Magnetic mortar three-dimensional pore analysis method based on magnetic field effect

Abstract

The invention belongs to the technical field of magnetic mortar, and particularly provides a magnetic mortar three-dimensional pore analysis method based on the action of a magnetic field, which comprises the following steps: preparing a magnetic mortar test block; scanning the magnetic mortar test block through a CT machine to obtain a BMG format of an original CT slice corresponding to the magnetic mortar test block; importing the CT slice into Amira software, and processing the CT slice through a related command in the Amira software to obtain a three-dimensional space distribution diagram of magnetic mortar pores or pore area and volume information of a certain section; the magnetic field is simulated through Comsol software; in Comsol software, analyzing the pore change of the magnetic mortar test block in different magnetic induction line intensity ranges of the same section along with the change of the magnetic induction line intensity; or analyzing the morphological change of the pores near the magnetic induction lines. The method can be used for researching pore area and volume change rules in different magnetic induction intensity ranges under the action of the magnetic field, and the influence of the magnetic field on the pores of the magnetic mortar can be more intuitively shown.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetic mortar, and in particular relates to a three-dimensional pore analysis method of magnetic mortar under the action of a magnetic field. Background Art

[0002] The impact of porosity on concrete properties is a crucial research topic in concrete materials science. First, porosity reduces concrete strength by reducing the available material in the concrete, thereby impacting its bearing capacity and compressive strength. Second, porosity increases concrete permeability, reduces its durability, and makes it more susceptible to chemical attack and freeze-thaw damage, thus shortening its service life. Furthermore, porosity affects concrete's compactness, reducing its impermeability and durability, further accelerating its deterioration rate. Furthermore, porosity affects concrete's deformation properties, making it more susceptible to shrinkage and deformation cracks, thus compromising the overall stability of the concrete structure. Finally, porosity increases the amount of raw materials used in concrete, leading to increased production costs and thus impacting the economic performance of concrete products. Future research could focus on the mechanisms of porosity formation and the relationship between concrete microstructure and properties. Furthermore, through optimizing mix proportions, adding admixtures, and improving construction techniques, concrete porosity could be reduced, thereby improving its compactness and durability, and reducing costs, thereby promoting the sustainable development of concrete materials. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a three-dimensional pore analysis method of magnetic mortar under the action of a magnetic field, and to study the change law of pore area and volume in different magnetic induction intensity ranges under the action of a magnetic field, so as to more intuitively show the influence of the magnetic field on the pores of the magnetic mortar.

[0004] To solve the above technical problems, the technical solution adopted by the present invention is: a three-dimensional pore analysis method of magnetic mortar under the action of a magnetic field, comprising the following steps: Step 1: prepare magnetic mortar, pour the magnetic mortar into a mold to make a magnetic mortar test block, place the prepared magnetic mortar test block on a permanent magnet for curing, and polish the surface of the magnetic mortar test block after reaching a corresponding curing cycle; Step 2: Scan the polished magnetic mortar specimen using a CT machine to obtain the BMG format of the original CT slice corresponding to the magnetic mortar specimen; Step 3: Import the CT slices into Amira software and process them using relevant commands in Amira software to obtain a three-dimensional spatial distribution map of the pores in the magnetic mortar or the pore area and volume information of a certain interval; Step 4: Simulate the magnetic field using Comsol software; Step 5: Take a certain cross section of the magnetic mortar specimen, extract the data on the change in magnetic induction line intensity of the cross section, and analyze the change in the number and shape of pores in the magnetic mortar specimen with different magnetic induction line intensity ranges of the same cross section as the magnetic induction line intensity changes.

[0005] In a preferred embodiment, in step 1, the magnetic mortar includes ordinary Portland cement, magnetic powder, epoxy resin, coupling agent, reactive diluent and water.

