Method and device for determining back pressure platform for preventing and treating coal fire area of strip mine

Abstract

The invention provides a method and a device for determining a back pressure platform for preventing and treating a coal fire area of a strip mine, and relates to the technical field of prevention and treatment of the coal fire area of the strip mine. Firstly, according to a Coulomb soil pressure theory, geometric parameters of a two-dimensional section of a composite slope of a dumping site and physical and mechanical parameters of a discharged soil body, soil pressure of a soil-rock contact surface is calculated; then, in order to weaken the shearing effect of the composite side slope of the waste dump on the slope toe area, the soil heaping amount required by a back pressure platform arranged at the slope toe of the composite side slope of the waste dump when the extension size of the back pressure platform in the three-dimensional space is 1 meter is calculated; the slope angle of the platform is the slope angle of the side slope of the dump and is used as a geometrical shape condition of the slope toe back pressure platform, and geometrical parameters of the slope toe back pressure platform are calculated according to the soil heaping amount. The method is low in implementation cost, the shear effect of the side slope of the waste dump on the slope toe is weakened, displacement of the soil body and the rock stratum at the slope toe is restrained, crack development is reduced, air permeability is reduced, and coal seam combustion and spreading are effectively restrained.

Description

Technical Field

[0001] The present invention relates to the technical field of prevention and control of coal fire areas in open-pit mines, and particularly to a method and device for determining a backpressure platform for preventing and controlling coal fire areas in open-pit mines. Background Art

[0002] A coal fire refers to the combustion or smoldering of surface or underground coal seams without external control. With the spread and expansion of coal fires, the surrounding rock strata are thermally metamorphosed under the action of high temperatures for a long time and become burned rocks, eventually forming a coal fire area. Coal fire areas are relatively common in arid regions in the northwest. Due to the high temperature and dryness in summer, outcrop coal seams and shallowly buried coal seams are extremely prone to spontaneous combustion. After the formation of a coal fire area, it usually interacts with factors such as slope stability and groundwater, which may induce a series of geological disasters and threaten the safety of mine production. During the open-pit mining process, waste soil is piled up along the non-working slope in the stope. When the height of the piled soil exceeds the ground surface, a reverse composite slope is formed. Such slopes often exert a strong shearing effect on the toe area (i.e., the top position of the mining slope), resulting in the rupture of the overlying rock strata of the coal seam, generating a large number of fissures. Coupled with high-temperature weather, a coal fire area is induced at this position, which is a dump slope-induced coal fire area. Such coal fire areas are close to the dump slope, and their spread and expansion will weaken the stability of the dump slope and increase the risk of landslides. Therefore, it is necessary to timely and effectively control such coal fire areas to ensure the safety of open-pit mine production.

[0003] In terms of the control measures for coal fire areas, common methods in the prior art include: water and soil filling, excavation, liquid carbon dioxide fire extinguishing, etc. Although the above methods are widely used, the implementation costs are relatively high. Summary of the Invention

[0004] The purpose of the present invention is to provide a method and device for determining a backpressure platform for preventing and controlling coal fire areas in open-pit mines, so as to alleviate the technical problem of relatively high implementation costs existing in the prior art for the control methods of coal fire areas in open-pit mines.

[0005] In a first aspect, the present invention provides a method for determining a counter-pressure platform for preventing and controlling coal fire areas in open-pit mines, including: obtaining the geometric parameters of the two-dimensional profile of the waste dump composite slope and the physical and mechanical parameters of the dumped soil mass; wherein, the geometric parameters include: the angle between the soil-rock contact surface and the vertical line, the slope angle of the waste dump slope, and the retaining wall height; the physical and mechanical parameters include: soil unit weight, soil internal friction angle, soil-rock contact surface friction angle, and soil cohesion; based on the Coulomb earth pressure theory, geometric parameters, and physical and mechanical parameters, calculate the earth pressure on the soil-rock contact surface; based on the earth pressure on the soil-rock contact surface, the soil-rock contact surface friction angle, the angle between the soil-rock contact surface and the vertical line, and the soil unit weight, calculate the amount of soil to be piled when the extension dimension of the toe counter-pressure platform in three-dimensional space is 1 meter; wherein, the toe counter-pressure platform is used to weaken the shearing effect of the waste dump composite slope on the toe area; taking the two-dimensional profile as a parallelogram and the platform slope angle as the slope angle of the waste dump slope as the geometric shape condition of the toe counter-pressure platform, and based on the amount of piled soil, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line, calculate the geometric parameters of the toe counter-pressure platform.

[0006] In an alternative embodiment, based on the Coulomb earth pressure theory, geometric parameters, and physical and mechanical parameters, calculating the earth pressure on the soil-rock contact surface includes: processing the soil unit weight, soil internal friction angle, soil cohesion, and retaining wall height by using the equivalent internal friction angle method to obtain the equivalent internal friction angle of the soil mass; based on the angle between the soil-rock contact surface and the vertical line, the soil-rock contact surface friction angle, the equivalent internal friction angle of the soil mass, and the slope angle of the waste dump slope, calculate the angle between the internal sliding surface of the dumped soil mass and the horizontal plane; based on the preset angle critical value and the angle between the internal sliding surface of the dumped soil mass and the horizontal plane, use the Coulomb earth pressure theory to calculate the earth pressure on the soil-rock contact surface.

[0007] In an alternative embodiment, based on the preset angle critical value and the angle between the internal sliding surface of the dumped soil mass and the horizontal plane, using the Coulomb earth pressure theory to calculate the earth pressure on the soil-rock contact surface includes: when the angle between the internal sliding surface of the dumped soil mass and the horizontal plane is greater than or equal to the preset angle critical value, determining that the filling surface of the sliding soil mass is a flat filling surface; based on the equivalent internal friction angle of the soil mass, the angle between the soil-rock contact surface and the vertical line, the soil-rock contact surface friction angle, and the slope angle of the waste dump slope, calculate the active earth pressure coefficient when the filling surface of the sliding soil mass is a flat filling surface; based on the active earth pressure coefficient, the soil unit weight, and the retaining wall height, calculate the first active earth pressure; taking the first active earth pressure as the earth pressure on the soil-rock contact surface.

[0008] In an alternative embodiment, based on a preset critical angle value and the angle between the internal sliding surface of the discharged soil mass and the horizontal plane, the earth pressure at the soil-rock contact surface is calculated using the Coulomb earth pressure theory, and further includes: in the case where the angle between the internal sliding surface of the discharged soil mass and the horizontal plane is less than the preset critical angle value, determining that the filling surface of the sliding soil mass is a broken-line filling surface; converting the broken-line filling surface into a flat filling surface to calculate the equivalent retaining wall height of the corresponding triangular equivalent sliding soil mass; determining an equivalent coefficient of the retaining wall height based on the retaining wall height and the equivalent retaining wall height; calculating the second active earth pressure when the filling surface of the sliding soil mass is a broken-line filling surface based on the equivalent coefficient of the retaining wall height and the first active earth pressure; and taking the second active earth pressure as the earth pressure at the soil-rock contact surface.

