Method and device for determining thickness of filling retaining wall of stope

Abstract

The invention provides a stope filling retaining wall thickness determination method and device. The method comprises the steps that hydrostatic pressure when filling slurry does not exceed a retaining wall and additional pressure after the filling slurry exceeds the retaining wall are determined; the compressive thickness and the shear thickness of the retaining wall are calculated according to the hydrostatic pressure, and the larger value of the compressive thickness and the shear thickness serves as the initial theoretical thickness; constructing a three-dimensional numerical model of the retaining wall according to the initial theoretical thickness, and setting a stress load of the three-dimensional numerical model according to the hydrostatic pressure and the additional pressure; performing stability simulation on the three-dimensional numerical model to obtain a simulation result of the retaining wall; and performing iterative optimization on the initial theoretical thickness according to the simulation result to determine the final thickness of the retaining wall. The stope filling retaining wall thickness determining method and device are simple and convenient, high in accuracy and reliability and capable of achieving the optimal balance between the structural safety and the construction cost.

Description

Technical Field

[0001] This application relates to the field of backfill mining technology, and in particular to a method and apparatus for determining the thickness of a backfill retaining wall in a stope. Background Technology

[0002] With the development of deep mining and efficient recovery technologies for mineral resources, high-rise stopes are increasingly widely used in metal mines. As the primary recovery process in such stopes, the backfilling method relies heavily on the stability of the backfill retaining walls. These walls must not only withstand the static and dynamic loads of unconsolidated backfill slurry, but also maintain overall stability under complex environments of high stress and high seepage pressure. Otherwise, wall instability, water seepage, and slurry leakage may occur, seriously threatening underground operational safety and impacting production efficiency. Existing methods for determining retaining wall thickness are inaccurate, unsafe, and costly. Therefore, a method that can balance various performance aspects and achieve better results is urgently needed. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide a method and apparatus for determining the thickness of a backfill wall in a mining area to solve the above-mentioned technical problems.

[0004] A first aspect of this application provides a method for determining the thickness of a backfill retaining wall in a stope, comprising: determining the hydrostatic pressure of the backfill slurry when it does not exceed the retaining wall and the additional pressure after it exceeds the retaining wall; calculating the compressive thickness and shear thickness of the retaining wall based on the hydrostatic pressure, and taking the larger of the compressive thickness and the shear thickness as the initial theoretical thickness; constructing a three-dimensional numerical model of the retaining wall based on the initial theoretical thickness, and setting the stress load of the three-dimensional numerical model according to the hydrostatic pressure and the additional pressure; performing a stability simulation on the three-dimensional numerical model to obtain the simulation results of the retaining wall; and iteratively optimizing the initial theoretical thickness based on the simulation results to determine the final retaining wall thickness.

[0005] Furthermore, the hydrostatic pressure ,in, K s For dynamic safety factor, γ 1 represents the bulk density of the filling slurry. h The filling height at one time; the additional pressure ,in, K c The active earth pressure coefficient, q c1 The vertical load is the load that does not exceed the retaining wall. q c2 The vertical load exceeding the retaining wall. c The cohesive force of the filling slurry.

[0006] Furthermore, the distance between the retaining wall and the discharge point of the filling slurry is the first distance, and the dynamic safety factor... K s Positively correlated with the first distance; the vertical load exceeding the retaining wall ,in, b The height of the retaining wall is... H For the height of the ore stope stage, φ The internal friction angle of the filling slurry. k The horizontal coefficient; the active earth pressure coefficient ,in, h 0 represents the equivalent height. , For the breakage angle, , d The distance between the retaining wall and the mining area.

[0007] Furthermore, the compressive thickness ,in, a The width of the retaining wall is... f c The compressive strength of the retaining wall is given by [the relevant parameter]. θ The angle between the supporting surface of the retaining wall and the centerline of the roadway; the shear thickness ,in, f v The shear strength of the retaining wall is given.

[0008] Furthermore, the step of constructing a three-dimensional numerical model of the retaining wall based on the initial theoretical thickness includes: constructing a three-dimensional numerical model containing the surrounding rock and the retaining wall using finite element analysis software based on the geological conditions of the mining area, the dimensions of the roadway, and the initial theoretical thickness; inputting the mechanical parameters of the retaining wall, anchor bars, and anchoring agent into the three-dimensional numerical model; and setting the boundary conditions and initial stress field of the three-dimensional numerical model.

[0009] Furthermore, the mechanical parameters of the retaining wall include a first compressive strength, a first tensile strength, a first shear strength, a first elastic modulus, a first friction coefficient, and a first Poisson's ratio; the mechanical parameters of the anchoring bar include a second yield strength, a second tensile strength, and a second elastic modulus; and the mechanical parameters of the anchoring agent include a third compressive strength, a third elastic modulus, a third cohesion, and a third Poisson's ratio.

[0010] Furthermore, setting the stress load of the three-dimensional numerical model based on the hydrostatic pressure and the additional pressure includes: when the filling slurry does not exceed the retaining wall, the hydrostatic pressure is used as the stress load; when the filling slurry exceeds the retaining wall, the additional pressure is used as the stress load.

[0011] Furthermore, the stability simulation includes simulating displacement distribution, stress distribution, and plastic zone distribution, and the simulation results indicate whether the retaining wall is in a stable or unstable state.

