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

Abstract

The invention provides a grouting method and device based on goaf residual gap differentiated partition, and relates to the technical field of coal mining. According to the method, a plurality of first exploration holes are designed in different plane positions of a coal mine long-wall type goaf, a plurality of second exploration holes are designed in different plane positions of a coal mine roadway column type goaf, and the goaf residual gap differentiated partition is obtained; therefore, mining-induced fracture width characteristics of different positions of the long-wall goaf of the coal mine and residual space characteristics of different positions of the roadway-pillar goaf of the coal mine are obtained, then the coal mine goaf is differentially partitioned, and different partitions of the coal mine goaf are differentially grouted. According to the grouting method based on differentiated zoning of the residual gaps in the goaf, scientific and orderly treatment of the goaf of the coal mine is achieved, and the safety and reliability of mining and stripping operation of equipment and personnel of an open pit coal mine are improved.

Description

Technical Field

[0001] The 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 areas formed by cross-boundary mining in underground open-pit coal mines include longwall working face goaf areas, room-and-pillar goaf areas, independent shafts and tunnels, etc.; some underground coal mines with complex conditions may have multiple types of goaf areas, such as tunnel-and-pillar blasting goaf areas, longwall blasting goaf areas, longwall fully mechanized mining goaf areas, and a combination of longwall blasting goaf areas and longwall fully mechanized mining goaf areas.

[0003] There are mainly several methods for safe management of goaf: management of goaf by surrounding rock collapse, management of goaf by filling method, etc. The existing grouting filling management technology does not divide the "compacted" and "non-compacted" areas formed in longwall goaf, and often only conducts disorderly and unscientific grouting management, without differentiated division according to the type of goaf and residual space characteristics, and at the same time, no targeted grouting management control technology is proposed, which cannot guarantee the safe mining and stripping operations of 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, so as 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 of the longwall goaf of the coal mine, and designing a plurality of second exploration holes at different plane positions of the pillar goaf of the coal mine; Based on the multiple first exploration holes, the mining crack width characteristics at different positions of the longwall goaf of the coal mine are obtained, and based on the multiple 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 goaf of the coal mine 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 in the coal mine goaf; 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.

[0007] According to a grouting method based on differential zoning of residual voids in goaf provided by the present invention, the method of obtaining the mining crack width characteristics at different positions of the longwall goaf of the coal mine based on the multiple first exploration holes 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; Based on the mining fissure width curve equation, the mining fissure width characteristics at different positions of the longwall goaf of the coal mine are determined.

[0008] According to a grouting method based on differential zoning of residual voids in goaf provided by the present invention, the residual space characteristics of different positions of the goaf of the coal mine are obtained based on the multiple second exploration holes, including: Based on the hole depths, hole diameters and coring requirements of the multiple second exploration holes, a current situation survey is conducted on the coal mine pillar goaf area to obtain residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf area; wherein the residual pore volume parameters include the length, width and height of the residual goaf areas at different positions of the coal mine pillar goaf area; the stability parameters include the lithology and water accumulation properties of the residual goaf areas at different positions of the coal mine pillar goaf area; Based on the residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf area, the residual space characteristics at different positions of the coal mine pillar goaf area are determined.

[0009] According to a grouting method based on differential zoning of residual voids in goaf provided by the present invention, the goaf is differentiated and zoned 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, including: 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.

[0010] According to a grouting method based on differential zoning of residual voids in a goaf provided by the present invention, before performing differential grouting on different partitions in a goaf of a coal mine based on different grouting processes for different partitions in the goaf of a coal mine, the method comprises: Determine that water is accumulated in the goaf in different subareas of the goaf; Based on the water accumulation in the goaf, determining the water level or water height of the water accumulation in the goaf; Based on the water level or height of the water in the goaf, design a drainage scheme for different subareas of the goaf before grouting; Based on the drainage scheme, drainage construction is carried out in different sub-areas of the coal mine goaf.

[0011] According to a grouting method based on differential zoning of residual voids in goaf provided by the present invention, 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 cavities in different sub-areas of the coal mine goaf, a strength of the grouting filling body in different sub-areas of the coal mine goaf, and a water level in different sub-areas of the coal mine goaf; Based on the detection results, a plan view of the slurry diffusion range is drawn.

[0012] The present invention also provides a grouting device based on the differentiated zoning of residual voids in goaf areas, comprising the following modules: A drilling module is used to design a plurality of first exploration holes at different plane positions of a longwall goaf area of ​​a coal mine, and to design a plurality of second exploration holes at different plane positions of a pillar goaf area of ​​a coal mine; A feature module, for obtaining the mining crack width features at different positions of the longwall goaf of the coal mine based on the multiple first exploration holes, and for obtaining the residual space features at different positions of the pillar goaf of the coal mine based on the multiple second exploration holes; A partitioning module, used for performing differential 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 laneway pillar goaf; A determination module, for screening different grouting processes for coal mine goaf treatment based on the result of the differentiated zoning, and determining different grouting processes for different zones in the coal mine goaf; 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.

[0013] The present invention also provides 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 the above is implemented.

[0014] 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 the differentiated zoning of residual voids in the goaf as described in any one of the above is implemented.

[0015] The present invention also provides a computer program product, comprising a computer program, which, when executed by a processor, implements any of the above-mentioned grouting methods based on differentiated zoning of residual voids in goaf.

[0016] The grouting method based on differentiated zoning of residual voids in goaf provided by the present invention 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 the coal mine is differentiatedly 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, 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

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces 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 creative work.

[0018] Figure 1 It is a schematic flow chart of a grouting method based on differentiated zoning of residual voids in goaf areas provided by the present invention.

[0019] Figure 2 It 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.

[0020] Figure 3 It is a schematic diagram of the plane layout of exploration holes in a goaf area with a pillar type in a grouting method based on differentiated zoning of residual voids in the goaf provided by the present invention.

[0021] Figure 4 It is a line graph of the width of mining-induced fissures at different depth positions of a longwall goaf and at different plane positions from the boundary of the goaf in a grouting method based on differentiated zoning of residual voids in the goaf provided by the present invention.

[0022] Figure 5 It is a curve diagram of the change of mining crack width at different depth positions of a longwall goaf and at different plane positions away from the boundary of the goaf in a grouting method based on differentiated zoning of residual voids in the goaf provided by the present invention.

[0023] Figure 6 It is a schematic plan view of the differentiated zoning of coal mine goaf areas in a grouting method based on differentiated zoning of residual voids in goaf areas provided by the present invention.

[0024] 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 areas provided by the present invention.

