multiple crack contour three-dimensional models, and dividing each crack contour three-dimensional model into a number of crack model slice images, performing crack degradation analysis on each crack model slice image, and obtaining the crack area degradation coefficient, crack length degradation coefficient and crack intersection degradation coefficient according to the analysis results, and obtaining crack degradation monitoring data; The step S3 further includes the following specific steps: Step S31: acquiring model coordinate system creation data, acquiring B1 model coordinate system to Bn model coordinate system respectively according to the model coordinate system creation data, acquiring particle edge analysis data, and acquiring B1 particle edge division data to Bn particle edge division data respectively according to the particle edge analysis data; Step S32: extracting the model crack contour according to the B1 particle edge division data to the Bn particle edge division data, and obtaining the B1 crack contour three-dimensional model to the Bn crack contour three-dimensional model; Step S33: Slicing the B1 crack contour three-dimensional model to obtain the first crack model slice image to the cth crack model slice image corresponding to the B1 crack contour three-dimensional model; Step S34: respectively acquiring the first crack model slice image to the cth crack model slice image corresponding to the B2 crack contour three-dimensional model to the Bn crack contour three-dimensional model; Step S35: naming the first crack model slice image in the B1 crack contour three-dimensional model as the Q1 model slice image, naming the first crack model slice image in the B2 crack contour three-dimensional model as the Q2 model slice image, and so on, naming the first crack model slice image in the Bn crack contour three-dimensional model as the Qn model slice image; Step S36: monitoring the crack region area change from the first crack model slice image to the cth crack model slice image, and performing a comprehensive analysis on the monitoring results to obtain the first crack region area degradation coefficient; The area degradation coefficient of the first crack region is calculated, and the formula is as follows: ； Among them, Scm1 is the area degradation coefficient of the first crack region, Smq i is the area value of the Qi crack region, Smq i-1 is the area value of the Qi-1 crack region, and n is the number value corresponding to the slice image of the first crack model; Step S37: monitoring the crack lengths of the first crack model slice image to the cth crack model slice image, and comprehensively analyzing the monitoring results to obtain a crack length degradation coefficient; The crack length degradation coefficient corresponding to the first crack model slice image is calculated, and the formula is as follows: ； Wherein, Clx is the crack length degradation coefficient corresponding to the first crack model slice image, Clq i is the length of Qi contour line, Clq i-1 is the length value of the Qi-1 contour line, and n is the number value corresponding to the slice image of the first crack model; Step S38: monitoring the number of crack intersections from the first crack model slice image to the cth crack model slice image, and performing a comprehensive analysis on the monitoring results to obtain a crack intersection degradation coefficient; The crack intersection degradation coefficient corresponding to the first crack model slice image is calculated, and the formula is as follows: ； Among them, Jdx is the crack intersection degradation coefficient corresponding to the first crack model slice image, Jdq i is the number of intersection points of Qi contour lines, Jdq i-1 is the number of intersections of the Qi-1 contour line, and n is the number value corresponding to the slice image of the first crack model; Step S39: defining the crack area degradation coefficient, the crack length degradation coefficient and the crack intersection degradation coefficient as crack degradation monitoring data; Step S4: Obtain the model gap degradation assessment coefficient by analyzing the crack degradation monitoring data, obtain the model gap degradation assessment coefficient threshold and perform numerical comparison with the model gap degradation assessment coefficient, and perform degradation assessment on the target PFC engineering model according to the numerical comparison result.

2. A method for extracting crack degradation image contours for a PFC software model according to claim 1, characterized in that: The step S1 further includes the following specific steps: Step S11: Obtain a target PFC project model by using a PFC model corresponding to the target project created by the PFC software; Step S12: saving the target PFC engineering models at multiple different time nodes to obtain multiple PFC model files, and naming the saved multiple PFC model files as B1 model file to Bn model file in the order of the saving time nodes; Step S13: Create a model coordinate system for the B1 model file to obtain the B1 model coordinate system; Step S14: creating model coordinate systems for the B2 model file to the Bn model file respectively, and obtaining the B1 model coordinate system to the Bn model coordinate system; Step S15: define the B1 model coordinate system to the Bn model coordinate system as model coordinate system creation data.

