A quantitative calculation method for stability of freezing-thawing damage of a cold region dump

Abstract

The application discloses a kind of cold region dump freeze-thaw damage stability quantitative calculation method, it is related to mine safety detection technical field, by the influence of constantly moving thawing front in the spring thawing process of cold region dump, it is separately identified from traditional overall freeze-thaw reduction, and by the cutting relationship of dangerous zone Dzb of thawing front front edge and potential sliding surface data Slp forms overlap data Ovd, so that safety factor Fsf no longer only reflects the overall average stability state of dump, but can be corresponding to specific calculation period Tim And specific dangerous area;For example, after the temperature rises in spring, the surface layer of slope is first thawed while the deep part is still frozen, the position of thawing front Frt advancing process that can be identified is most likely to cause the position of reduced resistance to sliding, and the stability result Sta that is closer to the actual instability risk during spring thawing period is obtained by correcting the resistance to sliding Rsf, thereby reducing the problems of lagging judgment in dangerous period, deviation in dangerous area positioning and overestimation of safety factor Fsf.

Description

Technical Field

[0001] This invention relates to the field of mine safety testing technology, specifically a quantitative calculation method for freeze-thaw damage stability of spoil heaps in cold regions. Background Technology

[0002] In the long-term process of disposing of overburden and waste rock, open-pit mines in cold regions will form large-scale spoil heaps. These spoil heaps are affected by low-temperature freezing, spring thawing, snowmelt infiltration, and the loose accumulation structure of the spoil. Their stability assessment cannot be limited to conventional slope geometry and geotechnical parameter calculations. Instead, quantitative calculations are needed to consider the impact of freeze-thaw damage on the anti-sliding capacity and safety factor of spoil heaps in cold regions.

[0003] In existing stability analyses of spoil heaps in cold regions, the effects of freeze-thaw cycles are typically simplified to the number of freeze-thaw cycles, overall thawing depth, uniform strength reduction, or monitoring displacement thresholds. In actual spring thaw processes, the leading edge of the thawing front is a moving region that continuously advances into the spoil heap. This region often experiences phase change softening, meltwater accumulation, and structural disturbance simultaneously. If calculations are still performed based on fixed regional or overall parameters, it becomes difficult to determine whether the potential slip surface is being cut through by the leading edge of the thawing front at a given moment, and it is also difficult to quantitatively reflect the impact of this cutting relationship on the anti-slip force and safety factor. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a quantitative calculation method for freeze-thaw damage stability of spoil heaps in cold regions, thus solving the problems mentioned in the background section.

[0005] This invention is achieved through the following technical solution: a method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions, comprising the following steps: S1. Obtain the field model data Mod, temperature data Tmp, and anti-sliding data Rst of the cold region spoil heap. According to the acquisition time order of the temperature data Tmp, determine the time interval between two adjacent acquisition times in the temperature data Tmp as the calculation time period Tim. Perform coordinate unification and time unification processing on the field model data Mod, temperature data Tmp, and anti-sliding data Rst to form the basic dataset Bas. S2. Based on the field model data Mod and temperature data Tmp in the basic dataset Bas, calculate the spatial boundary between the thawed and unthawed areas in the cold region spoil dump at the end of each calculation period Tim, and determine the spatial boundary as the thawing front position Frt of the corresponding calculation period Tim. S3. Based on the thawing front position Frt corresponding to the termination of two adjacent calculation periods Tim, extract the spatial area formed by the thawing front position Frt advancing into the cold region spoil dump between two adjacent calculation periods Tim, and determine this spatial area as the thawing front leading danger zone Dzb. S4. Based on the field model data Mod in the basic dataset Bas, determine the potential slip surface data Slp, calculate the spatial overlap relationship between the potential slip surface data Slp and the danger zone Dzb at the leading edge of the thawing front, generate the overlap data Ovd, and use the overlap data Ovd as the quantitative basis for the influence of freeze-thaw damage on the anti-slip force, correct the anti-slip force corresponding to the potential slip surface data Slp, and generate the corrected anti-slip force Rsf. S5. Calculate the safety factor Fsf based on the modified anti-skid force Rsf and the anti-skid data Rst in the basic dataset Bas, and generate a stable result Sta based on the safety factor Fsf corresponding to each calculation period Tim. The stable result Sta includes the dangerous period corresponding to the minimum safety factor Fsf and the dangerous area corresponding to the minimum safety factor Fsf.

[0006] Preferably, step S1 includes: S11. Collect the spatial boundary, slope elevation, slope top line and slope toe line of the spoil heap from the existing surveying results or three-dimensional terrain model of the spoil heap in the cold region, and transfer the spatial boundary, slope elevation, slope top line and slope toe line of the spoil heap to the same computing environment. S12. Unify the coordinates of the spatial boundary, slope elevation, slope top line and slope toe line of the spoil heap, and divide it into multiple calculation units Cel according to the grid division method or the profile division method. S13. Combine the position, elevation range, and adjacency relationship of each calculation unit Cel with the spatial boundary of the spoil heap, slope elevation, slope top line, and slope toe line to obtain the field model data Mod.

[0007] Preferably, step S1 further includes: S14. Collect a temperature sequence with collection time and temperature value from the existing temperature records of the cold region spoil heap, and transmit the temperature sequence to the same computing environment; S15. Sort the temperature sequence according to the collection time from earliest to latest to obtain the temperature data Tmp; S16. The time interval between two adjacent acquisition times in the temperature data Tmp is determined as the calculation period Tim.

[0008] Preferably, step S1 further includes: S17. Collect the initial anti-sliding force and sliding force from existing soil and rock test results, stability calculation data or historical calculation results of the cold region spoil heap, when it is not affected by the danger zone Dzb at the front edge of the thawing front, and transfer the initial anti-sliding force and the sliding force to the same calculation environment. S18. Match the initial anti-slip force and the sliding force according to the spatial position in the field model data Mod and the time order of the calculation period Tim. Define the matched initial anti-slip force as the initial anti-slip force Ini and the matched sliding force as the sliding force Drv. The anti-slip data Rst is composed of the initial anti-slip force Ini and the sliding force Drv. S19. The field model data Mod, the temperature data Tmp, the calculation time period Tim, and the anti-slip data Rst are unified in coordinates and time to form the basic dataset Bas.

[0009] Preferably, step S2 includes: S21. Call the field model data Mod, the temperature data Tmp, and the calculation time period Tim from the basic dataset Bas; S22. For each calculation unit Cel, multiply the temperature value greater than zero degrees Celsius within the corresponding calculation time period Tim by the corresponding acquisition time interval and sum them to obtain the positive temperature accumulation result Pta of the calculation unit Cel within the corresponding calculation time period Tim. Then multiply the positive temperature accumulation result Pta by the melting depth conversion coefficient Mdc to obtain the melting depth of the calculation unit Cel at the end of the corresponding calculation time period Tim. S23. Determine the spatial boundary point reached by the melting depth as the thawing boundary point, and combine the thawing boundary points corresponding to Tim in the same calculation period as the thawing front position Frt.

