Method for stoping chambers among subsections of steeply inclined thick ore body

Abstract

The invention relates to a steeply inclined thick ore body inter-section room stoping method which comprises the steps that a stope connection way is constructed from a section roadway to an ore body footwall, a vein roadway is constructed in the direction of the ore body footwall, a room is divided, and the room is continuously divided into a plurality of stoping units; main ore removal roadways, auxiliary ore removal roadways and inclined ore removal roadways are constructed in the middle position of the chamber and the lower sections of the two units on the outer side, pre-control top main roadways, pre-control top auxiliary roadways and pre-control top inclined roadways are constructed in the middle position of the chamber and the upper sections of the two units on the outer side, and the stoping units on the two sides of the main ore removal roadways are symmetrically arranged and are the same in number; and a cutting well is constructed in the middle area of the stoping units on the two sides, blasting stoping is conducted on the hanging wall and the footwall of the ore body from the cutting well, four working faces are formed in total, ore obtained after blasting of the hanging wall ore body is transported through the ore removal main roadway, and ore obtained after blasting of the footwall ore body is transported through the ore removal auxiliary roadway. According to the method, multi-working-face collaborative ore removal and transportation path diversion can be achieved, the stoping efficiency of the chambers is improved, and the stoping period of the chambers is shortened.

Description

Technical Field

[0001] This application relates to the field of mining technology, and in particular to a method for mining stopes in a steeply inclined thick ore body in subdivided sections. Background Technology

[0002] Currently, most underground mines in my country employ either upward or downward approach backfilling mining methods when facing steeply dipping, thick ore bodies. These two methods involve mining in opposite directions. During normal mining operations on thick ore bodies, both methods require constructing multiple approaches along the strike or dip of the ore body, with each approach undergoing a cycle of "mining-extraction-backfilling-maintenance." This process is lengthy, involves significant support work, and is costly. Especially given the rapidly increasing temperatures in deep underground mining today, the high labor intensity for workers necessitates shortening the overall mining cycle to reduce safety hazards. Summary of the Invention

[0003] The purpose of this application is to provide a method for mining stopes in subdivided sections of steeply dipping thick ore bodies, so as to solve or alleviate the problems existing in the above-mentioned prior art.

[0004] To achieve the above objectives, this application provides the following technical solution: This invention provides a method for inter-subdivided stope mining of steeply dipping thick ore bodies, which includes the following steps: Step 1: From the segmented roadway construction stope connecting roadway to the footwall of the ore body, construct the vein roadway along the strike of the footwall of the ore body and divide the stopes into multiple mining units; Step 2: Construct the main ore extraction roadway, auxiliary ore extraction roadway, and inclined ore extraction roadway in the lower section of the middle and outer two units of the stope. Construct the pre-controlled roof main roadway, pre-controlled roof auxiliary roadway, and pre-controlled roof inclined roadway in the upper section of the middle and outer two units of the stope. The mining units on both sides of the main ore extraction roadway are symmetrically arranged and have the same number. Step 3: Construct a cutting shaft in the middle area of ​​the two mining units. Starting from the cutting shaft, blasting and mining are carried out on the hanging wall and footwall of the ore body to form a total of four working faces. The ore after blasting of the hanging wall ore body is transported through the main ore extraction roadway, and the ore after blasting of the footwall ore body is transported through the auxiliary ore extraction roadway.

[0005] In some embodiments, the method for inter-subdivided stope mining of a steeply inclined thick ore body further includes: Fan-shaped blasting holes were arranged on the upper and lower sides of the ore body, while vertical blasting holes were arranged in other areas.

[0006] In some embodiments, the method for inter-subdivided stope mining of a steeply inclined thick ore body further includes: After the mining units on both sides have finished mining, a false bottom material is laid on the bottom plate of the goaf and reinforced with welded bars. Half-face filling and sealing walls are constructed at the junctions of the auxiliary mining roadway and the footwall vein roadway, and the auxiliary mining roadway and the inclined mining roadway, and high-ratio cemented filling material is injected into the goaf to form a false bottom.

[0007] Continue to construct full-height filling and sealing walls at the junctions of the ore extraction auxiliary roadway and the footwall vein roadway, and at the junctions of the ore extraction auxiliary roadway and the ore extraction inclined roadway. The goaf is then rapidly filled by the corresponding pre-controlled top inclined roadway in the upper section.

[0008] In some embodiments, the method for inter-subdivided stope mining of a steeply inclined thick ore body further includes: After the outermost mining unit is filled, mining and filling are carried out gradually from both sides towards the middle mining unit according to steps 2 and 3.

[0009] In some embodiments, the method for inter-subdivided stope mining of a steeply inclined thick ore body further includes: During the process of mining from both sides towards the middle mining unit, mining stops when three or four adjacent mining units in the middle are reached. The ore body of the three or four mining units in the middle is divided into layers from bottom to top to form multiple layered mining areas. Then, the remaining ore body in the three or four mining units in the middle is mined using the inlet filling mining method.

[0010] In some embodiments, in the method for mining a steeply inclined thick ore body between sections, when mining the ore body in the three or four mining units in the middle, a first preset height is set based on the floor of the lower section roadway. When the floor height of the layered stope is less than the first preset height, the layered stope can be mined using the upward approach mining method.

[0011] In some embodiments, in the method for mining stopes between segments of a steeply inclined thick ore body, the first preset height is set according to the maximum climbing angle of the mining equipment, and the first preset height is 10 to 12 meters.

