Mining ground fracture erosion prediction method, device and equipment under freeze-thaw condition

Abstract

The invention provides a mining ground fracture erosion prediction method, device and equipment under a freeze-thaw condition, and belongs to the field of geological research, and the method comprises the steps: obtaining the related data of a target mining ground fracture; calculating a frost heaving stress field and a mining-induced tensile stress field based on the related data, and performing superposition to obtain a total tensile stress field; when the total tensile stress field is greater than the tensile strength of the soil, calculating the coupling damage degree; based on the coupling damage degree, the effective cohesion and the effective internal friction angle of the soil are determined, and then the critical starting shear stress of the crack and the average flow velocity of the scouring critical state are determined; based on the critical starting shear stress and the average flow velocity, total energy consumed for erosion and collapse of the soil body in unit area is determined, and actual water flow power is calculated; and calculating the ratio of the total energy to the actual water flow power to obtain a physical index of the anti-erosion comprehensive capability of the soil so as to judge the erosion risk state of the soil crack. Therefore, space-time prediction and accurate early warning of the erosion risk can be realized.

Description

Technical Field

[0001] This invention belongs to the field of geological research, specifically relating to a method, apparatus and equipment for predicting mining-induced ground fissure erosion under freeze-thaw conditions. Background Technology

[0002] Soil erosion resistance refers to the ease with which soil is eroded under external forces such as rainfall splash, runoff scouring, and interflow. While reflecting soil's ability to resist erosion, it is not an observable variable and cannot be directly observed; it can only be inferred through models or observable variables. Its strength is primarily determined by the affinity between soil and water and the cohesive force between soil particles, but it is influenced by various factors such as vegetation cover and human activities. Therefore, the quantitative evaluation of soil erosion resistance and the accurate acquisition of its parameters are fundamental to a deeper understanding of soil erosion processes and mechanisms, and are also prerequisites for improving the prediction accuracy and simulation capabilities of soil erosion process models and their wider application.

[0003] Currently, the calculation and evaluation indicators for soil erosion resistance have evolved from single indicators to multiple indicators. Because soil erosion resistance is related to many factors such as soil texture, soil aggregate stability, and organic matter content, its quantitative characterization is often significantly affected by the natural environment and human activities, resulting in significant regional differences. Therefore, there is still no universally applicable evaluation indicator.

[0004] Freeze-thaw action, as a typical external force in cold regions, inevitably has a profound impact on soil erosion, a fact widely recognized by academic and engineering construction circles both domestically and internationally. Human mining activities also have a far-reaching impact on soil erosion. However, no relevant methods have been found to consider both as important factors and conditions for evaluating soil erosion resistance. In other words, there is a lack of evaluation methods for special areas with "natural external forces + intense human activities," resulting in insufficient targeting of soil erosion prevention and control measures for these special areas and limited treatment effects. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method, apparatus, and equipment for predicting mining-induced ground fissure erosion under freeze-thaw conditions.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A method for predicting mining-induced ground fissure erosion under freeze-thaw conditions, the method comprising: Acquire soil mechanical parameters, temperature, moisture content and geometric data of the target mining-induced ground fissures, and obtain dynamic strain field data of the surface through mining activity data; Based on the soil mechanical parameters, temperature, and moisture content data, the frost heave stress field generated by freeze-thaw action is calculated; based on the dynamic strain field data and crack geometry data, the mining-induced tensile stress field generated by mining activities is calculated; the frost heave stress field and the mining-induced tensile stress field are superimposed to obtain the total tensile stress field; when the total tensile stress field is greater than the tensile strength of the soil, the coupling damage degree characterizing the degree of crack propagation is calculated; Based on the aforementioned coupling damage degree, the cohesion and internal friction angle of the undisturbed soil are reduced to determine the effective cohesion and effective internal friction angle of the soil under the current damage state. Based on the effective cohesion and effective internal friction angle, the critical starting shear stress of the soil matrix between the cracks to resist water stripping is calculated; based on the residual strength of the crack wall material and the crack geometry data, the average flow velocity of water reaching the critical scouring state inside the crack is calculated. The total energy required for soil per unit area to be eroded and disintegrated is determined based on the critical starting shear stress and the average flow velocity; the actual flow power is calculated based on the pre-acquired water flow shear stress and surface flow velocity data; by calculating the ratio of total energy to actual flow power, the physical index of soil erosion resistance is obtained, and the erosion risk status of soil cracks is determined.

