A method for mining fractured ore and rock in steeply dipping thin veins

Abstract

This invention discloses a mining method applicable to steeply dipping thin veins and fractured ore rocks. Vertically, the ore body is divided into multiple mining stages, with each stage being mined sequentially from top to bottom. Vertically, the ore body is divided into multiple mining units, with different units arranged alternately. Within each stage, the first unit is further divided into multiple mining layers from top to bottom. Each layer is mined based on the backfilling of the upper layer, with the upper backfill providing a false bottom protection structure. Within the stage, the second unit is mined after the first unit along both sides of the strike within that stage is mined. This is achieved by constructing a series of blasting holes parallel to the cutting groove, using the cutting groove formed after the blasting of the cut-out as the free face. This invention optimizes the mining method of the first and second units within each stage by dividing the ore body into multiple mining stages and alternating the arrangement of the first and second units, thus achieving safe mining of steeply dipping thin veins and fractured ore rocks.

Description

Technical Field

[0001] This invention belongs to the field of mining technology. It relates to a mining method suitable for fractured ore rocks in steeply dipping, thin veins. Background Technology

[0002] Unstable, fractured ore bodies with a dip angle greater than 70°, a thickness of 3-8m, and an exposed area of ​​less than 50m² allowed without support from the ore body and the surrounding rocks of the hanging wall and footwall, and with well-developed joints and fissures, are called steeply dipping thin vein fractured ore bodies.

[0003] Steeply dipping, thin veins with fractured ore are prone to collapse and caving after exposure. When using traditional upward mining methods, timely support of the goaf roof and walls is required after the ore body is exposed in the stope. This involves complex processes, high mining costs, and low production efficiency. In practice, insufficient support strength for the fractured ore body often leads to collapse and caving of the goaf roof and walls, resulting in significant ore body loss and dilution, and high safety risks. When using downward mining methods, because both the ore body and the hanging wall and footwall are unstable, the supporting rock at the contact point between the filling false roof and the hanging wall and footwall is insufficient. In practice, collapse of the fractured footwall and footwall often leads to instability of the filling false roof, resulting in its collapse and making it difficult to guarantee mining safety. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a mining method suitable for steeply inclined thin veins and fractured ore rocks, so as to overcome the technical shortcomings of existing mining technology in the mining of ore bodies under the condition of steeply inclined thin veins and fractured ore rocks, and effectively solve the safety problem of ore body mining under the condition of steeply inclined thin veins and fractured ore rocks.

[0005] The technical solution of this invention is as follows:

[0006] A method for mining fractured ore and rock in steeply dipping thin veins, comprising the following steps:

[0007] Step 1: Divide the ore body vertically into multiple mining stages. Mining different mining stages in a top-to-bottom order, mining the first mining stage first and then the second mining stage.

[0008] Step 2: Divide the ore body into multiple mining units along the strike, with different mining units arranged alternately. The first unit is the second unit on both sides of the strike, and the second unit is the first unit on both sides of the strike; mine the first unit first, then mine the second unit.

[0009] Step 3: The first unit between stages adopts a downward approach for mining. The ore body of the first unit is divided into multiple mining layers. The layers are mined sequentially from top to bottom. The lower layer is mined on the basis of the filling of the corresponding upper layer. The mining range of the upper layer along the ore body extends beyond the mining range of the lower layer along the ore body on both sides. The mining of the lower layer is within the protection range of the false top filled by the upper layer.

[0010] Step 4: In the second unit between stages, medium-deep hole stoping is adopted. The ore body to be mined in the second unit is in a "convex" shape vertically. The length of the upper ore body along the strike is less than that of the lower ore body along the strike. The boundary of the ore body of the second unit along the strike is the boundary of the filling false roof of the first unit along the strike.

[0011] Preferably, the stoping method of the first unit in Step 3 is as follows:

[0012] Step 3-1: Construct a cross-cut from the out-of-reef sublevel drift arranged in the footwall of the ore body to the hanging wall of the ore body, and then construct an in-reef cut-off drift along the strike of the ore body to the boundary of the ore body along the strike of the level. The in-reef cut-off drift is arranged in the middle of the ore body of the level.

