A superimposed goaf blasting filling method

Abstract

The present invention discloses a method for blasting and filling a superimposed goaf. By determining the superimposed range of a target goaf and a superimposed goaf in the vertical direction and setting explosives at the top plate position of the superimposed goaf within the superimposed range, a single blasting task can destroy the top plates of the target goaf and the superimposed goaf, thereby filling the two goafs and eliminating safety hazards.

Description

Technical Field

[0001] The invention relates to the technical field of goaf filling, and in particular to a superimposed goaf blasting filling method. Background Art

[0002] Goafs are "cavities" created beneath the surface by human excavation or natural geological movement. Their presence poses significant safety risks to mine operations, as personnel and equipment could fall into them and be injured. Blasting and caving is the most commonly used method for addressing goafs. This involves drilling downward blastholes on open-pit terraces and using blasting to forcibly collapse the goaf's roof to fill the area.

[0003] Because the blasting energy of traditional blast-caving methods primarily impacts the middle and upper portions of the goaf, they are not suitable for all goaf conditions. For example, if new goaf exists beneath the target goaf, blasting that goaf alone will have limited impact on the underlying goaf. This can lead to only partial collapse of the underlying goaf, leaving it incompletely filled, posing a significant safety hazard. To minimize the safety hazards posed by the underlying goaf, the current conventional treatment method requires a six-month quiescence period after blasting, with reduced mining and loading activities. During this period, the roof thickness and maximum load capacity of the underlying goaf must be continuously monitored to determine the appropriate excavator and mining truck. Furthermore, during the mining and loading process, 3D laser scanners and slope radars must be used to continuously monitor the movement of the blast pile 24 / 7. This mining and loading process takes at least two months. After mining and loading is complete, the underlying goaf must be monitored again, resulting in a total of 14 months for complete treatment. Consequently, conventional treatment methods consume a significant amount of manpower and time. Summary of the Invention

[0004] In view of the above problems, the present invention proposes a superimposed goaf blasting filling method, which mainly solves the problems of the background technology.

[0005] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0006] A superimposed goaf blasting filling method comprises the following steps:

[0007] Obtain the spatial distribution of the target goaf, and investigate the goaf below the target goaf. If there are goafs that partially overlap vertically below the target goaf, these goafs are defined as superimposed goafs.

[0008] Obtaining the spatial distribution of the superimposed goaf, determining the vertical superposition range of the target goaf and the superimposed goaf, and calculating the roof thickness of each point of the target goaf and the superimposed goaf within the superimposed range, as well as the spatial height of each point of the target goaf and the superimposed goaf;

[0009] For each point within the superposition range, the roof thickness of the target goaf is defined as L1, the roof thickness of the superimposed goaf is defined as L3, the spatial height of the target goaf is defined as L2, and the spatial height of each point in the superimposed goaf is defined as L4;

[0010] Several points are selected within the overlapping range as blasting points. For a single blasting point, the total length of L1, L2, L3 and L4 is calculated, and drilling is vertically downward toward the blasting point until the roof of the target goaf and the overlapping goaf is penetrated to form a through borehole. A pipe with a depth of the total length is placed into the borehole, and the pipe is filled with a first filler with a thickness of at least L4 but not more than L4+L3. Explosives are placed on the upper surface of the first filler, and then the second filler is continued to be filled on the upper surface of the explosives until the upper surface of the second filler reaches at least the middle of the roof of the target goaf. Finally, a detonating device is used to detonate the explosives in the pipe one by one.

[0011] In some embodiments, for the non-overlapping area of ​​the target goaf and the superimposed goaf, conventional drilling and charging operations are performed on the portion of the target goaf beyond the overlapping area and the portion of the superimposed goaf beyond the overlapping area.

[0012] In some embodiments, the pipe is a single-port PVC pipe with a closed lower end.

[0013] In some embodiments, an upper end port of the pipe is flush with an upper surface of a roof of the target goaf.

[0014] In some embodiments, the upper surface of the explosive does not exceed the upper surface of the roof of the superimposed goaf.

[0015] In some embodiments, the equivalent of the explosive located in the overlapping region is 1.5 times the conventional amount.

[0016] In some embodiments, the first filler and the second filler are both sand.