[0007] Optionally, when the total tensile stress field exceeds the tensile strength of the soil, the calculation of the coupled damage degree characterizing the degree of crack propagation includes: The coupled damage degree is determined based on the initial crack density, average length, average width, and crack widening effect caused by the coupling of frost heave and mining stress, using the following formula: ; in, For coupling damage degree, The initial crack density, The average crack length, The initial average crack width. This is the frost heave expansion coefficient. For the total tensile stress, For soil tensile strength, This refers to the soil's elastic modulus.

[0008] Optionally, the formula for calculating the effective cohesion is: ; The formula for calculating the effective internal friction angle is: ; in, For the cohesion of the original soil, The internal friction angle of the undisturbed soil. and It is an experience index.

[0009] Optionally, the formula for calculating the critical starting shear stress is: ; in, This is the critical starting shear stress. For effective cohesion, For the effective internal friction angle, This refers to the effective normal stress acting on the matrix surface.

[0010] Optionally, calculating the average flow velocity within the fracture to reach the critical scour state based on the residual strength of the fracture wall material and fracture geometry data includes: The correlation between the residual strength of the fracture wall material and the Manning roughness coefficient, which is negatively correlated with it, is established. Then, based on hydraulic principles, the average flow velocity at the critical scour state is calculated using the Manning roughness coefficient. Finally, the correlation between the residual strength of the fracture wall material, fracture geometry data, and average flow velocity is obtained. ; in, The average flow velocity, The residual strength of the crack wall material. The slope of the crack.

[0011] Optionally, the formula for calculating the comprehensive physical index of soil erosion resistance is as follows: ; in, This represents the actual water flow power. This represents the total energy required for a unit area of ​​soil to be eroded and disintegrated. For water flow shear stress, This represents the actual surface flow rate.

[0012] Optionally, after determining the erosion risk status of soil cracks, the method further includes: The physical index of soil erosion resistance is spatially visualized on a geographic information system platform, and prevention and control measures are recommended based on the assessment results.

[0013] A device for predicting erosion of mining-induced ground fissures under freeze-thaw conditions, the device comprising: The acquisition module is used to acquire soil mechanical parameters, temperature, moisture content data and geometric data of the target mining-induced ground fissures, and to acquire dynamic strain field data of the surface through mining activity data; The calculation module is used to calculate the frost heave stress field generated by freeze-thaw action based on the soil mechanical parameters, temperature and moisture content data; to calculate the mining-induced tensile stress field generated by mining activities based on the dynamic strain field data and crack geometry data; to superimpose the frost heave stress field and the mining-induced tensile stress field to obtain the total tensile stress field; and to calculate the coupling damage degree characterizing the degree of crack propagation when the total tensile stress field is greater than the tensile strength of the soil. The determination module is used to reduce the cohesion and internal friction angle of the undisturbed soil based on the coupled damage degree, and determine the effective cohesion and effective internal friction angle of the soil under the current damage state; based on the effective cohesion and effective internal friction angle, calculate the critical starting shear stress of the soil matrix between the cracks to resist water flow stripping; and based on the residual strength of the crack wall material and the crack geometry data, calculate the average flow velocity of water inside the crack to reach the critical scour state. The judgment module is used to determine the total energy required for soil per unit area to be eroded and disintegrated based on the critical starting shear stress and the average flow velocity; to calculate the actual flow power based on the pre-acquired water flow shear stress and surface flow velocity data; and to obtain the physical index of soil erosion resistance by calculating the ratio of total energy to actual flow power, thereby determining the erosion risk status of soil cracks.