[0013] Step 3-2: After the construction of the in-reef cut-off drift is completed, using the in-reef cut-off drift as the free face, blast and stop the ore bodies in the hanging wall and footwall of the cut-off drift. The ore produced by blasting is transported out through the cross-cut.

[0014] Step 3-3: After the stoping of the level is completed, backfill with a high-strength filling body with a strength not lower than 6 MPa and a cement-sand ratio not lower than 1:5 through the cross-cut until reaching the roof, serving as the filling false roof for the stoping of the lower level.

[0015] Step 3-4: After the filling of the upper level is completed, repeat Steps 3-1, 3-2, and 3-3 to complete the stoping of the lower level. The filling false roof of the upper level provides a safety protection structure for the stoping of the lower level.

[0016] Step 3-5: Repeat Steps 3-1, 3-2, 3-3, and 3-4 to complete the stoping of the first unit.

[0017] Preferably, the stoping method of the second unit in Step 4 is as follows:

[0018] Step 4-1: On the basis that the stoping and filling up to the roof are completed on both sides along the strike of the first unit, construct a lower connecting drift of the cut-through raise from the out-of-reef sublevel drift arranged in the footwall of the ore body to the hanging wall of the ore body in the lower part of the second unit, and construct an upper connecting drift of the cut-through raise from the out-of-reef sublevel drift arranged in the footwall of the ore body to the hanging wall of the ore body in the upper part of the second unit. Connect the cut-through raise with the upper connecting drift of the cut-through raise from the lower connecting drift of the cut-through raise.

[0019] Step 4-2: In the lower part of the second unit, construct a medium-deep hole stope connecting drift from the out-of-reef sublevel drift arranged in the footwall of the ore body to exceed the hanging wall of the ore body. The end of the medium-deep hole stope connecting drift is located in the wall rock of the hanging wall of the ore body. The medium-deep hole stope connecting drift is arranged under the filling false roof of the last level of the first unit in the stage. Construct a medium-deep hole drilling and ore-drawing drift along the in-reef of the ore body along the strike to connect with the lower connecting drift of the cut-through raise. The medium-deep hole drilling and ore-drawing drift is arranged in the middle of the ore body.

[0020] Step 4-3: After the cut well is formed, construct medium-deep hole blasting holes parallel to the cut well through the connecting road at the bottom of the cut well. Fill the medium-deep hole blasting holes with explosives to form a medium-deep hole cutting groove with the cut well as the free surface.

[0021] Step 4-4: After the medium-deep hole cutting groove is formed, medium-deep hole blasting holes parallel to the cutting groove are constructed through medium-deep hole drilling and mining roadway construction. The bottom of the medium-deep hole blasting hole is 60cm below the false bottom of the first unit filling body on both sides of the strike. The depth of different rows of medium-deep hole blasting holes gradually decreases from the cutting raise to the two wings of the strike. With the medium-deep hole cutting groove as the free surface, the ore body on both sides of the ore body along the strike is mined by blasting in stages by filling the medium-deep hole blasting holes with explosives. The ore produced by blasting is transported out through the medium-deep hole stope connecting roadway and the lower connecting roadway of the cutting raise.

[0022] Steps 4-5: After the second unit mining is completed, the upper connecting road of the cut-up shaft is filled in two steps using filling bodies of different strengths. The lower part of the mined-out area of ​​the second unit is filled with a high-strength filling body with a strength of not less than 6MPa and a ash-sand ratio of not less than 1:5, and the upper part is filled with a conventional-strength filling body with a strength of not less than 4MPa and a ash-sand ratio of not less than 1:8. The high-strength filling body and the conventional-strength filling body together form a false roof of the filling body. The upper conventional-strength filling body fills up to the top plate of the upper connecting road of the cut-up shaft. The filling height of the high-strength filling body is not less than the height of the four layers of the first unit.

