A mining damage reduction partition control method

Abstract

The application provides a mining damage reduction partition control method, which specifically comprises the following steps: determining the layer position, thickness and physical and mechanical parameters of a surface damage control layer according to geological exploration data of a mining area; determining the initial breaking span of the surface damage control layer according to the layer position, thickness and physical and mechanical parameters of the surface damage control layer; determining the distance between the midpoint of the initial breaking span of the surface damage control layer and a open-off cut; and starting grouting and filling of a goaf from the position of the open-off cut along the advancing direction of the working face, and the filling distance is the distance between the open-off cut and the midpoint of the initial breaking span of the surface damage control layer. The control method provided by the application reduces the subsidence gradient of the surface corresponding to the open-off cut and the stop mining line in the case of shallow-buried high-intensity mining, reduces the width and number of permanent ground fissures in the two areas, thereby reducing the degree of surface damage, and realizes efficient mining of underground coal resources while minimizing surface damage.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, specifically to a method for zoned control of mining-induced loss reduction. Background Technology

[0002] The existing overburden zoning isolation grouting and backfilling coal mining method mainly includes the following steps: dividing the mining area into several coal mining faces, leaving isolation coal pillars between the coal mining faces, determining the mining width of the coal mining face to be 100-200m while ensuring that the main key overburden layer does not break, and setting the width b of the isolation coal pillar to be 40-80m while ensuring that the isolation coal pillar has sufficient stability after grouting and backfilling mining of adjacent working faces; before mining the coal mining faces, constructing several sets of grouting boreholes sequentially on the surface above the coal mining faces towards the coal seam, each set of grouting boreholes being... One main grouting borehole and one auxiliary grouting borehole are used. The distance between two adjacent sets of grouting boreholes in the same coal mining face is 100-200m. All coal mining faces are mined one by one according to conventional mining technology. When the coal mining face is mined to 10-30m away from the main grouting borehole, fly ash slurry is injected into the delamination zone of the rock strata above the coal mining face through the main grouting borehole. When the coal mining face is mined to 10-30m away from the auxiliary grouting borehole, fly ash slurry is injected into the delamination zone of the rock strata above the coal mining face through the auxiliary grouting borehole. This cycle is repeated until the isolation grouting and filling of the mining area is completed.

[0003] In existing overburden zoning and grouting methods, zoning refers to isolating different separation zones by leaving coal pillars. In these methods, to prevent the main and critical overburden layers from fracturing, the working face width needs to be set at 100-200m. This increases the number of working face relocations, indirectly reducing production efficiency and contradicting the current concept of high-yield, high-efficiency, large-face mining. Furthermore, the coal pillars reduce the coal recovery rate. Summary of the Invention

[0004] The technical problem to be solved by this invention is to overcome the shortcomings of the prior art and provide a mining-induced damage reduction zoning control method. Under the condition of shallow-buried high-intensity mining, the subsidence slope of the surface corresponding to the opening cut and the stop line is reduced in zoning, and the width and number of permanent ground fissures in these two areas are reduced, thereby reducing the degree of surface damage and realizing efficient mining of underground coal resources while minimizing surface damage to the greatest extent.

[0005] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows:

[0006] A method for zoned control of mining-induced damage reduction specifically includes the following steps: S01. Determine the location, thickness, and physical and mechanical parameters of the surface damage control layer based on geological exploration data of the mining area. S02. Determine the initial fracture span of the surface damage control layer based on its location, thickness, and physical and mechanical parameters. S03. Determine the distance between the midpoint of the initial fracture span of the surface damage control layer and the cut-in hole. S04. Grouting and filling the goaf along the working face advancement direction, starting from the cut-in hole, with the filling distance being the distance between the cut-in hole and the midpoint of the initial fracture span of the surface damage control layer.

[0007] According to the mining-induced damage reduction zoning control method of the present invention, by accurately determining the stratum position, thickness and physical parameters of the surface damage control layer, the filling distance for grouting and filling the goaf starting from the cut-in position along the working face advancement direction is calculated. This ensures, in all aspects, a reduction in the subsidence slope of the soil and rock layers in the area near the cut-in, a reduction in the degree of damage to the aeolian sand layer and aquifer, and a reduction in the width and number of permanent ground fissures in these two areas. This reduces the degree of surface damage and achieves efficient mining of underground coal resources while minimizing surface damage to the greatest extent.

[0008] The above technical solution can be further improved as described below.

[0009] In a preferred embodiment of the mining-induced damage reduction zoning control method according to the present invention, the mechanical parameters include the tensile strength of the surface damage control layer and the overburden load of the surface damage control layer.

[0010] Based on the aforementioned physical and mechanical parameters, the initial fracture span of the surface damage control layer can be accurately calculated.

[0011] Specifically, in a preferred embodiment, in step S02, the initial fracture span of the surface damage control layer is... Where h is the thickness of the surface damage control layer, R t q represents the tensile strength of the surface damage control layer, and q represents the overburden load of the surface damage control layer.