[0006] In a preferred embodiment, the water-cement ratio of the magnetic mortar is 0.35-0.55, the mass content of magnetic powder in ordinary Portland cement is 5%-25%, the mass content of epoxy resin in ordinary Portland cement is 1%-9%, the mass content of coupling agent in ordinary Portland cement is 0-0.6%, and the amount of active diluent is 0-0.6% of the mass of ordinary Portland cement.

[0007] In a preferred embodiment, in step 1, the magnetic mortar is prepared as follows: S101. First, pour ordinary Portland cement into a container, add fly ash, wherein the mass ratio of ordinary Portland cement to fly ash is 1:1 to 3:1, then add magnetic powder, and stir for 2 to 4 minutes; S102, add epoxy resin emulsion and stir for 1 to 2 minutes; S103, add curing agent, the ratio of epoxy resin emulsion to curing agent is 1:1~2:1, and stir for 1~2 minutes; S104, add active diluent and stir for 40-60 seconds; S105. Finally, add the coupling agent and stir for 60-80 seconds.

[0008] In the preferred embodiment, in step S101, the magnetic powder is micron-sized Fe3O 4。

[0009] In a preferred solution, in step 2, the magnetic mortar test block is scanned by a CT machine. In the CT slices, black represents pores and gray represents magnetic mortar.

[0010] In a preferred embodiment, in step 3, processing the CT slices by using relevant commands in the Amira software includes the following steps: S301, reconstruct the size using Voxel size in Amira software so that the CT slice size in the software corresponds to the specimen size, and then crop the slice using the Crop editor command; S302, performing threshold segmentation on the magnetic mortar CT slices using the Intensity Range command in the Interactive Thresholding in the Amira software, and rendering the pores of the CT slices; S303, quantitatively analyzing the volume and area of the pores through the Label Analysis command; S304, rendering the three-dimensional pores or the pores in a certain interval in space by using the Sieve Analysis command; S305. Obtain the three-dimensional spatial distribution diagram of the magnetic mortar pores or the pore area and volume information of a certain interval through the Volume Rendering command.

[0011] In a preferred solution, in step S302, the threshold value range of the magnetic mortar pores for threshold segmentation of the magnetic mortar CT slices is 0-110.

[0012] In a preferred embodiment, in step 4, simulating the magnetic field generated by the bar magnet using Comsol software includes the following steps: S401, select a three-dimensional space dimension and select a magnetic field in a physical field; S402. Create two cuboids of different sizes, the small cuboid representing the magnet and the large cuboid representing the external environment, with the magnet being placed in the external environment and centered. S403, select the material Air for the external environment and select the material N52 for the magnet; S404. Click Ampere's law to set the residual magnetic flux density and direction of the magnet. S405. Add a study on steady-state distribution, calculate and obtain the three-dimensional plot group, the plot group of a certain cross section, and the magnetic induction intensity distribution diagram.

[0013] In a preferred solution, in step 402, the size of the magnet is 5CM×5CM×3CM.

[0014] The present invention provides a three-dimensional pore analysis method for magnetic mortar under the action of a magnetic field, which has the following beneficial effects: 1. This paper proposes a three-dimensional pore analysis method for magnetic mortar under the influence of a magnetic field. This method studies the changes in pore area and volume under different magnetic induction intensity ranges. Using Amira 3D, CT slices of the magnetic mortar are reconstructed in 3D to reveal the true pores within the mortar. The correlation between pore distribution and the strength and impermeability of the magnetic mortar anchor is analyzed.

[0015] 2. Through non-destructive testing, CT images are obtained due to the differences in heat absorption properties of different materials, which enables three-dimensional visualization of the internal structure of the magnetic mortar under the action of a magnetic field. Amira software is used to process CT images of different cross-sections of the magnetic slurry anchor body to restore the true distribution shape and position of the three-dimensional pores.