[0023] Preferably, when the first unit is mined in a top-to-bottom order, the lower layer is mined on the basis of the filling and support of the upper layer. The range of the false top of the upper layer exceeds the mining range of the lower layer along the strike. The two sides of the mining of the lower layer along the strike do not exceed the two sides of the false top of the upper layer along the strike of the ore body. During the mining of the lower layer, the part below the portion of the false top of the upper layer that exceeds the mining range of the lower layer is the ore body of the second unit to be mined. The ore body of the second unit to be mined reliably supports the stability of the filling and support of the upper layer. The reliable filling and support of the upper layer ensures safety during the mining of the lower layer.

[0024] Preferably, the medium-deep hole stope connecting passage of the second unit is arranged below the last layer of the false top filled in the first unit in this stage. The end of the medium-deep hole stope connecting passage is located in the surrounding rock of the hanging wall of the ore body. After the goaf of the second unit is filled, the false top of the lower filling body of the second unit enters the range of the first unit along the strike. The false tops of the lower filling bodies of adjacent second units are connected along the strike, and the false top of the medium-deep hole stope connecting passage extends into the waste rock in the hanging wall of the ore body, jointly protecting the safe mining of the first and second units in the lower mining stage. The false top of the medium-deep hole stope connecting passage extends perpendicular to the strike of the ore body into the surrounding rock of the hanging wall and footwall of the ore body. The surrounding rock of the hanging wall and footwall of the ore body reliably supports the false top of the second unit, ensuring the overall stability of the false top of the second unit.

[0025] Preferably, in the upper mining stage, the false top of the second unit filling body extends along the strike of the ore body to the middle of the first unit on both sides. The false top of the second unit filling body supports the false tops of each layer of the first unit filling body, ensuring the overall stability of the false tops of each layer of the first unit filling body. The false tops of the two adjacent second units filling bodies in the upper mining stage provide a stable false top structure for the mining of the first unit in the lower mining stage, ensuring the safety of the mining of the first unit in the lower mining stage.

[0026] Preferably, different mining units in the same mining stage can be mined simultaneously. The first unit in the lower mining stage can be safely mined under the protection of the second unit in the upper stage with a false roof. The same mining units in different mining stages that do not overlap along the ore body strike can be mined simultaneously.

[0027] The steeply dipping thin vein fractured ore refers to ore with a dip angle greater than 70°, a vein thickness of 3-8m, and an exposed area of ​​less than 50m² allowed under unsupported conditions of the ore body and the surrounding rocks of the hanging wall and footwall.

[0028] Compared to existing technologies, this invention has the following advantages: By dividing the mining process into multiple stages, with alternating first and second units within each stage, and by optimizing the mining methods for the first and second units in each stage, this invention achieves safe mining of fractured ore and rock in steeply inclined thin veins. Specifically:

[0029] (1) When the first unit is mined in the order of top to bottom, the lower layer is mined on the basis of the filling and top of the upper layer. The range of the false top of the upper layer exceeds the mining range of the lower layer along the strike. The mining of the lower layer does not exceed the boundary of the false top of the upper layer along the strike of the ore body. During the mining of the lower layer, it exceeds the boundary of the lower layer along the strike. The mining of the second unit ore body can reliably support the filling and top of the upper layer, which can ensure safety during the mining of the lower layer.

[0030] (2) The deep-hole stope connecting roadway of the second unit is located in the middle of the bottom of the first unit. The upper part of the deep-hole stope connecting roadway is the last layer of filling false top of the second unit stage. The end of the deep-hole stope connecting roadway is located in the wall rock of the ore body. After the goaf of the second unit is filled, the lower filling false top of the second unit enters the range of the first unit along the strike. The lower filling false tops of the adjacent second units are connected along the strike. The deep-hole stope connecting roadway filling false tops extend to the waste rock in the wall rock of the ore body to jointly protect the safe mining of the lower mining stage. The deep-hole stope connecting roadway filling false tops extend vertically to the wall rock of the ore body. The wall rock of the wall rock of the ore body reliably supports the filling false tops of the second unit, which can ensure the overall stability of the filling false tops of the second unit.