[0009] In an alternative embodiment, converting the broken-line filling surface into a flat filling surface to calculate the equivalent retaining wall height of the corresponding triangular equivalent sliding soil mass includes: determining the quadrilateral actual sliding soil mass in the discharged soil mass based on the angle between the internal sliding surface of the discharged soil mass and the horizontal plane; converting the quadrilateral actual sliding soil mass into a triangular equivalent sliding soil mass with a flat filling surface; and calculating the equivalent retaining wall height of the triangular equivalent sliding soil mass on the condition that the area of the actual sliding soil mass is equal to the area of the triangular equivalent sliding soil mass.

[0010] In an alternative embodiment, based on the earth pressure at the soil-rock contact surface, the friction angle of the soil-rock contact surface, the angle between the soil-rock contact surface and the vertical line, and the unit weight of the soil, the amount of soil stacking required when the three-dimensional extension dimension of the toe counterweight platform is 1 m is calculated, including: calculating the frictional force applied to the rock mass block when the compound slope of the waste dump has a circular sliding tendency based on the earth pressure at the soil-rock contact surface and the friction angle of the soil-rock contact surface; and calculating the amount of soil stacking required when the three-dimensional extension dimension of the toe counterweight platform is 1 m based on the frictional force, the angle between the soil-rock contact surface and the vertical line, and the unit weight of the soil on the condition that the forces on the soil-rock contact surface are in balance.

[0011] In an alternative embodiment, based on the amount of soil stacking, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line, the geometric parameters of the toe counterweight platform are calculated, including: calculating the height of the toe counterweight platform based on the amount of soil stacking, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line; and calculating the width of the toe counterweight platform based on the amount of soil stacking and the height of the toe counterweight platform.

[0012] Second aspect, the present invention provides an anti-pressure platform determination device for preventing and controlling coal fire areas in open-pit mines, including: an acquisition module, configured to acquire the geometric parameters of the two-dimensional profile of the waste dump composite slope and the physical and mechanical parameters of the dumped soil mass; wherein, the geometric parameters include: the angle between the soil-rock contact surface and the vertical line, the slope angle of the waste dump slope, and the retaining wall height; the physical and mechanical parameters include: soil unit weight, soil internal friction angle, soil-rock contact surface friction angle, and soil cohesion; a first calculation module, configured to calculate the soil pressure on the soil-rock contact surface based on the Coulomb earth pressure theory, geometric parameters, and physical and mechanical parameters; a second calculation module, configured to calculate the amount of piled soil required when the extension dimension of the toe anti-pressure platform in the three-dimensional space is 1 meter based on the soil pressure on the soil-rock contact surface, the soil-rock contact surface friction angle, the angle between the soil-rock contact surface and the vertical line, and the soil unit weight; wherein, the toe anti-pressure platform is used to weaken the shear action of the waste dump composite slope on the toe area; a third calculation module, configured to take the two-dimensional profile as a parallelogram and the platform slope angle as the slope angle of the waste dump slope as the geometric shape condition of the toe anti-pressure platform, and calculate the geometric parameters of the toe anti-pressure platform based on the amount of piled soil, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line.

[0013] Third aspect, the present invention provides an electronic device, including a memory and a processor, where a computer program executable on the processor is stored on the memory, and when the processor executes the computer program, it implements the anti-pressure platform determination method for preventing and controlling coal fire areas in open-pit mines according to any one of the foregoing embodiments.

[0014] Fourth aspect, the present invention provides a computer-readable storage medium, where computer instructions are stored, and when the computer instructions are executed by a processor, they implement the anti-pressure platform determination method for preventing and controlling coal fire areas in open-pit mines according to any one of the foregoing embodiments.

[0015] Regarding the problem of treating induced coal fire areas in waste dumps, the present invention proposes to set a counter-pressure platform at the toe of the slope as a treatment measure. First, based on the Coulomb earth pressure theory, the geometric parameters of the two-dimensional profile of the composite slope of the waste dump, and the physical and mechanical parameters of the dumped soil mass, the earth pressure at the soil-rock contact surface is calculated. Then, aiming to weaken the shear action of the composite slope of the waste dump on the toe area, the soil stacking volume required when the three-dimensional extension dimension of the counter-pressure platform set at the toe of the composite slope of the waste dump is 1 meter is calculated. Finally, with the two-dimensional profile being a parallelogram and the platform slope angle being the slope angle of the waste dump slope as the geometric shape condition of the toe counter-pressure platform, the geometric parameters of the toe counter-pressure platform are calculated according to the soil stacking volume, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line. The method of setting a counter-pressure platform at the toe of the waste dump slope in the present invention, on the one hand, can improve the slope stability; on the other hand, it can weaken the shear action of the waste dump slope on the toe, inhibit the displacement of the soil and rock layers at the toe, reduce the development of fissures, and lower the air permeability, thereby effectively curbing the combustion and spread of the coal seam. Compared with other coal fire treatment measures, this method has a lower cost and a simple and feasible construction process, and has a wide application prospect. In addition, before the formation of the coal fire area, a counter-pressure platform can be constructed in advance as a preventive measure, thereby effectively reducing the occurrence risk of the coal fire area. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0017] Figure 1 It is a flowchart of a method for determining a counter-pressure platform for preventing and controlling coal fire areas in open-pit mines provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of a two-dimensional profile of a composite slope of a waste dump provided by an embodiment of the present invention; Figure 3 It is a schematic diagram of the common geometric shapes of the soil mass piled up at the toe of the slope; Figure 4 It is a soil pressure calculation model diagram based on the two-dimensional profile of the composite slope of the waste dump provided by an embodiment of the present invention; Figure 5 It is a calculation model diagram of the toe counter-pressure platform provided by an embodiment of the present invention; Figure 6 It is a schematic diagram of a slope numerical analysis model and the position of the monitoring line provided by an embodiment of the present invention; Figure 7 It is a displacement distribution characteristic diagram of each monitoring line before the toe counter-pressure platform is set; Figure 8 It is the displacement distribution characteristic diagram of the monitoring line after the anti - pressure platform at the toe of the slope is set; Figure 9 It is the functional module diagram of an anti - pressure platform determination device for preventing and controlling the coal fire area in open - pit mines provided by an embodiment of the present invention; Figure 10 It is the schematic diagram of an electronic device provided by an embodiment of the present invention. Specific embodiments

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Generally, the components of the embodiments of the present invention described and illustrated here can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0020] The following will describe in detail some embodiments of the present invention with reference to the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0021] Regarding the treatment problem of the induced coal fire area in the waste dump, an embodiment of the present invention proposes to set an anti - pressure platform at the toe of the waste dump slope as a treatment measure. The traditional treatment of the toe of the waste dump slope is mainly used to improve the slope stability, and its design usually takes the slope safety factor as the optimization goal to determine the amount of soil piled at the toe and the geometric parameters of the anti - pressure platform. However, the design of the anti - pressure platform in the embodiment of the present invention aims to weaken the shear action of the waste dump slope on the shallow rock stratum at the toe, thereby inhibiting the expansion of the coal fire area. Due to the different goals of the toe - pressing design, the determination criteria for the amount of soil piled at the toe are also different. The embodiment of the present invention needs to deduce the geometric parameters of the anti - pressure platform at the toe of the slope based on the earth pressure theory to achieve the corresponding treatment effect.

[0022] Embodiment 1 Figure 1 It is the flowchart of an anti - pressure platform determination method for preventing and controlling the coal fire area in open - pit mines provided by an embodiment of the present invention. As Figure 1 shown, the method specifically includes the following steps: Step S102, obtain the geometric parameters of the two - dimensional profile of the composite slope of the waste dump and the physical and mechanical parameters of the dumped soil mass.

