A Finite Element Method for Calculating Creep Material Contact in Mining

Abstract

A finite element method creep material contact calculation method for mines, belonging to the field of intelligent mines and numerical simulation, obtains survey data; forms a solution file based on the survey data; generates working condition data; defines a pseudo-physical state in the working condition; in the pseudo-physical state, calculates the displacement generated by creep according to statics and updates the node displacement, including updating the coordinates of the solution domain nodes and boundary nodes. The contact algorithm based on the finite element statics calculation of creep problems converts the dynamic solution method into a static solution, and converts the iterative calculation that originally requires multiple time steps into a pseudo-physical state for solution, avoiding the problem that the dynamic problem is difficult to converge after increasing the time step. The contact algorithm based on the FEM statics calculation of creep problems greatly improves the efficiency of the calculation, while avoiding the problem that the dynamic solution is difficult to converge, providing a fast analysis method for the working face recovery of intelligent mines.

Description

Technical Field

[0001] The invention belongs to the field of intelligent mines and numerical simulation, and in particular relates to a finite element method creep material contact calculation method for mines. Background Art

[0002] In recent years, the finite element method has developed rapidly and has become an important tool for mechanical analysis in the fields of geotechnical engineering, mining engineering, and water conservancy engineering. Using the finite element method to calculate the creep drop of the working face after tunnel excavation belongs to the solution of dynamic problems. However, the current numerical simulation often uses static simulation of elastic-plastic mechanics, which has a long time scale and is not dynamically coupled with the real-time data obtained from production. It does not meet the requirements of real-time simulation and prediction of intelligent mine construction.

[0003] The dynamic solution is to use a discrete method to calculate the creep time of the working surface, divide the creep time into several time steps, and iterate and solve each time step to calculate the displacement to describe the entire creep process. In the process of calculating creep, the contact algorithm needs to define the matching relationship between the contact surfaces, and at the same time, the contact surface is judged in each time step. After the contact is released, the time step is adjusted accordingly according to the calculated displacement. When the two contact surfaces are in contact, the appropriate contact load is applied to the contact surface to ensure that the contact surface does not penetrate.

[0004] There are two problems in the existing dynamic solution of creep. One is that on a real time scale, creep time is usually long. When using dynamic solution, the time step is relatively high. The time of the iterative step of the calculation needs to be set very small, otherwise it will not converge. This will cause the entire calculation process to require a lot of time steps, making the calculation very large. The other is that after adding contact during the creep process, a search needs to be performed in each time step. The dynamic solution requires a lot of time steps, so the search and calculation cost of the contact surface is also very high in calculation, which leads to a long time and low efficiency in the entire solution process. Summary of the invention

[0005] The present invention aims to solve the above problems and provides a contact algorithm for calculating creep problems based on finite element statics, which is used to quickly calculate the related problems of working face collapse caused by creep during mining.

[0006] In a first aspect, the present invention provides a finite element method creep material contact calculation method for mines, comprising the following steps:

[0007] Step 1, obtaining survey data; forming a solution file according to the survey data;

[0008] Step 2, obtaining real-time monitoring data; defining excavation conditions and boundary information according to the real-time monitoring data, and generating condition data;

[0009] Step 3, define a pseudo-physical state in the working condition; the pseudo-physical state is an unreal physical state obtained by solving the instant when the top plate falls directly at the moment of excavation;

[0010] In the pseudo-physical state, the displacement caused by creep is calculated according to statics and the node displacement is updated, including updating the coordinates of the solution domain nodes and boundary nodes;

[0011] In the boundary load matrix of the assembled stiffness matrix, two contact surfaces that will come into contact are specified, and all the specified boundary units BCElements are traversed; the specified boundary units include contact units and non-contact units; the nodes in a boundary unit BCElement are traversed, and the distance judgment of the first node P corresponding to the specified contact boundary unit is performed to find the nearest node D, and the search is performed based on node D. The boundary unit containing node D is NElements;

