Simulation method and system for evaluating roughness evolution of rock mass discontinuities

Abstract

The application provides a simulation method and system for evaluating roughness evolution of rock mass structure surface, and the method comprises the following steps: performing photoelastic test based on a replication model to obtain a first photoelastic fringe image; performing denoising pretreatment on the first photoelastic fringe image to obtain a second photoelastic fringe image; obtaining shear stress of each micro asperity at different spatial positions of the structure surface based on the second photoelastic fringe image; calculating micro asperity characteristic parameters of each micro asperity in a contact area; defining shear failure evaluation parameters of each micro asperity; calculating deformation height of the micro asperity after plastic deformation under shear at a certain moment; calculating micro asperity characteristic parameters corresponding to each micro asperity after plastic deformation under shear; and calculating roughness evaluation parameters of the structure surface after plastic deformation under shear. By using the method provided by the application, the roughness evolution process of the structure surface in the shear process can be quickly and accurately evaluated based on indoor test.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rock mass evaluation, and in particular to a simulation method and system for evaluating roughness evolution of rock mass structural plane. BACKGROUND

[0002] In rock engineering, the existence of structural plane destroys the integrity of rock mass, resulting in the decrease of strength and stability of rock mass, so that the rock mass is often sheared along the structural plane. Meanwhile, due to the distribution of micro-convexities with different shapes and sizes on the structural plane, the roughness of the structural plane is different in different shear directions, which further affects the macro mechanical properties such as shear strength of the structural plane. Therefore, it is necessary to carry out research on the roughness evolution of the structural plane, which is crucial for engineering safety and stability.

[0003] In the process of implementing the present application, the inventors have found that there are at least the following problems in the prior art:

[0004] During the shear process of the structural plane, only part of the upper and lower structural planes is in contact, resulting in the heterogeneity of shear stress distribution. Meanwhile, the characteristics of the micro-convexities in the contact part are different, resulting in certain differences in shear resistance, and different degrees of deformation and damage of the contact part, which finally leads to the change of the roughness of the structural plane.

[0005] In the past research, scholars have mostly simulated the shear failure process through numerical experiments, but they cannot truly reflect the details in the actual shear process. In comparison, laboratory test is the most direct means for studying the damage evolution of the structural plane in the shear process of the structural plane. However, the existing test devices and methods cannot fully meet the test requirements. Therefore, there are relatively few studies on revealing the roughness evolution law of the structural plane in the shear failure process based on laboratory test.

[0006] Therefore, a simulation method and system for evaluating roughness evolution of rock mass structural plane are needed to at least partially solve the above technical problems. SUMMARY

[0007] In view of this, the embodiments of the present application provide a simulation method and system for evaluating roughness evolution of rock mass structural plane to at least solve one of the problems in the prior art.

[0008] In a first aspect, the embodiments of the present application provide a simulation method for evaluating roughness evolution of rock mass structural plane, which comprises the following steps:

[0009] Based on the pre-obtained replication model corresponding to the natural rock mass to be evaluated containing structural plane and meeting the requirements of mechanical parameters, a photoelastic test is performed to obtain first photoelastic fringe images of the structural plane in the replication model under different analysis mirror polarization angles of a test device used for the photoelastic test; wherein, the replication model comprises an upper module and a lower module combined by an upper structural plane and a lower structural plane having different relief topographies;

[0010] The first photoelastic fringe images are denoised and pretreated by using a bilateral filtering method to obtain second photoelastic fringe images;

[0011] Based on the second photoelastic fringe images, shear stresses τ of each micro asperity at different spatial positions of the structural plane are obtained;

[0012] Based on the shear stresses τ of each micro asperity at different spatial positions of the structural plane, a contact area A between the upper structural plane and the lower structural plane is determined, s the heights h and the corresponding micro asperity inclination angles θ of each micro asperity in the contact area are counted, and micro asperity characteristic parameters F of each micro asperity in the contact area are calculated,

[0013]

[0014] Based on the contact area A s , the structural plane wall surface strength JCS, the normal stress F n applied during the photoelastic test and the micro asperity characteristic parameters F, a shear failure evaluation parameter T of each micro asperity is defined,

[0015]

[0016] wherein, σ n is the normal stress borne by each micro asperity;

[0017] The shear failure evaluation parameter T is compared with a critical shear failure evaluation parameter T cr to determine whether plastic deformation of the micro asperity occurs, when T>T cr , it indicates that the micro asperity has plastic deformation,

[0018]

[0019] wherein, is a critical micro asperity characteristic parameter, and θ * is a critical inclination angle;

[0020] The deformation height Δh of the micro asperity after plastic deformation under shear at a certain moment is calculated,

[0021]

[0022] wherein, P is the normal stress σn The resultant force of the shear stress τ corresponding to the micro asperities; r b The contact radius of the micro asperities and the matrix of the structural plane, E is the equivalent elastic modulus of the contact of the upper and lower modules on the structural plane, and r is the contact range of the micro asperities and the matrix of the structural plane;

[0023] The micro asperity characteristic parameters F1 corresponding to each micro asperity after plastic deformation under shearing are calculated,

[0024]

[0025] θ1=θ-Δθ

[0026] h1=h-Δh

[0027]

[0028] Where Δθ is the angle changed by the micro asperities due to plastic deformation, l is the horizontal length of the micro asperities, h1 is the height of the micro asperities after plastic deformation, and θ1 is the inclination angle of the micro asperities after plastic deformation;

[0029] The structural plane roughness evaluation parameter M after plastic deformation under shearing is calculated,

[0030]

[0031] Where L is the length of the profile line extracted along the length direction of the replication model, all the extracted profile line lengths are set as L, n is the number of profile lines on the two-dimensional profile of the structural plane, m is the number of corresponding micro asperities on each profile line, and Fst represents the tth profile line s th micro asperity characteristic parameter;

[0032] Where 0<M<1, M represents the overall roughness of the structural plane, the greater the value of M, the greater the roughness of the structural plane, and the smaller the value of M, the smaller the roughness of the structural plane.

[0033] In a second aspect, the embodiments of the present application also provide a simulation system for evaluating the roughness evolution of a rock mass structural plane, and the simulation system specifically comprises:

[0034] A test device is used to perform a photoelastic test on a replication model corresponding to a pre-obtained natural rock mass containing a structural plane to be evaluated and meeting the requirements of mechanical parameters, wherein the replication model comprises an upper module and a lower module combined by an upper structural plane and a lower structural plane having different relief topographies; the test device comprises:

[0035] An optical measurement system comprises, in sequence, a laser, a beam expander, a polarizer, a first 1 / 4 wave plate, a second 1 / 4 wave plate, an analyzer, and a CCD camera located on a straight light path;

[0036] A loading system for loading the replication model in the same straight optical path as the optical measurement system, the loading system being arranged between the first 1 / 4 wave plate and the second 1 / 4 wave plate to ensure that the laser light source transmits through the replication model, the loading system comprising a box body having a placing space, a circular ring-shaped pressing cylinder connected to the top plate of the box body and being movable up and down relative to the box body, a supporting cylinder connected to the bottom plate of the box body and being opposite to the pressing cylinder, a lower shear box for supporting the replication model and being detachably lapped on the supporting cylinder, an upper shear box for pressing downward on the replication model, and a horizontal force applying device for horizontally shearing the replication model;

