CN110415167B - Rough surface crack generation method and test system based on digital image technology - Google Patents
Rough surface crack generation method and test system based on digital image technology Download PDFInfo
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Abstract
The invention provides a rough surface crack generation method and a test system based on a digital image technology, which relate to the technical field of rock mechanics tests and comprise the following steps: A. loading a rock test piece, forming a through fracture in the test piece, and removing chips on the surface of the test piece; B. scanning the rough crack surface by a scanner to obtain a digital image of the rough crack surface; C. processing the digital image, including noise removal processing and threshold segmentation processing; D. carrying out normalization processing on the RGB value of the digital image to obtain a normalization matrix, establishing a space coordinate system and obtaining the reduction proportion of the image digital matrix; E. calculating a digital reduction matrix; F. the simulation of rough surface cracks is completed, and complete space cracks are restored; the test system comprises a shell, a stand column, a telescopic oil cylinder array, a control system and a hydraulic loop. The invention provides a method for researching the seepage physical and mechanical law of rough cracks of rocks, and accurately describes the rough structure of the cracks of the rocks.
Description
Technical Field
The invention relates to the technical field of rock mechanical tests, in particular to a rough surface crack generation method based on a digital image technology and a test system for simulating rough surface cracks.
Background
The natural fracture structure and the seepage behavior of the rock mass are extremely complex, the seepage mechanism and the quantitative description of the rock mass fracture are difficult problems which are highly concerned by the rock-soil, mining industry, geology, petroleum and natural gas engineering, joints, fractures and the like in the rock mass are main channels for groundwater seepage, and the influence of the surface roughness of the rock mass fracture on the groundwater seepage is large. The fracture in the natural rock mass is influenced by complex geological action for a long time, the roughness characteristics of the surface of the fracture are different, and the roughness of the surface of the rock mass is difficult to visually represent in numerical simulation, so the fracture surface is simplified into two parallel plates, the fracture surface is assumed to be smooth, or probability density functions in statistics are applied to assume a probability distribution to describe and process the heterogeneity of the fracture surface of the rock mass, the influence of surface roughness on seepage is researched to a certain extent, but for a specific rock mass surface fracture, the actual surface fluctuation structure of the fracture cannot be reflected at present. The different strengths of the components of the rock enable the roughness of the rock fracture surface to be greatly different, and the rock stress-seepage coupling characteristics can be more objectively reflected only by accurately describing the fluctuation roughness structure of the rock fracture surface.
Digital image processing technology has been widely used in quantitative analysis of microscopic structures of rock, soil and concrete as a means for accurately measuring spatial structures on microscopic scales of materials and for digitally describing the spatial structures. The digital image technology classifies and extracts the graphic information obtained by the digital equipment, converts the graphic information into a numerical value between 0 and 1 through normalization processing, and restores the physical parameters according to the corresponding actually measured information of the physical parameters. The main application of the technology at the present stage comprises non-contact measurement of rock fracture width, digital representation of rock mass heterogeneity and the like.
The method can not avoid the interference of uncertain factors in the test on the reconstruction of the crack, can not respectively carry out different tests on two test pieces with the same crack condition in the fluid-solid coupling test, can not accurately obtain the hydraulic opening of a joint plane, and lacks necessary research methods and test means for researching the fluid-solid coupling problem of the fractured rock mass of the rock from a microscopic scale; further improvements to existing testing methods and systems are needed.
Disclosure of Invention
In order to provide a method for researching the seepage physical mechanical law of rough cracks of rocks, accurately describe the rough structure of the cracks of the rocks and provide convenience for researching the fluid-solid coupling problem of fractured rocks of the rocks in a microscopic scale, the invention provides a rough surface crack generation method and a test system based on a digital image technology, and the specific technical scheme is as follows.
