CN116844679B - Numerical simulation method for angle die compression shear experiment - Google Patents
Numerical simulation method for angle die compression shear experiment Download PDFInfo
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- 230000006835 compression Effects 0.000 title claims abstract description 38
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- 238000000034 method Methods 0.000 title claims abstract description 37
- 238000004088 simulation Methods 0.000 title claims abstract description 35
- 238000010008 shearing Methods 0.000 claims abstract description 69
- 238000007723 die pressing method Methods 0.000 claims abstract description 52
- 238000006073 displacement reaction Methods 0.000 claims abstract description 34
- 239000000463 material Substances 0.000 claims abstract description 32
- 238000012544 monitoring process Methods 0.000 claims abstract description 16
- 238000003825 pressing Methods 0.000 claims abstract description 16
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- 238000005498 polishing Methods 0.000 abstract description 2
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- 239000011435 rock Substances 0.000 description 4
- 238000013461 design Methods 0.000 description 3
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- 230000002238 attenuated effect Effects 0.000 description 1
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- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
- G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces
Abstract
The application belongs to the field of geotechnical engineering numerical simulation, and particularly relates to a numerical simulation method for an angle modeling compression shear experiment. Drawing an angle mould pressing and shearing mould in AutoCAD, introducing FLAC3D, and generating an angle mould pressing and shearing mould grid by using extrusion; setting the constant speed of the angular die pressing and shearing die grid along the Z-axis direction; generating an interface and a sample grid; setting interface material parameters; setting a sample grid constitutive model and material parameters; defining a FISH function monitoring and recording compression load and compression displacement by using the FISH function monitoring; defining a FISH function softening and utilizing the FISH function softening to realize the softening of the interfacial material parameters between the sample grids; setting an initial speed of downward loading; calculated by using a time step mode. The application does not need to purchase a press machine, a sensor and an angle die pressing and shearing die, does not relate to sample processing and polishing, and has no potential safety hazard; and moreover, the distribution rule of the displacement field inside the sample in the angular mould pressing shear test process can be analyzed, and researchers can be helped to better reveal the shear failure mechanism and the shear failure process of the sample based on the analysis of microscopic data.
Description
Technical Field
The application belongs to the field of geotechnical engineering numerical simulation, and particularly relates to a numerical simulation method for an angle modeling compression shear experiment.
Background
The angle mould pressing shear test is an effective method for measuring the shear properties of materials such as rock, cement mortar, concrete and the like. Compared with shearing methods such as triaxial compression experiments and direct shearing experiments, the angle die compression shearing experiments do not need equipment such as confining pressure sleeves and direct shearing boxes. The angle mould pressing shear experiment can be completed by only using a conventional press machine and an angle mould pressing shear die, and the experimental method is simpler.
However, the corner die press shearing experiment has certain defects. First, the specimens required for the corner-die shear test are typically of cubic dimensions. This requires cutting and machining of rock, cement mortar blocks, concrete blocks. Therefore, sample preparation before the experiment is performed is complicated.
In addition, the results obtained from the corner die compression shear experiments are generally only macroscopic compressive load versus compressive displacement curves. Therefore, the results obtained by the angle compression shearing test are relatively single, and microscopic results such as displacement field distribution in the sample cannot be analyzed.
Finally, in the development process of the angle mould pressing shear test, the materials such as rock, cement mortar, concrete and the like to be tested can be subjected to shearing damage. However, brittle materials such as rock, cement mortar, concrete and the like may crack when they are broken by shearing. Thus, the physical experiment may pose a security threat to the experimenter. To avoid this safety hazard, many laboratories are isolated using shielded doors and the like. But the shield door can prevent the experimenter from viewing the shear failure process of the test sample. Therefore, there is a certain contradiction in ensuring the safety of the test and observing the dynamic shearing process of the test sample.
