Sequential access method stope safety span determination method
The safety span of the mining site is determined by the sequential approach method, combined with the mining site stability evaluation and span adjustment coefficient, the problem of unreasonable mining span design in the traditional method is solved, and more efficient and safe mining production is achieved.
Patent Information
- Application Number
- CN202411246865.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-06
- Publication Date
- 2025-02-07
AI Technical Summary
During the mining process, traditional methods are difficult to accurately determine the span of the mining site, resulting in unreasonable production scale or safety hazards, increasing the risk of resource losses and safety accidents.
The sequential approach method is adopted to determine the set of factors influencing the safety span of the mining site, calculate the stability evaluation set of each region, and establish the relationship between the stability evaluation set and the span adjustment coefficient, and finally calculate the safety by combining the Mathews stable chart method. Span value.
This method can shorten the test cycle while increasing the production scale of the mining site, reduce the risk of resource losses and safety accidents, and provide a more scientific and reasonable mining site span design.
Smart Images
Figure CN119397156A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of stope structure parameter design, and in particular to a method for determining a stope safety span using a sequential approach method. Background Art
[0002] Ore bodies with complex shapes, large thickness variations, and high value often adopt the upward approach filling mining method. The stope span is the main parameter of the stope structure of this type of mining method. Whether its selection is reasonable determines the safety and efficiency of mining. When designing a stope, empirical analogy is often used. However, the underground conditions of each mine are quite different. It is easy to cause some problems by selecting the stope span based on experience. For example, if the selected parameters are too small, the production scale of the stope will be small and the production cost will increase; if the selected parameters are too large, the stope will be more likely to become unstable, resulting in production safety accidents or causing the loss of ore resources. In practice, some mines have obtained a reasonable stope span through continuous experiments, but this method has a long test cycle, a wide range of test parameter selection, and unreasonable parameter selection will also bring safety risks and resource loss risks. Summary of the invention
[0003] The present invention is made to solve the above-mentioned technical problems, and its purpose is to provide a method for determining the safe span of a mining field using a sequential approach method. The safe span obtained by this method can not only ensure the safety of mining field production, but also can greatly increase the scale of mining field production and reduce resource losses.
[0004] In order to achieve the above object, the present invention provides a method for determining the safety span of a stope by a sequential approach method, comprising the following steps:
[0005] Determine the influencing factor set U of the stope safety span i ;
[0006] Based on the influencing factors, calculate the stability evaluation set V of each area in the stope j ;
[0007] Establish the stability judgment set V j The relationship between span adjustment coefficient d;
[0008] The initial span value of each area in the stope is calculated based on the Mathews stability chart method, and then multiplied by the span adjustment coefficient d of each area in the stope to obtain the safe span value of each area in the stope.
[0009] According to the above description and practice, the method for determining the safety span of the mining field by the sequential approach method described in the present invention calculates the stability evaluation level of each area based on the influencing factors related to the safety span in the mining field, and then establishes a relationship between it and the span adjustment coefficient, and finally multiplies it with the initial span value calculated by the Mathews stability chart method to obtain the final safety span value. Compared with the safety span value obtained by the traditional method, the safety span value obtained by this method has a shorter acquisition cycle, and can greatly increase the production scale of the mining field while ensuring production safety. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 The present invention is a flowchart of a method for determining a safe span of a mining area using a sequential approach method according to an embodiment of the present invention. DETAILED DESCRIPTION
[0011] The exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the disclosure will be more comprehensive and complete and fully convey the concepts of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0012] In this embodiment, a method for determining the safety span of a stope using a sequential approach method is disclosed, which is used to obtain the safety span value of each target area in the stope. Figure 1 As shown in the figure, the method for determining the safe span of the mining area by the sequential approach method mainly includes the following four steps:
[0013] Step S1: Determine the influencing factor set U of the stope safety span i .