[0025] Figure 8 It is a structural schematic diagram of a grouting device based on differentiated zoning of residual voids in goaf areas provided by the present invention.

[0026] Fig. 9 It is a schematic diagram of the physical structure of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0027] The stability of coal mine goaf is an extremely complex issue. It is not only related to the geological mining conditions such as the depth, inclination, thickness of the mining body, the lithology, occurrence state, thickness, physical and mechanical properties of the overlying rock strata, geological structure, site topography, hydrogeological conditions, coal mining area, roof management methods, mining times and mining methods, but also closely related to the type, size and location of the upper load. The most common goaf forms formed by the underground cross-border mining of open-pit coal mines include longwall working face goaf, room-and-pillar goaf, independent shaft and tunnel, etc.; some underground coal mines with complex conditions may have many types 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.

[0028] Due to the existence of the articulated structure, the porosity and compaction degree of the boundary area and the middle part of the working face of the longwall mining method in underground coal mines are bound to be different. The tunnel / room-pillar mining method is to leave coal pillars of different shapes in the coal room. The coal pillars temporarily support the roof when mining the coal room, and the remaining coal pillars are recovered in a planned manner after the coal room is mined. According to the shape of the coal pillars, it is divided into block coal pillar room-pillar mining method and strip coal pillar room-pillar mining method. The tunnel / room-pillar mining method has the advantages of low equipment investment; mining and excavation can be achieved in one, short construction period, fast coal output; flexible equipment operation and fast relocation.

[0029] In the past few decades, due to the unreasonable industrial structure and in pursuit of quick benefits, many coal mines have used the tunnel / room-pillar mining method to quickly mine shallow coal seams, resulting in large areas of tunnel / room-pillar goaf with suspended roofs; as time went on, a series of disasters were triggered under the influence of water, air, coal seam group mining disturbance (adjacent coal seam mining activities), ground production activities (ground construction, ground equipment pressure and vibration, etc.).

[0030] At the same time, these lane-type / room-pillar goafs are scattered all over the place, of different sizes, shapes, and complex layers. In addition, due to incomplete, lost, or insufficient design data, the location and boundaries of many goafs cannot be determined. If open-pit mining is carried out in these areas, it will inevitably cause accidents such as goaf roof collapse, large equipment falling, or casualties. Therefore, it is necessary to reasonably determine the thickness of the safe anti-collapse coal rock pillar and the safe waterproof coal rock pillar, and complete the treatment of the underlying underground goaf before the open-pit coal mine reaches the limit thickness.

[0031] The essence of goaf safety management is to transfer stress concentration areas, ease the degree of stress concentration in the rock mass, and make the stress reach a new relative balance, so as to control and manage the ground pressure and ensure safe production in mines. The technical requirements for goaf safety management are high and difficult, and it has always been an important part of mine rock mechanics research. Depending on the different conditions of the ore deposit and mining technology, the technical methods for goaf safety management are also different. Research shows that no matter what technical method is used, it is to improve the stress distribution state of the surrounding rock, reduce stress concentration, prevent excessive deformation of the rock mass, and control the amplitude of rock movement, etc., and ultimately eliminate the hidden dangers of the goaf and avoid disasters to achieve safe production.

[0032] The main methods for safe management of goaf include the following: management of goaf by collapse of surrounding rock (i.e., caving method), management of goaf by filling method, support of goaf by permanent pillars, isolation and dredging of goaf. Each method has certain applicable conditions and limitations.

[0033] For example, the caving method for treating goafs requires the use of drilling equipment to drill into the goafs, and at the same time, it requires the installation of explosives at the designed position in a hole at a depth of about 100m. The installation and detonation difficulties are relatively large and not easy to achieve.

[0034] In the process of backfilling goaf treatment, drilling and grouting construction are often carried out directly on the surface, which is quite blind. No differentiated zoning is carried out according to the type of goaf and the residual spatial characteristics, and no targeted treatment and control technology is proposed.

[0035] In addition, in the existing technology, the zoning methods of "the design method of the zoning filling rate of the goaf area of ​​the comprehensive mining working face passing through the underlying empty tunnel", "the graded zoning management method of complex goaf" and "the zoning controlled filling continuous mining method of the isolation pillars in the underground goaf area" are to artificially divide the empty tunnel to be managed into several parts, and manage them in different areas and stages. This zoning segmentation technology cannot guide the management of complex and multi-type goaf areas; 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, and the safe mining and stripping operations of equipment and personnel in the open-pit mines cannot be guaranteed.

[0036] 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 does not have a scientific judgment formula or judgment standard for determining the non-compacted area. It only performs disorderly and unscientific grouting treatment; it does not conduct residual space and stability analysis on the pillar goaf, residual space and support strength and stability analysis on the residual shaft and tunnel, and does not differentiate the treatment technology of complex goaf for various mining processes, nor does it conduct process comparison or screening technology for goafs under various zoning conditions; it does not combine indoor experiments and put forward a scientific basis for the spacing setting of grouting boreholes. , the hole spacing is often determined based on construction experience; no precise control of slurry concentration and treatment process and grouting optimization technology are proposed according to the residual void characteristics, connectivity characteristics and partition characteristics of each goaf; no grouting fluidity assurance technology based on residual water detection and drainage is formulated for the treatment of underlying goaf in open-pit mines; the non-top connection problem affected by the slurry water separation rate is not considered, and no secondary slurry injection control top connection technology is proposed within the treatment area; no grouting effect detection and evaluation is carried out for goafs that have been treated with grouting filling, and a comprehensive analysis and evaluation from point to surface and from qualitative to quantitative cannot be achieved.

[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the 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.

[0038] Combine the following Figures 1 to 9 The present invention describes a grouting method and device based on differentiated zoning of residual voids in goaf areas.

[0039] Figure 1 Schematic diagram of a grouting method based on differential zoning of residual voids in goaf provided by the present invention, such as Figure 1 As shown, the method includes the following steps.

[0040] Step 101: design a plurality of first exploration holes at different plane positions of a longwall goaf of a coal mine, and design a plurality of second exploration holes at different plane positions of a pillar goaf of a coal mine.

[0041] 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 goafs to be treated (including longwall goafs and pillar goafs, etc.); design goaf survey plans based on the analysis results of basic geological mining data, and implement corresponding goaf survey work.

[0042] 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 boundary of the working face). The ground goaf exploration holes can be designed in combination with the mining engineering plan and the coal mining technology of the working face. The goaf exploration work can be 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 can be analyzed based on the current survey results of the goaf.