[0016] 3. By analyzing the pore structure of the magnetic mortar under different magnetic induction intensity ranges under a bar magnet, the influence of the magnetic field on the pore morphology is revealed. By quantitatively analyzing the pore structure after three-dimensional reconstruction, the influence of the magnetic field on the pores of the magnetic mortar is intuitively demonstrated. Overall, it is shown that as the magnetic induction intensity increases, the pore size decreases and the number of pores decreases.

[0017] 4. The magnetic field can make the magnetic particles present a specific distribution or arrangement in the mortar, thereby showing the characteristics of the pores more clearly. By understanding the changes in the properties of the pores caused by the magnetic field and the reduction in the size and number of pores, the essence of the enhanced strength of the magnetic slurry anchor body is explained.

[0018] 5. Even though this method was developed for magnetic mortar, it has certain versatility and extensibility, and can be extended to the pore analysis of other similar materials. It can be combined with other analysis techniques to form a more comprehensive material microstructure analysis system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is a flow chart of the three-dimensional pore analysis method of magnetic mortar under the action of a magnetic field; Figure 2 This is the threshold segmentation map of CT slices under the action of magnetic field; Figure 3 is the three-dimensional pore distribution map under the action of magnetic field; Figure 4 is the three-dimensional distribution diagram of pores in a certain longitudinal interval under the action of magnetic field; Figure 5 is the spatial distribution diagram of the magnetic field intensity of the bar magnet; Figure 6 is the magnetic field intensity distribution diagram of the longitudinal section; Figure 7 It is a curve diagram of the change of magnetic induction intensity along the longitudinal direction of the bar magnet; Figure 8 It is the magnetic induction intensity diagram of the cross section corresponding to different longitudinal heights; Figure 9 The corresponding pore change diagrams for different longitudinal intervals; Figure 10 This is the pore map of the magnetic mortar in the interval under the action of magnetic field; Figure 11This is a graph showing the change of pore size with the intensity of magnetic flux lines. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] Example 1: like Figure 1 As shown, a three-dimensional pore analysis method of magnetic mortar under the action of a magnetic field includes the following steps: Step 1: prepare magnetic mortar, pour the magnetic mortar into a mold to make a magnetic mortar test block, place the prepared magnetic mortar test block on a permanent magnet for curing, and polish the surface of the magnetic mortar test block after reaching the corresponding curing cycle.

[0023] The water-cement ratio of the magnetic mortar is 0.44, the magnetic powder content is 20% (relative to the mass of ordinary Portland cement), the polymer-cement ratio is 6% (the mass of epoxy resin relative to ordinary Portland cement), the active diluent content is 0.2% (the mass of active diluent relative to ordinary Portland cement), and the coupling agent content is 0.2% (relative to the mass of ordinary Portland cement).

[0024] The specific operations are as follows: S101. First, pour ordinary Portland cement into a container, add fly ash, wherein the mass ratio of ordinary Portland cement to fly ash is 1:1 to 3:1, then add magnetic powder, and stir for 2 to 4 minutes; S102, add epoxy resin emulsion and stir for 1 to 2 minutes; S103, add curing agent, the ratio of epoxy resin emulsion to curing agent is 1:1~2:1, and stir for 1~2 minutes; S104, add active diluent and stir for 40-60 seconds; S105. Finally, add the coupling agent and stir for 60-80 seconds.

[0025] Step 2: Scan the polished magnetic mortar specimen using a CT machine to obtain the BMG format of the original CT slice corresponding to the magnetic mortar specimen.

[0026] In the CT slices, black represents pores and gray represents magnetic mortar.

[0027] Step 3: Import the CT slices into the Amira software and process the CT slices through the relevant commands in the Amira software to obtain the three-dimensional spatial distribution map of the magnetic mortar pores or the pore area and volume information of a certain interval.

[0028] The CT slices are processed using relevant commands in the Amira software, including the following steps: S301, reconstructing the size using the Voxel size in the software so that the CT slice size in the software corresponds to the test block size, and then cropping the slices using the Cropeditor command.

