Research method of broken ore body mining method

Abstract

The invention discloses a research method of a broken ore body mining method, which masters the mining history and current situation through mine site survey and data collection and analysis, and obtains the broken ore body mining result through indoor rock mechanical test, rock mass quality grading, rock mass parameter reduction and other means. According to the method, the rock mass mechanical parameters, capable of being used for numerical simulation analysis, of the broken ore body and the surrounding rock are obtained, then a three-dimensional mining model of a mine is established, stability analysis is conducted on the three-dimensional mining model through a finite difference method, and structural parameters and a charging method of a stope are obtained. And the stability and the safety can be better improved.

Description

Technical Field

[0001] The invention relates to the technical field of ore dressing, and in particular to a research method for a crushing ore body mining method. Background Art

[0002] Anhui Jinrisheng Mining Co., Ltd. Zhouyoufang Iron Mine has a designed production capacity of 4.5 million tons / year. Currently, there are three wells, 1# main well, 2# measure well, and 3# measure well, in normal production, with a production capacity of 3.3 million tons / year. Overall, the upper plate of the ore body south of the southern 4th line is relatively broken, and the upper plate surrounding rock and the ore body oxidation zone have a greater impact on the stability of the mining area; the upper plate and the mining area roof collapse phenomenon is serious during the mining process, and the support volume is large. Summary of the invention

[0003] The invention discloses a research method for a crushed ore body mining method to solve the defects of the prior art mentioned in the background technology.

[0004] To achieve the above object, the present invention provides the following technical solution: a research method for a crushing ore body mining method, comprising the following steps:

[0005] (1) Geological exploration of mining areas: analysis of the strata, structure, and development of magmatic rocks in the mining areas;

[0006] (2) Technical conditions for mining south of mine line 4: analysis of engineering geological conditions, hydrogeological conditions, and environmental geological conditions;

[0007] (3) Current situation survey: survey of buildings (structures) south of the 4# exploration line, surface displacement monitoring data, rock mass structural surface survey, and drilling and coring survey;

[0008] (4) Rock mechanics tests and parameters: rock physical properties test, rock uniaxial compressive strength test, rock uniaxial compression deformation test, rock tensile strength test, rock regular shear strength test, SCR value of structural surface characteristic grade, SR value of rock mass structure grade, GSI classification parameter determination, Hoek-Brown strength criterion;

[0009] (5) Optimization of single stope structural parameters: stope stability analysis based on rock mass quality classification, stope stability analysis based on numerical simulation, mining method determination, and maximum section charge determination;

[0010] (6) Stability analysis of the broken ore body mining south of Line 4: numerical model construction and simulation conditions, calculation cloud map analysis, and surface deformation impact analysis.

[0011] Preferably, the structural parameters of the stope are 60m×10m×20m (length×width×height), the thickness of the artificial false roof is 4m, the strength is 5MPa, the strength of the stope filling body is 3MPa, and the maximum section charge is 98Kg.

[0012] Preferably, the mining method is a segmented open pit followed by filling mining method from bottom to top, with segmented rock drilling, segmented ore extraction, and segmented filling.

[0013] The beneficial effects of adopting the above technical solution are:

[0014] Through on-site exploration of the mine and data collection and analysis, we have mastered the mining history and current status of the mine. Through indoor rock mechanics tests, rock quality classification, rock parameter reduction and other means, we have obtained the rock mechanics parameters of the broken ore body and surrounding rock that can be used for numerical simulation analysis. Then we established a three-dimensional mining model of the mine, and used the finite difference method to conduct a stability analysis. By collecting and calculating the stope parameters, we can obtain a more stable mining method and improve safety. DETAILED DESCRIPTION

[0015] Embodiments of the present invention are described in detail below:

[0016] A research method for a crushed ore body mining method comprises the following steps:

[0017] (1) Geological overview of the mining area: The strata, structure and magmatic rock development of the mining area were analyzed. The structural parameters of the stope are 60m×10m×20m (length×width×height), the thickness of the artificial roof is 4m and the strength is 5MPa, the strength of the stope filling is 3MPa, and the maximum section charge is 98Kg.

[0018] (2) Technical conditions for mining south of mine line 4:

[0019] Quaternary loose rocks: including the Upper Pleistocene sub-clay (Q3), Middle and Lower Pleistocene (Q1+2). The Upper Pleistocene sub-clay is widely exposed on the surface, with a thickness of 66.63 to 95.22 m; it has a relatively compact structure, strong viscoplasticity, and good stability; the Lower Pleistocene is composed of 1 to 4 layers of sand, clay, and gravel, with a total thickness of 4.66 to 114.40 m; it is generally loose in structure and has poor stability under water;

[0020] Engineering geological characteristics of the ancient weathering zone: The weathering zone in the ore deposit is layered, with a depth of 133.88 to 273.63m and a thickness of 34.30 to 199.65m. It is divided into strong weathering zone and weak weathering zone from top to bottom; the strong weathering zone is blocky, gravel, and soil-like; RQD (%) 2.3 to 49.21, with an average of 19.45; the weak weathering zone is 3.5 to 136.16m thick, RQD (%) 28.07 to 77.12, with an average of 49.0; the mechanical strength and integrity of different mineral rocks in the ancient weathering zone vary greatly. The secondary oxidation ore zone is mainly quartz pseudo-image hematite, quartz magnetite iron ore, etc., with strong weathering resistance, relatively complete core, strong mechanical strength, and better integrity and stability than the surrounding rock;