[0037] wherein the pressing cylinder and the supporting cylinder each have a hole for the laser light source to pass through; and

[0038] An electronic device comprising a processor and a memory for storing a computer program, the processor executing the computer program to implement the following steps:

[0039] Obtaining a first photoelastic fringe image of a structural plane in a replication model at different analysis mirror polarization angles of a test device;

[0040] Performing denoising preprocessing on the first photoelastic fringe image by using a bilateral filtering method to obtain a second photoelastic fringe image;

[0041] Based on the second photoelastic fringe image, obtaining shear stress τ of each micro asperity at different spatial positions of the structural plane;

[0042] Based on the shear stress of each micro asperity at different spatial positions of the structural plane, determining a contact area A between the upper structural plane and the lower structural plane, s counting the height h and the corresponding micro asperity inclination angle θ of each micro asperity in the contact area, and calculating the micro asperity characteristic parameter F of each micro asperity in the contact area,

[0043]

[0044] Based on the contact area A s , the structural plane wall surface strength JCS, the normal stress F n applied during the photoelastic test, and the micro asperity characteristic parameter F, defining a shear failure evaluation parameter T of each micro asperity,

[0045]

[0046] wherein σ n is the normal stress borne by each micro asperity;

[0047] Comparing the shear failure evaluation parameter T with a critical shear failure evaluation parameter T cr to determine whether plastic deformation occurs in the micro asperity, when T>Tcr t represents that the micro asperity is plastically deformed,

[0048]

[0049] wherein, is a critical micro asperity characteristic parameter, θ * is a critical inclination angle;

[0050] The deformation height Δh of the micro asperity after plastic deformation under shearing at a certain time is calculated,

[0051]

[0052] wherein, P is the normal stress σ n and the shear stress τ corresponding to the micro asperity; r b is the contact radius of the micro asperity and the base of the structural surface, E is the equivalent elastic modulus of the contact between the upper and lower modules of the structural surface, and r is the contact range of the micro asperity and the base of the structural surface;

[0053] The micro asperity characteristic parameter F1 corresponding to each micro asperity after plastic deformation under shearing is calculated,

[0054]

[0055] θ1 = θ - Δθ

[0056] h1 = h - Δh

[0057]

[0058] wherein, Δθ is the angle changed by the micro asperity due to plastic deformation, l is the horizontal length of the micro asperity, h1 is the height of the micro asperity after plastic deformation, and θ1 is the inclination angle of the micro asperity after plastic deformation;

[0059] The structural surface roughness evaluation parameter M after plastic deformation under shearing is calculated,

[0060]

[0061] wherein, L is the length of the profile line extracted along the length direction of the replicated model, all the extracted profile line lengths are set as L, n is the number of profile lines on the two-dimensional profile of the structural surface, m is the number of corresponding micro asperities on each profile line, and Fst represents the micro asperity characteristic parameter of the s-th micro asperity on the t-th profile line.

[0062] wherein, 0 < M < 1, M represents the overall roughness degree of the structural surface, the greater the value of M, the greater the roughness degree of the structural surface, and the smaller the value of M, the smaller the roughness degree of the structural surface.

[0063] According to the simulation method of the embodiment of the present application, in order to realize the evaluation of the roughness evolution of the structural plane of the natural rock mass under shear, on the basis of shearing the structural plane model (i.e. the replication model) of the rock mass, the photoelastic test is carried out on the structural plane model based on the indoor test, the relevant photoelastic fringe patterns are obtained, the shear stress of each microconvex body at different spatial positions of the structural plane is obtained, the correlation among the shear stress, the contact area and the roughness evaluation parameter of the structural plane is established, and finally the roughness evaluation parameter of the structural plane after plastic deformation under shear is obtained, so that the roughness evolution of the structural plane of the natural rock mass is quickly and accurately evaluated.

[0064] Additional advantages, objects, and features of the application will be set forth in part by the description that follows, and will become apparent to those skilled in the art upon examination of the following detailed description and drawings in which

[0065] Those skilled in the art will appreciate that the objects and advantages of the application can be accomplished by the devices and processes described in detail herein, and that the application can be used with a variety of other devices and processes without departing from the spirit or scope of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0066] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description, serve to explain the principles of the application. The components in the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the application. For purposes of clarity and understanding, it is expressly intended that some portions of the drawings be shown exaggerated in scale, or out of proportion, to illustrate aspects of the application. In the drawings:

[0067] Figure 1 Flow chart of the simulation method for evaluating the roughness evolution of the structural plane of the rock mass according to an embodiment of the present application;

[0068] Figure 2 Schematic block diagram of the simulation system for evaluating the roughness evolution of the structural plane of the rock mass according to an embodiment of the present application;

[0069] Figure 3 Schematic diagram of the relative position distribution among the parts in the simulation system for evaluating the roughness evolution of the structural plane of the rock mass according to an embodiment of the present application;

[0070] Figure 4 Schematic diagram of the loading system in the simulation system for evaluating the roughness evolution of the structural plane of the rock mass according to an embodiment of the present application, in which the relative position of the replication model in the loading system is shown;

[0071] Figure 5Another angle view of the loading system in the simulation system for evaluating roughness evolution of rock mass structure surface according to an embodiment of the present application, in which the upper and lower shear boxes are omitted;

[0072] Figure 6 A schematic view of the simulation system for evaluating roughness evolution of rock mass structure surface according to an embodiment of the present application, in which the replica model is placed in the upper and lower shear boxes and installed in place; and

[0073] Figure 7 A schematic view of the simulation system for evaluating roughness evolution of rock mass structure surface according to an embodiment of the present application, in which the replica model is placed in the upper and lower shear boxes and installed in place; and Figure 6 A schematic view of the simulation system for evaluating roughness evolution of rock mass structure surface according to an embodiment of the present application, in which the replica model is placed in the upper and lower shear boxes and installed in place; and

[0074] A schematic view of the simulation system for evaluating roughness evolution of rock mass structure surface according to an embodiment of the present application, in which the replica model is placed in the upper and lower shear boxes and installed in place; and

[0075] 200, simulation system;

[0076] 20, test device;

[0077] 220, optical measurement system; 221, laser; 222, beam expander; 223, polarizer; 224, first 1 / 4 wave plate; 225, second 1 / 4 wave plate; 226, analyzer; 227, CCD camera;

[0078] 240, loading system; 241, box; 242, pressurizing cylinder; 243, supporting cylinder; 244, upper shear box; 245, lower shear box; 246, loading head mechanism; 247, limiting mechanism; 248, hole; 249, handle;

[0079] 30, electronic device;

[0080] 310, processor;

[0081] 320, memory;

[0082] 400, replica model;

[0083] 410, upper module;

[0084] 420, lower module. DETAILED DESCRIPTION

[0085] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments and drawings. Herein, the illustrative embodiments of the present application and their descriptions are used to explain the present application but not to limit the present application.

[0086] Herein, it also needs to be noted that, in order to avoid the present application being obscured by unnecessary details, only the structures and / or processing steps closely related to the solutions according to the present application are shown in the drawings, and other details not closely related to the present application are omitted.

[0087] It should be emphasized that the term "comprises / comprising" when used in this specification is taken to specify the presence of stated features, elements, steps or components but does not preclude the presence or addition of one or more other features, elements, steps, components or groups thereof.

