Grouting method and device based on differentiated zoning of residual voids in goaf

Abstract

The present invention provides a grouting method and device based on the differentiated zoning of residual voids in goafs, which relates to the field of coal mining technology. The method designs a plurality of first exploration holes at different plane positions in the longwall goaf of a coal mine, and designs a plurality of second exploration holes at different plane positions in the pillar-type goaf of a coal mine, thereby obtaining the mining crack width characteristics at different positions in the longwall goaf of a coal mine and the residual space characteristics at different positions in the pillar-type goaf of a coal mine, and then differentiates the goaf of the coal mine and performs differentiated grouting on each different partition of the goaf of the coal mine. The present invention provides a grouting method based on the differentiated zoning of residual voids in goafs, which realizes the scientific and orderly management of goafs of coal mines and improves the safety and reliability of mining and stripping operations of equipment and personnel in open-pit coal mines.

Description

Technical Field

[0001] The present invention relates to the technical field of coal mining, and in particular to a grouting method and device based on differentiated zoning of residual voids in goaf areas. Background Art

[0002] The most common forms of goaf formed by over-boundary mining in underground open-pit coal mines include longwall working face goaf, room-and-pillar goaf, independent shafts and tunnels, etc.; some underground coal mines with complex conditions may have multiple types of goaf, such as tunnel-and-pillar blasting goaf, longwall blasting goaf, longwall fully mechanized mining goaf, and a combination of longwall blasting goaf and longwall fully mechanized mining goaf.

[0003] There are several main methods for safe goaf management: managing goaf with collapsed surrounding rock and managing goaf with backfill. Existing grouting and backfilling management technologies fail to differentiate between "compacted" and "uncompacted" longwall goafs, often relying on random, unscientific grouting management. They fail to differentiate goaf types and residual spatial characteristics, and lack specific grouting control technologies. Consequently, they are unable to ensure safe mining and stripping operations for equipment and personnel in open-pit coal mines. Summary of the Invention

[0004] The present invention provides a grouting method and device based on differentiated zoning of residual voids in goaf areas, in order to solve the above-mentioned problems existing in the prior art.

[0005] The present invention provides a grouting method based on differentiated zoning of residual voids in goaf areas, comprising the following steps.

[0006] Designing a plurality of first exploration holes at different plane positions in a longwall goaf of a coal mine, and designing a plurality of second exploration holes at different plane positions in a pillar goaf of a coal mine;

[0007] Based on the plurality of first exploration holes, the mining fissure width characteristics at different positions of the longwall goaf of the coal mine are obtained; and based on the plurality of second exploration holes, the residual space characteristics at different positions of the pillar goaf of the coal mine are obtained;

[0008] Based on the mining crack width characteristics at different positions of the longwall goaf of the coal mine and the residual space characteristics at different positions of the pillar goaf of the coal mine, the coal mine goaf is differentiated and zoned;

[0009] Based on the results of the differentiated zoning, different grouting processes for coal mine goaf treatment are screened to determine different grouting processes for different zones within the coal mine goaf;

[0010] Based on the different grouting processes for different subareas in the coal mine goaf, differentiated grouting is performed on different subareas in the coal mine goaf.

[0011] According to a grouting method based on differentiated zoning of residual voids in a goaf provided by the present invention, the method of obtaining mining-induced fissure width characteristics at different locations of the longwall goaf of a coal mine based on the multiple first exploration holes comprises:

[0012] Based on the hole depths, hole diameters, and coring requirements of the plurality of first exploration holes, a current status survey is conducted on the longwall goaf of the coal mine to obtain internal fracture width development data of the plurality of first exploration holes;

[0013] Based on the internal crack width development data of the plurality of first exploration holes, a line graph of the width of the mining cracks at different depths of the longwall goaf of the coal mine and at different plane positions from the boundary of the goaf is drawn;

[0014] Based on the mining crack width broken line graph, fitting and obtaining the mining crack width curve equations at different depth positions of the longwall goaf of the coal mine and different plane positions from the goaf boundary;

[0015] Based on the mining crack width curve equation, the mining crack width characteristics at different positions of the longwall goaf of the coal mine are determined.

[0016] According to a grouting method based on differentiated zoning of residual voids in a goaf provided by the present invention, the residual spatial characteristics of different positions of the pillar-type goaf of a coal mine are obtained based on the multiple second exploration holes, including:

[0017] Based on the hole depths, hole diameters, and coring requirements of the multiple second exploration holes, a current status survey is conducted on the coal mine goaf to obtain residual pore volume parameters and stability parameters at different locations of the coal mine goaf; wherein the residual pore volume parameters include the length, width, and height of the residual voids at different locations of the coal mine goaf; and the stability parameters include the lithology and water accumulation properties of the residual voids at different locations of the coal mine goaf;

[0018] Based on the residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf, the residual space characteristics at different positions of the coal mine pillar goaf are determined.

[0019] According to the present invention, a grouting method based on differential zoning of residual voids in goaf is provided. The method comprises:

[0020] Based on the mining fissure width characteristics at different positions of the coal mine longwall goaf and the residual space characteristics at different positions of the coal mine pillar goaf, the coal mine goaf is divided into at least two of the four types: longwall compaction area, longwall non-compaction area, longwall independent shaft and tunnel area, and pillar mining area.

[0021] According to the present invention, a grouting method based on differentiated zoning of residual voids in a goaf is provided. Before performing differentiated grouting on different zones in the goaf based on the different grouting processes for different zones in the goaf, the method comprises:

[0022] determining that water accumulation in the goaf is formed in different subareas of the goaf;

[0023] Determining the water level or height of the water in the goaf based on the water in the goaf;

[0024] Based on the water level or height of the water in the goaf, design a drainage plan for different subareas of the goaf before grouting;

[0025] Based on the drainage scheme, drainage construction is carried out in different zones of the coal mine goaf.

[0026] According to the present invention, a grouting method based on differentiated zoning of residual voids in goaf areas is provided, the method further comprising:

[0027] Designing one or more third exploration holes in different subareas of the coal mine goaf after grouting;

[0028] Based on the one or more third exploration holes, a grouting effect test is performed to obtain a test result; the test result includes a filling rate of residual voids in each different subarea of ​​the coal mine goaf, a strength of the grouting filling body in each different subarea of ​​the coal mine goaf, and a water level in each different subarea of ​​the coal mine goaf;

[0029] Based on the detection results, a plan view of the slurry diffusion range is drawn.

[0030] The present invention also provides a grouting device based on differentiated zoning of residual voids in goaf, comprising the following modules:

[0031] A drilling module is used to design a plurality of first exploration holes at different plane positions in a longwall goaf of a coal mine, and to design a plurality of second exploration holes at different plane positions in a pillar goaf of a coal mine;

[0032] a feature module for obtaining, based on the plurality of first exploration holes, mining fissure width features at different locations of the longwall goaf of the coal mine, and obtaining, based on the plurality of second exploration holes, residual space features at different locations of the pillar goaf of the coal mine;

[0033] A partitioning module is used to perform differentiated partitioning of the coal mine goaf based on the mining crack width characteristics at different positions of the coal mine longwall goaf and the residual space characteristics at different positions of the coal mine pillar goaf;

[0034] A determination module, configured to screen different grouting processes for coal mine goaf treatment based on the results of the differentiated zoning, and determine different grouting processes for different zones within the coal mine goaf;

[0035] The grouting module is used to perform differentiated grouting on different partitions in the coal mine goaf based on the different grouting processes for different partitions in the coal mine goaf.

[0036] The present invention also provides an electronic device comprising a memory, a processor and a computer program stored in the memory and runnable on the processor. When the processor executes the computer program, it implements any of the above-described grouting methods based on differentiated zoning of residual voids in goafs.

[0037] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the grouting method based on differentiated zoning of residual voids in the goaf as described above is implemented.

[0038] The present invention also provides a computer program product, comprising a computer program, which, when executed by a processor, implements any of the above-described grouting methods based on differentiated zoning of residual voids in goafs.

[0039] The present invention provides a grouting method based on differentiated zoning of residual voids in goafs, which designs a plurality of first exploration holes at different planar positions in a longwall goaf of a coal mine, and designs a plurality of second exploration holes at different planar positions in a pillar-type goaf of a coal mine, so as to obtain the mining crack width characteristics at different positions in the longwall goaf of a coal mine and the residual space characteristics at different positions in the pillar-type goaf of a coal mine, and then, based on the mining crack width characteristics at different positions in the longwall goaf of a coal mine and the residual space characteristics at different positions in the pillar-type goaf of a coal mine, the goaf of a coal mine is differentiated and zoned, and based on the results of the differentiated zoning, different grouting processes for the management of the goaf of a coal mine are screened, and different grouting processes for different zones in the goaf of a coal mine are determined, and finally, differentiated grouting is performed on different zones in the goaf of a coal mine, thereby realizing scientific and orderly management of the goaf of a coal mine and improving the safety and reliability of mining and stripping operations of equipment and personnel in open-pit coal mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 It is a flow chart of a grouting method based on differentiated zoning of residual voids in goaf provided by the present invention.

[0042] Figure 2 It is a schematic diagram of the plane layout of longwall goaf exploration holes in a grouting method based on differentiated zoning of residual voids in goaf provided by the present invention.

[0043] Figure 3 It is a schematic diagram of the plane layout of exploration holes in a goaf with pillars in a grouting method based on differentiated zoning of residual voids in the goaf provided by the present invention.

[0044] Figure 4 It is a line graph of the width of mining-induced cracks at different depth positions in a longwall goaf and at different plane positions from the goaf boundary in a grouting method based on differentiated zoning of residual voids in the goaf provided by the present invention.

[0045] Figure 5 This is a graph of the change in mining crack width at different depth positions in a longwall goaf and at different plane positions from the goaf boundary in a grouting method based on differentiated zoning of residual voids in the goaf provided by the present invention.

[0046] Figure 6It is a schematic plan view of the differentiated zoning of coal mine goaf in a grouting method based on the differentiated zoning of residual voids in the goaf provided by the present invention.

[0047] Figure 7 It is a schematic diagram of the slurry diffusion range in a grouting method based on differentiated zoning of residual voids in goaf provided by the present invention.

[0048] Figure 8 It is a structural schematic diagram of a grouting device based on differentiated zoning of residual voids in goaf provided by the present invention.