[0023] For the convenience of theoretical calculation and the application of the Coulomb earth pressure theory, the following assumptions need to be made for the implementation of the embodiments of the present invention: The sliding soil mass is regarded as a rigid body and is in a state of limit equilibrium; when calculating the active earth pressure, the sliding surface is assumed to be a plane; in view of the research focus on the stress characteristics of the coal seam and overlying strata, and considering a certain safety reserve coefficient, it is assumed that the rock mass is a rigid retaining wall, and its height is equal to the burial depth of the coal seam floor. In addition, during the theoretical analysis process, the influence of the waste dump bench is temporarily ignored.

[0024] Figure 2 FIG. is a schematic diagram of a two-dimensional section of a composite slope of a waste dump provided by an embodiment of the present invention. Figure 2 In the figure, the covered mining slope can be regarded as a rigid retaining wall with an inclined wall back due to its large stiffness, while the waste dump slope can be regarded as the soil mass behind the wall. To ensure the stability of the waste dump slope, its waste dumping height is often strictly restricted, so the filling surface is in a broken line shape.

[0025] Among them, the geometric parameters of the two-dimensional section of the composite slope of the waste dump include: the angle α between the soil-rock contact surface and the vertical line, the slope angle β of the waste dump slope (that is, the inclination angle between the filling surface and the horizontal plane), and the retaining wall height H (that is, the burial depth of the coal seam floor); the physical and mechanical parameters of the discharged soil mass include: the unit weight γ of the soil, the internal friction angle of the soil, the friction angle of the soil-rock contact surface, and the cohesion c of the soil. The soil-rock contact surface represents the contact surface between the discharged soil mass and the rock mass. The friction angle of the soil-rock contact surface, that is, the friction angle between the wall back of the retaining wall and the discharged soil mass, and its value is generally determined by experiments. When there is no experimental data, it is generally taken as (1 / 3 - 2 / 3).

[0026] Step S104: Calculate the earth pressure on the soil-rock contact surface based on the Coulomb earth pressure theory, geometric parameters, and physical and mechanical parameters.

[0027] It is known that the change in the angle between the internal sliding surface of the discharged soil mass and the horizontal plane determines the shape of the filling surface of the sliding soil mass. When , the filling surface is a plane; when , the filling surface is in a broken line shape. Among them, represents the critical value of the angle between the internal sliding surface of the soil mass and the horizontal plane, denoted as the preset angle critical value. And, the calculation methods of the earth pressure on the soil-rock contact surface for different-shaped filling surfaces are different. Therefore, the embodiments of the present invention first need to determine whether the filling surface of the sliding soil mass is a plane-type filling surface or a broken line-type filling surface based on the above geometric parameters and physical and mechanical parameters, and then calculate the earth pressure on the soil-rock contact surface according to the Coulomb earth pressure theory based on the actual shape of the filling surface of the sliding soil mass.

[0028] Step S106: Calculate the required soil stacking volume when the extension dimension of the toe counterweight platform in the three-dimensional space is 1 m, based on the soil pressure at the soil-rock contact surface, the friction angle at the soil-rock contact surface, the angle between the soil-rock contact surface and the vertical line, and the unit weight of the soil.

[0029] Among them, the toe counterweight platform is used to weaken the shearing effect of the composite slope of the waste dump on the toe area.

[0030] When setting the toe counterweight platform, reasonable control of the soil stacking volume is crucial. Excessive soil stacking volume may cause slope failure along the soil-rock contact surface and increase the project cost; while too small soil stacking volume cannot effectively weaken the slope shearing effect and is difficult to inhibit the spread of coal fires. Therefore, in the embodiments of the present invention, after calculating the soil pressure at the soil-rock contact surface, on the premise of the force balance at the soil-rock contact surface, according to the soil pressure at the soil-rock contact surface, the friction angle at the soil-rock contact surface, the angle between the soil-rock contact surface and the vertical line, and the unit weight of the soil, calculate the required soil stacking volume when the extension dimension of the toe counterweight platform in the three-dimensional space is 1 m under the condition of preventing and controlling coal fire areas, so as to provide a theoretical basis for the reasonable design of the toe counterweight platform.

[0031] In the embodiments of the present invention, when calculating the volume of any space, the default extension dimension of the three-dimensional space is 1 m. Based on this, the volume of each space is numerically equal to the area of its corresponding two-dimensional section, which is convenient for the calculation of various parameters.

[0032] Step S108: Take the geometric shape condition that the two-dimensional section is a parallelogram and the platform slope angle is the slope angle of the waste dump slope, and calculate the geometric parameters of the toe counterweight platform based on the soil stacking volume, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line.

[0033] Specifically, Figure 3 is a schematic diagram of the common geometric shapes of the soil mass piled at the toe, as Figure 3 shown. The geometric shapes include: triangle, trapezoid, parallelogram. In theoretical analysis, the sliding soil mass and rock mass are idealized as rigid bodies. However, in actual engineering, these materials exhibit elastoplastic characteristics. The shearing effect of the waste dump slope gradually attenuates as it moves away from the toe. Therefore, the piled soil mass should be as close to the toe as possible to maximize the inhibition of the upward displacement of the rock stratum. From a mechanical perspective, the centroid of the trapezoidal piled body is far from the toe, which will exert a large additional bending moment on the layered rock mass near the toe, is not conducive to controlling the rock stratum displacement, and results in a higher soil stacking requirement and a larger occupied area, which does not conform to the design principle of land saving and loss reduction in open-pit mines. In addition, under the condition of the same soil stacking volume, the triangular piled body has a large occupied area, which may affect the space utilization efficiency. In summary, the parallelogram piled body performs better in terms of soil stacking volume, displacement control effect, and land occupation optimization, and is a more reasonable choice. Therefore, in the embodiments of the present invention, the shape of the toe counterweight platform is designed as a parallelogram, and the platform slope angle is taken as the slope angle of the waste dump slope.

[0034] After calculating the earth stacking volume required when the extension dimension of the toe counter-pressure platform in the three-dimensional space is 1 m, the value of the earth stacking volume can be used as the area of the toe counter-pressure platform in the two-dimensional section. Next, according to the slope angle of the waste dump slope and the angle between the soil-rock contact surface and the vertical line, the relationship between the width and height of the toe counter-pressure platform can be constructed. Then, by combining that the product of the width and height is equal to the area, the width and height of the toe counter-pressure platform can be calculated, that is, the geometric parameters of the toe counter-pressure platform.

[0035] Regarding the problem of treating the induced coal fire area in the waste dump, the embodiment of the present invention proposes to set a counter-pressure platform at the toe as a treatment measure. First, based on the Coulomb earth pressure theory, the geometric parameters of the two-dimensional section of the composite slope of the waste dump, and the physical and mechanical parameters of the discharged soil mass, the earth pressure on the soil-rock contact surface is calculated. Then, aiming at weakening the shear action of the composite slope of the waste dump on the toe area, the earth stacking volume required when the extension dimension of the counter-pressure platform set at the toe of the composite slope of the waste dump in the three-dimensional space is 1 m is calculated. Finally, with the two-dimensional section being a parallelogram and the platform slope angle being the slope angle of the waste dump slope as the geometric shape condition of the toe counter-pressure platform, the geometric parameters of the toe counter-pressure platform are calculated according to the earth stacking volume, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line. The method of setting a counter-pressure platform at the toe of the waste dump slope in the present invention, on the one hand, can improve the slope stability; on the other hand, it can weaken the shear action of the waste dump slope on the toe, inhibit the displacement of the toe soil body and rock stratum, reduce the crack development, and lower the air permeability, so as to effectively contain the coal seam combustion and spread. Compared with other coal fire treatment measures, this method has a lower cost, and the construction process is simple and feasible, with a wide application prospect. In addition, before the formation of the coal fire area, a counter-pressure platform can be constructed in advance as a preventive measure, so as to effectively reduce the occurrence risk of the coal fire area.