[0012] Further, the step of iteratively optimizing the initial theoretical thickness based on the simulation results to determine the final retaining wall thickness includes: when the simulation result indicates that the retaining wall is in a stable state, gradually reducing the initial theoretical thickness, iteratively constructing the three-dimensional numerical model and performing stability simulations until the simulation result indicates that the retaining wall is in an unstable state, and using the initial theoretical thickness corresponding to the previous generation of the three-dimensional numerical model as the final retaining wall thickness; when the simulation result indicates that the retaining wall is in an unstable state, gradually increasing the initial theoretical thickness, iteratively constructing the three-dimensional numerical model and performing stability simulations until the simulation result indicates that the retaining wall is in a stable state, and using the initial theoretical thickness corresponding to the current three-dimensional numerical model as the final retaining wall thickness.

[0013] A second aspect of this application provides a device for determining the thickness of a backfill retaining wall in a stope, comprising: a pressure determination module configured to determine the hydrostatic pressure of the backfill slurry when it does not exceed the retaining wall and the additional pressure after it exceeds the retaining wall; a thickness calculation module configured to calculate the compressive thickness and shear thickness of the retaining wall based on the hydrostatic pressure, and take the larger of the compressive thickness and the shear thickness as the initial theoretical thickness; a model construction module configured to construct a three-dimensional numerical model of the retaining wall based on the initial theoretical thickness, and set the stress load of the three-dimensional numerical model according to the hydrostatic pressure and the additional pressure; a stability simulation module configured to perform stability simulation on the three-dimensional numerical model to obtain the simulation results of the retaining wall; and a thickness iteration module configured to iteratively optimize the initial theoretical thickness based on the simulation results to determine the final retaining wall thickness.

[0014] A third aspect of this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method for determining the thickness of a mining backfill wall as described in the first aspect above.

[0015] A fourth aspect of this application provides a non-transitory computer-readable storage medium storing computer instructions for causing the computer to perform the method for determining the thickness of a mining backfill wall as described in the first aspect above.

[0016] A fifth aspect of this application provides a computer program product, including computer program instructions that, when executed on a computer, cause the computer to perform the method for determining the thickness of a mining area backfill wall as described in the first aspect above.

[0017] As can be seen from the above, this application provides a method and apparatus for determining the thickness of a backfill retaining wall in a stope. The method includes: determining the hydrostatic pressure of the backfill slurry when it does not exceed the retaining wall and the additional pressure after it exceeds the retaining wall; calculating the compressive thickness and shear thickness of the retaining wall based on the hydrostatic pressure, and taking the larger value of the compressive thickness and shear thickness as the initial theoretical thickness; constructing a three-dimensional numerical model of the retaining wall based on the initial theoretical thickness, and setting the stress load of the three-dimensional numerical model based on the hydrostatic pressure and additional pressure; performing stability simulation on the three-dimensional numerical model to obtain the simulation results of the retaining wall; and iteratively optimizing the initial theoretical thickness based on the simulation results to determine the final thickness of the retaining wall. By analyzing the static effects of hydrostatic pressure and additional pressure on the filling grout, the accuracy of subsequent retaining wall thickness determination is improved. Calculating the compressive and shear thicknesses and using the larger value as the initial theoretical thickness enhances the safety of subsequent retaining wall thickness determination, making the thickness design more comprehensive and reasonable. A three-dimensional numerical model is constructed for stability simulation, simulating the mechanical response of the retaining wall under actual filling loads, verifying the accuracy and reliability of the thickness. Based on the simulation results, the initial theoretical thickness is iteratively optimized to determine the final retaining wall thickness, ensuring the safety and low cost of the retaining wall. Testing shows that this method overcomes the limitations of traditional methods relying on single experiences or simplified theories, achieving good accuracy and safety in determining the retaining wall thickness at a low cost. This method and device for determining the thickness of the stope filling retaining wall is simple, convenient, accurate, and reliable, achieving an optimal balance between structural safety and construction cost. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart illustrating a method for determining the thickness of a backfill wall in a mining area, as described in an embodiment of this application.

[0020] Figure 2 This is a schematic diagram illustrating the logical relationship of a method for determining the thickness of a backfill wall in a mining area, as described in an embodiment of this application.

[0021] Figure 3 This is a schematic diagram of a three-dimensional numerical model in an embodiment of this application.

[0022] Figure 4 This is a structural schematic diagram of the Type II retaining wall in the embodiments of this application.

[0023] Figure 5This is a schematic diagram of the compression model of the Type II retaining wall in the embodiments of this application.

[0024] Figure 6 This is a simulation diagram of the stability of a Class II retaining wall with a thickness of 0.49m in an embodiment of this application.

[0025] Figure 7 This is a simulation diagram of the stability of a Class II retaining wall with a thickness of 0.615m in an embodiment of this application.

[0026] Figure 8 This is a simulation diagram of the stability of a Class II retaining wall with a thickness of 0.74m in an embodiment of this application.

[0027] Figure 9 This is a schematic diagram of a device for determining the thickness of a backfill wall in a mining area, as described in an embodiment of this application.

[0028] Figure 10 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0030] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0031] Currently, the thickness design of retaining walls in high and large mining areas relies heavily on empirical analogies or theoretical calculations. Empirical analogies, based on existing engineering practices, offer advantages such as ease of implementation and quick on-site decision-making under certain conditions. However, in high-level, large-span, and complex slurry characteristics, they can easily lead to overly conservative design results or safety risks. Regarding theoretical calculations, existing methods are mostly based on several idealized assumptions, making it difficult to fully reflect the interaction and long-term bearing capacity between the retaining wall and the surrounding rock and backfill in high and large mining areas. The gap between theoretical models and engineering reality affects the accuracy and reliability of the designed thickness.