[0049] Figure 9 It is a schematic diagram of the physical structure of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0050] The stability of coal mine goafs is an extremely complex issue. It is not only related to geological mining conditions such as the depth, inclination, and thickness of the mined ore body, the lithology, occurrence state, thickness, physical and mechanical properties of the overlying strata, geological structure, site topography, hydrogeological conditions, mining area, roof management methods, number of mining operations, and mining methods, but is also closely related to the type, size, and location of overhead loads. The most common goafs formed by over-the-counter mining in underground open-pit coal mines include longwall face goafs, room-and-pillar goafs, and independent shafts and lanes. Some underground coal mines with complex conditions may have multiple types of goafs, including lane-and-pillar blasting goafs, longwall blasting goafs, longwall fully mechanized mining goafs, and a combination of longwall blasting goafs and longwall fully mechanized mining goafs.

[0051] Due to the articulated structure of longwall mining in underground coal mines, the porosity and compaction levels inevitably differ between the boundary areas and the central portion of the working face. The tunnel / room-and-pillar mining method involves leaving coal pillars of varying shapes inside the coal room. These pillars temporarily support the roof while the room is being mined, and are systematically retracted after the room is mined. The shape of the coal pillars is categorized as either blocky or strip-shaped. The tunnel / room-and-pillar mining method offers advantages such as low equipment investment, integrated mining and excavation, a short construction period, rapid coal production, and flexible equipment operation and rapid relocation.

[0052] In the past few decades, due to the irrational industrial structure and in pursuit of quick benefits, many coal mines have used the tunnel / room-and-pillar mining method to rapidly mine shallow coal seams, resulting in large areas of suspended roofs in tunnel / room-and-pillar goafs. As time went on, a series of disasters were triggered by the influence of water, air, disturbances caused by mining of coal seam groups (mining activities in adjacent coal seams), and ground production activities (ground construction, pressure and vibration of ground equipment, etc.).

[0053] Furthermore, these tunnel-type and room-and-pillar goafs are scattered across the mines, varying in size, shape, and stratigraphic structure. Furthermore, due to incomplete, lost, or insufficient design data, the locations and boundaries of many goafs remain uncertain. Open-pit mining in these areas is bound to lead to accidents such as roof collapse, falling equipment, and casualties. Therefore, it is crucial to rationally determine the thickness of the safe, anti-collapse coal pillar and the safe, waterproof coal pillar, and to complete the remediation of these underground goafs before the open-pit mine reaches these critical thicknesses.

[0054] The essence of goaf safety management is to shift stress concentration areas, alleviate the degree of stress concentration in the rock mass, and achieve a new relative stress balance, thereby controlling and managing ground pressure and ensuring safe mine production. Goaf safety management is technically demanding and challenging, and has always been a key area of ​​research in mine rock mechanics. The technical methods for goaf safety management vary depending on the deposit's occurrence conditions and mining processes. Research suggests that regardless of the technical method, they all aim to improve the stress distribution in the surrounding rock, reduce stress concentration, prevent excessive rock deformation, and control the extent of rock movement, ultimately eliminating hidden dangers in the goaf, avoiding disasters, and achieving safe production.

[0055] The main methods for safe goaf management include: caving the surrounding rock (i.e., caving), filling, supporting the goaf with permanent pillars, and isolating and clearing the goaf. Each method has its own applicable conditions and limitations.

[0056] For example, the caving method for treating goaf requires drilling into the goaf, and at the same time, it requires installing explosives at the designed position in a hole about 100m deep. The installation and detonation are difficult and not easy to implement.

[0057] In the process of filling the goaf to treat the mined-out areas, drilling and grouting construction are often carried out directly on the surface, which is quite blind. There is no differentiated zoning based on the type of goaf and the residual spatial characteristics, and no targeted treatment and control technology is proposed.

[0058] In addition, in the existing technology, the zoning method of the "design method of zoning filling rate of goaf areas of comprehensive mining working faces passing through underlying goafs", "grading and zoning management method of complex goafs" and "zoning controlled filling and continuous mining method of isolation pillars in underground goaf panels" is to artificially divide the goafs to be managed into several parts, and manage them in different areas and stages. This zoning technology cannot guide the management of complex and multi-type goafs; and the management of water-filled goafs is often carried out by first laying aggregates and then drilling and grouting in the middle. This method cannot solve the problem of slurry connection caused by water in the goaf. If applied to open-pit coal mines, there are still very large residual voids, which cannot guarantee the safe mining and stripping operations of equipment and personnel in open-pit mines.

[0059] At the same time, the existing grouting filling treatment technology does not divide the "compacted" and "non-compacted" conditions formed in the longwall goaf, and there is no scientific judgment formula or judgment standard for determining the non-compacted area. It only performs disordered and unscientific grouting treatment; there is no residual space and stability analysis for the pillar goaf, residual space and support strength and stability analysis for the residual shaft and tunnel. For various mining processes, the treatment process of complex goaf is not differentiated, and there is no process comparison or screening technology for goafs under various zoning conditions; there is no scientific basis for the spacing setting of grouting boreholes in combination with indoor experiments. , often based on construction experience to determine the hole spacing; no proposal for accurate control of slurry concentration and treatment process and grouting optimization technology based on the residual void characteristics, connectivity characteristics and partition characteristics of each goaf; no grouting fluidity assurance technology based on residual water detection and drainage has been formulated for the treatment of underlying goaf in open-pit mines; the non-top connection problem affected by the slurry water separation rate has not been considered, and no secondary slurry injection control top connection technology within the treatment area has been proposed; no grouting effect detection and evaluation has been carried out on the goaf that has been treated by grouting filling, and a comprehensive analysis and evaluation from point to surface and from qualitative to quantitative cannot be achieved.

[0060] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] The following combination Figures 1 to 9 The present invention describes a grouting method and device based on differentiated zoning of residual voids in goaf.

[0062] Figure 1 This is a flow chart of a grouting method based on differentiated zoning of residual voids in goaf provided by the present invention, as shown in FIG. Figure 1 As shown, the method includes the following steps.

[0063] Step 101: Design a plurality of first exploration holes at different plane positions in a longwall goaf of a coal mine, and design a plurality of second exploration holes at different plane positions in a pillar goaf of a coal mine.

[0064] Specifically, collect and analyze historical geological mining data, mining engineering plan, working face mining information (mining time, mining thickness, mining range, mining depth, room-and-pillar and longwall mining technology, etc.) of the coal mine goaf to be treated (including longwall goaf and pillar goaf, etc.); based on the analysis results of the basic geological mining data, design the goaf exploration plan and implement the corresponding goaf exploration work.

[0065] In the longwall goaf of a coal mine, several (any number such as 4, 5 or 6) goaf exploration holes (i.e., the first exploration holes) can be designed at different plane positions (i.e., positions at different distances from the working face boundary). The ground goaf exploration holes are designed in combination with the mining engineering plan and the working face mining process. The goaf exploration work is completed in accordance with the hole depth, hole diameter, coring requirements, color borehole television detection, sonar / 3D detection, etc. of the goaf exploration holes, and the basic data of the goaf are analyzed based on the current status survey results of the goaf.

[0066] In the embodiment of the present invention, an example of designing four first exploration holes at different plane positions in a longwall goaf of a coal mine is used for description. Figure 2 This is a schematic diagram of the plan layout of longwall goaf exploration holes in a grouting method based on differentiated zoning of residual voids in goaf provided by the present invention, such as Figure 2 As shown in the figure, in a certain open-pit mine (in order to specifically illustrate the grouting method based on differentiated zoning of residual voids in goafs provided by the present invention, a specific embodiment of the invention is selected for this open-pit coal mine, hereinafter referred to as the open-pit mine), four first exploration holes were designed in the longwall goaf: K3, K4, K5, and ZK5. These four holes were located 3m, 6m, 9m, and 26.6m away from the goaf boundary, respectively.

[0067] In the pillar-type goaf of a coal mine, several (any number such as 4, 5 or 6) goaf exploration holes (i.e., second exploration holes) can be designed at different plane positions (i.e., positions at different distances from the working face boundary). The ground goaf exploration holes are designed in combination with the mining engineering plan and the working face mining process. The goaf exploration work is completed in accordance with the hole depth, hole diameter, coring requirements, color borehole television detection, sonar / 3D detection, etc. of the goaf exploration holes, and the basic data of the goaf are analyzed based on the current status survey results of the goaf.

[0068] In the embodiment of the present invention, an example of designing seven second exploration holes at different plane positions in a coal mine goaf is used for description. Figure 3 This is a schematic diagram of the plane layout of the exploration holes in the goaf in the lane pillar type in the grouting method based on the differentiated zoning of the residual voids in the goaf provided by the present invention, such as Figure 3A total of 7 first exploration holes were designed in the open-pit mine goaf, namely K1, K2 and K6 drilling holes, ZK1, ZK2, ZK6 and ZK10 drilling holes.

[0069] By designing multiple first exploration holes at different locations in the longwall goaf of a coal mine, further exploration of the longwall goaf can be carried out to obtain the width characteristics of its mining fissures; by designing multiple second exploration holes at different locations in the pillar goaf of a coal mine, further exploration of the pillar goaf can be carried out to obtain the residual space characteristics.

[0070] Step 102: Based on the multiple first exploration holes, obtain the mining fissure width characteristics at different positions of the coal mine longwall goaf, and based on the multiple second exploration holes, obtain the residual space characteristics at different positions of the coal mine pillar goaf.

[0071] Specifically, in the embodiment of the present invention, a total of four first exploration holes are designed in the longwall goaf of the open-pit mine, namely K3, K4, K5 and ZK5 boreholes. The distances of these four boreholes from the boundary of the goaf are 3m, 6m, 9m and 26.6m respectively. In addition, the surface elevation of the construction area is flat. At the surface hole elevation +392m, the distance from the 6039 working face (continue to see Figure 2 Four first exploration holes were drilled at different locations along the boundary (3m, 6m, 9m, and 26.6m), corresponding to hole depths of 89.0m, 107.4m, 129.7m, and 148.5m, respectively. Based on the measurement data, internal fracture width data revealed by each first exploration hole can be obtained. Table 1 is a comparative table of formation damage detection within the holes provided by the present invention, as shown in Table 1.