[0014] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for predicting ground fissure erosion under freeze-thaw conditions.

[0015] 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 program to implement the above-described method for predicting mining-induced ground fissure erosion under freeze-thaw conditions.

[0016] The method for predicting ground fissure erosion under freeze-thaw conditions provided by this invention has the following beneficial effects: By obtaining the basic soil parameters and fracture geometric data, for the first time, the frost heave stress field and the mining-induced tensile stress field are coupled and superimposed at the mechanical level, accurately revealing the synergistic failure essence of the two on the ground fissure system, and overcoming the limitation of the traditional method of treating each factor in isolation. By calculating the coupling damage degree and dynamically reducing the soil strength parameters, the quantitative tracking of the evolution process of soil structure damage is realized, making the evaluation index closely related to the actual erosion physical process. Further, by calculating the critical starting shear stress of the matrix area and the critical scouring velocity of the fracture system respectively, a mechanical threshold system for anti-erosion based on the "dual medium" model is constructed, so as to comprehensively characterize the unique erosion mechanism in the fracture development area. Finally, by comparing the energy required for soil disintegration with the actual water flow power, the obtained physical index realizes the dynamic and intuitive judgment of the stable state of the system. The application of this method can realize the spatio-temporal prediction and accurate early warning of erosion risk, directly guide the implementation of differential targeted prevention and control measures for high stress concentration areas and strong damage areas, effectively promote the leap of the governance mode from passive remediation to active prevention and control, and finally significantly enhance the scientific nature and governance effectiveness of soil and water conservation projects in special areas such as cold mining areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention and their design schemes, the accompanying drawings required for this embodiment will be briefly introduced below. The accompanying drawings in the following description are only partial embodiments of the present invention. For those of ordinary skill in the art, other accompanying drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 It is a schematic flowchart of a method for predicting mining-induced ground fissure erosion under freeze-thaw conditions provided by the present invention according to an exemplary embodiment.

[0019] Figure 2 It is a schematic diagram of the overall structure of a detection tool provided by the present invention according to an exemplary embodiment.

[0020] Figure 3 It is a schematic diagram of a "square frame-shaped" rectangular plate structure provided by the present invention according to an exemplary embodiment.

[0021] Figure 4 It is a schematic diagram of a "rectangular block" structure provided by the present invention according to an exemplary embodiment.

[0022] Figure 5 It is a block diagram of a device for predicting mining-induced ground fissure erosion under freeze-thaw conditions provided by the present invention according to an exemplary embodiment.

[0023] Reference numerals in the drawings: 1 - "square frame-shaped" rectangular plate; 2 - scale of the rectangular plate; 3 - groove; 4 - rectangular block; 5 - 1 / 4 circular member; 6 - cylindrical member; 7 - angle scale. Detailed implementation manners

[0024] To enable those skilled in the art to better understand the technical solution of the present invention and be able to implement it, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention and should not be used to limit the protection scope of the present invention.

[0025] The present invention proposes a calculation method for the comprehensive soil erosion resistance in the goaf ground fissure development area under freeze-thaw conditions. The method consists of two parts. The first part is a mathematical model, and the second part is a detection tool for the parameters used in the model. The mathematical model innovatively establishes a coupled stress field and damage evolution equation, quantifying the synergistic amplification effect of frost heaving stress and mining tensile stress at the mechanical level. Using physical parameters based on soil mechanics and fluid mechanics, the erosion mechanism dominated by cracks is accurately characterized through the "dual medium" model. It has the ability of dynamic early warning, and realizes the spatio-temporal prediction of the erosion critical state through the physical index of the comprehensive soil erosion resistance. For the first time, a dedicated evaluation tool is provided for cold mining areas, and the output results can directly guide targeted prevention and control. For example, anti-freezing swelling filling is preferentially implemented in high stress concentration areas, significantly improving the governance accuracy and engineering efficiency, and achieving the leap from passive governance to active prevention and control.