[0014] Specifically, the influencing factor set U i =(U1, U2, U3, U4, U5), where U1 is the filling connection degree, U2 is the distance from the upper wall of the ore body, U3 is the cumulative width of the interlayer, U4 is the expansion rate of the surrounding rock when it comes into contact with water, and U5 is the degree of influence of multiple factors coupling.
[0015] These influencing factors have different importance in different areas of the stope for calculating the safety span, so each influencing factor needs to have a reasonable weight distribution. After actual test analysis, the weight of these influencing factors in each area of the stope is A ki Among them, A1 is the upper wall of the ore body in the mining area, A2 is the lower wall of the ore body in the mining area, A3 is the first ore belt in the mining area, A4 is the second ore belt in the mining area, and A5 is the third ore belt in the mining area.
[0016] For example, in a specific embodiment, the first mineral belt is a Py belt, the second mineral belt is a Zn belt, and the third mineral belt is a SW belt.
[0017]
[0018] Among them, the first row in the matrix represents the weight distribution method of the above five influencing factors in the upper plate area of the ore body in the mining area, where the weight of the surrounding rock water expansion rate is 1, and the weights of the other influencing factors are 0. For another example, the second row in the matrix represents the weight distribution method of the above five influencing factors in the lower plate area of the ore body in the mining area, where the weight of the filling connection degree is 0.2, the weight of the distance from the upper plate of the ore body is 0.2, the weight of the cumulative width of the interlayer is 0.2, the weight of the surrounding rock water expansion rate is 0.2, and the weight of the multi-factor coupling influence degree is 0.2.
[0019] Step S2: Calculate the stability evaluation set V of each area in the stope based on the influencing factors j .
[0020] Specifically, the stability evaluation set V j =(V1, V2, V3, V4, V5), where V1 to V5 are stability evaluation levels, V1 means very stable, V2 means relatively stable, V3 means generally stable, V4 means unstable, and V5 means very unstable. It should be noted that the five evaluation levels included in the evaluation set can not only be used to judge the overall stability level of a certain area, but also to judge the stability level of each factor in a certain area. In other words, the stability evaluation level standard can be applied to each influencing parameter and its comprehensive evaluation process in this application.
[0021] Based on the stability evaluation grade standard, the evaluation grade of the i-th evaluation factor of the k-th target area in the stope is V j The evaluation score is recorded as F kij ,in
[0022]
[0023]
[0024] It can be seen from the five formulas that in a target area of a stope, according to the specific values of the above five influencing factors, points can be assigned according to five evaluation levels, and the evaluation scores are 100, 80, 60, 40, and 20 from high to low.
[0025] Among them, the water expansion rate of surrounding rock refers to the ratio of the increased volume of surrounding rock to the original volume after it expands with water. The evaluation of the degree of multi-factor coupling influence is divided based on the sum of the evaluation scores of the above four influencing factors. Specifically, in a target area, when the sum of the evaluation scores of the four influencing factors U1, U2, U3, and U4 is greater than 360 points, the evaluation score of U5 is 100 points; when the sum of the evaluation scores of the four influencing factors U1, U2, U3, and U4 is greater than 320 points but not more than 360 points, the evaluation score of U5 is 80 points; when the sum of the evaluation scores of the four influencing factors U1, U2, U3, and U4 is greater than 280 points but not more than 320 points, the evaluation score of U5 is 60 points; when the sum of the evaluation scores of the four influencing factors U1, U2, U3, and U4 is greater than 240 points but not more than 280 points, the evaluation score of U5 is 40 points; when the sum of the evaluation scores of the four influencing factors U1, U2, U3, and U4 is less than 240 points, the evaluation score of U5 is 20 points.
