A method for filling a mining void

Abstract

The application discloses a mining goaf filling roof-contacting method, which comprises the following steps: filling from an upper horizontal drift to a goaf, installing an anchor rod at the highest point of the roof of the upper horizontal rock drilling chamber after filling to the position of the upper horizontal floor, fixing a filling pipe and an exhaust dehydration pipe on the anchor rod, wherein the filling pipe comprises an outer sleeve pipe and an inner sleeve pipe, the upper end of the inner sleeve pipe is open, the lower end is half closed and half open, thereby forming a closed side and an open side, and the lumen of the outer sleeve pipe is divided into a first cavity and a second cavity; filling the goaf of the rock drilling chamber with filling material through the second cavity of the filling pipe; when filling to a set volume, disconnecting the second cavity from the connection of the filling pump, pressing into the first cavity through the filling pump, so that the upper end of the inner sleeve pipe extending out of the outer sleeve pipe is in contact with the top of the rock drilling chamber; connecting the second cavity with the grouting pump, continuing to fill the filling material, and until the exhaust dehydration pipe flows water outward, the roof-contacting is completed. Through the application, the roof can be completely contacted, and the safety hidden danger is reduced.

Description

Technical Field

[0001] This invention relates to the field of goaf filling technology, specifically, to a method for filling and connecting the roof of a mining goaf. Background Technology

[0002] In underground mines currently employing the backfilling method, the goaf formed after mining is cemented backfilled. The conventional backfilling method involves laying backfill pipes at the backfill retaining wall of the drilling chamber. However, since the backfill retaining wall is not located at the highest point of the goaf, the backfill pipe cannot fill the goaf above it. This results in the backfill material not properly connecting with the highest point of the drilling chamber. After backfilling, this often leads to floor subsidence during mining in the upper and middle sections, posing numerous safety hazards. Furthermore, if the backfill pipe sags during the backfilling connection process, it increases the distance between the pipe and the roof, also preventing a proper connection. How to effectively ensure proper backfilling connection is a challenging problem that needs to be solved. Summary of the Invention

[0003] To address the above problems, this application provides a method for backfilling and roof support in mining voids, comprising the following steps:

[0004] A lower filling retaining wall is built at the junction of the lower horizontal access road and the stope, and filling is carried out from the upper horizontal access road into the void area;

[0005] After filling to the upper horizontal floor level, install anchor bolts at the highest point of the roof of the upper horizontal drilling chamber, fixing one end of both the filling pipe and the venting and dewatering pipe to the anchor bolts, with the filling pipe opening extending to a predetermined position below the roof.

[0006] The filling tube includes an outer sleeve and an inner sleeve. The inner sleeve is fitted inside the end of the outer sleeve that faces the anchor rod. The upper end of the inner sleeve is open, while the lower end is half closed and half open, forming a closed side and an open side. The open side extends downward into a semi-circular insert tube, which is inserted into the second cavity.

[0007] The outer sleeve is divided into a first cavity and a second cavity along its tube axis. The first cavity corresponds to the closed side of the lower end of the inner sleeve, and the second cavity corresponds to the open side of the lower end of the inner sleeve.

[0008] A filling retaining wall is built at the junction of the upper horizontal access road and the stope. The second cavity of the filling pipe is connected to the injection pump, and filling material is injected into the empty area of ​​the drilling chamber through the second cavity of the filling pipe.

[0009] When the set volume is filled, disconnect the second cavity from the injection pump, connect the first cavity of the filling pipe to the injection pump, and pressurize the first cavity through the injection pump so that the upper end of the inner sleeve extends out of the outer sleeve and contacts the top of the rock drilling chamber.

[0010] Disconnect the first chamber from the grouting pump, connect the second chamber to the grouting pump, and continue grouting and filling until water flows out of the exhaust and dewatering pipe, at which point the connection is complete.

[0011] Optionally, the anchor bolts should be exposed no more than 0.5m above the upper horizontal drilling tunnel.

[0012] Optionally, the outer wall of the cannula is sealed to the second cavity by a sealing ring.

[0013] Optionally, the inner wall of the outer sleeve has a first annular protrusion and a second annular protrusion, and the outer wall of the inner sleeve has a third annular protrusion. In the initial state, the third annular protrusion is in contact with the first annular protrusion, and the first annular protrusion is located below the third annular protrusion.

[0014] Optionally, the length of the cannula is greater than the distance between the first annular protrusion and the second annular protrusion.