[0012] Determine whether the node P and one of the boundary elements NElement will penetrate each other; if no contact surface penetration occurs, continue to traverse the nodes in BCElement; if contact surface penetration occurs, the boundary element containing the normal N is the current calculation element NElement;

[0013] Calculate the foot of the perpendicular F of point P in the neement, and determine whether point F is inside the neement; if point F is outside the neement, continue to make a penetration judgment on another neement; if it is inside the neement, calculate the projection of the penetration amount on the normal direction of the contact surface Delta ;

[0014] Step 4, in the pseudo-physical process, the penetration displacement is corrected;

[0015] Step 5: After the correction is completed, the overall contact load is scaled to prevent the contact load from being too large, which will cause the correction load to be too large; the correction load guarantees Delta The calculation converges to the preset range and the pseudo-physical state ends;

[0016] Step 6, continue to solve the creep based on statics, so as to dynamically correct the load on the contact surface until the iteration is completed;

[0017] Step 7: Update the entire solution domain, and the calculation result is the result after excavation.

[0018] Furthermore, in the finite element method for creep material contact calculation for mines of the present invention, the range of the modified iteration steps defined in the pseudo-physical state is 15-30 steps.

[0019] Furthermore, in the finite element method for calculating creep material contact for mines of the present invention, the projection of the penetration amount on the normal direction of the contact surface is Delta The calculation is based on the following formula, Delta = ,in V is the vector PF, N is the unit vector of the face normal of the NELement unit.

[0020] Furthermore, in the finite element method for creep material contact calculation method for mines of the present invention, when the penetration displacement is corrected in step 4, the correction load is performed in a superposition manner, and the contact load superimposed in the iterative step is B=B+b , b= ,in E is the contact stiffness of the two contact surfaces, A1 is the average area of ​​the boundary elements connected to the node P, and A2 is the average area of ​​the elements penetrating the point P in the NELement.

[0021] Furthermore, in the finite element method creep material contact calculation method for mines of the present invention, when scaling the overall contact load in step 5, B=aB ;in a is the scaling factor, and the scaling factor ranges from 0.5 to 0.99.

[0022] Furthermore, in the finite element method for creep material contact calculation for mines of the present invention, the survey data includes geometric model data and material data of the strata matching the geometric model data.

[0023] Furthermore, in the finite element method for creep material contact calculation for mines described in the present invention, the real-time monitoring data includes time data of excavation, excavation range data and boundary information of the excavation working face.

[0024] In a second aspect, the present invention provides a finite element method creep material contact calculation system for mines, comprising an acquisition module, a calculation module and an output module;

[0025] The acquisition module is used to acquire survey data; form a solution file based on the survey data; acquire real-time monitoring data; define excavation conditions and boundary information based on the real-time monitoring data, and generate condition data;

[0026] The calculation module is used to define a pseudo-physical state in the working condition; in the pseudo-physical state, the displacement generated by creep is calculated according to statics and the node displacement is updated, including updating the coordinates of the solution domain nodes and boundary nodes;

[0027] In the boundary load matrix of the assembled stiffness matrix, two contact surfaces that will come into contact are specified, and all the specified boundary units BCElements are traversed; the specified boundary units include contact units and non-contact units; the nodes in a boundary unit BCElement are traversed, and the distance judgment of the first node P corresponding to the specified contact boundary unit is performed to find the nearest node D, and the search is performed based on node D. The boundary unit containing node D is NElements;

[0028] Determine whether the node P and one of the boundary elements NElement will penetrate each other; if no contact surface penetration occurs, continue to traverse the nodes in BCElement; if contact surface penetration occurs, the boundary element containing the normal N is the current calculation element NElement;

[0029] Calculate the foot of the perpendicular F of point P in the neement, and determine whether point F is inside the neement; if point F is outside the neement, continue to make a penetration judgment on another neement; if it is inside the neement, calculate the projection of the penetration amount on the normal direction of the contact surface Delta ; In the pseudo-physical process, the penetration displacement is corrected; after the correction is completed, the overall contact load is scaled; the corrected load ensures Delta The calculation converges to the preset range and the pseudo-physical state ends;

[0030] Continue to solve the creep based on statics to dynamically correct the load on the contact surface until the iteration ends; then update the entire solution domain, and the calculation result is the result after excavation;

[0031] The output module is used to output the calculation results, that is, the results after excavation.

