A numerical simulation based step-by-step mining method for underground deposits

Abstract

The application relates to the technical field of mine exploitation engineering, and discloses a step-by-step underground deposit mining method based on numerical simulation, which comprises the following steps: a plurality of panels are divided along the ore body trend at intervals, and a stope and a pillar stope are divided in the plurality of panels at intervals along the direction perpendicular to the ore body trend; a one-step stope is mined; after the one-step stope is completed, a blast hole size set used for simulation is preselected; ore body attribute parameters representing the rock firmness coefficient and the joint fissure development degree are obtained, and two-step pillar mining constraint conditions are determined; according to the blast hole size set, a preset simplified blasting simulation model is adopted, the two-step pillar mining constraint conditions are combined, and a target blast hole size is output; and the two-step pillar mining is guided based on the target blast hole size. The application has the effects of improving the blasting effect and improving the two-step deposit mining stability under the premise of ensuring the model calculation efficiency.

Description

Technical Field

[0001] This application relates to the field of mining engineering technology, and in particular to a step-by-step mining method for underground ore deposits based on numerical simulation. Background Technology

[0002] Blasting technology is a key engineering method for the recovery of underground mineral deposits. However, the intense vibrations generated by blasting are a significant cause of damage, cracking, and even collapse of the backfill. When underground mineral deposits are recovered in stages using large-diameter deep-hole mines, the blasting of the first mining stop is relatively free. However, the blasting of the later mining pillars requires consideration of protecting the final boundary and surrounding facilities before adopting blasting technology, as voids have already formed around them. Therefore, it is essential to conduct optimization studies on blasting parameters for mining using numerical simulation methods.

[0003] Existing numerical simulation methods for underground mine blasting processes simplify the blast load into a time-varying nodal force applied to the structure. While this method is highly efficient, it neglects the rapid changes in time and space during the blasting process and the complexity of the process itself. This makes it difficult to accurately describe the blasting simulation model, resulting in poor accuracy in the calculation of blast hole parameters, which affects the blasting effect and the stability of mine recovery.

[0004] Regarding the aforementioned technologies, the inventors discovered that existing numerical simulation methods for underground blasting processes suffer from a contradiction between model efficiency and accuracy, affecting blasting effectiveness and the stability of ore mining. Summary of the Invention

[0005] To improve blasting effectiveness and enhance the stability of ore deposit mining, this application provides a step-by-step mining method for underground ore deposits based on numerical simulation.

[0006] Firstly, this application provides a method for step-by-step mining of underground mineral deposits based on numerical simulation.

[0007] This application is achieved through the following technical solution:

[0008] A step-by-step mining method for underground mineral deposits based on numerical simulation includes the following steps: The ore body is divided into several panels at intervals along its strike, and within these panels, stopes and pillars are divided at intervals perpendicular to the strike of the ore body. One-step stope recovery; After the first-stage stope mining is completed, a set of borehole sizes is pre-selected for simulation. Obtain orebody property parameters that characterize the rock firmness coefficient and the degree of joint and fracture development, and determine the constraints for two-step pillar mining. Based on the set of borehole sizes, a preset simplified blasting simulation model is used, combined with the two-step pillar mining constraints, to output the target borehole size. Based on the target borehole size, the two-step pillar recovery is guided.

[0009] In a preferred embodiment, this application can be further configured such that: the step of obtaining orebody property parameters characterizing the rock firmness coefficient and the degree of joint and fracture development, and determining the constraints for two-step pillar mining, includes: After the first-step stope mining is completed, the rock mass structure grade and structural surface condition grade of the preset target measuring points are obtained, and the geological strength value of the target measuring points is determined. The primary joint occurrence and secondary joint occurrence generated by the first-step stope mining of the preset target area are obtained, wherein the target measuring point is located in the target area; Based on the primary joint orientation and the secondary joint orientation, a pole map or joint distribution cloud map is generated to determine the dominant joint group in the target survey area; Based on the two-step pillar mining conditions, preset geological strength thresholds and dominant joint set thresholds are established. Based on the geological strength threshold and the dominant joint group threshold, a set of target survey areas and target survey points that meet the requirements are used as the constraint conditions for the two-step pillar mining.