[0072] Table 1 Comparison of formation damage detection in boreholes

[0073]

[0074] Figure 4 This is a line graph of the width of mining cracks at different depths of a longwall goaf and at different plane positions from the goaf boundary in a grouting method based on differentiated zoning of residual voids in the goaf provided by the present invention, such as Figure 4 As shown. Figure 4 The black line indicates that the width of the mining crack in the longwall goaf increases with the width of the 6039 working face (see Figure 2 ) The distance from the boundary position gradually increases and decreases. The red line shows that at the hole depth of 107.4m, the width of the mining crack in the goaf increases with the distance from the 6039 working face (see Figure 2) The blue line shows that the width of the mining crack in the goaf increases with the distance from the 6039 working face (see Figure 2 ) The trend of the boundary position distance gradually increasing and decreasing.

[0075] In this embodiment of the present invention, the variation curve of the mining crack width at a depth of 129.7m in a longwall goaf is used as an example for illustration. In this case, the equation for the mining crack width curve at different depths and different plane positions from the goaf boundary of the longwall goaf can be obtained through fitting calculation using software (such as MATLAB or simulation software) as follows:

[0076]

[0077] in, Indicates the maximum width of a single crack at different locations from the working surface boundary, x Indicates the distance to the boundary of the goaf.

[0078] Based on the above mining crack width curve equation, combined with Figure 4 As shown in the figure, at the hole depth of 129.7m, the width of the mining cracks in the longwall goaf of the coal mine increases with the width of the 6039 working face (see Figure 2 ) boundary position gradually increases and decreases, and the width of the mining crack at the 129.7m depth position in the longwall goaf is plotted as the width of the mining crack increases with the distance from the 6039 working face (see Figure 2 ) Curve of the change in width of mining-induced cracks as the distance from the boundary position gradually increases.

[0079] Figure 5 This is a graph showing the change in width of mining cracks at different depths of a longwall goaf and at different plane positions from the goaf boundary in a grouting method based on differentiated zoning of residual voids in the goaf provided by the present invention, such as Figure 5 As shown. Figure 5 The black line shows that the width of the mining crack in the longwall goaf of the coal mine increases with the width of the 6039 working face (see Figure 2 ) The red curve shows that the width of the mining crack in the longwall goaf of the coal mine decreases with the increase of the distance from the boundary position. The red curve shows that the width of the mining crack in the longwall goaf of the coal mine decreases with the increase of the distance from the 6039 working face (see Figure 2 ) The crack width variation curve shows that the crack width decreases as the distance from the boundary position gradually increases.

[0080] Similarly, the same method can also be used to obtain the corresponding mining crack width change curves of the longwall goaf of the coal mine at a hole depth of 89.0m, 107.4m or other positions.

[0081] According to the above mining crack width curve equation, the single maximum residual pore value at different positions of the top area of ​​the collapse zone and the boundary of the working face under the geological mining conditions can be obtained. It can be seen that the closer the top area of ​​the collapse zone is to the boundary of the longwall goaf (i.e. x The smaller the size, the larger the residual pores in the longwall goaf (i.e. The larger the value is), the worse the compaction of the longwall goaf is, and the farther away from the boundary of the longwall goaf is (i.e. x The larger the value is), the smaller the residual pores in the longwall goaf are (i.e. The smaller the value, the better the compaction performance of the longwall goaf. Based on the above compaction characteristics of longwall goaf, we can lay the foundation for differentiated zoning of longwall goaf, that is, we can scientifically divide longwall goaf into, for example, longwall compaction zones or longwall non-compaction zones.

[0082] In the embodiment of the present invention, seven second exploration holes are designed in the open pit goaf, namely K1, K2 and K6 boreholes and ZK1, ZK2, ZK6 and ZK10 boreholes (see Figure 3 At the same time, mining engineering plan drawings and working face operation procedures for historical goafs were collected to analyze the distribution and support characteristics of the remaining underground shafts and tunnels. The stability of the remaining shafts and tunnels was also analyzed based on the support strength of the remaining shafts and tunnels. Based on the mining engineering plan drawings and other data, surveys were conducted using the seven secondary exploration holes mentioned above to understand the residual spatial characteristics of the pillar-type goaf, including coal seam mining conditions, residual pore volume parameters, and stability parameters.

[0083] Based on anomaly records of exploration holes in the goaf, core drilling results, and a comprehensive analysis combined with color borehole television and drilling characteristics, it was determined that residual voids of 0.6 to 2.2 meters still exist in the pillar-type goaf. Specifically, ① Color borehole television detection in the K1 borehole revealed a residual void of approximately 0.7 to 1.5 meters at depths of 110.0 to 113.0 meters. ② Color borehole television detection in the K2 borehole revealed a residual void of approximately 0.6 meters at depths of 106.0 to 106.6 meters. ③ Due to severe wall fragmentation, the K6 borehole could not accurately measure fracture parameters. ④ The ZK1 borehole deviated, with no void visible. ⑤ Due to severe wall fragmentation, the ZK2 borehole could not accurately measure fracture parameters. ⑥ The ZK6 borehole is located at the intersection of a roadway in the pillar-type goaf, and the residual void height was approximately 1.7 to 2 meters. ⑦ The ZK10 borehole exhibits well-developed fractures and severe fragmentation. If open-pit mining is carried out above such residual cavities (especially when the thickness of the remaining safe coal and rock layer is small), the safety of machinery and personnel will not be guaranteed.

[0084] According to the mining engineering plan and other information, in the open-pit mine pillar goaf area, the remaining tunnels include area tunnels, working face mining tunnels, connecting tunnels, exploration tunnels, pressure relief tunnels, etc., and the chambers include parking lots, water tanks, chutes, coal chutes, connecting tunnels, refuge chambers, substations, material warehouses, etc.

[0085] In addition, the main tunnels of the 6 coal mining area within the scope of open-pit mining are generally supported by masonry. The tunnels in the pillar-type goaf of the 6 coal tunnel are supported by I-steel trapezoidal sheds (with intervals of 0.8m), and the unrecovered I-steel remains underground; the fully mechanized mining face drifts and mining area tunnels of the 6 coal lower layer are supported by anchor cables, anchor rods and metal mesh (without concrete spraying); the drifts of the 6 coal upper layer and working face are supported by I-steel trapezoidal sheds (the length and width of the residual goaf are 2.4m 2.4m section).

[0086] The cutting eyes and stop-mining lines of the mining working faces of each longwall goaf are supported by "anchor rods + hanging nets", with the distance of reinforced support being 20~25m. Some working faces are supported by π-shaped long steel beams + single pillars; the coal chute is supported by masonry; the water tanks, substations and other chambers are supported by masonry. The various support methods have different support strengths and stabilities.

[0087] Based on the support strength and design strength records of each residual shaft and tunnel, a residual shaft and tunnel support and stability analysis was conducted. It was found that the main chambers and mining area tunnels in open-pit mines can still maintain their service life for approximately 40 to 60 years in a natural, unmaintained state; the working face mining tunnels and exploration tunnels can still maintain their service life for approximately 10 to 20 years in a natural, unmaintained state. Based on the residual spatial characteristics of different locations in the pillar-type goaf, it is possible to scientifically divide the goaf into longwall independent shaft and tunnel areas or pillar mining areas.

[0088] The embodiment of the present invention obtains the mining fissure width characteristics at different positions of the longwall goaf of a coal mine based on multiple first exploration holes, and obtains the residual space characteristics at different positions of the pillar goaf of a coal mine based on multiple second exploration holes, thereby providing a scientific basis for the subsequent differentiated zoning of the coal mine goaf.

[0089] Step 103: Based on the mining fissure width characteristics at different positions of the longwall goaf of the coal mine and the residual space characteristics at different positions of the pillar goaf of the coal mine, the coal mine goaf is differentiated and partitioned.

[0090] Based on the working face layout and mining technology (continuous miner tunnel mining, room-and-pillar mining, longwall blasting and longwall fully mechanized mining, etc.) of the underlying well mining area, comprehensive goaf area survey results and mining support data, etc., the residual space in different goaf areas can be divided into zones.

[0091] For example, longwall goaf can be scientifically divided according to its compaction characteristics.

[0092] Since the closer the top area of ​​the collapse zone is to the boundary of the longwall goaf, the larger the residual pores in the longwall goaf, which means the compaction of the longwall goaf is worse; the farther the top area of ​​the collapse zone is from the boundary of the longwall goaf, the smaller the residual pores in the longwall goaf, which means the compaction of the longwall goaf is better, therefore, a first threshold value of the residual pores in the longwall goaf can be set. If it is greater than the first threshold value, it can be divided into a longwall non-compacted area; if it is less than or equal to the first threshold value, it can be divided into a longwall compacted area.

[0093] For another example, according to the residual space characteristics at different positions of the pillar-type goaf, the pillar-type goaf can be scientifically divided.

[0094] For the pillar-type goaf with residual space characteristics such as drifts, large tunnels, permanent chambers and other non-collapsed spaces, it can be divided into longwall independent shaft and tunnel areas; for the arched courtyard goaf in the pillar-type goaf, there are residual space characteristics with the maximum span less than or equal to the second threshold and the maximum height less than or equal to the third threshold, which can be divided into pillar mining areas.

[0095] For areas of out-of-boundary mining, due to the lack of drawings and materials, it is still uncertain whether there are goaf areas. They can be divided into screening blank areas for further exploration.

[0096] Figure 6 This is a schematic plan view of the differentiated zoning of coal mine goaf in a grouting method based on the differentiated zoning of residual voids in the goaf provided by the present invention, as shown in FIG. Figure 6 In the embodiment of the present invention, based on the existing mining goaf exploration results, coal mine goaf is divided into five types: Class I - longwall compaction area, Class II - longwall non-compaction area, Class III - longwall independent shaft and tunnel area, Class IV - pillar mining area and Class V - screening blank area.

[0097] The embodiment of the present invention differentiates the coal mine goaf based on the mining fissure width characteristics at different positions of the coal mine longwall goaf and the residual space characteristics at different positions of the coal mine pillar goaf, and scientifically and meticulously divides and distinguishes complex goafs with multiple differences such as mining process differences, support strength differences, residual space differences and connectivity differences, thereby providing a reliable basis for subsequent goaf grouting management.