[0032] In a third aspect, the present invention provides a finite element method creep material contact calculation device for mines, comprising a memory and a processor; the memory is used to store a computer program; the processor is used to implement the finite element method creep material contact calculation method for mines described in the first aspect when executing the computer program.

[0033] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the finite element method creep material contact calculation method for mines described in the first aspect is implemented.

[0034] The finite element method creep material contact calculation method for mines described in the present invention is based on the contact algorithm of the finite element statics calculation of creep problems, which converts the dynamic solution method into a static solution, and converts the iterative calculation that originally requires multiple time steps into a pseudo-physical state for solution, thereby avoiding the problem that the dynamic problem is difficult to converge after increasing the time step. The contact algorithm based on the FEM statics calculation of creep problems greatly improves the calculation efficiency and shortens the calculation time, while avoiding the problem that the dynamic solution is difficult to converge, and provides a rapid analysis method for the working face recovery of intelligent mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic flow chart of a finite element method creep material contact calculation method for mines according to an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the point P penetrating inside the computing unit according to an embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram of the point P penetrating outside the computing unit according to an embodiment of the present invention;

[0038] Figure 4 A schematic diagram of an excavation model extracted from exploration data according to an embodiment of the present invention;

[0039] Figure 5 A schematic diagram of the upper and lower boundaries of the excavation area included in the model of the embodiment of the present invention;

[0040] Figure 6 This is a schematic diagram of the deformation of the units after contact after excavation of 50 meters according to an embodiment of the present invention;

[0041] Figure 7 This is a schematic diagram of the deformation of the units after contact after excavation of 100 meters according to an embodiment of the present invention;

[0042] Figure 8 This is a schematic diagram of the deformation of the units after contact after excavation of 150 meters according to an embodiment of the present invention;

[0043] Fig. 9 This is a schematic diagram of the deformation of the units after contact after excavation of 200 meters according to an embodiment of the present invention;

[0044] Fig.10This is a schematic diagram of the deformation of the units after contact after excavation of 250 meters according to an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The finite element method creep material contact calculation method for mines of the present invention is described in detail below through the accompanying drawings and embodiments.

[0046] Embodiment 1

[0047] This embodiment discloses a finite element method creep material contact calculation method for mines, such as Figure 1 As shown, the following steps are included:

[0048] Step 1, obtaining survey data; forming a solution file according to the survey data;

[0049] Step 2, obtaining real-time monitoring data; defining excavation conditions and boundary information according to the real-time monitoring data, and generating condition data;

[0050] Step 3, define a pseudo-physical state in the working condition; the pseudo-physical state is an unreal physical state obtained by solving the instant when the top plate falls directly at the moment of excavation;

[0051] In the pseudo-physical state, the displacement caused by creep is calculated according to statics and the node displacement is updated, including updating the coordinates of the solution domain nodes and boundary nodes;

[0052] In the boundary load matrix of the assembled stiffness matrix, two contact surfaces that will come into contact are specified, and all the specified boundary units BCElements are traversed; the specified boundary units include contact units and non-contact units; the nodes in a boundary unit BCElement are traversed, and the distance judgment of the first node P corresponding to the specified contact boundary unit is performed to find the nearest node D, and the search is performed based on node D. The boundary unit containing node D is NElements;

[0053] Determine whether the node P will penetrate one of the boundary elements NElement; if the contact surface penetration does not occur, continue to traverse the nodes in BCElement; if the contact surface penetration occurs, the boundary element containing the normal N is the current calculation element NElement; Figure 2 , Figure 3 As shown, the bold part is the boundary element, and the boundary element containing the normal N is the current calculation element NElement;

[0054] Calculate the foot of the perpendicular F of point P in the neement, and determine whether point F is inside the neement; if point F is outside the neement, continue to make a penetration judgment on another neement; if it is inside the neement, calculate the projection of the penetration amount on the normal direction of the contact surface Delta ;