[0010] In a preferred embodiment, this application can be further configured such that the steps for constructing the simplified blasting simulation model include: Obtain the type of the main model; If the main body of the model is rock, the main body of the model is divided into Lagrange finite element meshes, and the Lagrange algorithm is used for modeling to obtain the first simulation model; If the main body of the model is an explosive, the main body of the model is divided into Eulerian finite element meshes, and the ALE algorithm is used for modeling to obtain the second simulation model; By coupling the first simulation model and the second simulation model, the simplified blasting simulation model is obtained.

[0011] In a preferred embodiment, this application can be further configured as follows: the step of outputting the target borehole size based on the borehole size set, using a preset simplified blasting simulation model, and combining the two-step pillar mining constraints, includes... Initialize the simplified blasting simulation model; The dimensions of each borehole in the borehole size set are sequentially input into the simplified blasting simulation model, different row spacing and hole spacing are matched, and the holes are laid out and blasted in the manner of equal row spacing and hole spacing to obtain simulation results. Among them, the hole layout method selects two rows of blasting holes, and two boreholes are preset in each row for detonation. Based on the simulation results, the optimal row spacing and hole spacing for each borehole size are determined; Based on the constraints of the two-step pillar mining, the target borehole size is determined and output.

[0012] In a preferred embodiment, this application can be further configured such that the blasting method is that two preset blast holes in each row are detonated sequentially at millisecond intervals.

[0013] In a preferred embodiment, this application can be further configured such that the step of determining the optimal row spacing and hole spacing for each borehole size based on the simulation results includes, Detect the simulation results; When the simulation result shows that no triangular spine appears in either of the two preset boreholes in each row, the currently matched row spacing and borehole spacing are increased by a preset threshold to be the optimal row spacing and borehole spacing for the current borehole size.

[0014] Secondly, this application provides a device for optimizing blast holes.

[0015] This application is achieved through the following technical solution: A blasting hole optimization device, applied to any of the above-mentioned step-by-step mining methods for underground deposits based on numerical simulation, includes, The borehole pre-selection module is used to pre-select a set of borehole sizes for simulation after the completion of the first-step stope mining. The constraint module is used to obtain orebody property parameters that characterize the rock firmness coefficient and the degree of joint and fracture development, and to determine the constraint conditions for the two-step pillar mining. The optimization module is used to output the target borehole size based on the borehole size set, using a preset simplified blasting simulation model, combined with the two-step pillar mining constraints.

[0016] Thirdly, this application provides a computer device.

[0017] This application is achieved through the following technical solution: A computer device includes 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 steps of any of the above-described numerical simulation-based step-by-step mining methods for underground deposits.

[0018] Fourthly, this application provides a computer-readable storage medium.

[0019] This application is achieved through the following technical solution: A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of any of the above-described numerical simulation-based step-by-step mining methods for underground deposits.

[0020] Fifthly, this application provides a computer program product.

[0021] This application is achieved through the following technical solution: A computer program product includes a computer program that, when executed by a processor, implements the steps of any of the above-described numerical simulation-based step-by-step mining methods for underground deposits.

[0022] In summary, compared with the prior art, the beneficial effects of the technical solution provided in this application include at least the following: The ore body was divided into several panels at intervals along its strike, and within these panels, stopes and pillars were further divided at intervals perpendicular to the strike. The underground deposit was then mined in stages through these individual mining units, achieving efficient and stable mining. After the first stage of stope mining, a set of borehole sizes was pre-selected for simulation to pre-determine blasting parameters suitable for the second stage of pillar mining, improving the efficiency of subsequent blasting parameter optimization. Ore body property parameters characterizing rock firmness and joint development were obtained to determine the constraints for the second stage of pillar mining. This allows for blasting parameter optimization while effectively controlling blasting vibration and damage range and maintaining surrounding rock stability, ensuring good blasting results. Based on the borehole sizes… The Cunji model employs a pre-defined simplified blasting simulation model, combined with the constraints of two-step pillar mining, to output target blast hole sizes and guide the two-step pillar mining process. By simplifying the blasting simulation model, the model size is reduced, shortening the calculation time. Based on the constraints of two-step pillar mining, the optimal target blast hole size for blasting effect is determined. This improves the model's calculation accuracy while maintaining computational efficiency, enhancing blasting effectiveness. It helps ensure the stability of the stope bottom structure and the first-step stope backfill, reduces ore loss and dilution in the second-step stope, improves the stability of ore deposit mining, effectively controls and improves the stope operating environment, and achieves the goals of economical, efficient, and safe mining. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the main process of a step-by-step mining method for underground mineral deposits based on numerical simulation, provided as an exemplary embodiment of this application.

