An open-pit coal mine bedding fracture structure rock mass controlled mining method

Abstract

The application discloses a kind of open coal mine bedding fragmentation structure rock mass control mining method, limit equilibrium method is used to check the overall and local slope stability coefficient of outcrop area for bedding fragmentation structure rock mass, while meeting the overall and local slope stability coefficient requirements, obtain slope parameters, then coal resources are mined through slope parameters;After coal resources recovery, limit equilibrium method is also used to check the slope stability coefficient of internal discharge pressure foot, while meeting the slope stability coefficient requirements of internal discharge pressure foot, obtain the slope parameters of internal discharge pressure foot, then internal discharge pressure foot is carried out through the slope parameters of internal discharge pressure foot;More secure slope parameters are obtained by continuous checking of limit equilibrium method, thereby improving production safety and coal resources recovery rate, and internal discharge pressure foot improves the overall and local slope stability, to ensure that the slope is always in a stable and controllable state.

Description

Technical Field

[0001] This invention relates to the field of controlled mining technology in open-pit coal mines, specifically to a method for controlled mining of bedding-parallel fractured rock masses in open-pit coal mines. Background Technology

[0002] Existing preliminary designs for open-pit coal mines can provide medium- to long-term mining planning and guidance, but they have the following drawbacks:

[0003] 1. Because the preliminary design is based on the exploration results, the exploration accuracy is insufficient to meet the actual production needs, resulting in stripping waste and economic losses.

[0004] 2. Due to unclear geological conditions in the outcrop area and unreasonable slope parameter settings, there are disadvantages such as slope collapse and coal seam floor slippage and deformation. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention aims to provide a controlled mining method for bedding-parallel fractured rock masses in open-pit coal mines. For the outcrop area of ​​the bedding-parallel fractured rock mass, the method calculates the slope stability coefficient using the limit equilibrium method, determines the slope parameters, and then proceeds with coal mining. Furthermore, the method calculates the parameters of the inner drainage foot slope using the limit equilibrium method, determines the inner drainage foot slope parameters, and then proceeds with the inner drainage foot. This method features guaranteed slope safety and improved coal recovery rate, filling a gap in controlled mining technology for open-pit coal mines.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines, specifically including the following steps:

[0008] Step 1: Determine that the outcrop area is a bedding-parallel fractured rock mass;

[0009] Step 2: Set slope parameters;

[0010] Step 3: Use the limit equilibrium method to verify the overall slope stability coefficient. If the verification result is less than 1.05, return to Step 2 to reset the slope parameters.

[0011] Step 4: Use the limit equilibrium method to verify the local slope stability coefficient. If the verification result is less than 1.00, return to Step 2 to reset the slope parameters.

[0012] Step 5: Mining of coal resources in the outcrop area;

[0013] Step 6: Set the parameters for the inner drainage foot slope;

[0014] Step 7: Use the limit equilibrium method to verify the stability coefficient of the inner drainage toe slope. If the verification result is less than 1.10, return to step 6 to reset the inner drainage toe slope parameters.

[0015] Step 8: Inner pressure foot.

[0016] The first step is as follows: through comprehensive exploration of "geophysical exploration + drilling" and combined with physical and mechanical tests, the outcrop area is determined to be a bedding fractured rock mass;

[0017] Geophysical exploration specifically involves shallow seismic exploration. Based on reconnaissance and previous geological data, the number of seismic profiles, the length of each seismic profile, and the azimuth angle of the seismic profile are determined.

[0018] The drilling is specifically a supplementary engineering geological exploration of the outcrop area. Based on the geophysical exploration results, the number of exploration lines to be laid out and the number of boreholes to be laid out on each exploration line will be determined.

[0019] The physical and mechanical tests specifically include: uniaxial compressive strength, shear strength, tensile strength, bulk density, and moisture content tests;

[0020] Based on the geological conditions of the open-pit coal mine and the existing boreholes, a geophysical exploration plan was determined and construction was organized. First, the drilling plan was determined and construction was organized based on the geophysical exploration results. Then, physical and mechanical tests were conducted on the core samples taken from the drilling. Finally, the instability mechanism of the bedding fractured rock mass and slope in the outcrop area was determined based on the results of geophysical exploration, drilling, and physical and mechanical tests.