[0098] Step 104: Based on the result of the differentiated zoning, different grouting processes for coal mine goaf treatment are screened to determine different grouting processes for different zones within the coal mine goaf.

[0099] After differentiating the coal mine goaf into different zones, the appropriate grouting process is selected for each zone to treat the goaf. The following example uses the goaf treatment of an open-pit mine as an example to illustrate this.

[0100] At present, the main methods for controlling hidden dangers of voids in underground mining areas of open-pit mines include complete grouting of residual space, partial aggregate filling of residual space, roof hydraulic fracturing, roof blasting (carbon dioxide blasting, gas-generating agent blasting, explosive blasting for coal mines, etc.), residual coal pillar blasting, coal seam floor blasting disturbance, water-rich goaf freezing, high-water / ultra-high-water material roof support, and residual coal pillar reinforcement.

[0101] Based on the residual space characteristics and support characteristics of the goaf in each zone, combined with the construction difficulty, technical feasibility, technical maturity, spatial stability after treatment, economic savings, difficulty of residual coal recovery, treatment safety and treatment effect of each grouting process, a comprehensive analysis is conducted and different grouting processes for each zone are selected, so as to achieve scientific, reasonable and safe treatment of different zones in the goaf.

[0102] Table 2 is a summary table of the characteristics of various goaf treatment methods provided by the embodiments of the present invention, as shown in Table 2.

[0103] Table 2 Summary of characteristics of various goaf treatment methods

[0104]

[0105] In the embodiment of the present invention, the goaf of the open-pit mine is relatively complex, with longwall comprehensive mechanized mining, longwall blasting and pillar mining with large variations in mining size (commonly known as arched courtyards). At the same time, there are residual tunnels and chambers such as chutes, coal chutes, transport belt tunnels, rail tunnels, connecting tunnels, water tanks, parking lots and substations in the underlying goaf. At the same time, the open-pit mine adopts blasting stripping technology, and is equipped with large-scale mining / stripping equipment to travel back and forth between various flat plates, ramps, etc., which exerts certain dynamic loads and concentrated loads on the overlying rock strata. Therefore, the coal rock layer of the open-pit mine 6 coal roof after treatment is required to have high stability.

[0106] Based on the residual space characteristics and support characteristics of the goaf in each zone, a comprehensive analysis is conducted and the processes in each zone are selected from the perspectives of construction difficulty, technical feasibility, technical maturity, spatial stability after treatment, economic savings, difficulty of residual coal recovery, treatment safety, and treatment effect.

[0107] Based on the above embodiments, when the underlying goaf is relatively complex and it is difficult to achieve the treatment effect by using only one method, two or more methods can be used to achieve the purpose of treatment. Through the comparison of treatment methods, combined with the goaf exploration results and mining technology of open-pit mines, the characteristics of goaf occurrence and residual shafts, tunnels and chambers, a comprehensive treatment process based on ground grouting and filling treatment of goafs is preliminarily selected for the characteristics of various goafs. Table 3 is a summary table of treatment methods for various goafs and residual shafts, tunnels and chambers provided by the present invention, as shown in Table 3.

[0108] Table 3 Summary of treatment methods for various goafs and residual shafts and tunnels

[0109]

[0110] The embodiment of the present invention is based on the results of differentiated zoning of open-pit mine goafs, namely five types: Class I - longwall compaction area, Class II - longwall non-compaction area, Class III - longwall independent shaft and tunnel area, Class IV - pillar mining area and Class V - screening blank area. Different grouting processes of coal mine goafs are screened to determine different treatment processes for different partitions of coal mine goafs. Based on each different treatment process, a different grouting process is determined, that is, a differentiated grouting design is performed. For example, no grouting is required for Class I - longwall compaction area, but different grouting processes need to be designed for Class II - longwall non-compaction area, Class III - longwall independent shaft and tunnel area and Class IV - pillar mining area. For Class V screening blank area, exploration must be carried out first and then the grouting process is selected.

[0111] Based on the results of differentiated zoning, the embodiment of the present invention screens different grouting processes for coal mine goaf management, determines different grouting processes for different zones within the coal mine goaf, thereby achieving effective grouting and scientific management of different zones within the coal mine goaf.

[0112] Step 105: Based on the different grouting processes for different subareas in the coal mine goaf, perform differentiated grouting on different subareas in the coal mine goaf.

[0113] Based on the established grouting processes for different sub-areas of the coal mine goaf, experiments were conducted in an indoor laboratory to determine the required grouting material ratios. Slurry fluidity data was obtained under different grouting material ratios. Based on this slurry fluidity data, the grouting material ratios were optimized to obtain the appropriate grouting material or slurry. Finally, grouting of the different sub-areas of the coal mine goaf was performed using the grouting materials or slurries with different ratios. This will be explained below using the goaf management of the open-pit mine as an example.

[0114] Based on the test objectives, laboratory tests of composite slurries with different material ratios need to be designed. All composite slurries are tested for physical and mechanical properties such as water separation rate, fluidity, consistency, wet density, compressive strength, stone density, and initial setting time. This helps to understand the physical and mechanical properties of composite slurries under different material ratios and provide data support for differentiated grouting in different zones.

[0115] For example, using a slurry with a ratio of 4:1:6:3 of water:cement:fly ash:sand as the grouting material, its water separation rate is 6%, the stone rate is 94%, the fluidity is 24.1cm, the consistency value is 128mm, and the wet density is 1.66g / cm 3 Under standard curing conditions, the compressive strength reaches 7.2MPa after 28 days of curing. Under water curing conditions, the compressive strength reaches 6.6MPa after 28 days of curing. After final setting, the stone density reaches 1.89g / cm 3 Under standard curing conditions, the initial setting time is 19 hours, and under water curing conditions, the initial setting time is 34 hours. In combination with the actual needs of the project, the different properties of the grouting under the test indicators of the composite grouting material are comprehensively considered.

[0116] Based on the residual spatial characteristics and connectivity characteristics of each sub-area of ​​the goaf, and based on the results of indoor tests, the slurry fluidity and slurry ratio of each sub-area are comprehensively determined, thereby realizing the design of differentiated grouting schemes within each sub-area. The following describes the design of differentiated grouting processes for the five types of goaf: Class I - longwall compaction area, Class II - longwall non-compaction area, Class III - longwall independent shaft and tunnel area, Class IV - pillar mining area, and Class V - screening blank area.

[0117] (1) Class I longwall compaction zone

[0118] The Class I longwall compaction zone is mainly the central area of ​​the longwall working face mining area. Its compaction performance is good. Under the load of large-scale equipment on the ground, the pores and cracks are gradually compacted. There is no risk of equipment suddenly tilting or collapsing into the goaf, nor is there a risk of people falling into the goaf.

[0119] Grouting process design: Drilling survey is mainly used to verify the development of pores and cracks in this area. The area needs to be surveyed and monitored, and it can be determined through experiments or theoretical calculations that grouting can be temporarily suspended.

[0120] (2) Class II - Longwall non-compacted area

[0121] Class II - longwall non-compacted area belongs to the non-compacted area near the mining boundary of the longwall mining face, mainly located in the large residual space area near the mining tunnel.

[0122] Scientifically determine the boundaries of the non-compacted zone: Based on the mining crack width curve equation at different depths and at different horizontal locations from the goaf boundary in a coal mine's longwall goaf, the maximum residual porosity values ​​at different locations from the working face boundary under the geological mining conditions can be calculated. Under the geological mining conditions of this open-pit mine, the maximum allowable single crack width under equipment load and allowable uneven subsidence conditions is 4 cm (the cumulative crack height within the collapse zone under these numerical conditions is approximately 0.3 m). Substituting this into the mining crack width curve equation, the boundary width D at this location from the working face is calculated to be 12 m.

[0123] Slurry proportion and grouting hole spacing design (i.e. grouting process design): Through indoor test research, it was determined that under the condition of a water: cement: fly ash: sand = 4:1:6:3 ratio, the slurry flow distance (i.e. effective diffusion distance) can be guaranteed to be 24.1 cm; referring to relevant design specifications and combining with the actual goaf conditions, considering the geological mining conditions and tunnel support and occurrence conditions of the longwall mining area, according to the indoor laboratory slurry fluidity similarity ratio and residual space height, the drilling arrangement is designed with an average hole spacing of 24 m.

[0124] (3) Category III - Longwall shaft area

[0125] Within the scope of open-pit mining, the residual tunnels (area tunnels, working face recovery tunnels, connecting tunnels, exploration tunnels, pressure relief tunnels, etc.) and chambers (parking lots, water tanks, chutes, coal chutes, connecting tunnels, refuge chambers, substations, material warehouses, etc.) in the Class III-longwall shaft area mainly serve the entire mining area / area / working face, and all have a certain support strength. Although the residual tunnels have a certain deformation, there is still a large residual space under the support conditions of "anchor rods + metal mesh + anchor cables + shotcrete".

[0126] Slurry ratio and grouting hole spacing design (i.e. grouting process design): Through indoor test research, it was determined that under the condition of water: cement: fly ash: sand = 4:1:7:3 ratio, the slurry flow distance (i.e. effective diffusion distance) is 23.5 cm; referring to relevant design specifications and combining with the actual goaf conditions, considering the shaft and tunnel support and occurrence conditions in the longwall mining area, according to the indoor laboratory slurry fluidity similarity ratio and residual space height, the drilling arrangement is designed with an average hole spacing of 27 m.

[0127] (4) Category IV - Pillar mining area

[0128] According to the survey results of the pillar-type goaf obtained by ground drilling combined with color borehole television and sonar scanning technology, although there is a certain range of roof collapse in the Class IV pillar-type mining area, there are still voids of more than 2.0m that have not been completely compacted; at the same time, although the remaining tunnels are filled with water and have a certain degree of spalling, under the conditions of wooden support, it is speculated that there are still voids of about 2.2m in height.

[0129] Slurry proportion and grouting hole spacing design (i.e. grouting process design): Through indoor test research, it was determined that under the condition of water: cement: fly ash: sand = 4:1:7:4, the slurry flow distance (i.e. effective diffusion distance) is 22.6cm; referring to relevant design specifications and combining with the actual goaf conditions, considering the shaft and tunnel support and occurrence conditions in the longwall mining area, according to the indoor laboratory slurry fluidity similarity ratio and residual space height, the drilling arrangement is designed with an average hole spacing of 32m.