[0024] Figure 2 This is a structural block diagram of a blast hole optimization device provided as an exemplary embodiment of this application. Detailed Implementation

[0025] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] Reference Figure 1 This application provides a step-by-step mining method for underground mineral deposits based on numerical simulation. The main steps of the method are described below.

[0028] S1: Divide the ore body into several panels at intervals along the strike of the ore body, and within these panels, divide the stope and pillar areas at intervals perpendicular to the strike of the ore body. S2: One-step stope recovery; S3: After the first-step stope mining is completed, pre-select the set of borehole sizes for simulation; S4: Obtain orebody property parameters that characterize the rock firmness coefficient and the degree of joint and fracture development, and determine the constraints for the two-step pillar mining. S5: Based on the set of borehole sizes, a preset simplified blasting simulation model is used, combined with the two-step pillar mining constraints, to output the target borehole size; S6: Based on the target borehole size, guide the two-step pillar recovery.

[0029] Specifically, for example, the panel is divided every 90 meters along the strike of the ore body, and the panel size is length (ore body width) × width (90m) × height (ore body thickness); within the panel, the stope (84m × 20m × stope thickness) and pillar stope (80m × 20m × pillar thickness) are divided every 20m along the vertical strike of the ore body.

[0030] The ore body recovery process includes the first step of mining the stope, followed by full tailings backfilling. The first step of mining is surrounded by original rock, with favorable mining conditions and relatively low ground pressure and stress.

[0031] After the first-stage stope mining is completed, a set of borehole sizes for simulation is pre-selected. Based on preliminary field test data and theoretical research, some borehole size parameters are pre-selected. In this embodiment, the borehole diameter can be 165mm, 120mm, or 110mm.

[0032] The secondary stopes are affected by the ore body itself, secondary joints and fissures, and the blasting and vibration damage from the primary stopes, resulting in significant wall spalling and over-extraction. In some secondary stopes, the thinnest over-extraction is only about 10 meters. A few stopes have well-developed geological structures, leading to large-scale interconnections between adjacent stopes, posing safety hazards to the secondary pillar stopes and even causing them to be unrecoverable and wasting resources. Furthermore, the rock and ore fragmentation in the drilling chambers and bottom structures of the secondary stopes is intensified, increasing the amount of repeated support required for mining operations. The unevenness of the backfill material on both sides is prominent, and tailings resin backfill material is easily mixed in, increasing the loss and dilution rate.

[0033] After the mining is completed in the first-stage mining area, a three-dimensional optical detector is used to continuously scan the goaf to form a three-dimensional goaf model for analysis, and to obtain ore body attribute parameters that characterize the rock firmness coefficient and the degree of joint and fracture development.

[0034] Obtain orebody property parameters characterizing rock firmness coefficient and joint and fracture development, and determine the constraints for two-step pillar mining, including: After the first-step stope mining is completed, the rock mass structure grade and structural surface condition grade of the preset target measuring points are obtained, and the geological strength value of the target measuring points is determined. The primary joint occurrence and secondary joint occurrence generated by the first-step stope mining of the preset target area are obtained, wherein the target measuring point is located in the target area; Based on the primary joint orientation and the secondary joint orientation, a pole map or joint distribution cloud map is generated to determine the dominant joint group in the target survey area; Based on the two-step pillar mining conditions, preset geological strength thresholds and dominant joint set thresholds are established. Based on the geological strength threshold and the dominant joint group threshold, a set of target survey areas and target survey points that meet the requirements are used as the constraint conditions for the two-step pillar mining.