[0088] It should also be noted that the term "connected" is used herein to include direct connection between two components and indirect connection between two components through intervening components.

[0089] Hereinafter, embodiments of the present application will be described with reference to the accompanying drawings. In the drawings, like reference numerals designate like or similar components, or like or similar steps.

[0090] Firstly, the simulation method 100 for evaluating the roughness evolution of rock mass structural plane according to the embodiments of the present application will be described with reference to Figure 1 As shown in FIG. 1, the simulation method 100 can include the following steps: Figure 1

[0091] At step S110, based on the pre-obtained replication model of the natural rock mass with structural plane to be evaluated which meets the requirements of mechanical parameters, photoelastic test is performed to obtain first photoelastic fringe images of the structural plane in the replication model under different analysis mirror polarization angles of a test device used for performing the photoelastic test; wherein the replication model includes an upper module and a lower module combined by an upper structural plane and a lower structural plane having different relief topographies.

[0092] At step S120, the first photoelastic fringe images are denoised and pre-processed by using a bilateral filtering method to obtain second photoelastic fringe images.

[0093] At step S130, based on the second photoelastic fringe images, shear stresses τ of each micro asperity at different spatial positions of the structural plane are obtained.

[0094] At step S140, based on the shear stresses τ of each micro asperity at different spatial positions of the structural plane, a contact area between the upper structural plane and the lower structural plane is determined, and an area A of the contact area is determined. s The height h and the corresponding micro asperity inclination angle θ of each micro asperity in the contact area are counted, and a micro asperity characteristic parameter F of each micro asperity in the contact area is calculated.

[0095]

[0096] At step S150, based on the area A of the contact area, the structural plane wall surface strength JCS, the normal stress F applied when performing the photoelastic test, and the micro asperity characteristic parameter F, a shear failure evaluation parameter T of each micro asperity is defined. s n

[0097] ​​​

[0098] wherein σ n is the normal stress borne by each micro asperity.

[0099] In step S160, the shear failure evaluation parameter T and the critical shear failure evaluation parameter T cr are compared in size to determine whether the micro asperity has undergone plastic deformation, when T > T cr , it indicates that the micro asperity has undergone plastic deformation,

[0100]

[0101] wherein, is the critical micro asperity characteristic parameter, θ * is the critical inclination angle.

[0102] In step S170, the deformation height Δh of the micro asperity after plastic deformation under shear at a certain time is calculated,

[0103]

[0104] wherein P is the normal stress σ n and the shear stress τ borne by the micro asperity corresponding to the micro asperity; r b is the contact radius of the micro asperity and the base of the structural surface, E is the equivalent elastic modulus of the contact between the upper and lower modules of the structural surface, and r is the contact range of the micro asperity and the base of the structural surface.

[0105] In step S180, the micro asperity characteristic parameter F1 of each micro asperity after plastic deformation under shear is calculated,

[0106]

[0107] θ1 = θ - Δθ

[0108] h1 = h - Δh

[0109]

[0110] wherein Δθ is the angle changed by the micro asperity due to plastic deformation, l is the horizontal length of the micro asperity, h1 is the height of the micro asperity after plastic deformation, and θ1 is the inclination angle of the micro asperity after plastic deformation.

[0111] In step S190, the structural surface roughness evaluation parameter M after plastic deformation under shear is calculated,

[0112]

[0113] Wherein, L is the length of the profile line extracted along the length direction of the replication model, all the extracted profile line lengths are set as L, n is the number of profile lines on the two-dimensional profile of the structural surface, m is the number of corresponding micro-convexes on each profile line, and Fst represents the characteristic parameter of the s-th micro-convex on the t-th profile line.

[0114] Wherein, 0 < M < 1, M represents the overall roughness degree of the structural surface, the greater the value of M is, the greater the roughness degree of the structural surface is, and the smaller the value of M is, the smaller the roughness degree of the structural surface is.

[0115] In the embodiment of the present application, first, the replication model meeting the mechanical parameter requirement is subjected to photoelastic test to obtain the first photoelastic fringe image of the structural surface in the replication model under different analysis mirror polarization angles, the first photoelastic fringe image is subjected to denoising pretreatment to obtain the second photoelastic fringe image, then the shear stress of each micro-convex at different spatial positions of the structural surface is obtained based on the second photoelastic fringe image, the micro-convex characteristic parameter of each micro-convex in the contact area is calculated, the shear failure evaluation parameter of each micro-convex is defined, then it is judged whether the micro-convex is subjected to plastic deformation, the deformation height of the micro-convex after plastic deformation under shear at a certain moment is calculated, and the micro-convex characteristic parameter corresponding to each micro-convex after plastic deformation under shear is calculated; finally, the roughness evaluation parameter of the structural surface after plastic deformation under shear is calculated.

[0116] It can be known from the description of the above process that, according to the simulation method 100 of the embodiment of the present application, the roughness evaluation parameter of the structural surface after plastic deformation under shear can be obtained based on the indoor shear test, and the roughness evolution process of the structural surface in the shear process can be quickly and accurately evaluated.

[0117] The content of each step of the simulation method 100 according to the embodiment of the present application will be specifically described below.

[0118] In the embodiment of the present application, the replication model meeting the mechanical parameter requirement is subjected to photoelastic test in step S110 to obtain the first photoelastic fringe image of the structural surface in the replication model under different analysis mirror polarization angles.

[0119] First, the following steps can also be performed before step S110 is performed:

[0120] The replication model meeting the mechanical parameter requirement is made. The replication model can be specifically made by:

[0121] A rock mass sample of a natural rock mass to be evaluated containing structural planes is collected, point cloud information of the structural plane topography of the rock mass sample is obtained, and a three-dimensional digital model of the structural plane is established. For example, a three-dimensional laser scanner can be used to scan the natural structural plane to obtain the point cloud information of the structural plane topography. According to the obtained point cloud information of the natural structural plane topography, the three-dimensional curved surface is projected in two directions, respectively, and is imported into a 3D printing control system to generate a completely coupled three-dimensional digital model of the structural plane, and a replication model is obtained by 3D printing according to the three-dimensional digital model of the structural plane. For example, using the 3D printing control system to print layer by layer from top to bottom, the size of the replication model can be length x width x height = 100 mm x 100 mm x 20 mm, or other appropriate sizes. After printing is completed, in order to increase the transparency of the model, the model can be polished and polished until good transparency and uniformity are achieved.

[0122] Among them, the material for 3D printing model needs to meet two requirements: one is that the model material and the rock mass sample material have a certain similarity relationship, and the other is that the transparent material can produce stress birefringence effect. For example, a photosensitive resin material can be selected to carry out the test.

[0123] In order to verify whether the replication model meets the requirements, the same condition physical and mechanical test is carried out on the rock mass sample and the replication model, and the mechanical parameter values of the rock mass sample and the replication model are obtained respectively. The physical and mechanical test can include uniaxial compression test and / or acoustic wave test, or triaxial compression test and / or acoustic wave test. The mechanical parameter values can be uniaxial compressive strength, Poisson's ratio, dynamic elastic modulus, dynamic shear modulus, dynamic Lame coefficient, dynamic bulk modulus, cohesion, internal friction angle and / or friction coefficient, etc.