[0055] Step 4: In the pseudo-physical process, the penetration displacement is corrected; the range of the corrected iteration step is 15-30 steps; the corrected load is superimposed, and the contact load superimposed by the iteration step is B=B+b , b= ,in E is the contact stiffness of the two contact surfaces, A1 is the average area of ​​the boundary elements connected to the node P, and A2 is the average area of ​​the elements penetrating the point P in the NELement;

[0056] Step 5: After the correction is completed, the overall contact load is scaled to prevent the contact load from being too large, which will cause the correction load to be too large; the correction load guarantees Delta The calculation converges to the preset range and the pseudo-physical state ends; when the overall contact load is scaled, B=aB ;in a is the scaling factor, and the scaling factor ranges from 0.5 to 0.99;

[0057] Step 6, continue to solve the creep based on statics, so as to dynamically correct the load on the contact surface until the iteration is completed;

[0058] Step 7: Update the entire solution domain, and the calculation result is the result after excavation.

[0059] In the embodiment of the present disclosure, the projection of the penetration amount on the normal direction of the contact surface is Delta The calculation is based on the following formula, Delta = ， in V is the vector PF, N is the unit vector of the face normal of the NELement unit.

[0060] In the embodiments of the present disclosure, Figure 4 As shown, a 300M*50M*70M excavation stratum is extracted through exploration data, a 10Mpa pressure boundary condition is applied to the upper part of the stratum, and a boundary condition with full freedom constraints is adopted at the bottom.

[0061] Through real-time excavation data, the boundary information of the upper and lower bottom surfaces of the excavation, the time and speed of the excavation, etc. are determined. The data provided in this embodiment is that the excavation height is 5M, the excavation length is 250M, the excavation is divided into five times, and the excavation time is 3600s. Figure 5 Shown is the developed area, including the upper and lower boundary information of the working face.

[0062] In the disclosed embodiment, a pseudo-physical time process is defined in each excavation and falling process, with 30 iterations and each time lasting 0.001 s.

[0063] The formation data includes reference temperature, creep parameters, material density, Young's modulus, Poisson's ratio, pressure information of the formation, boundary information, etc.

[0064] All the stratum data, excavation data shapes, and the selected solution method are solved by the mine-oriented finite element method creep material contact calculation method described in this embodiment to obtain the result after excavation.

[0065] like Figure 6-Figure 10 The following is the effect of adding contact to the creep problem based on FEM statics calculation. The following is the whole excavation process divided into five times, among which Figure 6 This is the deformation of the unit after contact after 50 meters of excavation; Figure 7 This is the deformation of the unit after contact after 100 meters of excavation; Figure 8 This is the deformation of the units after contact after 150 m of excavation; Fig. 9 This is the deformation of the unit after contact after 200 meters of excavation; Fig.10 This is the deformation of the units after contact after 250 meters of excavation.

[0066] The finite element method creep material contact calculation method for mines described in this embodiment is based on the contact algorithm of FEM statics calculation creep problem, replaces the dynamic part containing the time discrete process, and adjusts the contact load between the contact surfaces so that the contact surfaces can quickly contact each other after the working surface creeps.

[0067] Embodiment 2

[0068] Based on the aforementioned embodiment 1, this embodiment discloses a finite element method creep material contact calculation system for mines, including an acquisition module, a calculation module and an output module;

[0069] The acquisition module is used to acquire survey data; form a solution file based on the survey data; acquire real-time monitoring data; define excavation conditions and boundary information based on the real-time monitoring data, and generate condition data;

[0070] The calculation module is used to define a pseudo-physical state in the working condition; in the pseudo-physical state, the displacement generated by creep is calculated according to statics and the node displacement is updated, including updating the coordinates of the solution domain nodes and boundary nodes;

[0071] In the boundary load matrix of the assembled stiffness matrix, two contact surfaces that will come into contact are specified, and all the specified boundary units BCElements are traversed; the specified boundary units include contact units and non-contact units; the nodes in a boundary unit BCElement are traversed, and the distance judgment of the first node P corresponding to the specified contact boundary unit is performed to find the nearest node D, and the search is performed based on node D. The boundary unit containing node D is NElements;