[0032] In recent years, numerical simulation technology has been increasingly applied to the stability analysis of retaining walls, with the advantage of simulating the load-bearing process of infill retaining walls. However, in practical design, numerical simulation is often used as a means of later verification or local check, and has not yet formed a closed-loop feedback and iterative optimization mechanism with the earlier theoretical design and engineering decisions. This results in a lack of systematic verification in the design process, making it difficult to achieve the optimal balance between safety, reliability, and economic rationality. Therefore, it is worth considering integrating slurry load analysis, theoretical calculation, and numerical simulation verification to overcome the limitations of traditional methods.

[0033] The following describes specific embodiments in conjunction with... Figures 1 to 10 The technical solution of this application will be described in detail below.

[0034] Some embodiments of this application provide a method for determining the thickness of a stope backfill retaining wall, such as... Figure 1 As shown, it includes the following steps:

[0035] S1. Determine the hydrostatic pressure of the filling slurry when it does not exceed the retaining wall and the additional pressure after it exceeds the retaining wall.

[0036] hydrostatic pressure The unit is kN. K s For dynamic safety factor, γ 1 represents the bulk density of the filling slurry, in kN / m³. 3 , h The filling height is measured in meters (m).

[0037] Additional pressure The unit is kN. K c The active earth pressure coefficient, q c1 This refers to the vertical load that does not exceed the retaining wall, expressed in kPa. q c2 This refers to the vertical load exceeding the retaining wall, expressed in kPa. c This represents the cohesive force of the filling slurry, expressed in kPa.

[0038] The distance between the retaining wall and the discharge point of the filling grout is the first distance, and the dynamic safety factor is... K s It is positively correlated with the first distance. K s A value of 1 to 1.5 can be used. When the distance to the feeding point is close, the slurry has strong fluidity and significant impact, so a larger value should be used; when the distance is far, the slurry tends to be stable, so a smaller value should be used.

[0039] , b The height of the retaining wall is in meters (m). H The height of the stope stage, in meters. φ The internal friction angle of the filling slurry. k This is the horizontal coefficient; ,in, h 0 represents the equivalent height. , The rupture angle is determined by the self-weight of the freely deposited slurry above and the equivalent load after consolidation. This load is transmitted vertically, generating additional thrust on a portion of the retaining wall. Based on Coulomb's theory, assuming the rupture surface is planar, the following condition is met: , d The distance between the retaining wall and the mining area is expressed in meters (m).

[0040] To address the characteristics of the backfilling process in high and large mining areas, two calculation models were established: one for hydrostatic pressure when the backfill slurry does not exceed the height of the retaining wall, and another for additional pressure calculation considering the cohesion of the slurry with a low ash-sand ratio after the slurry exceeds the height of the retaining wall. A dynamic safety factor was introduced in the model based on the distance between the retaining wall and the material feeding point to reflect the difference in the impact of the slurry, thereby constructing a method for determining the retaining wall load suitable for high and large mining areas.

[0041] S2. Calculate the compressive thickness and shear thickness of the retaining wall based on the hydrostatic pressure, and take the larger of the compressive thickness and the shear thickness as the initial theoretical thickness.

[0042] Compressive thickness The unit is mm. a The width of the retaining wall is in meters (m). f c The compressive strength of the retaining wall is expressed in MPa. θ The angle between the supporting surface of the retaining wall and the centerline of the roadway can be determined based on the rock strength coefficient f. When f < 6... θ When the angle is 20° and f > 6, θ Take 30°.

[0043] Shear thickness The unit is mm. f v This represents the shear strength of the retaining wall, expressed in MPa.

[0044] Initial theoretical thickness The unit is mm. Based on the mechanical properties of the retaining wall, the thickness is calculated from both compressive and shear strength aspects. Finally, the maximum value of the two calculation results is taken as the initial theoretical thickness of the retaining wall.

[0045] S3. Construct a three-dimensional numerical model of the retaining wall based on the initial theoretical thickness, and set the stress load of the three-dimensional numerical model according to the hydrostatic pressure and the additional pressure.

[0046] Based on the geological conditions of the mining area (obtainable from geological data), the tunnel dimensions (obtainable from design drawings), and the initial theoretical thickness, a three-dimensional numerical model including the surrounding rock and retaining wall is constructed using finite element analysis software. The mechanical parameters of the retaining wall, anchor bars, and anchoring agent are input into the three-dimensional numerical model. Boundary conditions and the initial stress field of the three-dimensional numerical model are then set. When the filling grout does not exceed the retaining wall, hydrostatic pressure is used as the load; when the filling grout exceeds the retaining wall, additional pressure is used as the load.

[0047] The mechanical parameters of the retaining wall include the first compressive strength, the first tensile strength, the first shear strength, the first elastic modulus, the first friction coefficient, and the first Poisson's ratio; the mechanical parameters of the anchoring bar include the second yield strength, the second tensile strength, and the second elastic modulus; and the mechanical parameters of the anchoring agent include the third compressive strength, the third elastic modulus, the third cohesion, and the third Poisson's ratio.

[0048] Specifically, a three-dimensional numerical model containing the surrounding rock and the infill retaining wall can be constructed using Midas GTS NX software, and the model can be meshed. The three-dimensional mesh model constructed in Midas GTS NX is then imported into FLAC 3D simulation software. In FLAC 3D, a material constitutive model is defined, and the surrounding rock and the retaining wall are assigned the corresponding mechanical parameters. Boundary constraints and initial stress fields of the model are set, and pressure boundary conditions acting on the retaining wall are set according to hydrostatic pressure and additional pressure.

[0049] S4. Perform stability simulation on the three-dimensional numerical model to obtain the simulation results of the retaining wall.

[0050] The filling process is simulated by applying slurry loads step by step and calculating the stress, strain and displacement of the retaining wall during the filling process. After the simulation, the stress distribution cloud map, displacement vector map and plastic zone development of the retaining wall are extracted and analyzed to evaluate its overall stability under compression and obtain the simulation results. The simulation results include whether the retaining wall is in a stable or unstable state.