In order to make up for the defects of physical experiments, numerical simulation has been widely used in various industries as an efficient research means. Compared with physical experiments, the numerical simulation does not need to purchase experimental equipment such as an experimental machine, an angular die pressing and shearing die and the like, does not need to cut and polish physical samples and the like, and has stronger operability.
In addition, a user can conveniently arrange a measuring line in the sample and extract microscopic data such as a displacement field when performing numerical simulation. Therefore, compared with a physical experiment, numerical simulation is convenient for a user to analyze microscopic results such as displacement field distribution and the like in the experimental process.
Finally, the numerical simulation is calculated in a time step iteration mode, the time step iteration times can be set by a user, and the flexibility is high. In the iterative computation process, a user can automatically pause the iterative computation according to the requirement so as to observe the destructive form and displacement field distribution state of the sample in the numerical simulation. Thus, numerical modeling facilitates a user to better analyze the dynamic destructive process of the sample.
However, through the research of the prior literature and patent, few numerical simulation researches relate to the corner molding shear experiment. Therefore, the numerical simulation method for the angle compression shear test is provided, and has important significance for revealing the shear failure mechanism of the test sample.
Disclosure of Invention
The application aims to provide a numerical simulation method for an angle die pressing and shearing experiment. The application overcomes the defect that the experimental result obtained by the angle mould pressing shear physical experiment is single, and can better reveal the shear failure mechanism of the sample to be tested in the angle mould pressing shear experiment process.
The application adopts the following technical scheme to provide a numerical simulation method for an angle die pressing and shearing experiment, which comprises the following steps: drawing a planar geometric figure of the angle die pressing and shearing die in AutoCAD; importing an AutoCAD file into FLAC3D and generating an upper three-dimensional angle die pressing and shearing die grid and a lower three-dimensional angle die pressing and shearing die grid by using an extrusion function; the upper and lower corner die pressing and shearing die grids are respectively named as plate_top and plate_bottom; giving an elastic model and material parameters to the diagonal mould pressing shear mould grid; setting the constant speed of the angular die pressing and shearing die grid along the Z-axis direction; generating an interface with ID of 1 on the bottom surface of the plate_top angle die-pressing and shearing die grid and the top surface of the plate_bottom angle die-pressing and shearing die grid; generating a sample grid above the plate_bottom angle die-pressing and shearing die grid and naming the sample grid as a bottom; generating an interface with ID of 2 on the top surface of the bottom sample grid; setting material parameters of interfaces with ID of 1 and ID of 2; generating a sample grid above an interface with ID of 2 and naming the sample grid as top; setting a constitutive model and material parameters of a bottom sample grid and a top sample grid, and setting a large deformation calculation mode as false; defining a FISH function monitoring and recording compression load and compression displacement by using the FISH function monitoring; defining a FISH function softening and using the FISH function softening to realize interface material parameter softening with an ID of 2; setting an initial downward loading speed for a plate_top angle die pressing and shearing die grid; and calculating in a time step mode until the end.
As a further description of the above technical solution:
the bottom sample grid and the top sample grid are the same in size and are of cuboid structures, the length and the width are equal, and the height is one half of the width.
As a further description of the above technical solution:
the bottom sample grid and the top sample grid are both generated by defining nodes not connected with the existing grid.
As a further description of the above technical solution:
the interface material parameters with ID of 1 comprise interface node shear rigidity and interface node normal rigidity, wherein the interface node shear rigidity and the interface node normal rigidity are both 500GPa.
As a further description of the above technical solution:
the interface material parameters with ID of 2 comprise interface node shear rigidity, interface node normal rigidity, interface node cohesion and interface node initial friction angle.
As a further description of the above technical solution:
the material parameters of the plate_top angle die-pressing and shearing die grid, the plate_bottom angle die-pressing and shearing die grid, the bottom sample grid and the top sample grid all comprise Young modulus and Poisson's ratio.