[0029] S302, such as Figure 2 In the software, the Intensity Range command in the Interactive Thresholding was used to perform threshold segmentation on the magnetic mortar CT slices, and the pores of the CT slices were rendered.

[0030] The threshold value of magnetic mortar porosity ranges from 0 to 110, and within this range it is indicated as magnetic mortar porosity, otherwise it is magnetic mortar.

[0031] S303. Quantitatively analyze the volume and area of the pores using the Label Analysis command.

[0032] S304, such as Figure 3 and 4 As shown in the figure, the Sieve Analysis command is used to render the three-dimensional pores in space or the pores in a certain interval.

[0033] S305. Obtain the three-dimensional spatial distribution diagram of the magnetic mortar pores or the pore area and volume information of a certain interval through the Volume Rendering command.

[0034] Step 4: Figure 5 As shown, the magnetic field is simulated by Comsol software.

[0035] The following steps are involved: S401, select a three-dimensional space dimension and select a magnetic field in a physical field; S402. Create two cuboids of different sizes, the small cuboid representing the magnet and the large cuboid representing the external environment, with the magnet being placed in the external environment and centered. S403, select the material Air for the external environment and select the material N52 for the magnet; S404. Click Ampere's law to set the residual magnetic flux direction of the magnet. S405. Add a study on steady-state distribution, calculate and obtain the three-dimensional plot group, the plot group of a certain cross section, and the magnetic induction intensity distribution diagram.

[0036] Step 5: Take a longitudinal section of the magnetic mortar specimen, extract the data on the change in magnetic induction line intensity of the section, and analyze the change in the number and shape of pores in the magnetic mortar specimen with different magnetic induction line intensity ranges on the same section as the magnetic induction line intensity changes.

[0037] Select three longitudinal sections, such as Figure 6 For the spatial magnetic field, select the X coordinate 1MM as section 1, 20MM as section 2, and 39MM as section 3, and the corresponding axial magnetic field intensity change diagram.

[0038] According to the analysis of the different magnetic induction line intensity ranges of sections 1, 2, and 3, the porosity changes of the magnetic mortar specimens as the magnetic induction line intensity changes are shown in Tables 1 to 3.

[0039]

[0040]

[0041]

[0042] Example 2: like Figure 1 As shown, a three-dimensional pore analysis method of magnetic mortar under the action of a magnetic field includes the following steps: Step 1: prepare magnetic mortar, pour the magnetic mortar into a mold to make a magnetic mortar test block, place the prepared magnetic mortar test block on a permanent magnet for curing, and polish the surface of the magnetic mortar test block after reaching the corresponding curing cycle.

[0043] The water-cement ratio in the magnetic mortar is 0.4, the magnetic powder content is 20% (relative to the mass of cement), the polymer-cement ratio is 6% (the mass of epoxy resin relative to cement), the active diluent content is 0.2% (the mass of active diluent relative to cement), and the coupling agent content is 0.2% (relative to the mass of cement). The steps for preparing the magnetic mortar are as follows: S101. First, pour ordinary Portland cement into a container, add fly ash, wherein the mass ratio of ordinary Portland cement to fly ash is 1:1 to 3:1, then add magnetic powder, and stir for 2 to 4 minutes; S102, add epoxy resin emulsion and stir for 1 to 2 minutes; S103, add curing agent, the ratio of epoxy resin emulsion to curing agent is 1:1~2:1, and stir for 1~2 minutes; S104, add active diluent and stir for 40-60 seconds; S105. Finally, add the coupling agent and stir for 60-80 seconds.

[0044] Step 2: Scan the polished magnetic mortar specimen using a CT machine to obtain the BMG format of the original CT slice corresponding to the magnetic mortar specimen.

[0045] In the CT slices, black represents pores and gray represents magnetic mortar.

[0046] Step 3: Import the CT slices into the Amira software and process the CT slices through the relevant commands in the Amira software to obtain the three-dimensional spatial distribution map of the magnetic mortar pores or the pore area and volume information of a certain interval.

