EPS concrete three-dimensional numerical test piece reconstruction method and system based on CT scanning

Abstract

The invention discloses an EPS concrete three-dimensional numerical value test piece reconstruction method and system based on CT scanning, and relates to the technical field of lightweight concrete.The method comprises the steps that CT scanning is conducted on a to-be-tested EPS concrete test piece, and an internal structure slice image of the to-be-tested EPS concrete test piece is obtained; based on a digital image processing technology, identifying structural features and characterization of the internal structure slice image; constructing a three-dimensional numerical model of the to-be-tested EPS concrete test piece based on the structural features and characterization of the internal structure slice image; and based on the three-dimensional numerical model, carrying out numerical simulation on the loaded fracture process of the to-be-tested EPS concrete test piece. The technical problem that various characteristics of the EPS concrete cannot be truly reflected in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of lightweight concrete, and in particular to a method and system for reconstructing a three-dimensional numerical specimen of EPS concrete based on CT scanning. Background Art

[0002] Concrete is one of the most widely used building materials in modern engineering construction, but due to its heavy weight and poor crack resistance, it has certain limitations in application. EPS is the abbreviation of Expanded Polystyrene. EPS concrete is made by adding EPS particles as lightweight aggregate into concrete. According to the different dosages, lightweight concrete with different apparent densities is prepared. Because it effectively utilizes the excellent physical properties of polystyrene foam such as light weight, sound insulation, heat preservation, and heat insulation, and makes a large amount of waste polystyrene foam available for secondary use, it can largely solve the more serious pollution problems in society at this stage, save energy and protect the environment, and thus has been widely valued by professional scholars at home and abroad. However, EPS concrete materials themselves also have certain defects. How to improve the deficiencies and effectively utilize its excellent properties is the main direction of current research, so that EPS concrete can play a greater role in practical applications.

[0003] Depending on the content and size of EPS particles, EPS concrete will show different apparent densities and properties: when the material density is high, EPS concrete will show brittle material characteristics; when the material density is low, it will show foam energy-absorbing material characteristics. Therefore, when studying the static compression and splitting characteristics of EPS concrete, it is necessary to construct the EPS concrete stress and density model and the stress-strain relationship model. The density model and the stress-strain relationship model can fit more scientific experimental results.

[0004] Summarizing the existing data, it is found that domestic and foreign scholars have conducted more research on the size effect of ordinary concrete, and most of them are based on experiments, while there are relatively few studies on the particle size effect of EPS concrete. Due to the limitations of experimental conditions and observation methods, experimental research has certain difficulties. It is not only time-consuming and laborious, but the experimental results cannot truly reflect the various characteristics of EPS concrete due to differences in the environment, conditions and itself. Summary of the invention

[0005] In order to solve the above technical problems existing in the prior art, the embodiment of the present invention provides a method and system for reconstructing a three-dimensional numerical specimen of EPS concrete based on CT scanning. The technical solution is as follows:

[0006] On the one hand, a method for reconstructing a three-dimensional numerical specimen of EPS concrete based on CT scanning is provided, the method comprising: performing a CT scan on the EPS concrete specimen to be tested to obtain an internal structure slice image of the EPS concrete specimen to be tested; based on digital image processing technology, identifying the structural features and representations of the internal structure slice image; based on the structural features and representations of the internal structure slice image, constructing a three-dimensional numerical model of the EPS concrete specimen to be tested; based on the three-dimensional numerical model, performing a numerical simulation of the load-bearing fracture process of the EPS concrete specimen to be tested.

[0007] Furthermore, based on digital image processing technology, the structural features and representations of the internal structure slice image are identified, including: cropping, median filtering and binarization of the internal structure slice image to obtain a preprocessed image; importing the preprocessed image into a rock fracture process analysis system, and using digital image processing technology to analyze the structural features and representations.

[0008] Furthermore, the structural features include various types of mesoscopic media; and the characterization includes color features.

[0009] Furthermore, based on the structural features and characterization of the internal structure slice image, a three-dimensional numerical model of the EPS concrete specimen to be tested is constructed, including: constructing a three-dimensional numerical network based on the internal structure slice image and the finite element method; assigning materials to the three-dimensional numerical network based on the structural features and characterization to construct the three-dimensional numerical model.