As a further description of the above technical solution:
the FISH function monitoring logic structure is as follows: defining a variable temp as zero; searching a node head pointer and assigning the node head pointer to a variable gridpoints; setting a cycle, judging whether gridpoints are empty or not, and if not, entering the cycle; in the circulation process, judging whether the current node falls on the bottom surface of the plate_bottom angle die-pressing and shearing die grid; if so, taking out the unbalanced force of the current node along the Z-axis direction, adding the unbalanced force and temp, and assigning the value to temp; gridpoints point to the next node and loops again; if not, the gridpoints directly point to the next node and loops again; ending the cycle when gridpoints are empty; after the cycle is completed, assigning temp to a variable force_z, wherein force_z is a compression load; the current time step is multiplied by the initial velocity of the downward load and assigned to variable disp_z, which is the compression displacement.
As a further description of the above technical solution:
the FISH function softening logic structure is as follows: searching an interface pointer with ID of 2 and assigning the interface pointer to a variable interface_address; searching an interface node head pointer corresponding to the interface_address and assigning the interface node head pointer to the variable interface_node_address; setting a loop, and judging whether the interface_node_address is empty or not; if not, entering a cycle; judging whether the node slip state corresponding to the interface_node_address is less than 2; if yes, updating the interface node friction angle corresponding to the interface_node_address; providing that the updated interface node friction angle is less than the interface node initial friction angle; interface_node_address points to the next interface node and loops again; if not, the interface_node_address directly points to the next interface node and loops again; when interface_node_address is empty, the loop ends.
The beneficial effects of the application mainly comprise the following four aspects:
1. the application provides a numerical simulation method for an angle die pressing and shearing experiment. By using the method provided by the application, researchers can simulate the angular mould pressing shearing experimental process by using numerical simulation software only. The whole simulation process does not need to purchase a press machine, a sensor, an angle die pressing and shearing die and the like additionally, and does not involve working procedures such as machining and polishing the sample, so that the operability is high. In addition, as no physical experiment is required to be carried out, the method provided by the application does not involve potential safety hazards such as shearing and cracking of the sample.
2. The tool used in the application is FLAC3D numerical simulation software. In the application, a FISH function monitoring is designed and can be used for recording compression load and compression displacement, so that a numerical simulation result and a physical experiment result can be compared. In addition, by utilizing FLAC3D numerical simulation software, the test line can be arranged in the sample and the distribution of the displacement field in the sample can be extracted, so that the distribution rule of the displacement field in the sample in the angular mould pressing shear test process can be analyzed. The defect that the physical experiment of the angle mould pressing shear can only obtain macroscopic results such as compression load, compression displacement and the like can be overcome. Therefore, based on analysis of microscopic data, researchers can be helped to better reveal the shear failure mechanism of the sample to be tested.
3. The FLAC3D used in the present application is calculated based on a time-step iterative approach. In the calculation process, a user can automatically pause iterative calculation and check the damage form of the sample to be tested in the numerical simulation according to the requirements. This helps researchers to dynamically analyze the shear failure process of the test sample.
4. The application designs FISH function softening. By utilizing the FISH function softening, a user can set the conditions of softening and attenuating friction angles of the damaged surfaces after shearing damage of the sample to be detected according to the needs. Therefore, the mechanical behavior of load attenuation after peak after shear failure of the sample to be tested can be simulated based on the softened and attenuated friction angle. This overcomes the defect that the FLAC3D original interface cannot simulate the destructive behavior after the destructive surface peak.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate and together with the description serve to explain the application. In the drawings:
FIG. 1 is a diagram of the logic structure of a FISH function monitoring according to the present application;
FIG. 2 is a logical block diagram of FISH function softening according to the present application;
FIG. 3 is a geometric diagram of the grid of the angle die pressing and shearing die and the grid of the sample to be tested according to the application;
FIG. 4 is a diagram of the interface geometry of the present application;
FIG. 5 is a graph comparing the numerical simulation results with the physical experiment results of the present application;
FIG. 6 is a graph of the horizontal displacement profile of the present application taken from the line from the left end to the right end of the sample;
FIG. 7 is a graph of the vertical displacement profile of the present application taken from the line from the left end to the right end of the sample;
FIG. 8 is a graph of the horizontal displacement profile of the present application taken from a line from the top of the sample to the bottom of the sample;
fig. 9 is a graph showing the vertical displacement profile of the present application taken from the line from the top of the sample to the bottom of the sample.