[0026] The following will describe in detail the technical solutions provided by each embodiment of the present invention with reference to the accompanying drawings.

[0027] First, the present invention provides a method for predicting goaf ground fissure erosion under freeze-thaw conditions, specifically as Figure 1 shown, including the following steps: S101. Obtain the soil mechanics parameters, temperature, moisture content data and geometric data of the target goaf ground fissure, and obtain the dynamic strain field data of the ground surface through mining activity data.

[0028] The crack width and the slope of the crack side wall in the mathematical model are two main parameters. For this reason, this step proposes a portable width and slope detection tool.

[0029] As Figure 2 shown, the tool consists of two functional parts. One part is the width measurement function, and the other part is the side wall slope measurement function. Correspondingly, the tool is mainly divided into two parts. One part is the width measurement part, and the other part is the slope measurement part. These two parts are mainly composed of a "rectangular frame" rectangular plate and a "rectangular block".

[0030] The plane of the "rectangular frame" rectangular plate is a hollow structure, and there is a groove on the long side of the hollow structure. There is a nearly 1 / 4 circular member at the bottom of the "rectangular frame" rectangular plate. As Figure 3 shown, the side is an arc with a width, and there are angular scales on the arc. There are scales on the plane of the "rectangular frame" rectangular plate to measure the crack width.

[0031] The current state of the "rectangular block" plane is in the shape of a semicircle connected to a rectangle, as Figure 4 shown. There are two cylindrical components protruding from the rectangular block at the upper part. The components penetrate into the grooves of the "double-square" rectangular plate and are connected to it as a whole.

[0032] When measuring the width, press the "double-square" rectangular plate tightly against the slope where the crack is located, and then press the two rectangular blocks tightly against the side walls of the crack. Among them, the upper part of the left rectangular block should be aligned with the 0 scale. The distance between the upper parts of the two rectangular blocks is the width of the measured crack.

[0033] When measuring the slope, similar to the width measurement, press the "double-square" rectangular plate tightly against the slope where the crack is located, and then press the two rectangular blocks tightly against the side walls of the crack. However, at the beginning, the 0° scale of the 1 / 4 circular component should be in a straight line with the inner long side of the rectangular block, and then slowly press the inner side of the rectangular block against the slope of the side wall of the crack. At this time, the rectangular block rotates, and during the rotation, its bottom end no longer coincides with 0°, but points to other scales, and this scale is the slope of the side wall of the crack.

[0034] S102. Based on the soil mechanics parameters, temperature, and moisture content data, calculate the frost heave stress field generated by freeze-thaw action; based on the dynamic strain field data and the geometric data of the crack, calculate the mining-induced tensile stress field; superimpose the frost heave stress field and the mining-induced tensile stress field to obtain the total tensile stress field; when the total tensile stress field is greater than the tensile strength of the soil, calculate the coupled damage degree characterizing the crack expansion degree.

[0035] In this step, first calculate the frost heave stress field. The frost heave stress generated by the phase change of single pore water ice can be expressed as:

[0036] [[ID=2s1]] ; In the formula: is the constraint coefficient (related to the soil boundary conditions); is the elastic modulus of the soil; is the pore water phase change efficiency coefficient (about 0.09); is the volume content of unfrozen water before freezing; and are the densities of water and ice.

[0037] Secondly, calculate the tensile stress field caused by mining. The surface tensile strain caused by coal mining generates stress concentration at the tip of the ground fissure, and the tensile stress near it is:

[0038] ; Among them, the stress intensity factor Related to crack geometry data; , This represents the crack depth. Let be the radius of curvature at the crack tip.