A rough surface crack generation method based on a digital image technology comprises the following steps:
a, manufacturing a rock test piece, loading the rock test piece on a rock mechanical testing machine, forming a through crack in the test piece, and then removing chips on the surface of the rock test piece;
b, scanning the rough crack surface through a scanner to obtain a digital image of the rough crack surface;
c, processing the digital image, including noise removal processing and threshold segmentation processing;
d, normalizing the processed digital image RGB value to obtain a normalized matrix of the digital image surface, establishing a space coordinate system, measuring the fluctuation height of the origin of the coordinate system, and obtaining the reduction ratio of the image digital matrix;
e, calculating to obtain a digital reduction matrix, wherein the reduction proportion is multiplied by the normalization matrix;
and F, completing simulation of the rough surface crack by utilizing a digital reduction matrix and a rough surface crack generation test system based on a digital image technology, and reducing the complete space crack.
Preferably, the rock test piece comprises a cuboid test piece, a cube test piece and a cylindrical test piece, and the rock mechanical testing machine comprises a single-axis loading testing machine and a three-axis loading testing machine; debris on the surface of the rock specimen was cleaned using a dry brush. The scanner is a laser scanner or a CT scanner and the digital image is a bitmap or a vector map.
Preferably, the establishment of the spatial coordinate system takes a determined point on the fracture surface as the origin.
Further preferably, the normalization processing comprises normalization processing of the brightness value I, and distinguishing whether the rock mass surface crack is concave or convex; and when the lowest point of the concave surface of the rock is taken as a horizontal plane, the I values of the digital images are all larger than 0.
It is further preferred that the value of I at the origin is hm(x) Selecting the plane where the lowest point of the downward concave of the rock mass surface crack is as a reference surface, and actually measuring the elevation value h between the original point and the reference surfaces(x) And obtaining a reduction scale factor.
Still preferably, rough surface crack generation test system based on digital image technique, including casing, stand, flexible hydro-cylinder array, control system and hydraulic circuit, the casing includes upper housing and lower casing, and the stand is connected upper housing and lower casing, and flexible hydro-cylinder array includes upper portion flexible hydro-cylinder group and lower part flexible hydro-cylinder group, and upper portion flexible hydro-cylinder group and lower part flexible hydro-cylinder group all are provided with a plurality of closely arranged's flexible hydro-cylinder, and control system controls hydraulic circuit work, and the flexible hydro-cylinder of hydraulic circuit control is flexible.
Still further preferably, a plurality of vertical columns are arranged at the edges of the upper shell and the lower shell, the vertical columns are of telescopic structures, and the vertical columns can simultaneously stretch and adjust the distance between the upper shell and the lower shell.
Still further preferably, the edges of the upper telescopic cylinder group and the lower telescopic cylinder group are provided with baffle plates, and the telescopic cylinders of the upper telescopic cylinder group and the lower telescopic cylinder group are oppositely arranged and matched with each other; the section of the telescopic oil cylinder is rectangular.
It is further preferred that the simulation of the asperity crack includes a simulation of an upper asperity crack and a simulation of a lower asperity crack;
specifically, in the simulation of the lower rough surface crack, a digital reduction matrix of the lower rough surface crack is obtained firstly and recorded as [ A ]]To [ A ]]Is subjected to normalization processing to obtain
Determination by Matlab
Determining the coordinate positions of a minimum point and a maximum point, and determining the distance h between the reference surface of the lower crack and the bottom surface of the rock test piece1The heights of the minimum point and the maximum point relative to the reference plane are recorded as ξ1And ξ2And obtaining a state function of any point on the surface of the lower rough surface crack in a coordinate system:
in the simulation of the upper rough surface crack, a digital reduction matrix of the lower rough surface crack is firstly obtained and recorded as [ B ]]To [ B ]]Is subjected to normalization processing to obtain
Determination by Matlab
Determining the coordinate positions of a minimum point and a maximum point, and determining the distance h between the reference surface of the upper crack and the bottom surface of the rock test piece2Determining the height of the minimum and maximum points relative to the reference plane simultaneouslyDegree is respectively recorded as η1And η2And obtaining a state function of any point on the crack surface of the upper rough surface in a coordinate system:
combining the lower rough surface fracture and the upper rough surface fracture, selecting an origin on the bottom surface of the rock test piece, and establishing a new space coordinate system, wherein the fracture opening spatial distribution function omega (x) is as follows:
inputting the digital reduction matrix through a computer of a control system, and generating a complete space fracture by a test system based on the rough surface fracture of the digital image technology to obtain a fracture space distribution model;
the fracture space distribution model is applied to a rough surface fractured rock mass seepage simulation test.