[0124] When the error between the mechanical parameter values of the rock mass sample and the replication model meets the preset condition, the replication model that meets the mechanical parameter requirements is obtained. For example, the error between the mechanical parameter value P T of the rock mass sample and the mechanical parameter value P S of the replication model meets the preset condition, which means that P T -P S ≤α*P T , where -5%≤α≤5%.

[0125] When the error between the mechanical parameter values of the rock mass sample and the replication model does not meet the preset condition, the printing scheme is adjusted to re-perform 3D printing until a replication model that meets the requirements is obtained. Among them, the replication model includes an upper module and a lower module combined by an upper structural plane and a lower structural plane with different topography differences.

[0126] Specifically, a photoelastic test is carried out on the replication model by using a laboratory test device to obtain a first photoelastic fringe image of the structural plane in the replication model under different analysis mirror polarization angles of the test device.

[0127] wherein the reference Figure 3 , the test device can include an optical measurement system and a loading system. The optical measurement system can include a laser, a beam expander, a polarizer, a first 1 / 4 wave plate, a second 1 / 4 wave plate, an analyzer, and a CCD camera. The CCD camera can be connected to an electronic device, such as a computer (or commonly known as a computer), to achieve image processing and can directly observe the internal structure surface photoelastic fringe through the display screen.

[0128] wherein the reference Figures 4 to 7 , the loading system can include a box with a placing space, a circular ring-shaped pressure cylinder connected to the top plate of the box and movable up and down relative to the box, a support cylinder connected to the bottom plate of the box and opposite to the pressure cylinder, a lower shear box for supporting the replica model and detachably lapped on the support cylinder, an upper shear box for pressing down on the replica model, and a horizontal force applying device for horizontally shearing the replica model. The specific form of the horizontal force applying device is not limited.

[0129] In order to ensure the smooth progress of the test, the optical path continuity must be met first, which requires the positions of all devices to be adjusted to the same straight line to ensure that the laser light source at the top of the test device can pass through the replica model. Therefore, the inside of the pressure cylinder and the support cylinder has a relative aligned hole for the laser light source to pass through.

[0130] wherein the lower shear box can be an L-shaped structure with a right block protruding upward at the right end. The width (front-to-back direction) of the lower shear box is adapted to the width of the replica model. The upper shear box can be a door-shaped structure with an inner wall surface capable of closely abutting the replica model and a left block protruding downward at the left end. That is, there is a clamping edge extending vertically downward in the front-to-back direction, and the left end has a left block.

[0131] The horizontal force applying device can include a loading head mechanism connected to the left side plate of the box and movable horizontally relative to the box, and a limiting mechanism connected to the right side plate of the box for abutting against the right block. The loading head mechanism is used to apply a horizontal shear force, and the size of the applied horizontal shear force can be measured by a dynamometer. The specific form of the loading head mechanism is not limited. The limiting mechanism mainly limits the movement of the lower shear box during shearing. The specific form of the limiting mechanism is not limited.

[0132] The pressure cylinder can be connected to the top plate of the box via internal and external threads. The outer side wall of the pressure cylinder is horizontally provided with a handle for driving the rotation of the pressure cylinder. The vertical pressure mode is vertical screw pressure, which is achieved by rotating the handles on both sides, thereby realizing vertical load pressure, and the size of the applied normal pressure can be obtained by a dynamometer. The pressure cylinder is designed in a circular ring shape, which can ensure the penetration of the optical path and uniform application of pressure.

[0133] When the photoelastic experiment is performed, the replica model is placed in the upper and lower shear boxes and installed in place, i.e., the right end of the replica model abuts against the right stop block, the inner wall surface (the inner top surface and the inner side surfaces in front and back) of the upper shear box abuts against the replica model, the right stop block abuts against the lower module, and the left stop block abuts against the upper module. For reference, see Figure 6 .

[0134] The pressure cylinder is rotated downward to realize normal loading on the replica model, so that the replica model enters a constant pressure state. The loading head mechanism is rotated horizontally to push the left stop block, i.e., a certain horizontal shear force is applied to the replica model (the upper module) at the same time, so as to realize shearing of the replica model. The loading of the shear force has a certain limitation and cannot exceed the shear strength of the structural surface.

[0135] The rotation angles of the polarizer and the analyzer are changed, and six phase shift photoelastic fringe images (i.e., first photoelastic fringe images) under different polarization angles of the analyzer are captured by the CCD camera. For example, six phase shift photoelastic fringe images are obtained by changing the polarization angle by 45° each time.

[0136] The upper shear box and the lower shear box can be made of acrylic plates, which not only have a certain pressure resistance but also fully meet the requirement of unobstructed light path for photoelastic experiments.

[0137] In the embodiment of the present application, the first photoelastic fringe image is preprocessed by using the bilateral filtering method for denoising in step S120, to obtain a second photoelastic fringe image with clearer fringe contour lines.

[0138] Specifically, the spatial domain kernel represents the Euclidean distance between a point (p, q) in the neighborhood and a center point (i, j),

[0139]

[0140] σs is the standard deviation of the function.

[0141] wherein a pixel region of, for example, 3x3 or 5x5 in the first photoelastic fringe image can be randomly selected to determine the neighborhood and the center point.

[0142] The range kernel represents the absolute value of the difference between the gray value f(p, q) of a point (p, q) in the neighborhood and the gray value f(i, j) of the center point (i, j),

[0143]

[0144] σr is the standard deviation of the function.

[0145] The weight coefficient is the product w of the spatial domain kernel and the range kernel,

[0146] w(i,j,p,q)=G σs (i,j,p,q)*Gσr (i,j,p,q).

[0147] The new pixel value g of the center point in the neighborhood is obtained by weighting the gray value f in the neighborhood with its weight w.

[0148]

[0149] By iterating through all pixels in each of the first photoelastic stripe images, the corresponding second photoelastic stripe image is obtained.

[0150] In the embodiments of this application, in step S130, the shear stress τ of each micro-protrusion at different spatial locations of the structural surface is obtained based on the second photoelastic fringe image.

[0151] For example, all second photoelastic fringe images can be unwrapped, and the shear stress of each micro-protrusion at different spatial locations on the structural surface can be obtained based on the shear stress difference method and the six-step phase shift method. The unwrapping method, as well as the shear stress difference method and the six-step phase shift method, are all existing technologies in the field and will not be described in detail here.

[0152] Finally, the shear stress τ of each micro-protrusion at different spatial locations on the structural surface is obtained, and the heterogeneous distribution of shear stress on the structural surface is thus determined.

[0153] In the embodiments of this application, step S140 calculates the micro-protrusion characteristic parameters F of each micro-protrusion within the contact area.

[0154] Specifically, since shear stress distribution only occurs at the points of contact, areas with higher shear stress (areas where shear stress exceeds a set threshold) often correspond to the contact area, based on the shear stress and its distribution. Therefore, the contact area between the upper and lower structural surfaces can be deduced. Based on the contact area between the upper and lower structural surfaces, the contact area A is determined. s For example, it can be obtained directly through extraction. The height h and corresponding tilt angle θ of each micro-protrusion within the contact area are statistically analyzed, and the micro-protrusion characteristic parameters F of each micro-protrusion within the contact area are calculated.

[0155]

[0156] In the embodiments of this application, step S150 defines the shear failure evaluation parameter T for each micro-protrusion.