[0036] In an optional embodiment, in step S104, based on the Coulomb earth pressure theory, geometric parameters, and physical and mechanical parameters, calculating the earth pressure on the soil-rock contact surface specifically includes the following steps: Step S1041, using the equivalent internal friction angle method to process the soil unit weight, the internal friction angle of the soil mass, the cohesion of the soil mass, and the retaining wall height to obtain the equivalent internal friction angle of the soil mass.

[0037] Step S1042, based on the angle between the soil-rock contact surface and the vertical line, the friction angle of the soil-rock contact surface, the equivalent internal friction angle of the soil mass, and the slope angle of the waste dump slope, calculate the angle between the internal sliding surface of the discharged soil mass and the horizontal plane.

[0038] Step S1043, based on the preset angle critical value and the angle between the internal sliding surface of the discharged soil mass and the horizontal plane, use the Coulomb earth pressure theory to calculate the earth pressure on the soil-rock contact surface.

[0039] Since the discharged soil mass is derived from the loose mixture of soil and rock stripped during open-pit mining, although its natural cohesion is small, it has undergone a certain degree of compaction during the soil discharging process and still has non-negligible cohesion. In the embodiments of the present invention, the active earth pressure at the soil-rock contact surface (referred to as the soil-rock contact surface earth pressure for short) needs to be calculated according to the Coulomb earth pressure theory. Since the traditional Coulomb earth pressure coefficient can only calculate the case where the cohesion c of the soil mass is 0 and the filling surface is a plane. For the working conditions where the filling surface is irregular and the cohesion c of the soil mass is >0, there is no direct Coulomb earth pressure calculation formula. Therefore, in the embodiments of the present invention, it is necessary to first perform an equivalent treatment on the cohesion by using the equivalent internal friction angle method, and then use the Coulomb earth pressure theory.

[0040] Specifically, the user needs to adopt the corresponding equivalent internal friction angle formula according to the actual working conditions. For example, for the soil-rock mixture with a retaining wall height greater than 30 meters and small cohesion, the equivalent internal friction angle formula proposed by Meyerhof can be adopted: . Wherein, represents the internal friction angle of the soil mass, represents the cohesion of the soil mass, represents the unit weight of the soil mass, represents the height of the retaining wall, represents the equivalent internal friction angle of the soil mass.

[0041] Next, assuming that the slope surface of the waste dump is a plane, during the derivation of the traditional Coulomb active earth pressure coefficient, the calculation formula of the included angle between the internal sliding surface of the soil mass and the horizontal plane is used to calculate the value of the included angle : . Obviously, when the included angle between the soil-rock contact surface and the vertical line, the friction angle of the soil-rock contact surface, the equivalent internal friction angle of the soil mass, and the slope angle of the waste dump slope are known, substituting into the above formula can solve the included angle between the internal sliding surface of the discharged soil mass and the horizontal plane.

[0042] After calculating the included angle between the internal sliding surface of the discharged soil mass and the horizontal plane, as can be seen from the above description, it is necessary to first determine whether the filling surface of the sliding soil mass is a plane filling surface or a broken-line filling surface according to the comparison result of its size with the preset included angle critical value, and then calculate the soil-rock contact surface earth pressure according to the actual shape of the filling surface of the sliding soil mass based on the Coulomb earth pressure theory.

[0043] In an alternative embodiment, in step S1043 above, based on a preset critical angle value and the angle between the internal sliding surface of the discharged soil mass and the horizontal plane, the earth pressure at the soil-rock contact surface is calculated using the Coulomb earth pressure theory, which specifically includes the following steps: Step S1043a, when the angle between the internal sliding surface of the discharged soil mass and the horizontal plane is greater than or equal to the preset critical angle value, determine that the filling surface of the sliding soil mass is a planar filling surface.

[0044] Step S1043b, based on the equivalent internal friction angle of the soil mass, the angle between the soil-rock contact surface and the vertical line, the friction angle of the soil-rock contact surface, and the slope angle of the waste dump, calculate the active earth pressure coefficient when the filling surface of the sliding soil mass is a planar filling surface.

[0045] Step S1043c, based on the active earth pressure coefficient, the unit weight of the soil mass, and the height of the retaining wall, calculate the first active earth pressure.

[0046] Step S1043d, take the first active earth pressure as the earth pressure at the soil-rock contact surface.

[0047] Specifically, when the filling surface of the sliding soil mass is a planar filling surface, the embodiments of the present invention directly use formula 1: to calculate the active earth pressure coefficient , and use formula 2: to calculate the Coulomb active earth pressure of cohesive soil, denoted as the first active earth pressure . When the filling surface of the sliding soil mass is a planar filling surface, the earth pressure at the soil-rock contact surface .

[0048] In an alternative embodiment, in step S1043 above, based on a preset critical angle value and the angle between the internal sliding surface of the discharged soil mass and the horizontal plane, the earth pressure at the soil-rock contact surface is calculated using the Coulomb earth pressure theory, and further includes the following steps: Step S10431, when the angle between the internal sliding surface of the discharged soil mass and the horizontal plane is less than the preset critical angle value, determine that the filling surface of the sliding soil mass is a broken-line filling surface.

[0049] Step S10432, convert the broken-line filling surface into a planar filling surface to calculate the equivalent retaining wall height of the corresponding triangular equivalent sliding soil mass.

[0050] Step S10433, based on the height of the retaining wall and the equivalent retaining wall height, determine the retaining wall height equivalent coefficient.

[0051] Step S10434, based on the retaining wall height equivalent coefficient and the first active earth pressure, calculate the second active earth pressure when the filling surface of the sliding soil mass is a broken-line filling surface.

[0052] Step S10435, take the second active earth pressure as the earth pressure at the soil-rock contact surface.

[0053] Specifically, when the filling surface of the sliding soil mass is a broken-line filling surface, the above formula 2 cannot be directly used to calculate the active earth pressure. It is necessary to first equivalently process the broken-line filling surface into a flat filling surface. Refer to Figure 4 , that is, the above equivalent processing is to equivalently process the quadrilateral sliding soil mass COBD into a triangular sliding soil mass A’OB’. After the equivalent processing, according to the condition that the areas before and after equivalence are equal, the equivalent retaining wall height of the triangular equivalent sliding soil mass can be calculated. , and then use the following formula to calculate the retaining wall height equivalent coefficient: .