The utility model provides a test system for rough surface crack generates method, includes casing, stand, flexible hydro-cylinder array, control system and hydraulic circuit, the casing includes upper housing and lower casing, the stand is connected upper housing and lower casing, flexible hydro-cylinder array includes the flexible hydro-cylinder group in upper portion and the flexible hydro-cylinder group in lower part, and the flexible hydro-cylinder group in upper portion and the flexible hydro-cylinder group in lower part all are provided with a plurality of closely arranged's flexible hydro-cylinder, control system control hydraulic circuit work, the flexible hydro-cylinder of hydraulic circuit control is flexible.
The beneficial effects of the invention include:
(1) the method accurately reproduces the appearance characteristics of rough surface cracks damaged by stretching, twisting or shearing of a rock test piece by processing digital images and truly simulates the fluctuation change characteristics of rough surface cracks of rock joints.
(2) The method comprises the steps of obtaining a digital image, and carrying out data processing on the digital image to obtain a digital reduction matrix; simulating and reducing a rough crack surface by utilizing the matrix in a rough surface crack generation test system based on a digital image technology; the system has the advantages of high accuracy, low cost, good repeatability, simple operation and the like; and the system can repeatedly reduce a plurality of different rough crack surfaces, thereby providing a more convenient test method for the indoor rock mechanical test.
(3) The method is used for processing the fracture surface image, well reducing the distribution of rock body fractures, reducing a fracture space distribution model obtained by reducing a complete space fracture by using a rough surface fracture generation test system based on a digital image technology, is applied to a seepage test, can accurately obtain the hydraulic opening of a joint surface, effectively simulates the flowing process of fracture flow, avoids the defects of large discreteness and poor repeatability of rough rock fractures, and provides reference for researching the fracture-rock mass fluid-solid coupling problem of rock from a microscopic scale. In addition, the method and the test system can complete the test of the physical and mechanical properties of the structural surface under different conditions, and have wide application prospect in seepage tests.
Drawings
FIG. 1 is a flow chart of a rough surface crack generation method based on digital image technology;
FIG. 2 is a schematic of a digital image and a normalized image of a rough fracture surface;
FIG. 3 is a gray scale distribution rule chart of collected digital images of the surface of a rough crack;
FIG. 4 is a schematic cross-sectional view of a rough fracture surface structure;
FIG. 5 is a schematic diagram of a spatial coordinate system established for constructing spatial fracture distribution features;
FIG. 6 is a schematic view of the simulation of the upper rough surface crack and the simulation of the lower rough surface crack;
FIG. 7 is a diagram of a fracture simulation three-dimensional model;
FIG. 8 is a schematic diagram of a rough surface crack generation test system based on digital image technology;
FIG. 9 is a schematic diagram of the external structure of the test system;
FIG. 10 is a schematic view of the upper and lower telescopic cylinder groups;
FIG. 11 is a partial enlarged view of the telescopic cylinder array;
FIG. 12 is a cross-sectional exploded view of a simulated rough fracture surface;
in the figure: 1-a shell; 11-an upper shell; 12-a lower housing; 2-upright post; 3-telescopic oil cylinder array; 4-a control system; 5-hydraulic circuit.
Detailed Description
Referring to fig. 1 to 12, the rough surface crack generation method and the test system according to the present invention based on the digital image technology are described as follows.