[0157] Based on the contact area A s , structural wall strength JCS, and normal stress F applied during photoelastic testing n The shear failure evaluation parameter T for each micro-protrusion is defined by the normal stress applied by the pressure cylinder (i.e., the normal stress applied by the pressure cylinder) and the characteristic parameter F of the micro-protrusion.

[0158]

[0159] wherein σ n is the normal stress borne by each micro asperity.

[0160] In the embodiments of the present application, it is determined in step S160 whether the micro asperity has undergone plastic deformation.

[0161] Specifically, under certain normal stress and wall strength conditions, there is a critical inclination angle θ * of the structural surface when shearing, i.e., there is a critical micro asperity characteristic parameter F θ* When the angle is less than this angle, the micro asperity has strong resistance to the shearing stress; and when the angle is greater than this angle, the micro asperity has weakened resistance to the shearing stress.

[0162] The critical shearing failure evaluation parameter T cr is calculated.

[0163]

[0164] The shearing failure evaluation parameter T obtained in the foregoing and the critical shearing failure evaluation parameter T cr are compared in size, and it is determined whether the micro asperity has undergone plastic deformation. If T>T cr , it indicates that the micro asperity has undergone plastic deformation. If T≤T cr , it indicates that the micro asperity has undergone elastic deformation.

[0165] Since elastic deformation does not cause the micro asperity to fail, plastic deformation is mainly considered.

[0166] In the embodiments of the present application, the deformation height Δh of the micro asperity after undergoing plastic deformation under shearing at a certain time is calculated in step S170.

[0167] wherein the deformation height Δh of the micro asperity after undergoing plastic deformation under shearing at a certain time,

[0168]

[0169] wherein P is the resultant force of the normal stress σ n borne by the micro asperity and the shearing stress τ corresponding to the micro asperity; r b is the contact radius of the micro asperity and the base of the structural surface, E is the equivalent elastic modulus of the contact between the upper and lower modules of the structural surface, and r is the contact range of the micro asperity and the base of the structural surface.

[0170] In the embodiments of the present application, the micro asperity characteristic parameter f1 corresponding to each micro asperity after undergoing plastic deformation under shearing is calculated in step S180.

[0171] Specifically, the micro asperity characteristic parameter f1 corresponding to each micro asperity after undergoing plastic deformation under shearing,

[0172]

[0173] θ1 = θ - Δθ

[0174] h1 = h - Δh

[0175]

[0176] Wherein, Δθ is the angle of the micro asperity changed due to plastic deformation, l is the horizontal length of the micro asperity, h1 is the height of the micro asperity after plastic deformation, θ1 is the inclination angle of the micro asperity after plastic deformation.

[0177] It should be noted that the micro asperity characteristic parameter F1 here refers to the micro asperity characteristic parameter corresponding to a certain or single micro asperity, which is the data after determining which micro asperity of which section line, that is, the micro asperity characteristic parameter Fst of the s-th micro asperity of the t-th section line.

[0178] In the embodiment of the present application, the structural surface roughness evaluation parameter M after plastic deformation under shearing is calculated in step S190.

[0179] Specifically, the structural surface roughness evaluation parameter M after plastic deformation under shearing is calculated according to the following formula:

[0180]

[0181] Wherein, L is the length of the section line extracted along the length direction of the replica model, all the extracted section line lengths are set as L, n is the number of section lines on the two-dimensional section of the structural surface, m is the number of corresponding micro asperities on each section line, and Fst represents the micro asperity characteristic parameter of the s-th micro asperity of the t-th section line.

[0182] Wherein, 0 < M < 1, M represents the overall roughness of the structural surface, the larger the value of M, the greater the roughness of the structural surface, and the smaller the value of M, the smaller the roughness of the structural surface.

[0183] During shearing, the change of the structural surface roughness will also cause the change of the contact area, changing the distribution of the shearing stress.

[0184] Such a cycle can establish the correlation between the shearing stress, the contact area and the structural surface roughness evaluation parameter.

[0185] Based on the above description, according to the simulation method of the embodiment of the present application, on the basis of shearing the replication model, the photoelastic test is carried out on the structural surface model based on the indoor test, the related photoelastic fringe pattern is obtained, the shear stress of each microconvex body at different spatial positions of the structural surface is determined, the correlation among the shear stress, the contact area and the structural surface roughness evaluation parameter is established, and finally the structural surface roughness evaluation parameter after plastic deformation under shearing is obtained, so that the rapid and accurate evaluation of the structural surface roughness evolution of the natural rock mass is realized.

[0186] In addition, with reference to Figure 2 , the present application also provides a simulation system 200 for evaluating the structural surface roughness evolution of a rock mass. The simulation system 200 can include an electronic device 30 and a test device 20. The electronic device 30 can include a processor 310 and a memory 320. The memory 320 stores an executable computer program.

[0187] Specifically, the test device 20 is used to perform a photoelastic test on a replication model 400 corresponding to the natural rock mass to be evaluated containing a structural surface, which meets the requirements of mechanical parameters, based on the replication model 400 obtained in advance. Figure 6 and Figure 7 The replication model 400 includes an upper module 410 and a lower module 420 combined by an upper structural surface and a lower structural surface with different undulating topographies.

[0188] As shown in Figure 3 , the test device 20 can include an optical measurement system 220 and a loading system 240 for loading the replication model 400.

[0189] Specifically, the optical measurement system 220 can include a laser 221, a beam expander 222, a polarizer 223, a first 1 / 4 wave plate 224, a second 1 / 4 wave plate 225, an analyzer 226 and a CCD camera 227 arranged in sequence on a straight light path. The CCD camera 227 can be signal connected to the electronic device 30.

[0190] The loading system 240 and the components of the optical measurement system 220 are located on the same straight light path. The loading system 240 is arranged between the first 1 / 4 wave plate 224 and the second 1 / 4 wave plate 225 to ensure that the laser 221 light source transmits through the replication model 400.

[0191] With reference to Figure 4 , Figure 5The loading system 240 can include a box 241 with a space for placing, a circular pressure cylinder 242 connected to the top plate of the box 241 and movable up and down relative to the box 241, a support cylinder 243 connected to the bottom plate of the box 241 and opposite to the pressure cylinder 242, a lower shear box 245 for supporting the replica model 400 and detachably lapping on the support cylinder 243, an upper shear box 244 for pressing down on the replica model 400, and a horizontal force applying device for horizontally shearing the replica model 400. The box 241 can be a square box 241, which can have one side connected to the outside for implementation and observation.

[0192] The pressure cylinder 242 and the support cylinder 243 each have a hole 248 for the laser 221 light source to pass through.

[0193] In the preferred embodiment, in order to realize the up and down movement of the pressure cylinder 242, the pressure cylinder 242 can be screwed to the top plate of the box 241 through internal and external threads. The outer side wall of the pressure cylinder 242 is horizontally provided with a handle 249 for driving the rotation of the pressure cylinder 242, and the pressure cylinder 242 is driven to move up and down by rotating the handle 249.

[0194] Preferably, the upper shear box 244 and the lower shear box 245 can be shear boxes made of acrylic plate material.

[0195] Further, the lower shear box 245 can be an L-shaped structure with a right block protruding upward at the right end. The upper shear box 244 can be a door-shaped structure with an inner wall surface capable of closely abutting the replica model and a left block protruding downward at the left end.