[0031] (3) The false top of the second unit filling body in the upper mining stage extends along the ore body to the middle of the first unit on both sides. The false tops of the two adjacent second units filling bodies in the upper mining stage provide a stable false top structure for the mining of the first unit in the lower mining stage, which can ensure the safety of the mining of the first unit in the lower mining stage.

[0032] (4) Different mining units in the same mining stage can be mined simultaneously. The first unit in the lower mining stage can be safely mined under the protection of the false roof filled by the second unit in the upper stage. The same mining units in different mining stages that do not overlap along the ore body can be mined simultaneously. Attached Figure Description

[0033] Figure 1 This is a longitudinal projection diagram of the method of the present invention during implementation.

[0034] Figure 2 This is a top-view projection of the method of the present invention during implementation. Figure 2 At the same time as Figure 1 BB view.

[0035] Figure 3 This is a side view of the method of the present invention during implementation. Figure 3 At the same time as Figure 1 AA view.

[0036] In the diagram, 1. Layered connecting roadway; 2. First unit layered filling false roof; 3. Upper connecting roadway of the cutting raise; 4. Lower connecting roadway of the cutting raise; 5. Medium-deep hole stope connecting roadway; 6. Blasted ore; 7. Medium-deep hole blasting hole; 8. Second unit ore body to be mined; 9. First unit ore body to be mined; 10. External segmented roadway; 11. First unit internal cutting roadway; 12. Cutting raise; 13. Medium-deep hole rock drilling and ore extraction roadway; 14. Cutting groove; 15. Second unit filling false roof. Detailed Implementation

[0037] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0038] like Figure 1 , Figure 2 and Figure 3 This invention discloses a mining method applicable to steeply dipping thin veins and fractured ore rocks, the core mining steps of which are:

[0039] The ore body is divided into multiple mining stages along the vertical direction. The different mining stages are mined in a top-to-bottom order, with the first mining stage mined first and the second mining stage mined later.

[0040] The ore body is divided into multiple mining units along the strike, with different mining units arranged alternately. The first unit is the second unit on both sides of the strike, and the second unit is the first unit on both sides of the strike. The first unit is mined first, followed by the second unit.

[0041] In the first unit between stages, downward drifts are used for stoping. The ore body of the first unit is divided into multiple stoping slices, and the slices are stoped in sequence from top to bottom. The lower slice is stoped based on the filling of the corresponding upper slice; the upper slice exceeds the lower slice on both sides along the strike of the ore body, and the stoping scope of the lower slice is smaller than the filling false roof scope of the upper slice;

[0042] In the second unit between stages, medium-deep holes are used for stoping. The ore body to be stoped in the second unit is in a "convex" shape vertically. The strike length of the upper part of the ore body along the vertical direction is smaller than that of the lower part. The strike boundary of the ore body in the second unit is the strike boundary of the filling false roof of the first unit;

[0043] In the same mining stage, different mining units can be stoped synchronously. The first unit in the lower mining stage is safely stoped under the protection of the filling false roof 15 of the second unit in the upper stage. The same mining units with non-overlapping strike scopes in different mining stages can be stoped synchronously.

[0044] Such as Figure 1 、 Figure 2 and Figure 3 , an embodiment of a mining method suitable for broken ore and rock in steeply inclined thin ore veins. The stoping steps of the first unit in the same mining stage are as follows:

[0045] Step 1: Construct the slice connection drift 1 from the sectional drift 10 outside the hanging wall of the ore body to the hanging wall of the ore body, and construct the first unit in-vein cutting drift 11 along the strike of the ore body to the strike boundary of the ore body in the slice. The first unit in-vein cutting drift 11 is arranged in the middle of the slice ore body. After the construction of the first unit in-vein cutting drift 11 is completed, the ore bodies on both the upper and lower walls of the first unit in-vein cutting drift 11 are stoped with the first unit in-vein cutting drift 11 as the blasting free face. The blasted ore 6 is transported out through the slice connection drift 1;

[0046] Step 2: After the slice stoping is completed, fill the mined-out area with a high-strength filling body with a strength not lower than 6 MPa and a cement-sand ratio not lower than 1:5 through the slice connection drift 1 until it reaches the roof, forming the first unit slice filling false roof 2;