[0021] The slope parameters in step two specifically include: step height, step slope angle, and step flat width.

[0022] The overall slope in step three specifically refers to the area where the surface meets the coal and rock boundary at the outcrop.

[0023] The local slope in step four specifically refers to the coal-rock interface area in the outcrop region.

[0024] Step five specifically involves excavating from top to bottom according to the slope parameters set in step two, ultimately forming the designated slope.

[0025] The specific parameters of the inner footing slope in step six include: footing step height, footing plate width, number of footing steps, and footing step slope angle.

[0026] The slope angle of the footrest step is specifically set as the angle of repose.

[0027] Step eight specifically involves: according to the inner footing slope parameters set in step six, the inner footing is installed from bottom to top, ultimately forming the set inner footing slope.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0029] 1. By using the limit equilibrium method to verify the overall slope stability and local slope stability under different slope parameters, while meeting the requirements for overall slope stability and local slope stability, the slope parameters are determined. Coal resource mining is carried out based on these slope parameters, thereby ensuring slope safety and stability, ensuring safe production, and achieving the effect of preventing slope disasters.

[0030] 2. By using the limit equilibrium method to verify the overall slope stability and local slope stability under different slope parameters, the slope parameters are determined while meeting the requirements for overall slope stability and local slope stability. This yields the maximum mining data, which is then used to mine coal resources, successfully recover coal resources, improve the coal recovery rate, and ultimately increase economic benefits.

[0031] 3. The stability of the inner slope under different inner slope parameters is verified by the limit equilibrium algorithm. While meeting the stability requirements of the inner slope, the inner slope parameters are determined. The inner slope is then constructed according to these parameters to improve the overall and local slope stability and ensure that the slope is always in a stable and controllable state. Attached Figure Description

[0032] Figure 1 This is a flowchart of the controlled mining method of the present invention. Detailed Implementation

[0033] The structural and working principles of the present invention will be described in detail below with reference to the accompanying drawings.

[0034] See Figure 1 A method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines, specifically including the following steps:

[0035] Step 1: Determine that the outcrop area is a bedding-parallel fractured rock mass;

[0036] Step 2: Set slope parameters to provide basic data for subsequent verification calculations;

[0037] Step 3: Use the limit equilibrium method to verify the overall slope stability coefficient. If the verification result is less than 1.05, return to Step 2 to reset the slope parameters. After extraction, the overall slope stability coefficient should not be less than 1.05.

[0038] Step 4: Use the limit equilibrium method to verify the local slope stability coefficient. If the verification result is less than 1.00, return to Step 2 to reset the slope parameters. After extraction, the local slope stability coefficient should not be less than 1.00.

[0039] Step 5: Mining of coal resources in the outcrop area;

[0040] Step 6: Set the parameters of the inner drainage foot slope to provide basic data for subsequent verification calculations;

[0041] Step 7: Use the limit equilibrium method to verify the stability coefficient of the inner drainage foot slope. If the verification result is less than 1.10, return to step 6 to reset the inner drainage foot slope parameters. After the inner drainage foot is installed, the stability coefficient of the inner drainage foot slope should not be less than 1.10.

[0042] Step 8: Inner pressure foot.

[0043] The first step is as follows: through comprehensive exploration of "geophysical exploration + drilling" and combined with physical and mechanical tests, the outcrop area is determined to be a bedding fractured rock mass;

[0044] Geophysical exploration specifically involves shallow seismic exploration. Based on reconnaissance and previous geological data, the number of seismic profiles, the length of each seismic profile, and the azimuth angle of the seismic profile are determined.

[0045] The drilling is specifically a supplementary engineering geological exploration of the outcrop area. Based on the geophysical exploration results, the number of exploration lines to be laid out and the number of boreholes to be laid out on each exploration line will be determined.

[0046] The physical and mechanical tests specifically include: uniaxial compressive strength, shear strength, tensile strength, bulk density, and moisture content tests;

[0047] Based on the geological conditions of the open-pit coal mine and the existing boreholes, a geophysical exploration plan was determined and construction was organized. First, the drilling plan was determined and construction was organized based on the geophysical exploration results. Then, physical and mechanical tests were conducted on the core samples taken from the drilling. Finally, the instability mechanism of the bedding fractured rock mass and slope in the outcrop area was determined based on the results of geophysical exploration, drilling, and physical and mechanical tests.