[0026] The stability evaluation set V of each area in the calculation stope j When we first construct the influencing factor set U i and stability judgment set V j The single factor evaluation matrix R of the relationship between kij , then multiplied by the weight set A ki Obtain the fuzzy evaluation matrix B of the stope span in the target area, where
[0027]
[0028] In the formula, R kij represents the stability judgment set V of the i-th influencing factor of the k-target area j The membership degree of the jth element in , k represents the target area number; i represents the number of influencing factors of the kth target area; j represents the stability evaluation set V j The jth evaluation result in the fuzzy evaluation matrix B represents the stability evaluation set V of the k target area. j The membership of the jth element in , the stability evaluation level corresponding to the maximum membership in each target area is taken as the stability evaluation level of the target area. Through the above formula, it can be obtained which standard of the above five levels the stability evaluation level of a certain target area belongs to.
[0029] In the specific calculation process, the final B is a matrix of five rows and five columns, where each row represents a target area for the stability judgment set V j For example, when k is 2, if B2 is (000.200), it means that in the footwall area of the ore body of the stope, the stability level V j Take V3, whose stability is generally stable.
[0030] Step S3: Establish the stability evaluation set V j The relationship with the span adjustment coefficient d.
[0031] Under the premise of ensuring safety and maintaining a large production scale, after actual testing, the stability evaluation set V j The relationship with the span adjustment coefficient d is:
[0032]
[0033] For example, if the stability of the footwall area of the ore body in the mining area is generally stable, then when calculating the safety span in this area, the value range of the adjustment coefficient d of the safety span is 0.7 to 0.8.
[0034] Step S4: Calculate the initial span value of each area in the stope based on the Mathews stability chart method, and then multiply it by the span adjustment coefficient d of each area in the stope to obtain the safe span value of each area in the stope.
[0035] Among them, the calculation of the initial span value of each area in the stope based on the Mathews stability chart method is a prior art and will not be repeated here. The initial span value is multiplied by the span adjustment coefficient d to obtain the safety span value in the corresponding target area. Compared with the safety span value obtained by the traditional method, the safety span value obtained by this method has a shorter acquisition cycle and can greatly increase the production scale of the stope while ensuring production safety.
[0036] This method for determining the safety span of the mining area using the sequential approach method can obtain an accurate safety span of the mining area through a series of tests and calculations after the ore body is exposed, thus avoiding the need to continuously test and obtain a reasonable span during the mining process. For example, after the ore body is exposed by the mining area connecting road, the accurate safety span of each area can be obtained through this method, and the ore body mining area can be finely divided, which is conducive to improving the mining recovery rate and reducing loss and dilution. Compared with the traditional ore and rock classification method, it is more refined, reduces the error of subjective judgment, and the results of ore and rock stability classification are more accurate and objective.
[0037] The method for determining the safe span of a mining area using the sequential approach method is further explained below in conjunction with a specific mining area.
[0038] The degree of rock fragmentation, filling connection rate, ground stress, and groundwater have a great influence on the stability of the mining area. In this mining area, the surrounding rock has a prominent expansion rate when it encounters water, and the interlayers in different ore belts are intricate, which has a great impact on the stability of the surrounding rock of the mining area approach, resulting in prominent disasters such as surrounding rock deformation and roof collapse in the mining area approach. In addition, affected by the mine filling system and geological conditions, the filling body in the goaf cannot be connected to the top, resulting in the inability to effectively control the ground pressure in the mining area. As the approach is gradually mined from the upper wall of the ore body to the lower wall of the ore body, the area where the filling body in the goaf cannot be connected to the top is getting larger and larger, which seriously restricts the stability span of the mining area approach close to the lower wall of the ore body. In the process of selecting the span of the mining area approach in different ore belts, if the actual mining area span is determined only based on the results of the Mathews stability chart method, and the influence of factors such as the degree of connection, the location of the mining approach, and the interlayer situation on the span is ignored, it is bound to cause unreasonable span design and the inability to achieve safe mining of the ore body. In summary, taking into account five influencing factors, namely the degree of filling connection, the distance from the upper wall of the ore body, the cumulative width of the interlayer, the water expansion rate of the surrounding rock and the degree of multi-factor coupling, and considering a certain safety factor, on the basis of determining the approach span by the traditional graphical method, a method for determining the span reduction coefficient under different conditions is proposed, and the span of the mining access is optimized, in order to obtain a more scientific and reasonable span design.