Detailed Description
The application provides a numerical simulation method for an angle die pressing shear experiment, which comprises the following steps: drawing a planar geometric figure of the angle die pressing and shearing die in AutoCAD; importing an AutoCAD file into FLAC3D and stretching the FLAC3D towards a third dimension (Y-axis direction) by using an extrication function to generate an upper three-dimensional angle die pressing and shearing die grid and a lower three-dimensional angle die pressing and shearing die grid for simulating a pressing and shearing die; the upper and lower corner die pressing and shearing die grids are respectively named as plate_top and plate_bottom; giving an elastic model and material parameters to the diagonal mould pressing shear mould grid; setting the constant speed of the angular die pressing and shearing die grid along the Z-axis direction; generating an interface with ID of 1 on the bottom surface of the plate_top angle die-pressing and shearing die grid and the top surface of the plate_bottom angle die-pressing and shearing die grid; generating a sample grid above the plate_bottom angle die-pressing and shearing die grid and naming the sample grid as a bottom; generating an interface with ID of 2 on the top surface of the bottom sample grid; setting material parameters of interfaces with ID of 1 and ID of 2; generating a sample grid above an interface with ID of 2 and naming the sample grid as top; setting a constitutive model and material parameters of a bottom sample grid and a top sample grid, and setting a large deformation calculation mode as false; defining a FISH function monitoring and recording compression load and compression displacement by using the FISH function monitoring; defining a FISH function softening and using the FISH function softening to realize interface material parameter softening with an ID of 2; setting an initial downward loading speed for a plate_top angle die pressing and shearing die grid; and calculating in a time step mode until the end.
In one embodiment:
the bottom sample grid and the top sample grid are the same in size and are of cuboid structures, the length and the width are equal, and the height is one half of the width.
In one embodiment:
the bottom sample grid and the top sample grid are both generated by defining nodes not connected with the existing grid.
In one embodiment:
the interface material parameters with ID of 1 comprise interface node shear rigidity and interface node normal rigidity, wherein the interface node shear rigidity and the interface node normal rigidity are both 500GPa.
In one embodiment:
the interface material parameters with ID of 2 comprise interface node shear rigidity, interface node normal rigidity, interface node cohesion and interface node initial friction angle.
In one embodiment:
the material parameters of the plate_top angle die-pressing and shearing die grid, the plate_bottom angle die-pressing and shearing die grid, the bottom sample grid and the top sample grid all comprise Young modulus and Poisson's ratio.
In one embodiment:
the FISH function monitoring logic structure is as follows: defining a variable temp as zero; searching a node head pointer and assigning the node head pointer to a variable gridpoints; setting a cycle, judging whether gridpoints are empty or not, and if not, entering the cycle; in the circulation process, judging whether the current node falls on the bottom surface of the plate_bottom angle die-pressing and shearing die grid; if so, taking out the unbalanced force of the current node along the Z-axis direction, adding the unbalanced force and temp, and assigning the value to temp; gridpoints point to the next node and loops again; if not, the gridpoints directly point to the next node and loops again; ending the cycle when gridpoints are empty; after the cycle is completed, assigning temp to a variable force_z, wherein force_z is a compression load; the current time step is multiplied by the initial velocity of the downward load and assigned to variable disp_z, which is the compression displacement.