The simulation of the rough fracture surface of the rock mass mostly adopts resin materials to copy rock surface characteristics, and then reconstructs the fracture surface by using similar materials, so that the method can not avoid the interference of uncertain factors on fracture reconstruction in multiple copying and manufacturing processes in a test, two test pieces with the same fracture condition can not be respectively subjected to different tests in a fluid-solid coupling test, the hydraulic opening of a joint surface can not be accurately obtained, and the problem of fluid-solid coupling of the fractured rock mass in the study of the microscopic scale lacks of necessary research methods and test means. The method comprises the steps of obtaining a digital image of a fracture surface, establishing a digital model, obtaining a data value of a corresponding point of the fracture surface by utilizing an actual measurement result of a certain point on the rock fracture surface, obtaining a scale factor of the height difference between the image and the actual fracture, reducing surface fluctuation information, obtaining a fracture space distribution model through a digital reduction matrix, carrying out a fluid-solid coupling simulation test on the fracture space distribution model, and obtaining a fracture flow velocity which is obviously smaller than that of a simulation of a similar material through a result, wherein the fracture numerical simulation can accurately obtain the hydraulic opening of a joint surface, thereby effectively simulating the fracture flow process.
A rough surface crack generation method based on digital image technology, as shown in fig. 1, includes the steps of:
and A.
And manufacturing a rock test piece, loading the rock test piece on a rock mechanical testing machine, forming a through crack in the test piece, and then removing the surface chips of the rock test piece.
The rock test piece includes the test pieces of multiple shapes and sizes such as cuboid test piece, square test piece and cylindrical test piece, and the test piece is formed by on-the-spot rock sample preparation, and the rock mechanics testing machine includes testing machines such as unipolar loading testing machine and triaxial loading testing machine, and testing machine loading test piece obtains running through the crack. Debris on the surface of the rock specimen is cleaned using a dry brush to eliminate interference of the debris with the imaging of the fracture surface.
And B, step B.
And scanning the surface of the rough crack by a scanner to obtain a digital image of the surface of the rough crack, wherein the image is in a jpg format or a bmp format and other processable image formats. Wherein the scanner is a laser scanner, a rock scanner or a CT scanner, and the digital image is a bitmap or a vector map.
And C, performing step C.
And processing the digital image, including denoising processing and threshold segmentation processing, so as to ensure the quality of the digital image of the crack surface. Wherein, the obtained digital image has obvious peak value, which can be used as the determined segmentation threshold value. The image is degraded due to interference and influence of various noises in the generation and transmission processes, and the noise types include electrical noise, mechanical noise, channel noise and other noises, which have adverse effect on the processing (such as segmentation, compression, image understanding and the like) of the subsequent image; common methods for removing image noise include folded mean filter denoising, folded adaptive wiener filter denoising, folded median filter denoising, morphological noise filter denoising, wavelet denoising, etc.
And D, step D.
And normalizing the RGB value of the processed digital image to obtain a normalized matrix of the surface of the digital image, establishing a space coordinate system, measuring the fluctuation height of the origin of the coordinate system, and obtaining the reduction ratio of the digital matrix of the image.
The image RGB values, i.e. luminance, and are represented using integers. Typically, RGB has 256 levels of brightness, each represented numerically from 0 to 255. The gray scale value refers to the color depth of the point in the black-and-white image, and generally ranges from 0 to 255, white is 255, and black is 0. Therefore, the acquired digital image can be a black-and-white image or a color image, and the image quality requirement of the processing condition is met.
Wherein, the establishment of the space coordinate system selects a determined point on the crack surface as an origin. The normalization processing comprises the step of normalizing the brightness value I to distinguish whether the rock surface crack is concave or convex; and when the lowest point of the concave surface of the rock is taken as a horizontal plane, the I values of the digital images are all larger than 0. I value of origin is hm(x) Selecting the plane where the lowest point of the downward concave of the rock mass surface crack is as a reference surface, and actually measuring the elevation value h between the original point and the reference surfaces(x) And obtaining a reduction scale factor.
Taking a specific test as an example, the distribution frequency distribution of the digital image gray scale image of the rough fracture surface is shown in fig. 3, and the brightness value I of the image is normalized to distinguish whether the rock surface fracture is concave or convex. Fig. 2 shows normalized distribution diagrams of I values of three sets of fracture surface images, the lowest point of the depression of the rock surface is taken as a horizontal plane, and the horizontal plane is taken as a reference plane and is shown in fig. 4, so that the I values in the graphs are all larger than 0, the I value distribution is between 0.1 and 0.9, the given fracture surface and the normalized digital image in fig. 2 are compared, the given fracture surface image of the rock and the generated I value image are completely equivalent, and the I value segmentation method based on the threshold value and the image processing technology is good in representation of the undulation of the fracture surface of the rock.
