High-dipping thin ore body mining method suitable for broken surrounding rock conditions

Abstract

The invention discloses a steeply inclined thin ore body mining method suitable for broken surrounding rock conditions. The method comprises the following steps that S1, engineering geological condition investigation is conducted on an ore body and surrounding rock of the ore body, and stope structure parameters are determined; s2, the ore body is divided into chambers and pillars in the trend according to the length of a stope, and continuous stoping is conducted in two steps; s3, a stope preparation cutting project is constructed in the stope; s4, arranging a slope ramp at the middle position of the ore body close to the ore body, constructing a connection roadway to the other side of the ore body from the slope ramp to the ore body, then constructing stoping access roads from the side, close to the side with good surrounding rock stability, of the vertical connection roadway to the two sides, and performing stoping filling step by step; s5, filling is carried out after the first layer is stoped, stoping of a second layer is carried out after filling is finished and design strength is reached, and circulation is carried out until stoping of the stope is finished; through the arrangement of the spiral slope ramp and the layered platforms, the distance between the slope ramp and the stope is reduced, the work amount of the connection roadway is greatly reduced, meanwhile, each layered platform is responsible for one layer, the gradient of the connection roadway is reduced, and ore transportation and equipment operation are facilitated; and meanwhile, the problems that when the steeply inclined thin ore body under the broken surrounding rock condition is exploited in an upward horizontal layered mode, the broken surrounding rock spans, even an ore body top plate cracks, and the safety of stoping operation of personnel under the cracked top plate is poor are solved, and the method has the advantages of being high in safety, efficiency and mechanization rate and the like.

Description

Technical Field

[0001] The invention relates to the technical field of underground mining, in particular to a steeply inclined thin ore body mining method suitable for broken surrounding rock conditions. Background Art

[0002] Steeply inclined thin ore bodies refer to ore bodies with an inclination angle greater than 55° and an ore body thickness less than 5m. They are commonly found in lead-zinc, gold, tungsten and other deposits. The upward horizontal layered filling mining method is often used to mine such ore bodies. When mining using the upward horizontal layered filling mining method, it is generally arranged along the direction of the ore body, and the length of the stope is about 40.0 to 60.0m. Especially when mining some independent ore bodies, only one stope is often arranged; the mining process is two mining and one filling, and the empty roof height is generally 6.0 to 8.0m. If the above mining method is used in the condition of broken surrounding rock of the ore body, due to the large exposed area of ​​the side wall of the stope, large-scale cross-bursting often occurs, and even causes the roof to crack, causing great safety hazards. Summary of the invention

[0003] In order to reduce the space required for construction, reduce the exposed area of ​​the side walls of the mining area, and improve the safety of operations, the present application provides a steeply inclined thin ore body mining method suitable for broken surrounding rock conditions.

[0004] The present application provides a steeply inclined thin ore body mining method suitable for broken surrounding rock conditions, which adopts the following technical solutions:

[0005] A steeply inclined thin ore body mining method suitable for broken surrounding rock conditions comprises the following steps:

[0006] S1. Conduct engineering geological condition survey on the ore body and its surrounding rock to determine the stope structure parameters;

[0007] S2, dividing the ore body into chambers and pillars along the strike according to the length of the stope, and continuous mining in two steps;

[0008] S3. Carry out the mining and cutting works in the mining field;

[0009] S4. Arrange a ramp at a certain distance from the middle of the ore body, construct a connecting tunnel from the ramp to the other side of the ore body, and then construct a mining access to both sides from the vertical connecting tunnel close to the side with better surrounding rock stability, and carry out mining and filling in steps;

[0010] S5. After the first layer is mined, backfilling is carried out. After the filling is completed and the design strength is reached, the second layer is mined, and the cycle continues until the mining of the stope is completed.

[0011] Optionally, in step S1, it is necessary to perform rock mass quality classification and stability evaluation on the ore body, and then further determine the stope structure parameters according to the Mathews graphical method and numerical simulation software.