[0012] Based on the above calculation formula, the initial fracture span of the surface damage control layer can be calculated quickly and accurately.

[0013] Specifically, in a preferred embodiment, in step S03, the distance between the midpoint of the initial fracture span of the surface damage control layer and the incision eye is... Where H is the distance between the surface damage control layer and the coal seam, and φ is the average fracture angle of the rock strata.

[0014] Based on the above calculation formula, the distance between the midpoint of the initial fracture span of the surface damage control layer and the incision eye can be calculated quickly and accurately.

[0015] Furthermore, in a preferred embodiment, in step S04, a filling method is adopted that varies in height from thick to thin.

[0016] By adopting the above-mentioned variable height filling method from thick to thin, it can effectively support the subsidence of the soil and rock layers in the area near the surface corresponding to the cut, thereby greatly reducing the subsidence slope of the soil and rock layers in this area.

[0017] Furthermore, in a preferred embodiment, the method of the present invention further includes step S05: starting grouting and filling in the goaf along the working face advancing direction at a predetermined distance from the working face stop line.

[0018] Through the above steps, we can comprehensively ensure the reduction of the subsidence slope of the soil and rock layers in the area near the surface corresponding to the cessation of mining, further reduce the damage to the aeolian sand layer and aquifer, reduce the width and number of permanent ground fissures in these two areas, thereby reducing the degree of surface damage and achieving efficient mining of underground coal resources while minimizing surface damage to the greatest extent.

[0019] Furthermore, in a preferred embodiment, in step S05, the filling distance is equal to the distance between the midpoint of the incision eye and the initial fracture span of the surface damage control layer.

[0020] The above-mentioned method of controlling the filling distance can effectively simplify the construction process for workers and improve construction efficiency.

[0021] Furthermore, in a preferred embodiment, in step S05, a filling method that varies in height from thin to thick is adopted.

[0022] By adopting the above-mentioned variable height filling method from thick to thin, it can effectively support the subsidence of the soil and rock layer in the area near the surface corresponding to the cessation of mining, thereby greatly reducing the subsidence slope of the soil and rock layer in this area.

[0023] Compared with existing technologies, the advantages of this invention are: in the case of shallow-buried high-intensity mining, the subsidence slope of the surface corresponding to the opening and stopping lines is reduced in sections, and the width and number of permanent ground fissures in these two areas are reduced, thereby reducing the degree of surface damage and achieving efficient mining of underground coal resources while minimizing surface damage. Attached Figure Description

[0024] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0025] Figure 1 This illustration shows the initial rupture of the unfilled surface damage control layer and subsequent surface subsidence.

[0026] Figure 2This illustration shows the situation of surface subsidence caused by repeated ruptures of the unfilled surface damage control layer;

[0027] Figure 3 The illustration shows the surface subsidence caused by multiple cyclical failures of the surface damage control layer after zonal variable height filling. Detailed Implementation

[0028] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments, but this does not limit the scope of protection of the present invention.

[0029] Figure 1 The illustration shows the initial surface subsidence caused by the initial rupture of the unfilled surface damage control layer. Figure 2 The illustration shows the situation of surface subsidence caused by repeated ruptures of the unfilled surface damage control layer. Figure 3 The illustration shows the surface subsidence caused by multiple cyclical failures of the surface damage control layer after zonal variable height filling.

[0030] like Figures 1 to 3 As shown, the mining-induced damage reduction zoning control method of this invention specifically includes the following steps: S01, determining the layer position, thickness h, and physical and mechanical parameters of the surface damage control layer 3 based on geological exploration data of the mining area. S02, determining the initial fracture span L of the surface damage control layer 3 based on the layer position, thickness h, and physical and mechanical parameters of the surface damage control layer 3. S03, determining the distance d between the midpoint of the initial fracture span L of the surface damage control layer 3 and the cutting hole. S04, grouting and filling the goaf 4 starting from the cutting hole position along the working face advancement direction, with the filling distance being the distance d between the cutting hole and the midpoint of the initial fracture span of the surface damage control layer 3.

[0031] According to the mining-induced damage reduction zoning control method of the present invention, by accurately determining the layer position, thickness and physical parameters of the surface damage control layer, the filling distance for grouting and filling the goaf area starting from the cut-in position along the working face advancement direction is calculated. This ensures that the subsidence slope of the soil and rock layers in the area near the surface corresponding to the cut-in is reduced in all aspects, the damage degree of aeolian sand layer 1 and aquifer 2 is reduced, and the width and number of permanent ground fissures in these two areas are reduced, thereby reducing the degree of surface damage and achieving efficient mining of underground coal resources while minimizing surface damage to the greatest extent.

[0032] like Figure 3 As shown, further, in this embodiment, in step S04, the filling body 5 is formed by a varying height filling method from thick to thin. This varying height filling method can effectively support the subsided portion of the soil and rock layers near the surface corresponding to the cut, thereby greatly reducing the subsidence slope of the soil and rock layers in that area.