[0051] S5. Based on the simulation results, iteratively optimize the initial theoretical thickness to determine the final retaining wall thickness.

[0052] like Figure 2As shown, when the simulation result indicates that the retaining wall is in a stable state, the initial theoretical thickness is gradually reduced (e.g., by 10mm, 50mm, or 100mm each time), and the three-dimensional numerical model is iteratively constructed and stability simulation is performed until the simulation result indicates that the retaining wall is in an unstable state. The initial theoretical thickness corresponding to the previous generation three-dimensional numerical model is then used as the final retaining wall thickness. When the simulation result indicates that the retaining wall is in an unstable state, the initial theoretical thickness is gradually increased (e.g., by 10mm, 50mm, or 100mm each time), and the three-dimensional numerical model is iteratively constructed and stability simulation is performed until the simulation result indicates that the retaining wall is in a stable state. The initial theoretical thickness corresponding to the current three-dimensional numerical model is then used as the final retaining wall thickness.

[0053] A three-dimensional numerical model was established, and the theoretical calculation results were used as initial values ​​for stability simulation. The stress, strain and displacement response of the retaining wall under the filling load were analyzed by simulation, and the theoretical thickness was iteratively optimized and verified. Finally, the optimal retaining wall thickness was determined by combining the theoretical calculation and numerical simulation results to ensure safety and stability.

[0054] This method for determining the thickness of retaining walls in stopes organically combines staged slurry load analysis, multi-criteria theoretical calculations, and numerical simulation verification, forming a complete and closed-loop design process. It overcomes the limitations of traditional methods that rely on single experiences or simplified theories, providing a theoretical basis for the thickness design of retaining walls in tall stopes.

[0055] This method innovatively introduces a multi-criteria verification mechanism into theoretical calculations, simultaneously considering the compressive and shear stability of the retaining wall, ensuring the overall safety of the retaining wall under complex loads. It overcomes the shortcomings of traditional designs that often focus on a single failure mode, making thickness design more comprehensive and rational.

[0056] This method deeply integrates numerical simulation into the design process and establishes a verification method that can be iteratively optimized. By simulating the mechanical response of the retaining wall under actual filling loads, the theoretical calculation results can be effectively corrected and optimized, significantly improving the accuracy of thickness determination and engineering reliability.

[0057] This method establishes a complete technical system encompassing analysis, calculation, verification, and decision-making. Based on the retaining wall thickness determined by this method, an optimal balance between structural safety and construction economy can be achieved while fully ensuring the safety of backfilling operations in high-altitude mining areas. This method possesses significant engineering application value and economic benefits.

[0058] Example 1 mining background A certain iron mine adopts the staged drilling and subsequent backfilling mining method. The stope has a size of 45m×18m×60m. The bottom 0m to 6m and 55m to 60m are backfilled with slurry with a lime-sand ratio of 1:4. The first step from 6m to 55m is backfilled with slurry with a ratio of 1:8, and the second step is backfilled with slurry with a ratio of 1:20.

[0059] Based on the actual situation, the iron mine currently has three types of retaining walls: Type I retaining walls measure 5.6m × 5.6m, Type II retaining walls measure 6.5m × 6.5m, and Type III retaining walls measure 7.8m × 7.8m. All three types of retaining walls are constructed using MU25 red bricks, with brick dimensions of 240mm × 115mm × 55mm, and M10 mortar is used. Figure 4 As shown, 10 sets of anchor bars are arranged around the retaining wall, including 3 anchor bars at the top of the arch, 4 sets of anchor bars on both sides, and 3 anchor bars at the bottom. The anchor bars are 0.5m deep, 0.5m exposed, and 20mm in diameter. The transverse tie bars inside the wall are at the same height and position as the anchor bars on both sides, with 4 bars per layer and a diameter of 8mm. Two reinforcing wall columns are built on the outside of the retaining wall, with dimensions of 0.5m × 0.5m and a height of 3m, and are evenly distributed according to the width of the retaining wall. Since the position of the roadway brow line has been damaged, the retaining wall is moved outward by 5m according to the on-site construction situation. At the same time, concrete spraying has been carried out around the roadway before the construction of the retaining wall.

[0060] Retaining wall stress calculation A certain iron mine has a single filling height of 1.5m and a slurry bulk density of 19kN / m³. 3 Based on the distance between the filling retaining wall and the material discharge point, safety factors are taken as 1.4 and 1 respectively; Calculate the hydrostatic pressure on the slurry when it does not exceed the retaining wall.

[0061] but , , In the formula , These represent the static load pressure values ​​of the retaining walls near and far from the material discharge point, respectively.

[0062] When the slurry height exceeds the retaining wall, the vertical load exceeding the retaining wall height is adopted. The calculations are as follows: the stope stage height is 60m, the internal friction angle of the filling slurry is 33°, and the lateral coefficient is taken as 0.83.

[0063] but .

[0064] use Calculate its equivalent height h 0.

[0065] but .

[0066] use Calculate its fracture angle. Based on the site conditions, the distance from the retaining wall to the mining area is 5m.

[0067] but , .

[0068] use Calculate its active earth pressure coefficient.

[0069] but .

[0070] From a structural safety perspective, the lateral pressure of the upper and middle slurry on the retaining wall is calculated uniformly based on the cohesion corresponding to the middle mortar ratio with the lowest cohesion. In the first step, the middle mortar ratio is 1:8, and the cohesion is taken as 200 kPa; in the second step, the middle mortar ratio is 1:20, and the cohesion is taken as 90 kPa. The formula is used... Calculate the static pressure load values ​​of the filling grout in the first and second steps on the retaining wall.

[0071] but ; ; ; ; In the formula , , , These represent the static load pressure values ​​of the retaining wall when the first step is close to the material discharge point, the first step is far from the material discharge point, the second step is close to the material discharge point, and the second step is far from the material discharge point, respectively.

[0072] The results show that when the cement-sand ratio is 1:8, the static pressure of the filling grout on the retaining wall is negative, indicating that the cohesion of this section of grout is sufficient to offset its own static pressure after exceeding the height of the retaining wall. Therefore, it can be considered that no additional static pressure is applied to the retaining wall, i.e., the actual static pressure is zero. When the cement-sand ratio is 1:20, the pressure values ​​are all positive, indicating that the grout will apply additional static pressure to the structure after exceeding the top of the retaining wall.

[0073] Calculation of initial theoretical thickness of retaining wall The retaining walls are 5.6m × 5.6m for Class I, 6.5m × 6.5m for Class II, and 7.8m × 7.8m for Class III. They are constructed using MU25 red bricks with dimensions of 240mm × 115mm × 55mm, using M10 mortar. For masonry structures cured for 28 days according to the "Code for Design of Masonry Structures" (GB50003-2011), the design compressive strength is 2.98MPa and the design shear strength is 0.17MPa. The surrounding rock strength coefficient is greater than 6. θ A 30° angle is used. Based on the location of the retaining walls on site, Class I retaining walls are constructed only at locations closest to the material unloading point, Class III retaining walls are constructed only at locations furthest from the material unloading point, while Class II retaining walls are constructed at both locations near and far from the material unloading point. [The following is a separate, unrelated sentence:] Adopting... , , The preliminary design thicknesses for the three types of retaining walls were determined.

[0074] but ; ; ; ; In the formula: , , , These represent the thicknesses of Class I retaining walls at a pressure of 39.9 kPa, Class II retaining walls at a pressure of 39.9 kPa, Class II retaining walls at a pressure of 28.5 kPa, and Class III retaining walls at a pressure of 28.5 kPa, respectively.

[0075] Calculated ; ; ; .

[0076] Since MU25 red bricks are used for construction, and the dimensions of MU25 red bricks are 240mm×115mm×55mm, and 10mm of mortar needs to be applied between the brick joints, the actual construction is carried out according to 365mm, 490mm, 615mm and 740mm. Therefore, the initial theoretical thickness is obtained by rounding based on the actual situation.

[0077] but ; ; ; .

[0078] Constructing a three-dimensional numerical model A numerical model of the infill retaining wall was constructed based on the actual site conditions. The model's exterior is the surrounding rock, and the middle is the retaining wall. The model dimensions are 40m × 12.6m × 30m. Three-dimensional infill retaining wall models were constructed based on the dimensions of three types of retaining walls. Since the retaining wall is displaced 5m inwards into the roadway, it was positioned 5m from the model boundary. Furthermore, according to the design and arrangement of the anchor bars and transverse tie bars, corresponding anchor bars and transverse tie bars were added to the model. During the mesh generation process, the infill retaining wall area was finely divided. The software involved in this embodiment includes, but is not limited to, Midas GTS NX and FLAC 3D. Figure 3 This is a schematic diagram of the model obtained in this embodiment. Figure 4 This is a schematic diagram of the Class II retaining wall structure obtained in this embodiment. In the process of constructing the numerical model, the surrounding rock and the retaining wall are regarded as homogeneous and isotropic media. Therefore, the constitutive model of the retaining wall and the surrounding rock is set as the Mohr-Coulomb model.

[0079] After the model is constructed, material model parameters need to be set. The material model parameters of the retaining wall are obtained according to the "Code for Design of Masonry Structures" (GB 50003-2011), the material model parameters of the anchor bars and transverse tie bars are obtained according to the "Standard for Design of Concrete Structures" (GB / T50010-2010), and the material model parameters of the anchoring agent are obtained according to the "Factory Inspection Report" issued by the manufacturer. Table 1 shows the material model parameters of the retaining wall obtained in this embodiment, Table 2 shows the material model parameters of the anchor bars obtained in this embodiment 1, and Table 3 shows the material model parameters of the anchoring agent obtained in this embodiment 1.

[0080] Table 1 Mechanical parameters of the retaining wall

[0081] Table 2 Mechanical parameters of anchor bars

[0082] Table 3 Mechanical parameters of anchoring agent

[0083] After setting the material model parameters, boundary conditions need to be set for the model. Set horizontal stress constraints in the Y direction on the front and back boundaries of the model, set horizontal stress constraints in the X direction on the left and right sides, and set full displacement constraints in the X, Y, and Z directions on the bottom boundary of the model.

[0084] The pressure process of the retaining wall was designed. According to theoretical calculations, when the first step uses a 1:8 filling grout, the retaining wall does not experience additional static pressure after the grout exceeds its height. However, when the second step uses a 1:20 filling grout, the retaining wall experiences additional static pressure after the grout exceeds its height. Therefore, when the first step uses a 1:8 filling grout, the retaining wall is only subjected to hydrostatic pressure. Without considering the static pressure generated by the slurry exceeding the retaining wall; when the second step uses a 1:20 filling slurry for filling, the retaining wall is subjected to hydrostatic pressure. In addition, it is also subject to the additional pressure generated by the slurry exceeding the retaining wall. The specific stress conditions of the retaining wall are as follows: Figure 5 As shown in the diagram, the five retaining walls on the left are where the slurry pressure does not exceed the hydrostatic pressure exerted on the retaining walls. The rightmost retaining wall represents the additional pressure exerted by the slurry exceeding the retaining wall's capacity. .