[0010] Preferably, step S3 includes: S31. Obtain the position Frt of the previous thawing front and the position Frt of the next thawing front when two adjacent calculation periods Tim terminate; S32. Determine the set of pre-fusion units Pre based on the thawing front position Frt described above, and determine the set of post-fusion units Lat based on the thawing front position Frt described below. Determine the computational units Cel that belong to the set of post-fusion units Lat but do not belong to the set of pre-fusion units Pre as the new unit set New. S33. The newly added unit set New is determined as the thawing front leading edge danger zone Dzb. If the newly added unit set New is empty, no new thawing front leading edge danger zone Dzb will be generated for the corresponding two adjacent calculation periods Tim.

[0011] Preferably, the process of determining the potential slip surface data Slp based on the field mode data Mod in the basic dataset Bas in step S4 includes: S41. Select the area between the top of the slope and the bottom of the slope in the field model data Mod as the search range of the slip surface. S42. Generate multiple candidate sliding surfaces within the sliding surface search range according to a preset search interval, define each candidate sliding surface as a candidate sliding surface Csl, and record the calculation unit Cel that each candidate sliding surface Csl continuously passes through; S43. The potential slip surface data Slp is composed of all candidate slip surfaces Csl and the calculation unit Cel that each candidate slip surface Csl passes through.

[0012] Preferably, the process of generating the overlapping data Ovd in step S4 includes: S44. For each candidate slip surface Csl in the potential slip surface data Slp, extract the overlapping slip surface segment Ovs where the candidate slip surface Csl passes through the thawing front leading danger zone Dzb; S45. Calculate the ratio between the length of the overlapping slip surface segment Ovs and the total length of the candidate slip surface Csl, or calculate the ratio between the area of ​​the overlapping slip surface segment Ovs and the total area of ​​the candidate slip surface Csl, and determine the ratio as the overlap ratio Ovr; S46. The overlap ratios Ovr corresponding to each candidate slip surface Csl are used to form the overlap data Ovd.

[0013] Preferably, the process of generating the modified anti-skid force Rsf in step S4 includes: S47. Based on the freeze-thaw test results, historical stability calculation results, or design values ​​of the cold region spoil heap, obtain the damage coefficient Dmg, and multiply the overlap ratio Ovr in the overlap data Ovd with the damage coefficient Dmg to obtain the anti-sliding reduction rate Rdr. S48. The result of subtracting the anti-slip reduction rate Rdr from one is determined as the reduction coefficient Red; S49. Multiply the initial anti-skid force Ini corresponding to the anti-skid data Rst in the basic dataset Bas by the reduction coefficient Red to obtain the corrected anti-skid force Rsf.

[0014] Preferably, step S5 includes: S51. Divide the modified anti-slip force Rsf corresponding to each candidate slip surface Csl in each calculation period Tim by the sliding force Drv corresponding to the anti-slip data Rst in the basic dataset Bas to obtain the corresponding safety factor Fsf. S52. The calculation period Tim with the smallest safety factor Fsf is determined as the dangerous period Rtm, and the overlapping area between the candidate slip surface Csl corresponding to the smallest safety factor Fsf and the dangerous zone Dzb of the thawing front corresponding to the calculation period Tim is determined as the dangerous area Rar. S53. The stability result Sta is composed of the dangerous period Rtm, the dangerous area Rar, the minimum safety factor Fsf, the corresponding candidate slip surface Csl, the corresponding overlapping data Ovd, and the corresponding thawing front leading edge danger zone Dzb.

[0015] This invention provides a quantitative calculation method for freeze-thaw damage stability of spoil heaps in cold regions, which has the following beneficial effects: (1) The impact of the thawing front that moves continuously during the spring thaw in the cold region spoil heap is identified separately from the overall freeze-thaw reduction. Overlapping data Ovd is formed by the tangential relationship between the dangerous zone Dzb at the front edge of the thawing front and the potential slip surface data Slp. This allows the safety factor Fsf to correspond to the specific calculation period Tim and the specific dangerous area. When the spring temperature rises and the surface of the slope thaws first while the deeper part remains frozen, the location where the anti-slip force is likely to decrease during the advancement of the thawing front Frt can be identified. By correcting the anti-slip force Rsf, a more stable result Sta that is closer to the actual instability risk during the spring thaw can be obtained, reducing the problems of delayed judgment of dangerous periods, deviation in the location of dangerous areas, and overestimation of the safety factor Fsf.

[0016] (2) The melting effect corresponding to the temperature data Tmp is converted into the thawing front position Frt at the end of each calculation period Tim, and the new unit set New is obtained by the set difference between the pre-melting unit set Pre and the post-melting unit set Lat, so that the thawing front danger zone Dzb has a clear spatial source; during the continuous warming period in spring, the newly entered calculation unit Cel can be directly determined as the thawing front danger zone Dzb, avoiding the expansion of the risk range by treating the entire melted area as a danger area, and also avoiding the omission of the concentrated area of ​​freeze-thaw damage that the thawing front position Frt has just advanced to.

[0017] (3) The influence of the thawing front leading danger zone Dzb on different candidate slip surfaces Csl is quantified from "whether it passes through the danger area" to the overlapping slip surface segment Ovs and the overlap ratio Ovr. The damage coefficient Dmg, the anti-slip reduction rate Rdr and the reduction coefficient Red are converted into the corrected anti-slip force Rsf, so that the safety factor Fsf reflects the stable state of each candidate slip surface Csl after being weakened by freeze-thaw damage under the corresponding calculation period Tim. When there are multiple candidate slip surfaces Csl in the same cold region spoil heap, the candidate slip surface Csl that is more affected by cutting can be distinguished according to the overlap ratio Ovr. The candidate slip surface Csl, danger period Rtm and danger area Rar corresponding to the minimum safety factor Fsf are written into the stability result Sta, reducing the misjudgment caused by judging the risk based solely on spatial proximity. Attached Figure Description

[0018] Figure 1 A schematic diagram of a method for quantitatively calculating the stability of freeze-thaw damage in spoil heaps in cold regions; Figure 2 A schematic diagram of the composition of the basic dataset Bas; Figure 3 A schematic diagram showing the correction to the overlap between the danger zone at the leading edge of the thawing front and the potential slip surface. Detailed Implementation

[0019] The technical solutions of the present invention will now be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention.

[0020] Example 1 In this embodiment, the application scenario is a spoil heap in an open-pit mine in a cold region. This spoil heap is frozen in winter due to the freezing effect of low temperatures. As the temperature rises, the thawed area gradually advances from the surface of the slope into the interior of the spoil heap. A thawing front position Frt is formed between the thawed and unthawed areas, which moves over time. If the thawing front position Frt cuts through the potential slip surface during its advancement, the cut area is prone to concentrated freeze-thaw damage, reduced slip resistance, and decreased safety factor. Therefore, this embodiment determines the spatial overlap between the dangerous zone Dzb at the leading edge of the thawing front and the potential slip surface data Slp to quantitatively calculate the stability of the spoil heap in a cold region under different calculation time periods Tim.