[0015] Optionally, a grout outlet is provided on the side wall of the inner casing. When the grouting pump pressurizes the first cavity, causing the upper end of the inner casing to extend out of the outer casing and contact the top of the rock drilling chamber, the grout outlet on the side wall of the inner casing is exposed.

[0016] This application uses anchor bolts fixed at the highest point of the roof to fix the filling pipe, which can ensure basic filling and roof connection. Even if the filling pipe falls during the filling process and cannot fully connect to the roof, the inner sleeve can be extended to contact the roof when filling is close to the roof, and filling can continue using the inner sleeve, thus achieving complete roof connection and reducing safety hazards. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a mining void area according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the filling tube according to an embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram of the annular protrusion in an embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of the inner sleeve extending from the outer sleeve according to an embodiment of the present invention. Figure 1 .

[0021] Figure 5 This is a schematic diagram of the inner sleeve extending from the outer sleeve according to an embodiment of the present invention. Figure 2 . Detailed Implementation

[0022] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] This embodiment discloses a method for backfilling and roof support in mining voids, including the following steps:

[0024] Step S1: After the mining of the stope is completed, a lower filling retaining wall 2 is built at the junction of the lower horizontal access road 1 and the stope, and filling is carried out from the upper horizontal access road 4 into the empty area.

[0025] In step S2, after filling to the upper horizontal floor level, a threaded steel bar with a diameter of 18mm and a length of 2m is used as an anchor rod 6 to fix the top plate of the upper horizontal drilling chamber 3 at the highest point of the top plate, with the anchor rod protruding 0.5m upwards. One end of the filling pipe 7 and the exhaust and dewatering pipe 8 are both fixed to the anchor rod 6, and the other end extends out of the upper filling retaining wall 5. The other end of the filling pipe 7 is connected to the injection pump. The opening of the filling pipe 7 extends to a predetermined position below the top plate.

[0026] Among them, such as Figure 2 , Figure 3 As shown, the filling tube 7 includes an outer sleeve 74 and an inner sleeve 73, with the inner sleeve 73 fitted inside the end of the outer sleeve 74 closest to the anchor rod 6. The inner sleeve 73 has an open upper end and a partially closed, partially open lower end, forming a closed side 734 and an open side 735. A semi-circular cross-section insertion tube 733 extends downward from the open side and is inserted into the second cavity 72. The outer wall of the insertion tube 733 and the second cavity 72 can be sealed with a sealing ring. A grout outlet hole is provided on the side wall of the inner sleeve 73.

[0027] The outer sleeve 74 is divided into two cavities along its axis: a first cavity 71 and a second cavity 72. The first cavity 71 corresponds to the closed lower end of the inner sleeve 73, and the second cavity 72 corresponds to the open lower end of the inner sleeve 73. Both the first cavity 71 and the second cavity 72 can be individually connected to the infusion pump.

[0028] The inner wall of the outer sleeve 74 has two annular protrusions, namely a first annular protrusion 741 and a second annular protrusion 742, and the outer wall of the inner sleeve 73 has a third annular protrusion 732. In the initial state, the third annular protrusion 732 is in contact with the first annular protrusion 741, with the first annular protrusion 741 located below the third annular protrusion 732, thereby restricting the downward movement of the inner sleeve 73. The length of the insertion tube 733 should be greater than the distance between the first annular protrusion 741 and the second annular protrusion 742, so that when the inner sleeve extends out of the outer sleeve, the first cavity 71 and the second cavity 72 remain separated.

[0029] Step S3: Construct a filling retaining wall 5 at the junction of the upper horizontal access road 4 and the stope. Connect the second cavity 72 of the filling pipe 7 to the injection pump, and inject filling material into the empty area of ​​the drilling chamber through the second cavity 72 of the filling pipe 7. When the injection pump injects filling material through the second cavity 72, the filling material can flow into the empty area of ​​the drilling chamber through the second cavity and the opening side of the inner sleeve.

[0030] In step S4, when the set volume is reached, the required amount of filling material to fill to the pipe opening height can be roughly estimated based on the preset position of the filling pipe 7 opening. When the amount of filling material consumed reaches the required amount, it indicates that the filling has approximately reached the pipe opening height. At this time, disconnect the connection between the second cavity 72 and the injection pump, and connect the first cavity 71 of the filling pipe 7 to the injection pump. Pressurize the first cavity 71 through the injection pump. The pressure acts on the closed side of the inner sleeve. When the pressure is high enough, the inner sleeve 73 will inevitably move upward, causing the inner sleeve 73 to extend upward beyond the outer sleeve 74 until the third annular protrusion 732 passes the second annular protrusion 742, at which point the pressurization stops. At this time, the inner sleeve 73 extends beyond the outer sleeve 74, and the upper end of the inner sleeve contacts the top of the drilling chamber, exposing the grout outlet on the side wall of the inner sleeve.

[0031] During the filling process, due to the vibration transmitted from the injection pump to the filling pipe, as well as the gravity of the filling pipe and filling material, the filling pipe may sag slightly, or even tilt slightly. This prevents the filling pipe from achieving a complete connection with the roof. In this embodiment, when filling near the roof slab, the inner sleeve extends from the outer sleeve, allowing the inner sleeve's opening to contact the roof slab. The grout outlet on the side wall of the inner sleeve is exposed outside the outer sleeve, allowing filling to continue through the grout outlet. This complete connection with the roof is achieved through the filling of the inner sleeve.

[0032] Of course, if the filling pipe does not fall at all, the opening of the filling pipe will always be at the top plate, and the inner sleeve of this application will not be pushed out, nor will it have any impact on the top.

[0033] like Figure 4This is a schematic diagram illustrating how, when the filling tube has sagged slightly, the inner sleeve 73 extends out from the outer sleeve 74, and filling is performed using the inner sleeve. (See diagram below.) Figure 5 This is a schematic diagram showing that the filling tube is slightly tilted, with the inner sleeve 73 extending out of the outer sleeve 74, and filling is carried out using the inner sleeve.

[0034] Step S5: Disconnect the first chamber 71 from the grouting pump, connect the second chamber 72 to the grouting pump, and continue grouting and filling until water flows out of the exhaust and dewatering pipe 8, at which point the connection is complete.

[0035] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications are all within the protection scope of the claims of the present invention.

Claims

1. A method for backfilling and roof support in mining voids, characterized in that, Includes the following steps: A lower filling retaining wall is built at the junction of the lower horizontal access road and the stope, and filling is carried out from the upper horizontal access road into the void area; After filling to the upper horizontal floor level, install anchor bolts at the highest point of the roof of the upper horizontal drilling chamber, fixing one end of both the filling pipe and the venting and dewatering pipe to the anchor bolts, with the filling pipe opening extending to a predetermined position below the roof. The filling tube includes an outer sleeve and an inner sleeve. The inner sleeve is fitted inside the end of the outer sleeve that faces the anchor rod. The upper end of the inner sleeve is open, while the lower end is half closed and half open, forming a closed side and an open side. The open side extends downward into a semi-circular insert tube, which is inserted into the second cavity. The outer sleeve is divided into a first cavity and a second cavity along its tube axis. The first cavity corresponds to the closed side of the lower end of the inner sleeve, and the second cavity corresponds to the open side of the lower end of the inner sleeve. A filling retaining wall is built at the junction of the upper horizontal access road and the stope. The second cavity of the filling pipe is connected to the injection pump, and filling material is injected into the empty area of ​​the drilling chamber through the second cavity of the filling pipe. When the set volume is filled, disconnect the second cavity from the injection pump, connect the first cavity of the filling pipe to the injection pump, and pressurize the first cavity through the injection pump so that the upper end of the inner sleeve extends out of the outer sleeve and contacts the top of the rock drilling chamber. Disconnect the first chamber from the grouting pump, connect the second chamber to the grouting pump, and continue grouting and filling until water flows out of the exhaust and dewatering pipe, at which point the connection is complete.

2. The method for backfilling and roof support in mining voids according to claim 1, characterized in that, The exposed length of the anchor bolt outside the upper horizontal rock drilling tunnel shall not exceed 0.5m.

3. The method for backfilling and roof support in mining voids according to claim 1, characterized in that, The outer wall of the cannula is sealed to the second cavity by a sealing ring.

4. The method for backfilling and roof support in mining voids according to claim 1, characterized in that, The inner wall of the outer sleeve has a first annular protrusion and a second annular protrusion, and the outer wall of the inner sleeve has a third annular protrusion. In the initial state, the third annular protrusion is in contact with the first annular protrusion, and the first annular protrusion is located below the third annular protrusion.

5. The method for backfilling and roof support in mining voids according to claim 4, characterized in that, The length of the cannula is greater than the distance between the first annular protrusion and the second annular protrusion.

6. The method for backfilling and roof connection of mining voids according to claim 1, characterized in that, A grout outlet is also provided on the side wall of the inner casing. When the grouting pump pressurizes the first cavity, causing the upper end of the inner casing to extend out of the outer casing and contact the top of the rock drilling chamber, the grout outlet on the side wall of the inner casing is exposed.

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