[0039] Frost heave stress and mining tensile stress superimpose in the crack region, forming total tensile stress. for: ; when > When the soil tensile strength is measured, primary mining-induced cracks widen and extend under freeze-thaw cycles, generating new secondary frost heave cracks. The resulting coupled damage degree is defined as follows. for:

[0040] ; In the formula: and The crack area and the total area; For coupling damage degree, The initial crack density, The average crack length, The initial average crack width. This is the frost heave expansion coefficient. For the total tensile stress, For soil tensile strength, This refers to the soil's elastic modulus.

[0041] The calculation of the coupled damage degree takes into account the initial crack density, average length, average width, and crack widening effect caused by the coupling of frost heave and mining stress.

[0042] S103. Based on this coupled damage degree, the cohesion and internal friction angle of the undisturbed soil are reduced to determine the effective cohesion and effective internal friction angle of the soil under the current damage state.

[0043] The coupling effect of freeze-thaw cycles and mining causes changes in the effective mechanical parameters of the soil, and these changes can be represented by nonlinear exponential functions. These exponents are generally empirical, obtained through long-term measurement and analysis.

[0044] The formula for calculating the effective cohesion is as follows: ; The formula for calculating the effective internal friction angle is: ; in, For the cohesion of the original soil, The internal friction angle of the undisturbed soil. and It is an experience index.

[0045] S104. Based on the effective cohesion and effective internal friction angle, calculate the critical starting shear stress of the soil matrix between the cracks to resist water flow stripping; based on the residual strength of the crack wall material and the crack geometry data, calculate the average flow velocity of water reaching the critical scouring state inside the crack.

[0046] The formula for calculating the critical initiation shear stress of soil blocks between cracks to resist water stripping is as follows: ; in, This is the critical starting shear stress. For effective cohesion, For the effective internal friction angle, This refers to the effective normal stress acting on the matrix surface.

[0047] In this step, the calculation of the average flow velocity of water reaching the critical scour state inside the crack first establishes the correlation between the residual strength of the crack wall material and the Manning roughness coefficient, which is negatively correlated with it. Then, based on hydraulic principles, the average flow velocity at the critical scour state is calculated using the Manning roughness coefficient. Finally, the correlation between the residual strength of the crack wall material, the crack geometry data, and the average flow velocity is obtained.

[0048] For the crack itself, its erosion resistance depends on the residual strength of the crack wall material. (usually much smaller) The average flow velocity at which water reaches the critical scouring state in the crack. It can be derived by combining the modified Manning formula with the critical shear stress:

[0049] ; in, For hydraulic radius, For the slope of the crack; crack Manning roughness Related to residual strength: ,and satisfy: ; Therefore, it can be deduced that: ; in, The average flow velocity, The residual strength of the crack wall material. The slope of the crack.

[0050] S105. Based on the critical starting shear stress and the average flow velocity, determine the total energy required for soil per unit area to be eroded and disintegrated; based on the pre-acquired water flow shear stress and surface flow velocity data, calculate the actual water flow power; by calculating the ratio of total energy to actual water flow power, obtain the physical index of soil erosion resistance, and then determine the erosion risk status of soil cracks.

[0051] In this step, we first define a physical index based on the principle of energy conservation: the energy required for a unit area of ​​soil to be eroded and disintegrated. It can be represented as: ; In the formula The energy required for matrix disintegration can be expressed by the following formula: ; The energy required to scour the cracks can be expressed by the following formula: ; The physical index of soil erosion resistance is the ratio of disintegration energy per unit area to actual water flow power, and its calculation formula is as follows: ; in, This represents the actual water flow power. This represents the total energy required for a unit area of ​​soil to be eroded and disintegrated. For water flow shear stress, This represents the actual surface flow rate.

[0052] when When the value is greater than 1, the current crack system is stable, and the water flow power is insufficient to erode the soil.

[0053] when When the value is approximately 1, the current state is critical and no erosion occurs.