[0054] Replace the retaining wall height in the above formula 2 with the equivalent retaining wall height, and formula 3 can be obtained: , that is to say, after calculating the retaining wall height equivalent coefficient, according to the product of the square of the calculated retaining wall height equivalent coefficient and the first active earth pressure, the Coulomb active earth pressure of cohesive soil when the filling surface of the sliding soil mass is a broken-line filling surface can be obtained, which is recorded as the second active earth pressure. . In the case where the filling surface of the sliding soil mass is a broken-line filling surface, the earth pressure at the soil-rock contact surface .

[0055] In an optional implementation manner, in the above step S10432, converting the broken-line filling surface into a flat filling surface to calculate the equivalent retaining wall height of the corresponding triangular equivalent sliding soil mass specifically includes the following steps: Step S104321, based on the angle between the internal sliding surface of the discharged soil mass and the horizontal plane, determine the quadrilateral actual sliding soil mass in the discharged soil mass.

[0056] Step S104322, convert the quadrilateral actual sliding soil mass into a triangular equivalent sliding soil mass with a flat filling surface.

[0057] Step S104323, with the condition that the area of the actual sliding soil mass is equal to the area of the triangular equivalent sliding soil mass, calculate the equivalent retaining wall height of the triangular equivalent sliding soil mass.

[0058] Specifically, refer to Figure 4 , after determining the angle between the internal sliding surface of the discharged soil mass and the horizontal plane, the position of point C in Figure 4 can be determined, and then the quadrilateral actual sliding soil mass in the discharged soil mass: COBD can be determined. Convert it to a flat filling surface, and then the triangular equivalent sliding soil mass A’OB’ can be obtained.

[0059] In the embodiments of the present invention, on the condition that the area of the actual sliding soil mass in a quadrilateral shape is equal to the area of the triangular equivalent sliding soil mass, the equivalent retaining wall height of the triangular equivalent sliding soil mass is calculated. Therefore, it is necessary to determine the expressions for the area of the actual sliding soil mass and the area of the triangular equivalent sliding soil mass respectively.

[0060] Among them, the area of the actual sliding soil mass COBD is the difference between the area of triangle AOB and the area of triangle ACD, which is expressed as: , so, in the next step, it is necessary to calculate the area of triangle AOB and the area of triangle ACD .

[0061] Through Figure 4 it can be known that , represents the length of section CD, represents the height of triangle ACD. According to the sine theorem, it can be calculated that: , among which, represents the length of section DO, and then can be calculated. The in the above formula can also be calculated according to the sine theorem: . Substituting it into the formula of gives: .

[0062] Through Figure 4 it can be known that , among which, represents the length of section AB, represents the height of triangle AOB. According to the sine theorem, it can be calculated that: , . Substituting the two into the formula of gives: .

[0063] Thus, it can be obtained that .

[0064] It is known that A'B' is parallel to AB. Therefore, the calculation method of the area of triangle A'OB' is the same as that of triangle AOB, and only H in the area formula of triangle AOB needs to be changed to . That is, the area of triangle A'OB' .

[0065] Next, according to the condition that the areas before and after equivalence are equal: , the equivalent retaining wall height of the triangular equivalent sliding soil mass can be calculated: , that is, the retaining wall height equivalence coefficient: 。

[0066] In an alternative embodiment, in step S106 above, based on the earth-rock contact surface earth pressure, the earth-rock contact surface friction angle, the angle between the earth-rock contact surface and the vertical line, and the unit weight of the soil, the amount of soil stacking required for the slope toe counterweight platform to extend 1 meter in three-dimensional space is calculated, which specifically includes the following steps: Step S1061: Based on the earth-rock contact surface earth pressure and the earth-rock contact surface friction angle, calculate the frictional force applied to the rock mass block when the composite slope of the waste dump has a tendency to slide in a circular arc.

[0067] Step S1062: Taking the force balance of the earth-rock contact surface as the condition, based on the frictional force, the angle between the earth-rock contact surface and the vertical line, and the unit weight of the soil, calculate the amount of soil stacking required for the slope toe counterweight platform to extend 1 meter in three-dimensional space.

[0068] Specifically, referring to Figure 5 , the composite slope of the waste dump exerts a normal force and a frictional force on the rock mass block on the earth-rock interface. When the composite slope of the waste dump has a tendency to slide in a circular arc, the sliding soil mass has an upward movement tendency relative to the mining slope. During this process, the sliding soil mass exerts an upward frictional force on the rock mass of the mining slope through the earth-rock contact surface, thereby inducing a shear effect in the slope toe area and causing the rock mass to displace upward. In actual engineering, this shear effect may cause deformation and damage to the overlying strata of the coal seam. To reduce the upward displacement of the slope toe and the influence of the shear action on the overlying strata of the coal seam, in the embodiment of the present invention, a counterweight platform is arranged at the slope toe. The amount of soil stacking of the counterweight platform is calculated based on the frictional force exerted by the composite slope of the waste dump on the rock mass block. To simplify the calculation and ensure a safety reserve, it is assumed that there is a relative movement tendency on the earth-rock contact surface above the coal seam floor, and the frictional force is calculated based on the sliding frictional force in the limit state. According to the decomposition of the earth-rock contact surface earth pressure in the direction of the force shown in Figure 4 , the normal force exerted on the rock mass block when the composite slope of the waste dump has a tendency to slide in a circular arc, and the frictional force exerted on the rock mass block when the composite slope of the waste dump has a tendency to slide in a circular arc.

[0069] To make the earth-rock contact surface in force balance, the component force of the gravity of the slope toe counterweight platform in the direction opposite to the frictional force should be equal to , that is, , G represents the gravity of the slope toe counterweight platform, , represents the amount of soil stacking (i.e., volume) required for the slope toe counterweight platform to extend 1 meter in three-dimensional space. From this, it can be obtained that The arithmetic expression can be transformed as follows: the volume of the piled soil That is to say, after calculating the frictional force, based on the frictional force, the angle between the soil-rock contact surface and the vertical line, and the unit weight of the soil, the volume of the piled soil required for the counter-pressure platform at the toe of the slope to extend 1 meter in the three-dimensional space can be further calculated.

[0070] In an alternative embodiment, in the above step S108, based on the volume of the piled soil, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line, calculate the geometric parameters of the counter-pressure platform at the toe of the slope, which specifically includes the following steps: Step S1081, based on the volume of the piled soil, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line, calculate the height of the counter-pressure platform at the toe of the slope.

[0071] Step S1082, based on the volume of the piled soil and the height of the counter-pressure platform at the toe of the slope, calculate the width of the counter-pressure platform at the toe of the slope.

[0072] According to Figure 5 it can be known that if the height of the counter-pressure platform at the toe of the slope is and the width is , then there is: Moreover, through the description in the above text, it can be known that the value of the volume of the piled soil is equal to the area of the counter-pressure platform at the toe of the slope in the two-dimensional section, that is, V = bh. From this, the height of the counter-pressure platform at the toe of the slope can be obtained as: , and the width of the counter-pressure platform at the toe of the slope is .

[0073] In summary, for the method of setting a counter-pressure platform at the toe of the composite slope of the waste dump proposed in the embodiment of the present invention, on the one hand, it can improve the slope stability; on the other hand, it can weaken the shearing action of the waste dump slope on the toe of the slope, inhibit the displacement of the soil and rock layers at the toe of the slope, reduce the development of fissures, and lower the air permeability, thereby effectively curbing the further combustion of the coal seam. Compared with other coal fire control measures, this method has a lower cost, convenient access to materials, can directly use the waste soil piled up in the waste dump as the toe-pressing material, the construction process is simple and feasible, and has a wide application prospect. In addition, before the formation of the coal fire area, a counter-pressure platform can be constructed in advance as a preventive measure to effectively reduce the occurrence risk of the coal fire area.