[0072] Determine whether the node P and one of the boundary elements NElement will penetrate each other; if no contact surface penetration occurs, continue to traverse the nodes in BCElement; if contact surface penetration occurs, the boundary element containing the normal N is the current calculation element NElement;

[0073] Calculate the foot of the perpendicular F of point P in the neement, and determine whether point F is inside the neement; if point F is outside the neement, continue to make a penetration judgment on another neement; if it is inside the neement, calculate the projection of the penetration amount on the normal direction of the contact surface Delta ;

[0074] In the pseudo-physical process, the penetration displacement is corrected; after the correction is completed, the overall contact load is scaled; the corrected load ensures Delta The calculation converges to the preset range and the pseudo-physical state ends;

[0075] Continue to solve the creep based on statics to dynamically correct the load on the contact surface until the iteration ends; then update the entire solution domain, and the calculation result is the result after excavation;

[0076] The output module is used to output the calculation results, that is, the results after excavation.

[0077] The process of implementing the finite element method creep material contact calculation system for mines described in this embodiment is the same as the finite element method creep material contact calculation method for mines described in the aforementioned embodiment 1, and will not be repeated here.

[0078] Embodiment 3

[0079] The present embodiment discloses a finite element method creep material contact calculation device for mines, comprising a memory and a processor; the memory is used to store a computer program; the processor is used to implement the finite element method creep material contact calculation method for mines described in the aforementioned embodiment 1 when executing the computer program; the specific calculation method steps are the same as those in the aforementioned embodiment 1 and will not be repeated here.

[0080] Embodiment 4

[0081] This embodiment discloses a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the finite element method creep material contact calculation method for mines described in the aforementioned embodiment 1 is implemented; the specific calculation method steps are the same as those in the aforementioned embodiment 1 and are not repeated here.

[0082] The computer described in the embodiment of the present application may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. The computer-readable storage medium may be any available medium that a computer can read or a data storage device such as a server or a data center that includes one or more available media integrations. The available medium may be a magnetic medium, (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a digital versatile disc (DVD)) or a semiconductor medium (e.g., a solid-state drive (SSD)), etc. The software formed by the computer storage code may be located in a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, and other mature storage media in the art.

[0083] Each functional module in each embodiment of the present application can be integrated into a processing unit or module, or each module can exist physically separately, or two or more modules can be integrated into one unit or module. In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When software is used for implementation, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part.

[0084] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A finite element method creep material contact calculation method for mines, characterized by The following steps are involved: Step 1, obtaining survey data; forming a solution file according to the survey data; Step 2, obtaining real-time monitoring data; defining excavation conditions and boundary information according to the real-time monitoring data, and generating condition data; Step 3, define a pseudo-physical state in the working condition; in the pseudo-physical state, calculate the displacement caused by creep according to statics and update the node displacement, including updating the coordinates of the solution domain nodes and boundary nodes; In the boundary load matrix of the assembled stiffness matrix, two contact surfaces that will come into contact are specified, and all the specified boundary units BCElements are traversed; the specified boundary units include contact units and non-contact units; the nodes in a boundary unit BCElement are traversed, and the distance judgment of the first node P corresponding to the specified contact boundary unit is performed to find the nearest node D, and the search is performed based on node D. The boundary unit containing node D is NElements; Determine whether the node P and one of the boundary elements NElement will penetrate each other; if no contact surface penetration occurs, continue to traverse the nodes in BCElement; if contact surface penetration occurs, the boundary element containing the normal N is the current calculation element NElement; Calculate the foot F of the perpendicular of point P in the nelement, and determine whether point F is inside the nelement; If point F is outside the nelem, continue to make a penetration judgment on another nelem; if it is inside the nelem, calculate the projection of the penetration amount on the normal direction of the contact surface Delta ; Step 4, in the pseudo-physical process, the penetration displacement is corrected; The modified load is carried out in a superposition manner, and the contact load superimposed in the iterative step is B=B+b , b= ,in E is the contact stiffness of the two contact surfaces, A1 is the average area of ​​the boundary elements connected to the node P, and A2 is the average area of ​​the elements penetrating the point P in the NELement; Step 5: After the correction is completed, scale the overall contact load; correct the load to ensure Delta The calculation converges to the preset range and the pseudo-physical state ends; when the overall contact load is scaled, B=aB ;in a is the scaling factor, and the scaling factor ranges from 0.5 to 0.99; Step 6, continue to solve the creep based on statics, so as to dynamically correct the load on the contact surface until the iteration is completed; Step 7: Update the entire solution domain, and the calculation result is the result after excavation.