[0033] Specifically, in this embodiment, the mechanical parameters include the tensile strength of the surface damage control layer 3 and the overburden load of the surface damage control layer 3. Based on these physical and mechanical parameters, the initial fracture span of the surface damage control layer can be accurately calculated. Specifically, in this embodiment, in step S02, the initial fracture span of the surface damage control layer 3... Where h is the thickness of the surface damage control layer, R t Let q represent the tensile strength of the surface damage control layer, and q represent the overburden load of the surface damage control layer. Based on the above calculation formula, the initial fracture span of the surface damage control layer can be calculated quickly and accurately.

[0034] like Figures 1 to 3 As shown, further, in this embodiment, in step S03, the distance between the midpoint of the initial fracture span of the surface damage control layer 3 and the incision eye is... Where H is the distance between the surface damage control layer 3 and the coal seam 6, and φ is the average fracture angle of the rock strata. Based on the above calculation formula, the distance between the midpoint of the initial fracture span of the surface damage control layer and the incision hole can be calculated quickly and accurately.

[0035] like Figure 3 As shown, further, in this embodiment, the method of the present invention also includes step S05: starting at a preset distance from the working face stop line, grouting and filling are carried out in the goaf area along the working face advancement direction to form a filling body 7. Through the above steps, the subsidence slope of the soil and rock layers in the area near the surface corresponding to the stop line can be reduced in all aspects, further reducing the damage to the aeolian sand layer and aquifer, reducing the width and number of permanent ground fissures in these two areas, thereby reducing the degree of surface damage and achieving efficient mining of underground coal resources while minimizing surface damage to the greatest extent.

[0036] Furthermore, in this embodiment, in step S05, a filling method with varying height from thin to thick is adopted. This varying height filling method effectively supports the subsided portion of the soil and rock layers near the surface corresponding to the cessation of mining, thereby significantly reducing the subsidence slope of the soil and rock layers in that area. Furthermore, in this embodiment, in step S05, the filling distance is equal to the distance d between the midpoint of the incision hole and the initial fracture span of the surface damage control layer. This method of controlling the filling distance effectively simplifies the construction process and improves construction efficiency.

[0037] Specifically, through Figure 3 and Figure 1 and Figure 2 A comparison shows that, after adopting the mining-induced damage reduction zoning control method of this embodiment, the surface subsidence situation after multiple cycles of surface damage control layer 3 is significantly better than that of the previous method. Figure 1 and Figure 2The surface subsidence situation caused by the failure of the unfilled surface damage control layer.

[0038] As can be seen from the above embodiments, the mining-induced damage reduction zoning control method of the present invention reduces the subsidence slope of the surface corresponding to the opening cut and the stop line in shallow-buried high-intensity mining, reduces the width and number of permanent ground fissures in these two areas, thereby reducing the degree of surface damage and achieving efficient mining of underground coal resources while minimizing surface damage to the greatest extent.

[0039] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A mining damage reduction partition control method, characterized by, Specifically comprising the following steps: S01, determining the layer position, thickness and physical and mechanical parameters of the surface damage control layer according to the geological exploration data of the mining area; S02, determining the initial breaking span of the surface damage control layer according to the layer position, thickness and physical and mechanical parameters of the surface damage control layer; S03, determining the distance between the midpoint of the initial breaking span of the surface damage control layer and the open-off cut; S04, starting from the open-off cut position, grouting and filling the goaf in the advancing direction of the working face, and the filling distance is the distance between the open-off cut and the midpoint of the initial breaking span of the surface damage control layer; In the step S02, the initial breaking span of the ground damage control layer ; wherein h is the thickness of the ground damage control layer, R t is the tensile strength of the ground damage control layer, and q is the overburden load of the ground damage control layer. In the step S03, the distance between the midpoint of the initial breaking span of the ground damage control layer and the open-off cut ; wherein, H is the distance between the ground damage control layer and the coal seam, and φ is the average breaking angle of the rock stratum.

2. The mining damage reduction partition control method according to claim 1, characterized by, The physical and mechanical parameters include the tensile strength of the surface damage control layer and the overburden load of the surface damage control layer.

3. The mining damage reduction partition control method according to claim 1 or 2, characterized by, In the step S04, the filling mode of thick to thin variable height is adopted.

4. The mining damage reduction partition control method according to claim 1 or 2, characterized by, Further comprising step S05, starting from a position at a preset distance from the working face stop line, grouting and filling the goaf in the advancing direction of the working face.

5. The mining damage reduction partition control method according to claim 4, characterized by, In the step S05, the filling distance is equal to the distance between the open-off cut and the midpoint of the initial breaking span of the surface damage control layer.

6. The mining damage reduction partition control method according to claim 4, characterized by, In the step S05, the filling mode of thin to thick variable height is adopted.

Images