[0074] In order to verify the performance of the method provided in the embodiment of the present invention, referring to the embodiment of the present invention, a certain mine waste dump-induced coal fire area is treated, the geometric parameters of the counter-pressure platform at the toe of the slope are designed, and FLAC3D is used for simulation analysis to compare the displacement and stress distribution characteristics before and after toe-pressing, and the displacement change of the overlying rock layer of the coal seam is monitored mainly to verify the inhibitory effect of the slope toe-pressing measure on the formation of the coal fire area, and further evaluate the rationality of the calculation formula of the toe-piled soil volume. Combining historical exploration data and on-site measurement data, the height and width of the counter-pressure platform are calculated.

[0075] To prevent and control the formation and spread of the coal fire area in this open-pit mine, it is calculated that an anti-pressure platform needs to be set up in the unburned area of the coal seam at the foot of the waste dump slope. The height of the platform is 17.72 m, and the width of the platform is 74.52 m of soil mass. To verify the rationality and effectiveness of the calculation formula for the amount of pressure on the foot proposed in this study, a slope model of the waste dump of this open-pit mine was established using FLAC3D to analyze the displacement of the overlying strata of the coal seam at the foot of the slope before and after stacking soil at the foot of the slope. Three monitoring profiles (M1, M2, M3) were arranged above the coal seam in the potential coal fire area to quantify the displacement characteristics of the strata at different positions. The positions of the model and the monitoring lines are as Figure 6 shown. When conducting numerical analysis, the rock mechanics parameters of each stratum are shown in Table 1 below.

[0076] Table 1 Rock mechanics parameters of each stratum

[0077] Figure 7 Figure 12 is the displacement distribution characteristic diagram of each monitoring line before the anti-pressure platform at the foot of the slope is set up. The results show that the strata within the potential coal fire area as a whole show an upward displacement trend, and the displacement amount gradually decreases with the increase of depth and turns negative after a certain depth, that is, a downward displacement occurs. The displacement amount of the surface loose layer is the largest, mainly because its mechanical strength is low and the plastic deformation is significant. The upward displacement of the M3 monitoring line far from the foot of the slope within the surface loose layer range is slightly larger than that of the M1 monitoring line close to the foot of the slope, but at a depth of 15 - 30 m (within the hard rock stratum), the displacement amount of the M3 monitoring profile is smaller than that of the M1 monitoring profile. This shows that in the relatively hard rock stratum, the shear effect of the waste dump slope gradually attenuates from the foot of the slope to the distance. In addition, because the rock slope is assumed to be a rigid body in the theoretical analysis, while the actual slope has elastoplastic properties, there is a certain difference between the simulation results of the surface loose layer and the theoretical analysis.

[0078] Figure 8It is the displacement distribution characteristic diagram of the monitoring line after the toe counterweight platform is set. The results show that the displacement values of the monitoring line M1 within the depth range of 0–30 m are basically close to 0, indicating that in the rock layer area near the soil-rock contact surface, the self-weight of the surface accumulated soil effectively weakens the shearing effect of the waste dump slope on the original mining slope. This further verifies the rationality of the calculation formula for the soil volume at the toe derived in the embodiment of the present invention. There is still a certain displacement of the monitoring line M2 in the shallow rock layer, but it is significantly lower than that before the soil is piled. This is mainly because the shallow rock layer is composed of soft and loose layers, and large plastic deformations occur under the influence of the load of the accumulated soil. In addition, M3 is located at the toe of the piled slope, and the accumulated soil itself exerts a certain shearing effect on the loose layer, resulting in an increase in the displacement of the shallow rock layer. However, this influence is limited to the shallow loose layer, and the displacement rapidly decreases with the increase in depth. Within the depth range of 15–30 m, the displacement value of the rock layer is significantly lower than that before the soil is piled. At this time, the overlying rock layer of the coal seam remains intact, the crack development is controlled, blocking the oxygen channel between the coal seam and the surface, thus effectively curbing the formation and spread of the coal fire area.

[0079] Embodiment 2 The embodiment of the present invention also provides an anti-pressure platform determination device for preventing and controlling coal fire areas in open-pit mines. This device is mainly used to execute the anti-pressure platform determination method for preventing and controlling coal fire areas in open-pit mines provided in the above Embodiment 1. The following specifically introduces the anti-pressure platform determination device for preventing and controlling coal fire areas in open-pit mines provided by the embodiment of the present invention.

[0080] Figure 9 It is the functional module diagram of an anti-pressure platform determination device for preventing and controlling coal fire areas in open-pit mines provided by the embodiment of the present invention. As Figure 9 shown, this device mainly includes: an acquisition module 10, a first calculation module 20, a second calculation module 30, and a third calculation module 40, where: The acquisition module 10 is used to acquire the geometric parameters of the two-dimensional profile of the waste dump composite slope and the physical and mechanical parameters of the dumped soil; among them, the geometric parameters include: the angle between the soil-rock contact surface and the vertical line, the slope angle of the waste dump slope, and the retaining wall height; the physical and mechanical parameters include: soil unit weight, soil internal friction angle, soil-rock contact surface friction angle, and soil cohesion.

[0081] The first calculation module 20 is used to calculate the soil pressure on the soil-rock contact surface based on the Coulomb earth pressure theory, geometric parameters, and physical and mechanical parameters.

[0082] The second calculation module 30 is used to calculate the soil volume required when the three-dimensional space extension dimension of the toe counterweight platform is 1 m based on the soil pressure on the soil-rock contact surface, the soil-rock contact surface friction angle, the angle between the soil-rock contact surface and the vertical line, and the soil unit weight; among them, the toe counterweight platform is used to weaken the shearing effect of the waste dump composite slope on the toe area.

[0083] The third calculation module 40 is configured to use the geometric shape condition that the two-dimensional profile is a parallelogram and the platform slope angle is the slope angle of the waste dump slope as the toe counterweight platform, and calculate the geometric parameters of the toe counterweight platform based on the soil stacking volume, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line.

[0084] Regarding the treatment problem of the induced coal fire area in the waste dump, the embodiment of the present invention proposes to set a counterweight platform at the toe as a treatment measure. First, according to the Coulomb earth pressure theory, the geometric parameters of the two-dimensional profile of the composite slope of the waste dump, and the physical and mechanical parameters of the discharged soil mass, calculate the earth pressure on the soil-rock contact surface. Then, aiming at weakening the shear effect of the composite slope of the waste dump on the toe area, calculate the required soil stacking volume when the extension dimension of the counterweight platform set at the toe of the composite slope of the waste dump in the three-dimensional space is 1 meter. Finally, use the geometric shape condition that the two-dimensional profile is a parallelogram and the platform slope angle is the slope angle of the waste dump slope as the toe counterweight platform, and calculate the geometric parameters of the toe counterweight platform according to the soil stacking volume, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line. By setting a counterweight platform at the toe of the waste dump slope in the embodiment of the present invention, on the one hand, the slope stability can be improved; on the other hand, the shear effect of the waste dump slope on the toe can be weakened, the displacement of the toe soil mass and rock stratum can be inhibited, so as to reduce the fissure development and the air permeability, thereby effectively curbing the coal seam combustion and spread. Compared with other coal fire treatment measures, the implementation cost of the embodiment of the present invention is relatively low, and the construction process is simple and feasible, with broad application prospects. In addition, before the formation of the coal fire area, a counterweight platform can be constructed in advance as a preventive measure, thereby effectively reducing the occurrence risk of the coal fire area.