[0043] In the embodiment of the present invention, an example is taken to describe the design of four first exploration holes at different plane positions in a longwall goaf of a coal mine. Figure 2 Schematic diagram of the plan layout of longwall goaf exploration holes in a grouting method based on differential zoning of residual voids in goaf provided by the present invention, such as Figure 2 As shown. In a certain open-pit mine (in order to specifically illustrate a grouting method based on differential zoning of residual voids in goaf provided by the present invention, a certain open-pit coal mine is selected for the introduction of a specific embodiment, hereinafter referred to as the open-pit mine), a total of 4 first exploration holes are designed in the longwall goaf, namely K3, K4, K5 and ZK5 boreholes, and the distances of these 4 boreholes from the boundary of the goaf on the plane are 3m, 6m, 9m and 26.6m respectively.

[0044] In the pillar-type goaf of a coal mine, several (any number such as 4, 5 or 6) goaf exploration holes (i.e., the second exploration holes) can be designed at different plane positions (i.e., positions at different distances from the boundary of the working face). The ground goaf exploration holes can be designed in combination with the mining engineering plan and the coal mining technology of the working face. The goaf exploration work can be 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 can be analyzed based on the current survey results of the goaf.

[0045] In the embodiment of the present invention, an example is taken to describe the design of seven second exploration holes at different plane positions in a coal mine goaf. Figure 3 Schematic diagram of the plane layout of the exploration holes in the goaf area in the grouting method based on the differential zoning of residual voids in the goaf provided by the present invention, such as Figure 3 A total of 7 first exploration holes were designed in the open-pit mine goaf, including K1, K2 and K6 boreholes, ZK1, ZK2, ZK6 and ZK10 boreholes.

[0046] By designing multiple first exploration holes at different positions 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 positions in the pillar goaf of a coal mine, further exploration of the pillar goaf can be carried out to obtain the residual space characteristics.

[0047] Step 102: Based on the multiple first exploration holes, obtain the mining fissure width characteristics at different positions of the longwall goaf of the coal mine, and based on the multiple second exploration holes, obtain the residual space characteristics at different positions of the pillar goaf of the coal mine.

[0048] 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 on the plane 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 at different positions (3m, 6m, 9m and 26.6m) of the boundary correspond 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. Table 1 is a comparison table of formation damage detection conditions in the hole provided by the present invention, as shown in Table 1.

[0049] Table 1 Comparison of formation damage detection in the borehole

[0050] Figure 4 It is a line graph of the width of mining cracks at different depths of a longwall goaf and at different plane positions from the boundary of the goaf 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 at the hole depth of 89.0m, the width of the mining cracks 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 cracks 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.

[0051] In the embodiment of the present invention, the variation curve of the width of the mining crack at the hole depth of 129.7m in the longwall goaf is taken as an example for explanation. In this case, the curve equation of the width of the mining crack at different depths of the longwall goaf of the coal mine and at different plane positions from the boundary of the goaf can be obtained by fitting calculation using software (such as mathematical statistical analysis software MATLAB or simulation software, etc.) as follows:

[0052] in, Represents the single maximum crack width at different positions from the working surface boundary, x Indicates the distance to the boundary of the goaf.

[0053] Based on the above mining crack width curve equation, combined with Figure 4 The width of the mining cracks in the longwall goaf of the coal mine at a depth of 129.7m is shown in Figure 1. Figure 2 ) boundary position gradually increases and decreases, and the width of the mining cracks at the position of 129.7m deep in the longwall goaf area is plotted as the width of the mining cracks 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.

[0054] Figure 5 It is a graph of the variation of the width of mining cracks at different depths of a longwall goaf and at different plane positions from the boundary of the goaf in a grouting method based on the differentiated zoning of residual voids in the goaf provided by the present invention, such as Figure 5 As shown. Figure 5 In the figure, the black line indicates that 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 ) The red curve shows that the width of the mining cracks in the longwall goaf of the coal mine decreases with the increase of the distance from the boundary position. The red curve shows that at the hole depth of 129.7m, the width of the mining cracks in the longwall goaf of the coal mine increases with the distance from the 6039 working face (see Figure 2 ) The crack width variation curve where the distance from the boundary position gradually increases and decreases.

[0055] Similarly, the same method can also be used to obtain the corresponding mining crack width change curve of the longwall goaf of the coal mine at a hole depth of 89.0m, 107.4m or other positions.

[0056] 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 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 size, the smaller the residual pores in the longwall goaf (i.e. The smaller the value, the better the compaction of the longwall goaf. Based on the above compaction characteristics of the longwall goaf, the foundation can be laid for the differentiated zoning of the longwall goaf, that is, the longwall goaf can be scientifically divided, for example, into longwall compaction areas or longwall non-compaction areas.

[0057] In the embodiment of the present invention, seven second exploration holes are designed in the open-pit mine goaf, namely, K1, K2 and K6 boreholes and ZK1, ZK2, ZK6 and ZK10 boreholes (see Figure 3 ). At the same time, the mining engineering plan and working face operation procedures of the historical goaf were collected to analyze the distribution characteristics and support characteristics of the residual shafts and tunnels underground, and the stability of the residual shafts and tunnels was analyzed based on the support strength of the residual shafts and tunnels. According to the mining engineering plan and other data, the survey was carried out based on the above-mentioned 7 second exploration holes to understand the residual space characteristics of the pillar-type goaf, including coal seam mining conditions, residual pore volume parameters, and stability parameters.

[0058] Based on the drilling anomaly records of the exploration holes in the goaf area, the results of core drilling, and the comprehensive analysis combined with color borehole television and drilling characteristics, it can be found that there are still residual voids of 0.6~2.2m in the goaf with pillars. Specifically, ① The color borehole television detection of K1 borehole shows that there are still residual voids with a height of about 0.7~1.5m at the depth of 110.0~113.0; ② The color borehole television detection of K2 borehole shows that there are still residual voids with a height of about 0.6m at the depth of 106.0~106.6; ③ The K6 borehole cannot accurately measure the fracture parameters due to the serious wall breakage; ④ The ZK1 borehole deviates and no void is found; ⑤ The ZK2 borehole cannot accurately measure the fracture parameters due to the serious wall breakage; ⑥ The ZK6 borehole is located at the intersection of the goaf with pillars, and the residual void height is about 1.7~2m; ⑦ The ZK10 borehole has developed fractures and is seriously broken. If open-pit mining is carried out on the top of such residual cavities (especially when the thickness of the remaining safe coal and rock layer is small), the safety of machinery and personnel cannot be guaranteed.

[0059] According to the mining engineering plan and other information, in the open-pit mine pillar-type goaf area, the remaining tunnels involve area tunnels, working face recovery tunnels, connecting tunnels, exploration tunnels, pressure relief tunnels, etc., and the chambers involve parking lots, water storage tanks, chutes, coal chutes, connecting tunnels, refuge chambers, substations, material warehouses, etc.