In one embodiment:
the FISH function softening logic structure is as follows: searching an interface pointer with ID of 2 and assigning the interface pointer to a variable interface_address; searching an interface node head pointer corresponding to the interface_address and assigning the interface node head pointer to the variable interface_node_address; setting a loop, and judging whether the interface_node_address is empty or not; if not, entering a cycle; judging whether the node slip state corresponding to the interface_node_address is less than 2; if yes, updating the interface node friction angle corresponding to the interface_node_address; providing that the updated interface node friction angle is less than the interface node initial friction angle; interface_node_address points to the next interface node and loops again; if not, the interface_node_address directly points to the next interface node and loops again; when interface_node_address is empty, the loop ends.
In order to check the effectiveness of the present application, a simulation was carried out taking as an example the physical test of corner die press shear developed in the paper "a design of shear die and its teaching application" (Chen Jianhang, experimental techniques and administration, 2022, 11 months, 39, 11 th edition, pages 56-60). The paper designs an angle die-pressing and shearing die with an inclination angle of 38 degrees and develops an indoor angle die-pressing and shearing experiment.
The numerical simulation method provided by the application is adopted to simulate the angular compression shearing experimental process in the paper. First, an angular die press-shear die geometry with an inclination angle of 38 ° was drawn in AutoCAD. The AutoCAD file was then imported into FLAC3D and an extrication function was used to generate the upper and lower corner molding press mold grids. The upper and lower corner molding shear mold grids are designated as plate_top and plate_bottom, respectively. And an elastic model and material parameters are given to the diagonal compression molding shear mold grid, wherein the Young modulus in the material parameters is 200GPa, and the Poisson ratio is 0.2. And setting the angular die pressing and shearing die grid to have constant speed along the Z-axis direction. An interface with ID 1 is generated on the bottom surface of the plate_top corner die-stamping shear die grid and the top surface of the plate_bottom corner die-stamping shear die grid. A sample grid was generated above the plate_bottom corner die shear mold grid and named bottom. The bottom sample grid has a cuboid structure, the length and the width are both 50mm, and the height is 25mm.
An interface with an ID of 2 is created on the top surface of the bottom sample grid. And setting an interface material parameter with an ID of 1, wherein the shear stiffness of an interface node and the normal stiffness of the interface node are 500GPa. The interface material parameters were set to ID 2, where the interface node shear stiffness was 500GPa, the interface node normal stiffness was 500GPa, the interface node cohesion was 39MPa, and the interface node initial friction angle was 35. A grid is generated above the interface with ID 2 and named top. the top sample grid size is the same as the bottom sample grid size. The bottom sample grid and the top sample grid are both generated by defining nodes not connected with the existing grid.
And setting a bottom sample grid and a top sample grid constitutive model as an elastic model. Material parameters of a bottom sample grid and a top sample grid were set, wherein young's modulus was 15GPa, poisson ratio was 0.2, and a large deformation calculation mode was false.
A FISH function monitoring is defined, the logic structure of the FISH function monitoring is shown in figure 1, and the FISH function monitoring is used for recording compression load and compression displacement.
FISH function softening is defined, the logical structure of which is shown in fig. 2. In FISH function softening, the interface node friction angle drops to 32 ° after an interface shear failure with specified ID of 2. Interface node friction angle softening with ID 2 was achieved using FISH function softening.
Setting initial downward loading speed of 1×10 for plate_top angle die-pressing and shearing die grid -6 m/s. The time step number is set to 11000 and the calculation is carried out to the end by using a time step mode.
In the calculation process, the geometry of the corner die stamping shear die grid and the sample grid is shown in fig. 3. The arrow direction in the figure is the displacement field distribution trend. It can be seen that the upper corner molding shear die has a significant tendency to move to the right while moving downward. This is consistent with the horizontal rightward sliding tendency of the upper corner molding shear die in physical experiments. Further, in the numerical simulation, the lower corner molding shear die slides horizontally leftward. This is consistent with the horizontal left sliding trend of the lower corner molding shear die in physical experiments. The movement trend of the upper and lower corner die-pressing and shearing dies is consistent with that of the corner die-pressing and shearing dies in a physical experiment, and the effectiveness of a numerical simulation result is reflected.