[0012] In some embodiments, the uppermost access stope is first mined and a false bottom is laid for backfilling, and then the ore body in the mining unit is mined and backfilled in sequence according to a preset order.

[0013] In some embodiments, the method for inter-subdivided stope mining of a steeply inclined thick ore body further includes: After the lowest level of the access mining area is mined, a false bottom is laid and filled.

[0014] In some embodiments, the method for mining stopes in a steeply inclined thick ore body in subdivided sections has a stope length of 80 to 100 meters and a mining unit width of 6 to 8 meters.

[0015] Beneficial effects: The mining method provided in this application achieves systematic division of the stope and precise positioning of mining units by constructing a connecting roadway from the segmented roadway to the footwall of the ore body and arranging vein roadways along the strike of the footwall. Based on the division of the stope mining units, main ore extraction roadways, auxiliary ore extraction roadways, inclined ore extraction roadways, and corresponding pre-controlled roof roadways are constructed in the middle and on both sides of the stope. The auxiliary ore extraction roadways are located on both sides of the main ore extraction roadway, and the inclined ore extraction roadways connect the main and auxiliary ore extraction roadways, forming a main-auxiliary separation transportation network. Cutting shafts are arranged in the middle area of ​​the mining units on both sides. After the initial free face is formed by blasting, medium-deep hole blasting mining is carried out on the hanging wall and footwall of the ore body to form four ore extraction working faces. Ore from the hanging wall is transported through the main ore extraction roadway, and ore from the footwall is transported through the auxiliary ore extraction roadway, realizing coordinated ore extraction from multiple working faces and diversion of transportation paths, significantly improving ore transportation efficiency and reducing the risk of roadway congestion. In addition, after the mining of the medium-deep hole units on both sides is completed, the goaf can be quickly filled with the help of the pre-controlled roof inclined roadway, resulting in high roof connection efficiency. Ultimately, the three stages of "mining-transportation-filling" in the mine are optimized in a coordinated manner, which improves the problems of slow mining speed and low ore extraction efficiency in the traditional stratified mining mode. The overall mining cycle of the mine is shortened by the multi-free face synchronous operation mechanism. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. Wherein: Figure 1 A plan view of a conventional approach backfilling mining method (construction along the strike of the ore body) provided according to some embodiments of this application; Figure 2 A cross-section of a conventional approach backfill mining method (constructed along the strike of the ore body) provided according to some embodiments of this application; Figure 3 Longitudinal projection view of conventional approach backfill mining method (construction along the ore body strike) provided according to some embodiments of this application; Figure 4 This is a plan view of the stope after dividing it into mining units in a method for inter-segmental stope mining of a steeply inclined thick ore body according to some embodiments of this application (the following is an example of segmented plan). Figure 5 This is a cross-sectional view along direction II after the stope is divided into mining units in a method for inter-segmental stope mining of a steeply inclined thick ore body according to some embodiments of this application; Figure 6 This is a longitudinal projection view along the II-II direction after the stope is divided into mining units in a method for inter-segmental stope mining of a steeply inclined thick ore body according to some embodiments of this application. Figure 7This is a plan view of the main, auxiliary, and inclined roadways and corresponding pre-controlled top roadways in a subdivided stope mining method for steeply inclined thick ore bodies according to some embodiments of this application (the following is a subdivided plan view). Figure 8 This is a cross-sectional view of the main, auxiliary, and inclined roadways and the corresponding pre-controlled top roadway arrangement in direction II of a method for mining inter-segment stopes in a steeply inclined thick ore body according to some embodiments of this application; Figure 9 This is a longitudinal projection view of the main, auxiliary, and inclined roadways and the corresponding pre-controlled top roadway arrangement in the II-II direction of a method for mining inter-segment stopes in a steeply inclined thick ore body according to some embodiments of this application. Figure 10 This is a cross-sectional view of the borehole layout III-III direction in a method for mining inter-segmental stopes in a steeply inclined thick ore body according to some embodiments of this application.

[0017] Figure 11 This is a plan view of the ore body layout and mining route in the three intermediate mining units in a method for mining a steeply inclined thick ore body in a segmented stope according to some embodiments of this application (the following segmented plan is an example). Figure 12 A cross-sectional view along direction II of a method for mining inter-segmental stopes in a steeply inclined thick ore body according to some embodiments of this application, showing the ore body in the three intermediate mining units being arranged for layered mining. Figure 13 The longitudinal projection of the II-II direction in the stratified mining approach of the ore body in the three intermediate mining units in a method for mining a steeply inclined thick ore body between subsections according to some embodiments of this application. Figure 14 This is a schematic diagram of the arrangement of high and low ratio cemented filling bodies and false bottom after the overall filling of the stope in a segmented stope mining method for a steeply inclined thick ore body according to some embodiments of this application.

[0018] Explanation of reference numerals in the attached figures: Lower segment roadway 1, Upper segment roadway 2, Stope connecting roadway 3, Ore body footwall 4, Ore body hanging wall 5, Safety pillar 6, Access road 7, Mining unit 8, Footwall vein roadway 9, Ore extraction inclined roadway 10, Ore extraction auxiliary roadway 11, Ore extraction main roadway 12, Pre-controlled roof roadway 13, Cutting shaft 14, Medium-deep hole blasting hole 15, Ore block 16, Transportation path 17, Filling sealing wall 18, Low-ratio cemented backfill 19, High-ratio cemented backfill 20, False bottom 21. Detailed Implementation

[0019] The present application will now be described in detail with reference to the accompanying drawings and embodiments. Various examples are provided by way of explanation and not by way of limitation. In fact, those skilled in the art will understand that modifications and variations can be made to the present application without departing from the scope or spirit of the present application. For example, a feature shown or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention should fall within the scope of protection of the embodiments of the present invention.