[0060] In addition, the main tunnels of the 6 coal mining area within the scope of open-pit mining are generally built in the form of masonry. The 6 coal pillar goaf tunnels use I-beam trapezoidal sheds for tunnel support (with intervals of 0.8m), and the unrecovered I-beams remain underground; the fully-mechanized mining face drifts and mining area tunnels of the 6 coal lower layer use anchor cables, anchor rods and metal mesh for tunnel support (no concrete spraying); the 6 coal upper layer and working face drifts use I-beam trapezoidal sheds for tunnel support (the length and width of the residual goaf tunnels are 2.4m 2.4m section).

[0061] The cutting eyes and stop-mining line sides of the mining working faces of each longwall goaf are supported by "anchor rods + hanging nets", and the distance of strengthened support is 20~25m. Some working faces are supported by π-shaped long steel beams + single pillars; the coal chute is supported by masonry arches; the water tanks, substations and other chambers are supported by masonry arches. The support strengths and stability of various support methods are different.

[0062] According to the support strength and design strength records of each residual shaft and tunnel, the residual shaft and tunnel support and stability analysis is carried out. 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 and maintenance-free state; the working face mining tunnels, exploration tunnels, etc. can still be maintained for about 10 to 20 years in a natural and maintenance-free state. Based on the residual space characteristics of different positions in the above-mentioned pillar-type goaf area, the pillar-type goaf area can be scientifically divided, for example, into longwall independent shaft and tunnel areas or pillar mining areas.

[0063] 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.

[0064] 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, differentiated zoning is performed on the goaf of the coal mine.

[0065] Based on the working face layout and mining technology (continuous mining machine tunnel mining, room-and-pillar mining, longwall blasting and longwall comprehensive mining, etc.) of the underlying well workers' cross-boundary mining in the mining area, comprehensive goaf area survey results and mining support data, etc., the residual space in different goaf areas can be zoned.

[0066] For example, longwall goaf areas can be scientifically divided according to their compaction characteristics.

[0067] 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 worse the compaction of the longwall goaf; 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 better the compaction of the longwall goaf; 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.

[0068] 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.

[0069] For the pillar-type goaf areas with residual space characteristics such as drifts, large tunnels, permanent chambers and other non-collapsed spaces, they can be divided into longwall independent shaft and goaf areas; for the arched courtyard goaf areas in the pillar-type goaf areas, 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, and they can be divided into pillar mining areas.

[0070] As for the out-of-boundary mining areas, 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.

[0071] Figure 6 Schematic diagram of the differential partitioning of coal mine goaf in a grouting method based on the differential partitioning of residual voids in goaf provided by the present invention, such as Figure 6 In the embodiment of the present invention, based on the existing mining goaf exploration results, the coal mine goaf is divided into five types: Class I - long wall compaction area, Class II - long wall non-compaction area, Class III - long wall independent shaft and tunnel area, Class IV - pillar mining area and Class V - screening blank area.

[0072] The embodiment of the present invention performs differentiated zoning of coal mine goafs based on the mining fissure width characteristics at different positions of coal mine longwall goafs and the residual space characteristics at different positions of coal mine pillar goafs, 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 grouting management of goaf areas.

[0073] 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 in the coal mine goaf.

[0074] After the coal mine goaf is divided into different zones, the appropriate grouting process is selected for each zone to treat the coal mine goaf. The following is an example of goaf treatment in an open-pit mine.

[0075] 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, hydraulic fracturing of roof, roof blasting (carbon dioxide blasting, gas-producing agent blasting, explosive blasting for coal mines, etc.), residual coal pillar blasting, coal seam floor blasting disturbance, freezing of water-rich goaf, high-water / ultra-high-water material roof support and residual coal pillar reinforcement.

[0076] Based on the residual space characteristics and support characteristics of the goaf in each zone, a comprehensive analysis is conducted based on 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, and different grouting processes for each zone are selected to achieve scientific, reasonable and safe treatment of different zones in the goaf.

[0077] Table 2 is a summary table of the characteristics of various goaf management methods provided in the embodiments of the present invention, as shown in Table 2.

[0078] Table 2 Summary of characteristics of various goaf treatment methods

[0079] In the embodiment of the present invention, the goaf of the open-pit mine is relatively complex, and there are longwall comprehensive mechanized mining, longwall blasting mining and pillar mining with large changes in mining size (commonly known as arched courtyard). 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 strata of the coal roof of the open-pit mine 6 after treatment are required to have higher stability.

[0080] According to 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.

[0081] Based on the above embodiments, when the underlying goaf is relatively complex and it is difficult to achieve the treatment effect by only using 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 according to the characteristics of various goafs. Table 3 is a summary table of various goaf and residual shafts, tunnels and chambers treatment methods provided by the present invention, as shown in Table 3.

[0082] Table 3 Summary of treatment methods for various goafs and residual shafts and tunnels

[0083] The embodiment of the present invention is based on the results of differentiated zoning of open-pit mine goafs, namely, five types of Category I - longwall compaction area, Category II - longwall non-compaction area, Category III - longwall independent shaft and tunnel area, Category IV - pillar mining area and Category V - screening blank area. Different grouting processes for coal mine goafs are screened to determine different treatment processes for different zones of coal mine goafs. Based on each different treatment process, different grouting processes are determined, that is, differentiated grouting design is performed. For example, no grouting is required for Category I - longwall compaction area, but different grouting processes need to be designed for Category II - longwall non-compaction area, Category III - longwall independent shaft and tunnel area and Category IV - pillar mining area. For Category V screening blank area, exploration must be carried out first and then the grouting process is selected.

[0084] 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 in the coal mine goaf.

[0085] Step 105: 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.

[0086] According to the different grouting processes for different partitions of the coal mine goaf that have been determined, the required grouting material ratio experiments are carried out in the indoor laboratory to obtain the slurry fluidity data under different grouting material ratio conditions. Based on the slurry fluidity data, the grouting material ratio is optimized and designed to obtain suitable grouting materials or slurries. Finally, grouting materials or slurries with different ratios are used to grout different partitions of the coal mine goaf. The following is an example of the goaf management of the above-mentioned open-pit mine.

[0087] According to the purpose of the test, it is necessary to design laboratory tests for composite slurries with different material ratios. All composite slurries are tested for water separation rate, fluidity, consistency, wet density, compressive strength, stone body density, initial setting time, and other physical and mechanical properties to master the physical and mechanical properties of composite slurries under different material ratios and provide data support for differentiated grouting in each zone.