The interface geometry set in the numerical simulation is shown in fig. 4. After the calculation is finished, the compression load and compression displacement relation curve extracted from the numerical simulation is compared with the compression load and compression displacement relation curve in the physical experiment, as shown in fig. 5. And the overall trend and peak load of the numerical simulation result and the physical experiment result are highly consistent, and the accuracy of the numerical simulation result is checked again. In addition, in numerical simulation, after the compression load reaches a peak value, the bearing capacity gradually decreases, and the decreasing trend is consistent with the physical experiment result. This demonstrates that FISH function softening set by the present application effectively reduces the shear capacity of the specimen.
Compared with a physical experiment, the application can obtain macroscopic data of compression load and compression displacement relation curve, and can explore the distribution rule of the displacement field in the sample. For example, a line of measurement from the left end point to the right end point may be arranged inside the sample, as indicated by the broken line in fig. 6. By using this measuring line, displacement data in the horizontal direction (X-axis direction) and displacement data in the vertical direction (Z-axis direction) inside the sample can be extracted as shown in fig. 6 and fig. 7, respectively. It can be seen that the left portion of the sample has a tendency to move downward to the left and the right portion has a tendency to move downward to the right. The sample left and right portions have different movement tendencies, causing shearing of the sample along the interface direction with ID 2.
Similarly, a line of sight may be disposed between the top of the sample and the bottom of the sample, as shown by the dashed lines in FIG. 8. By using this measuring line, displacement data in the horizontal direction (X-axis direction) and displacement data in the vertical direction (Z-axis direction) inside the sample can be extracted as shown in fig. 8 and 9, respectively. The top end of the sample tends to move downward and rightward, and the bottom end of the sample tends to move downward and leftward. The displacement of the downward movement of the bottom end of the sample is obviously larger than that of the top end of the sample. Therefore, in the horizontal direction, the movement tendencies of the sample top end and the sample bottom end are opposite. In the vertical direction, the movement trend of the sample top end and the sample bottom end is the same, but the displacement of the sample bottom end is obviously larger than that of the sample top end. This results in an overall tendency for the specimen to rotate in a clockwise direction during shearing. This is consistent with the displacement field distribution trend (arrow direction) of fig. 3, and the validity of the numerical simulation results was again examined while revealing the specimen shear failure mechanism.
The present application is not limited to the above-mentioned preferred embodiments, and any person who can obtain other various products under the teaching of the present application can make any changes in shape or structure, and all the technical solutions that are the same or similar to the present application fall within the scope of the present application.
Claims (3)
1. The numerical simulation method for the angle die pressing and shearing experiment comprises the following steps: drawing a planar geometric figure of the angle die pressing and shearing die in AutoCAD; importing an AutoCAD file into FLAC3D and generating an upper three-dimensional angle die pressing and shearing die grid and a lower three-dimensional angle die pressing and shearing die grid by using an extrusion function; the upper and lower corner die pressing and shearing die grids are respectively named as plate_top and plate_bottom; giving an elastic model and material parameters to the diagonal mould pressing shear mould grid; setting the constant speed of the angular die pressing and shearing die grid along the Z-axis direction; generating an interface with ID of 1 on the bottom surface of the plate_top angle die-pressing and shearing die grid and the top surface of the plate_bottom angle die-pressing and shearing die grid; generating a sample grid above the plate_bottom angle die-pressing and shearing die grid and naming the sample grid as a bottom; generating an interface with ID of 2 on the top surface of the bottom sample grid; setting material parameters of interfaces with ID of 1 and ID of 2; generating a sample grid above an interface with ID of 2 and naming the sample grid as top; setting a constitutive model and material parameters of a bottom sample grid and a top sample grid, and setting a large deformation calculation mode as false; defining a FISH function monitoring and recording compression load and compression displacement by using the FISH function monitoring; defining a FISH function softening and using the FISH function softening to realize interface material parameter softening with an ID of 2; setting an initial downward loading speed for a plate_top angle die pressing and shearing die grid; calculating by using a time step mode until the calculation is finished;