[0130] (5) Category V - Screening blank area

[0131] Class V - Screening blank areas mainly include: 6029 working face, 6031 working face and 6028 south side working face and other areas were mined by tunnel boring machine, and the tunnel boring machine mining size was 4.0 2.7m; areas such as 6029, 6031 and the south working face of 6028 are first mined by tunnel boring machines, and then the top coal mining is carried out by drilling and blasting on both sides (arch courtyard); the 601 tunnel and pillar mining area is mined by the "arch courtyard" technology (collapse pits with a diameter of about 10m have appeared on the surface in some areas); 8 coal is mined by exploration tunnels, branch tunnels and other technologies to mine other independent shafts and tunnels in the area.

[0132] Grouting process design: Since the geological mining data and residual space conditions in the treatment area are still unclear, the "charging method + semi-aerial magnetic method" combined with the "drilling + color borehole television + sonar" comprehensive detection process is first used to complete the advanced detection of the goaf in this area; then the grouting process design of this area is carried out based on the detection results (slurry indoor laboratory testing, slurry ratio selection, hole diameter and hole spacing, etc.).

[0133] The embodiment of the present invention is based on different grouting processes for different partitions in the coal mine goaf, and conducts the required grouting material ratio experiments in an indoor laboratory to obtain suitable grouting materials or slurries for different partitions in the coal mine goaf, and performs differentiated grouting on different partitions in the coal mine goaf, thereby ensuring that the grouting liquid can be quickly and effectively filled into the goaf, and accurately controlling the effective diffusion distance of the slurry in each grouting borehole, thereby achieving accurate, effective, safe and reliable management of different partitions in the coal mine goaf.

[0134] The present invention provides a grouting method based on differentiated zoning of residual voids in goafs. The method comprises the following steps: designing a plurality of first exploration holes at different planar positions in a longwall goaf of a coal mine, and designing a plurality of second exploration holes at different planar positions in a pillar-type goaf of a coal mine, so as to obtain the mining crack width characteristics at different positions in the longwall goaf of a coal mine and the residual space characteristics at different positions in the pillar-type goaf of a coal mine. Then, based on the mining crack width characteristics at different positions in the longwall goaf of a coal mine and the residual space characteristics at different positions in the pillar-type goaf of a coal mine, the goaf of a coal mine is differentiated and zoned. Based on the results of the differentiated zoning, different grouting processes for the treatment of the goaf of a coal mine are screened, and different grouting processes for different zones in the goaf of a coal mine are determined. Finally, different grouting materials or slurries are configured for different zones in the goaf of a coal mine, and differentiated grouting is performed, thereby realizing scientific, orderly, precise, effective, safe and reliable treatment of the goaf of a coal mine, and improving the safety and reliability of mining and stripping operations of equipment and personnel in open-pit coal mines.

[0135] Optionally, obtaining mining fissure width characteristics at different locations of the longwall goaf of the coal mine based on the multiple first exploration holes includes:

[0136] Based on the hole depths, hole diameters, and coring requirements of the plurality of first exploration holes, a current status survey is conducted on the longwall goaf of the coal mine to obtain internal fracture width development data of the plurality of first exploration holes;

[0137] Based on the internal crack width development data of the plurality of first exploration holes, a line graph of the width of the mining cracks at different depths of the longwall goaf of the coal mine and at different plane positions from the boundary of the goaf is drawn;

[0138] Based on the mining crack width broken line graph, fitting and obtaining the mining crack width curve equations at different depth positions of the longwall goaf of the coal mine and different plane positions from the goaf boundary;

[0139] Based on the mining crack width curve equation, the mining crack width characteristics at different positions of the longwall goaf of the coal mine are determined.

[0140] Specifically, based on the hole depths, hole diameters, and coring requirements of the plurality of first exploration holes, a current status survey is conducted on the longwall goaf of the coal mine to obtain internal fracture width development data of the plurality of first exploration holes;

[0141] Based on the internal crack width development data of multiple first exploration holes, a line graph of the mining crack width at different depths of the longwall goaf of the coal mine and at different plane positions from the goaf boundary is drawn;

[0142] Based on the mining crack width broken line graph, the curve equation of mining crack width at different depths of longwall goaf and different plane positions from the goaf boundary is fitted and obtained.

[0143] Based on the mining crack width curve equation, the mining crack width characteristics at different locations in the longwall goaf of a coal mine are determined.

[0144] For example, four first exploration holes are designed at different plane positions in the longwall goaf of an open-pit mine (other numbers of first exploration holes, such as 3 or 5, can also be designed according to actual needs), namely K3, K4, K5 and ZK5 drilling holes. The distances of these four holes from the boundary of the goaf are 3m, 6m, 9m and 26.6m respectively. In addition, the surface elevation of the construction area is flat. At the surface hole elevation +392m, the distance from the 6039 working face (continue to see Figure 2 ) at different positions of the boundary (3m, 6m, 9m and 26.6m), corresponding to different positions with hole depths of 89.0m, 107.4m, 129.7m and 148.5m respectively. According to the measurement data, the internal crack width development data revealed by each first exploration hole can be obtained (continue to see Table 1). Based on the internal crack width development data revealed by each first exploration hole, a line graph of the mining crack width at different depth positions of the longwall goaf and different plane positions from the goaf boundary can be obtained (continue to see Figure 4 ).

[0145] For example, the curve of the mining crack width variation at a depth of 129.7m in a longwall goaf is used. In this case, using software (such as MATLAB or simulation software) to fit and calculate, the equation for the mining crack width curve at different depths and different plane positions from the goaf boundary can be obtained as follows:

[0146]

[0147] in, Indicates the maximum width of a single crack at different locations from the working surface boundary, x Indicates the distance to the boundary of the goaf.

[0148] Based on the above mining crack width curve equation, Figure 4 As shown in the figure, at the hole depth of 129.7m, the width of the mining cracks in the longwall goaf of the coal mine increases with the width of the 6039 working face (see Figure 2 ) boundary position gradually increases and decreases, and the width of the mining crack at the 129.7m depth position in the longwall goaf is plotted as the width of the mining crack increases with the distance from the 6039 working face (see Figure 2) Curve of the change of mining crack width as the distance from the boundary position gradually increases (see Figure 5 ).

[0149] Similarly, the same method can also be used to obtain the corresponding mining crack width change curves of the longwall goaf of the coal mine at a hole depth of 89.0m, 107.4m or other positions.

[0150] According to the above mining crack width curve equation, the single maximum residual pore value at different positions of the top area of ​​the collapse zone from the working face boundary under the geological mining conditions can be obtained. It is further concluded that the closer the top area of ​​the collapse zone is to the boundary of the longwall goaf (i.e. x The smaller the size, the larger the residual pores in the longwall goaf (i.e. The larger the value is), the worse the compaction of the longwall goaf is, and the farther away from the boundary of the longwall goaf is (i.e. x The larger the value is), the smaller the residual pores in the longwall goaf are (i.e. The smaller the value, the better the compaction of the longwall goaf.

[0151] Based on multiple first exploration holes, the embodiment of the present invention obtains the mining crack width characteristics at different positions in the longwall goaf of a coal mine, and reveals the compaction characteristics of the longwall goaf from the perspectives of quantitative calculation and qualitative analysis, thereby providing a scientific and reasonable basis for the division of different areas of the longwall goaf.

[0152] Optionally, obtaining residual spatial features of different positions of the coal mine pillar goaf based on the multiple second exploration holes includes:

[0153] Based on the hole depths, hole diameters, and coring requirements of the multiple second exploration holes, a current status survey is conducted on the coal mine goaf to obtain residual pore volume parameters and stability parameters at different locations of the coal mine goaf; wherein the residual pore volume parameters include the length, width, and height of the residual voids at different locations of the coal mine goaf; and the stability parameters include the lithology and water accumulation properties of the residual voids at different locations of the coal mine goaf;

[0154] Based on the residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf, the residual space characteristics at different positions of the coal mine pillar goaf are determined.

[0155] Specifically, a plurality of second exploration holes are designed at different planar positions of the open-pit mine goaf. Based on the hole depth, hole diameter and coring requirements of the plurality of second exploration holes, the current status survey of the coal mine goaf is carried out, and the residual pore volume parameters of the plurality of second exploration holes are obtained, including the length, width and height of the residual goaf at different positions in the coal mine goaf. At the same time, the mining engineering plan and working face operation procedures of the historical goaf are collected, and the distribution characteristics and support characteristics of the residual shafts and tunnels in the mine are analyzed. The stability of the residual shafts and tunnels is analyzed based on the support strength, lithology and water accumulation of the residual shafts and tunnels, so as to determine the residual space characteristics at different positions in the coal mine goaf.

[0156] For example, 7 second exploration holes were designed at different plane positions in the open pit goaf (see Figure 3 ), namely boreholes K1, K2, and K6, and boreholes ZK1, ZK2, ZK6, and ZK10. Based on anomaly records from exploration holes in the goaf area, core drilling results, and a comprehensive analysis combined with color borehole television and drilling characteristics, it was determined that residual cavities of 0.6 to 2.2 m still exist in the pillar-type goaf. Specifically, the following findings are as follows: ① Color borehole TV detection revealed a residual void approximately 0.7 to 1.5 meters high at depths of 110.0 to 113.0 meters in borehole K1; ② Color borehole TV detection revealed a residual void approximately 0.6 meters high at depths of 106.0 to 106.6 meters in borehole K2; ③ The K6 borehole was severely broken, preventing accurate measurement of fracture parameters; ④ The ZK1 borehole was deviated, with no void area visible; ⑤ The ZK2 borehole was severely broken, preventing accurate measurement of fracture parameters; ⑥ The ZK6 borehole was located at the intersection of a pillar-type goaf, resulting in a residual void approximately 1.7 to 2 meters high; and ⑦ The ZK10 borehole showed extensive crack development and severe fracture. Open-pit mining operations conducted above these residual voids (especially when the remaining safe coal and rock layer thickness is small) would compromise the safety of equipment and personnel.

[0157] According to mining engineering plan and other data, in the open-pit mine pillar goaf, the types of residual tunnels often include area tunnels, working face recovery tunnels, connecting tunnels, exploration tunnels and pressure relief tunnels, and the chambers often include parking lots, water tanks, chutes, coal chutes, connecting tunnels, refuge chambers, substations and material warehouses.