Wherein, after the acquired I value is normalized, an image data matrix fig (x) is obtained, and in the test, a calculation model of 300mm × 150mm × 150mm is established. Then obtaining the I value h of a certain point in the imagem(x) Taking the horizontal plane of the concave deepest point in the model as a reference, and obtaining an elevation actual value h corresponding to a selected point in the image by a measuring methods(x)。
And E, step E.
And calculating to obtain a digital reduction matrix, wherein the reduction proportion is multiplied by the normalization matrix.
After calculating the reduction scale factor by taking the above test as an example, the fracture surface image can be reduced according to the obtained I-value function fig (x) to obtain an actual function h (x) of the fracture surface, and the rough fracture surface is shown in fig. 4.
And F.
And (3) completing simulation of the rough surface crack by utilizing a digital reduction matrix and a rough surface crack generation test system based on a digital image technology, and reducing the complete space crack.
Wherein the simulation of the rough-surface crack includes simulation of an upper rough-surface crack and simulation of a lower rough-surface crack.
In the simulation of the lower rough surface crack, a digital reduction matrix of the lower rough surface crack is firstly obtained and recorded as [ A ]]To [ A ]]Is subjected to normalization processing to obtain
Determination by Matlab
Determining the coordinate positions of a minimum point and a maximum point, and determining the distance h between the reference surface of the lower crack and the bottom surface of the rock test piece1The heights of the minimum point and the maximum point relative to the reference plane are recorded as ξ1And ξ2And obtaining a state function of any point on the surface of the lower rough surface crack in a coordinate system:
in the simulation of the upper rough surface crack, a digital reduction matrix of the lower rough surface crack is firstly obtained and recorded as [ B ]]To [ B ]]Is subjected to normalization processing to obtain
Determination by Matlab
Determining the coordinate positions of a minimum point and a maximum point, and determining the distance h between the reference surface of the upper crack and the bottom surface of the rock test piece2The heights of the minimum point and the maximum point relative to the reference plane are recorded as η1And η2And obtaining a state function of any point on the crack surface of the upper rough surface in a coordinate system:
combining the lower rough surface fracture and the upper rough surface fracture, selecting an origin on the bottom surface of the rock test piece, and establishing a new space coordinate system, wherein as shown in fig. 5 to 7, a fracture opening degree space distribution function omega (x) is as follows:
inputting the digital reduction matrix through a computer of a control system, and generating a complete space fracture by a test system based on the rough surface fracture of the digital image technology to obtain a fracture space distribution model; the fracture space distribution model can be applied to rough surface fractured rock mass seepage simulation tests.
According to the rough surface crack generation method based on the digital image technology, the rough surface crack appearance characteristics of the rock test piece in stretching, torsion or shearing damage are accurately reproduced through processing the digital image, and the fluctuation change characteristics of the rough crack surface of the rock joint are really simulated; acquiring a digital image, and performing data processing on the digital image to obtain a digital reduction matrix; simulating and reducing a rough crack surface by utilizing the matrix in a rough surface crack generation test system based on a digital image technology; the system has the advantages of high accuracy, low cost, good repeatability, simple operation and the like; and the system can repeatedly reduce a plurality of different rough crack surfaces, thereby providing a more convenient test method for the indoor rock mechanical test.