[0020] It should be noted that the steeply dipping thick orebody described in this article refers to an orebody with a dip angle ≥ 55° and a vertical distance of 50–100 m between the hanging wall and footwall. In related mining techniques, the upward or downward approach backfilling mining method is commonly used, with layered mining and layer-by-layer backfilling as the basic model. This requires constructing multiple approaches 7 along the strike or dip of the orebody, each approach 7 executing a "mining-extraction-backfilling-maintenance" work cycle. This model suffers from low production efficiency, large support requirements, high backfilling frequency, and difficulties in coordinating multiple stopes, especially under conditions of significant orebody thickness, resulting in excessively long stope mining cycles and high labor intensity.

[0021] Therefore, this application provides a method for inter-segment stope mining of steeply dipping thick ore bodies, characterized by the following steps: S100, Step 1: From the segmented roadway construction site connecting roadway 3 to the footwall 4 of the ore body, arrange the footwall vein roadway 9 along the strike of the footwall 4 of the ore body and divide the ore room, and further divide the ore room into multiple mining units 8.

[0022] It should be noted that the segmented roadway is a transport and ventilation roadway excavated vertically at a set elevation, used to connect mining operation areas at different elevations; the stope connecting roadway 3 is the connecting roadway between the segmented roadway and the ore body; the footwall 4 is the boundary of the ore body located below the ore body in the contact surface between the ore body and the surrounding rock; the footwall vein roadway 9 is a roadway excavated along the strike of the footwall 4, used to serve subsequent mining, transport and ventilation, and its axis is basically parallel to the strike of the footwall 4; the stope is an independent mining unit after the ore body is divided along the strike or dip, and by vertically segmenting the ore body through the upper and lower segmented roadways, the stope can be further subdivided into multiple segmented stops; the mining unit 8 is a number of sub-units that are equally subdivided along the strike of the stope. This division method enables the stope to have modular mining capabilities, which facilitates the subsequent systematic management and mining of the stope.

[0023] S200, Step 2: Construct the main ore extraction roadway 12, auxiliary ore extraction roadway 11, and inclined ore extraction roadway 10 in the middle of the stope and the lower section of the two outer units. Construct the pre-controlled roof roadway 13 in the middle of the stope and the upper section of the two outer units, which is divided into the pre-controlled roof main roadway, the pre-controlled roof auxiliary roadway, and the pre-controlled roof inclined roadway. The mining units on both sides of the main ore extraction roadway are symmetrically arranged and have the same number.

[0024] It should be noted that when the number of stope mining units is odd, the middle position of the stope, that is, the middle mining unit 8, is designated as the main ore exit roadway 12; when the number of stope mining units is even, the middle position of the stope, that is, the middle position of the four middle mining units, is designated as the main ore exit roadway 12. The stope connecting roadway 3 corresponds to the position of the main ore exit roadway 12.

[0025] In this context, the upper segment roadway 2 and the lower segment roadway 1 refer to two adjacent segment roadways, with the lower segment roadway 1 having a lower elevation than the upper segment roadway 2. The main ore extraction roadway 12 is the main transport channel located in the middle of the stope and running through the entire stope. The auxiliary ore extraction roadway 11 is an auxiliary transport channel symmetrically distributed on both sides of the main ore extraction roadway 12, used to divert ore from the lower footwall and reduce the transport pressure of the main roadway. Initially, the auxiliary ore extraction roadways are located on the outermost two mining units 8 of the stope. The inclined ore extraction roadway 10 is a connecting roadway linking the main and auxiliary ore extraction roadways, dispersing transport pressure and serving as a temporary ore storage and secondary crushing function. The pre-control roof roadway 13 is an upper segment roadway constructed corresponding to the positions of the lower segment ore extraction main, auxiliary, and inclined roadways, creating conditions for subsequent medium-deep hole blasting and filling. Thus, a multi-transport channel layout with one main and two auxiliary roadways can be formed, creating conditions for rapid ore transport between the upper and lower footwalls.

[0026] S300, Step 3: Construct a cutting shaft in the middle area of ​​the two mining units. Starting from the cutting shaft, blasting mining is carried out towards the hanging wall and footwall of the ore body to form a total of four working faces. The ore after blasting in the hanging wall is transported through the main ore extraction roadway, and the ore after blasting in the footwall is transported through the auxiliary ore extraction roadway.

[0027] The hanging wall and footwall ore bodies are divided into two mining areas by the cutting shaft 14. This allows for four blasting faces within a single stope—one each on the left and right sides of the hanging wall, the left and right sides of the footwall. This four-face coordinated operation mechanism increases the number of blasting faces and the frequency of blasting operations. The ore from the hanging wall blasting is transported via the main exit roadway 12, indicating that the ore produced by the blasting of the hanging wall can be transported out of the stope via the inclined exit roadway 10 and into the main exit roadway 12 under the action of shoveling equipment. Similarly, the ore from the footwall blasting is transported directly out of the stope via the auxiliary exit roadway 11. This separate transportation path design avoids the convergence, mixing, or mutual interference of the hanging wall and footwall ore during transportation, improving transportation continuity and safety.