[0010] Furthermore, based on the three-dimensional numerical model, a numerical simulation of the load-bearing fracture process of the EPS concrete specimen to be tested is performed, including: inputting control parameter values ​​of each mesoscopic medium constitutive equation based on the three-dimensional numerical model, setting boundary conditions, and analyzing the material mechanical behavior and failure process under external loads.

[0011] On the other hand, a CT scanning-based EPS concrete three-dimensional numerical specimen reconstruction system is also provided, comprising: a scanning module, an identification module, a construction module and a simulation module; wherein the scanning module is used to perform CT scanning on the EPS concrete specimen to be tested to obtain an internal structure slice image of the EPS concrete specimen to be tested; the identification module is used to identify the structural features and representations of the internal structure slice image based on digital image processing technology; the construction module is used to construct a three-dimensional numerical model of the EPS concrete specimen to be tested based on the structural features and representations of the internal structure slice image; the simulation module is used to perform a numerical simulation of the load-bearing fracture process of the EPS concrete specimen to be tested based on the three-dimensional numerical model.

[0012] Furthermore, the recognition module is also used to: perform cropping, median filtering and binarization on the internal structure slice image to obtain a preprocessed image; import the preprocessed image into the rock fracture process analysis system, and use digital image processing technology to analyze the structural characteristics and representations.

[0013] Furthermore, the construction module is also used to: construct a three-dimensional numerical network based on the internal structure slice image and the finite element method; assign materials to the three-dimensional numerical network based on the structural characteristics and characterization to construct the three-dimensional numerical model.

[0014] On the other hand, an electronic device is provided, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method described in the first aspect when executing the computer program.

[0015] On the other hand, a computer-readable storage medium is provided, in which a program code is stored. The program code can be called by a processor to execute the method described in the first aspect.

[0016] The embodiment of the present invention provides a method and system for reconstructing a three-dimensional numerical specimen of EPS concrete based on CT scanning, establishes a micromechanical model of EPS concrete based on random distribution, simulates the damage and failure process of EPS concrete under quasi-static load, and analyzes the damage and failure process of EPS concrete, thereby providing a feasible method for in-depth research on the mechanical response of composite concrete materials, etc., and alleviating the technical problem that the prior art cannot truly reflect the various characteristics of EPS concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 It is a flow chart of a method for reconstructing a three-dimensional numerical specimen of EPS concrete based on CT scanning provided by an embodiment of the present invention;

[0019] Figure 2 is a schematic diagram of an internal structure slice image of an EPS concrete specimen to be tested provided by an embodiment of the present invention;

[0020] Figure 3 is a schematic diagram of a three-dimensional numerical model provided by an embodiment of the present invention;

[0021] Figure 4 It is a schematic diagram of a CT scanning-based EPS concrete three-dimensional numerical specimen reconstruction system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0023] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either of the two.

[0024] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0025] Embodiment 1

[0026] Figure 1 FIG. 1 is a flow chart of a method for reconstructing a three-dimensional numerical specimen of EPS concrete based on CT scanning according to an embodiment of the present invention. Figure 1 As shown, the method specifically comprises the following steps:

[0027] Step S102: Perform CT scanning on the EPS concrete specimen to be tested to obtain an internal structure slice image of the EPS concrete specimen to be tested.

[0028] Figure 2 FIG. 1 is a schematic diagram of an internal structure slice image of an EPS concrete specimen to be tested according to an embodiment of the present invention. Figure 2 As shown in the figure, the internal structure of the sample can be observed intuitively through the internal structure slice image, and cracks, minerals, matrix, etc. can be clearly distinguished according to the different grayscale values ​​of the image.

[0029] Step S104: identifying the structural features and representations of the internal structure slice images based on digital image processing technology.

[0030] Step S106, constructing a three-dimensional numerical model of the EPS concrete specimen to be tested based on the structural features and representations of the internal structure slice images.

[0031] Step S108: Based on the three-dimensional numerical model, a numerical simulation of the load-bearing fracture process of the EPS concrete specimen to be tested is performed.