[0054] when When the value is less than 1, severe erosion occurs in the current crack.

[0055] In addition, after determining the erosion risk status of soil cracks, the physical index of the soil's comprehensive erosion resistance can be spatially visualized on a geographic information system platform, and targeted prevention and control measures can be recommended based on the assessment results.

[0056] Based on the above method, the present invention also provides an embodiment comprising five stages.

[0057] Phase 1: Basic data collection.

[0058] Geological survey data: Basic soil mechanical parameters were obtained through field tests (direct shear and triaxial).

[0059] Meteorological monitoring data: Establish automatic weather stations to continuously monitor temperature, moisture content, rainfall, etc.

[0060] Mining activity data: Combine mining plans with subsidence projections to obtain dynamic strain field data.

[0061] Phase Two: Physical Model Calculation.

[0062] The core of coupled calculation is to superimpose the freeze-thaw and mining effects at the mechanical level.

[0063] Damage evolution tracking: Real-time calculation of the expansion and connectivity of the crack network.

[0064] Strength decay quantification: predicting the degradation path of material properties based on damage degree.

[0065] This stage is the core stage of the present invention.

[0066] Phase 3: Assessment of erosion resistance.

[0067] Dynamic index calculation: The physical index of soil's comprehensive resistance to erosion changes dynamically with environmental conditions.

[0068] Risk level classification: Establish clear numerical boundaries to correspond to different risk states.

[0069] Spatiotemporal prediction capability: It can predict the risk evolution trend within future freeze-thaw cycles.

[0070] Phase 4: Output and Application of Results

[0071] Spatial visualization: Generate a single map of erosion risk on the GIS platform.

[0072] More precise early warnings: simultaneously warning high-risk "areas" and key "time periods".

[0073] Targeted measures: Recommend targeted measures based on the failure mechanisms of different regions.

[0074] Phase 5: Output and Application of Results

[0075] Spatial visualization: Generate a single map of erosion risk on the GIS platform.

[0076] More precise early warnings: simultaneously warning high-risk "areas" and key "time periods".

[0077] Targeted measures: Recommend targeted measures based on the failure mechanisms of different regions.

[0078] Using the aforementioned method, by acquiring basic soil parameters and crack geometry data, this study, for the first time, couples and superimposes the frost heave stress field and the mining tensile stress field at the mechanical level. This accurately reveals the synergistic destructive nature of these two forces on the ground fissure system, overcoming the limitations of traditional methods that isolate various factors. By calculating the coupled damage degree and dynamically reducing soil strength parameters, the evolution of soil structural damage is quantitatively tracked, closely linking evaluation indicators with actual erosion physics. Furthermore, by calculating the critical initiation shear stress in the matrix region and the critical scour velocity in the fissure system, an erosion resistance mechanical threshold system based on a "dual-medium" model is constructed, enabling a comprehensive characterization of the unique erosion mechanism in the fissure development zone. Finally, by comparing the energy required for soil disintegration with the actual water flow power, the resulting physical indices provide a dynamic and intuitive assessment of the system's stable state. The application of this method enables spatiotemporal prediction and accurate early warning of erosion risks, directly guiding the implementation of differentiated targeted prevention and control measures for high stress concentration areas and areas with severe damage. This effectively promotes the transformation of the governance model from passive remediation to proactive prevention and control, and ultimately significantly enhances the scientific nature and governance effectiveness of soil and water conservation projects in special areas such as cold mining areas.

[0079] Secondly, the present invention also provides a device for predicting the erosion of mining-induced ground fissures under freeze-thaw conditions, such as... Figure 5 As shown, it includes: The acquisition module 201 is used to acquire soil mechanical parameters, temperature, moisture content data and geometric data of the target mining-induced ground fissures, and to acquire dynamic strain field data of the surface through mining activity data.