[0088] 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 19h, and under water curing conditions, the initial setting time is 34h. Combined with the actual needs of the project, the different properties of the grout under the test indicators of the composite grouting material are comprehensively considered.

[0089] Combined with the residual space characteristics and connectivity characteristics of each partition of the goaf, the slurry fluidity and slurry ratio of each partition are comprehensively determined based on the indoor test results, so as to realize the differentiated grouting scheme design in each partition. The following is an example of designing differentiated grouting processes for the five types of goafs, namely, 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.

[0090] (1) Class I longwall compaction zone

[0091] The Class I longwall compaction zone is mainly the middle area of ​​the longwall working face mining area. It has good compaction properties. Under the load of large ground equipment, the pores and cracks are gradually compacted. There is no risk of equipment suddenly tilting or collapsing into the goaf, and there is no risk of people falling into the goaf.

[0092] Grouting process design: Drilling survey is mainly used to verify the development of pores and fractures in this area. It is necessary to maintain survey and monitoring of this area, and determine through experiments or theoretical calculations that grouting can be temporarily suspended.

[0093] (2) Class II - Longwall non-compacted area

[0094] 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.

[0095] The boundary of the non-compacted area is scientifically determined: According to the curve equation of the mining crack width at different depths of the longwall goaf of the coal mine and at different plane positions from the boundary of the goaf, the maximum residual pore values ​​at different positions from the boundary of the working face under the geological mining conditions can be obtained. Under the geological mining conditions of the open-pit mine, the maximum single crack width allowed under the conditions of equipment load and allowable uneven sinking is 4cm (the cumulative crack height within the collapse zone under this numerical condition is about 0.3m). Substituting the above mining crack width curve equation, the boundary width D=12m at this position from the working face can be obtained.

[0096] 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 = 4:1:6:3, the slurry flow distance (i.e. effective diffusion distance) can be guaranteed to be 24.1cm; referring to relevant design specifications and combining with the actual goaf conditions, considering the geological mining conditions 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 24m.

[0097] (3) Category III - Longwall shaft area

[0098] 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 storage tanks, chutes, coal chutes, connecting tunnels, refuge chambers, substations, material warehouses, etc.) in Class III-longwall shaft areas 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".

[0099] 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 = 4:1:7:3 proportion, the slurry flow distance (i.e. effective diffusion distance) is 23.5cm; 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 27m.

[0100] (4) Category IV - Pillar mining area

[0101] According to the survey results of the pillar-type goaf obtained by ground drilling in combination with color borehole television and sonar scanning technology, although there is a certain range of roof collapse in the Class IV-pillar mining area, there are still voids larger 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 condition of wooden support, it is speculated that there are still voids with a height of about 2.2m.

[0102] 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 proportion, 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.

[0103] (5) Category V - Screening blank area

[0104] Class V-screening blank areas mainly include: 6029 working face, 6031 working face and 6028 south working face and other areas were mined by roadheaders, and the roadheader mining size was 4.0 2.7m; 6029, 6031 and the south working face of 6028 and other areas are first mined by tunnel boring machine, and then the top coal mining is carried out by drilling and blasting on both sides (arch courtyard); 601 tunnel and pillar mining area is mined by "arch courtyard" technology (collapse pits with a diameter of about 10m have appeared on the surface in some areas); 8 coal adopts exploration tunnel, branch tunnel and other technologies to recover other independent shafts and tunnels in the mining area.

[0105] 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 TV + sonar" comprehensive detection technology is first used to complete the advance detection of the goaf in this area; then the grouting process design of this area is carried out according to the detection results (slurry indoor laboratory test, slurry ratio selection, hole diameter and hole spacing, etc.).

[0106] The embodiment of the present invention is based on different grouting processes for different partitions in the coal mine goaf, and the required grouting material ratio experiments are carried out in an indoor laboratory to obtain suitable grouting materials or slurries for different partitions in the coal mine goaf, and differentiated grouting is performed on different partitions in the coal mine goaf, thereby ensuring that the grouting liquid can be quickly and effectively filled into the goaf, and the effective diffusion distance of the slurry in each grouting borehole is accurately controlled, thereby achieving accurate, effective, safe and reliable management of different partitions in the coal mine goaf.

[0107] 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 result 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 the 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.

[0108] Optionally, obtaining the mining fissure width characteristics at different positions of the longwall goaf of the coal mine based on the multiple first exploration holes 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; Based on the mining fissure width curve equation, the mining fissure width characteristics at different positions of the longwall goaf of the coal mine are determined.

[0109] Specifically, based on the hole depths, hole diameters and coring requirements of the plurality of first exploration holes, a current situation 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 multiple first exploration holes, a line graph of the width of mining cracks at different depths of the longwall goaf of the coal mine and at different plane positions from the goaf boundary is drawn; Based on the mining crack width line graph, the curve equation of the mining crack width at different depths of the longwall goaf of the coal mine and at different plane positions away from the goaf boundary is fitted. 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.

[0110] For example, 4 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 boreholes. The distances of these 4 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 ) at different positions (3m, 6m, 9m and 26.6m) of the boundary, 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, the line graph of the mining crack width at different depths of the longwall goaf and at different plane positions from the boundary of the goaf can be obtained (continue to see Figure 4 ).

[0111] Take the variation curve of the mining crack width at the hole depth of 129.7m in the longwall goaf as an example. In this case, the curve equation of the mining crack width at different depths of the longwall goaf and different plane positions from the goaf boundary can be obtained by fitting calculation using software (such as mathematical statistical analysis software MATLAB or simulation software, etc.) as follows:

[0112] in, Represents the single maximum crack width at different positions from the working surface boundary, x Indicates the distance to the boundary of the goaf.

[0113] Based on the above mining crack width curve equation, Figure 4The width of the mining cracks in the longwall goaf of the coal mine at a depth of 129.7m is shown in Figure 1. Figure 2 ) boundary position gradually increases and decreases, and the width of the mining cracks at the position of 129.7m deep in the longwall goaf area is plotted as the width of the mining cracks increases with the distance from the 6039 working face (see Figure 2 ) Curve of the change in the width of the mining crack as the distance from the boundary position gradually increases (see Figure 5 ).

[0114] Similarly, the same method can also be used to obtain the corresponding mining crack width change curve of the longwall goaf of the coal mine at a hole depth of 89.0m, 107.4m or other positions.

[0115] 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 boundary of the working face 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 size, the smaller the residual pores in the longwall goaf (i.e. The smaller the value, the better the compaction of the longwall goaf.

[0116] 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 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.