[0012] Optionally, in step S2, the length of the stope in step one is consistent with that of the stope in step two, the stope width is the thickness of the ore body, and the stope layer height is 3.0-4.0 m.

[0013] Optionally, the mining and cutting works in step S3 include: ore chute, waste rock chute and filling return air shaft.

[0014] Optionally, in step S4, the ramp is a spiral ramp, a layered platform is formed at each layer height of the ramp, and a connecting tunnel is constructed from each layered platform of the ramp to the other side of the ore body; each layered platform is connected to a different layer.

[0015] Optionally, during the mining process of step S4, if the thickness of the ore body is less than the width of two access roads, after one access road is constructed, the remaining ore bodies are mined in the form of expansion and brushing.

[0016] Optionally, during the mining process of step S4, if the thickness of the ore body reaches more than 2 access widths, mining is carried out through a vertical access after one access is constructed, and permanent point columns are left to support the mining area.

[0017] In summary, this application includes the following beneficial technical effects:

[0018] 1. The present application reduces the distance between the ramp and the stope by setting up a spiral ramp and a layered platform, greatly reducing the engineering workload of the connecting tunnel. At the same time, each layered platform is responsible for one layer, which reduces the slope of the connecting tunnel and facilitates ore transportation and equipment operation.

[0019] 2. First, make a professional estimate and analysis of the ore body, and then divide the length of the mining area. The second step is to first mine an approach, then mine a vertical approach, and then make this approach into a permanent concrete point column to control the exposure area of ​​the mining area roof and side walls, avoid the occurrence of cross-over of broken surrounding rock and even cracks in the ore body roof, and ensure the safety of personnel operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a top view of a typical mining plan where the thickness of the ore body is only 1 to 2 access widths;

[0021] Figure 2 for Figure 1 AA section diagram in;

[0022] Figure 3 for Figure 1 BB cross-section diagram in FIG.

[0023] Figure 4 It is a top view of a typical mining plan when the thickness of the ore body reaches more than 2 access widths;

[0024] Figure 5 for Figure 4 Schematic diagram of CC cross section in ;

[0025] Figure 6 for Figure 4 DD cross-section diagram in ;

[0026] Description of reference numerals:

[0027] 1. Ramp; 2. Ore chute; 3. Waste rock chute; 4. Connecting tunnel; 5. Backfill retaining wall; 6- Mining access; 7. First layer; 8. Ore body; 9. Backfill air shaft; 10. Second layer; 11. Drilling rig; 12. Blast hole; 13. Mine pillar. DETAILED DESCRIPTION

[0028] The following is combined with Figure 1-6 This application is described in further detail.

[0029] Embodiment 1;

[0030] refer to Figures 1 to 3 The present application discloses a method for mining a steeply inclined thin ore body suitable for broken surrounding rock conditions, which comprises the following steps:

[0031] Step S1: The rock mass quality and stability of the ore body and its upper and lower wall surrounding rocks are graded and evaluated, and then the stope structure parameters are obtained according to the Mathews graphical method and numerical simulation software; here, the upper wall surrounding rock (quartz porphyry) of the ore body is III-IV rock mass, the lower wall surrounding rock (Shidengzi limestone) is II-III rock mass, and the upper wall exposure area is 100m 3 For example, in order to control the stability of the hanging wall, the stope structure parameters are set to 3.0×30.0m.

[0032] Step S2: Taking the ore body with a length of 60.0m as an example, the ore body is divided into two stopes along the strike, and continuous mining is carried out in two steps. The length of the stope in step one is the same as that in step two, both of which are 30.0m. The stope width is the thickness of the ore body, and the stope layer height is 3.0m.

[0033] Step S3, constructing the mining and cutting project in the mining field, including the ore chute 2, the waste rock chute 3 and the filling return air shaft.