2. The finite element method creep material contact calculation method for mines according to claim 1 is characterized by: The iterative steps for defining corrections under the pseudo-physical state range from 15 to 30 steps.

3. The finite element method creep material contact calculation method for mines according to claim 2 is characterized by: The projection of the penetration amount on the normal direction of the contact surface Delta The calculation is based on the following formula, Delta = ， in V is the vector PF, N is the unit vector of the face normal of the NELement unit.

4. The finite element method creep material contact calculation method for mines according to claim 3 is characterized by: The survey data includes geometric model data and material data of the formation matching the geometric model data.

5. The finite element method creep material contact calculation method for mines according to claim 4 is characterized by: The real-time monitoring data includes excavation time data, excavation range data and boundary information of the excavation working face.

6. A finite element method creep material contact calculation system for mines, characterized by: It includes an acquisition module, a calculation module and an output module; The acquisition module is used to acquire survey data and form a solution file according to the survey data; Obtain real-time monitoring data; define excavation conditions and boundary information based on the real-time monitoring data and generate condition data; The calculation module is used to define a pseudo-physical state in the working condition; In the pseudo-physical state, the displacement caused by creep is calculated according to statics and the node displacement is updated, including updating the coordinates of the solution domain nodes and boundary nodes; In the boundary load matrix of the assembled stiffness matrix, two contact surfaces that will come into contact are specified, and all the specified boundary units BCElements are traversed; the specified boundary units include contact units and non-contact units; the nodes in a boundary unit BCElement are traversed, and the distance judgment of the first node P corresponding to the specified contact boundary unit is performed to find the nearest node D, and the search is performed based on node D. The boundary unit containing node D is NElements; Determine whether the node P and one of the boundary elements NElement will penetrate each other; if no contact surface penetration occurs, continue to traverse the nodes in BCElement; if contact surface penetration occurs, the boundary element containing the normal N is the current calculation element NElement; Calculate the foot F of the perpendicular of point P in the nelement, and determine whether point F is inside the nelement; If point F is outside the nelem, continue to make a penetration judgment on another nelem; if it is inside the nelem, calculate the projection of the penetration amount on the normal direction of the contact surface Delta ; In the pseudo-physical process, the penetration displacement is corrected; The modified load is carried out in a superposition manner, and the contact load superimposed in the iterative step is B=B+b , b= ,in E is the contact stiffness of the two contact surfaces, A1 is the average area of ​​the boundary elements connected to the node P, and A2 is the average area of ​​the elements penetrating the point P in the NELement; After the correction is completed, the overall contact load is scaled; the correction load ensures Delta The calculation converges to the preset range and the pseudo-physical state ends; when the overall contact load is scaled, B=aB ;in a is the scaling factor, and the scaling factor ranges from 0.5 to 0.99; Continue to solve the creep based on statics to dynamically correct the load on the contact surface until the iteration ends; then update the entire solution domain, and the calculation result is the result after excavation; The output module is used to output the calculation results, that is, the results after excavation.

7. A finite element method creep material contact calculation device for mines, characterized by: It comprises a memory and a processor; the memory is used to store a computer program; the processor is used to implement the finite element method creep material contact calculation method for mines as described in any one of claims 1-5 when executing the computer program.

8. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by the processor, the finite element method creep material contact calculation method for mines as described in any one of claims 1 to 5 is implemented.

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