[0047] The CT slices are processed using the relevant commands in the Amira software, including the following steps: S301. Reconstruct the size using the Voxel size in the software so that the CT slice size in the software corresponds to the specimen size, and then crop the slice using the Crop editor command.

[0048] S302, such as Figure 2 In the software, the Intensity Range command in the Interactive Thresholding was used to perform threshold segmentation on the magnetic mortar CT slices, and the pores of the CT slices were rendered.

[0049] S303. Quantitatively analyze the volume and area of the pores using the Label Analysis command.

[0050] S304, such as Figure 3 and 4 As shown in the figure, the Sieve Analysis command is used to render the three-dimensional pores in space or the pores in a certain interval.

[0051] S305. Obtain the three-dimensional spatial distribution diagram of the magnetic mortar pores or the pore area and volume information of a certain interval through the Volume Rendering command.

[0052] Step 4: Figure 5 As shown in the figure, the magnetic field generated by the bar magnet is simulated using Comsol software.

[0053] The following steps are involved: S401, select a three-dimensional space dimension and select a magnetic field in a physical field; S402. Create two cuboids of different sizes. The small cuboid represents the magnet, and the large cuboid represents the external environment. The magnet is placed in the external environment and centered. The dimensions of the magnet are 5 cm x 5 cm x 3 cm, i.e., the dimensions of the small cuboid. S403, select the material Air for the external environment and select the material N52 for the magnet; S404. Click Ampere's law to set the residual magnetic flux direction of the magnet. S405. Add a study on steady-state distribution, calculate and obtain the three-dimensional plot group, the plot group of a certain cross section, and the magnetic induction intensity distribution diagram.

[0054] Step 5: Take the transverse cross section of the magnetic slurry anchor body, extract the data of the change of magnetic induction line intensity of the cross section, and analyze the number and morphology of pores in the magnetic mortar specimens with different magnetic induction line intensity ranges in the same cross section as the magnetic induction line intensity changes.

[0055] Four sections are selected along different heights, 10MM is section 4, 20MM is section 5, 30MM is section 6, and 40MM is section 7, corresponding to the axial magnetic field intensity change diagram.

[0056] According to the analysis of sections 4, 5, 6 and 7, the porosity changes of magnetic mortar specimens change with the intensity of magnetic induction lines as shown in Table 4.

[0057]

[0058] Example 3: like Figure 1 As shown, a three-dimensional pore analysis method of magnetic mortar under the action of a magnetic field includes the following steps: Step 1: prepare magnetic mortar, pour the magnetic mortar into a mold to make a magnetic mortar test block, place the prepared magnetic mortar test block on a permanent magnet for curing, and polish the surface of the magnetic mortar test block after reaching the corresponding curing cycle.

[0059] The water-cement ratio in the magnetic mortar is 0.4, the magnetic powder content is 20% (relative to the mass of cement), the polymer-cement ratio is 6% (the mass of epoxy resin relative to cement), the active diluent content is 0.2% (the mass of active diluent relative to cement), and the coupling agent content is 0.2% (relative to the mass of cement). The steps for preparing the magnetic mortar are as follows: S101. First, pour ordinary Portland cement into a container, add fly ash, wherein the mass ratio of ordinary Portland cement to fly ash is 1:1 to 3:1, then add magnetic powder, and stir for 2 to 4 minutes; S102, add epoxy resin emulsion and stir for 1 to 2 minutes; S103, add curing agent, the ratio of epoxy resin emulsion to curing agent is 1:1~2:1, and stir for 1~2 minutes; S104, add active diluent and stir for 40-60 seconds; S105. Finally, add the coupling agent and stir for 60-80 seconds.

[0060] Step 2: Scan the polished magnetic mortar specimen using a CT machine to obtain the BMG format of the original CT slice corresponding to the magnetic mortar specimen.