As shown in fig. 8 to 12, the rough surface crack generation test system based on the digital image technology includes a housing 1, a column 2, a telescopic cylinder array 3, a control system 4, and a hydraulic circuit 5, where the housing 1 includes an upper housing 11 and a lower housing 12, the column 2 connects the upper housing 11 and the lower housing 12, the telescopic cylinder array 3 includes an upper telescopic cylinder group and a lower telescopic cylinder group, both the upper telescopic cylinder group and the lower telescopic cylinder group are provided with a plurality of telescopic cylinders closely arranged, the control system 4 controls the hydraulic circuit 5 to operate, and the hydraulic circuit 5 controls the telescopic cylinders to extend and retract. The shell 1 has a stable structure, and the structure formed by combining the upper shell and the lower shell covers the whole test device, so that the system is prevented from being interfered by the external environment; the upright posts ensure connection and combination of the upper shell and the lower shell, the telescopic cylinder array can simulate any combination of rough surface cracks within the area and volume range, and the control system and the control loop are used for accurately controlling the telescopic oil cylinder.
Wherein the edge of going up casing 11 and casing 12 down is provided with a plurality of stands 2, and the marginal symmetrical arrangement of casing 11 and casing 12 down can be followed to a plurality of stands 2, and its stand 2 can be for extending structure, and the distance between casing and the casing down is gone up in the telescopic adjustment simultaneously to stand 2 to make things convenient for the operation and the observation of crack simulation. The edge of the upper telescopic oil cylinder group and the lower telescopic oil cylinder group is provided with a baffle plate for limiting the upper telescopic oil cylinder group and the lower telescopic oil cylinder group, and the telescopic oil cylinders of the upper telescopic oil cylinder group and the lower telescopic oil cylinder group are oppositely arranged and matched with each other, as shown in fig. 10 and 12, the telescopic oil cylinders of the upper telescopic oil cylinder group and the lower telescopic oil cylinder group can be ensured to be orderly corresponding one by one. The cross section of the telescopic oil cylinders is rectangular, water drainage treatment is needed between the connected telescopic oil cylinders, and a rough surface fracture rock mass seepage simulation test is conveniently carried out.
The method processes the fracture surface image, well restores the distribution of rock body fractures, utilizes a rough surface fracture generation test system based on a digital image technology to restore a complete spatial fracture to obtain a fracture spatial distribution model, can accurately obtain the hydraulic opening of a joint plane if applied to a seepage test, effectively simulates the flowing process of fracture flow, avoids the defects of large discreteness and poor repeatability of rough rock fractures, and provides reference for researching the fracture rock body fluid-solid coupling problem of the rock from a microscopic scale. In addition, the method and the test system can complete the test of the physical and mechanical properties of the structural surface under different conditions, and have wide application prospect in seepage tests.
It is to be understood that the above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and those skilled in the art may make modifications, alterations, additions or substitutions within the spirit and scope of the present invention.
Claims (10)
1. A rough surface crack generation method based on a digital image technology is characterized by comprising the following steps:
a, manufacturing a rock test piece, loading the rock test piece on a rock mechanical testing machine, forming a through crack in the test piece, and then removing chips on the surface of the rock test piece;
b, scanning the rough crack surface through a scanner to obtain a digital image of the rough crack surface;
c, processing the digital image, including noise removal processing and threshold segmentation processing;
d, normalizing the processed digital image RGB value to obtain a normalized matrix of the digital image surface, establishing a space coordinate system, measuring the fluctuation height of the origin of the coordinate system, and obtaining the reduction ratio of the image digital matrix;
e, calculating to obtain a digital reduction matrix, wherein the reduction proportion is multiplied by the normalization matrix;
f, utilizing a digital reduction matrix and a rough surface crack generation test system based on a digital image technology to complete simulation of the rough surface crack and reduce a complete space crack;
the simulation of the rough surface crack comprises the simulation of an upper rough surface crack and the simulation of a lower rough surface crack;
specifically, in the simulation of the lower rough surface crack, a digital reduction matrix of the lower rough surface crack is obtained firstly and recorded as [ A ]]To [ A ]]Is subjected to normalization processing to obtain
Determination by Matlab
Determining the coordinate positions of a minimum point and a maximum point, and determining the distance h between the reference surface of the lower crack and the bottom surface of the rock test piece1The heights of the minimum point and the maximum point relative to the reference plane are recorded as ξ1And ξ2And obtaining a state function of any point on the surface of the lower rough surface crack in a coordinate system:
in the simulation of the upper rough surface crack, a digital reduction matrix of the lower rough surface crack is firstly obtained and recorded as [ B ]]To [ B ]]Is subjected to normalization processing to obtain
Determination by Matlab
Determining the coordinate positions of a minimum point and a maximum point, and determining the distance h between the reference surface of the upper crack and the bottom surface of the rock test piece2The heights of the minimum point and the maximum point relative to the reference plane are recorded as η1And η2And obtaining a state function of any point on the crack surface of the upper rough surface in a coordinate system:
combining the lower rough surface fracture and the upper rough surface fracture, selecting an origin on the bottom surface of the rock test piece, and establishing a new space coordinate system, wherein the fracture opening spatial distribution function omega (x) is as follows:
and inputting the digital reduction matrix through a computer of the control system, and generating a complete space fracture by the test system based on the rough surface fracture of the digital image technology to obtain a fracture space distribution model.