[0047] Step 3: Repeat Step 1 and Step 2 to complete the stoping and filling of each slice of the ore body 9 to be mined in the lower first unit. The lower slices are safely stoped under the protection of the filling false roof 2 of the upper slices. The scope of the upper slice filling false roof 2 exceeds the stoping scope of the lower slice to be mined along the strike. The strike boundaries on both sides of the lower slice stoping do not exceed the strike boundaries on both sides of the upper slice filling false roof along the ore body. During the stoping of the lower slice, the part of the upper slice filling false roof that exceeds the stoping scope of the lower slice is the ore body of the second unit to be mined below;

[0048] Step 4: Repeat Step 1, Step 2, and Step 3 to complete the stoping of the first unit in this mining stage.

[0049] The stoping steps of the second unit in the same mining stage are as follows:

[0050] Step 1: After the first unit of the second phase of mining is completed along the strike of the ore body, the upper connecting roadway 3 and the lower connecting roadway 4 of the cutting raise will be constructed from different external segment roadways 10 to the hanging wall of the ore body. The cutting raise 12 will be constructed to connect with the upper connecting roadway 3 of the cutting raise through the lower connecting roadway 4.

[0051] Step 2: The deep-hole mining access road 5 is constructed from the external segment roadway 10 to the wall of the ore body. The deep-hole mining access road 5 is located below the last layer of the false roof filling in the first unit of this stage. The end of the deep-hole mining access road 5 is located in the wall of the ore body. The deep-hole drilling and mining access road 13 is constructed along the ore body strike from the deep-hole mining access road 5 and connects with the lower access road 4 of the cutting riser. The deep-hole drilling and mining access road 13 is located in the middle of the ore body.

[0052] Step 3: After the cut well 12 is formed, a medium-deep hole 7 parallel to the cut well 12 is constructed through the connecting passage 4 at the bottom of the cut well. Explosives are filled into the medium-deep hole 7 and the cut well 12 is used as the free surface for blasting to form the cutting groove 14.

[0053] Step 4: Construct medium-deep blasting holes 7 parallel to the cutting groove 14 through medium-deep hole drilling and mining roadway 13. The bottom of the medium-deep blasting holes 7 is 60cm below the false bottom of the first unit filling body on both sides of the strike. The depth of different rows of medium-deep blasting holes 7 gradually decreases from the cutting raise to the two wings of the strike. Explosives are filled in the medium-deep blasting holes 7 and the second unit of ore body 8 is blasted and collapsed with the cutting groove 14 as the free surface. The blasted ore 6 is transported out through the lower connecting roadway 4 of the cutting raise and the medium-deep hole stope connecting roadway 5.

[0054] Step 5: After the medium-deep hole mining is completed, the goaf is filled in two steps by cutting the upper connecting roadway 3 of the raised shaft. The lower part uses a high-strength filling body with a strength of not less than 6MPa and a lime-sand ratio of not less than 1:5. The filling height of the high-strength filling body is not less than the height of the four layers of the first unit. The upper part uses a conventional strength filling body with a strength of not less than 4MPa and a lime-sand ratio of not less than 1:8. The goaf is filled until the upper connecting roadway 3 of the raised shaft is connected to the roof, forming the second unit filling false roof 15. The second unit filling false roof 15 enters the range of the first unit along the strike. The adjacent second unit filling false roof 15 are connected along the strike, and the connection extends to the filling false roof in the medium-deep hole stope connecting roadway 5 in the waste rock of the hanging wall of the ore body.

[0055] Step 6: After the second unit of this mining stage is completed and backfilled, the first unit of the next mining stage is ready for mining.

[0056] Different mining units in the same mining stage can be mined simultaneously. The first unit in the lower mining stage can be safely mined under the protection of the second unit in the upper stage with a false roof. The same mining units in different mining stages that do not overlap along the ore body can be mined simultaneously.