3. A method for extracting crack degradation image contours for a PFC software model according to claim 2, characterized in that: The step S13 further includes the following specific steps: Step S131: Open the B1 model file in the PFC software to obtain the B1 engineering model. In the B1 engineering model, use a plurality of first characteristic particles to fill the crack area in the B1 engineering model, and use a plurality of second characteristic particles to fill the non-crack area in the B1 engineering model to obtain the B1 engineering filling model; Step S132: randomly select a model vertex in the B1 engineering filling model as a feature coordinate point, randomly draw a straight line through the feature coordinate point to obtain a first model feature line, and mark the plane where the first model feature line is located as the first feature plane, and in the first feature plane, draw a straight line perpendicular to the first model feature line through the feature coordinate point to obtain a second model feature line, and draw a straight line perpendicular to the first feature plane through the feature coordinate point to obtain a third model feature line; Step S133: In the B1 engineering filling model, the characteristic coordinate point is marked as the coordinate origin, the first model characteristic line is marked as the coordinate x-axis, the second model characteristic line is marked as the coordinate y-axis, the third model characteristic line is marked as the coordinate z-axis, and the three-dimensional rectangular coordinate system composed of the coordinate origin, the coordinate x-axis, the coordinate y-axis and the coordinate z-axis is named the B1 model coordinate system. Step S134: in the B1 model coordinate system, the geometric center corresponding to each characteristic particle is obtained respectively, and the geometric center corresponding to each characteristic particle is marked as a coordinate point in the B1 model coordinate system.

4. The method for extracting crack degradation image contours for a PFC software model according to claim 1, characterized in that: The step S2 further includes the following specific steps: Step S21: Acquire model coordinate system creation data, and acquire B1 model coordinate system to Bn model coordinate system respectively according to the model coordinate system creation data; Step S22: performing particle edge analysis on the first characteristic particle in the B1 model coordinate system, and obtaining B1 particle edge division data according to the analysis result; Step S23: respectively acquiring the particle edge division data corresponding to the B2 model coordinate system to the Bn model coordinate system, and obtaining the B2 particle edge division data to the Bn particle edge division data; Step S24: defining B1 particle edge division data to Bn particle edge division data as particle edge analysis data; The step S22 further includes the following specific steps: Step S221: selecting a sample characteristic particle from a plurality of first characteristic particles in the B1 model coordinate system; Step S222: acquiring the coordinate points corresponding to the characteristic particles of the sample in the B1 model coordinate system to obtain the coordinates of the sample particles; Step S223: in the B1 model coordinate system, characteristic particles in contact with the sample characteristic particles are acquired to obtain a plurality of characteristic contact particles, and the acquired plurality of characteristic contact particles are named as the first characteristic contact particle to the ath characteristic contact particle respectively; Step S224: respectively acquiring the coordinates corresponding to the first characteristic contact particle to the ath characteristic contact particle in the B1 model coordinate system to obtain the first characteristic contact coordinates to the ath characteristic contact coordinates; Step S225: calculating the contact coordinate distance difference corresponding to the sample characteristic particle from the first characteristic contact coordinate to the ath characteristic contact coordinate and the sample particle coordinate; The contact coordinate distance difference corresponding to the characteristic particles of the sample is calculated. The specific formula is as follows: ； Where Jjc is the contact coordinate distance difference corresponding to the characteristic particles of the sample, (x t ,y t ,z t ) is the sample particle coordinate, (x i ,y i ,z i ) is the i-th characteristic contact coordinate, a is the quantity value corresponding to the characteristic contact particle; Step S226: acquiring the contact coordinate distance difference corresponding to each first characteristic particle respectively to obtain a plurality of contact coordinate distance differences; Step S227: obtaining the reference coordinate distance difference, calculating the difference between each basic coordinate distance difference and the reference coordinate distance difference, and taking the absolute value of the obtained difference to obtain the distance deviation of multiple coordinate points; Step S228: obtaining a coordinate point distance deviation threshold, numerically comparing each coordinate point distance deviation with the coordinate point distance deviation threshold, and dividing the first characteristic particles into crack edge particles and non-crack edge particles according to the numerical comparison result, to obtain B1 particle edge division data; The details are as follows: If the coordinate point distance deviation is greater than or equal to the coordinate point distance deviation threshold, the corresponding first characteristic particle is classified as a crack edge particle; If the coordinate point distance deviation is less than the coordinate point distance deviation threshold, the corresponding first characteristic particle is classified as a non-crack edge particle.

5. The method for extracting crack degradation image contours for a PFC software model according to claim 1, characterized in that: The step S33 further includes the following specific steps: Step S331: Mark a number of feature cutting points with equal intervals on the coordinate z axis in the B1 model coordinate system to obtain the first feature cutting point to the cth feature cutting point; Step S332: Draw a plane perpendicular to the coordinate y-axis through the first feature cutting point to the c-th feature cutting point to obtain the first feature cutting plane to the c-th feature cutting plane, and acquire images of the model slices of the B1 crack contour three-dimensional model from the first feature cutting plane to the c-th feature cutting plane to obtain the first crack model slice image to the c-th crack model slice image.