[0028] Optionally, the simultaneous mining method is as follows: after the pre-controlled top and auxiliary roadway construction is completed and before the cutting shaft construction is completed, downward fan-shaped blasting holes 15 are constructed along the dip of the hanging wall of the ore body on the bottom plate of the pre-controlled top and auxiliary roadway face. After the cutting shaft construction is completed, upward fan-shaped blasting holes 15 are constructed along the dip of the hanging wall of the ore body on the top plate of the vein roadway 9 in the footwall, and vertical blasting holes are constructed in the remaining areas.

[0029] This application achieves modularization of the internal spatial structure of the stope by arranging the vein roadway 9 along the strike of the ore body downslope from the segmented roadway construction stope connecting roadway 3 to the ore body downslope 4 and dividing the stope into stopes and mining units 8. By arranging the main ore extraction roadway 12, auxiliary ore extraction roadway 11, ore extraction inclined roadway 10 and corresponding pre-controlled top roadway 13 in the middle position and on both sides of the stope, a multi-transport channel with one main and two auxiliary channels is constructed. With the synchronous mining of the upper and lower ore bodies, four working faces are formed, and multiple paths are distinguished for transporting ore from the upper ore body via the main ore extraction roadway and from the lower ore body via the auxiliary ore extraction roadway. This significantly increases the ore extraction intensity per unit time, realizes the orderly diversion and transportation of ore, and significantly improves the overall ore extraction efficiency and mining efficiency of the stopes between segments of steeply dipping thick ore bodies.

[0030] It should be noted that the hanging wall and footwall areas of the ore body usually correspond to the free surface of the hanging wall or footwall, where joints are developed and the surrounding rock stability is relatively low. The fan-shaped arrangement refers to the bottom plate at the junction of the pre-controlled top auxiliary roadway 13 and the hanging wall 5 of the ore body or the top plate at the junction of the footwall vein roadway 9 and the footwall 4 of the ore body as the fan top. Multiple blasting holes 15 are arranged radially into the ore body. The axes of each hole form an angle in the same vertical plane, and their openings are located in the same roadway cross section. The bottom of the holes points to different depths and dip angles inside the ore body. Relying on the multi-angle impact superposition effect formed by the fan-shaped blasting holes, a controllable priority fracture path is constructed in the edge area of ​​the ore body, so that the blasting stress wave can be more effectively coupled to the ore-rock interface, thereby reducing the amount of residual ore, reducing the rate of large blocks and dilution, and providing ore with appropriate particle size for the continuous and efficient transportation of the subsequent main ore extraction roadway 12 and auxiliary ore extraction roadway 11.

[0031] Optionally, the method of arranging the blasting holes 15 in a fan shape is as follows: the bottom plate at the junction of the pre-controlled top auxiliary roadway 13 and the hanging wall 5 of the ore body is set as the coordinate of the top of the first row of fan-shaped holes. The angle of the first row of fan-shaped blasting holes is consistent with the dip angle of the hanging wall of the ore body. The holes are arranged in a radiating manner with 3 to 5 rows and 6 to 8 holes per row, so that the final angle reaches 90°. This ensures that the direction of stress wave propagation forms a favorable angle with the structural surface of the hanging wall and hanging wall of the ore body, thereby improving the directional crushing effect.

[0032] It should be noted that the blasting holes 15 are arranged vertically in other areas. These other areas refer to the ore body within the mining unit 8 other than the fan-shaped hole arrangement. The stress distribution in these areas is relatively uniform, and the requirements for blasting directionality are lower. Vertical arrangement means that the axes of multiple blasting holes 15 are basically parallel to the vertical direction, and the hole opening and bottom maintain approximately the same horizontal projection position. Each hole is arranged in a straight line or a slightly staggered arrangement along the vertical direction. In areas with relatively stable geological conditions, the use of standardized vertical hole arrangement can reduce the frequency of drilling rig angle adjustment and positioning error, improve the hole formation quality and charge density of medium and deep holes, ensure the uniform release of blasting energy, avoid local over-blasting or under-blasting, thereby maintaining the overall stability of the mining area and providing a flat and regular goaf outline for subsequent backfilling operations.

[0033] Alternatively, the method for vertically arranging the blasting holes 15 is as follows: taking the roof of the auxiliary ore roadway 11 as the baseline, the holes are arranged at equal intervals along the auxiliary ore roadway 11, the hole depth is determined according to the height of the mining unit 8, and the axis of all holes is perpendicular to the horizontal plane.

[0034] This application employs a fan-shaped arrangement of blasting holes 15 in the hanging wall and footwall of the ore body to enhance the reflection and guiding effect of blasting stress waves on the free surface, thereby improving the caving efficiency of ore along the dip direction. Simultaneously, a vertical arrangement of blasting holes 15 is used in other areas to ensure drilling accuracy and blasting process stability. The two arrangement methods are spatially distinct and functionally complementary, jointly optimizing the spatial distribution and temporal sequence of blasting energy within the ore body. This not only improves the utilization rate of explosive energy and the uniformity of ore crushing but also reduces the disturbance intensity to the surrounding rock, thereby ensuring continuous ore production while enhancing the overall safety and controllability of the mining area.