[0021] This invention provides a quantitative calculation method for freeze-thaw damage stability of spoil heaps in cold regions. Please refer to [link / reference]. Figure 1 This includes the following steps: S1. Obtain the field model data Mod, temperature data Tmp, and anti-sliding data Rst of the cold region spoil heap. According to the acquisition time order of the temperature data Tmp, determine the time interval between two adjacent acquisition times in the temperature data Tmp as the calculation time period Tim. Perform coordinate unification and time unification processing on the field model data Mod, temperature data Tmp, and anti-sliding data Rst to form the basic dataset Bas. S2. Based on the field model data Mod and temperature data Tmp in the basic dataset Bas, calculate the spatial boundary between the thawed and unthawed areas in the cold region spoil dump at the end of each calculation period Tim, and determine the spatial boundary as the thawing front position Frt of the corresponding calculation period Tim. S3. Based on the thawing front position Frt corresponding to the termination of two adjacent calculation periods Tim, extract the spatial area formed by the thawing front position Frt advancing into the cold region spoil dump between two adjacent calculation periods Tim, and determine this spatial area as the thawing front leading danger zone Dzb. S4. Based on the field model data Mod in the basic dataset Bas, determine the potential slip surface data Slp, calculate the spatial overlap relationship between the potential slip surface data Slp and the danger zone Dzb at the leading edge of the thawing front, generate the overlap data Ovd, and use the overlap data Ovd as the quantitative basis for the influence of freeze-thaw damage on the anti-slip force, correct the anti-slip force corresponding to the potential slip surface data Slp, and generate the corrected anti-slip force Rsf. S5. Calculate the safety factor Fsf based on the modified anti-skid force Rsf and the anti-skid data Rst in the basic dataset Bas, and generate a stable result Sta based on the safety factor Fsf corresponding to each calculation period Tim. The stable result Sta includes the dangerous period corresponding to the minimum safety factor Fsf and the dangerous area corresponding to the minimum safety factor Fsf.

[0022] In this embodiment, the above method can separately identify the impact of the continuously moving thawing front during the spring thaw in cold-region spoil heaps from the traditional overall freeze-thaw reduction. By forming overlapping data Ovd through the tangential relationship between the danger zone Dzb at the leading edge of the thawing front and the potential slip surface data Slp, the safety factor Fsf no longer only reflects the overall average stability of the spoil heap, but can also correspond to the specific calculation period Tim and specific danger areas. For example, when the surface of the slope thaws first after the spring temperature rises while the deeper parts remain frozen, this method can identify the location where the anti-slip force is most likely to decrease during the advancement of the thawing front Frt. By correcting the anti-slip force Rsf, a stability result Sta that is closer to the actual instability risk during the spring thaw can be obtained, thereby reducing the problems of delayed judgment of danger periods, deviation in the location of danger areas, and overestimation of the safety factor Fsf.

[0023] Example 2 This embodiment, based on embodiment 1, describes the acquisition, transmission, processing, and composition process of field modulus data Mod, temperature data Tmp, calculation time period Tim, anti-slip data Rst, and basic dataset Bas in step S1, so that the subsequent calculation of thawing front position Frt, thawing front leading edge danger zone Dzb, overlapping data Ovd, corrected anti-slip force Rsf, and safety factor Fsf has a clear data source.

[0024] Specifically: Step S1 includes: S11. Collect the spatial boundary, slope elevation, slope top line and slope toe line of the spoil heap from the existing surveying results or three-dimensional terrain model of the spoil heap in the cold region, and transfer the spatial boundary, slope elevation, slope top line and slope toe line of the spoil heap to the same computing environment. In the scenario set in Example 1, the spatial boundary, slope elevation, slope top line, and slope toe line of the spoil heap are derived from existing UAV oblique photography results, laser point cloud results, total station survey results, or designed three-dimensional terrain models in the mine. The implementers import the above results into the same data processing software, the same computing server, or the same database in the form of point cloud files, terrain grid files, contour line files, profile files, or three-dimensional model files, and retain the plane coordinates, elevation coordinates, data source, and collection batch of each point.

[0025] Specifically, the same computing environment means that the spatial boundary of the spoil heap, slope elevation, slope top line and slope toe line can be read and calculated in the same coordinate system, the same data format or mutually convertible data formats. If the file formats of data from different sources are different, they should be converted into point, line, surface or grid data formats that can be recognized by the same computing software before subsequent processing.

[0026] S12. Unify the coordinates of the spatial boundary, slope elevation, slope top line and slope toe line of the spoil heap, and divide it into multiple calculation units Cel according to the grid division method or the profile division method. Specifically, coordinate unification refers to transforming the spatial boundaries, slope elevations, top and bottom lines of the spoil heap into the existing unified coordinate system of the mine. If the existing surveying results and the 3D terrain model itself use the same coordinate system, their coordinate values ​​are directly read. If different data sources use different coordinate systems, the transformation is performed according to the coordinate transformation parameters recorded in the surveying results. If no coordinate transformation parameters are recorded, the coordinate transformation relationship is established using the control points that exist in different data sources, and the transformed coordinates are used as the coordinates for subsequent calculations.

[0027] In the data processing, the grid partitioning method is used for three-dimensional spatial calculation. The planar size of the calculation unit Cel is set according to the original grid size of the three-dimensional terrain model or an integer multiple thereof, and the same partitioning rules are maintained in the same calculation. The profile partitioning method is used for two-dimensional profile calculation. The implementer establishes the calculation profile along the direction from the top of the slope to the bottom of the slope, and divides the calculation profile into multiple calculation units Cel according to the original sampling interval of the profile or an integer multiple thereof.

[0028] It should be noted that the division result of the calculation unit Cel should cover the spoil heap slope area between the slope crest line and the slope toe line. Units located outside the spoil heap spatial boundary are not used as calculation units Cel. Units located on the spoil heap spatial boundary are retained for boundary calculation according to the intersection range with the spoil heap spatial boundary.

[0029] S13. Combine the position, elevation range and adjacency relationship of each calculation unit Cel with the spatial boundary of the spoil heap, slope elevation, slope top line and slope toe line to obtain the field model data Mod. Specifically, each computational cell (Cel) records the cell number, spatial location, elevation range, location of the slope to which it belongs, outer boundary, inner boundary, and adjacency relationship with surrounding computational cells (Cels). The spatial location is recorded using the coordinates of the center point or boundary node of the computational cell (Cel). The elevation range is recorded using the highest and lowest elevations of the computational cell (Cel). The adjacency relationship is recorded using the computational cell (Cel) numbers of shared boundaries, shared nodes, or shared surfaces.

[0030] In this embodiment, the field model data Mod consists of the waste dump spatial boundary, slope elevation, slope top line, slope toe line, and all calculation units Cel. The calculation units Cel in the field model data Mod are used to carry out the spatial location calculation of the subsequent thawing front position Frt, the thawing front leading danger zone Dzb, and the potential slip surface data Slp.

[0031] Step S1 further includes: S14. Collect a temperature sequence with collection time and temperature value from the existing temperature records of the cold region spoil heap, and transmit the temperature sequence to the same computing environment; In this embodiment, the temperature sequence is derived from existing meteorological stations in the mine, air temperature records from slope monitoring systems, ground temperature records, or historical meteorological data. Each data point in the temperature sequence includes the collection time, temperature value, and data source. The implementers import the temperature sequence into the same computing environment as the field model data Mod in the form of a table file, database record, data exported from the monitoring platform, or data read from the interface.