[0021] Ore body roof: The geological report shows that the mining area is mainly composed of biotite plagioclase gneiss, hornblende biotite plagioclase gneiss, plagioclase biotite schist and ferroamphiboly schist. The core is relatively complete, mostly in the form of short columns of 10 to 20 cm and long columns of > 20 cm, and partially broken; RQD (%) is 75.1 to 99.80, with an average of 89.16, the rock quality grade is "good", the rock mass quality index (M) is 0.19 (medium), and the rock mass integrity and stability are good; it was found in production that the surrounding rock of the ore body in the southern area of ​​the mine is relatively broken, and the rock mass integrity is poor, which seriously affects the stability of the stope and the mining accuracy. The safety of the project is that the surrounding rock and roof collapse is very likely to occur during the mining process, which is mainly manifested as follows: 1) There is no shaft engineering above the middle section of -170m, but there is roof collapse in some parts of this middle section. Zhouyoufang Iron Mine has taken measures such as anchor spraying to strengthen support for the drilling chambers and other tunnels in this middle section; 2) Due to the broken surrounding rock of the roof in the middle section of -230m, although the drilling chamber adopts a smaller cross-sectional area, the support engineering volume is still large and the cost is high; 3) The roof of the broken zone area in the middle section of -290m collapsed continuously during the mining process, which poses a major safety hazard and seriously threatens the safety production work of the mine;

[0022] Ore-bearing belt: The geological report shows that the lithology of the ore-bearing belt is mainly quartz magnetite, quartz mirror iron ore, and quartz magnetite mirror iron ore. The interlayer and interlayer lithology of the ore body are quartz biotite schist, biotite schist, quartz two-cloud schist, marble, etc. The marble is 20 to 228.95 meters thick, with undeveloped cracks and mostly filled. The mechanical strength of some parts is significantly reduced under the action of groundwater, RQD (%) 75.35 to 99.39, with an average of 86.94. The rock quality grade is "good", and the rock quality index (M) is 0.14 (medium), and the rock mass has good integrity and stability. It was found in production that the ore body in the southern area is relatively broken, which makes it difficult to carry out mining work and causes serious resource losses in the mining area. The main manifestations are: 1) During the rock drilling process in the broken zone area, hole blockage, drill jamming, and hole opening difficulties often occur. It is difficult to drill in some areas, and the mining and cutting engineering has low excavation efficiency; 2) The ore grade in the broken zone area is high, the reserves are large, and the economic value of recovery is high, but the ore recovery rate is low, and the waste of resources is relatively serious;

[0023] Ore body floor: The geological report shows that the lithology of the floor is mainly dolomite marble, the core is intact, and the fissure karst is not developed; RQD is 64-82%, 71% on average, the rock mass quality index (M) is 0.24 (medium), and the rock mass has good integrity and stability; it was found in production that the lithology of the floor is basically consistent with the description in the geological report; according to the geological report, the engineering geological conditions of the deposit are moderately complex; but actual production has proved that the complexity of the engineering geological conditions in the southern area of ​​the mine exceeds the description in the geological report; the engineering geological conditions are complex;

[0024] (3) Current situation survey: survey of buildings (structures) south of the 4# exploration line, surface displacement monitoring data, rock mass structural surface survey, and drilling and coring survey;

[0025] (4) Rock mechanics tests and parameters: rock physical properties test, rock uniaxial compressive strength test, rock uniaxial compression deformation test, rock tensile strength test, rock regular shear strength test, value of structural surface characteristic grade SCR, value of rock mass structure grade SR, determination of GSI classification parameters, Hoek-Brown strength criterion;

[0026] (5) Optimization of single stope structural parameters: stope stability analysis based on rock mass quality classification, stope stability analysis based on numerical simulation, mining method determination, and maximum charge determination; the mining method is a bottom-up mining method with segmented empty-site and subsequent filling, with segmented rock drilling, segmented ore extraction, and segmented filling.

[0027] (6) Stability analysis of the broken ore body mining south of Line 4: numerical model construction and simulation conditions, calculation cloud map analysis, and surface deformation impact analysis

[0028] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A research method for a crushed ore body mining method, characterized in that: The following steps are involved: (1) Geological exploration of mining areas: analysis of the strata, structure, and development of magmatic rocks in the mining areas; (2) Technical conditions for mining south of mine line 4: analysis of engineering geological conditions, hydrogeological conditions, and environmental geological conditions; (3) Current situation survey: survey of buildings (structures) south of exploration line 4#, surface displacement monitoring data, rock mass structural surface survey, and drilling coring survey. (4) Rock mechanics tests and parameters: rock physical properties test, rock uniaxial compressive strength test, rock uniaxial compression deformation test, rock tensile strength test, rock regular shear strength test, SCR value of structural surface characteristic grade, SR value of rock mass structure grade, GSI classification parameter determination, Hoek-Brown strength criterion; (5) Optimization of single stope structural parameters: stope stability analysis based on rock mass quality classification, stope stability analysis based on numerical simulation, mining method determination, and maximum section charge determination; (6) Stability analysis of the broken ore body mining south of Line 4: numerical model construction and simulation conditions, calculation cloud map analysis, and surface deformation impact analysis.

2. The research method of a broken ore body mining method according to claim 1, characterized in that: The structural parameters of the mining area are 60m×10m×20m (length×width×height), the thickness of the artificial false roof is 4m, the strength is 5MPa, the strength of the mining area filling body is 3MPa, and the maximum section charge is 98Kg.

3. The research method of a broken ore body mining method according to claim 1, characterized in that: The mining method is the segmented open-pit and subsequent filling mining method, with mining from bottom to top, segmented rock drilling, segmented ore extraction, and segmented filling.