[0035] By monitoring primary joints and fissures in the drilling chambers and bottom trenches of the second-stage mining area, as well as secondary joints and fissures generated by the mining operations of the first-stage mining area, a valid basis for evaluating the basic quality of the rock mass is provided. Before conducting detailed measurements at the selected measuring points, a reconnaissance survey is required to obtain preliminary information on the joints at that point, providing reference data for the next step of detailed investigation. After the reconnaissance survey is completed, the most representative section is selected for detailed measurement of the joint orientation. For example, a 30m long measuring line is laid at the measuring point location, with a height of 1.5m. Along the measuring line, a geological compass is used to measure the dip and dip angle of all joints intersecting the measuring line. The strike of the rock strata is the orientation of the line where the rock strata bedding plane intersects the horizontal plane. During measurement, the bottom edge of the long side of the compass is placed close to the rock strata bedding plane. When the bubble of the circular level is centered, the north direction or the degree indicated by the compass is the desired value. The dip direction of the rock strata refers to the orientation of the projection of the line of maximum downward dip of the rock strata onto the horizontal plane. During measurement, point the north end of the compass towards the downward dip direction of the rock strata, with the short edge of the south end against the bedding plane. When the bubble in the circular level is centered, read the degree indicated by the compass needle; this is the required angle. The dip angle of a rock strata refers to the maximum angle between the bedding plane and the imaginary horizontal plane, called the true dip angle. The true dip angle can be obtained by measuring along the true dip line of the bedding plane. If the dip angle measured along other dip lines is smaller than the true dip angle, it is called the apparent dip angle. During measurement, hold the compass on its side with its long edge against the bedding plane, and use the middle finger of your right hand to move the adjustable lever on the outside of the base while simultaneously moving the compass along the bedding plane. When the bubble in the tubular level is centered, the maximum degree indicated by the inclinometer needle is the true dip angle of the rock strata.

[0036] After measuring the joint orientation, the dominant joint groups are analyzed using pole plots or joint distribution cloud maps.

[0037] In this embodiment, taking the pole diagram as an example, based on the density of the pole distribution in the pole diagram, the set of points with a density higher than that of the surrounding area is taken as the dominant joint group.

[0038] The rock mass strength of the two-stage mining area is assessed using the Geological Strength Index (GSI). Target measuring points are pre-defined, and the rock mass structure grade (SR) and structural surface condition grade (SCR) are obtained at these points. SR is determined by the number of volumetric joints (Jv), while SCR is determined by three parameters: roughness score (Rr), weathering degree score (Rw), and infill condition score (Rf). Jv refers to the total number of intersecting joints per unit volume, measured in joints / m³. Rr is categorized into large-scale and medium-scale undulation and small-scale smoothness based on scale, determined by comparing roughness scores on a roughness score map. Rw can be determined using a pre-defined weathering degree rating table. Rf refers to the strength and thickness of the infill material, determined using a pre-defined infill material rating table. First, measure the four parameters Jv, Rr, Rw, and Rf. Then, solve the problem using the quantified GSI table. The measured Jv value needs to be converted into an SR value, and the Rr, Rw, and Rf values ​​need to be converted into SCR values. Then, the geological strength value of the target measuring point can be obtained by looking up the table.

[0039] Based on the two-step pillar mining conditions, preset threshold values ​​for geological strength and dominant joint groups are established.

[0040] The target measuring points with geological strength values ​​greater than or equal to the geological strength value threshold, and the target measuring area set with the density value of the dominant joint group greater than or equal to the dominant joint group threshold, that is, the geological strength value of the target measuring points in the target measuring area is greater than or equal to the geological strength value threshold, are used to obtain the two-step pillar mining constraint conditions.

[0041] Based on the set of borehole sizes, a preset simplified blasting simulation model is used, combined with the two-step pillar mining constraints, to output the target borehole size.

[0042] In one embodiment, the steps for constructing the simplified blasting simulation model include: Obtain the type of the main model; If the main body of the model is rock, the main body of the model is divided into Lagrange finite element meshes, and the Lagrange algorithm is used for modeling to obtain the first simulation model; If the main body of the model is an explosive, the main body of the model is divided into Eulerian finite element meshes, and the ALE algorithm is used for modeling to obtain the second simulation model; By coupling the first simulation model and the second simulation model, the simplified blasting simulation model is obtained.