[0032] Specifically, step S104 also includes the following steps:

[0033] Step S1041, performing clipping, median filtering and binarization processing on the internal structure slice image to obtain a pre-processed image;

[0034] Step S1042, importing the pre-processed image into the rock fracture process analysis system, and using digital image processing technology to analyze the structural characteristics and representations.

[0035] Specifically, the Rock Failure Process Analysis System (RFPA) is a rock failure process analysis system that uses elastic mechanics as a stress analysis tool and elastic damage theory and its modified Coulomb failure criterion as a medium deformation and failure analysis module.

[0036] Specifically, the structural characteristics include various types of mesoscopic media; the characterization includes color characteristics.

[0037] In the embodiment of the present invention, digital image processing technology is used to analyze the color characteristics of the image, identify various types of meso-media, that is, determine the material ID of the meso-media, and determine the material area of ​​the meso-media.

[0038] Specifically, step S106 also includes the following steps:

[0039] Step S1061, constructing a three-dimensional numerical network based on the internal structure slice image and the finite element method.

[0040] Step S1062 , assigning materials to the three-dimensional numerical network based on the structural features and representations, and constructing a three-dimensional numerical model.

[0041] Figure 3 is a schematic diagram of a three-dimensional numerical model provided according to an embodiment of the present invention.

[0042] Specifically, a three-dimensional numerical network is first constructed using CT sections. In the finite element method, the concrete specimen needs to be divided into many small grids. Since the digital image is composed of pixels arranged in a rectangle, each pixel can be regarded as a unit in the finite element grid. For each pixel, the coordinates of its four corner points can be converted into the physical positions of the corresponding vector space, and the node coordinates can be obtained by transforming the actual size of the image with the pixel size of the image.

[0043] Then, the RFPA software automatically converts the processed non-uniform characterization image into a finite element mesh, and uses the software's quick and convenient material assignment function to assign values ​​to the mesoscopic dielectric material, thereby establishing a numerical model that can reflect the material's mesoscopic structure. The entire image can be converted into a square finite element mesh, and the corresponding material type can be assigned in the numerical calculation according to the color category of each pixel point, so that the non-uniformity of concrete can be considered in the calculation. The square unit mapping method is mainly used in RFPA. The use of consistent square grid units can eliminate the grid effect in the crack propagation process to a certain extent; however, the bitmap vectorization method can also be used to establish a grid model through the finite element grid automatic generation program and import it into RFPA for calculation.

[0044] Specifically, step S108 also includes the following steps: inputting control parameter values ​​of each mesoscopic medium constitutive equation based on the three-dimensional numerical model, setting boundary conditions, and analyzing the mechanical behavior and failure process of the material under the action of external loads.

[0045] From the above description, it can be seen that the embodiment of the present invention provides a method for reconstructing three-dimensional numerical specimens of EPS concrete based on CT scanning, establishes a micromechanical model of EPS concrete based on random distribution, simulates the damage and failure process of EPS concrete under quasi-static load, and analyzes the damage and failure process of EPS concrete, which provides a feasible method for in-depth research on the mechanical response of composite concrete materials, etc., and alleviates the technical problem that the prior art cannot truly reflect the various characteristics of EPS concrete.

[0046] Embodiment 2

[0047] Figure 4 FIG. 1 is a schematic diagram of a CT scanning-based EPS concrete three-dimensional numerical specimen reconstruction system according to an embodiment of the present invention. Figure 4 As shown, the system includes: a scanning module 10, a recognition module 20, a construction module 30 and a simulation module 40.

[0048] Specifically, the scanning module 10 is used to perform CT scanning on the EPS concrete specimen to be tested to obtain an internal structure slice image of the EPS concrete specimen to be tested;

[0049] The recognition module 20 is used to recognize the structural features and representations of the internal structure slice image based on digital image processing technology;

[0050] A construction module 30 is used to construct a three-dimensional numerical model of the EPS concrete specimen to be tested based on the structural features and representations of the internal structure slice images;

[0051] The simulation module 40 is used to perform numerical simulation of the load-bearing fracture process of the EPS concrete specimen to be tested based on the three-dimensional numerical model.