[0035] In some embodiments, the method further includes: after the mining of the medium-deep borehole units located on both sides is completed, laying waterproof membrane, geotextile, steel mesh and other false bottom materials on the bottom plate of the goaf and welding them together; constructing a half-face filling sealing wall 18 at the junction of the auxiliary ore roadway 11 and the footwall vein roadway 9, and the auxiliary ore roadway 11 and the ore inclined roadway 10 to fill the goaf with high-ratio cemented filling material, with a thickness of about 1.0m, forming a false bottom 21. Subsequently, at the junction of the auxiliary ore roadway 11 and the footwall vein roadway 9, and the auxiliary ore roadway 11 and the ore inclined roadway 10, the full-height filling sealing wall 18 is completed; and low-ratio cemented filling material and high-ratio cemented filling material are injected into the goaf sequentially through the pre-controlled roof inclined roadway 13, wherein the low-ratio filling material is used for preliminary leveling and venting, and the high-ratio filling material is used for final roof connection and pressure bearing.

[0036] like Figure 13As shown, the goaf is filled with low-ratio cemented backfill 19, high-ratio cemented backfill 20, and a false bottom 21. The backfilling operation adopts a segmented backfilling method. According to the height of the goaf, the backfilling process is divided into several vertical segments, each segment height is controlled at 2 to 3 meters. Grouting, settling and venting are completed in each segment before moving on to the next segment.

[0037] It should be noted that the junction of the auxiliary ore extraction roadway 11 and the inclined ore extraction roadway 10 refers to the three-dimensional spatial node formed by the intersection of the extension directions of the auxiliary ore extraction roadway 11 and the inclined ore extraction roadway 10. This node is located on the sidewall of the goaf of the two mining units 8 that have been completely mined, and has clear spatial positioning and structural bearing feasibility. The same applies to the junction of the auxiliary ore extraction roadway 11 and the footwall vein roadway 9. In this embodiment, this junction serves as the location for constructing the filling and sealing wall 18.

[0038] Among them, the filling sealing wall 18 refers to a temporary structure used to physically isolate the boundary of the goaf between the mined and unmined blocks. Its function is to prevent the filling material from leaking into the unmined area during the filling operation, maintain the filling pressure, and guide the filling material to flow along a predetermined path. In this embodiment, the filling sealing wall 18 is set at the junction of the ore extraction auxiliary roadway 11 and the footwall vein roadway 9, and the ore extraction auxiliary roadway 11 and the ore extraction inclined roadway 10. Its construction position is close to the edge of the mined goaf, forming a lateral blockage of the mined unit, and providing a sealed boundary condition for subsequent cemented filling of the goaf through the pre-controlled top inclined roadway 13.

[0039] Optionally, the construction method of the filling and sealing wall 18 can be as follows: first, clean up the slag and loose surrounding rock at the junction of the ore extraction auxiliary roadway 11 and the footwall vein roadway 9, and the ore extraction auxiliary roadway 11 and the ore extraction inclined roadway 10, and then use prefabricated aerated bricks to build the wall layer by layer along the contour of the roadway cross section, and reserve observation ports, exhaust ports and water filter ports.

[0040] Optionally, the construction method of the filling and sealing wall 18 may include: first, cleaning up the slag and loose surrounding rock at the junction of the auxiliary tunnel 11 and the inclined tunnel 10; erecting a steel arch frame at the junction as a supporting skeleton; after erecting wooden or iron formwork on the outside of the arch frame, pouring concrete inside as a sealing structure; and reserving observation ports, vent ports and water filter ports.

[0041] Furthermore, the construction and filling of the filling and sealing wall 18 can also be carried out in an integrated and coordinated manner. That is, after the sealing wall is constructed, the filling conduit and pressure monitoring sensor are installed simultaneously. By providing real-time feedback on the liquid level of the filling material and the pressure changes in the cavity, the grouting rate and mix ratio are dynamically adjusted to achieve uniform spreading and effective roof connection in the goaf area.

[0042] In this way, by constructing a filling and sealing wall 18 at the junction of the auxiliary ore exit roadway 11 and the footwall vein roadway 9, and the auxiliary ore exit roadway 11 and the ore exit inclined roadway 10, the goaf area is effectively isolated. With the help of the sealed space formed by the sealing wall, combined with the pre-controlled roof inclined roadway 13 as the filling inlet, the cemented filling material can fall stably along the direction of gravity and fully fill the goaf area. On this basis, by injecting filling materials with different proportions in stages, the fluidity and venting performance of the initial filling body are ensured, and the strength and roof connection quality of the final filling body are improved. Finally, the filling operation of this area is completed in a timely manner after the mining of the two side mining units 8 is completed, which significantly improves the filling speed and stability of the goaf area, and also provides reliable spatial constraints and ground pressure management basis for the subsequent gradual mining of the stope from the outside to the inside.

[0043] In some embodiments, the method further includes: After the outermost mining unit is filled, mining and filling will proceed from both sides towards the middle mining unit 8 in steps 2 and 3.

[0044] It should be noted that the positions of the two outermost mining units 8 are determined by the overall geometric layout of the stope, and directly correspond to the length of the stope, the width of the mining unit 8, and the arrangement of the safety columns 6. For example, if the stope is divided into 11 mining units 8, then the outermost mining units 8 are Unit 1 and Unit 11. Similarly, the mining unit 8 in the middle refers to the middle mining unit 8 among the multiple mining units 8 divided within the stope.