[0043] Specifically, for rock blasting, a plastic dynamics material model can be used, which considers both the elastoplastic properties of the material and describes its strengthening effect and strain rate variation effect. Then, based on the field survey data, the type of the main body of the model is determined.

[0044] If the main body of the model is rock, the model is divided into Lagrange finite element meshes, and the Lagrange algorithm is used for modeling to obtain the first simulation model. The Lagrange (Method of Lagrange Multipliers) algorithm, also known as the Lagrange description method, is a core framework in solid mechanics numerical simulation for tracking the historical information of individual material particles, such as trajectory, velocity, stress, and damage.

[0045] In this embodiment, the rock can be represented by hexahedral solid elements. By defining linear elastic parameters such as Young's modulus and Poisson's ratio, and selecting a model such as the RHT model to describe the mechanical behavior of rock after yielding, including strain rate effects, pressure hardening, and tension-compression asymmetry, the maximum principal stress / strain failure is defined. The state equation is imported to describe the pressure-volume relationship, thus defining the constitutive and failure models. Next, loads such as the geostress field are applied to the model, and boundary conditions such as bottom surface fixation are constrained. Contact is defined, and automatic surface-to-surface contact is used to simulate large-scale contact and separation. An erosion algorithm is used to simulate the contact of newly formed crack surfaces, thus defining the interaction between blocks after fracture and creating the first simulation model.

[0046] After rock material is deformed, its free surface can be automatically captured by the boundary of the mesh. It can effectively simulate and reproduce the stress wave propagation, crack propagation, and rock throwing processes of rock explosion. Since there is no material flow in the mesh, it can effectively analyze various problems with moderate deformation, which helps to improve the accuracy of the model.

[0047] If the main body of the model is explosive, the model is divided into Eulerian finite element meshes, and the ALE algorithm is used for modeling to obtain the second simulation model. ALE (Arbitrary Lagrangian-Eulerian) is a hybrid numerical method that solves the problems of mesh distortion under large deformations in pure Lagrangian methods and inaccurate interface tracking in pure Eulerian methods. In explosive explosion modeling, the interaction between explosives and rocks during the explosion process involves complex application scenarios such as severe deformation, fluid-structure interaction, and material mixing. The ALE algorithm decouples the motion of the material from the mesh. In a single computational loop, the motion of the material, including its binding to the mesh, is calculated first in the Lagrange step; then, in the rezoning step, the distorted mesh is smoothed and rearranged to a more optimal position; finally, in the advection step, all physical quantities of the material points, such as mass, momentum, energy, and stress, are mapped from the old mesh to the new mesh. The mesh can be moved arbitrarily, combining the advantages of both the Lagrange and Euler algorithms.

[0048] In this embodiment, if the main body of the model is an explosive, a structured hexahedral Eulerian background mesh (ALE mesh) is used. By defining the explosive and air in the same ALE multimaterial mesh, an explosive geometric model containing the air domain is created. Next, using a high-explosive material containing equations of state, a material model and equations of state describing the pressure-volume-energy relationship of the explosive detonation products and an ideal gas equation of state characterizing the air material are defined to create a second simulation model.

[0049] The ALE algorithm combines the advantages of the Lagrange and Euler algorithms, solves the problem of fluid-fluid / fluid / solid structure interaction, is suitable for analyzing large deformation scenarios, and helps improve model accuracy.

[0050] Finally, the first and second simulation models are coupled to obtain the simplified blasting simulation model. Specifically, fluid-structure interaction (FSI) is defined to simulate the impact of explosives on rock. At each time step, by automatically detecting penetration between the ALE fluid mesh and the Lagrange solid mesh, a coupling algorithm is used, such as CTYPE=4 or 5, setting the coupling direction to bidirectional coupling, and the quality coefficient range to 0.05-0.28, to increase the accuracy and stability of the coupled model. By applying a "coupling force" at the penetrating nodes, the pressure in the ALE mesh of the second simulation model is transferred to the solid mesh of the first simulation model, causing it to move; simultaneously, the movement of the solid mesh of the first simulation model also affects the flow field in the ALE mesh of the second simulation model.