Claims

1. A method for mining fractured ore and rock in steeply dipping thin veins, characterized in that... The steps are as follows: Step 1: Vertically divide the ore body into multiple mining stages. The different mining stages are mined in sequence from top to bottom. First, mine the first mining stage, and then mine the second mining stage; Step 2: Horizontally divide the ore body into multiple mining units. The different mining units are arranged alternately. The first unit has the second unit on both sides along the strike. The second unit has the first unit on both sides along the strike. First, mine the first unit, and then mine the second unit; Step 3: For the first unit between stages, use downward drifts for mining. The ore body of the first unit is divided into multiple mining slices. The slices are mined in sequence from top to bottom. The lower slice is mined on the basis of the filling of the corresponding upper slice. The mining range of the upper slice along the strike of the ore body exceeds that of the lower slice on both sides. The mining of the lower slice is within the protection range of the filling false roof of the upper slice; Step 4: For the second unit between stages, use medium-deep holes for mining. The ore body to be mined in the second unit is "convex" in shape vertically. The length of the upper part of the ore body along the strike is less than that of the lower part. The boundary of the ore body of the second unit along the strike is the boundary of the filling false roof of the first unit along the strike; The mining method of the second unit in Step 4 is as follows: Step 4-1: On the basis that the mining of the first unit on both sides along the strike is completed and filled to the top, construct a lower connecting roadway of the cut raise from the sectional roadway outside the footwall of the ore body to the hanging wall of the ore body for the lower part of the second unit, and construct an upper connecting roadway of the cut raise from the sectional roadway outside the footwall of the ore body to the hanging wall of the ore body for the upper part of the second unit. Connect the lower connecting roadway of the cut raise and the upper connecting roadway of the cut raise through the cut raise; Step 4-2: Construct a medium-deep hole stope connecting roadway from the sectional roadway outside the footwall of the ore body to exceed the hanging wall of the ore body for the lower part of the second unit. The end of the medium-deep hole stope connecting roadway is located in the surrounding rock of the hanging wall of the ore body. The medium-deep hole stope connecting roadway is arranged under the filling false roof of the last slice of the first unit in the stage. Construct a medium-deep hole drilling and ore-drawing roadway parallel to the ore body strike in the ore vein from the medium-deep hole stope connecting roadway to connect with the lower connecting roadway of the cut raise. The medium-deep hole drilling and ore-drawing roadway is arranged in the middle of the ore body; Step 4-3: After the cut raise is formed, construct medium-deep hole blasting holes parallel to the cut raise at the footwall of the cut raise through the lower connecting roadway of the cut raise. Form a medium-deep hole cut by loading explosives in the medium-deep hole blasting holes with the cut raise as the free face; Step 4-4: After the medium-deep hole cut is formed, construct medium-deep hole blasting holes parallel to the cut through the medium-deep hole drilling and ore-drawing roadway. The bottom distance of the medium-deep hole blasting holes is 60 cm below the filling false roof of the first unit on both sides along the strike. The depths of the medium-deep hole blasting holes in different rows gradually decrease from the cut raise to the two wings along the strike. With the medium-deep hole cut as the free face, mine the ore bodies on both sides along the strike of the medium-deep hole cut by loading explosives in the medium-deep hole blasting holes and blasting in batches. The ore produced by the blasting is transported out through the medium-deep hole stope connecting roadway and the lower connecting roadway of the cut raise; Steps 4-5: After the second unit mining is completed, the upper connecting road of the cut-up shaft is filled in two steps using filling bodies of different strengths. The lower part of the mined-out area of ​​the second unit is filled with a high-strength filling body with a strength of not less than 6MPa and a ash-sand ratio of not less than 1:5, and the upper part is filled with a conventional-strength filling body with a strength of not less than 4MPa and a ash-sand ratio of not less than 1:

8. The high-strength filling body and the conventional-strength filling body together form a false roof of the filling body. The upper conventional-strength filling body fills up to the top plate of the upper connecting road of the cut-up shaft. The filling height of the high-strength filling body is not less than the height of the four layers of the first unit.