[0048] The slope parameters in step two specifically include: step height, step slope angle, and step flat width.

[0049] The overall slope in step three specifically refers to the area where the surface meets the coal and rock boundary at the outcrop.

[0050] The local slope in step four specifically refers to the coal-rock interface area in the outcrop region.

[0051] Step five specifically involves excavating from top to bottom according to the slope parameters set in step two, ultimately forming the designated slope.

[0052] The specific parameters of the inner footing slope in step six include: footing step height, footing plate width, number of footing steps, and footing step slope angle.

[0053] The slope angle of the foot step is specifically set as the natural angle of repose. The natural angle of repose ensures that the foot step itself is in a stable state, thereby providing anti-slip force for the upper slope and improving the overall and local slope stability.

[0054] Step eight specifically involves: according to the inner footing slope parameters set in step six, the inner footing is installed from bottom to top, ultimately forming the set inner footing slope.

Claims

1. A method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines, characterized in that: Specifically, the following steps are included: Step 1: Through comprehensive exploration using geophysical exploration and drilling, combined with physical and mechanical tests, the outcrop area was determined to be a bedding-parallel fractured rock mass. Geophysical exploration specifically involves shallow seismic exploration. Based on reconnaissance and previous geological data, the number of seismic profiles, the length of each seismic profile, and the azimuth angle of the seismic profile are determined. The drilling is specifically a supplementary engineering geological exploration of the outcrop area. Based on the geophysical exploration results, the number of exploration lines to be laid out and the number of boreholes to be laid out on each exploration line will be determined. The physical and mechanical tests specifically include: uniaxial compressive strength, shear strength, tensile strength, bulk density, and moisture content tests; Based on the geological conditions of the open-pit coal mine and the existing boreholes, a geophysical exploration plan was determined and construction was organized. First, the drilling plan was determined and construction was organized based on the geophysical exploration results. Then, physical and mechanical tests were conducted on the core samples taken from the drilling. Finally, the instability mechanism of the bedding fractured rock mass and slope in the outcrop area was determined based on the results of geophysical exploration, drilling, and physical and mechanical tests. Step 2: Set slope parameters; Step 3: Use the limit equilibrium method to verify the overall slope stability coefficient. If the verification result is less than 1.05, return to Step 2 to reset the slope parameters. Step 4: Use the limit equilibrium method to verify the local slope stability coefficient. If the verification result is less than 1.00, return to Step 2 to reset the slope parameters. Step 5: Mining of coal resources in the outcrop area; Step 6: Set the parameters for the inner drainage foot slope; Step 7: Use the limit equilibrium method to verify the stability coefficient of the inner drainage toe slope. If the verification result is less than 1.10, return to step 6 to reset the inner drainage toe slope parameters. Step 8: Inner pressure foot.

2. The method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines according to claim 1, characterized in that: The slope parameters in step two specifically include: step height, step slope angle, and step flat width.

3. The method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines according to claim 1, characterized in that: The overall slope in step three specifically refers to the area where the surface meets the coal and rock boundary at the outcrop.

4. The method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines according to claim 1, characterized in that: The local slope in step four specifically refers to the coal-rock interface area in the outcrop region.

5. The method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines according to claim 1, characterized in that: Step five specifically involves excavating from top to bottom according to the slope parameters set in step two, ultimately forming the designated slope.

6. The method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines according to claim 1, characterized in that: The specific parameters of the inner footing slope in step six include: footing step height, footing plate width, number of footing steps, and footing step slope angle.

7. The method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines according to claim 6, characterized in that: The slope angle of the footrest step is specifically set as the angle of repose.

8. The method for controlled mining of bedding-parallel fractured rock mass in open-pit coal mines according to claim 1, characterized in that: Step eight specifically involves: according to the inner footing slope parameters set in step six, the inner footing is installed from bottom to top, ultimately forming the set inner footing slope.

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