[0051] Next, the initial conditions such as the initial pressure and density of the air domain and the detonation point of the explosive are set; the detonation mode of the explosive, whether point-initiated or area-initiated, is set to automatically calculate the propagation of the detonation wave based on the detonation velocity; the transmission boundary of the ALE grid is set to simulate an infinite domain and prevent energy loss caused by non-physical reflection of pressure waves at the boundary, thus obtaining a simplified blasting simulation model.

[0052] By using explicit time integration to solve a simplified blasting simulation model, the expansion process of explosives and the propagation process of blasting shock waves are simulated. The relationship between blasting effect and borehole size, row spacing, and hole spacing is determined. An iterative approach is adopted in each calculation step, referencing the meshing results and convection calculations of the previous time step, eliminating the need for re-meshing and recalculation of convection. This greatly reduces the computational load of the model while achieving high-fidelity simulation of large deformation explosive-rock interaction scenarios, thus improving the accuracy of the model.

[0053] In one embodiment, the step of outputting the target borehole size based on the borehole size set, using a preset simplified blasting simulation model, and combining the two-step pillar mining constraints, includes: Initialize the simplified blasting simulation model; The dimensions of each borehole in the borehole size set are sequentially input into the simplified blasting simulation model, different row spacing and hole spacing are matched, and the holes are laid out and blasted in the manner of equal row spacing and hole spacing to obtain simulation results. Among them, the hole layout method selects two rows of blasting holes, and two boreholes are preset in each row for detonation. Based on the simulation results, the optimal row spacing and hole spacing for each borehole size are determined; Based on the constraints of the two-step pillar mining, the target borehole size is determined and output.

[0054] By initializing a simplified blasting simulation model, the dimensions of each borehole located in the borehole size set are sequentially input into the simplified blasting simulation model. Different row spacing, hole spacing, hole layout methods, and blasting methods are matched to intuitively display the simulation results of the rock damage area, crack propagation, and fracture zone range. The relationship between blasting effect and borehole size, row spacing, and hole spacing is determined. Finally, combined with the two-step pillar mining constraints, the target borehole size set at the target measuring point in the target measuring area is decided and output.

[0055] Because the boreholes have a certain degree of symmetry, to reduce the model size and shorten the computation time, two rows of boreholes can be used to simulate the blasting effect of multiple rows of boreholes. Symmetrical boundary conditions are applied to the model on the symmetry plane. For each row, two boreholes are selected for analysis to further reduce the model size and save computation time.

[0056] In one embodiment, the blasting method involves detonating two pre-set blast holes in each row sequentially at millisecond intervals. For example, two blast holes in a row are detonated sequentially at 4ms-6ms intervals.

[0057] Simulating multi-row, multi-hole blasting problems using two-hole differential blasting reduces the size of the computational model while improving blasting effectiveness. For example, when the stress wave from hole A has not fully attenuated, the stress wave from hole B arrives, creating stress superposition in the overlapping area and enhancing rock fragmentation. The fissures and cavities formed after the blast of hole A provide hole B with an additional, closer free surface, making the blasting conditions of hole B more favorable and reducing the proportion of large blocks.

[0058] In one embodiment, the step of determining the optimal row spacing and hole spacing for each borehole size based on the simulation results includes, Detect the simulation results; When the simulation result shows that no triangular spine appears in either of the two preset boreholes in each row, the currently matched row spacing and borehole spacing are increased by a preset threshold to be the optimal row spacing and borehole spacing for the current borehole size.

[0059] By observing the hole shape after the explosion of the ore and rock model, when obvious triangular spines appear in the middle or corner of the blast holes, the large pieces of ore that slide down the suspended triangular spines will have a great impact on the ore production. At this time, it is judged that the hole mesh parameters are too large. The optimization method of gradually reducing the row spacing and hole spacing can be adopted until no triangular spines appear in the two preset blast holes in each row.