[0045] It should be noted that, taking a mine with a total of 11 mining units as an example, mining from both sides to the mining unit 8 in the middle means starting from the 1st and 11th units, and then advancing inward to the 2nd and 10th units, the 3rd and 9th units, the 4th and 8th units, the 5th and 7th units, and finally focusing on the 6th unit.

[0046] Alternatively, the method of gradually mining from both sides to the middle can be based on the stable boundary formed by the two side units that have completed mining and backfilling. The corresponding ore extraction auxiliary roadway 11 and pre-controlled top auxiliary roadway 13 of the adjacent inner side units are arranged in sequence, and the upper and lower ore bodies are mined simultaneously in the unit in the manner of step 3. After each symmetrical unit is completed, the corresponding backfilling and sealing wall 18 construction and backfilling operations are carried out.

[0047] Furthermore, the method of gradually mining from both sides towards the middle adopts a phased rhythm control approach: the first two rounds of advancement (1st to 2nd, 11th to 10th) use a combination of parameters such as medium-deep holes, large diameter holes, and high charge to improve the efficiency of a single blast; the latter two rounds of advancement (3rd to 4th, 9th to 8th) gradually reduce the hole network parameters and increase the blasting frequency to adapt to the changes in the free surface caused by the narrowing of the mining space, and to ensure the continuity of ore production and the stability of the surrounding rock.

[0048] By setting the mining sequence to "progressing from both sides to the middle", and utilizing the symmetrical roadway system arranged in step 2 and the dual-panel synchronous operation mechanism established in step 3, each round of advancement reuses the existing main mining roadway 12, auxiliary mining roadway 11 and inclined mining roadway 10 as transportation channels, so as to maintain efficient mining capacity without adding too much engineering.

[0049] In some embodiments, the method further includes: During the process of mining from both sides towards the middle mining unit 8, mining stops when three or four adjacent mining units in the middle are reached. The ore body of the three or four mining units in the middle is divided into layers from bottom to top to form multiple layered mining areas. Then, the remaining ore body in the three or four mining units in the middle is mined using the inlet filling mining method.

[0050] The three or four adjacent mining units 8 in the middle refer to the three or four mining units 8 that are centrally located, consecutive, and numbered adjacently among the multiple mining units 8 in the stope. Their specific positions are determined by the total number of units in the stope. For example, when the stope is divided into 11 mining units 8, the three adjacent mining units 8 in the middle are units 5, 6, and 7; when it is divided into 12 units, they are units 5, 6, 7, and 8. This position does not depend on the absolute number, but on the symmetry and continuity of the overall division.

[0051] Stopping mining means terminating the current medium-deep hole blasting mining mode, ceasing medium-deep hole blasting operations on the three mining units 8, and transitioning from a large-scale, high-efficiency ore extraction stage to a refined residual ore recovery stage.

[0052] The access filling mining method refers to the mining method of excavating a narrow and long tunnel (i.e., access 7) along the strike or dip direction of the ore body, and carrying out small-scale blasting, local ore extraction and immediate support within access 7. Its core difference from the medium and deep hole mining method lies in the small operating space, high ore control precision and strong controllability of the free face, which is suitable for the recovery of residual ore bodies with complex boundaries and low residual amount.

[0053] The ore body located in the three or four mining units 8 in the middle refers to all the remaining ore bodies within the space enclosed by the three or four mining units that have not yet been mined by the medium-deep hole mining method, including unmined areas left inside the unit due to reasons such as blasting boundary control, ore-rock mixture, and rock avoidance.

[0054] In this way, by actively switching to the infeed backfilling mining method when the mining progresses to three or four adjacent units in the middle of the stope, the coupling and functional complementarity of the two mining processes are achieved: the medium-deep hole mining method ensures the main mining with high capacity and high efficiency in the early stage, while the infeed backfilling mining method undertakes the recovery of residual ore in small space, with high precision and strong adaptability in the later stage. The synergy of the two not only avoids the technical bottlenecks of the medium-deep hole mining method, such as the difficulty of hole layout in narrow areas, superposition of blasting vibration, and loss of boundary control, but also overcomes the inherent defects of the infeed backfilling mining method, such as the long construction period and high cost. Ultimately, it significantly improves the mining efficiency of the stope, shortens the mining cycle, and further provides a reusable technical paradigm for the regional and phased collaborative mining of similar steeply dipping and extremely thick ore bodies.

[0055] It should be noted that when facing an extremely thick ore body, such as 120m, it is divided into the hanging wall and footwall ore bodies with a 60m (middle area) boundary. First, a cutting shaft 14 is constructed in the middle area (90m) of the hanging wall ore body, and blasting and mining are carried out simultaneously on both sides. After the mining of the hanging wall ore body is completed, a filling and sealing wall 18 is constructed at the boundary between the hanging wall and footwall ore bodies, at the junction of the auxiliary ore roadway 11 and the inclined ore roadway 10. The goaf of the hanging wall is filled with the help of the pre-controlled top inclined roadway 13.

[0056] Following this pattern, after the upper goaf is filled, a cutting shaft 14 is constructed in the middle area (30m) of the lower ore body, with simultaneous blasting and mining on both sides. After the lower ore body is mined, a filling and sealing wall 18 is constructed at the junction of the auxiliary ore roadway 11 and the lower vein roadway 9, and the auxiliary ore roadway 11 and the ore inclined roadway 10. The lower goaf is then filled using the pre-controlled top inclined roadway 13. At this point, the unit mining and filling is completed.