[0061] In the CT slices, black represents pores and gray represents magnetic mortar. To make the pores more obvious, the black represents pores and turns red, e.g. Figure 2 .

[0062] Step 3: Import the CT slices into the Amira software and process the CT slices through the relevant commands in the Amira software to obtain the three-dimensional spatial distribution map of the magnetic mortar pores or the pore area and volume information of a certain interval.

[0063] The CT slices are processed using the relevant commands in the Amira software, including the following steps: S301. Reconstruct the size using the Voxel size in the software so that the CT slice size in the software corresponds to the specimen size, and then crop the slice using the Crop editor command.

[0064] S302, such as Figure 2 In the software, the Intensity Range command in the Interactive Thresholding was used to perform threshold segmentation on the magnetic mortar CT slices, and the pores of the CT slices were rendered.

[0065] S303. Quantitatively analyze the volume and area of the pores using the Label Analysis command.

[0066] S304, such as Figure 3 and 4 As shown in the figure, the Sieve Analysis command is used to render the three-dimensional pores in space or the pores in a certain interval.

[0067] S305. Obtain the three-dimensional spatial distribution diagram of the magnetic mortar pores or the pore area and volume information of a certain interval through the Volume Rendering command.

[0068] Step 4: Figure 5 As shown in the figure, the magnetic field of the bar magnet is simulated by Comsol software.

[0069] The operation in Comsol software includes the following steps: S401, select a three-dimensional space dimension and select a magnetic field in a physical field; S402. Create two cuboids of different sizes, the small cuboid representing the magnet and the large cuboid representing the external environment, with the magnet being placed in the external environment and centered. S403, select the material Air for the external environment and select the material N52 for the magnet; S404. Click Ampere's law to set the residual magnetic flux direction of the magnet. S405, add the study of steady-state distribution, calculate the three-dimensional drawing group and a cross-section drawing group and magnetic induction intensity distribution diagram, the magnetic induction line distribution is as follows Figure 6, the cross-section changes along the height of the magnetic induction intensity as follows Figure 7 , the magnetic induction intensity value of a certain longitudinal section changes along the height as follows Figure 8 .

[0070] Step 5: Take a longitudinal section of the magnetic slurry anchor body, extract the data of the change in magnetic induction line intensity of the section, and analyze the number and shape of pores in the magnetic mortar specimens with different magnetic induction line intensity ranges in the same section as the magnetic induction line intensity changes.

[0071] like Figure 9 As shown in Figure 2, the three-dimensional pore morphology changes from circular to flat as the intensity of the magnetic field induction line changes, and the size of the pores also decreases continuously; Figure 10 As shown in the longitudinal section of the magnetic slurry anchor body, the relationship between the pore distribution and the magnetic flux line distribution is that the magnetic flux lines are densely distributed in the lower part, and the pore size and number are small; Figure 11 As shown, the pores are distributed along the magnetic induction lines, and the pore shape is an irregular ellipsoid.

[0072] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A three-dimensional pore analysis method of magnetic mortar under the action of a magnetic field, characterized in that: The following steps are involved: Step 1: prepare magnetic mortar, pour the magnetic mortar into a mold to make a magnetic mortar test block, place the prepared magnetic mortar test block on a permanent magnet for curing, and polish the surface of the magnetic mortar test block after reaching a corresponding curing cycle; Step 2: Scan the polished magnetic mortar specimen using a CT machine to obtain the BMG format of the original CT slice corresponding to the magnetic mortar specimen; Step 3: Import the CT slices into Amira software and process them using relevant commands in Amira software to obtain a three-dimensional spatial distribution map of the pores in the magnetic mortar or the pore area and volume information of a certain interval; Step 4: Simulate the magnetic field using Comsol software; Step 5: Take a certain cross section of the magnetic mortar specimen, extract the data on the change in magnetic induction line intensity of the cross section, and analyze the change in the number and shape of pores in the magnetic mortar specimen with different magnetic induction line intensity ranges of the same cross section as the magnetic induction line intensity changes.