[0060] In this embodiment, the row spacing and hole spacing of the same borehole diameter are first simulated with equal and smaller values. Based on the simulation results, the row spacing and hole spacing are gradually increased to optimize the process until no triangular spines appear in the two preset boreholes in each row.

[0061] The currently matched row spacing and hole spacing are increased by a preset threshold to obtain the optimal row spacing and hole spacing for the current borehole size. In this embodiment, the current row spacing and hole spacing are increased by 0.1m to obtain the optimal mesh parameters for the current borehole diameter, thus achieving the best mesh parameters while ensuring optimization efficiency.

[0062] Finally, based on the target borehole size, the two-step pillar recovery is guided, followed by full tailings backfilling.

[0063] In summary, a step-by-step mining method for underground deposits based on numerical simulation divides the ore body into several panels at intervals along the strike, and within these panels, further divides them into stopes and pillars at intervals perpendicular to the strike. Step-by-step mining of the underground deposit is achieved through these mining units, resulting in efficient and stable mining. After the first-step stope mining is completed, a set of borehole sizes for simulation is pre-selected to pre-determine blasting parameters suitable for the second-step pillar mining, improving the efficiency of subsequent blasting parameter optimization. Ore body property parameters characterizing the rock firmness coefficient and the degree of joint and fracture development are obtained to determine the constraints for the second-step pillar mining. This allows for blasting parameter optimization while effectively controlling blasting vibration and damage range and maintaining surrounding rock stability, which is beneficial for ensuring good blasting results. Based on the blasting... The borehole size set, using a pre-defined simplified blasting simulation model and combined with the constraints of two-step pillar mining, outputs the target borehole size to guide the two-step pillar mining. By simplifying the blasting simulation model, the model size is reduced, the calculation time is shortened, and the target borehole size with the best blasting effect is solved based on the constraints of two-step pillar mining. Thus, while ensuring the model's calculation efficiency, the calculation accuracy is improved, the blasting effect is enhanced, which helps to ensure the stability of the bottom structure of the stope and the backfill of the first-step stope, reduces the loss and dilution of ore in the second-step stope, improves the stability of the underground deposit during the second-step mining, ensures the smooth progress of underground deposit mining, effectively controls and improves the stope working environment, and achieves the goal of economical, efficient, and safe mining.

[0064] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0065] Reference Figure 2 This application also provides a blasting hole optimization device, which is applied to any of the numerical simulation-based step-by-step mining methods for underground deposits described in the above embodiments. The blasting hole optimization device includes... The borehole pre-selection module is used to pre-select a set of borehole sizes for simulation after the completion of the first-step stope mining. The constraint module is used to obtain orebody property parameters that characterize the rock firmness coefficient and the degree of joint and fracture development, and to determine the constraint conditions for the two-step pillar mining. The optimization module is used to output the target borehole size based on the borehole size set, using a preset simplified blasting simulation model, combined with the two-step pillar mining constraints.

[0066] For specific limitations regarding a blasting hole optimization device, please refer to the limitations of a step-by-step mining method for underground deposits based on numerical simulation mentioned above, which will not be repeated here.

[0067] The various modules in the aforementioned blasting hole optimization device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the operations corresponding to each module.

[0068] In one embodiment, a computer device is provided, which may be a server. The computer device includes a processor, memory, a network interface, and a database connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface is used to communicate with external terminals via a network connection. When the computer program is executed by the processor, it implements any of the above-described numerical simulation-based step-by-step mining methods for underground deposits.

[0069] In one embodiment, a computer-readable storage medium is provided, 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 any of the above-described numerical simulation-based step-by-step mining methods for underground deposits.

[0070] In one embodiment, a computer program product is provided, comprising a computer program that, when executed by a processor, implements any of the above-described numerical simulation-based step-by-step mining methods for underground deposits.

[0071] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. Any references to memory, storage, database, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0072] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the system can be divided into different functional units or modules to complete all or part of the functions described above.