6. A method for extracting crack degradation image contours for a PFC software model according to claim 5, characterized in that: The step S32 further includes the following specific steps: Step S321: acquiring crack edge particles of the B1 engineering filling model according to the B1 particle edge division data, respectively acquiring the three-dimensional coordinates of each crack edge particle in the B1 model coordinate system, and obtaining a plurality of crack edge three-dimensional coordinates; Step S322: constructing the acquired three-dimensional coordinates of the multiple crack edges into a point cloud data set, and using a curve fitting algorithm to extract the contour of the point cloud data set to obtain the B1 crack contour; Step S323: Line drawing is performed on the B1 crack contour to obtain a plurality of contour drawing lines, and the plurality of contour drawing lines are connected by an image tool to obtain a crack contour three-dimensional model corresponding to the B1 engineering filling model, and the model is named B1 crack contour three-dimensional model; Step S324: respectively acquiring the three-dimensional models of the crack contours corresponding to the B2 engineering filling model to the Bn engineering filling model, and obtaining the B2 crack contour three-dimensional model to the Bn crack contour three-dimensional model.

7. The method for extracting crack degradation image contours for a PFC software model according to claim 5, characterized in that: The step S36 further includes the following specific steps: Step S361: acquiring the area value of the first characteristic particle coverage area in the Q1 model slice image to obtain the area value of the Q1 crack area, acquiring the area value of the first characteristic particle coverage area in the Q2 model slice image to obtain the area value of the Q2 crack area, and so on, acquiring the area value of the first characteristic particle coverage area in the Qn model slice image to obtain the area value of the Qn crack area; Step S362: Calculate the area value of the crack region Q1 to the area value of the crack region Qn to obtain the first crack region area degradation coefficient; Step S363: monitoring the crack region area change of the second crack model slice image to the c-th crack model slice image respectively, and obtaining the second crack region area degradation coefficient to the c-th crack region area degradation coefficient; Step S364: Calculate the average of the first crack region area degradation coefficient to the cth crack region area degradation coefficient to obtain the crack region area degradation coefficient.

8. The method for extracting crack degradation image contours for a PFC software model according to claim 5, characterized in that: The step S37 further includes the following specific steps: Step S371: Acquire the length value of the contour drawing line in the Q1 model slice image to obtain the Q1 contour line length value, and similarly, acquire the length value of the contour drawing line in the Qn model slice image to obtain the Qn contour line length value; Step S372: obtaining a crack length degradation coefficient corresponding to the first crack model slice image by calculating the Q1 contour line length value to the Qn contour line length value; Step S373: respectively acquiring the crack length degradation coefficients corresponding to the second crack model slice image to the cth crack model slice image to obtain a plurality of crack length degradation coefficients; Step S374: Calculate the average of the multiple crack length degradation coefficients obtained to obtain the crack length degradation coefficient.

9. The method for extracting crack degradation image contours for a PFC software model according to claim 5, characterized in that: The step S38 further includes the following specific steps: Step S381: Acquire the number of intersection points of the contour drawing lines in the slice image of the Q1 model to obtain the number of intersection points of the Q1 contour lines, acquire the number of intersection points of the contour drawing lines in the slice image of the Q2 model to obtain the number of intersection points of the Q2 contour lines, and so on, acquire the number of intersection points of the contour drawing lines in the slice image of the Qn model to obtain the number of intersection points of the Qn contour lines; Step S382: obtaining the crack intersection degradation coefficient corresponding to the first crack model slice image by calculating the number of Q1 contour line intersections to the number of Qn contour line intersections; Step S383: acquiring the crack intersection degradation coefficients corresponding to the second crack model slice image to the cth crack model slice image to obtain a plurality of crack intersection degradation coefficients; Step S384: Calculate the average of the obtained multiple crack intersection degradation coefficients to obtain the crack intersection degradation coefficient.

10. The method for extracting crack degradation image contours for a PFC software model according to claim 1, characterized in that: The step S4 further includes the following specific steps: Step S41: obtaining crack degradation monitoring data, and obtaining crack area degradation coefficient, crack length degradation coefficient and crack intersection degradation coefficient respectively according to the crack degradation monitoring data; Step S42: Calculating the crack area degradation coefficient, the crack length degradation coefficient and the crack intersection degradation coefficient to obtain the model crack degradation assessment coefficient; Step S43: obtaining a model gap degradation assessment coefficient threshold, performing a numerical comparison between the model gap degradation assessment coefficient and the model gap degradation assessment coefficient threshold, and performing a degradation assessment on the target PFC engineering model according to the numerical comparison result; The step S43 further includes the following specific steps: Step S431: respectively obtaining a crack region area degradation coefficient threshold, a crack length degradation coefficient threshold, and a crack intersection degradation coefficient threshold; Step S432: Calculating the crack area degradation coefficient threshold, the crack length degradation coefficient threshold, and the crack intersection degradation coefficient threshold to obtain a model crack degradation assessment coefficient threshold; Step S433: when the model gap degradation assessment coefficient is greater than or equal to the model gap degradation assessment coefficient threshold, the target PFC engineering model is assessed to be in an abnormal degradation state; Step S434: When the model gap degradation assessment coefficient is less than the model gap degradation assessment coefficient threshold, the target PFC engineering model is assessed to be in a normal degradation state.

Images