[0085] Optionally, the first calculation module 20 includes: A processing unit, configured to process the soil unit weight, the soil internal friction angle, the soil cohesion, and the retaining wall height by using the equivalent internal friction angle method to obtain the equivalent internal friction angle of the soil mass.

[0086] A first calculation unit, configured to calculate the angle between the internal sliding surface of the discharged soil mass and the horizontal plane based on the angle between the soil-rock contact surface and the vertical line, the friction angle of the soil-rock contact surface, the equivalent internal friction angle of the soil mass, and the slope angle of the waste dump slope.

[0087] A second calculation unit, configured to calculate the earth pressure on the soil-rock contact surface by using the Coulomb earth pressure theory based on a preset angle critical value and the angle between the internal sliding surface of the discharged soil mass and the horizontal plane.

[0088] Optionally, the second calculation unit includes: A first determination subunit, configured to determine that the filling surface of the sliding soil mass is a planar filling surface when the angle between the internal sliding surface of the discharged soil mass and the horizontal plane is greater than or equal to the preset angle critical value.

[0089] The first calculation subunit is configured to calculate the active earth pressure coefficient when the filling surface of the sliding soil mass is a planar filling surface based on the equivalent internal friction angle of the soil mass, the angle between the soil-rock contact surface and the vertical line, the friction angle of the soil-rock contact surface, and the slope angle of the waste dump slope.

[0090] The second calculation subunit is configured to calculate the first active earth pressure based on the active earth pressure coefficient, the unit weight of the soil mass, and the height of the retaining wall. The second determination subunit is configured to use the first active earth pressure as the earth pressure on the soil-rock contact surface.

[0091] Optionally, the second calculation unit further includes: The third determination subunit is configured to determine that the filling surface of the sliding soil mass is a broken-line filling surface when the angle between the internal sliding surface of the discharged soil mass and the horizontal plane is less than the preset critical angle value.

[0092] The conversion and calculation subunit is configured to convert the broken-line filling surface into a planar filling surface to calculate the equivalent retaining wall height of the corresponding triangular equivalent sliding soil mass.

[0093] The fourth determination subunit is configured to determine the retaining wall height equivalent coefficient based on the height of the retaining wall and the equivalent retaining wall height.

[0094] The third calculation subunit is configured to calculate the second active earth pressure when the filling surface of the sliding soil mass is a broken-line filling surface based on the retaining wall height equivalent coefficient and the first active earth pressure.

[0095] The fifth determination subunit is configured to use the second active earth pressure as the earth pressure on the soil-rock contact surface.

[0096] Optionally, the conversion and calculation subunit is specifically configured to: Determine the quadrilateral actual sliding soil mass in the discharged soil mass based on the angle between the internal sliding surface of the discharged soil mass and the horizontal plane.

[0097] Convert the quadrilateral actual sliding soil mass into a triangular equivalent sliding soil mass with a planar filling surface.

[0098] Calculate the equivalent retaining wall height of the triangular equivalent sliding soil mass on the condition that the area of the actual sliding soil mass is equal to the area of the triangular equivalent sliding soil mass.

[0099] Optionally, the second calculation module 30 is specifically configured to: Calculate the frictional force applied to the rock mass block when the waste dump composite slope has a circular arc sliding tendency based on the earth pressure on the soil-rock contact surface and the friction angle of the soil-rock contact surface.

[0100] Taking the force balance of the soil-rock contact surface as the condition, based on the frictional force, the angle between the soil-rock contact surface and the vertical line, and the unit weight of the soil, calculate the amount of soil stacking required when the extension dimension of the toe counterweight platform in the three-dimensional space is 1 meter.

[0101] Optionally, the third calculation module 40 is specifically configured to: Based on the amount of soil stacking, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line, calculate the height of the toe counterweight platform.

[0102] Based on the amount of soil stacking and the height of the toe counterweight platform, calculate the width of the toe counterweight platform.

[0103] Embodiment III Refer to Figure 10 , this embodiment of the present invention provides an electronic device, which includes: a processor 60, a memory 61, a bus 62, and a communication interface 63. The processor 60, the communication interface 63, and the memory 61 are connected through the bus 62. The processor 60 is configured to execute an executable module stored in the memory 61, such as a computer program.

[0104] Among them, the memory 61 may include a high-speed random access memory (RAM, Random Access Memory), and may also include a non-volatile memory, such as at least one disk memory. Through at least one communication interface 63 (which can be wired or wireless), a communication connection between this system network element and at least one other network element is realized, and the Internet, wide area network, local area network, metropolitan area network, etc. can be used.

[0105] The bus 62 may be an ISA bus, a PCI bus, an EISA bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of simplicity of representation, Figure 10 only a bidirectional arrow is used in

[0106] Among them, the memory 61 is used to store a program. After receiving an execution instruction, the processor 60 executes the program. The method executed by the device defined by the process disclosed in any one of the foregoing embodiments of the present invention can be applied to the processor 60 or implemented by the processor 60.

[0107] The processor 60 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in the processor 60 or instructions in the form of software. The above-mentioned processor 60 may be a general-purpose processor, including a central processing unit (CPU for short), a network processor (NP for short), etc.; it may also be a digital signal processor (DSP for short), an application specific integrated circuit (ASIC for short), a field-programmable gate array (FPGA for short), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of the present invention can be directly embodied as being executed by a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory 61, and the processor 60 reads the information in the memory 61 and combines its hardware to complete the steps of the above method.

[0108] A computer program product of a method and device for determining a backpressure platform for preventing and controlling coal fire areas in open-pit mines provided by an embodiment of the present invention includes a computer-readable storage medium storing non-volatile program code executable by a processor. The instructions included in the program code can be used to execute the method described in the foregoing method embodiments. For specific implementation, reference can be made to the method embodiments and will not be elaborated here.

[0109] In addition, in each embodiment of the present invention, each functional unit may be integrated in one processing unit, or each unit may exist physically alone, or two or more units may be integrated in one unit.

[0110] When the above-mentioned functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium executable by a processor. Based on such understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes.

[0111] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0112] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0113] In addition, the terms "horizontal", "vertical", "hanging", etc. do not mean that the components are required to be absolutely horizontal or hanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0114] In the description of the present invention, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "install", "connect", "couple" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for determining a backpressure platform for preventing and controlling coal fires in open-pit coal mines, characterized in that, Including: Obtaining the geometric parameters of the two-dimensional profile of the composite slope of the waste dump and the physical and mechanical parameters of the dumped soil mass; wherein, the geometric parameters include: the angle between the soil-rock contact surface and the vertical line, the slope angle of the waste dump slope, and the height of the retaining wall; the physical and mechanical parameters include: the unit weight of the soil, the internal friction angle of the soil, the friction angle of the soil-rock contact surface, and the cohesion of the soil mass; Calculating the soil pressure on the soil-rock contact surface based on the Coulomb earth pressure theory, the geometric parameters, and the physical and mechanical parameters; Calculating the required soil stacking volume when the extension dimension of the slope toe counter-pressure platform in the three-dimensional space is 1 meter based on the soil pressure on the soil-rock contact surface, the friction angle of the soil-rock contact surface, the angle between the soil-rock contact surface and the vertical line, and the unit weight of the soil; wherein, the slope toe counter-pressure platform is used to weaken the shearing effect of the composite slope of the waste dump on the slope toe area; Taking the two-dimensional profile as a parallelogram and the platform slope angle as the slope angle of the waste dump slope as the geometric shape condition of the slope toe counter-pressure platform, and calculating the geometric parameters of the slope toe counter-pressure platform based on the soil stacking volume, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line.

2. The method for determining the backpressure platform for preventing and controlling coal fire areas in open-pit mines according to claim 1, wherein Calculating the soil pressure on the soil-rock contact surface based on the Coulomb earth pressure theory, the geometric parameters, and the physical and mechanical parameters, including: Processing the unit weight of the soil, the internal friction angle of the soil, the cohesion of the soil mass, and the height of the retaining wall by using the equivalent internal friction angle method to obtain the equivalent internal friction angle of the soil mass; Calculating the angle between the internal sliding surface of the dumped soil mass and the horizontal plane based on the angle between the soil-rock contact surface and the vertical line, the friction angle of the soil-rock contact surface, the equivalent internal friction angle of the soil mass, and the slope angle of the waste dump slope; Calculating the soil pressure on the soil-rock contact surface by using the Coulomb earth pressure theory based on a preset angle critical value and the angle between the internal sliding surface of the dumped soil mass and the horizontal plane.

3. The method for determining the backpressure platform for preventing and controlling coal fire areas in open-pit mines according to claim 2, wherein Calculating the soil pressure on the soil-rock contact surface by using the Coulomb earth pressure theory based on a preset angle critical value and the angle between the internal sliding surface of the dumped soil mass and the horizontal plane, including: When the angle between the internal sliding surface of the dumped soil mass and the horizontal plane is greater than or equal to the preset angle critical value, determining that the filling surface of the sliding soil mass is a planar filling surface; Calculating the active earth pressure coefficient when the filling surface of the sliding soil mass is a planar filling surface based on the equivalent internal friction angle of the soil mass, the angle between the soil-rock contact surface and the vertical line, the friction angle of the soil-rock contact surface, and the slope angle of the waste dump slope; Calculating the first active earth pressure based on the active earth pressure coefficient, the unit weight of the soil, and the height of the retaining wall; Taking the first active earth pressure as the soil pressure on the soil-rock contact surface.

4. The method for determining the backpressure platform for preventing and controlling coal fire areas in open-pit mines according to claim 3, wherein Calculating the soil pressure on the soil-rock contact surface by using the Coulomb earth pressure theory based on a preset angle critical value and the angle between the internal sliding surface of the dumped soil mass and the horizontal plane, further including: When the angle between the internal sliding surface of the dumped soil mass and the horizontal plane is less than the preset angle critical value, determining that the filling surface of the sliding soil mass is a stepped filling surface; Converting the stepped filling surface into a planar filling surface to calculate the equivalent retaining wall height of the corresponding triangular equivalent sliding soil mass; Determining the retaining wall height equivalent coefficient based on the height of the retaining wall and the equivalent retaining wall height; Calculate the second active earth pressure when the filling surface of the sliding soil mass is a broken-line filling surface based on the retaining wall height equivalent coefficient and the first active earth pressure; Take the second active earth pressure as the earth pressure on the soil-rock contact surface.

5. The method for determining the backpressure platform for preventing and controlling coal fire areas in open-pit mines according to claim 4, wherein Convert the broken-line filling surface into a flat filling surface to calculate the equivalent retaining wall height of the corresponding triangular equivalent sliding soil mass, including: Based on the angle between the internal sliding surface of the waste soil mass and the horizontal plane, determine the quadrilateral actual sliding soil mass in the waste soil mass; Convert the quadrilateral actual sliding soil mass into a triangular equivalent sliding soil mass with a flat filling surface; Calculate the equivalent retaining wall height of the triangular equivalent sliding soil mass on the condition that the area of the actual sliding soil mass is equal to the area of the triangular equivalent sliding soil mass.

6. The method for determining the backpressure platform for preventing and controlling coal fire areas in open-pit mines according to claim 1, wherein Based on the earth pressure on the soil-rock contact surface, the friction angle of the soil-rock contact surface, the angle between the soil-rock contact surface and the vertical line, and the soil unit weight, calculate the amount of soil stacking required when the three-dimensional extension dimension of the toe counterweight platform is 1 m, including: Based on the earth pressure on the soil-rock contact surface and the friction angle of the soil-rock contact surface, calculate the frictional force applied to the rock mass block when the compound slope of the waste dump has a circular arc sliding trend; On the condition of the force balance of the soil-rock contact surface, calculate the amount of soil stacking required when the three-dimensional extension dimension of the toe counterweight platform is 1 m based on the frictional force, the angle between the soil-rock contact surface and the vertical line, and the soil unit weight.

7. The method for determining the backpressure platform for preventing and controlling the coal fire area in the open-pit mine according to claim 1, wherein Based on the amount of soil stacking, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line, calculate the geometric parameters of the toe counterweight platform, including: Based on the amount of soil stacking, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line, calculate the height of the toe counterweight platform; Based on the amount of soil stacking and the height of the toe counterweight platform, calculate the width of the toe counterweight platform.

8. An anti-pressure platform determination device for preventing and controlling coal fire areas in open-pit mines, characterized in that, Including: An acquisition module for acquiring the geometric parameters of the two-dimensional profile of the compound slope of the waste dump and the physical and mechanical parameters of the waste soil mass; wherein, the geometric parameters include: the angle between the soil-rock contact surface and the vertical line, the slope angle of the waste dump slope, and the retaining wall height; the physical and mechanical parameters include: the soil unit weight, the internal friction angle of the soil, the friction angle of the soil-rock contact surface, and the soil cohesion; A first calculation module for calculating the earth pressure on the soil-rock contact surface based on the Coulomb earth pressure theory, the geometric parameters, and the physical and mechanical parameters; A second calculation module for calculating the amount of soil stacking required when the three-dimensional extension dimension of the toe counterweight platform is 1 m based on the earth pressure on the soil-rock contact surface, the friction angle of the soil-rock contact surface, the angle between the soil-rock contact surface and the vertical line, and the soil unit weight; wherein, the toe counterweight platform is used to weaken the shear action of the compound slope of the waste dump on the toe area; A third calculation module for taking the geometric shape condition that the two-dimensional profile is a parallelogram and the platform slope angle is the slope angle of the waste dump slope, and calculating the geometric parameters of the toe counterweight platform based on the amount of soil stacking, the slope angle of the waste dump slope, and the angle between the soil-rock contact surface and the vertical line.

9. An electronic device, comprising a memory and a processor, wherein a computer program capable of running on the processor is stored on the memory, characterized in that, When the processor executes the computer program, it implements the method for determining the backpressure platform for preventing and controlling coal fire areas in open-pit mines according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions, and when the computer instructions are executed by the processor, it implements the method for determining the backpressure platform for preventing and controlling coal fire areas in open-pit mines according to any one of claims 1 to 7.

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