[0085] Stability simulation Numerical simulations were performed based on the above model settings to obtain the displacement, stress, and plastic zone distribution of the retaining wall. By analyzing the displacement, stress, and plastic zone distribution, the analysis results of the displacement, stress, and plastic zone distribution were obtained. Figures 6 to 8 The following is a partial simulation diagram obtained in this embodiment, wherein... Figure 6 This is a cloud map showing the distribution of displacement and stress-plastic zone of a Class II retaining wall with a thickness of 0.49m, located close to the material unloading point. Figure 7 This is a cloud map showing the displacement and stress-plastic zone distribution of a Class II filled retaining wall with a thickness of 0.615m located close to the material unloading point. Figure 8 The image shows the distribution cloud map of displacement and stress-plastic zone of a Class II filling retaining wall with a thickness of 0.74m that is close to the material feeding point in the second step.

[0086] Simulation results and iterative optimization Type I backfill retaining wall: The maximum displacement of the Type I backfill retaining wall with a thickness of 365mm occurred after three backfilling operations, with a maximum value of 0.736mm and a maximum stress of 1.2MPa, indicating large-scale plastic failure. This indicates that the retaining wall was in an unstable state at this time. A second simulation was conducted by increasing the thickness to 490mm. The results of the second simulation showed that after increasing the thickness to 490mm, the maximum displacement of the retaining wall still occurred after three backfilling operations, but the maximum displacement was 0.264mm and the maximum stress was 1.03MPa. The retaining wall only showed small-scale plastic failure, indicating that the retaining wall was in a stable state at this time. Therefore, the thickness of the Type I backfill retaining wall should be 490mm during the first-stage mining.

[0087] After the two-stage stope filling was completed, the 490mm thick Class I backfill retaining wall, under additional static pressure, exhibited a maximum displacement of 0.808mm and a maximum stress of 1.01MPa, indicating large-scale plastic failure. This suggests that the retaining wall was in an unstable state at this point. A second simulation was conducted with the thickness increased to 615mm. The results showed that with the thickness increased to 615mm, the maximum displacement was 0.481mm and the maximum stress was 0.881MPa. The retaining wall only experienced small-scale plastic failure, indicating that it was in a stable state at this point. Therefore, the thickness of the Class I backfill retaining wall during the two-stage mining should be 615mm.

[0088] Type II backfill retaining wall: The maximum displacement of the Type II backfill retaining wall, which is close to the material discharge point and has a thickness of 490mm, occurs after three backfilling operations, with a maximum value of 0.565mm and a maximum stress of 1.02MPa. Large-scale plastic failure occurs, indicating that the retaining wall is in an unstable state at this time. A second simulation was conducted to increase the thickness of the retaining wall at this location to 615mm. The results of the second simulation show that after increasing the thickness to 615mm, the maximum displacement of the retaining wall still occurs after three backfilling operations, but the maximum displacement is 0.271mm and the maximum stress is 0.991MPa. The retaining wall only shows small-scale plastic failure, indicating that the retaining wall is in a stable state at this time. Therefore, the thickness of the Type II backfill retaining wall close to the material discharge point during the first-stage mining should be 615mm.

[0089] After the second-stage stope filling was completed, the 615mm thick filling retaining wall near the material unloading point exhibited a maximum displacement of 0.562mm and a maximum stress of 0.908MPa under static pressure, indicating large-scale plastic failure and instability. A second simulation was then conducted with the retaining wall thickness increased to 740mm. The results showed that with the thickness increased to 740mm, the maximum displacement was 0.424mm and the maximum stress was 0.748MPa, with only minor plastic failure, indicating a stable state. Therefore, the thickness of the Class II filling retaining wall near the material unloading point during the second-stage mining process should be 740mm.

[0090] The maximum displacement of the 365mm thick Class II backfill retaining wall, located far from the material discharge point, occurred after three backfilling operations, with a maximum displacement of 1.22mm and a maximum stress of 0.908MPa, indicating large-scale plastic failure and instability. A second simulation was conducted at this location, increasing the wall thickness to 490mm. The results showed that while the maximum displacement still occurred after three backfilling operations, the maximum displacement was 0.406mm and the maximum stress was 0.356MPa, indicating only small-scale plastic failure and stability. Therefore, the thickness of the Class II backfill retaining wall, located far from the material discharge point, should be 490mm during the first-stage mining phase.

[0091] After the second-stage stope filling, the 490mm thick filling retaining wall, located far from the discharge point, exhibited a maximum displacement of 0.936mm and a maximum stress of 1.02MPa under static pressure, indicating large-scale plastic failure. This suggests that the retaining wall was in an unstable state. A second simulation was conducted with the thickness increased to 615mm. The results showed that with the thickness increased to 615mm, the maximum displacement was 0.529mm and the maximum stress was 0.99MPa. The retaining wall only experienced small-scale plastic failure, indicating that it was in a stable state. Therefore, the thickness of the Class II filling retaining wall, located far from the discharge point, should be 615mm during the second-stage mining process.

[0092] For Class III infill retaining walls with a thickness of 365mm, the maximum displacement occurs after three filling operations, with a maximum value of 1.99mm and a maximum stress of 0.638MPa, indicating large-scale plastic failure and instability. A second simulation was conducted with the thickness increased to 490mm. The results showed that the maximum displacement still occurred after three filling operations, with a maximum displacement of 0.872mm and a maximum stress of 0.869MPa, indicating continued instability. A third simulation was conducted with the thickness increased to 615mm. While the maximum displacement still occurred after three filling operations, the maximum displacement was 0.432mm and the maximum stress was 0.817MPa, indicating only small-scale plastic failure and stability. Therefore, the thickness of Class III infill retaining walls should be 615mm.