[0017] In some embodiments, a three-dimensional laser scanner is used to perform imaging simulation on the spatial distribution of the target goaf and the superimposed goaf to obtain the superimposed range.

[0018] The beneficial effects of the present invention are as follows: by determining the vertical overlapping range of the target goaf and the superimposed goaf, and setting explosives at the top plate position of the superimposed goaf within the overlapping range, a single blasting task can destroy the top plates of the target goaf and the superimposed goaf, thereby filling the two goafs and eliminating safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the structure of the target goaf and the superimposed goaf in an embodiment of the present invention;

[0020] Figure 2 Schematic diagram of the installation of explosives in an embodiment of the present invention.

[0021] Among them: 1-target goaf, 2-superimposed goaf, 3-drill hole, 4-pipeline, 5-first filling, 6-explosive, 7-second filling. DETAILED DESCRIPTION

[0022] To make the objectives, technical solutions, and advantages of the present invention more clear and distinct, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of the present invention.

[0023] This embodiment proposes a superimposed goaf blasting filling method, such as Figure 1 and 2 As shown, the following steps are included:

[0024] S1, obtain the spatial distribution of the target goaf 1, and check the goaf below the target goaf 1. If there is a goaf that partially overlaps vertically below the target goaf 1, it is defined as superimposed goaf 2.

[0025] S2, obtain the spatial distribution of the superimposed goaf 2, determine the superimposed range of the target goaf 1 and the superimposed goaf 2 in the vertical direction, calculate the roof thickness of each point of the target goaf 1 and the superimposed goaf 2 within the superimposed range, and the spatial height of each point of the target goaf 1 and the superimposed goaf 2.

[0026] For the spatial exploration tasks of S1 and S2, a three-dimensional laser scanner can be used to perform imaging simulation on the spatial distribution of the target goaf 1 and the superimposed goaf 2 to obtain the superimposed range.

[0027] S3, for each point within the superposition range, the roof thickness of the target goaf 1 is defined as L1, the roof thickness of the superimposed goaf 2 is defined as L3, the spatial height of the target goaf 1 is defined as L2, and the spatial height of each point in the superimposed goaf 2 is defined as L4;

[0028] S4. Select several points within the overlapping range as blasting points. For a single blasting point, calculate the total length of L1, L2, L3 and L4, drill vertically down to the blasting point until the roof of the target goaf 1 and the overlapping goaf 2 is drilled through to form a through borehole 3, and place a pipe 4 with a depth of the total length into the borehole 3. Fill the pipe 4 with a first filler 5 with a thickness of at least L4 but not more than L4+L3, place explosives 6 on the upper surface of the first filler 5, and then continue to fill the upper surface of the explosives 6 with the second filler 7 until the upper surface of the second filler 7 reaches at least the middle of the roof of the target goaf 1, and finally use a detonating device to detonate the explosives 6 in the pipe 4 one by one.

[0029] In S4, pipe 4 mainly plays a supporting role. After it is hoisted into borehole 3, it can reach the bottom of superimposed goaf 2 by its own weight and maintain a vertical state by its own rigidity and the fixation of two layers of roof. Preferably, pipe 4 is a single-end PVC pipe with a closed lower end. This design can avoid the loss of the first filler 5, explosive 6 and second filler 7, causing the position of explosive 6 to shift. The upper end of pipe 4 is flush with the upper surface of the roof of the target goaf 1. Taking borehole 3 (blasthole) with a hole diameter of 250mm as an example, a PVC pipe with a closed lower end 20-50mm smaller than the hole diameter of borehole 3 is inserted into the blasthole. Pipe 4 must ensure verticality, then fill the PVC pipe with fine sand to 1.5 meters above the bottom surface of the roof of the superimposed goaf 2, start loading explosives and detonators, stop loading 1.2 meters from the upper empty area, and start filling the blasthole. In actual application, the amount of explosives is adjusted according to the thickness of the interval between the two goafs.

[0030] More preferably, the upper surface of the explosive 6 does not exceed the upper surface of the roof of the overlapping goaf 2, ensuring that the blasting energy can first destroy the roof of the overlapping goaf 2, and rely on the remaining blasting energy to continue to destroy the roof of the target goaf 1. Based on the above technical solution, the equivalent of the explosive 6 in the overlapping area is 1.5 times the conventional amount. Taking the blasting task of a certain overlapping area as an example, its normal blasting hole network parameter is 6*7, and the unit consumption of explosives for blasting the interval layer between the two goafs is 0.8kg / m 3 To deal with this type of goaf, the hole network parameters need to be adjusted to 5m*5.5m, and the explosive consumption of the blasting layer between the two goafs is increased to 1.2kg / m 3 .