[0080] The calculation module 202 is used to calculate the frost heave stress field generated by freeze-thaw action based on the soil mechanical parameters, temperature and moisture content data; calculate the mining tensile stress field generated by mining activities based on the dynamic strain field data and crack geometry data; superimpose the frost heave stress field and the mining tensile stress field to obtain the total tensile stress field; and calculate the coupling damage degree characterizing the degree of crack propagation when the total tensile stress field is greater than the tensile strength of the soil.

[0081] The determination module 203 is used to reduce the cohesion and internal friction angle of the undisturbed soil based on the coupled damage degree, and determine the effective cohesion and effective internal friction angle of the soil under the current damage state; based on the effective cohesion and effective internal friction angle, calculate the critical starting shear stress of the soil matrix between the cracks to resist water flow stripping; based on the residual strength of the crack wall material and the crack geometry data, calculate the average flow velocity of water inside the crack to reach the critical scouring state.

[0082] The judgment module 204 is used to determine the total energy required for soil per unit area to be eroded and disintegrated based on the critical starting shear stress and the average flow velocity; to calculate the actual flow power based on the pre-acquired water flow shear stress and surface flow velocity data; and to obtain the physical index of soil erosion resistance by calculating the ratio of total energy to actual flow power, thereby determining the erosion risk status of soil cracks.

[0083] The present invention also provides a computer-readable storage medium storing a computer program that can be used to execute the above-described... Figure 1 The steps of the method for predicting mining-induced ground fissure erosion under freeze-thaw conditions are provided.

[0084] This invention also provides a computer device. At the hardware level, the computer device includes a processor, an internal bus, a network interface, memory, and non-volatile memory, and may also include other hardware required for various operations. The processor reads the corresponding computer program from the non-volatile memory into memory and then executes it to achieve the above-mentioned functions. Figure 1 The steps of the method for predicting mining-induced ground fissure erosion under freeze-thaw conditions are provided.

[0085] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0086] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0087] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0088] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0089] It should be noted that the specific embodiments described above enable those skilled in the art to more fully understand the present invention, but do not limit the present invention in any way. Therefore, although the present invention has been described in detail in this specification, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention; and all technical solutions and improvements that do not depart from the spirit and scope of the present invention are covered within the protection scope of the patent of the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for predicting mining-induced ground fissure erosion under freeze-thaw conditions, characterized in that, The method comprises: obtaining soil mechanical parameters, temperature, moisture content data and geometric data of target mining-induced ground fissure, and obtaining dynamic strain field data of the ground surface through mining activity data; based on the soil mechanical parameters, temperature and moisture content data, calculating the frost heaving stress field generated by freezing and thawing; based on the dynamic strain field data and the geometric data of the fissure, calculating the mining-induced tensile stress field generated by mining activities; superimposing the frost heaving stress field and the mining-induced tensile stress field to obtain the total tensile stress field; when the total tensile stress field is greater than the tensile strength of the soil, calculating the coupling damage degree representing the extent of crack propagation; based on the coupling damage degree, reducing the cohesion and internal friction angle of the undisturbed soil to determine the effective cohesion and effective internal friction angle of the soil under the current damage state; based on the effective cohesion and effective internal friction angle, calculating the critical starting shear stress of the soil matrix between the cracks to resist the flow stripping; based on the residual strength of the crack wall material and the geometric data of the crack, calculating the average flow velocity of the flow reaching the scour critical state inside the crack; based on the critical starting shear stress and the average flow velocity, determining the total energy consumed by the unit area of soil to be eroded and disintegrated; based on the pre-obtained flow shear stress and surface flow velocity data, calculating the actual flow power; by calculating the ratio of the total energy and the actual flow power, obtaining the soil erosion resistance comprehensive ability physical index, and then determining the erosion risk state of the soil fissure.

2. The method of claim 1, wherein, When the total tensile stress field exceeds the tensile strength of the soil, the coupling damage degree representing the extent of crack propagation is calculated, which comprises: based on the density, average length, average width of the initial crack and the crack widening effect caused by the coupling of frost heaving and mining stress, the coupling damage degree is determined, and the formula is: ； wherein, is the coupling damage degree, is the initial crack density, is the average crack length, is the initial average crack width, is the frost heave expansion coefficient, is the total tensile stress, is the soil tensile strength, is the soil elastic modulus.

3. The method of claim 2, wherein, The formula for calculating the effective cohesion is: ； The formula for calculating the effective internal friction angle is: ； wherein, is the cohesion of the undisturbed soil, is the internal friction angle of the undisturbed soil, and is an empirical exponent.

4. The method of claim 3, wherein, The formula for calculating the critical starting shear stress is: ； wherein, is the critical onset shear stress, is the effective cohesion, is the effective internal friction angle, is the effective normal stress acting on the surface of the matrix.

5. The method of claim 1, wherein, Based on the residual strength of the crack wall material and the geometric data of the crack, the average flow velocity of the flow reaching the scour critical state inside the crack is calculated, which comprises: a correlation between the residual strength of the crack wall material and the Manning roughness coefficient negatively correlated therewith is constructed, and then based on the principles of hydraulics, the average flow velocity of the scour critical state is calculated through the Manning roughness coefficient, and finally the correlation between the residual strength of the crack wall material, the geometric data of the crack and the average flow velocity is obtained: ； wherein is the average flow velocity, is the residual strength of the fracture wall material, is the slope of the fracture.

6. The method of claim 1, wherein, The formula for calculating the soil erosion resistance comprehensive ability physical index is: ； wherein, P is the actual water flow power, E is the total energy consumed by the soil body per unit area to be eroded and disintegrated, τ is the water flow shear stress, V is the actual surface flow velocity.

7. The method of claim 1, wherein, After completing the erosion risk state determination of the soil fissure, the method further comprises: spatially visualizing the soil erosion resistance comprehensive ability physical index on a geographic information system platform, and generating prevention and control measures suggestions according to the evaluation results.

8. A device for predicting mining-induced ground fissure erosion under freeze-thaw conditions, characterized by, The device comprises: an acquisition module for obtaining soil mechanical parameters, temperature, moisture content data and geometric data of target mining-induced ground fissure, and obtaining dynamic strain field data of the ground surface through mining activity data; The computing module is configured to calculate a frost heaving stress field generated by freeze-thaw action based on the soil mechanical parameters, temperature and moisture content data, calculate a mining-induced tensile stress field generated by mining activities based on the dynamic strain field data and the geometric data of the cracks, superimpose the frost heaving stress field and the mining-induced tensile stress field to obtain a total tensile stress field, and calculate a coupling damage degree representing the degree of crack propagation when the total tensile stress field is greater than the tensile strength of the soil. The determining module is configured to reduce the cohesion and internal friction angle of the undisturbed soil based on the coupling damage degree, determine the effective cohesion and effective internal friction angle of the soil in the current damage state, calculate a critical starting shear stress of the soil matrix between cracks resisting water flow stripping based on the effective cohesion and effective internal friction angle, and calculate an average flow velocity of water flow reaching a scouring critical state inside the cracks based on the residual strength of the crack wall material and the geometric data of the cracks. The judging module is configured to determine the total energy consumed by the soil body per unit area for erosion and disintegration based on the critical starting shear stress and the average flow velocity, calculate an actual water flow power based on the pre-acquired water flow shear stress and surface flow velocity data, obtain a soil erosion resistance comprehensive ability physical index by calculating the ratio of the total energy and the actual water flow power, and determine the erosion risk state of the soil cracks.

9. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, and the computer program is executed by the processor to implement the method in any one of claims 1-7.

10. A computer device, comprising: The computer program is stored in the memory and executable on the processor, and the processor implements the method in any one of claims 1-7 when executing the program. The computer program is stored in the memory and executable on the processor, and the processor implements the method in any one of claims 1-7 when executing the program.

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