2. The mining method for fractured ore and rock in steeply dipping thin veins as described in claim 1, characterized in that... The data recovery method for the first unit in step 3 is as follows: Step 3-1: Construct a layered connecting roadway from the segmented roadway located on the lower plate of the ore body to the upper plate of the ore body, and construct an intra-vein cutting roadway along the strike of the ore body to the boundary of the layered ore body along the strike. The intra-vein cutting roadway is arranged in the middle of the layered ore body. Step 3-2: After the construction of the vein cutting tunnel is completed, the vein cutting tunnel is used as the free face to blast and mine the upper and lower hanging walls of the cutting tunnel. The ore produced by the blasting is transported out through the layered connecting tunnel. Step 3-3: After the layered mining is completed, the layered connecting tunnel is filled with high-strength filling material with a strength of not less than 6MPa and a cement-sand ratio of not less than 1:5 until the top is reached, which will serve as the false top for filling during the next layered mining. Steps 3-4: After the upper layer filling is completed, repeat steps 3-1, 3-2, and 3-3 to complete the lower layer mining. The upper layer filling false roof provides a safety protection structure for the lower layer mining. Step 3-5: Repeat steps 3-1, 3-2, 3-3, and 3-4 to complete the first unit of data collection.

3. The mining method for fractured ore and rock in steeply dipping thin veins as described in claim 1, characterized in that: When the first unit is mined in a top-to-bottom order, the lower layer is mined on the basis of the filling and support of the upper layer. The range of the false top of the upper layer's filling extends beyond the mining range of the lower layer along the strike. The two sides of the mining range of the lower layer along the strike do not exceed the two sides of the false top of the upper layer's filling along the strike of the ore body. During the mining of the lower layer, the part below the portion of the false top of the upper layer's filling that extends beyond the mining range of the lower layer is the ore body of the second unit to be mined. The ore body of the second unit to be mined reliably supports the stability of the filling and support of the upper layer. The reliable filling and support of the upper layer ensures safety during the mining of the lower layer.

4. The mining method for fractured ore and rock in steeply dipping thin veins as described in claim 1, characterized in that: The medium-deep hole stope connecting roadway described in the second unit mining is located below the last layer of the false top filling in the first unit during this stage. The end of the medium-deep hole stope connecting roadway is located within the hanging wall of the ore body. After the goaf of the second unit mining is filled, the false top filling body of the lower part of the second unit enters the range of the first unit along the strike. The false top filling bodies of the lower parts of the second unit are connected along the strike, and the medium-deep hole stope connecting roadway filling false top extends into the waste rock in the hanging wall of the ore body, jointly protecting the safe mining of the first and second units in the lower mining stage. The medium-deep hole stope connecting roadway filling false top extends perpendicularly to the strike of the ore body into the hanging wall and footwall of the ore body. The hanging wall and footwall of the ore body reliably support the filling false top of the second unit, ensuring the overall stability of the filling false top of the second unit.

5. The mining method for fractured ore and rock in steeply dipping thin veins as described in claim 1, characterized in that: In the upper mining stage, the false roof of the second unit filling body extends along the strike of the ore body to the middle of the first unit on both sides. The false roof of the second unit filling body supports the false roof of each layer of the first unit filling body, ensuring the overall stability of the false roof of each layer of the first unit filling body. The false roofs of the two adjacent second units filling bodies in the upper mining stage provide a stable false roof structure for the mining of the first unit in the lower mining stage, ensuring the safety of the mining of the first unit in the lower mining stage.

6. The mining method for fractured ore and rock in steeply dipping thin veins as described in claim 1, characterized in that: In the same mining stage, different mining units are mined simultaneously. In the lower mining stage, the first unit is safely mined under the protection of the false roof filled by the second unit in the upper stage. In different mining stages, the same mining units along the ore body strike that do not overlap are mined simultaneously.

7. The mining method for fractured ore and rock in steeply dipping thin veins as described in any one of claims 1 to 6, characterized in that: The steeply dipping thin vein fractured ore refers to ore with a dip angle greater than 70°, a vein thickness of 3-8m, and an exposed area of ​​less than 50m² allowed under unsupported conditions of the ore body and the surrounding rocks of the hanging wall and footwall.

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