2. The method for three-dimensional pore analysis of magnetic mortar under magnetic field according to claim 1 is characterized in that: In the step 1, the magnetic mortar includes ordinary Portland cement, magnetic powder, epoxy resin, coupling agent, active diluent and water.

3. The method for three-dimensional pore analysis of magnetic mortar under magnetic field according to claim 2, characterized in that: The water-cement ratio of the magnetic mortar is 0.35-0.55, the mass content of magnetic powder in ordinary Portland cement is 5%-25%, the mass content of epoxy resin in ordinary Portland cement is 1%-9%, the mass content of coupling agent in ordinary Portland cement is 0-0.6%, and the active diluent content is 0-0.6% of the mass of ordinary Portland cement.

4. The method for three-dimensional pore analysis of magnetic mortar under magnetic field according to claim 3 is characterized in that: In the step 1, the magnetic mortar is prepared as follows: S101. First, pour ordinary Portland cement into a container, add fly ash, wherein the mass ratio of ordinary Portland cement to fly ash is 1:1 to 3:1, then add magnetic powder, and stir for 2 to 4 minutes; S102, add epoxy resin emulsion and stir for 1 to 2 minutes; S103, add curing agent, the ratio of epoxy resin emulsion to curing agent is 1:1~2:1, and stir for 1~2 minutes; S104, add active diluent and stir for 40-60 seconds; S105. Finally, add the coupling agent and stir for 60-80 seconds.

5. The method for three-dimensional pore analysis of magnetic mortar under magnetic field according to claim 4 is characterized in that: In step S101, the magnetic powder is micron-sized Fe3O 4。 6. The method for three-dimensional pore analysis of magnetic mortar under magnetic field according to claim 1, characterized in that: In the second step, the magnetic mortar test block is scanned by a CT machine. In the CT slices, black represents pores and gray represents magnetic mortar.

7. The method for three-dimensional pore analysis of magnetic mortar under magnetic field according to claim 1, characterized in that: In the step 3, the CT slices are processed by the relevant commands in the Amira software, including the following steps: S301, reconstruct the size using Voxel size in Amira software so that the CT slice size in the software corresponds to the specimen size, and then crop the slice using the Crop editor command; S302, performing threshold segmentation on the magnetic mortar CT slices using the Intensity Range command in the Interactive Thresholding in the Amira software, and rendering the pores of the CT slices; S303, quantitatively analyzing the volume and area of the pores through the Label Analysis command; S304, rendering the three-dimensional pores or the pores in a certain interval in space by using the Sieve Analysis command; S305. Obtain the three-dimensional spatial distribution diagram of the magnetic mortar pores or the pore area and volume information of a certain interval through the Volume Rendering command.

8. The method for three-dimensional pore analysis of magnetic mortar under magnetic field according to claim 7, characterized in that: In step S302, the threshold value range of the magnetic mortar pores for threshold segmentation of the magnetic mortar CT slice is 0-110.

9. The method for three-dimensional pore analysis of magnetic mortar under magnetic field according to claim 1, characterized in that: In the fourth step, simulating the magnetic field generated by the bar magnet using Comsol software includes the following steps: S401, select a three-dimensional space dimension and select a magnetic field in a physical field; S402. Create two cuboids of different sizes, the small cuboid representing the magnet and the large cuboid representing the external environment, with the magnet being placed in the external environment and centered. S403, select the material Air for the external environment and select the material N52 for the magnet; S404. Click Ampere's law to set the residual magnetic flux density and direction of the magnet. S405. Add a study on steady-state distribution, calculate and obtain the three-dimensional drawing group, the drawing group of a certain cross section, and the magnetic induction intensity distribution diagram.

10. The method for three-dimensional pore analysis of magnetic mortar under magnetic field according to claim 9, characterized in that: In step 402, the size of the magnet is 5CM×5CM×3CM.

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