2. The method for generating rough surface cracks based on the digital image technology is characterized in that the rock test pieces comprise cuboid test pieces, cube test pieces and cylindrical test pieces, and the rock mechanical testing machine comprises a uniaxial loading testing machine and a triaxial loading testing machine; cleaning the debris on the surface of the rock test piece by using a dry brush; the scanner is a laser scanner or a CT scanner, and the digital image is a bitmap or a vector image.
3. The method as claimed in claim 1, wherein the creation of the spatial coordinate system selects a determined point on the fracture surface as the origin.
4. The method for generating rough surface fractures based on digital image technology as claimed in claim 3, wherein the normalization process comprises normalizing the brightness value I to distinguish whether the fractures on the rock surface are concave or convex; and when the lowest point of the concave surface of the rock is taken as a horizontal plane, the I values of the digital images are all larger than 0.
5. The method as claimed in claim 4, wherein the origin I has a value hm(x) Selecting the plane where the lowest point of the downward concave of the rock mass surface crack is as a reference surface, and actually measuring the elevation value h between the original point and the reference surfaces(x) And obtaining a reduction scale factor.
6. The rough surface crack generation method based on the digital image technology as claimed in any one of claims 1 to 5, wherein the rough surface crack generation test system based on the digital image technology comprises a housing, a vertical column, a telescopic cylinder array, a control system and a hydraulic circuit, the housing comprises an upper housing and a lower housing, the vertical column is connected with the upper housing and the lower housing, the telescopic cylinder array comprises an upper telescopic cylinder group and a lower telescopic cylinder group, the upper telescopic cylinder group and the lower telescopic cylinder group are respectively provided with a plurality of closely-arranged telescopic cylinders, the control system controls the operation of the hydraulic circuit, and the hydraulic circuit controls the telescopic cylinders to extend and retract.
7. The method as claimed in claim 6, wherein a plurality of posts are provided at the edges of the upper and lower casings, the posts are of a telescopic structure, and the posts simultaneously extend and contract to adjust the distance between the upper and lower casings.
8. The rough surface crack generation method based on the digital image technology as claimed in claim 7, wherein the edges of the upper and lower telescopic cylinder groups are provided with baffle plates, and the telescopic cylinders of the upper and lower telescopic cylinder groups are oppositely arranged and matched with each other; the section of the telescopic oil cylinder is rectangular.
9. The rough surface fracture generation method based on the digital image technology as claimed in claim 7 or 8, wherein the fracture spatial distribution model is applied to a rough surface fractured rock mass seepage simulation test.
10. A test system for a rough surface crack generation method is used for realizing the rough surface crack generation method based on the digital image technology, which is characterized by comprising a shell, a stand column, a telescopic oil cylinder array, a control system and a hydraulic circuit, wherein the shell comprises an upper shell and a lower shell, the stand column is connected with the upper shell and the lower shell, the telescopic oil cylinder array comprises an upper telescopic oil cylinder group and a lower telescopic oil cylinder group, the upper telescopic oil cylinder group and the lower telescopic oil cylinder group are respectively provided with a plurality of closely-arranged telescopic oil cylinders, the control system controls the hydraulic circuit to work, and the hydraulic circuit controls the telescopic oil cylinders to stretch out and retract.
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