[0158] In addition, the main tunnels of the 6 coal mining area within the open-pit mining area are generally supported by masonry. The tunnels in the pillar-type goaf of the 6 coal roadway are supported by I-beam trapezoidal sheds (with intervals of 0.8m), and the unrecovered I-beams are left underground; the fully mechanized mining face drifts and mining area tunnels of the 6 coal lower layer are supported by anchor cables, anchor rods and metal mesh (without concrete spraying); the drifts of the 6 coal upper layer and working face are supported by I-beam trapezoidal sheds (with 2.4 2.4m section).

[0159] The cutting eyes and stop-mining lines of the mining working faces of each longwall goaf are supported by "anchor rods + hanging nets", with the distance of reinforced support being 20~25m. Some working faces are supported by π-shaped long steel beams + single pillars; the coal chute is supported by masonry; the water tanks, substations and other chambers are supported by masonry. The support strength of various support methods is different.

[0160] Based on the above embodiments, according to the geometric dimensions (length, width and height) of the residual voids of each residual shaft and tunnel, the lithology and strength (rock layer composition, thickness of each sub-layer, rock tensile and compressive and shear strength) and water accumulation (water accumulation height) of different positions of the residual shaft and tunnel, combined with the support strength and design strength records of the residual shaft and tunnel, a residual shaft and tunnel support and stability analysis is performed. It can be seen that the main chambers and mining area tunnels of the open-pit mine can still be maintained for about 40 to 60 years in a natural, maintenance-free state; the working face mining tunnels, exploration tunnels, etc. can still be maintained for about 10 to 20 years in a natural, maintenance-free state.

[0161] The embodiment of the present invention obtains the residual spatial characteristics of the pillar-type goaf in a coal mine based on multiple second exploration holes, reveals the residual spatial characteristics of the pillar-type goaf from the perspectives of quantitative calculation and qualitative analysis, and thus provides a scientific and reasonable basis for the division of different areas of the pillar-type goaf.

[0162] Optionally, the differentiated zoning of the coal mine goaf based on the mining fissure width characteristics at different positions of the coal mine longwall goaf and the residual space characteristics at different positions of the coal mine pillar goaf includes:

[0163] Based on the mining fissure width characteristics at different positions of the coal mine longwall goaf and the residual space characteristics at different positions of the coal mine pillar goaf, the coal mine goaf is divided into at least two of the four types: longwall compaction area, longwall non-compaction area, longwall independent shaft and tunnel area, and pillar mining area.

[0164] Specifically, based on the mining crack width characteristics at different locations in the longwall goaf of a coal mine and the residual space characteristics at different locations in the pillar goaf of a coal mine, the goaf of a coal mine is divided into at least two of the four types: longwall compaction area, longwall non-compaction area, longwall independent shaft and tunnel area, and pillar mining area. In addition, embodiments of the present invention can also scientifically divide more other areas based on the survey situation. For example, for areas that are still uncertain or have not been clearly explored, that is, it is not yet clear whether they are goaf areas or what type of goaf they are, they can also be divided into screening blank areas to facilitate subsequent further surveys.

[0165] For example, longwall goaf can be scientifically divided according to its compaction characteristics.

[0166] Since the closer the top area of ​​the collapse zone is to the boundary of the longwall goaf, the larger the residual pores in the longwall goaf, which means the compaction of the longwall goaf is worse; the farther the top area of ​​the collapse zone is from the boundary of the longwall goaf, the smaller the residual pores in the longwall goaf, which means the compaction of the longwall goaf is better, therefore, a first threshold value of the residual pores in the longwall goaf can be set. If it is greater than the first threshold value, it can be divided into a longwall non-compacted area; if it is less than or equal to the first threshold value, it can be divided into a longwall compacted area.

[0167] For another example, according to the residual space characteristics at different positions of the pillar-type goaf, the pillar-type goaf can be scientifically divided.

[0168] For the pillar-type goaf with residual space characteristics such as drifts, large tunnels, permanent chambers and other non-collapsed spaces, it can be divided into longwall independent shaft and tunnel areas; for the arched courtyard goaf in the pillar-type goaf, there are residual space characteristics with the maximum span less than or equal to the second threshold and the maximum height less than or equal to the third threshold, which can be divided into pillar mining areas.

[0169] For areas where out-of-boundary mining occurs, due to the lack of drawings and materials, it is still uncertain whether there are goaf areas. These areas can also be divided into screening blank areas for further exploration.

[0170] In the embodiment of the present invention, based on the existing mining goaf exploration results, the entire open-pit mine goaf can be divided into five types: Class I - longwall compaction area, Class II - longwall non-compaction area, Class III - longwall independent shaft and tunnel area, Class IV - pillar mining area and Class V - screening blank area (continue to see Figure 6 ).

[0171] The embodiment of the present invention divides the coal mine goaf into at least two of the four types: longwall compaction area, longwall non-compaction area, longwall independent shaft and tunnel area, and pillar mining area, based on the mining crack width characteristics at different locations in the longwall goaf and the residual space characteristics at different locations in the pillar goaf. In addition, for the out-of-bounds mining area, since it is not yet certain whether there is a goaf, it can also be divided into a screening blank area. The above-mentioned differentiated zoning can provide support for the subsequent differentiated grouting and effective management of such goaf.

[0172] Optionally, before performing differentiated grouting on different sub-areas in the coal mine goaf based on the different grouting processes for different sub-areas in the coal mine goaf, the method includes:

[0173] determining that water accumulation in the goaf is formed in different subareas of the goaf;

[0174] Determining the water level or height of the water in the goaf based on the water in the goaf;

[0175] Based on the water level or height of the water in the goaf, design a drainage plan for different subareas of the goaf before grouting;

[0176] Based on the drainage scheme, drainage construction is carried out in different zones of the coal mine goaf.

[0177] Specifically, before performing differentiated grouting on different partitions in the coal mine goaf based on different grouting processes for different partitions in the coal mine goaf, it is also necessary to detect whether there is water accumulation in the goaf in different partitions of the coal mine goaf. If there is no water accumulation in the goaf, grouting can be carried out normally. If it is determined that water accumulation has formed in different partitions of the coal mine goaf, the water level or water height of the water accumulation in the goaf is determined based on the water accumulation in the goaf. Then, based on the water level or water height of the water accumulation in the goaf, a drainage plan is designed for different partitions in the coal mine goaf before grouting. Finally, based on the drainage plan, drainage construction is carried out on different partitions in the coal mine goaf.

[0178] Coal-bearing strata are mostly sedimentary strata, and the Quaternary system and sandstone have good water-bearing characteristics. After the underground coal seam mining is completed, due to the development of pores and cracks in the mined rock mass, the water in the sandstone aquifer easily flows into the goaf, thus forming water accumulation in the goaf.

[0179] On the one hand, water accumulation in the goaf will dilute the concentration of the composite slurry, thereby affecting the top contact of the composite slurry, and on the other hand, it will also affect the strength of the injected slurry. Therefore, in order to ensure the slurry fluidity and the strength and top contact height of the grouting treatment process in the goaf, the present invention uses a comprehensive detection method of "electrical physical detection + drilling" to determine the water level or height of the goaf water in the goaf to be treated, and designs a drainage plan before the goaf grouting treatment based on the "static water storage capacity + dynamic replenishment capacity" of the goaf, including the design of the drainage capacity, quantity and location of the single hole / well of the pit drainage hole and the ground drainage well, and finally carries out drainage construction.

[0180] For example, in an open-pit mine, the scope of water accumulation in the goaf was initially determined through electrical physical detection, and the static water volume in the goaf was determined to be 2.04 million m3 through subsequent drilling of 6 ground holes. 3 The water level elevation is +330m. At the same time, the permeability and dynamic water supply capacity of the strata are scientifically tested during the drilling process. Based on the detection results, the design adopts the open pit water discharge capacity of 800m 3 / h of drainage holes under the pit to allow for pre-drainage. After drainage is completed, grouting and filling can be carried out.

[0181] Taking into account the fact that some water bodies still remain during the on-site grouting treatment process and that the residual space sizes in the goaf are different (the residual space sizes are not uniform, and there may be local larger spaces or local smaller spaces), in order to ensure that the grouting liquid can be quickly and effectively filled into the goaf and at the same time control the flow distance of the slurry, after the drilling of the goaf is completed, the embodiment of the present invention first conducts a detailed detection using color drilling television to grasp the hole wall and internal residual space size of each grouting hole in the goaf, and optimizes the design of the slurry concentration and aggregate addition amount based on the measured data, thereby ensuring the effective diffusion distance of the slurry.

[0182] For another example, 194 (other numbers, such as 200 or 205, can be designed according to actual needs) grouting treatment boreholes are designed at equal intervals in the goaf of an open-pit mine. After each borehole is completed, the borehole wall is first cleaned with a drilling rig, and then a color drilling TV is used to complete the borehole wall detection and 360° borehole wall expansion diagram analysis of each borehole to obtain the residual space data of the borehole wall and the area to be treated; then, based on the indoor grouting material ratio test (water-solid ratio, aggregate particle size, slurry density, fluidity, viscosity, water separation rate, setting time and uniaxial compressive strength, etc.), the grouting optimization design of each borehole under different residual space conditions is carried out; finally, through measures such as grouting time and grouting pressure control, the effective diffusion distance of the slurry in each grouting borehole is accurately controlled on the basis of ensuring that the grouting liquid can be quickly and effectively filled into the goaf.

[0183] Since any composite slurry has the problem of water separation rate, after the equally spaced slurry drilling construction and grouting are completed, combined with the goaf area survey results and the mining project plan, the goaf grouting drilling construction and grouting construction are redesigned and implemented at the intersection of the main tunnels with strong diffusion capabilities, the locations where the tunnel inclination is large and the slurry is not easy to connect to the top, the locations with large residual space in the goaf, the terrain is undulating and the water body is not easy to drain, or the goaf area survey conditions are unclear. The slurry is replenished for the second time in the space that has not been connected to the top after the previous grouting, so as to ensure slurry flow control and connection.