[0117] Optionally, obtaining the residual spatial features of different positions of the coal mine pillar goaf based on the multiple second exploration holes includes: Based on the hole depths, hole diameters and coring requirements of the multiple second exploration holes, a current situation survey is conducted on the coal mine pillar goaf area to obtain residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf area; wherein the residual pore volume parameters include the length, width and height of the residual goaf areas at different positions of the coal mine pillar goaf area; the stability parameters include the lithology and water accumulation properties of the residual goaf areas at different positions of the coal mine pillar goaf area; Based on the residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf area, the residual space characteristics at different positions of the coal mine pillar goaf area are determined.

[0118] Specifically, a plurality of second exploration holes are designed at different planar positions of the open-pit mine pillar-type goaf, and a current status survey of the coal mine pillar-type goaf is conducted based on the hole depths, hole diameters and coring requirements of the plurality of second exploration holes, 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 pillar-type goaf. At the same time, the mining engineering plan drawings and working face operation procedures of the historical goaf are collected, and the distribution characteristics and support characteristics of the residual shafts and tunnels underground 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 pillar-type goaf.

[0119] For example, seven second exploration holes were designed at different plane positions in the open-pit mine goaf (see Figure 3 ), namely K1, K2 and K6 boreholes, ZK1, ZK2, ZK6 and ZK10 boreholes. Based on the abnormal records of drilling in the exploration holes in the goaf area, the results of core drilling, and a comprehensive analysis combined with color borehole television and drilling characteristics, it can be found that there are still residual cavities of 0.6~2.2m in the goaf of the pillar type. Specifically, the following are included: ① The color borehole TV detection of K1 borehole shows that there are still residual voids with a height of about 0.7~1.5m at the depth of 110.0~113.0; ② The color borehole TV detection of K2 borehole shows that there are still residual voids with a height of about 0.6m at the depth of 106.0~106.6; ③ The K6 borehole cannot accurately measure the fracture parameters due to the serious wall fragmentation; ④ The ZK1 borehole deviates and no void area is found; ⑤ The ZK2 borehole cannot accurately measure the fracture parameters due to the serious wall fragmentation; ⑥ The ZK6 borehole is located at the intersection of the tunnel in the pillar goaf area, and the height of the residual void detected is about 1.7~2m; ⑦ The ZK10 borehole has developed fractures and is severely fragmented. If open-pit mining is carried out on the upper part of such residual voids (especially when the thickness of the remaining safe coal and rock layer is small), the safety of machinery and personnel will not be guaranteed.

[0120] According to mining engineering plan and other information, in the pillar-type goaf area of ​​open-pit mines, the types of residual tunnels often include area tunnels, working face recovery tunnels, connecting tunnels, exploration tunnels and pressure relief tunnels, and chambers often include parking lots, water storage tanks, chutes, coal chutes, connecting tunnels, refuge chambers, substations and material warehouses.

[0121] In addition, the main tunnels of the 6 coal mining area within the scope of open-pit mining are generally built in the form of masonry. The 6 coal pillar goaf tunnels use I-beam trapezoidal sheds for tunnel support (with intervals of 0.8m), and the unrecovered I-beams remain underground; the fully mechanized mining face drifts and mining area tunnels of the 6 coal lower layer use anchor cables, anchor rods and metal mesh for tunnel support (no concrete spraying); the 6 coal upper layer and working face drifts use I-beam trapezoidal sheds for tunnel support (the tunnel has 2.4 2.4m section).

[0122] The cutting eyes and stop-mining line sides of the mining working faces of each longwall goaf are supported by "anchor rods + hanging nets", and the distance of strengthened support is 20~25m. Some working faces are supported by π-shaped long steel beams + single pillars; the coal chute is supported by masonry arches; water storage, substation and other chambers are supported by masonry arches, and the support strengths of various support methods are different.

[0123] 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 (stratum 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 recovery tunnels, exploration tunnels, etc. can still be maintained for about 10 to 20 years in a natural maintenance-free state.

[0124] The embodiment of the present invention obtains the residual spatial characteristics of the pillar-type goaf area of ​​a coal mine based on multiple second exploration holes, reveals the residual spatial characteristics of the pillar-type goaf area from the perspectives of quantitative calculation and qualitative analysis, and further provides a scientific and reasonable basis for the division of different areas of the pillar-type goaf area.

[0125] 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: 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.

[0126] Specifically, based on the mining crack width characteristics at different positions of the longwall goaf area of ​​the coal mine and the residual space characteristics at different positions of the pillar goaf area of ​​the coal mine, the goaf area of ​​the coal mine is divided into at least two of the four types of longwall compaction area, longwall non-compaction area, longwall independent shaft and goaf area, and pillar mining area. In addition, the embodiment of the present invention can also scientifically divide more other areas according to the survey situation. For example, for areas that are still uncertain or have not been explored clearly, that is, it is still uncertain whether it is a goaf area or what kind of goaf area it is, it can also be divided into screening blank areas for further investigation later.

[0127] For example, longwall goaf areas can be scientifically divided according to their compaction characteristics.

[0128] 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 worse the compaction of the longwall goaf; 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 better the compaction of the longwall goaf; 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.

[0129] 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.

[0130] For the pillar-type goaf areas with residual space characteristics such as drifts, large tunnels, permanent chambers and other non-collapsed spaces, they can be divided into longwall independent shaft and goaf areas; for the arched courtyard goaf areas in the pillar-type goaf areas, 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, and they can be divided into pillar mining areas.

[0131] As for the out-of-boundary mining areas, due to the lack of drawings and materials, it is still uncertain whether there are goaf areas. They can also be divided into screening blank areas for further exploration.

[0132] 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 ).

[0133] The embodiment of the present invention divides the coal mine goaf into at least two of the four types of 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 positions of the coal mine longwall goaf area and the residual space characteristics at different positions of the coal mine lane pillar goaf area. In addition, for the cross-border mining area, since it is not yet certain whether there is a goaf area, it can also be divided into a screening blank area. Through the above-mentioned differentiated zoning, it can provide support for the subsequent differentiated grouting and effective management of such goaf areas.

[0134] Optionally, before performing differentiated grouting on different partitions in the goaf of the coal mine based on the different grouting processes for different partitions in the goaf of the coal mine, the method includes: Determine that water is accumulated in the goaf in different subareas of the goaf; Based on the water accumulation in the goaf, determining the water level or water height of the water accumulation in the goaf; Based on the water level or height of the water in the goaf, design a drainage scheme for different subareas of the goaf before grouting; Based on the drainage scheme, drainage construction is carried out in different sub-areas of the coal mine goaf.