[0039] That is, the influencing factor set U of the stope safety span is determined i =(U1, U2, U3, U4, U5), where U1 is the filling connection degree, U2 is the distance from the upper wall of the ore body, U3 is the cumulative width of the interlayer, U4 is the expansion rate of the surrounding rock when it comes into contact with water, and U5 is the degree of influence of multiple factors coupling.
[0040] Based on the analysis of the above-mentioned on-site conditions of the mining area, the engineering factors that affect the span of the mining area mainly consider the degree of filling connection, the distance from the upper wall of the ore body, the cumulative width of the interlayer, the water expansion rate of the surrounding rock, and the degree of influence of multiple factors coupling. The weights of these factors are assigned according to their importance, that is, the weight distribution of each factor is determined for subsequent comprehensive evaluation and calculation. Whether the weights of each factor are reasonable will directly determine the validity of the evaluation results. Generally, the weights can be determined by mathematical statistics, survey statistics, and hierarchical analysis. Since there are many factors that affect the span of the mining area, the reliability of calculating the weights of the evaluation factors using the above methods is not high, and it is very difficult. After simulation and actual testing, the weight ratios of each influencing factor in different ore and rock areas are assigned, which are recorded as the weight set A. ki The various ore and rock areas of the stope are A k , A k =(A1, A2, A3, A4, A5), where A1 is the upper wall of the ore body in the stope, A2 is the lower wall of the ore body in the stope, A3 is the Py zone in the stope, A4 is the Zn zone in the stope, and A5 is the SW zone in the stope. The weight of the influencing factors in each area of the stope is Aki .
[0041]
[0042] Specifically, the weight ratios of the above five influencing factors in different ore and rock areas in the mining area are shown in Table 1.
[0043] Table 1:
[0044]
[0045] In order to facilitate unified classification and evaluation, the impact analysis of each influencing factor on the stability of the stope is divided into five levels, namely, the stability evaluation set V j =(V1, V2, V3, V4, V5), where V1 to V5 are stability evaluation levels, V1 means very stable, V2 means relatively stable, V3 means generally stable, V4 means unstable, and V5 means very unstable.
[0046] Specifically, the evaluation criteria and corresponding evaluation scores when the above five influencing factors are evaluated according to the above five evaluation levels are shown in Tables 2 to 6 below.
[0047] Table 2:
[0048]
[0049] Table 3:
[0050]
[0051] Table 4:
[0052]
[0053] Table 5:
[0054]
[0055] Table 6:
[0056]
[0057] The evaluation scores in Tables 2 to 6 correspond from high to low to the five evaluation levels V1 to V5 in the above stability evaluation set.
[0058] It should be noted that, from the numerical simulation results of the on-site geological conditions, it can be seen that as the ore body is gradually mined from the upper plate to the lower plate, the ground pressure of the mining area gradually transfers to the unmined area near the lower plate of the ore body, and the stability of the roof becomes worse and worse. Therefore, if only a single mining span is used in the ore body area, it is bound to cause the roof of the access road near the lower plate of the ore body to collapse. As the mining proceeds, the amount of sinking of the mining access roof gradually increases, and the amount of sinking of the access roof near the lower plate of the ore body is the largest, which is less conducive to the stability of the roof. The actual distance between the mining access position and the surrounding rock of the upper plate of the ore body is used as the quantitative parameter of this indicator. The level of its influence on stability is the data shown in Table 3.