[0196] The horizontal force applying device can include a loading head mechanism 246 connected to the left side plate of the box 241 and horizontally movable relative to the box 241, and a limiting mechanism 247 connected to the right side plate of the box 241 and used for abutting against the right block. The specific forms of the loading head mechanism 246 and the limiting mechanism 247 are not limited.

[0197] When performing the photoelastic test, the right block abuts against the lower model 420, the left block abuts against the upper model 410, and the loading head mechanism 246 horizontally pushes the left block to realize shearing.

[0198] The processor executes the computer program to realize the following steps:

[0199] Obtaining a first photoelastic fringe image of a structural plane in a replica model under different analysis mirror polarization angles of a test device.

[0200] The first photoelastic fringe image is denoised and preprocessed by a bilateral filtering method to obtain a second photoelastic fringe image.

[0201] The shear stress τ of each micro asperity at different spatial positions of the structural plane is obtained based on the second photoelastic fringe image.

[0202] The contact area A between the upper structural plane and the lower structural plane is determined based on the shear stress of each micro asperity at different spatial positions of the structural plane, and the contact area A is determined. s The height h and the corresponding micro asperity inclination angle θ of each micro asperity in the contact area are counted, and the micro asperity characteristic parameter F of each micro asperity in the contact area is calculated.

[0203]

[0204] The shear failure evaluation parameter T of each micro asperity is defined based on the contact area A s , the wall surface strength JCS of the structural plane, the normal stress F n applied during the photoelastic test, and the micro asperity characteristic parameter F.

[0205]

[0206] Wherein, σ n is the normal stress borne by each micro asperity.

[0207] The shear failure evaluation parameter T is compared with the critical shear failure evaluation parameter T cr , to determine whether the micro asperity has plastic deformation, when T>T cr , it means that the micro asperity has plastic deformation.

[0208]

[0209] Wherein, is the critical micro asperity characteristic parameter, and θ * is the critical inclination angle.

[0210] The deformation height Δh of the micro asperity after plastic deformation under shear at a certain time is calculated.

[0211]

[0212] Wherein, P is the resultant force of the normal stress σ n and the shear stress τ corresponding to the micro asperity borne by the micro asperity; r b is the contact radius of the micro asperity and the structural plane matrix, E is the equivalent elastic modulus of the upper and lower modules of the structural plane in contact, and r is the contact range of the micro asperity and the structural plane matrix.

[0213] The micro asperity characteristic parameter F1 corresponding to each micro asperity after plastic deformation under shear is calculated.

[0214]

[0215] θ1=θ-Δθ

[0216] h1 = h - Ah

[0217]

[0218] wherein, Ah is the change of the height of the micro asperity, h is the height of the micro asperity before plastic deformation, and h1 is the height of the micro asperity after plastic deformation.

[0219] calculating a roughness evaluation parameter M of the structural plane after plastic deformation under shearing,

[0220]

[0221] wherein, L is the length of the profile line extracted along the length direction of the replication model, all the extracted profile line lengths are set as L, n is the number of profile lines on the two-dimensional profile of the structural plane, m is the number of corresponding micro asperities on each profile line, and Fst represents the characteristic parameter of the s-th micro asperity on the t-th profile line.

[0222] wherein, 0 < M < 1, M represents the overall roughness degree of the structural plane, the greater the value of M, the greater the roughness degree of the structural plane, and the smaller the value of M, the smaller the roughness degree of the structural plane.

[0223] In a third aspect, the present application further provides a simulation method for evaluating the roughness evolution of a rock mass structural plane. The simulation method can include the following steps:

[0224] In step S510, a first photoelastic fringe image of the structural plane under different analysis mirror polarization angles of the test device in the replication model obtained by performing a photoelastic test on the replication model corresponding to the natural rock mass with a structural plane to be evaluated and meeting the requirements of mechanical parameters is acquired.

[0225] In step S520, a second photoelastic fringe image is obtained by performing denoising preprocessing on the first photoelastic fringe image by using a bilateral filtering method.

[0226] In step S530, the second photoelastic fringe image is subjected to unwrapping processing, and based on the shearing stress difference method and the six-step phase shift method, the shearing stress τ of each micro asperity at different spatial positions of the structural plane is obtained.

[0227] In step S540, the contact area between the upper structural plane and the lower structural plane is determined based on the shearing stress of each micro asperity at different spatial positions of the structural plane, and the contact area A is determined. s The height h and the corresponding micro asperity inclination angle θ of each micro asperity in the contact area are counted, and the micro asperity characteristic parameter F of each micro asperity in the contact area is calculated.

[0228]

[0229] At step S550, based on the contact area A s , the joint plane wall surface strength JCS, the normal stress F n applied when performing the photo-elastic test, and the micro-asperity characteristic parameter F, a shear failure evaluation parameter T of each micro-asperity is defined,

[0230]

[0231] wherein σ n is the normal stress borne by each micro-asperity.

[0232] At step S560, the shear failure evaluation parameter T is compared with a critical shear failure evaluation parameter T cr , and it is determined whether the micro-asperity has undergone plastic deformation, when T > T cr , it is determined that the micro-asperity has undergone plastic deformation,

[0233]

[0234] wherein, is the critical micro-asperity characteristic parameter, θ * is the critical inclination angle.

[0235] At step S570, the deformation height Δh of the micro-asperity after plastic deformation under shear at a certain time is calculated,

[0236]

[0237] wherein P is the resultant force of the normal stress σ n borne by the micro-asperity and the shear stress τ corresponding to the micro-asperity; r b is the contact radius of the micro-asperity with the joint plane matrix, E is the equivalent elastic modulus of the upper and lower modules in contact on the joint plane, and r is the contact range of the micro-asperity with the joint plane matrix.

[0238] At step S580, the micro-asperity characteristic parameter F1 corresponding to each micro-asperity after plastic deformation under shear is calculated,

[0239]

[0240] θ1 = θ - Δθ

[0241] h1 = h - Δh

[0242]

[0243] wherein Δθ is the angle changed by the micro-asperity due to plastic deformation, 1 is the horizontal length of the micro-asperity, h1 is the height of the micro-asperity after plastic deformation, and θ1 is the inclination angle of the micro-asperity after plastic deformation.

[0244] At step S590, a structural surface roughness evaluation parameter M after plastic deformation under shearing is calculated,

[0245]

[0246] wherein L is the length of the profile line extracted along the length direction of the replication model, all the extracted profile line lengths are set as L, n is the number of profile lines on the two-dimensional profile of the structural surface, m is the number of corresponding microconvexes on each profile line, and Fst represents the tth profile line s th microconvex feature parameter;

[0247] wherein 0 < M < 1, M represents the overall roughness degree of the structural surface, the greater the M value, the greater the roughness degree of the structural surface, and the smaller the M value, the smaller the roughness degree of the structural surface.

[0248] wherein the specific content of steps S510 to S590 can refer to the content of the foregoing embodiments, which will not be repeated here.

[0249] In a fourth aspect, according to the embodiments of the present application, the present application further provides an electronic device. The electronic device includes a memory and a processor.

[0250] wherein the memory is configured to store computer executable instructions.

[0251] The processor is configured to execute the computer executable instructions stored in the memory, and implement the simulation method of steps S510 to S590.

[0252] In a fifth aspect, according to the embodiments of the present application, the present application further provides a storage medium, on which a computer program is stored, and the computer program is configured to execute the simulation method of steps S510 to S590 of the embodiments of the present application when the computer program is run by a processor. The storage medium may, for example, include a memory card of a smart phone, a storage component of a tablet computer, a hard disk of a personal computer, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a portable compact disc read-only memory (CD-ROM), a USB memory, or any combination of the above storage media. The computer readable storage medium can be any combination of one or more computer readable storage media.

[0253] In a sixth aspect, according to the embodiments of the present application, the present application further provides a computer program product, including computer instructions, which, when executed by a processor, implement the simulation method of steps S510 to S590 of the embodiments of the present application.

[0254] wherein the electronic device can include one or more processors, one or more memories. The executable computer program, when executed by the processor, causes the processor to execute the steps described above.

[0255] The processor can be a central processing unit (CPU) or other form of processing unit having data processing and / or instruction executing capabilities, and can control other components in the electronic device to perform desired functions.

[0256] The memory can include one or more computer program products that can include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory, for example, can include random access memory (RAM), cache memory, and / or the like. The non-volatile memory, for example, can include read only memory (ROM), hard disk, flash memory, and / or the like. One or more computer program instructions can be stored on the computer-readable storage media, and the processor can execute the program instructions to implement the client functions (implemented by the processor) in the embodiments of the present application described herein and / or other desired functions. Various application programs and various data, such as various data used and / or generated by the application programs, and the like, can also be stored in the computer-readable storage media.

[0257] The electronic device can also include an input device (not shown) and an output device (not shown), which are interconnected through a bus system (not shown) and / or other forms of connection mechanisms. It should be noted that, Figure 2 The components and structures of the electronic device shown are only exemplary and are not limiting, and the electronic device can also have other components and structures as needed.

[0258] The input device can be a device used by a user to input instructions, and can include one or more of a keyboard, a mouse, a microphone, a touch screen, and the like. In addition, the input device can also be any interface that receives information.

[0259] The output device can output various information (such as images or sounds) to the outside (such as a user), and can include one or more of a display, a speaker, and the like. In addition, the output device can also be any other device with output functions.

[0260] Exemplarily, the electronic device can be a terminal device (such as a mobile phone), a tablet computer, a notebook computer, an ultra-mobile personal computer (UMPC), a handheld computer, a netbook, a personal digital assistant (PDA), a wearable device (such as a smart watch, smart glasses, or a smart helmet, etc.), an augmented reality (AR) device, a virtual reality (VR) device, a smart home device, a vehicle-mounted computer, and the like, and the embodiments of the present application do not make any limitation thereto.

[0261] Although the example embodiments have been described herein with reference to the accompanying drawings, it is to be understood that the above description is merely of a preferred embodiment or of a part of a preferred embodiment of the application and is not intended to limit the scope of the application. Various changes and modifications can be made thereto by those of ordinary skill in the art without departing from the scope and spirit of the application. All such changes and modifications are intended to be included within the scope of the application as defined in the appended claims.

[0262] The above description is merely a specific implementation or a description of a specific implementation of the present application, and the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, and all such changes and replacements are intended to be included in the protection scope of the present application. The protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A simulation method for evaluating roughness evolution of structural planes in rock mass, characterized in that, The simulation method comprises: Based on the pre-obtained replication model of the natural rock mass with structural plane to be evaluated and meeting the requirements of mechanical parameters, a photoelastic test is performed to obtain first photoelastic fringe images of the structural plane in the replication model under different analysis mirror polarization angles of a test device used for performing the photoelastic test; wherein the replication model comprises an upper module and a lower module combined by an upper structural plane and a lower structural plane having different undulating topographies; The first photoelastic fringe images are denoised and pretreated by using a bilateral filtering method to obtain second photoelastic fringe images; Based on the second photoelastic fringe images, shear stresses τ of each micro asperity at different spatial positions of the structural plane are obtained; determining the contact area A between the upper structural surface and the lower structural surface based on the shear stress of each microconvex body at different spatial positions of the structural surface s ; and calculating the microconvex body characteristic parameter F of each microconvex body in the contact area by counting the height h and the corresponding microconvex body inclination angle θ of each microconvex body in the contact area, Based on the contact area A s , the wall surface strength of the structural plane JCS, and the normal stress F applied when performing the photoelastic test n and the micro-asperity characteristic parameter F define the shear failure evaluation parameter T of each micro-asperity, where σ n is the normal stress borne by each microconvexity; The shear damage evaluation parameter T is compared with the critical shear damage evaluation parameter T cr A size comparison is made to determine whether plastic deformation of the micro asperities occurs when T > T cr When T > T where F θ* is a critical microconvexity feature parameter, θ * is a critical inclination angle; The deformation height Δh of the micro asperity after plastic deformation under shear at a certain moment is calculated, wherein P is the normal stress σ borne by the micro asperity n and the resultant of the shear stress τ corresponding to the micro asperity; r b is the contact radius of the micro asperity with the base of the structural plane, E is the equivalent elastic modulus of the contact of the upper and lower modules of the structural plane, and r is the contact range of the micro asperity with the base of the structural plane. The micro asperity characteristic parameter F1 corresponding to each micro asperity after plastic deformation under shear is calculated, θ1=θ-Δθ h1=h-Δh Wherein Δθ is the angle changed by the micro asperity due to plastic deformation, l is the horizontal length of the micro asperity, h1 is the height of the micro asperity after plastic deformation, and θ1 is the inclination angle of the micro asperity after plastic deformation; The roughness evaluation parameter M of the structural plane after plastic deformation under shear is calculated, Wherein L is the length of the profile line extracted along the length direction of the replication model, all the extracted profile line lengths are set as L, n is the number of profile lines on the two-dimensional profile of the structural plane, m is the number of corresponding micro asperities on each profile line, and Fst represents the micro asperity characteristic parameter of the tth profile line s th micro asperity. Wherein 0<M<1, M represents the overall roughness of the structural plane, the greater the value of M, the greater the roughness of the structural plane, and the smaller the value of M, the smaller the roughness of the structural plane.

2. The simulation method of claim 1, wherein, The test device comprises an optical measurement system and a loading system for loading the replication model; The optical measurement system comprises a laser, a beam expander, a polarizer, a first 1 / 4 wave plate, a second 1 / 4 wave plate, an analyzer and a CCD camera arranged in sequence on a straight light path; The loading system located on the same straight light path as the optical measurement system is arranged between the first 1 / 4 wave plate and the second 1 / 4 wave plate to ensure that the laser light source transmits through the replication model, the loading system comprises a box body having a placing space, a circular ring-shaped pressurizing cylinder connected to the top plate of the box body and movable up and down relative to the box body, a support cylinder connected to the bottom plate of the box body and opposite to the pressurizing cylinder, a lower shear box for supporting the replication model and detachably lapped on the support cylinder, an upper shear box for pressing downward on the replication model and a horizontal force applying device for horizontally shearing the replication model; Wherein the pressurizing cylinder and the support cylinder both have holes in the interiors for the laser light source to pass through.

3. The simulation method of claim 2, wherein, The lower shear box is an L-shaped structure with a right block protruding upward at the right end, and the upper shear box is a door-shaped structure with an inner wall surface capable of closely abutting the replication module and a left block protruding downward at the left end; The horizontal force applying device comprises a loading head mechanism connected to the left side plate of the box body and horizontally movable relative to the box body, and a limiting mechanism connected to the right side plate of the box body and used for abutting against the right block. In the photoelastic test, the right block abuts against the lower mold, the left block abuts against the upper mold, and the loading head mechanism horizontally pushes the left block.

4. The simulation method of claim 2, wherein, The pressurizing cylinder is screw-connected to the top plate of the box body via internal and external threads, and a handle for driving the pressurizing cylinder to rotate is horizontally arranged on the outer side wall of the pressurizing cylinder; and / or The upper and lower shear boxes are made of acrylic plates.

5. The simulation method of claim 3, wherein, The photoelastic test specifically comprises: The replica model is placed into the upper and lower shear boxes and installed in place; The pressurizing cylinder is rotated downward to realize normal loading on the replica model, so that the replica model enters a constant pressure state; the loading head mechanism is rotated to apply a certain shear force to the replica model, and the shear force loading is limited and cannot exceed the shear strength of the structural surface; The rotation angle of the polarizer and the analyzer is changed, and six phase-shifted photoelastic fringe images under different analyzer polarization angles are captured by the CCD camera.

6. The simulation method of claim 1, wherein, The replica model satisfying the mechanical parameter requirement is also prepared, specifically comprising: A rock sample of a natural rock mass containing a structural surface to be evaluated is collected, point cloud information of the structural surface morphology of the rock sample is obtained, a three-dimensional digital model of the structural surface is established, and the replica model is obtained by 3D printing according to the three-dimensional digital model of the structural surface; The same physical and mechanical test is carried out on the rock sample and the replica model, and the mechanical parameter values of the rock sample and the replica model are obtained respectively, and when the error between the mechanical parameter values of the rock sample and the replica model satisfies the preset condition, the replica model satisfying the mechanical parameter requirement is obtained.

7. The simulation method of claim 5, wherein, mechanical parameter value P of the rock mass sample T mechanical parameter value P of the replica model S mechanical parameter value P of the replica model T -P S ≤α*P T wherein -5%≤α≤5%.

8. The simulation method of claim 1, wherein, The denoising preprocessing is performed to obtain a second photoelastic fringe image, specifically comprising: A spatial domain kernel representing the Euclidean distance between a point (p, q) in the neighborhood and a center point (i, j), σs is the standard deviation of the function; A value domain kernel representing the absolute value of the difference between the gray value f(p, q) of a point (p, q) in the neighborhood and the gray value f(i, j) of the center point (i, j), σr is the standard deviation of the function; The weight coefficient is the product w of the spatial domain kernel and the value domain kernel, w(i,j,p,q) = G σs (i,j,p,q)*G σr (i,j,p,q) Based on the weighted combination of the gray value f and its weight w in the neighborhood, the new pixel value g of the center point in the neighborhood is obtained, All pixel points in the first photoelastic fringe image are traversed to obtain the second photoelastic fringe image.

9. The simulation method of claim 1, wherein, The shear stress τ of each microconvex body at different spatial positions of the structural surface is obtained, specifically referring to: The second photoelastic fringe image is unwrapped and processed based on the shear stress difference method and the six-step phase shift method to obtain the shear stress τ of each microconvex body at different spatial positions of the structural surface.

10. A simulation system for evaluating the roughness evolution of rock mass discontinuities, suitable for the simulation method according to one of claims 1 to 9, characterized in that, The simulation system comprises: A test device for performing a photoelastic test on a replica model satisfying a mechanical parameter requirement based on a pre-obtained natural rock mass containing a structural surface to be evaluated, wherein the replica model comprises an upper mold and a lower mold combined by an upper structural surface and a lower structural surface having different undulating topographies; the test device comprises: An optical measurement system comprising, in sequence, a laser, a beam expander, a polarizer, a first 1 / 4 wave plate, a second 1 / 4 wave plate, an analyzer, and a CCD camera arranged on a straight light path; A loading system for loading the replication model is arranged on the same straight light path as the optical measurement system, and is arranged between the first 1 / 4 wave plate and the second 1 / 4 wave plate to ensure that the laser light source transmits through the replication model, the loading system comprising a box body having a placing space, a circular ring-shaped pressurizing cylinder connected to the top plate of the box body and movable up and down relative to the box body, a supporting cylinder connected to the bottom plate of the box body and opposite to the pressurizing cylinder, a lower shear box for supporting the replication model and detachably lapped on the supporting cylinder, an upper shear box for pressing downward on the replication model, and a horizontal force applying device for horizontally shearing the replication model; wherein the pressurizing cylinder and the supporting cylinder each have a hole for the laser light source to pass through; and An electronic device comprising a processor and a memory for storing a computer program, the processor executing the computer program to implement the following steps: obtaining a first photoelastic fringe image of a structural surface in a replication model at different analysis mirror polarization angles of a test device; performing denoising preprocessing on the first photoelastic fringe image using a bilateral filtering method to obtain a second photoelastic fringe image; and obtaining shear stress τ of each micro asperity at different spatial positions of the structural surface based on the second photoelastic fringe image; determining the contact area A between the upper structural surface and the lower structural surface based on the shear stress of each microconvex body at different spatial positions of the structural surface s ; calculating the microconvex body characteristic parameter F of each microconvex body in the contact area by counting the height h and the corresponding microconvex body inclination angle θ of each microconvex body in the contact area, Based on the contact area A s , the structural plane wall surface strength JCS, and the normal stress F applied when performing the photoelastic test n and the micro asperity characteristic parameter F define the shear failure evaluation parameter T of each micro asperity, where σ n is the normal stress borne by each microconvexity; The shear damage evaluation parameter T is compared with the critical shear damage evaluation parameter T cr A size comparison is made to determine whether plastic deformation of the micro asperity has occurred. When T > T cr , it indicates that plastic deformation of the micro asperity has occurred. where F θ* is a critical microconvexity feature parameter, θ * is a critical inclination angle; calculating a deformation height Δh of the micro asperity after plastic deformation under shear at a certain moment, where P is the normal stress σ borne by the micro asperity n and the resultant of the shear stress τ corresponding to the micro asperity; r b is the contact radius of the micro asperity with the base of the structural plane, E is the equivalent elastic modulus of the contact of the upper and lower modules of the structural plane, and r is the contact range of the micro asperity with the base of the structural plane. calculating a micro asperity characteristic parameter F1 corresponding to each micro asperity after plastic deformation under shear, θ1 = θ - Δθ h1 = h - Δh where Δθ is the angle changed by the micro asperity due to plastic deformation, l is the horizontal length of the micro asperity, h1 is the height of the micro asperity after plastic deformation, and θ1 is the inclination angle of the micro asperity after plastic deformation; calculating a roughness evaluation parameter M of the structural surface after plastic deformation under shear, where L is the length of a profile line extracted along the length direction of the replication model, all the extracted profile line lengths are set as L, n is the number of profile lines on the two-dimensional profile of the structural surface, m is the number of corresponding micro asperities on each profile line, and Fst represents the tth profile line s th micro asperity characteristic parameter; where 0 < M < 1, M represents the overall roughness of the structural surface, the greater the value of M, the greater the roughness of the structural surface, and the smaller the value of M, the smaller the roughness of the structural surface.

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