[0135] 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, then based on the water accumulation in the goaf, the water level or water height of the water accumulation in the goaf is determined. 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.

[0136] 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.

[0137] 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 during the goaf grouting treatment process, the present invention uses the "electrical physical detection + drilling" comprehensive detection method to determine the water level or water height of the goaf in the goaf to be treated, and designs the 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 drainage hole under the pit and the ground drainage well, and finally performs drainage construction.

[0138] For example, in an open-pit mine, the scope of water accumulation in the goaf was initially determined through electrical physical detection, and then six ground boreholes were used to determine that the static water accumulation in the goaf was 2.04 million m 3 The water level is +330m. At the same time, scientific tests are carried out on the permeability and dynamic water replenishment capacity of the strata during the drilling process. Based on the detection results, the design adopts the open-pit mine with a drainage capacity of 800m 3 / h of drainage holes under the pit to allow for pre-drainage. After drainage is completed, grouting and filling treatment can be carried out.

[0139] 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 spaces that are larger or smaller), 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 uses color drilling television for detailed detection 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.

[0140] 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 open-pit mine goaf. After each borehole is completed, the drilling rig is first used to clean the hole wall. Then, a color drilling TV is used to complete the hole wall detection and 360° hole wall expansion diagram analysis of each hole to obtain the residual space data of the hole 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, on the basis of ensuring that the grouting liquid can be quickly and effectively filled into the goaf, the effective diffusion distance of the slurry in each grouting borehole is accurately controlled.

[0141] Since any composite slurry has the problem of water separation rate, after the equally spaced grouting drilling construction and grouting are completed, combined with the goaf area survey results and the mining project plan, at the intersection of main tunnels with strong diffusion capacity, the location where the tunnel inclination is large and the slurry is not easy to connect to the top, the location with large residual space in the goaf, the location with large terrain undulations and water is not easy to drain, or the location where the goaf survey is unclear, the goaf grouting drilling construction and grouting construction are designed and implemented again, and the space that has not been connected to the top after the previous grouting is replenished with slurry for the second time, so as to ensure slurry flow control and top connection.

[0142] In the embodiment of the present invention, based on different grouting processes for different sub-areas in the goaf of a coal mine, before performing differentiated grouting on different sub-areas in the goaf of a coal mine, it is first determined whether there is water accumulation in the goaf of different sub-areas in the goaf of the coal mine. 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.

[0143] Optionally, the present invention provides a grouting method based on differential zoning of residual voids in goaf, further comprising: 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 cavities in different sub-areas of the coal mine goaf, a strength of the grouting filling body in different sub-areas of the coal mine goaf, and a water level in different sub-areas of the coal mine goaf; Based on the detection results, a plan view of the slurry diffusion range is drawn.

[0144] Specifically, after grouting is completed in different zones of the coal mine goaf, the present invention also 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.

[0145] The embodiment of the present invention designs a comprehensive detection scheme of "drilling + color borehole television + rock mechanics test + comprehensive evaluation", and performs grouting effect detection and evaluation on the goaf that has been treated by grouting filling, so as to realize a comprehensive analysis and evaluation of the grouting effect from point to surface and from qualitative to quantitative, which specifically includes the following contents: (1) Filling rate detection: Design multiple boreholes to inspect the grouting effect in the goaf, analyze the core conditions of each layer in each detection hole, and use color borehole television to detect the slurry and cavity filling rate in each hole, and count the residual cavities. Combined with data such as ground equipment and dynamic loads, scientifically calculate the filling rate of the residual cavities in the goaf under the condition that the main equipment does not get stuck or overturn.

[0146] For example, in the open-pit mine type IV-pillar mining area, 27 grouting effect survey boreholes are designed to analyze the grouting effect filling rate; in the open-pit mine type III-longwall independent shaft and tunnel area, 34 grouting effect survey boreholes are designed to analyze the grouting effect filling rate; in the open-pit mine type II-longwall non-compacted area, 32 grouting effect survey boreholes are designed to analyze the grouting effect filling rate. Among them, the number of the above-mentioned grouting effect survey boreholes can be adjusted according to actual needs. Combined with the data of ground equipment and dynamic load, through scientific calculation, it can be obtained that when the filling rate of the residual voids in the above-mentioned different partitions of the goaf reaches more than 90%, the grouting effect is good. In this case, it can be guaranteed that the main equipment will not get stuck or overturn.

[0147] (2) Filling strength test: According to the coring results of the test hole, uniaxial compressive strength samples are prepared and tested for uniaxial compressive strength properties. Two groups of tests (4 to 6 samples in each group) are conducted for each hole; the strength of the grouting filling body is scientifically calculated in combination with data such as ground equipment and dynamic loads. The strength of the grouting filling body will gradually change with time, but the strength growth will usually slow down significantly after 28 days. Therefore, the embodiment of the present invention takes the calculation of the strength of the grouting filling body after 28 days as an example to illustrate the test effect.

[0148] For example, in the open-pit mine type IV-pillar mining area, 54 groups of slurry liquid uniaxial compressive strength property tests were conducted, in the open-pit mine type III-longwall independent shaft and tunnel area, 68 groups of slurry liquid uniaxial compressive strength property tests were conducted, and in the open-pit mine type II-longwall non-compacted area, 64 groups of slurry liquid uniaxial compressive strength property tests were conducted. Based on the equipment loads and dynamic loads such as ground wheel buckets, electric shovels, and dump trucks, the 28-day strength of the grouting filling body in the above-mentioned different partitions of the goaf can be obtained through scientific calculations.

[0149] (3) Water level detection: Water level detection can be used to obtain the water level change trend and water accumulation conditions in the goaf, providing a basis for management and prevention measures.

[0150] For example, in the open-pit mining category IV-pillar mining area, 27 grouting effect survey boreholes were designed to conduct water level detection and analysis, in the open-pit mining category III-long wall independent shaft and tunnel area, 34 grouting effect survey boreholes were designed to conduct water level detection and analysis, and in the open-pit mining category II-long wall non-compacted area, 32 grouting effect survey boreholes were designed to conduct water level detection and analysis. Through the comprehensive detection of "electrical physical detection + drilling", the water levels of the above-mentioned different sub-areas of the goaf are determined.

[0151] Based on the above embodiments, 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 Schematic diagram of slurry diffusion range in a grouting method based on differential zoning of residual voids in goaf provided by the present invention, such as Figure 7 shown. Figure 7 (a) in the figure shows the plane 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 above sentence indicates Figure 7 (a) in the figure is a schematic cross-sectional diagram of the slurry diffusion range, showing the slurry diffusion range from the side.

