Method for optimizing strength of high-temperature metal mine filling mining cemented filling body

Abstract

The invention discloses a method for optimizing the strength of a high-temperature metal mine filling mining cemented filling body. S1, obtaining a relational expression among the uniaxial compressive strength of the cemented filling body, the concentration and the cement-sand ratio; s2, obtaining a relational expression between the uniaxial compressive strength and the curing temperature; s3, constructing a mutual relationship among the uniaxial compressive strength of the cemented filling body, the curing temperature, the concentration and the cement-sand ratio; meanwhile, constructing a deep ore body three-dimensional numerical model; s4, dividing the ore body to be mined into ore chambers and ore pillars; s5, analyzing the stability of the stope; s6, a cemented filling body matching scheme meeting the strength requirement is obtained; s7, cost is reduced to the maximum extent under the condition that the safety condition is met; and S8, performing stope safety coefficient analysis and optimization calculation in the stoping process of the pillars with different mining depths according to the step S6, and obtaining optimal proportion parameters of the cemented filling body under different mining depth conditions. Mine production cost can be reduced to the maximum extent, and safe and efficient mining of the mine is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of filling mining, and in particular to a method for optimizing the strength of a cemented filling body in filling mining of a high-temperature metal ore. Background Art

[0002] During the mining process of metal mines, as the mining depth increases, the temperature of the original rock continues to rise. In response to the challenges faced by the modernization of deep resource mining, the backfill mining method has been widely used in deep areas due to its advantages such as low loss, low cost, utilization of waste, and effective control of ground pressure. After the cemented backfill is filled into the mining area, a hydration reaction occurs in the mining area to form a consolidated body with a certain strength. The change in temperature affects the hydration reaction rate, which in turn affects the consolidation characteristics of the hydration product. In addition, the ratio parameters of the cemented backfill are particularly important. When the concentration or the ash-sand ratio increases, the strength of the backfill increases, but the cost also increases; when the concentration or the ash-sand ratio decreases, the cost of the backfill decreases, and similarly, the strength decreases. Therefore, it is particularly important to optimize the strength of the cemented backfill and determine the optimal parameter ratio of the cemented backfill during the mining of high-temperature metal ores.

[0003] Patents with publication numbers CN111324950 A and CN111312344A proposed methods for optimizing the proportion of filling materials. They used indoor experiments to test parameters such as filling material concentration and ash-sand ratio, and established a filling material optimization model with indicators such as strength and volume expansion rate of the cemented filling body as constraints to achieve optimal proportioning parameters. The above-mentioned prior art mainly systematically analyzes the mechanical properties of the cemented filling body at a laboratory scale. However, during deep filling and mining in mines, the size of the stope is several meters large. Due to changes in the original rock temperature and the filling body stress state in the deep area, the change characteristics of the large-volume cemented filling body under different conditions are somewhat different from those of indoor tests. Its hydration process will show a different change pattern from that of small test blocks as the content of the reactants increases. The accuracy of determining the proportion of filling materials by relying solely on indoor tests is low. Summary of the invention

[0004] In order to overcome the above technical problems, the purpose of the present invention is to provide a method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal mines. This method can minimize the production costs of mines and achieve safe and efficient mining of mines. It can be combined with the actual situation on site to the greatest extent, and the research results are highly reliable, accurate and universal.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore, comprising the following steps;

[0007] S1: Set the value range of each filling ratio parameter in the cemented filling body, measure the uniaxial compressive strength of the cemented filling body, and obtain the relationship between the uniaxial compressive strength and the concentration and the lime-sand ratio through fitting analysis;

[0008] S2: Control the concentration and cement-sand ratio parameters of the cemented filling body, measure the uniaxial compressive strength of the cemented filling body at different curing temperatures, and obtain the relationship between the uniaxial compressive strength and the curing temperature through fitting analysis;

[0009] S3: Integrate S1 and S2 to construct the relationship between the uniaxial compressive strength of the cemented filling and the curing temperature, concentration, and lime-sand ratio; at the same time, construct a three-dimensional numerical model of the deep ore body, and apply the in-situ stress and initial temperature field through on-site measurements;

[0010] S4: The mining body to be mined is divided into chambers and pillars. The deformation and damage of the cemented filling body after the chamber is filled are analyzed first. The mechanical parameters of the cemented filling body are added based on the results obtained from indoor experiments. Then, the stability of the roof and side walls of the goaf is monitored after the pillars are mined.