Claims

1. A method for staged mining of underground mineral deposits based on numerical simulation, characterized in that, Includes the following steps, The ore body is divided into several panels at intervals along its strike, and within these panels, stopes and pillars are divided at intervals perpendicular to the strike of the ore body. One-step stope recovery; After the first-stage stope mining is completed, a set of borehole sizes is pre-selected for simulation; Obtain orebody property parameters that characterize the rock firmness coefficient and the degree of joint and fracture development, and determine the constraints for two-step pillar mining. Based on the set of borehole sizes, a preset simplified blasting simulation model is used, combined with the two-step pillar mining constraints, to output the target borehole size. Based on the target borehole size, the two-step pillar recovery is guided.

2. The method for staged mining of underground deposits based on numerical simulation according to claim 1, characterized in that, The steps of obtaining orebody property parameters characterizing the rock firmness coefficient and the degree of joint and fracture development, and determining the constraints for two-step pillar mining, include: After the first-step stope mining is completed, the rock mass structure grade and structural surface condition grade of the preset target measuring points are obtained, and the geological strength value of the target measuring points is determined. The primary joint occurrence and secondary joint occurrence generated by the first-step stope mining of the preset target area are obtained, wherein the target measuring point is located in the target area; Based on the primary joint orientation and the secondary joint orientation, a pole map or joint distribution cloud map is generated to determine the dominant joint group in the target survey area; Based on the two-step pillar mining conditions, preset geological strength thresholds and dominant joint set thresholds are established. Based on the geological strength threshold and the dominant joint group threshold, a set of target survey areas and target survey points that meet the requirements are used as the constraint conditions for the two-step pillar mining.

3. The method for staged mining of underground deposits based on numerical simulation according to claim 1, characterized in that, The steps for constructing the simplified blasting simulation model include: Obtain the type of the main model; If the main body of the model is rock, the main body of the model is divided into Lagrange finite element meshes, and the Lagrange algorithm is used for modeling to obtain the first simulation model; If the main body of the model is an explosive, the main body of the model is divided into Eulerian finite element meshes, and the ALE algorithm is used for modeling to obtain the second simulation model; By coupling the first simulation model and the second simulation model, the simplified blasting simulation model is obtained.

4. The method for staged mining of underground deposits based on numerical simulation according to claim 3, characterized in that, The step of outputting the target borehole size based on the borehole size set, using a preset simplified blasting simulation model, and combining the two-step pillar mining constraints, includes: Initialize the simplified blasting simulation model; The dimensions of each borehole in the borehole size set are sequentially input into the simplified blasting simulation model, different row spacing and hole spacing are matched, and the holes are laid out and blasted in the manner of equal row spacing and hole spacing to obtain simulation results. Among them, the hole layout method selects two rows of blasting holes, and two boreholes are preset in each row for detonation. Based on the simulation results, the optimal row spacing and hole spacing for each borehole size are determined; Based on the constraints of the two-step pillar mining, the target borehole size is determined and output.

5. The method for staged mining of underground deposits based on numerical simulation according to claim 4, characterized in that, The blasting method involves two pre-set blast holes in each row being detonated sequentially at millisecond intervals.

6. The method for staged mining of underground deposits based on numerical simulation according to claim 4, characterized in that, The step of determining the optimal row spacing and hole spacing for each borehole size based on the simulation results includes, Detect the simulation results; When the simulation result shows that no triangular spine appears in either of the two preset boreholes in each row, the currently matched row spacing and borehole spacing are increased by a preset threshold to be the optimal row spacing and borehole spacing for the current borehole size.

7. A device for optimizing blasting holes, characterized in that, Applied to the method of any one of claims 1 to 6, comprising, The borehole pre-selection module is used to pre-select a set of borehole sizes for simulation after the completion of the first-step stope mining. The constraint module is used to obtain orebody property parameters that characterize the rock firmness coefficient and the degree of joint and fracture development, and to determine the constraint conditions for the two-step pillar mining. The optimization module is used to output the target borehole size based on the borehole size set, using a preset simplified blasting simulation model, combined with the two-step pillar mining constraints.

8. A computer device, characterized in that, The method includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the method according to any one of claims 1 to 6.

10. A computer program product, characterized in that, It includes a computer program that, when executed by a processor, implements the steps of the method according to any one of claims 1 to 6.

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