[0057] In some embodiments, when mining the ore body in the three or four mining units 8 in the middle, a first preset height is set based on the bottom plate of the lower segment roadway 1. When the bottom plate height of the layered stope is less than the first preset height, the layered stope can be mined using the upward approach filling mining method.

[0058] The bottom plate of the lower section roadway 1 serves as the spatial reference surface for the entire stope mining operation, and is used to uniformly mark the vertical spatial position of the layered access mining area within mining unit 8.

[0059] The first preset height is a critical height threshold set based on the maximum climbing angle of the mining equipment. For example, the numerical range of the first preset height can be 10 to 12 meters. This height refers to the vertical height measured upward from the bottom plate of the lower section roadway 1 as a reference.

[0060] It should be noted that the purpose of setting this height is to distinguish the applicable mining direction for different stratified stopes. For example, when the floor height of a stratified stope is less than the first preset height, the stratified stope can be mined using the upward approach filling mining method; when the floor height of a stratified stope is greater than this height, the upward approach filling mining method cannot be used.

[0061] Among them, the upward approach 7 filling mining method is a bottom-up, layer-by-layer mining method. The approach 7 starts from the lower section roadway 1 or the bottom plate of the already filled and consolidated goaf, and is excavated along the dip or strike of the ore body to form a horizontal or near-horizontal strip-shaped approach 7. After each approach 7 is mined and filled in sequence, the stope moves upward to the next layer for mining.

[0062] The three or four mining units 8 located in the middle refer to three or four units that are geometrically central and adjacent to each other among multiple mining units 8. For example, in an 11-unit numbering system, they are units 5, 6, and 7, and in a 12-unit system, they are units 5, 6, 7, and 8. Their spatial location is determined by dividing the stope into multiple mining units 8 and by mining from both sides towards the mining unit 8 located in the middle.

[0063] By setting the first preset height based on the bottom plate of the segmented roadway 1, and determining in real time whether to select the upward approach 7 filling mining method according to the height of the bottom plate of the divided layered stope, an adaptive response to the mining method of the layered approach stope is achieved.

[0064] In some embodiments, after dividing the ore body of the three or four mining units in the middle into layers from bottom to top, the uppermost access mining area is mined first and a false bottom 21 is laid for filling. Then, the ore body in the mining unit 8 is mined and filled in sequence according to a preset order.

[0065] A false bottom refers to an artificial protective layer with load-bearing capacity and water-proof performance that is immediately constructed on the bottom plate after the mining of the medium-deep hole mining unit and the uppermost access mining area is completed. It is composed of a combination structure of false bottom materials such as waterproof board, geotextile, and steel mesh and high-ratio cemented backfill. It is located above the ore body and is used as an "artificial roof" for safe mining operations below it.

[0066] Optionally, after the construction of the auxiliary tunnel is completed, anchored threaded steel bars are pre-installed on the sidewalls to prepare for the welding of tie bars. During filling, the filling is carried out from bottom to top in the order of high, low, and high proportion cemented filling bodies. The bottom plate, after being laid with waterproof board, geotextile, and steel mesh tie bars and welded, finally forms a false bottom 21 together with the high proportion cemented filling body.

[0067] Optionally, after the lowest level access stope is mined, a false bottom 21 should also be laid for backfilling, and a high-ratio cemented backfill should be carried out on the upper part of each layer as the working floor for mining in the next level stope or the upper stope.

[0068] It should be noted that laying a false floor for the entire stope floor can ensure the safety of operations when mining the lower ore body to that location, and prevent roof collapse.

[0069] The preset sequence is a logical mining path set based on the spatial elevation relationship of each layer of the access stope and the maximum roof slope of the stope connecting roadway. For example, the preset sequence can be to first complete the mining of the [16,20]m layer access stope and lay a false bottom 21 for backfilling, then carry out the mining of the [0,4]m, [4,8]m, and [8,12]m layer access stops using the upward access backfilling mining method after combining the maximum roof slope of the stope connecting roadway, and finally complete the mining of the [12,16]m layer access stope using the downward access backfilling mining method. After the mining of the [0,4]m layer access stope is completed, a false bottom 21 is laid at the bottom of the stope for backfilling. The entire process uses the already formed false bottom 21 or the surface of the backfill as the direct support foundation for the mining of the next layer.

[0070] This application establishes an initial working platform by prioritizing the mining of the uppermost layer of the access stope, and immediately lays a false bottom 21 on it for backfilling, providing a continuous and stable structural support foundation for the mining of subsequent layers of the stope. On this basis, mining is carried out in sequence according to the preset order determined by the dual constraints of the height range of each layer of the access stope and the maximum top slope of the stope connecting roadway, thereby improving the safety, controllability and engineering continuity of the stope between the segments of the steeply dipping thick ore body in the final stage.

[0071] In some embodiments, the length of the stope is 80 to 100 meters, and the width of the mining unit 8 is 6 to 8 meters.

[0072] It should be noted that the length of the stope is 80 to 100 meters, which refers to the horizontal projection length of the stope arranged along the strike of the footwall of the ore body. This length range is determined based on the overall thickness of the steeply dipping thick ore body (50 to 100 meters), the elevation difference between the sections (15 to 18 meters), the stability requirements of the safety pillar 6 (8 to 10 meters), and the development requirements of the free face for medium-deep hole blasting. This length can ensure that a single stope has sufficient reserves to support large-scale continuous ore production, and can also control the adverse effects of the stope span on the stability of the footwall and hanging wall, avoiding the increased difficulty of roof control or the increased risk of failure of the support of the vein roadway, the main, auxiliary, and inclined ore production roadway and the corresponding pre-controlled roof roadway due to excessive length.