[0093] After the two-stage stope filling was completed, the 615mm thick Class III backfill retaining wall, under additional static pressure, exhibited a maximum displacement of 0.73mm and a maximum stress of 0.816MPa, indicating large-scale plastic failure. This suggests that the retaining wall was in an unstable state at this point. A second simulation was conducted with the thickness increased to 740mm. The results showed that with the thickness increased to 740mm, the maximum displacement was 0.572mm and the maximum stress was 0.688MPa. The retaining wall only experienced small-scale plastic failure, indicating that it was in a stable state at this point. Therefore, the thickness of the Class III backfill retaining wall during the two-stage mining should be 740mm.

[0094] Based on the thickness determined by the above method, the mine has implemented on-site industrial application since October 2025. The constructed retaining walls have not been damaged during the filling process, demonstrating good safety and low cost.

[0095] It is understood that before using the technical solutions of the various embodiments in this disclosure, users will be informed of the type, scope of use, and usage scenarios of the personal information involved in an appropriate manner, and user authorization will be obtained.

[0096] For example, upon receiving a user's active request, a prompt message is sent to the user to explicitly inform them that the requested operation will require the acquisition and use of the user's personal information. This allows the user to independently choose, based on the prompt message, whether to provide personal information to the software or hardware such as electronic devices, applications, servers, or storage media performing the operations of this disclosed technical solution.

[0097] As an optional but not limited implementation, in response to a user's active request, sending a prompt message to the user can be done via a pop-up window, where the prompt message can be presented in text format. Furthermore, the pop-up window can also include a selection control allowing the user to choose "agree" or "disagree" to provide personal information to the electronic device.

[0098] It is understood that the above notification and user authorization process are merely illustrative and do not constitute a limitation on the implementation of this disclosure. Other methods that comply with relevant laws and regulations may also be applied to the implementation of this disclosure.

[0099] In some embodiments of this application, a device for determining the thickness of the stope filling retaining wall is provided, such as... Figure 9 As shown, the system includes: a pressure determination module 91, configured to determine the hydrostatic pressure when the filling grout does not exceed the retaining wall and the additional pressure after exceeding the retaining wall; a thickness calculation module 92, configured to calculate the compressive thickness and shear thickness of the retaining wall based on the hydrostatic pressure, and take the larger of the compressive thickness and the shear thickness as the initial theoretical thickness; a model construction module 93, configured to construct a three-dimensional numerical model of the retaining wall based on the initial theoretical thickness, and set the stress load of the three-dimensional numerical model according to the hydrostatic pressure and the additional pressure; a stability simulation module 94, configured to perform stability simulation on the three-dimensional numerical model to obtain the simulation results of the retaining wall; and a thickness iteration module 95, configured to iteratively optimize the initial theoretical thickness based on the simulation results to determine the final retaining wall thickness.

[0100] The apparatus described above is used to implement the corresponding method for determining the thickness of the backfill wall in the mining area in any of the foregoing embodiments, and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0101] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the method for determining the thickness of the mining area backfill wall as described in any of the above embodiments.

[0102] Figure 10This embodiment illustrates a more specific hardware structure of an electronic device, which may include a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, memory 1020, input / output interface 1030, and communication interface 1040 are interconnected internally via the bus 1050.

[0103] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0104] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0105] The input / output interface 1030 is used to connect input / output modules to realize information input and output. The input / output modules can be configured as components within the device (not shown in the figure) or externally connected to the device to provide corresponding functions. The input devices can include keyboards, mice, touchscreens, microphones, various sensors, etc., and the output devices can include displays, speakers, vibrators, indicator lights, etc.

[0106] The communication interface 1040 is used to connect a communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (e.g., USB, Ethernet cable, etc.) or wireless means (e.g., mobile network, WIFI, Bluetooth, etc.).

[0107] Bus 1050 includes a pathway for transmitting information between various components of the device, such as processor 1010, memory 1020, input / output interface 1030, and communication interface 1040.

[0108] It should be noted that although the above-described device only shows the processor 1010, memory 1020, input / output interface 1030, communication interface 1040, and bus 1050, in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0109] The electronic devices described above are used to implement the corresponding method for determining the thickness of the backfill wall in the mining area in any of the foregoing embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0110] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides a non-transitory computer-readable storage medium storing computer instructions for causing the computer to execute the method for determining the thickness of the mining area backfill wall as described in any of the above embodiments.

[0111] The non-transitory computer-readable medium of this embodiment includes both permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0112] The computer instructions stored in the storage medium of the above embodiments are used to cause the computer to execute the method for determining the thickness of the backfill wall in the mining area as described in any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0113] Based on the same concept, corresponding to the methods of any of the above embodiments, this application also provides a computer program product, including computer program instructions. When the computer program instructions are run on a computer, the computer causes the computer to execute the method for determining the thickness of the backfill wall in the mining area as described in any of the above embodiments, which has the beneficial effects of the corresponding method embodiments, and will not be repeated here.