the FISH function monitoring logic structure is as follows: defining a variable temp as zero; searching a node head pointer and assigning the node head pointer to a variable gridpoints; setting a cycle, judging whether gridpoints are empty or not, and if not, entering the cycle; in the circulation process, judging whether the current node falls on the bottom surface of the plate_bottom angle die-pressing and shearing die grid; if so, taking out the unbalanced force of the current node along the Z-axis direction, adding the unbalanced force and temp, and assigning the value to temp; gridpoints point to the next node and loops again; if not, the gridpoints directly point to the next node and loops again; ending the cycle when gridpoints are empty; after the cycle is completed, assigning temp to a variable force_z, wherein force_z is a compression load; multiplying the current time step by the initial speed of downward loading and assigning the initial speed to a variable disp_z, wherein disp_z is compression displacement;
the FISH function softening logic structure is as follows: searching an interface pointer with ID of 2 and assigning the interface pointer to a variable interface_address; searching an interface node head pointer corresponding to the interface_address and assigning the interface node head pointer to the variable interface_node_address; setting a loop, and judging whether the interface_node_address is empty or not; if not, entering a cycle; judging whether the node slip state corresponding to the interface_node_address is less than 2; if yes, updating the interface node friction angle corresponding to the interface_node_address; providing that the updated interface node friction angle is less than the interface node initial friction angle; interface_node_address points to the next interface node and loops again; if not, the interface_node_address directly points to the next interface node and loops again; ending the cycle when the interface_node_address is empty;
the interface material parameter with the ID of 1 comprises interface node shear rigidity and interface node normal rigidity, wherein the interface node shear rigidity and the interface node normal rigidity are both 500GPa;
the interface material parameters with ID of 2 comprise interface node shear rigidity, interface node normal rigidity, interface node cohesion and interface node initial friction angle;
the material parameters of the plate_top angle die-pressing and shearing die grid, the plate_bottom angle die-pressing and shearing die grid, the bottom sample grid and the top sample grid all comprise Young modulus and Poisson's ratio.
2. The numerical simulation method of the angle modeling compression shear test according to claim 1, wherein the bottom sample grid and the top sample grid are the same in size, are both cuboid structures, are equal in length and width, and are half of the width in height.
3. The numerical simulation method of angle modeling shear test according to claim 1, wherein the bottom sample grid and the top sample grid are each formed with a node that is not connected to an existing grid.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311103772.3A CN116844679B (en) | 2023-08-30 | 2023-08-30 | Numerical simulation method for angle die compression shear experiment |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202311103772.3A CN116844679B (en) | 2023-08-30 | 2023-08-30 | Numerical simulation method for angle die compression shear experiment |
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| CN116844679A CN116844679A (en) | 2023-10-03 |
| CN116844679B true CN116844679B (en) | 2023-11-14 |
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| CN102866049A (en) * | 2012-10-08 | 2013-01-09 | 中国科学院武汉岩土力学研究所 | Method and device for preparing tri-axial test samples including sandwich layers |
| CN108170959A (en) * | 2017-12-28 | 2018-06-15 | 天地科技股份有限公司 | Mechanical response of the rock mass numerical analysis method and device based on discrete element |
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| CN102866049A (en) * | 2012-10-08 | 2013-01-09 | 中国科学院武汉岩土力学研究所 | Method and device for preparing tri-axial test samples including sandwich layers |
| CN108170959A (en) * | 2017-12-28 | 2018-06-15 | 天地科技股份有限公司 | Mechanical response of the rock mass numerical analysis method and device based on discrete element |
| CN109696363A (en) * | 2019-03-04 | 2019-04-30 | 山东科技大学 | A kind of rock compression shear test device and test method |
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