[0034] Step S4, first arrange a spiral ramp 1 at a distance of 6.0m from the ore body on the side with better surrounding rock stability in the middle of the ore body, and make a layered platform (3m, 6m, 9m ore body, etc.) every 3.0m on the ramp 1, and construct a connecting tunnel 4 from each layered platform of the ramp 1 to the other side of the ore body, and then construct a 2.6×3.0m mining approach to both sides of the vertical connecting tunnel 4 close to the side with better surrounding rock stability; in this embodiment of the present application, if the thickness of the ore body is less than the width of two approaches, the remaining ore bodies are mined in the form of expansion and brushing after one approach is constructed.

[0035] Step S5, in the mining, the mining is carried out in the form of mining one and filling one, that is, filling is carried out after the first layer is mined, and a filling retaining wall 5 is set in the connecting tunnel 4 during the filling process. After the filling is completed and the design strength is reached, the second layer is mined, and the cycle is continued until the mining of the stope is completed.

[0036] Embodiment 2;

[0037] refer to Figures 4 to 6 The difference between this embodiment and embodiment 1 is that the thickness of the ore body is greater than the width of the two access roads. In step S4, after one access road is constructed, the vertical access road is mined. First, a vertical access road is mined at intervals of 10m. Secondly, the mined vertical access road is filled with high-strength concrete to make permanent point columns, and then other vertical access roads are mined. Finally, after the stratified mining is completed, the road is filled according to the design requirements.

[0038] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for mining steeply inclined thin ore bodies suitable for broken surrounding rock conditions, characterized in that The steps include: S1. Conduct engineering geological condition survey on the ore body and its surrounding rock to determine the stope structure parameters; S2, dividing the ore body into chambers and pillars along the strike according to the length of the stope, and continuous mining in two steps; S3. Carry out the mining and cutting works in the mining field; S4. Arrange a ramp at a certain distance from the middle of the ore body, construct a connecting tunnel from the ramp to the other side of the ore body, and then construct a mining access to both sides from the vertical connecting tunnel close to the side with better surrounding rock stability, and carry out mining and filling in steps; S5. After the first layer is mined, backfilling is carried out. After the filling is completed and the design strength is reached, the second layer is mined, and the cycle continues until the mining of the stope is completed.

2. A steeply inclined thin ore body mining method suitable for broken surrounding rock conditions according to claim 1, characterized in that: In step S1, the rock mass quality and stability evaluation of the ore body are required, and then the stope structure parameters are further determined according to the Mathews graphical method and numerical simulation software.

3. The method for mining a steeply inclined thin ore body suitable for broken surrounding rock conditions according to claim 1, characterized in that: In step S2, the length of the stope in step one is consistent with that of the stope in step two, the stope width is the thickness of the ore body, and the stope layer height is 3.0-4.0 m.

4. The method for mining a steeply inclined thin ore body suitable for broken surrounding rock conditions according to claim 1, characterized in that: The mining and cutting project in step S3 includes: ore chute, waste rock chute and filling return air shaft.

5. The method for mining a steeply inclined thin ore body suitable for broken surrounding rock conditions according to claim 1, characterized in that: In step S4, the ramp is a spiral ramp, and a layered platform is formed at each layer height of the ramp. A connecting tunnel is constructed from each layered platform of the ramp to the other side of the ore body; each layered platform is connected to a different layer.

6. A steeply inclined thin ore body mining method suitable for broken surrounding rock conditions according to claim 5, characterized in that: During the mining process of step S4, if the thickness of the ore body is less than the width of two access roads, the remaining ore bodies are mined in the form of expansion and brushing after one access road is constructed.

7. A steeply inclined thin ore body mining method suitable for broken surrounding rock conditions according to claim 6, characterized in that: During the mining process in step S4, if the thickness of the ore body reaches more than 2 access widths, mining is carried out through a vertical access after one access is constructed, and permanent point columns are left to support the mining area.

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