[0032] Specifically, the collection time is recorded using the same time base. If different temperature records are from different time bases, they are first converted to the same time base before being stored. Temperature values ​​are recorded using degrees Celsius as the uniform unit. If the original temperature values ​​are in other temperature units, they are first converted to degrees Celsius before being sorted and calculated. S15. Sort the temperature sequence according to the collection time from earliest to latest to obtain the temperature data Tmp; Specifically, before sorting, data records that lack collection time, lack temperature value, or whose temperature value cannot be identified as a numerical value are deleted. For data records with multiple temperature values ​​at the same collection time, their arithmetic mean is taken as the temperature value corresponding to that collection time. Then, the data are arranged from earliest to latest according to the collection time to form the temperature data Tmp.

[0033] During data processing, if there are data records in the temperature sequence that have repeated time order, reversed time order, or inconsistent acquisition time format, the acquisition time is first converted to a unified time format, and then reordered according to the unified time format so that any two adjacent records in the temperature data Tmp have a definite sequential order. S16. The time interval between two adjacent acquisition times in the temperature data Tmp is determined as the calculation period Tim.

[0034] Specifically, any two adjacent acquisition times in the temperature data Tmp form a calculation period Tim. The start of the calculation period Tim is the previous acquisition time, the end of the calculation period Tim is the next acquisition time, and the duration of the calculation period Tim is the time difference between the next acquisition time and the previous acquisition time.

[0035] In this embodiment, the calculation time period Tim is generated sequentially according to the time order of temperature data Tmp. The subsequent thawing front position Frt is calculated according to the end point of the calculation time period Tim. If the time interval between two adjacent collection times is different, the actual time interval is retained and used in the calculation of the subsequent positive temperature accumulation result Pta according to the corresponding actual time interval. Step S1 further includes: S17. Collect the initial anti-sliding force and sliding force from existing soil and rock test results, stability calculation data or historical calculation results of the cold region spoil heap, when it is not affected by the danger zone Dzb at the front edge of the thawing front, and transfer the initial anti-sliding force and the sliding force to the same calculation environment. In this embodiment, the initial anti-sliding force and the sliding force are derived from existing soil and rock test parameters in the mine, stability evaluation reports of the spoil heap, design calculations, or historical safety factor calculation results. The initial anti-sliding force corresponds to the anti-sliding capacity when the cutting effect of the dangerous zone Dzb at the leading edge of the thawing front is not considered, and the sliding force corresponds to the driving force generated by the sliding body along the sliding direction.

[0036] Specifically, if the initial anti-sliding force and sliding force are directly provided by existing data, then the initial anti-sliding force and sliding force are directly collected. If the initial anti-sliding force and safety factor are provided by existing data, then the initial anti-sliding force is divided by the safety factor to obtain the sliding force. If the rock and soil strength parameters and sliding body geometric parameters are provided by existing data, then the initial anti-sliding force and sliding force are calculated according to the existing stability calculation method, and the calculated initial anti-sliding force and sliding force are imported into the same calculation environment. S18. Match the initial anti-slip force and the sliding force according to the spatial position in the field model data Mod and the time order of the calculation period Tim. Define the matched initial anti-slip force as the initial anti-slip force Ini and the matched sliding force as the sliding force Drv. The anti-slip data Rst is composed of the initial anti-slip force Ini and the sliding force Drv. Specifically, if the initial anti-sliding force and sliding force correspond to a specific existing slip surface or a specific calculated profile, then the field model data Mod is matched according to the spatial location of the existing slip surface or the specific calculated profile. If the initial anti-sliding force and sliding force correspond to a spoil heap zone, then the spoil heap zone is first projected onto the calculation unit Cel in the field model data Mod, and then the corresponding initial anti-sliding force and sliding force are assigned to the calculation unit Cel in the spoil heap zone.

[0037] During data processing, if the initial anti-skid force and sliding force do not change over time, the initial anti-skid force and sliding force are assigned to all calculation periods Tim. If the initial anti-skid force and sliding force have time stamps, data records that are consistent with the end time of the calculation period Tim are selected first. If no data records with consistent time are found, data records that are no later than the end time of the calculation period Tim and are closest to the end time of the calculation period Tim are selected for matching.

[0038] It should be noted that the anti-slip data Rst consists of the initial anti-slip force Ini and the sliding force Drv after spatial and temporal matching are completed. The initial anti-slip force Ini and the sliding force Drv are called according to the calculation unit Cel that the candidate slip surface Csl passes through or the partition where the candidate slip surface Csl is located after the potential slip surface data Slp is generated. S19. Unify the coordinates and time of the field model data Mod, the temperature data Tmp, the calculation time period Tim, and the anti-slip data Rst to form the basic dataset Bas. Specifically, coordinate unification is used to ensure that the spatial locations of the calculation unit Cel, spoil heap spatial boundary, slope elevation, slope top line, slope toe line, and anti-sliding data Rst in the field model data Mod are in the same coordinate system. Time unification is used to ensure that the temperature data Tmp, calculation time period Tim, and anti-sliding data Rst can be called in the same time order.

[0039] In this embodiment, the basic dataset Bas consists of field model data Mod after coordinate and time unification, temperature data Tmp, calculation time period Tim, and anti-slip data Rst. Each callable record in the basic dataset Bas can correspond to the calculation unit Cel, the calculation time period Tim, and the initial anti-slip force Ini and the sliding force Drv in the anti-slip data Rst, so that the thawing front position Frt can be calculated step by step according to the calculation time period Tim and the anti-slip data Rst can be called according to the spatial position.

[0040] Through the above processing, implementers can form a basic dataset Bas that can be directly used for subsequent calculations from the existing surveying data, temperature records, and stability calculation data of the mine. This avoids problems such as inconsistent data sources, mismatched coordinates, or inability to retrieve time data when calculating the thawing front location Frt, the thawing front leading edge danger zone Dzb, overlapping data Ovd, corrected anti-slip force Rsf, and safety factor Fsf.

[0041] In this embodiment, through the data preparation process of Embodiment 2, the data of the cold region spoil heap, which was originally scattered in the surveying results, temperature records, geotechnical test results and historical stability calculation data, can be uniformly organized into the basic dataset Bas. This allows the field model data Mod, temperature data Tmp, calculation time period Tim, and anti-slip data Rst to be called in the same coordinate system and in the same time sequence. For example, when there are UAV terrain models, weather station thermometers and existing slope stability reports at the mine site, this embodiment can map the calculation unit Cel, temperature acquisition time, initial anti-slip force Ini, and sliding force Drv to the same calculation object. This avoids spatial misalignment, temporal mismatch, or the inability of the anti-slip data Rst to correspond to the specific potential slip surface when calculating the thawing front position Frt, the thawing front leading edge danger zone Dzb, and the safety factor Fsf.

[0042] Example 3 This embodiment, based on Embodiments 1 and 2, explains the calculation process of the thawing front position Frt in step S2 and the generation process of the thawing front leading edge danger zone Dzb in step S3. It enables implementers to obtain the thawing front position Frt at the end of each calculation period Tim based on the field model data Mod, temperature data Tmp, and calculation period Tim in the basic dataset Bas, and to determine the thawing front leading edge danger zone Dzb by adding a calculation unit Cel that enters the melting range between two adjacent thawing front positions Frt.

[0043] Specifically: Step S2 includes: S21. Call the field model data Mod, the temperature data Tmp, and the calculation time period Tim from the basic dataset Bas; In this embodiment, when calling the field model data Mod, the position, elevation range, adjacency relationship, and depth direction from the slope surface to the interior of the spoil heap are read for each calculation unit Cel. When calling the temperature data Tmp, the temperature value corresponding to each acquisition time is read. When calling the calculation period Tim, the start and end points of the calculation period Tim are read, and a correspondence is established between the temperature values ​​within the calculation period Tim and the calculation unit Cel. It should be noted that the depth direction from the slope surface to the interior of the spoil heap is determined based on the slope elevation and the position of the calculation unit Cel in the Mod data. When the profile segmentation method is used, the depth direction is the direction perpendicular or approximately perpendicular to the slope on the profile. When the grid segmentation method is used, the depth direction is the direction of the line connecting the grid surface node to the node inside the spoil heap. S22. For each calculation unit Cel, multiply the temperature value greater than zero degrees Celsius within the corresponding calculation time period Tim by the corresponding acquisition time interval and sum them to obtain the positive temperature accumulation result Pta of the calculation unit Cel within the corresponding calculation time period Tim. Then multiply the positive temperature accumulation result Pta by the melting depth conversion coefficient Mdc to obtain the melting depth of the calculation unit Cel at the end of the corresponding calculation time period Tim. Specifically, zero degrees Celsius is used as the calculation limit because the water-ice phase transition is based on zero degrees Celsius. Temperatures greater than zero degrees Celsius are included in the calculation of the positive temperature accumulation result Pta, while temperatures less than or equal to zero degrees Celsius are included in the calculation of the positive temperature accumulation result Pta as zero. During data processing, the acquisition time interval is the time difference between two adjacent acquisition times. The acquisition time interval is in hours, the temperature value is in degrees Celsius, the positive temperature accumulation result Pta is in degrees Celsius per hour, the melting depth conversion factor Mdc is in meters per degree Celsius per hour, and the melting depth obtained by multiplying the positive temperature accumulation result Pta by the melting depth conversion factor Mdc is in meters. In this embodiment, the melting depth conversion factor Mdc is determined before the calculation and remains unchanged in the same stability calculation. If there is a measured melting depth on site, the measured melting depth is divided by the positive temperature accumulation result Pta within the same time range to obtain the melting depth conversion factor Mdc. If there are multiple sets of measured melting depths, the melting depth conversion factor Mdc of each set is calculated separately and the arithmetic mean is taken as the melting depth conversion factor Mdc used in this calculation. If there is no measured melting depth on site, the melting depth conversion parameter given in the freeze-thaw test results of similar waste dumping materials or in the mine design data is used as the melting depth conversion factor Mdc. It should be noted that when the calculation period Tim is not the first calculation period Tim, the newly added melting depth obtained from the positive temperature accumulation result Pta and the melting depth conversion factor Mdc within the calculation period Tim is added to the melting depth already formed at the end of the previous calculation period Tim to obtain the melting depth at the end of the calculation period Tim. When there is no temperature value greater than zero degrees Celsius within the corresponding calculation period Tim, the newly added melting depth of the calculation period Tim is zero. S23. Determine the spatial boundary point reached by the melting depth as the thawing boundary point, and combine the thawing boundary points corresponding to the same calculation period Tim as the thawing front position Frt. Specifically, for each computational cell Cel, first determine the outer boundary depth and inner boundary depth of the computational cell Cel along the depth direction, and then compare the melting depth at the end of the computation time period Tim with the outer boundary depth and inner boundary depth of the computational cell Cel. During data processing, if the melting depth is less than the outer boundary depth of the calculation unit Cel, no thawing boundary point is generated for the calculation unit Cel. If the melting depth is between the outer boundary depth and the inner boundary depth of the calculation unit Cel, the position within the calculation unit Cel that is equal to the melting depth from the slope surface is determined as the thawing boundary point. If the melting depth is greater than or equal to the inner boundary depth of the calculation unit Cel, the inner boundary point of the calculation unit Cel is taken as the thawing boundary point. In this embodiment, all thawing boundary points within the same calculation period Tim are connected or combined according to their spatial coordinates to form a spatial boundary position between the thawed and unthawed areas, and this spatial boundary position is determined as the thawing front position Frt at the end of the calculation period Tim.

[0044] Step S3 includes: S31. Obtain the position Frt of the previous thawing front and the position Frt of the next thawing front when two adjacent calculation periods Tim terminate; In this embodiment, two consecutive calculation periods Tim are selected according to the time order of the calculation period Tim. The thawing front position Frt obtained when the calculation period Tim with the earlier time ends is taken as the previous thawing front position Frt, and the thawing front position Frt obtained when the calculation period Tim with the later time ends is taken as the next thawing front position Frt. It is confirmed that the previous thawing front position Frt and the next thawing front position Frt are both located in the same spatial coordinate system corresponding to the field model data Mod. It should be noted that if either of the two adjacent calculation time periods Tim does not generate the thawing front position Frt, the thawing front leading edge danger zone Dzb generation process will not be performed on the two adjacent calculation time periods Tim, and the next set of two adjacent calculation time periods Tim will be selected for processing. S32. Determine the set of pre-fusion units Pre based on the thawing front position Frt described above, and determine the set of post-fusion units Lat based on the thawing front position Frt described below. Determine the computational units Cel that belong to the set of post-fusion units Lat but do not belong to the set of pre-fusion units Pre as the new unit set New. Specifically, the set of pre-melting units Pre consists of computational units Cel contained in the melted area corresponding to the previous thawing front position Frt, and the set of subsequent melting units Lat consists of computational units Cel contained in the melted area corresponding to the next thawing front position Frt. The melted area refers to the spatial area located between the slope surface and the thawing front position Frt. During data processing, if the spatial range of the calculation unit Cel intersects with the fused region, the calculation unit Cel is included in the corresponding pre-fusion unit set Pre or post-fusion unit set Lat. If the spatial range of the calculation unit Cel does not intersect with the fused region, the calculation unit Cel is not included in the corresponding pre-fusion unit set Pre or post-fusion unit set Lat. It should be noted that performing set difference processing on the set of post-financing units Lat and the set of pre-financing units Pre means reading the computational units Cel in the set of post-financing units Lat one by one and determining whether the computational unit Cel exists in the set of pre-financing units Pre. If the computational unit Cel does not exist in the set of pre-financing units Pre, then the computational unit Cel is written to the set of new units New. If the computational unit Cel already exists in the set of pre-financing units Pre, then the computational unit Cel is not written to the set of new units New. S33. The newly added unit set New is determined as the thawing front leading edge danger zone Dzb. If the newly added unit set New is empty, no new thawing front leading edge danger zone Dzb will be generated in the corresponding two adjacent calculation periods Tim. Specifically, the computational unit Cel in the newly added unit set New corresponds to the spatial location of the newly entered melting range in the next computational period Tim. This spatial location is the spatial range covered by the thawing front position Frt advancing between two adjacent computational periods Tim. Therefore, the newly added unit set New is determined as the thawing front leading edge danger zone Dzb. In this embodiment, when the new unit set New is empty, it means that the position of the next thawing front Frt relative to the position of the previous thawing front Frt has not caused the new calculation unit Cel to enter the melting range. Therefore, Tim does not output a new thawing front leading edge danger zone Dzb for the two adjacent calculation periods. When the new unit set New is not empty, the spatial position, unit number and corresponding calculation period Tim of all calculation units Cel in the new unit set New are recorded together as the data content of the thawing front leading edge danger zone Dzb. Through the above processing, the danger zone Dzb at the leading edge of the thawing front is not directly specified by a fixed depth or a uniform reduction area, but is determined by the newly added calculation unit Cel that enters the melting range between two adjacent calculation periods Tim. This can reflect the mobile freeze-thaw damage concentration area formed by the thawing front position Frt over time.

[0045] In this embodiment, through the thawing front calculation and danger zone generation process of Embodiment 3, the melting effect corresponding to the temperature data Tmp can be transformed into the thawing front position Frt at the end of each calculation period Tim. Furthermore, the set of new units New is obtained by the set difference between the set of pre-melting units Pre and the set of post-melting units Lat, so that the danger zone Dzb at the front edge of the thawing front has a clear spatial source. For example, during the continuous warming period in spring, when the surface layer of the slope has melted in the previous calculation period Tim, and new calculation units Cel enter the melting range in the next calculation period Tim, this embodiment can directly determine these newly added calculation units Cel that have entered the melting range as the danger zone Dzb at the front edge of the thawing front, avoiding the expansion of the risk range by treating the entire melted area as a danger area, and also avoiding the omission of the concentrated area of ​​freeze-thaw damage that the thawing front position Frt has just advanced to.

[0046] Example 4 This embodiment, based on embodiments 1 to 3, explains the process of determining the potential slip surface data Slp in step S4, the process of generating the overlapping data Ovd, the process of generating the corrected anti-slip force Rsf, and the process of generating the safety factor Fsf and the stability result Sta in step S5. This allows the cutting effect of the thawing front leading danger zone Dzb on the candidate slip surface Csl to be transformed into the anti-slip force correction result and the stability calculation result.

[0047] Specifically, step S4, which involves determining the potential slip surface data Slp based on the field mode data Mod in the basic dataset Bas, includes: S41. Select the area between the top of the slope and the bottom of the slope in the field model data Mod as the search range of the slip surface. In this embodiment, the implementer reads the slope top line, slope toe line and calculation unit Cel in the field model data Mod, retains the calculation unit Cel located between the slope top line and the slope toe line and belonging to the interior of the spoil heap slope body as the slip surface search range, and excludes the calculation unit Cel located outside the spatial boundary of the spoil heap or not belonging to the interior of the slope body from the slip surface search range. S42. Generate multiple candidate sliding surfaces within the sliding surface search range according to a preset search interval, define each candidate sliding surface as a candidate sliding surface Csl, and record the calculation unit Cel that each candidate sliding surface Csl continuously passes through; Specifically, the preset search interval is set according to the size of the calculation unit Cel in the field model data Mod along the slope direction. The preset search interval is taken as the size of the calculation unit Cel along the slope direction or an integer multiple of the size of the calculation unit Cel along the slope direction. When it is necessary to improve the search accuracy, the size of the calculation unit Cel along the slope direction is taken. When it is necessary to reduce the amount of calculation, an integer multiple of the size of the calculation unit Cel along the slope direction is taken. The preset search interval remains unchanged in the same calculation. During data processing, the calculation unit Cel on the top of the slope is used as the starting control unit of the candidate slip surface Csl, and the calculation unit Cel on the bottom of the slope is used as the ending control unit of the candidate slip surface Csl. The starting control unit and the ending control unit are changed sequentially according to the preset search interval, and the calculation units Cel that pass continuously between the starting control unit and the ending control unit are connected within the slip surface search range, thereby generating multiple candidate slip surfaces Csl. S43. The potential slip surface data Slp is formed by combining all candidate slip surfaces Csl and the calculation unit Cel that each candidate slip surface Csl passes through. Specifically, each candidate slip surface Csl in the potential slip surface data Slp includes the candidate slip surface Csl number, the calculation unit Cel through which the candidate slip surface Csl continuously passes, the spatial path of the candidate slip surface Csl, and the total length or total area of ​​the candidate slip surface Csl, so that subsequent spatial overlap calculations can be performed on the candidate slip surface Csl and the thawing front leading danger zone Dzb.

[0048] The process of generating the overlapping data Ovd in step S4 includes: S44. For each candidate slip surface Csl in the potential slip surface data Slp, extract the overlapping slip surface segment Ovs where the candidate slip surface Csl passes through the thawing front leading danger zone Dzb; Specifically, the implementers will compare the calculation units Cel that the candidate slip surface Csl continuously passes through with the calculation units Cel contained in the thawing front hazard zone Dzb. The calculation units Cel that belong to both the candidate slip surface Csl and the thawing front hazard zone Dzb will be identified as overlapping units. The slip surface parts in the overlapping units will be connected according to the spatial path order of the candidate slip surface Csl to obtain the overlapping slip surface segment Ovs. It should be noted that when the same candidate slip surface Csl and the thawing front leading danger zone Dzb form multiple discontinuous overlapping parts, all of the multiple discontinuous overlapping parts are treated as components of the overlapping slip surface segment Ovs, and the multiple discontinuous overlapping parts are summed in subsequent length or area calculations. S45. Calculate the ratio between the length of the overlapping slip surface segment Ovs and the total length of the candidate slip surface Csl, or calculate the ratio between the area of ​​the overlapping slip surface segment Ovs and the total area of ​​the candidate slip surface Csl, and determine the ratio as the overlap ratio Ovr; Specifically, when the field model data Mod is calculated using a profile, the total length of the candidate slip surface Csl is the sum of the lengths of the continuous line segments of the candidate slip surface Csl within the profile, the length of the overlapping slip surface segment Ovs is the sum of the lengths of the continuous line segments of the overlapping slip surface segment Ovs within the profile, and the overlap ratio Ovr is obtained by dividing the length of the overlapping slip surface segment Ovs by the total length of the candidate slip surface Csl. In this embodiment, when the field model data Mod is calculated in three-dimensional space, the total area of ​​the candidate slip surface Csl is the sum of the areas of the spatial patches corresponding to the candidate slip surface Csl, the area of ​​the overlapping slip surface segment Ovs is the sum of the areas of the spatial patches corresponding to the overlapping slip surface segment Ovs, and the overlap ratio Ovr is obtained by dividing the area of ​​the overlapping slip surface segment Ovs by the total area of ​​the candidate slip surface Csl; S46. The overlap ratios Ovr corresponding to each candidate slip surface Csl are used to form the overlap data Ovd; Specifically, the overlapping data Ovd is stored according to the calculation period Tim and the candidate slip surface Csl. Each piece of overlapping data Ovd includes a calculation period Tim, a candidate slip surface Csl, and the overlap ratio Ovr of the candidate slip surface Csl under the calculation period Tim. When the candidate slip surface Csl does not overlap with the thawing front leading edge danger zone Dzb, the overlap ratio Ovr of the candidate slip surface Csl is recorded as zero.

[0049] The process of generating the modified anti-slip force Rsf in step S4 includes: S47. Based on the freeze-thaw test results, historical stability calculation results, or design values ​​of the cold region spoil heap, obtain the damage coefficient Dmg, and multiply the overlap ratio Ovr in the overlap data Ovd with the damage coefficient Dmg to obtain the anti-sliding reduction rate Rdr. Specifically, the damage coefficient Dmg is used to represent the reduction strength of anti-slip force due to freeze-thaw damage within the danger zone Dzb at the leading edge of the thawing front. The value of the damage coefficient Dmg is not less than zero and not greater than one, where zero indicates that no reduction of anti-slip force occurs within the danger zone Dzb at the leading edge of the thawing front, and one indicates that the anti-slip force of the corresponding part within the danger zone Dzb at the leading edge of the thawing front is completely reduced. In this embodiment, if freeze-thaw test results for cold-region spoil heaps exist, the damage coefficient Dmg is determined based on the ratio of the difference between the anti-sliding force before and after freeze-thaw of similar spoil heap materials to the anti-sliding force before freeze-thaw. If freeze-thaw test results for cold-region spoil heaps do not exist, the freeze-thaw reduction rate already used in the historical stability calculation results is used as the damage coefficient Dmg. If neither of the above two types of data exists, the freeze-thaw reduction value given for similar spoil heap materials in the mine design documents or stability evaluation report is used as the damage coefficient Dmg. During data processing, the anti-slip reduction ratio Rdr is obtained by multiplying the overlap ratio Ovr by the damage coefficient Dmg. When the overlap ratio Ovr is zero, the anti-slip reduction ratio Rdr is zero. When the overlap ratio Ovr is one, the anti-slip reduction ratio Rdr is equal to the damage coefficient Dmg. Thus, the anti-slip reduction ratio Rdr only affects the part of the candidate slip surface Csl that is cut through by the danger zone Dzb at the leading edge of the thawing front. S48. The result of subtracting the anti-slip reduction ratio Rdr from one is determined as the reduction coefficient Red; Specifically, the reduction factor Red represents the proportion of anti-slip force retained by the candidate slip surface Csl under the corresponding calculation time Tim. Since the values ​​of the overlap ratio Ovr and the damage coefficient Dmg are both between zero and one, and the anti-slip reduction rate Rdr is also between zero and one, the value of the reduction factor Red is also between zero and one.

[0050] S49. Multiply the initial anti-skid force Ini corresponding to the anti-skid data Rst in the basic dataset Bas by the reduction coefficient Red to obtain the corrected anti-skid force Rsf; Specifically, the initial anti-slip force Ini corresponds to the anti-slip force of the candidate slip surface Csl when it is not affected by the danger zone Dzb at the leading edge of the thawing front. The modified anti-slip force Rsf corresponds to the anti-slip force of the same candidate slip surface Csl after deducting the impact of the danger zone Dzb cutting through it under the corresponding calculation time period Tim. The implementers calculate and store the modified anti-slip force Rsf one by one according to the calculation time period Tim and the candidate slip surface Csl.

[0051] Step S5 includes: S51. Divide the modified anti-slip force Rsf corresponding to each candidate slip surface Csl in each calculation period Tim by the sliding force Drv corresponding to the anti-slip data Rst in the basic dataset Bas to obtain the corresponding safety factor Fsf. Specifically, the sliding force Drv is set to correspond with the candidate slip surface Csl. For the same candidate slip surface Csl and the same calculation time period Tim, the implementers call the modified anti-slip force Rsf and the sliding force Drv, and divide the modified anti-slip force Rsf by the sliding force Drv to obtain the safety factor Fsf. When the sliding force Drv is zero, the candidate slip surface Csl is not used as a valid slip surface to participate in the safety factor Fsf ranking.

[0052] S52. The calculation period Tim with the smallest safety factor Fsf is determined as the dangerous period Rtm, and the overlapping area between the candidate slip surface Csl corresponding to the smallest safety factor Fsf and the dangerous zone Dzb of the thawing front corresponding to the calculation period Tim is determined as the dangerous area Rar. Specifically, the implementers will compile the safety factors Fsf corresponding to all calculation time periods Tim and all candidate slip surfaces Csl into a safety factor sequence, and sort them in ascending order of safety factor Fsf. The calculation time period Tim corresponding to the safety factor Fsf that is ranked first after sorting will be determined as the dangerous time period Rtm. The spatial overlap between the candidate slip surface Csl corresponding to the safety factor Fsf that is ranked first after sorting and the corresponding thawing front leading edge danger zone Dzb will be determined as the danger area Rar. It should be noted that when there are multiple safety factors Fsf with the same minimum value, the calculation period Tim corresponding to all multiple safety factors Fsf with the same minimum value is determined as the dangerous period Rtm, and the spatially overlapping parts corresponding to multiple safety factors Fsf with the same minimum value are determined as the dangerous area Rar. S53. The stability result Sta is composed of the dangerous period Rtm, the dangerous area Rar, the minimum safety factor Fsf, the corresponding candidate slip surface Csl, the corresponding overlapping data Ovd, and the corresponding thawing front leading danger zone Dzb. Specifically, the stabilization results Sta are output in the form of tables, spatial layers, or calculation reports. Each result record in the stabilization results Sta includes the danger period Rtm, danger area Rar, minimum safety factor Fsf, corresponding candidate slip surface Csl, corresponding overlapping data Ovd, and corresponding hazard zone Dzb at the leading edge of the thawing front. This enables implementers to directly determine the time and spatial location of the cold region spoil heap with the lowest safety factor and the corresponding slip surface object during the advance of the thawing front.

[0053] In this embodiment, through the potential slip surface overlap calculation and anti-slip force correction process of Example 4, the influence of the thawing front leading danger zone Dzb on different candidate slip surfaces Csl can be further quantified from "whether it passes through the danger zone" to the overlapping slip surface segment Ovs and the overlap ratio Ovr. This cutting effect is then converted into a corrected anti-slip force Rsf using the damage coefficient Dmg, the anti-slip reduction rate Rdr, and the reduction coefficient Red, so that the safety factor Fsf can reflect the freeze-thaw damage suffered by each candidate slip surface Csl under the corresponding calculation time period Tim. The true stable state after weakening; for example, when there are multiple candidate slip surfaces Csl in the same cold region spoil heap, even if they are all close to the danger zone Dzb at the front edge of the thawing front, this embodiment can also distinguish which candidate slip surface Csl is more affected by the cutting through based on the overlap ratio Ovr, and write the candidate slip surface Csl corresponding to the minimum safety factor Fsf, the danger period Rtm, and the danger area Rar into the stability result Sta, thereby avoiding judging the risk based solely on spatial proximity, and being able to more accurately determine the slip surface and treatment area that needs the most attention during the spring thaw.

[0054] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A quantitative calculation method for freeze-thaw damage stability of spoil heaps in cold regions, characterized in that: Includes the following steps: S1. Obtain the field model data Mod, temperature data Tmp, and anti-sliding data Rst of the cold region spoil heap. According to the acquisition time order of the temperature data Tmp, determine the time interval between two adjacent acquisition times in the temperature data Tmp as the calculation time period Tim. Perform coordinate unification and time unification processing on the field model data Mod, temperature data Tmp, and anti-sliding data Rst to form the basic dataset Bas. S2. Based on the field model data Mod and temperature data Tmp in the basic dataset Bas, calculate the spatial boundary between the thawed and unthawed areas in the cold region spoil dump at the end of each calculation period Tim, and determine the spatial boundary as the thawing front position Frt of the corresponding calculation period Tim. S3. Based on the thawing front position Frt corresponding to the termination of two adjacent calculation periods Tim, extract the spatial area formed by the thawing front position Frt advancing into the cold region spoil dump between two adjacent calculation periods Tim, and determine this spatial area as the thawing front leading danger zone Dzb. S4. Based on the field model data Mod in the basic dataset Bas, determine the potential slip surface data Slp, calculate the spatial overlap relationship between the potential slip surface data Slp and the danger zone Dzb at the leading edge of the thawing front, generate the overlap data Ovd, and use the overlap data Ovd as the quantitative basis for the influence of freeze-thaw damage on the anti-slip force, correct the anti-slip force corresponding to the potential slip surface data Slp, and generate the corrected anti-slip force Rsf. S5. Calculate the safety factor Fsf based on the modified anti-skid force Rsf and the anti-skid data Rst in the basic dataset Bas, and generate a stable result Sta based on the safety factor Fsf corresponding to each calculation period Tim. The stable result Sta includes the dangerous period corresponding to the minimum safety factor Fsf and the dangerous area corresponding to the minimum safety factor Fsf.

2. The method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions according to claim 1, characterized in that: Step S1 includes: S11. Collect the spatial boundary, slope elevation, slope top line and slope toe line of the spoil heap from the existing surveying results or three-dimensional terrain model of the spoil heap in the cold region, and transfer the spatial boundary, slope elevation, slope top line and slope toe line of the spoil heap to the same computing environment. S12. Unify the coordinates of the spatial boundary, slope elevation, slope top line and slope toe line of the spoil heap, and divide it into multiple calculation units Cel according to the grid division method or the profile division method. S13. Combine the position, elevation range, and adjacency relationship of each calculation unit Cel with the spatial boundary of the spoil heap, slope elevation, slope top line, and slope toe line to obtain the field model data Mod.

3. The method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions according to claim 2, characterized in that: Step S1 further includes: S14. Collect a temperature sequence with collection time and temperature value from the existing temperature records of the cold region spoil heap, and transmit the temperature sequence to the same computing environment; S15. Sort the temperature sequence according to the collection time from earliest to latest to obtain the temperature data Tmp; S16. The time interval between two adjacent acquisition times in the temperature data Tmp is determined as the calculation period Tim.

4. The method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions according to claim 3, characterized in that: Step S1 further includes: S17. Collect the initial anti-sliding force and sliding force from existing soil and rock test results, stability calculation data or historical calculation results of the cold region spoil heap, when it is not affected by the danger zone Dzb at the front edge of the thawing front, and transfer the initial anti-sliding force and the sliding force to the same calculation environment. S18. Match the initial anti-slip force and the sliding force according to the spatial position in the field model data Mod and the time order of the calculation period Tim. Define the matched initial anti-slip force as the initial anti-slip force Ini and the matched sliding force as the sliding force Drv. The anti-slip data Rst is composed of the initial anti-slip force Ini and the sliding force Drv. S19. The field model data Mod, the temperature data Tmp, the calculation time period Tim, and the anti-slip data Rst are unified in coordinates and time to form the basic dataset Bas.

5. The method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions according to claim 4, characterized in that: Step S2 includes: S21. Call the field model data Mod, the temperature data Tmp, and the calculation time period Tim from the basic dataset Bas; S22. For each calculation unit Cel, multiply the temperature value greater than zero degrees Celsius within the corresponding calculation time period Tim by the corresponding acquisition time interval and sum them to obtain the positive temperature accumulation result Pta of the calculation unit Cel within the corresponding calculation time period Tim. Then multiply the positive temperature accumulation result Pta by the melting depth conversion coefficient Mdc to obtain the melting depth of the calculation unit Cel at the end of the corresponding calculation time period Tim. S23. Determine the spatial boundary point reached by the melting depth as the thawing boundary point, and combine the thawing boundary points corresponding to Tim in the same calculation period as the thawing front position Frt.

6. The method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions according to claim 5, characterized in that: Step S3 includes: S31. Obtain the position Frt of the previous thawing front and the position Frt of the next thawing front when two adjacent calculation periods Tim terminate; S32. Determine the set of pre-fusion units Pre based on the thawing front position Frt described above, and determine the set of post-fusion units Lat based on the thawing front position Frt described below. Determine the computational units Cel that belong to the set of post-fusion units Lat but do not belong to the set of pre-fusion units Pre as the new unit set New. S33. The newly added unit set New is determined as the thawing front leading edge danger zone Dzb. If the newly added unit set New is empty, no new thawing front leading edge danger zone Dzb will be generated for the corresponding two adjacent calculation periods Tim.

7. The method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions according to claim 6, characterized in that: The process of determining the potential slip surface data Slp based on the field mode data Mod in the basic dataset Bas in step S4 includes: S41. Select the area between the top of the slope and the bottom of the slope in the field model data Mod as the search range of the slip surface. S42. Generate multiple candidate sliding surfaces within the sliding surface search range according to a preset search interval, define each candidate sliding surface as a candidate sliding surface Csl, and record the calculation unit Cel that each candidate sliding surface Csl continuously passes through; S43. The potential slip surface data Slp is formed by combining all candidate slip surfaces Csl and the calculation unit Cel that each candidate slip surface Csl passes through.

8. The method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions according to claim 7, characterized in that: The process of generating the overlapping data Ovd in step S4 includes: S44. For each candidate slip surface Csl in the potential slip surface data Slp, extract the overlapping slip surface segment Ovs where the candidate slip surface Csl passes through the thawing front leading edge danger zone Dzb; S45. Calculate the ratio between the length of the overlapping slip surface segment Ovs and the total length of the candidate slip surface Csl, or calculate the ratio between the area of ​​the overlapping slip surface segment Ovs and the total area of ​​the candidate slip surface Csl, and determine the ratio as the overlap ratio Ovr; S46. The overlap ratios Ovr corresponding to each candidate slip surface Csl are used to form the overlap data Ovd.

9. The method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions according to claim 8, characterized in that: The process of generating the modified anti-slip force Rsf in step S4 includes: S47. Based on the freeze-thaw test results, historical stability calculation results, or design values ​​of the cold region spoil heap, obtain the damage coefficient Dmg, and multiply the overlap ratio Ovr in the overlap data Ovd with the damage coefficient Dmg to obtain the anti-sliding reduction rate Rdr. S48. The result of subtracting the anti-slip reduction ratio Rdr from one is determined as the reduction coefficient Red; S49. Multiply the initial anti-skid force Ini corresponding to the anti-skid data Rst in the basic dataset Bas by the reduction coefficient Red to obtain the modified anti-skid force Rsf.

10. The method for quantitatively calculating the freeze-thaw damage stability of spoil heaps in cold regions according to claim 9, characterized in that: Step S5 includes: S51. Divide the modified anti-slip force Rsf corresponding to each candidate slip surface Csl in each calculation period Tim by the sliding force Drv corresponding to the anti-slip data Rst in the basic dataset Bas to obtain the corresponding safety factor Fsf. S52. The calculation period Tim with the smallest safety factor Fsf is determined as the dangerous period Rtm, and the overlapping area between the candidate slip surface Csl corresponding to the smallest safety factor Fsf and the dangerous zone Dzb of the thawing front corresponding to the calculation period Tim is determined as the dangerous area Rar. S53. The stability result Sta is composed of the dangerous period Rtm, the dangerous area Rar, the minimum safety factor Fsf, the corresponding candidate slip surface Csl, the corresponding overlapping data Ovd, and the corresponding thawing front leading edge danger zone Dzb.

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