[0059] The above gives the factors affecting the safety span of a stope and the criteria for judging each factor. Based on this, the stability judgment set V of each area in the stope is calculated. j , the specific process is as follows:
[0060] First, we construct a set of influencing factors U i and stability judgment set V j The single factor evaluation matrix R of the relationship between kij , then multiplied by the weight set A ki Obtain the fuzzy evaluation matrix B of the stope span in the target area, where
[0061]
[0062] In the formula, R kij represents the stability judgment set V of the i-th influencing factor of the k-target area j The membership degree of the jth element in , k represents the target area number; i represents the number of influencing factors of the kth target area; j represents the stability evaluation set V j The jth evaluation result in the fuzzy evaluation matrix B represents the stability evaluation set V of the k target area. j The membership degree of the jth element in , and the stability judgment level corresponding to the maximum membership value in each target area is taken as the stability judgment level of the target area.
[0063] The specific evaluation results of each influencing factor based on the on-site conditions of the mining site are shown in Table 7.
[0064] Table 7:
[0065]
[0066] According to the data in Tables 1 to 7 and R kij The calculation formula can be used to obtain the single factor evaluation matrix in each target area of the stope, as follows:
[0067] The upper wall of the ore body,
[0068] The footwall of the ore body,
[0069] Py zone of the stope,
[0070] Zn zone in the mining area,
[0071] SW zone of the stope,
[0072] Afterwards, the single factor evaluation matrix of these target areas and the weight set A of each area are combined. ki By multiplying, we can get the fuzzy evaluation matrix B of the corresponding area. The values in the fuzzy evaluation matrix B represent the stability evaluation set V of the corresponding target area. j The membership degree of the jth element in , and the stability judgment level corresponding to the maximum membership value in each target area is taken as the stability judgment level of the target area.
[0073] Take the hanging wall area of the ore body in the stope as an example:
[0074]
[0075] The results are as follows: the membership of the ore body hanging area to very stable is V1 = 0; the membership to relatively stable is V2 = 0; the membership to generally stable is V3 = 0.2; the membership to unstable is V4 = 0; the membership to very unstable is V5 = 0. Therefore, the ore body hanging area has the highest membership to the third level (generally stable), and according to the principle of selection, it should be evaluated as generally stable.
[0076] Take the Py zone area of the stope as an example:
[0077]
[0078] The results are as follows: the membership of the Py band region to very stable is V1 = 0.099; the membership to relatively stable is V2 = 0.189; the membership to generally stable is V3 = 0; the membership to unstable is V4 = 0; the membership to very unstable is V5 = 0. Therefore, the Py band region has the highest membership to the second level (relatively stable) V2, and according to the principle of merit, it should be rated as relatively stable.
[0079] Similarly, the stability evaluation results of each target area are calculated and shown in Table 8 below.
[0080] Table 8:
[0081]
[0082] Finally, according to the stability evaluation results and the corresponding span adjustment coefficients, the initial span values of each area in the stope calculated based on the Mathews stability chart method were optimized to obtain the final safe span value.
[0083] Specifically, the stability evaluation set V j In this embodiment, the relationship between θ and the span adjustment coefficient d is as follows:
[0084]
[0085] Among them, when the stability evaluation level is V1 very stable, the corresponding span adjustment coefficient is 0.9 to 1.0;
[0086] When the stability evaluation level is V2, which is relatively stable, the corresponding span adjustment coefficient is 0.8 to 0.9;
[0087] When the stability evaluation level is V3 (generally stable), the corresponding span adjustment coefficient is 0.7 to 0.8;
[0088] When the stability evaluation level is V4 unstable, the corresponding span adjustment coefficient is 0.6 to 0.7;
[0089] When the stability evaluation level is V5, which is very unstable, the corresponding span adjustment coefficient is 0.5 to 0.6.
[0090] In addition, the initial span values of each target area in the stope calculated based on the Mathews stability chart method are shown in Table 9 below, and the corresponding optimized safe span values of each target area in the stope are shown in Table 9 below.