[0052] Specifically, the identification module 20 is further used for:

[0053] The internal structure slice image is clipped, median filtered and binarized to obtain the pre-processed image;

[0054] The pre-processed images are imported into the rock fracture process analysis system, and the structural characteristics and representations are analyzed using digital image processing technology.

[0055] Specifically, the building block 30 is further used for:

[0056] Construct a three-dimensional numerical network based on internal structure slice images and finite element method;

[0057] The three-dimensional numerical network is assigned materials based on structural features and characterization to construct a three-dimensional numerical model.

[0058] Specifically, the simulation module 40 is also used to: input the control parameter values ​​of each mesoscopic medium constitutive equation based on the three-dimensional numerical model, set boundary conditions, and analyze the mechanical behavior and failure process of the material under the action of external loads.

[0059] The present invention further provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method in the above-mentioned embodiment 1 when executing the computer program.

[0060] The present invention further provides a computer-readable storage medium, in which program codes are stored. The program codes can be called by a processor to execute the method in the above-mentioned embodiment 1.

[0061] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0062] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0063] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described equipment, devices and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0064] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0065] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0066] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for reconstructing three-dimensional numerical specimens of EPS concrete based on CT scanning, characterized in that: The method comprises: Performing CT scanning on the EPS concrete specimen to be tested to obtain an internal structure slice image of the EPS concrete specimen to be tested; Based on digital image processing technology, identifying structural features and representations of the internal structure slice image; Based on the structural features and representations of the internal structure slice images, a three-dimensional numerical model of the EPS concrete specimen to be tested is constructed; Based on the three-dimensional numerical model, a numerical simulation of the load-bearing fracture process of the EPS concrete specimen to be tested is performed.

2. The method according to claim 1, characterized in that Based on digital image processing technology, the structural features and representations of the internal structure slice images are identified, including: Performing clipping, median filtering and binarization processing on the internal structure slice image to obtain a pre-processed image; The pre-processed image is imported into a rock fracture process analysis system, and the structural features and representations are analyzed using digital image processing technology.

3. The method according to claim 1 or 2, characterized in that: The structural features include various types of microscopic media; the characterization includes color features.

4. The method according to claim 1, characterized in that: Based on the structural features and representations of the internal structure slice image, a three-dimensional numerical model of the EPS concrete specimen to be tested is constructed, including: constructing a three-dimensional numerical network based on the internal structure slice image and the finite element method; The three-dimensional numerical network is assigned materials based on the structural features and representations to construct the three-dimensional numerical model.

5. The method according to claim 1, characterized in that Based on the three-dimensional numerical model, a numerical simulation of the load-breaking process of the EPS concrete specimen to be tested is performed, including: Based on the three-dimensional numerical model, the control parameter values ​​of each mesoscopic medium constitutive equation are input, boundary conditions are set, and the mechanical behavior and failure process of the material under the action of external loads are analyzed.

6. A CT scanning-based EPS concrete three-dimensional numerical specimen reconstruction system, characterized in that: include: scanning module, recognition module, construction module and simulation module; among them, The scanning module is used to perform CT scanning on the EPS concrete specimen to be tested to obtain an internal structure slice image of the EPS concrete specimen to be tested; The recognition module is used to recognize the structural features and representations of the internal structure slice image based on digital image processing technology; The construction module is used to construct a three-dimensional numerical model of the EPS concrete specimen to be tested based on the structural features and representations of the internal structure slice image; The simulation module is used to perform numerical simulation of the load-bearing fracture process of the EPS concrete specimen to be tested based on the three-dimensional numerical model.

7. The system according to claim 6, characterized in that The identification module is further used for: Performing clipping, median filtering and binarization processing on the internal structure slice image to obtain a pre-processed image; The pre-processed image is imported into a rock fracture process analysis system, and the structural features and representations are analyzed using digital image processing technology.

8. The system according to claim 6, characterized in that The building blocks are also used to: constructing a three-dimensional numerical network based on the internal structure slice image and the finite element method; The three-dimensional numerical network is assigned materials based on the structural features and representations to construct the three-dimensional numerical model.

9. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method according to any one of claims 1 to 5 when executing the computer program.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program codes, which can be called by a processor to execute the method according to any one of claims 1 to 5.

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