[0031] Optionally, the first filler 5 and the second filler 7 are both sand materials. Taking the filling task of the first filler 5 as an example, by obtaining the spatial height L4 of the superimposed goaf 2 and the cross-sectional area of ​​the pipeline 4 in advance, the volume of the first filler 5 to be injected can be calculated by multiplying the two.

[0032] The above steps S1-S4 describe the explosive design of the overlapping area in detail, and for the non-overlapping area of ​​the target goaf 1 and the superimposed goaf 2, conventional drilling and charging operations are performed on the portion of the target goaf 1 outside the overlapping area and the portion of the superimposed goaf 2 outside the overlapping area.

[0033] In this embodiment, by determining the vertical overlap range of the target goaf 1 and the superimposed goaf 2, and placing explosives at the roof of the superimposed goaf 2 within the overlap range, a single blasting mission can destroy the roofs of both the target goaf 1 and the superimposed goaf 2, thereby filling both goafs and eliminating safety hazards. Furthermore, compared to traditional methods for treating such superimposed goafs, this method can significantly shorten processing time and save explosive charge and a large amount of labor.

[0034] In this embodiment, only the blasting filling task of two overlapping goafs is described. It should be noted that three or more overlapping goafs can adopt this solution, and explosives can be loaded on the top plate of the bottom goaf.

[0035] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the essence of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A superimposed goaf blasting filling method, characterized in that: The following steps are involved: Obtain the spatial distribution of the target goaf, and investigate the goaf below the target goaf. If there are goafs that partially overlap vertically below the target goaf, these goafs are defined as superimposed goafs. Obtaining the spatial distribution of the superimposed goaf, determining the vertical superposition range of the target goaf and the superimposed goaf, and calculating the roof thickness of each point of the target goaf and the superimposed goaf within the superimposed range, as well as the spatial height of each point of the target goaf and the superimposed goaf; For each point within the superposition range, the roof thickness of the target goaf is defined as L1, the roof thickness of the superimposed goaf is defined as L3, the spatial height of the target goaf is defined as L2, and the spatial height of each point in the superimposed goaf is defined as L4; Several points are selected within the overlapping range as blasting points. For a single blasting point, the total length of L1, L2, L3 and L4 is calculated, and drilling is vertically downward toward the blasting point until the roof of the target goaf and the overlapping goaf is penetrated to form a through borehole. A pipe with a depth of the total length is placed into the borehole, and the pipe is filled with a first filler with a thickness of at least L4 but not more than L4+L3. Explosives are placed on the upper surface of the first filler, and then the second filler is continued to be filled on the upper surface of the explosives until the upper surface of the second filler reaches at least the middle of the roof of the target goaf. Finally, a detonating device is used to detonate the explosives in the pipe one by one.

2. The superimposed goaf blasting filling method according to claim 1, characterized in that: For the non-overlapping area of ​​the target goaf and the superimposed goaf, conventional drilling and charging operations are performed on the portion of the target goaf beyond the overlapping area and the portion of the superimposed goaf beyond the overlapping area.

3. The superimposed goaf blasting filling method according to claim 1, characterized in that: The pipeline is a single-end PVC pipe with a closed lower end.

4. The superimposed goaf blasting filling method according to claim 1, characterized in that: The upper port of the pipeline is flush with the upper surface of the target goaf roof.

5. The superimposed goaf blasting filling method according to claim 1, characterized in that: The upper surface of the explosive does not exceed the upper surface of the roof of the superimposed goaf.

6. The superimposed goaf blasting filling method according to claim 1, characterized in that: The equivalent of the explosives located in the overlapping area is 1.5 times the conventional amount.

7. The superimposed goaf blasting filling method according to claim 1, characterized in that: The first filler and the second filler are both sand materials.

8. The superimposed goaf blasting filling method according to claim 1, characterized in that: A three-dimensional laser scanner is used to perform imaging simulation on the spatial distribution of the target goaf and the superimposed goaf to obtain the superimposed range.

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