[0184] In an embodiment of the present invention, based on different grouting processes for different sub-areas in a coal mine goaf, before performing differentiated grouting on different sub-areas in a coal mine goaf, it is first determined whether there is water accumulation in the goaf in different sub-areas of the coal mine goaf. If there is water accumulation in the goaf, a drainage scheme is designed, and drainage construction is performed to avoid dilution of the composite slurry concentration by water accumulation in the goaf, thereby affecting the roof connection of the composite slurry, and at the same time avoid the influence of water accumulation in the goaf on the slurry strength, resulting in weak compressive strength of the goaf after grouting. In addition, in order to ensure slurry flow control and roof connection, the present invention also designs a secondary slurry injection after the first grouting, thereby improving the effectiveness and reliability of grouting in different sub-areas of the goaf.

[0185] Optionally, the present invention provides a grouting method based on differentiated zoning of residual voids in goaf, further comprising:

[0186] Designing one or more third exploration holes in different subareas of the coal mine goaf after grouting;

[0187] Based on the one or more third exploration holes, a grouting effect test is performed to obtain a test result; the test result includes a filling rate of residual voids in each different subarea of ​​the coal mine goaf, a strength of the grouting filling body in each different subarea of ​​the coal mine goaf, and a water level in each different subarea of ​​the coal mine goaf;

[0188] Based on the detection results, a plan view of the slurry diffusion range is drawn.

[0189] Specifically, after grouting is completed in different zones of the coal mine goaf, the present invention further designs multiple grouting effect exploration boreholes (i.e., third exploration holes) in the goaf to detect the grouting effect and draw a plan view of the slurry diffusion range.

[0190] The embodiment of the present invention designs a comprehensive detection scheme of "drilling + color borehole television + rock mechanics test + comprehensive evaluation". It detects and evaluates the grouting effect of the goaf that has been treated by grouting, and realizes a comprehensive analysis and evaluation of the grouting effect from point to surface and from qualitative to quantitative. Specifically, it includes the following contents:

[0191] (1) Filling rate detection: Design multiple goaf area grouting effect survey boreholes, analyze the core conditions of each layer in each test hole, and use color borehole television to detect the slurry and cavity filling rate in each hole, and at the same time calculate the residual cavity situation. Combined with data such as ground equipment and dynamic load, scientifically calculate the filling rate of the residual cavity in the goaf under the condition that the main equipment does not get stuck or overturn.

[0192] For example, in the open-pit mine's Class IV pillar mining area, 27 grouting effectiveness survey boreholes were designed to conduct grouting effect filling rate analysis; in the open-pit mine's Class III longwall independent shaft and tunnel area, 34 grouting effectiveness survey boreholes were designed to conduct grouting effect filling rate analysis; and in the open-pit mine's Class II longwall non-compacted area, 32 grouting effectiveness survey boreholes were designed to conduct grouting effect filling rate analysis. The number of these grouting effect survey boreholes can be adjusted according to actual needs. Combining data such as ground equipment and dynamic loads, and through scientific calculations, it can be determined that when the filling rate of the residual voids in each of the above-mentioned different subareas of the goaf reaches above 90%, the grouting effect is satisfactory, ensuring that the main equipment does not get stuck or overturn.

[0193] (2) Filling strength test: Based on the coring results of the test hole, uniaxial compressive strength specimens are prepared and tested for uniaxial compressive strength properties. Two groups of tests (4 to 6 specimens per group) are conducted for each hole. Combined with data such as ground equipment and dynamic loads, the strength of the grouting filling body is scientifically calculated. The strength of the grouting filling body will gradually change over time, but the strength growth will usually slow down significantly after 28 days. Therefore, the embodiment of the present invention uses the calculation of the strength of the grouting filling body after 28 days as an example to illustrate the test effect.

[0194] For example, 54 slurry groups were tested for uniaxial compressive strength in the open-pit mine's Category IV pillar mining area, 68 slurry groups were tested in the open-pit mine's Category III longwall independent tunnel area, and 64 slurry groups were tested in the open-pit mine's Category II longwall non-compacted area. Based on the loads and dynamic loads of equipment such as wheel buckets, electric shovels, and dump trucks, scientific calculations were performed to determine the 28-day strength of the grouting fill in each of these different sections of the goaf.

[0195] (3) Water level detection: Water level detection can be used to obtain the water level change trend and water accumulation status in the goaf, providing a basis for management and prevention measures.

[0196] For example, in the open-pit mining Category IV (pillar mining) area, 27 boreholes were designed to investigate grouting effectiveness and conduct water level detection and analysis. In the open-pit mining Category III (longwall independent shaft and tunnel) area, 34 boreholes were designed to investigate grouting effectiveness and conduct water level detection and analysis. In the open-pit mining Category II (longwall non-compacted area), 32 boreholes were designed to investigate grouting effectiveness and conduct water level detection and analysis. Through a comprehensive method of "electrical and physical detection + drilling", the water level in each of these different sub-areas of the goaf is determined.

[0197] Based on the above embodiment, the filling range of each different partition of the coal mine goaf is detected mainly by observation and analysis through grouting drilling and detection drilling, and the filling range of the slurry is judged by high-density drilling, so that a plan view of the slurry diffusion range can be drawn. Figure 7 This is a schematic diagram of the slurry diffusion range in a grouting method based on differentiated zoning of residual voids in goaf provided by the present invention, such as Figure 7 shown. Figure 7 (a) is a schematic diagram of the slurry diffusion range, where K1, K2, K3, K4, K5, K6, K7, K8, K9 and K10 are grouting holes used to observe and analyze the grouting effect. Figure 7 (b) in the sentence means Figure 7 (a) in the figure is a schematic cross-sectional diagram of the slurry diffusion range, which shows the slurry diffusion range from the side.

[0198] The embodiment of the present invention calculates and analyzes the stability of the residual shafts and tunnels in different partitions of the coal mine goaf after treatment based on the statistical analysis of the grouting conditions in the goaf, the comparative analysis of the drilling and borehole television observation data before and after grouting, the drilling analysis for grouting effect detection and the results of core rock mechanics tests, combined with geological mining data, to achieve a comprehensive analysis and evaluation of the grouting effect of the open-pit mine goaf from point to surface and from qualitative to quantitative, thereby further ensuring the effective grouting and scientific treatment of the open-pit mine goaf.

[0199] The following describes a grouting device based on differentiated zoning of residual voids in goaf provided by the present invention. The grouting device based on differentiated zoning of residual voids in goaf described below and the grouting method based on differentiated zoning of residual voids in goaf described above can be referenced to each other.

[0200] Based on any of the above embodiments, Figure 8 This is a structural diagram of a grouting device based on differentiated zoning of residual voids in goaf provided by the present invention, such as Figure 8 As shown, an embodiment of the present invention provides a grouting device based on differentiated zoning of residual voids in a goaf, comprising a drilling module 801, a feature module 802, a zoning module 803, a determination module 804, and a grouting module 805, wherein:

[0201] The drilling module 801 is used to design multiple first exploration holes at different planar positions of the longwall goaf of a coal mine, and to design multiple second exploration holes at different planar positions of the pillar goaf of a coal mine; the feature module 802 is used to obtain the mining crack width characteristics at different positions of the longwall goaf of a coal mine based on the multiple first exploration holes, and to obtain the residual space characteristics at different positions of the pillar goaf of a coal mine based on the multiple second exploration holes; the partitioning module 803 is used to perform differentiated partitioning of the coal mine goaf based on the mining crack width characteristics at different positions of the longwall goaf of a coal mine and the residual space characteristics at different positions of the pillar goaf of a coal mine; the determination module 804 is used to screen different grouting processes for coal mine goaf management based on the results of the differentiated partitioning, and determine different grouting processes for different partitions in the coal mine goaf; the grouting module 805 is used to perform differentiated grouting on different partitions in the coal mine goaf based on the different grouting processes for different partitions in the coal mine goaf.

[0202] The present invention provides a grouting device based on differentiated zoning of residual voids in goafs. The device designs a plurality of first exploration holes at different planar positions in a longwall goaf of a coal mine, and designs a plurality of second exploration holes at different planar positions in a pillar-type goaf of a coal mine, so as to obtain the mining crack width characteristics at different positions in the longwall goaf of a coal mine and the residual space characteristics at different positions in the pillar-type goaf of a coal mine. Then, based on the mining crack width characteristics at different positions in the longwall goaf of a coal mine and the residual space characteristics at different positions in the pillar-type goaf of a coal mine, the goaf of a coal mine is differentiated and zoned. Based on the results of the differentiated zoning, different grouting processes for the management of the goaf of a coal mine are screened, and different grouting processes for different zones in the goaf of a coal mine are determined. Finally, different grouting materials or slurries are configured for different zones in the goaf of a coal mine, and differentiated grouting is performed, thereby realizing scientific, orderly, precise, effective, safe and reliable management of the goaf of a coal mine, and improving the safety and reliability of mining and stripping operations of equipment and personnel in open-pit coal mines.

[0203] Figure 9 An example of a physical structure diagram of an electronic device is shown below. Figure 9 As shown, the electronic device may include: a processor 910, a communications interface 920, a memory 930, and a communication bus 940, wherein the processor 910, the communications interface 920, and the memory 930 communicate with each other via the communication bus 940. The processor 910 may call the logic instructions in the memory 930 to execute a grouting method based on differential zoning of residual voids in the goaf, the method comprising:

[0204] Designing a plurality of first exploration holes at different plane positions in a longwall goaf of a coal mine, and designing a plurality of second exploration holes at different plane positions in a pillar goaf of a coal mine;

[0205] Based on the plurality of first exploration holes, the mining fissure width characteristics at different positions of the longwall goaf of the coal mine are obtained; and based on the plurality of second exploration holes, the residual space characteristics at different positions of the pillar goaf of the coal mine are obtained;

[0206] Based on the mining crack width characteristics at different positions of the longwall goaf of the coal mine and the residual space characteristics at different positions of the pillar goaf of the coal mine, the coal mine goaf is differentiated and zoned;

[0207] Based on the results of the differentiated zoning, different grouting processes for coal mine goaf treatment are screened to determine different grouting processes for different zones within the coal mine goaf;

[0208] Based on the different grouting processes for different subareas in the coal mine goaf, differentiated grouting is performed on different subareas in the coal mine goaf.