[0152] The embodiment of the present invention calculates and analyzes the stability of residual shafts and tunnels in different sub-zones of the goaf after treatment based on statistical analysis of grouting conditions in goaf areas, comparative analysis of drilling and borehole television observation data before and after grouting, grouting effect detection drilling analysis and core rock mechanics test results, combined with geological mining data, to achieve a comprehensive analysis and evaluation of the grouting effect of the goaf in open-pit mines from point to surface and from qualitative to quantitative, thereby further ensuring effective grouting and scientific treatment of the goaf in open-pit mines.

[0153] The following is a description of 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.

[0154] Based on any of the above embodiments, Figure 8 Schematic diagram of the structure of a grouting device based on differential partitioning 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 differential partitioning of residual voids in goaf, including a drilling module 801, a feature module 802, a partitioning module 803, a determination module 804 and a grouting module 805, wherein: The drilling module 801 is used to design a plurality of first exploration holes at different plane positions of the longwall goaf of a coal mine, and to design a plurality of second exploration holes at different plane positions of the pillar goaf of a coal mine; the feature module 802 is used to obtain the mining fissure width characteristics at different positions of the longwall goaf of a coal mine based on the plurality of first exploration holes, and to obtain the residual space characteristics at different positions of the pillar goaf of a coal mine based on the plurality of second exploration holes; the partitioning module 803 is used to perform differential partitioning of the coal mine goaf based on the mining fissure 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 for different partitions in the coal mine goaf based on the different grouting processes for different partitions in the coal mine goaf.

[0155] The present invention provides a grouting device based on differentiated zoning of residual voids in goafs. The present invention 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 result 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 the 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.

[0156] Fig. 9 An example of a physical structure diagram of an electronic device is shown in FIG. Fig. 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 through the communication bus 940. The processor 910 may call the logic instructions in the memory 930 to execute the grouting method based on the differential partitioning of the residual voids in the goaf, and the method includes: Designing a plurality of first exploration holes at different plane positions of the longwall goaf of the coal mine, and designing a plurality of second exploration holes at different plane positions of the pillar goaf of the coal mine; Based on the multiple first exploration holes, the mining crack width characteristics at different positions of the longwall goaf of the coal mine are obtained, and based on the multiple 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 goaf of the coal mine 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 in the coal mine goaf; 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.

[0157] In addition, the logic instructions in the above-mentioned memory 930 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0158] On the other hand, the present invention further provides a computer program product, the computer program product comprising a computer program, the computer program 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 the differential partitioning of residual voids in the goaf provided by the above methods, the method comprising: Designing a plurality of first exploration holes at different plane positions of the longwall goaf of the coal mine, and designing a plurality of second exploration holes at different plane positions of the pillar goaf of the coal mine; Based on the multiple first exploration holes, the mining crack width characteristics at different positions of the longwall goaf of the coal mine are obtained, and based on the multiple 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 goaf of the coal mine 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 in the coal mine goaf; 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.

[0159] In another aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the computer program is executed by a processor to execute the grouting method based on the differential zoning of residual voids in the goaf provided by the above methods, the method comprising: Designing a plurality of first exploration holes at different plane positions of the longwall goaf of the coal mine, and designing a plurality of second exploration holes at different plane positions of the pillar goaf of the coal mine; Based on the multiple first exploration holes, the mining crack width characteristics at different positions of the longwall goaf of the coal mine are obtained, and based on the multiple 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 goaf of the coal mine 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 in the coal mine goaf; 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.

[0160] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0161] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0162] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out 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 reverse 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.

[0163] It should also be noted that the terms "first", "second", "third", etc. in the present invention are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", and "third" are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more.

[0164] "Determine B based on A" in the embodiments of the present application means that the factor A should be considered when determining B. It is not limited to "B can be determined based on A alone", but 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. In addition, 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 another example, "When A meets the second condition, determine B", etc.; for another 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 for 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.

[0165] In the present invention, the term "plurality" refers to two or more than two, and other quantifiers are similar to them.

[0166] 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 embodiments of the present invention.

Claims

1. A grouting method based on differential zoning of residual voids in goaf, characterized in that: include: Designing a plurality of first exploration holes at different plane positions of the longwall goaf of the coal mine, and designing a plurality of second exploration holes at different plane positions of the pillar goaf of the coal mine; Based on the multiple first exploration holes, the mining crack width characteristics at different positions of the longwall goaf of the coal mine are obtained, and based on the multiple 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 goaf of the coal mine 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 in the coal mine goaf; 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.

2. The grouting method based on differentiated zoning of residual voids in goaf according to claim 1 is characterized in that: The method of obtaining the mining crack width characteristics at different positions of the longwall goaf of the coal mine based on the multiple first exploration holes 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; Based on the mining fissure width curve equation, the mining fissure width characteristics at different positions of the longwall goaf of the coal mine are determined.

3. The grouting method based on differential zoning of residual voids in goaf according to claim 1 is characterized in that: The method of obtaining 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 situation survey is conducted on the coal mine pillar goaf area to obtain residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf area; wherein the residual pore volume parameters include the length, width and height of the residual goaf areas at different positions of the coal mine pillar goaf area; the stability parameters include the lithology and water accumulation properties of the residual goaf areas at different positions of the coal mine pillar goaf area; Based on the residual pore volume parameters and stability parameters at different positions of the coal mine pillar goaf area, the residual space characteristics at different positions of the coal mine pillar goaf area are determined.

4. The grouting method based on differential zoning of residual voids in goaf according to claim 1 is characterized in that: The method of performing differentiated zoning 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 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.

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

6. The grouting method based on differential zoning of residual voids in goaf according to claim 1 is 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 cavities in different sub-areas of the coal mine goaf, a strength of the grouting filling body in different sub-areas of the coal mine goaf, and a water level in different sub-areas of the coal mine goaf; Based on the detection results, a plan view of the slurry diffusion range is drawn.

7. A grouting device based on differential 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 of a longwall goaf area of ​​a coal mine, and to design a plurality of second exploration holes at different plane positions of a pillar goaf area of ​​a coal mine; A feature module, for obtaining the mining crack width features at different positions of the longwall goaf of the coal mine based on the multiple first exploration holes, and for obtaining the residual space features at different positions of the pillar goaf of the coal mine based on the multiple second exploration holes; A partitioning module, used for performing differential 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 laneway pillar goaf; A determination module, for screening different grouting processes for coal mine goaf treatment based on the result of the differentiated zoning, and determining different grouting processes for different zones in the coal mine goaf; 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.

8. 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 6 is implemented.

9. 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 6 is implemented.

10. 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 6 is implemented.

Images