[0073] The width of the mining unit 8 is 6 to 8 meters, which means that the horizontal width occupied by each mining unit 8 in the direction perpendicular to the footwall inside the stope is limited to this range. This width range is set according to the working space of the rock drilling equipment, the density of the medium and deep holes, the control requirements of the blasting block size, and the reasonable spacing between the auxiliary roadway 11 and the main roadway 12. This width can ensure that sufficient temporary support structures are reserved between each mining unit 8, thereby maintaining the phased stability of the overall stope structure during the multi-unit step mining process.

[0074] By controlling the stope length within the range of 80 to 100 meters and setting the width of the mining unit 8 to 6 to 8 meters, the stope achieves an economically reasonable reserve scale in the strike direction and forms a modular mining structure with appropriate scale in the dip direction. Based on this, the design of a centrally located main extraction roadway 12, symmetrically positioned auxiliary extraction roadways 11 on both sides, an inclined extraction roadway 10 connecting the main and auxiliary roadways, and corresponding pre-controlled roof roadways 13 for upper segment construction are effectively implemented spatially, thereby ensuring the independence of the four simultaneous working faces and the non-interference of the transportation paths 17. This improves stope mining efficiency, ore transportation efficiency, and the quality of goaf backfilling.

[0075] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0076] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0077] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0078] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0079] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0080] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for segmented stope mining of steeply dipping thick ore bodies, characterized in that, Includes the following steps: Step 1: From the segmented roadway construction stope connecting roadway to the footwall of the ore body, construct the vein roadway along the strike of the footwall of the ore body and divide the stopes into multiple mining units; Step 2: Construct the main ore extraction roadway, auxiliary ore extraction roadway, and inclined ore extraction roadway in the lower section of the middle and outer two units of the stope. Construct the pre-controlled roof main roadway, pre-controlled roof auxiliary roadway, and pre-controlled roof inclined roadway in the upper section of the middle and outer two units of the stope. The mining units on both sides of the main ore extraction roadway are symmetrically arranged and have the same number. Step 3: Construct a cutting shaft in the middle area of ​​the two mining units. Starting from the cutting shaft, blasting and mining are carried out on the hanging wall and footwall of the ore body to form a total of four working faces. The ore after blasting of the hanging wall ore body is transported through the main ore extraction roadway, and the ore after blasting of the footwall ore body is transported through the auxiliary ore extraction roadway.

2. The method for segmented stope mining of a steeply dipping thick ore body according to claim 1, characterized in that, Also includes: Fan-shaped blasting holes were arranged on the upper and lower sides of the ore body, while vertical blasting holes were arranged in other areas.

3. The method for segmented stope mining of a steeply dipping thick ore body according to claim 1, characterized in that, Also includes: After the mining units on both sides have finished mining, a false bottom material is laid on the bottom plate of the goaf and reinforced with welded bars. Half-face filling and sealing walls are constructed at the junctions of the auxiliary mining roadway and the footwall vein roadway, and the auxiliary mining roadway and the inclined mining roadway, and high-ratio cemented filling material is injected into the goaf to form a false bottom. Continue to construct full-height filling and sealing walls at the junctions of the ore extraction auxiliary roadway and the footwall vein roadway, and at the junctions of the ore extraction auxiliary roadway and the ore extraction inclined roadway. The goaf is then rapidly filled by the corresponding pre-controlled top inclined roadway in the upper section.

4. The method for segmented stope mining of a steeply dipping thick ore body according to claim 1, characterized in that, Also includes: After the outermost mining unit is filled, mining and filling are carried out gradually from both sides towards the middle mining unit according to steps 2 and 3.

5. A method for segmented stope mining of a steeply dipping thick ore body according to claim 4, characterized in that, Also includes: During the process of mining from both sides towards the middle mining unit, mining stops when three or four adjacent mining units in the middle are reached. The ore body of the three or four mining units in the middle is divided into layers from bottom to top to form multiple layered mining areas. Then, the remaining ore body in the three or four mining units in the middle is mined using the inlet filling mining method.

6. The method for segmented stope mining of a steeply dipping thick ore body according to claim 5, characterized in that, When mining the ore body in the three or four mining units in the middle, the first preset height is set based on the floor of the lower segment roadway. When the floor height of the layered mining area is less than the first preset height, the layered mining area can be mined using the upward approach mining method.

7. A method for segmented stope mining of a steeply dipping thick ore body according to claim 6, characterized in that, The first preset height is set according to the maximum climbing angle of the mining equipment, and the first preset height is 10 to 12 meters.

8. A method for segmented stope mining of a steeply dipping thick ore body according to claim 6, characterized in that, First, the uppermost access mining area is mined and a false bottom is laid for backfilling. Then, the ore bodies in the mining unit are mined and backfilled in sequence according to the preset order.

9. A method for segmented stope mining of a steeply dipping thick ore body according to claim 8, characterized in that, Also includes: After the lowest level of the access mining area is mined, a false bottom is laid and filled.

10. A method for segmented stope mining of a steeply dipping thick ore body according to claim 1, characterized in that, The length of the stope is 80 to 100 meters, and the width of the mining unit is 6 to 8 meters.

Images