[0011] S5: Introduce safety factors (including roof safety factor and side wall safety factor) to analyze the stability of the stope during the backfill mining process in S4;

[0012] S6: The minimum safety factor of the roof and sidewall of the pillar stope is obtained through simulation analysis, and the cemented filling ratio scheme that meets the strength requirements is obtained through iterative calculation;

[0013] S7: Calculate the cost of each mix ratio scheme that meets the requirements, and obtain the optimal mix ratio scheme of the cemented filling body by comparing the economic cost indicators, so as to minimize the cost while meeting the safety conditions;

[0014] S8: Calculate the strength requirement of cemented filling body for backfill mining at different depths, simulate the real original rock environment at different depths by changing the temperature field and stress field of the three-dimensional numerical model, analyze and optimize the safety factor of the mining area during the pillar recovery process at different mining depths according to S6, and obtain the optimal ratio parameters of cemented filling body under different mining depth conditions.

[0015] In S1, the filling ratio parameters in the cemented filling body include concentration and lime-sand ratio. The cemented filling body concentration is selected to be 65-72%, and the lime-sand ratio is selected to be 1:6-1:10, and a standard cylindrical sample with a diameter of 50 mm and a height of 100 mm is prepared.

[0016] The fixed curing age is 28 days and the curing temperature is 35°C.

[0017] In S1, when the curing temperature of the cemented filling body is fixed at 35°C, a polynomial is used to fit the uniaxial compressive strength, concentration and lime-sand ratio. The fitting formula is:

[0018] UCS=a1+a2x+a3y+a4x 2 +a5y 2 +a6xy (1)

[0019] Where UCS is the uniaxial compressive strength of the cemented backfill specimen; x is the concentration; y is the lime-sand ratio; a1, a2, a3, a4, a5, and a6 are all fitting coefficients, and the fitting process is carried out using origin software.

[0020] In S2, the concentration parameter of the cemented filling body is controlled to be 70%, the lime-sand ratio parameter is 1:6, the curing age is fixed to 28 days, and the uniaxial compressive strength of the cemented filling body is measured under the curing temperature of 20-60°C; when the concentration of the cemented filling body and the lime-sand ratio are fixed, the uniaxial compressive strength and the curing temperature are fitted by a polynomial, and the fitting formula is:

[0021] UCS=b1+b2K+b3K 2 (2)

[0022] In the formula, K is the curing temperature; b1, b2, and b3 are fitting coefficients, and the fitting process is performed using origin software;

[0023] In S3, the uniaxial compressive strength values ​​of cemented filling bodies with different curing temperatures (20-60°C), different concentrations (1:6-1:10), and different lime-sand ratios (65-72%) are obtained by formula (1) and formula (2), and a uniaxial compressive strength data set is constructed;

[0024] Construct a three-dimensional numerical model of a deep ore body, including the hanging wall, the footwall, and the ore body, and apply the initial ground stress to the model through the ground stress measurement results, and apply the mechanical parameters in the model based on the basic mechanical experiments of the hanging wall, the footwall, and the ore body;

[0025] Horizontal holes (at least 5 different depths) are drilled at different mining depths in the mining area. The depth of the horizontal holes shall not be less than 2m. Temperature sensors are arranged in the holes to collect temperature. The original rock temperature at different mining depths in the mining area is monitored, and the numerical model temperature field is applied based on the original rock temperature results.

[0026] In S4, the ore body is mined in two steps: chamber and pillar. The first step is to mine the chamber and fill it with cemented filling body after mining; the second step is to mine the pillar and fill it with low-strength cemented filling body after mining;

[0027] Stable mining of pillars is an important basis for ensuring the overall safety of the mining site. During the mining process, both sides of the pillars are cemented backfill bodies, and the backfill bodies need to solve the problem of "standing stable". The monitoring method is: monitoring points are set at the top of the pillars to conduct roof stability analysis. After the mining of the mine room is completed, monitoring points are arranged inside the backfill body to conduct backfill stability analysis. At the same time, stress and displacement monitoring is carried out on the sides of the backfill body, and finally an overall deformation analysis of the backfill body is formed.

[0028] The S5 is specifically as follows: the calculation method of the safety factor is the ratio of the ultimate bearing strength to the actual strength. In the two-step pillar mining process, the roof is the ore body and the surrounding rock of the upper plate, which produces tensile failure. The tensile strength of the roof is selected as the basis for judging the instability of the roof; and the side wall is the cemented filling body after the mining of the mine room, which produces shear failure. The compressive strength of the filling body is selected as the basis for judging the instability of the side wall. The specific safety factor judgment relationship is,

[0029]

[0030] In the formula, F st is the roof safety factor; s t is the ultimate bearing strength of the roof ore body or surrounding rock; s tmax is the maximum tensile stress of the top plate from the numerical simulation results; F sc is the safety factor of the side gang; s t is the ultimate bearing strength of the cemented filling body on the sidewall; s tmax The maximum compressive stress of the sidewall is the result of numerical simulation;

[0031] The S6 is specifically: in order to optimize the parameters of the cemented filling body, reduce the filling cost while ensuring the strength requirements, control the safety factor within the range of 1.2 to 1.5, and obtain the minimum safety factor of the roof and side walls of the pillar mining area through simulation results. When the minimum safety factor is greater than 1.5, reduce the mechanical parameters of the cemented filling body and re-simulate the calculation; when the minimum safety factor is less than 1.2, increase the mechanical parameters of the cemented filling body and re-simulate the calculation.

[0032] Beneficial effects of the present invention:

[0033] 1) Under the premise of meeting the safety production of mines, the optimal cemented filling parameters are selected through economic cost, which can minimize the production cost of mines and realize safe and efficient mining of mines;

[0034] 2) Based on the indoor mechanical test results of cemented filling, the results are applied to the numerical simulation research of the mine site, combining the actual site conditions to the greatest extent, and the research results are more reliable;

[0035] 3) The stress field and temperature field of deep mining are taken into account in the numerical simulation process, and the change characteristics of the mining area under the action of force-heat coupling are realized. The simulation environment is closer to the actual situation, which improves the accuracy of the results;

[0036] 4) The field analysis is mainly based on numerical simulation. After the model is constructed, the simulation of different mining depths can be achieved by adjusting the temperature field and stress field parameter values. The operation method is simple and can accurately obtain the optimal ratio parameters of cemented filling bodies under different depth conditions, with strong universality. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a tailings particle size distribution diagram of an embodiment of the present invention;

[0038] Figure 2 This is a data set of uniaxial compressive strength of cemented filling body according to an embodiment of the present invention;

[0039] Figure 3 Constructing a three-dimensional model for numerical calculation of an embodiment of the present invention;

[0040] Figure 4 The initial stress field and temperature field of the model of the embodiment of the present invention;

[0041] Figure 5 It is the tensile stress monitoring of the roof of the pillar mining field according to the embodiment of the present invention;

[0042] Figure 6 This is the stress monitoring of the sidewall of the pillar recovery filling body according to the embodiment of the present invention;

[0043] Figure 7 This is a flow chart of strength optimization of cemented filling body according to an embodiment of the present invention;

[0044] Figure 8 This is a graph showing the change in safety factor of the pillar mining field when the original rock temperature is 35°C in an embodiment of the present invention;

[0045] Fig. 9 It is the safety factor of the pillar recovery stope under different temperature conditions in deep well mining according to the embodiment of the present invention. DETAILED DESCRIPTION

[0046] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0047] A method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore, comprising the following steps;

[0048] 1. Prepare cemented filling body. The cementitious material is 42.5R ordinary Portland cement. The tailings are the waste from a gold mine after ore dressing. They are obtained after drying and grinding. The tailings particle size after grinding is less than 1mm. The particle size distribution of the tailings is shown in Figure 1 , the cumulative 50% particle size of tailings d50 The diameter of the sand is 332.66 mm, which is coarse tailings; the curvature coefficient is 1.59, the unevenness coefficient is 5.91, and the continuity of particle size distribution is good; the mixing water is the tap water in the laboratory;

[0049] 2. The cemented filling concentrations were selected to be 65%, 68%, 70%, and 72%, and the lime-sand ratios were 1:6, 1:8, and 1:10, respectively. Standard cylindrical specimens with a diameter of 50 mm and a height of 100 mm were prepared. The curing age was fixed at 28 days and the curing temperature was 35°C. The uniaxial compressive strength of the cemented filling was measured. The results are shown in Table 1.

[0050] Table 1 Uniaxial compressive strength of cemented filling at 35℃-28d

[0051]

[0052] 3. The relationship between the uniaxial compressive strength of the cemented filling and the concentration and the lime-sand ratio was obtained through fitting analysis. The fitting process was carried out using origin software. The results are shown below:

[0053]

[0054] Where, UCS is the uniaxial compressive strength of the cemented backfill specimen; x is the concentration; y is the lime-sand ratio;

[0055] 4. The cemented filling concentration was fixed at 70%, the lime-sand ratio was 1:6, the curing temperature was changed to 20°C, 30°C, 40°C, 50°C, and 60°C, and the curing age was fixed at 28 days. The uniaxial compressive strength of the cemented filling was measured. The results are shown in Table 2.

[0056] Table 2 Uniaxial compressive strength of cemented filling at different curing temperatures at 28 days

[0057]

[0058] 5. The relationship between the uniaxial compressive strength of the cemented filling and the curing temperature was obtained through fitting analysis. The fitting process was performed using origin software. The results are shown below:

[0059]

[0060] Where K is the curing temperature;

[0061] 6. Using formula (1) and formula (2), we can obtain the uniaxial compressive strength values ​​of cemented filling bodies with different curing temperatures (20-60°C), different concentrations (1:6-1:10), and different lime-sand ratios (65-72%), and construct a uniaxial compressive strength data set. The specific results are as follows: Figure 2 As shown;

[0062] 7. A segment in the middle section of -825m of a gold mine was selected for simulation analysis. A segmented model was constructed according to the characteristics of the ore body. The bottom elevation of the first layer was set to -825m, the top elevation of the fourth layer was set to -805m, the true thickness of the ore body was 5.5m, the dip angle was 30°, and 3 mine rooms and 2 ore pillars were arranged in each layer. The mine rooms and ore pillars were arranged at intervals perpendicular to the ore body trend. Figure 3 As shown;

[0063] 8. According to the ground stress measurement results of the mining area, the maximum horizontal principal stress in the mining area is perpendicular to the ore body strike. The model principal stress is applied according to formula (3).

[0064]

[0065] In the formula, s X is the maximum principal stress, and its direction is perpendicular to the strike of the ore body; s Y is the minimum principal stress, and its direction is consistent with the strike of the ore body; s Z is the vertical stress; H is the burial depth;

[0066] 9. Drill horizontal holes at different mining depths in the mining area (at least 5 different depths). The depth of the horizontal holes shall not be less than 2m. Arrange temperature sensors in the holes for temperature collection. By monitoring and collecting the original rock temperature at different depths in the mining area, the change formula of the original rock temperature in the mining area is obtained as follows:

[0067] K=15.686+0.022H (4)

[0068] 10. According to the constructed three-dimensional model, the ground stress at the bottom of the model is calculated as follows: s X 62.78MPa,s Y 20.06MPa,s Z is 22.47MPa; the bottom temperature of the model is 34.72℃, and the top temperature is 32.52℃. After the initial equilibrium of the model, the initial stress field and temperature field are obtained, such as Figure 4 As shown;

[0069] 11. The ore and rock in the model all obey the Mohr-Coulomb failure criterion, and the failure criterion of cemented filling body adopts FLAC 3D According to the hydration-Drucker-Prager criterion in the calculation model, the cemented filling body parameter ratio is first determined as follows: concentration 70%, lime-sand ratio 1:6; the specific physical and mechanical parameters are shown in the following table.

[0070] Table 3 Mechanical parameter assignment of mining area

[0071]

[0072] Table 4 Assignment of thermal parameters of mining area

[0073]

[0074] 12. Divide the ore body to be mined into two steps: chamber and pillar. Design the first step to mine the chamber, and fill it with cemented filling body after mining; the second step to mine the pillar, and fill it with low-strength cemented filling body after mining;

[0075] 13. Analyze the deformation and damage of the cemented filling body after the first step of the mine room filling. After the second step of the ore pillar mining, monitor the stability of the roof and side walls of the empty area. The roof is rock and the side walls are cemented filling bodies. Arrange monitoring points to obtain the maximum stress values ​​of the roof and side walls. The results are as follows: Figure 5 , Figure 6 As shown;

[0076] 14. As Fig. 9 As shown in the figure, the safety factor (including roof safety factor and side wall safety factor) is introduced to analyze the stability of the stope during the backfill mining process. During the pillar mining process, the roof is the ore body and the surrounding rock of the upper plate, which mainly produces tensile failure. The tensile strength of the roof is selected as the basis for judging the instability of the roof, and 1.49MPa is determined as the tensile strength of the roof; while the side wall is the cemented backfill after the mining of the mine room, which mainly produces shear failure. The compressive strength of the backfill is selected as the basis for judging the instability of the side wall, and the compressive strength of the cemented backfill is determined to be 2.03MPa. The specific safety factor judgment relationship is,

[0077]

[0078] In the formula, F st is the roof safety factor; s t is the ultimate bearing strength of the roof ore body or surrounding rock; s tmax is the maximum tensile stress of the top plate from the numerical simulation results; F sc is the safety factor of the side gang; s t is the ultimate bearing strength of the cemented filling body on the sidewall; s tmax The maximum compressive stress of the sidewall is the result of numerical simulation;

[0079] 15. A larger safety factor will increase the mining cost, while a smaller safety factor will increase the mining risk; optimize the parameters of the cemented filling body, reduce the filling cost while ensuring the strength requirements, and control the safety factor within the range of 1.2 to 1.5; Figure 7 The strength optimization process of the cemented filling body is used for calculation. When the minimum safety factor is greater than 1.5, the mechanical parameters of the cemented filling body are reduced and the simulation calculation is repeated. When the minimum safety factor is less than 1.2, the mechanical parameters of the cemented filling body are increased and the simulation calculation is repeated. The cemented filling body ratio scheme that meets the strength requirements is finally obtained through iterative calculation.

[0080] 16. Iterative calculations are performed to obtain the safety factor calculation results of the stope during pillar mining under different cementing filling ratio schemes. The safety factor change diagram of the stope under different cementing filling parameters during pillar mining is drawn based on the safety factor calculation values, such as Figure 8 As shown; as the concentration of cemented filling gradually increases, the safety factor of the mining area is also gradually increasing; as the lime-sand ratio of cemented filling gradually increases, the safety factor of the mining area is gradually increasing; the closer to the lower right corner of the safety factor change chart, the higher the safety factor value. Under safe, feasible and economically reasonable conditions, the filling ratio schemes that meet the safety factor requirements mainly include the following four: ① lime-sand ratio 1:8, concentration 72%; ② lime-sand ratio 1:8, concentration 70%; ③ lime-sand ratio 1:6, concentration 70%; ④ lime-sand ratio 1:6, concentration 68%;

[0081] 17. The cost calculation of the four selected filling ratio schemes is shown in Table 5. When the cement-sand ratio is constant, when the concentration of the cemented filling increases by 2%, the unit consumption of cement increases by about 0.01t / m 3 When the concentration is determined to be 70%, the lime-sand ratio increases from 1:8 to 1:6, and the unit consumption of cement increases from 0.19t / m 3 Increased to 0.25t / m 3 , increased by about 0.06t / m 3 , while keeping the lime-sand ratio low, appropriately increasing the cementing filling concentration can minimize the cost of cementing filling. Finally, it was determined that under the condition of original rock temperature of 35℃, the optimal ratio parameters of cementing filling were lime-sand ratio of 1:8 and concentration of 70%;

[0082] Table 5 Cost calculation of cemented filling body under different schemes

[0083]

[0084] 18. The temperature field of the three-dimensional numerical model is changed to 40, 45, 50, 55, and 60 °C respectively. According to formula (4), the corresponding mining depths are calculated to be 1100m, 1330m, 1560m, 1780m, and 2010m. At the same time, the stress field is applied according to formula (3), and the safety factor of the mining area during the pillar recovery process at different mining depths is analyzed. The mining intensity requirements of the backfill method at different deep locations can be obtained, such as Figure 8 As shown in Table 6, the optimal ratio parameters of cemented filling body under different depth conditions are obtained.

[0085] Table 6 Strength requirements of cemented filling bodies for deep well mining

[0086]

[0087]

[0088] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore, characterized in that: The steps include: S1: Set the value range of each filling ratio parameter in the cemented filling body, measure the uniaxial compressive strength of the cemented filling body, and obtain the relationship between the uniaxial compressive strength and the concentration and the lime-sand ratio through fitting analysis; S2: Control the concentration and cement-sand ratio parameters of the cemented filling body, measure the uniaxial compressive strength of the cemented filling body at different curing temperatures, and obtain the relationship between the uniaxial compressive strength and the curing temperature through fitting analysis; S3: Integrate S1 and S2 to construct the relationship between the uniaxial compressive strength of the cemented filling and the curing temperature, concentration, and lime-sand ratio; at the same time, construct a three-dimensional numerical model of the deep ore body, and apply the in-situ stress and initial temperature field through on-site measurements; S4: Divide the body to be mined into two steps: chamber and pillar. Analyze the deformation and damage of the cemented filling body after the chamber is filled in step 1. The mechanical parameters of the cemented filling body are added based on the results obtained from indoor experiments. Then, monitor the stability of the roof and side walls of the goaf after the pillar is mined. S5: Introduce safety factor to analyze the stability of the stope during the backfill mining process in S4; S6: The minimum safety factor of the roof and sidewall of the pillar stope is obtained through simulation analysis, and the cemented filling ratio scheme that meets the strength requirements is obtained through iterative calculation; S7: Calculate the cost of each mix ratio scheme that meets the requirements, and obtain the optimal mix ratio scheme of the cemented filling body by comparing the economic cost indicators, so as to minimize the cost while meeting the safety conditions; S8; Calculate the strength requirement of cemented filling body for backfilling at different depths, simulate the real original rock environment at different depths by changing the temperature field and stress field of the three-dimensional numerical model, analyze and optimize the safety factor of the mining area during the pillar recovery process at different mining depths according to S6, and obtain the optimal ratio parameters of cemented filling body under different mining depth conditions.

2. The method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore according to claim 1 is characterized in that: In S1, the filling ratio parameters in the cemented filling body include concentration and lime-sand ratio. The cemented filling body concentration is selected to be 65-72%, the lime-sand ratio is selected to be 1:6-1:10, and a standard cylindrical sample with a diameter of 50 mm and a height of 100 mm is prepared; The fixed curing age is 28 days and the curing temperature is 35°C.

3. The method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore according to claim 2 is characterized in that: In S1, when the curing temperature of the cemented filling body is fixed at 35°C, a polynomial is used to fit the uniaxial compressive strength, concentration and lime-sand ratio. The fitting formula is: <h2 style=";text-align:left;direction:ltr">UCS = a1 + a2x + a3y + a4x<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> +a5y<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> +a6xy (1) Where UCS is the uniaxial compressive strength of the cemented backfill specimen; x is the concentration; y is the lime-sand ratio; a1, a2, a3, a4, a5, and a6 are all fitting coefficients, and the fitting process is carried out using origin software.

4. The method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore according to claim 3 is characterized in that: In S2, the concentration parameter of the cemented filling body is controlled to be 70%, the lime-sand ratio parameter is 1:6, the curing age is fixed to 28 days, and the uniaxial compressive strength of the cemented filling body is measured under the curing temperature of 20-60°C; when the concentration of the cemented filling body and the lime-sand ratio are fixed, the uniaxial compressive strength and the curing temperature are fitted by a polynomial, and the fitting formula is: UCS=b1+b2K+b3K 2 (2) Where K is the curing temperature; b1, b2, and b3 are all fitting coefficients, and the fitting process is performed using origin software.

5. The method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore according to claim 4, characterized in that: In S3, the uniaxial compressive strength values ​​of cemented filling bodies with different curing temperatures (20-60°C), different concentrations (1:6-1:10), and different lime-sand ratios (65-72%) are obtained by formula (1) and formula (2), and a uniaxial compressive strength data set is constructed; Construct a three-dimensional numerical model of a deep ore body, including the hanging wall, the footwall, and the ore body, and apply the initial ground stress to the model through the ground stress measurement results, and apply the mechanical parameters in the model based on the basic mechanical experiments of the hanging wall, the footwall, and the ore body; Horizontal holes are drilled at different mining depths in the mining area. The depth of the horizontal holes shall not be less than 2m. Temperature sensors are arranged in the holes to collect temperature. The original rock temperature at different mining depths in the mining area is monitored, and the numerical model temperature field is applied based on the original rock temperature results.

6. The method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore according to claim 1, characterized in that: In said S4, step 1 is to mine the chamber, and after mining, fill it with cemented filling body; step 2 is to mine the column, and after mining, fill it with low-strength cemented filling body; During the mining process, both sides of the pillar are cemented filling bodies. The monitoring method is: Monitoring points are set at the top of the pillars to analyze the stability of the roof. After the mining of the mine room is completed, monitoring points are arranged inside the filling body to analyze the stability of the filling body. At the same time, stress and displacement monitoring are carried out on the sides of the filling body, ultimately forming an overall deformation analysis of the filling body.

7. A method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore according to claim 6, characterized in that: The S5 is specifically as follows: the calculation method of the safety factor is the ratio of the ultimate bearing strength to the actual strength. In the process of mining the pillars in step 2, the roof is the ore body and the surrounding rock of the upper plate, which produces tensile failure. The tensile strength of the roof is selected as the basis for judging the instability of the roof; and the side wall is the cemented filling body after the mining of the mine room, which produces shear failure. The compressive strength of the filling body is selected as the basis for judging the instability of the side wall. The specific safety factor judgment relationship is, In the formula, F st is the roof safety factor; s t is the ultimate bearing strength of the roof ore body or surrounding rock; s tmax is the maximum tensile stress of the top plate from the numerical simulation results; F sc is the safety factor of the side gang; s t is the ultimate bearing strength of the cemented filling body on the sidewall; s tmax is the maximum compressive stress on the edge of the numerical simulation result.

8. The method for optimizing the strength of cemented filling bodies in filling mining of high-temperature metal ore according to claim 1, characterized in that: The S6 is specifically: controlling the safety factor within the range of 1.2 to 1.5, obtaining the minimum safety factor of the pillar stope roof and sidewall through simulation results, and when the minimum safety factor is greater than 1.5, reducing the mechanical parameters of the cemented filling body and re-simulating and calculating; When the minimum safety factor is less than 1.2, the mechanical parameters of the cemented filling body are increased and the simulation calculation is repeated.

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