[0114] Furthermore, to simplify the description and discussion, and to avoid obscuring the embodiments of this application, the apparatus may be shown in block diagram form. This is to prevent the embodiments of this application from being difficult to understand, and it also takes into account the fact that the details of the implementation of these block diagram apparatuses are highly dependent on the platform on which the embodiments of this application will be implemented (i.e., these details should be fully within the understanding of those skilled in the art). In setting forth specific details to describe exemplary embodiments of this application, it will be apparent to those skilled in the art that the embodiments of this application may be implemented without these specific details or with variations thereof. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0115] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0116] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A method for determining the thickness of a retaining wall used for backfilling in a stope, characterized in that, include: Determine the hydrostatic pressure of the filling slurry when it does not exceed the retaining wall and the additional pressure after it exceeds the retaining wall; The compressive thickness and shear thickness of the retaining wall are calculated based on the hydrostatic pressure, and the larger of the compressive thickness and the shear thickness is taken as the initial theoretical thickness. A three-dimensional numerical model of the retaining wall is constructed based on the initial theoretical thickness, and the stress load of the three-dimensional numerical model is set according to the hydrostatic pressure and the additional pressure. The stability of the three-dimensional numerical model is simulated to obtain the simulation results of the retaining wall; The final retaining wall thickness is determined by iteratively optimizing the initial theoretical thickness based on the simulation results.

2. The method for determining the thickness of the retaining wall for stope filling according to claim 1, characterized in that, The hydrostatic pressure ,in, K s For dynamic safety factor, γ 1 represents the bulk density of the filling slurry. h This refers to the height of a single filling operation. The additional pressure ,in, K c The active earth pressure coefficient, q c1 The vertical load is the load that does not exceed the retaining wall. q c2 The vertical load exceeding the retaining wall. c The cohesive force of the filling slurry.

3. The method for determining the thickness of the retaining wall for mine filling according to claim 2, characterized in that, The distance between the retaining wall and the discharge point of the filling slurry is the first distance, and the dynamic safety factor is... K s It is positively correlated with the first distance; The vertical load exceeding the retaining wall ,in, b The height of the retaining wall is... H For the height of the ore stope stage, φ The internal friction angle of the filling slurry. k This is the horizontal coefficient; The active earth pressure coefficient ,in, h 0 represents the equivalent height. , For the breakage angle, , d The distance between the retaining wall and the mining area.

4. The method for determining the thickness of the retaining wall for mine filling according to claim 3, characterized in that, The compressive thickness ,in, a The width of the retaining wall is... f c The compressive strength of the retaining wall is given by [the relevant parameter]. θ The angle between the supporting surface of the retaining wall and the centerline of the roadway; The shear thickness ,in, f v The shear strength of the retaining wall is given.

5. The method for determining the thickness of the retaining wall for mine filling according to claim 1, characterized in that, The construction of the three-dimensional numerical model of the retaining wall based on the initial theoretical thickness includes: Based on the geological conditions of the mining area, the dimensions of the roadway, and the initial theoretical thickness, a three-dimensional numerical model including the surrounding rock and the retaining wall was constructed using finite element analysis software. Input the mechanical parameters of the retaining wall, anchor bars, and anchoring agent into the three-dimensional numerical model; Define the boundary conditions and initial stress field of the three-dimensional numerical model.

6. The method for determining the thickness of the retaining wall for mine filling according to claim 5, characterized in that, The mechanical parameters of the retaining wall include a first compressive strength, a first tensile strength, a first shear strength, a first elastic modulus, a first coefficient of friction, and a first Poisson's ratio; The mechanical parameters of the anchor bar include the second yield strength, the second tensile strength, and the second elastic modulus. The mechanical parameters of the anchoring agent include the third compressive strength, the third elastic modulus, the third cohesion, and the third Poisson's ratio.

7. The method for determining the thickness of the retaining wall for mine filling according to claim 1, characterized in that, The method of setting the stress load of the three-dimensional numerical model based on the hydrostatic pressure and the additional pressure includes: when the filling slurry does not exceed the retaining wall, the hydrostatic pressure is used as the stress load; when the filling slurry exceeds the retaining wall, the additional pressure is used as the stress load.

8. The method for determining the thickness of the retaining wall for stope filling according to claim 1, characterized in that, The stability simulation includes simulating displacement distribution, stress distribution, and plastic zone distribution. The simulation results indicate whether the retaining wall is in a stable or unstable state.

9. The method for determining the thickness of the retaining wall for backfilling in a stope according to claim 1, characterized in that, The step of iteratively optimizing the initial theoretical thickness based on the simulation results to determine the final retaining wall thickness includes: When the simulation result indicates that the retaining wall is in a stable state, the initial theoretical thickness is gradually reduced, the three-dimensional numerical model is iteratively constructed and stability simulation is performed until the simulation result indicates that the retaining wall is in an unstable state. The initial theoretical thickness corresponding to the previous generation of the three-dimensional numerical model is then used as the final retaining wall thickness. When the simulation result indicates that the retaining wall is in an unstable state, the initial theoretical thickness is gradually increased, the three-dimensional numerical model is iteratively constructed and stability simulation is performed until the simulation result indicates that the retaining wall is in a stable state. The initial theoretical thickness corresponding to the current three-dimensional numerical model is then used as the final retaining wall thickness.

10. A device for determining the thickness of a retaining wall used for backfilling in a mining area, characterized in that, include: The pressure determination module is configured to determine the hydrostatic pressure of the filling slurry when it does not exceed the retaining wall and the additional pressure after it exceeds the retaining wall. The thickness calculation module is configured to calculate the compressive thickness and shear thickness of the retaining wall based on the hydrostatic pressure, and take the larger value of the compressive thickness and the shear thickness as the initial theoretical thickness. The model building module is configured to build a three-dimensional numerical model of the retaining wall based on the initial theoretical thickness, and to set the stress load of the three-dimensional numerical model according to the hydrostatic pressure and the additional pressure. The stability simulation module is configured to perform stability simulation on the three-dimensional numerical model to obtain the simulation results of the retaining wall; The thickness iteration module is configured to iteratively optimize the initial theoretical thickness based on the simulation results to determine the final retaining wall thickness.

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