[0209] Furthermore, the logic instructions in the aforementioned memory 930 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product, stored in a storage medium, includes instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0210] On the other hand, the present invention further provides a computer program product, comprising a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the grouting method based on differentiated zoning of residual voids in a goaf provided by the above methods, the method comprising:

[0211] Designing a plurality of first exploration holes at different plane positions in a longwall goaf of a coal mine, and designing a plurality of second exploration holes at different plane positions in a pillar goaf of a coal mine;

[0212] Based on the plurality of first exploration holes, the mining fissure width characteristics at different positions of the longwall goaf of the coal mine are obtained; and based on the plurality of second exploration holes, the residual space characteristics at different positions of the pillar goaf of the coal mine are obtained;

[0213] Based on the mining crack width characteristics at different positions of the longwall goaf of the coal mine and the residual space characteristics at different positions of the pillar goaf of the coal mine, the coal mine goaf is differentiated and zoned;

[0214] Based on the results of the differentiated zoning, different grouting processes for coal mine goaf treatment are screened to determine different grouting processes for different zones within the coal mine goaf;

[0215] Based on the different grouting processes for different subareas in the coal mine goaf, differentiated grouting is performed on different subareas in the coal mine goaf.

[0216] In another aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to perform the grouting method based on the differentiated zoning of residual voids in a goaf provided by the above methods, the method comprising:

[0217] Designing a plurality of first exploration holes at different plane positions in a longwall goaf of a coal mine, and designing a plurality of second exploration holes at different plane positions in a pillar goaf of a coal mine;

[0218] Based on the plurality of first exploration holes, the mining fissure width characteristics at different positions of the longwall goaf of the coal mine are obtained; and based on the plurality of second exploration holes, the residual space characteristics at different positions of the pillar goaf of the coal mine are obtained;

[0219] Based on the mining crack width characteristics at different positions of the longwall goaf of the coal mine and the residual space characteristics at different positions of the pillar goaf of the coal mine, the coal mine goaf is differentiated and zoned;

[0220] Based on the results of the differentiated zoning, different grouting processes for coal mine goaf treatment are screened to determine different grouting processes for different zones within the coal mine goaf;

[0221] Based on the different grouting processes for different subareas in the coal mine goaf, differentiated grouting is performed on different subareas in the coal mine goaf.

[0222] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0223] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a necessary general-purpose hardware platform, or of course, hardware. Based on this understanding, the essence of the above technical solution, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, or an optical disk, and includes a number of instructions for causing a computer device (such as a personal computer, server, or network device) to execute the methods described in each embodiment or certain portions of the embodiments.

[0224] It should be noted that, in this article, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be noted that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0225] It should also be noted that the terms "first," "second," and "third," etc., used in the present invention are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application can be implemented in an order other than that illustrated or described herein. Furthermore, the objects distinguished by "first," "second," and "third" are generally of the same type, and do not limit the number of objects. For example, the first object can be one or more.

[0226] In the embodiments of the present application, "determine B based on A" means that the factor A must be considered when determining B. It is not limited to "B can be determined based on A alone", and should also include: "determine B based on A and C", "determine B based on A, C and E", "determine C based on A, and further determine B based on C", etc. It can also include taking A as a condition for determining B, for example, "when A meets the first condition, use the first method to determine B"; for example, "when A meets the second condition, determine B", etc.; for example, "when A meets the third condition, determine B based on the first parameter", etc. Of course, it can also be a condition that takes A as a factor in determining B, for example, "when A meets the first condition, use the first method to determine C, and further determine B based on C", etc.

[0227] In the present invention, the term "plurality" refers to two or more than two, and other quantifiers are similar to it.

[0228] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A grouting method based on differentiated zoning of residual voids in goaf, characterized in that: include: Designing a plurality of first exploration holes at different plane positions in a longwall goaf of a coal mine, and designing a plurality of second exploration holes at different plane positions in a pillar goaf of a coal mine; Based on the plurality of first exploration holes, the mining fissure width characteristics at different positions of the longwall goaf of the coal mine are obtained; and based on the plurality of second exploration holes, the residual space characteristics at different positions of the pillar goaf of the coal mine are obtained; Based on the mining crack width characteristics at different positions of the longwall goaf of the coal mine and the residual space characteristics at different positions of the pillar goaf of the coal mine, the coal mine goaf is differentiated and zoned; Based on the results of the differentiated zoning, different grouting processes for coal mine goaf treatment are screened to determine different grouting processes for different zones within the coal mine goaf; Based on the different grouting processes for different sub-areas in the coal mine goaf, differentiated grouting is performed on different sub-areas in the coal mine goaf; The obtaining, based on the plurality of first exploration holes, mining-induced fissure width characteristics at different locations of the longwall goaf of the coal mine includes: Based on the hole depths, hole diameters, and coring requirements of the plurality of first exploration holes, a current status survey is conducted on the longwall goaf of the coal mine to obtain internal fracture width development data of the plurality of first exploration holes; Based on the internal crack width development data of the plurality of first exploration holes, a line graph of the width of the mining cracks at different depths of the longwall goaf of the coal mine and at different plane positions from the boundary of the goaf is drawn; Based on the mining crack width broken line graph, fitting and obtaining the mining crack width curve equations at different depth positions of the longwall goaf of the coal mine and different plane positions from the goaf boundary; Determining mining crack width characteristics at different locations of the longwall goaf of the coal mine based on the mining crack width curve equation; The obtaining of residual spatial features of different positions of the coal mine pillar goaf based on the plurality of second exploration holes includes: Based on the hole depths, hole diameters, and coring requirements of the multiple second exploration holes, a current status survey is conducted on the coal mine goaf to obtain residual pore volume parameters and stability parameters at different locations of the coal mine goaf; wherein the residual pore volume parameters include the length, width, and height of the residual voids at different locations of the coal mine goaf; and the stability parameters include the lithology and water accumulation properties of the residual voids at different locations of the coal mine goaf; Based on the residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf, the residual space characteristics at different positions of the coal mine pillar goaf are determined.

2. The grouting method based on differentiated zoning of residual voids in goaf according to claim 1 is characterized in that: The differentiated zoning of the coal mine goaf based on the mining fissure width characteristics at different positions of the coal mine longwall goaf and the residual space characteristics at different positions of the coal mine pillar goaf includes: Based on the mining fissure width characteristics at different positions of the coal mine longwall goaf and the residual space characteristics at different positions of the coal mine pillar goaf, the coal mine goaf is divided into at least two of the four types: longwall compaction area, longwall non-compaction area, longwall independent shaft and tunnel area, and pillar mining area.

3. The grouting method based on differentiated zoning of residual voids in goaf according to claim 1 is characterized in that: Before performing differentiated grouting on different sub-areas in the goaf of a coal mine based on the different grouting processes for different sub-areas in the goaf of a coal mine, the method includes: determining that water accumulation in the goaf is formed in different subareas of the goaf; Determining the water level or height of the water in the goaf based on the water in the goaf; Based on the water level or height of the water in the goaf, design a drainage plan for different subareas of the goaf before grouting; Based on the drainage scheme, drainage construction is carried out in different zones of the coal mine goaf.

4. The grouting method based on differentiated zoning of residual voids in goaf according to claim 1, characterized in that: The method further comprises: Designing one or more third exploration holes in different subareas of the coal mine goaf after grouting; Based on the one or more third exploration holes, a grouting effect test is performed to obtain a test result; the test result includes a filling rate of residual voids in each different subarea of ​​the coal mine goaf, a strength of the grouting filling body in each different subarea of ​​the coal mine goaf, and a water level in each different subarea of ​​the coal mine goaf; Based on the detection results, a plan view of the slurry diffusion range is drawn.

5. A grouting device based on differentiated zoning of residual voids in goaf, characterized in that: include: A drilling module is used to design a plurality of first exploration holes at different plane positions in a longwall goaf of a coal mine, and to design a plurality of second exploration holes at different plane positions in a pillar goaf of a coal mine; a feature module for obtaining, based on the plurality of first exploration holes, mining fissure width features at different locations of the longwall goaf of the coal mine, and obtaining, based on the plurality of second exploration holes, residual space features at different locations of the pillar goaf of the coal mine; A partitioning module is used to perform differentiated partitioning of the coal mine goaf based on the mining crack width characteristics at different positions of the coal mine longwall goaf and the residual space characteristics at different positions of the coal mine pillar goaf; A determination module, configured to screen different grouting processes for coal mine goaf treatment based on the results of the differentiated zoning, and determine different grouting processes for different zones within the coal mine goaf; A grouting module, configured to perform differentiated grouting on different sub-areas in the coal mine goaf based on the different grouting processes for the different sub-areas in the coal mine goaf; The obtaining, based on the plurality of first exploration holes, mining-induced fissure width characteristics at different locations of the longwall goaf of the coal mine includes: Based on the hole depths, hole diameters, and coring requirements of the plurality of first exploration holes, a current status survey is conducted on the longwall goaf of the coal mine to obtain internal fracture width development data of the plurality of first exploration holes; Based on the internal crack width development data of the plurality of first exploration holes, a line graph of the width of the mining cracks at different depths of the longwall goaf of the coal mine and at different plane positions from the boundary of the goaf is drawn; Based on the mining crack width broken line graph, fitting and obtaining the mining crack width curve equations at different depth positions of the longwall goaf of the coal mine and different plane positions from the goaf boundary; Determining mining crack width characteristics at different locations of the longwall goaf of the coal mine based on the mining crack width curve equation; The obtaining of residual spatial features of different positions of the coal mine pillar goaf based on the plurality of second exploration holes includes: Based on the hole depths, hole diameters, and coring requirements of the multiple second exploration holes, a current status survey is conducted on the coal mine goaf to obtain residual pore volume parameters and stability parameters at different locations of the coal mine goaf; wherein the residual pore volume parameters include the length, width, and height of the residual voids at different locations of the coal mine goaf; and the stability parameters include the lithology and water accumulation properties of the residual voids at different locations of the coal mine goaf; Based on the residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf, the residual space characteristics at different positions of the coal mine pillar goaf are determined.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the grouting method based on differentiated zoning of residual voids in goaf as described in any one of claims 1 to 4 is implemented.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the grouting method based on differentiated zoning of residual voids in goaf as claimed in any one of claims 1 to 4 is implemented.

8. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the grouting method based on differentiated zoning of residual voids in goaf as claimed in any one of claims 1 to 4 is implemented.

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