[0091] Table 9:
[0092]
[0093] Furthermore, based on the actual surrounding rock conditions of the stope, the stability evaluation set V j The relationship with the span adjustment coefficient d is as follows:
[0094]
[0095] Under this relationship, the optimized safety span of the upper plate area of the ore body is 3.62m; the optimized safety span of the lower plate area of the ore body is 3.26m; the optimized safety span of the Py belt area is 5.00m; the optimized safety span of the Zn belt area is 3.50m; and the optimized safety span of the SW belt area is 4.50m. Under these safety span values, the stope can achieve safe production operations and have a high ore recovery rate.
[0096] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.
Claims
1. A method for determining the safety span of a stope using a sequential approach method, characterized in that: include: Determine the influencing factor set U of the stope safety span i ; Based on the influencing factors, calculate the stability evaluation set V of each area in the stope j ; Establish the stability judgment set V j The relationship between the span adjustment coefficient d; The initial span value of each area in the stope is calculated based on the Mathews stability chart method, and then multiplied by the span adjustment coefficient d of each area in the stope to obtain the safe span value of each area in the stope.
2. The method for determining the safety span of a stope using a sequential approach method as claimed in claim 1, characterized in that: Influencing factor set U i =(U1, U2, U3, U4, U5), where U1 is the filling connection degree, U2 is the distance from the upper wall of the ore body, U3 is the cumulative width of the interlayer, U4 is the expansion rate of the surrounding rock when it comes into contact with water, and U5 is the degree of influence of multiple factors coupling.
3. The method for determining the safe span of a stope using the sequential approach method as claimed in claim 2, characterized in that: The various areas of the stope are A k , A k =(A1, A2, A3, A4, A5), where A1 is the upper wall of the ore body in the stope, A2 is the lower wall of the ore body in the stope, A3 is the first ore belt in the stope, A4 is the second ore belt in the stope, and A5 is the third ore belt in the stope. The weight of the influencing factors in each area of the stope is A ki .
4. The method for determining the safety span of a stope using a sequential approach method as claimed in claim 3, characterized in that: The first ore belt is the Py belt, the second ore belt is the Zn belt, and the third ore belt is the SW belt.
5. The method for determining the safety span of a stope using a sequential approach method as claimed in claim 4, characterized in that: The stability evaluation set V j =(V1, V2, V3, V4, V5), where V1 to V5 are stability evaluation levels, V1 means very stable, V2 means relatively stable, V3 means generally stable, V4 means unstable, and V5 means very unstable.
6. The method for determining the safety span of a stope using a sequential approach method as claimed in claim 5, characterized in that: The evaluation level of the i-th evaluation factor of the k-th target area is V j The evaluation score is F kij ,in 7. The method for determining the safety span of a stope using a sequential approach method as claimed in claim 6, characterized in that: Based on the influencing factors, calculate the stability evaluation set V of each area in the stope j include: Construct the influencing factor set U i and stability judgment set V j The single factor evaluation matrix R of the relationship between kij , then multiplied by the weight set A ki Obtain the fuzzy evaluation matrix B of the stope span in the target area, where In the formula, R kij represents the stability judgment set V of the i-th influencing factor of the k-target area j The membership degree of the jth element in , k represents the target area number; i represents the number of influencing factors of the kth target area; j represents the stability evaluation set V j The jth evaluation result in the fuzzy evaluation matrix B represents the stability evaluation set V of the k target area. j The membership degree of the jth element in , and the stability judgment level corresponding to the maximum membership value in each target area is taken as the stability judgment level of the target area.
8. The method for determining the safety span of a stope using the sequential approach method as claimed in claim 7, characterized in that: The stability evaluation set V j The relationship with the span adjustment coefficient d is:
9. The method for determining the safety span of a stope using a sequential approach method as claimed in claim 7, characterized in that: The stability evaluation set V j The relationship with the span adjustment coefficient d is: