Working face roof fall treatment method

Abstract

The application provides a working face roof fall treatment method, comprising the following steps: drilling a first reinforcing hole to the coal seam top surface of a coal seam working area by a ground; lowering a first reinforcing rope into the first reinforcing hole by the ground; and respectively fastening two ends of the first reinforcing rope which are out of the ground and the coal seam top surface. The working face roof fall treatment method solves the problem of safety risk in the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal mining roof prevention and treatment, in particular to a working face roof fall treatment method. BACKGROUND

[0002] With the development of economic society and the continuous improvement of people's living standards, the demand for coal is increasing, especially in coal resource-rich areas. In order to better recover coal resources, combined with the continuous improvement of the level of domestic coal equipment, many coal mines have arranged more super-large mining height fully mechanized working faces according to the thickness of the coal seam.

[0003] However, due to the large mining height of the super-large mining height fully mechanized working face, the mine pressure appears generally strong, and the probability of large-scale roof fall accidents is high, which has a serious impact on safety production. Under normal circumstances, the fully mechanized working face roof fall accident is generally treated by anchor rod, anchor cable combined support, and advanced pull-out support, but for the super-large mining fully mechanized working face, due to the large mining height, which can reach more than 8m, the anchor rod, anchor cable combined support measure is very inconvenient to construct, and the effect is not obvious, and there is a safety risk of personnel falling. SUMMARY

[0004] The main purpose of the present application is to provide a working face roof fall treatment method to solve the problem of safety risk in the prior art working face roof fall treatment method.

[0005] In order to achieve the above-mentioned purpose, the present application provides a working face roof fall treatment method, comprising: drilling a first reinforcing hole from the ground to the coal seam top surface of the coal seam working area; lowering a first reinforcing rope into the first reinforcing hole from the ground; and fastening the two ends of the first reinforcing rope that protrude out of the ground and the coal seam top surface, respectively.

[0006] Further, the method of fastening the end of the first reinforcing rope that protrudes out of the ground comprises: installing a first lock and a first tray on the end of the first reinforcing rope that protrudes out of the ground, the first reinforcing rope is arranged on the first tray, and the first lock is located on the side of the first tray away from the ground and is locked with the first reinforcing rope.

[0007] Further, the method of drilling the first reinforcing hole comprises: drilling a row of first reinforcing holes along the width direction of the coal seam working area, the row of first reinforcing holes comprising a plurality of pairs of first reinforcing holes.

[0008] Further, the method for fastening the end of the first reinforcing rope extending out of the coal seam roof surface comprises: passing the first reinforcing rope in the pair of two first reinforcing holes through a support plate, the support plate being located on the side of the coal seam roof surface away from the ground; and installing a second lock and a second tray on the end of the first reinforcing rope extending out of the support plate, the first reinforcing rope being passed through the second tray, and the second lock being located on the side of the second tray away from the support plate and being locked with the first reinforcing rope.

[0009] Further, the working face roof falling processing method further comprises: repeating the steps of drilling the first reinforcing hole to fastening the first reinforcing rope along the advancing direction of the coal seam working face as the coal seam working face advances forward until the height of the falling area above the coal seam roof surface is lower than 2m.

[0010] Further, when the height of the falling area above the coal seam roof surface is lower than 2m, the working face roof falling processing method further comprises: drilling a second reinforcing hole and a third reinforcing hole from the coal seam roof surface to the falling area; laying a first protective net on the coal seam roof surface; and inserting a first anchor rod into the second reinforcing hole through the first protective net, and inserting an anchor cable into the third reinforcing hole.

[0011] Further, the third reinforcing hole is a plurality of third reinforcing holes arranged in rows, and the method for inserting the anchor cable into the third reinforcing hole comprises: passing the anchor cable in each of the plurality of third reinforcing holes in the row through the same connecting steel belt.

[0012] Further, when the height of the falling area above the coal seam roof surface is lower than 2m, the working face roof falling processing method further comprises: laying a second protective net on the coal seam working face, and drilling a second anchor rod into the coal seam working face through the second protective net.

[0013] Further, before drilling the first reinforcing hole, the working face roof falling processing method further comprises: drilling a first protective hole from the coal seam working face obliquely upward and to the falling area located above the coal seam working face; and injecting a protective material into the first protective hole until the protective material flows out from the gap communicating with the first protective hole.

[0014] Further, the working face roof falling processing method further comprises: repeating the steps of drilling the first protective hole to injecting the protective material into the first protective hole along the advancing direction of the coal seam working face as the coal seam working face advances forward.

[0015] Further, before drilling the first reinforcing hole, the working face roof falling processing method further comprises: drilling a second protective hole from the coal seam working face along the advancing direction of the coal seam working face; and injecting a protective material into the second protective hole until the protective material flows out from the gap communicating with the second protective hole.

[0016] Further, the roof fall treatment method of the coal mining face further comprises: repeating the steps of drilling the second protective hole to injecting the protective material into the second protective hole along the advancing direction of the coal mining face as the coal mining face advances.

[0017] The roof fall treatment method of the coal mining face in the present application adopts drilling a hole (a first reinforcing hole) from the ground to the coal seam roof of the coal mining area, threading a steel wire rope (a first reinforcing rope) in the first reinforcing hole, and fastening the two ends of the first reinforcing rope that extend out of the ground and the coal seam roof, thereby preventing the broken roof from continuing to fall, providing a relatively safe working environment for the workers of the coal mining face, overcoming the disadvantages of the high falling height and the inability to use the traditional roof fall treatment method of combined support of anchor rods and anchor cables, and thereby solving the problem of safety risks in the existing roof fall treatment method of the coal mining face. BRIEF DESCRIPTION OF DRAWINGS

[0018] The drawings accompanying the specification of this application form a part thereof, serve to provide further understanding of the application, and together with the description of the exemplary embodiments of the application given below, make an explanation of the application complete, and are not intended to limit the application unduly. In the drawings:

[0019] Figure 1 A top view of an embodiment of a fully mechanized coal mining area to which the roof fall treatment method of the coal mining face according to the present application is applied is shown;

[0020] Figure 2 A cross-sectional view of the fully mechanized coal mining area in Figure 1 is shown;

[0021] Figure 3 A cross-sectional view of the fully mechanized coal mining area in Figure 1 is shown;

[0022] Figure 4 A structural schematic diagram of the fully mechanized coal mining area to which the roof fall treatment method according to the present application is applied when the falling height of the falling area of the fully mechanized coal mining area is less than 2m is shown;

[0023] Figure 5 A bottom view of the fully mechanized coal mining area in Figure 4 is shown;

[0024] Figure 6 A side view of the fully mechanized coal mining area in Figure 4 is shown; and

[0025] Figure 7 A flowchart of an embodiment of the roof fall treatment method of the coal mining face according to the present application is shown.

[0026] Among the above drawings, the following reference signs are included:

[0027] 1, coal seam working face; 2, support plate; 3, second protective hole; 4, first reinforcing rope; 51, first lock; 52, second lock; 61, first tray; 62, second tray; 7, first protective hole; 8, coal seam top surface; 9, ground; 10, coal seam working area; 11, auxiliary transportation gate; 12, rubber transportation gate; 13, support; 14, crack; 15, anchor cable; 16, first anchor rod; 17, first protective net; 18, second anchor rod; 19, second protective net; 20, wedge-shaped wooden tray; 21, wooden tray; 22, connecting steel belt. DETAILED DESCRIPTION

[0028] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0029] The present application provides a working face roof fall treatment method, please refer to Figures 1 to 7 The working face roof fall treatment method includes: drilling a first reinforcing hole from the ground 9 to the coal seam top surface 8 of the coal seam working area 10; lowering a first reinforcing rope 4 into the first reinforcing hole from the ground 9; and respectively fastening the two ends of the first reinforcing rope 4 that extend out of the ground and the coal seam top surface 8.

[0030] The working face roof fall treatment method in the present application adopts drilling a hole (first reinforcing hole) from the ground to the coal seam top surface 8 of the coal seam working area 10, threading a steel wire rope (first reinforcing rope 4) in the first reinforcing hole, and respectively fastening the two ends of the first reinforcing rope 4 that extend out of the ground and the coal seam top surface 8, thereby preventing the broken roof from continuing to fall, and providing a relatively safe working environment for the working face operators, overcoming the drawbacks that the traditional roof fall treatment anchor rod and anchor cable combined support method cannot be used due to the high falling height, thereby solving the problem of safety risk existing in the working face roof fall treatment method in the prior art.

[0031] In the present embodiment, the method for fastening the end of the first reinforcing rope 4 that extends out of the ground includes: installing a first lock 51 and a first tray 61 on the end of the first reinforcing rope 4 that extends out of the ground, threading the first reinforcing rope 4 on the first tray 61, and locating the first lock 51 on the side of the first tray 61 away from the ground and in locking connection with the first reinforcing rope 4.

[0032] As shown in Figure 1 and Figure 2 The method for drilling the first reinforcing hole includes: drilling a row of first reinforcing holes along the width direction of the coal seam working area 10, and the row of first reinforcing holes includes a plurality of pairs of first reinforcing holes. Specifically, the width direction of the coal seam working area 10 is the A-A direction in Figure 1 .

[0033] Specifically, the method for fastening the end of the first reinforcing rope 4 extending out of the coal seam roof 8 includes: passing the first reinforcing rope 4 through the support plate 2 located on the side of the coal seam roof 8 away from the ground 9; and installing the second lock 52 and the second tray 62 on the end of the first reinforcing rope 4 extending out of the support plate 2, the first reinforcing rope 4 being arranged on the second tray 62, and the second lock 52 being located on the side of the second tray 62 away from the support plate 2 and being locked with the first reinforcing rope 4. By suspending the steel plate (the support plate 2) at the lower end of the steel wire rope at the working face position, the steel plate is tightly attached to the caving roof (the coal seam roof 8) after fastening.

[0034] In the embodiment, the working face roof fall processing method further includes: repeating the steps of drilling the first reinforcing hole and fastening the first reinforcing rope 4 along the advancing direction of the coal seam working face 1 until the height of the caving area above the coal seam roof 8 is lower than 2 m as the coal seam working face 1 advances. Specifically, a row of first reinforcing holes is processed each time the coal seam working face 1 advances, so that the first reinforcing ropes 4 can be installed row by row.

[0035] When the height of the caving area above the coal seam roof 8 is higher than 2 m, the caving area is reinforced by drilling the first reinforcing hole from the ground to the coal seam roof 8; and when the height of the caving area above the coal seam roof 8 is lower than 2 m, the caving area is reinforced by drilling the second reinforcing hole and the third reinforcing hole from the coal seam roof 8 to the caving area.

[0036] Specifically, as shown in Figures 4 to 6 When the height of the caving area above the coal seam roof 8 is lower than 2 m, the working face roof fall processing method further includes: drilling the second reinforcing hole and the third reinforcing hole from the coal seam roof 8 to the caving area; laying the first protective net 17 on the coal seam roof 8; and inserting the first anchor rod 16 into the second reinforcing hole and the anchor cable 15 into the third reinforcing hole through the first protective net 17.

[0037] In order to improve the reinforcing effect, as shown in Figure 5 The third reinforcing hole is a plurality of third reinforcing holes arranged in rows, and the method for inserting the anchor cable 15 into the third reinforcing hole includes: passing the anchor cable 15 in each of the plurality of third reinforcing holes in each row of the third reinforcing holes through the same connecting steel belt 22.

[0038] As shown in Figure 6 When the height of the caving area above the coal seam roof 8 is lower than 2 m, the working face roof fall processing method further includes: laying the second protective net 19 on the coal seam working face 1 and driving the second anchor rod 18 into the coal seam working face 1 through the second protective net 19.

[0039] The second anchor rod 18 is in multiple rows, and the multiple rows of second anchor rods 18 are spaced apart in the vertical direction. The uppermost row of second anchor rods 18 uses 400*200*(30-70)mm wedge-shaped wood pallets 20, and the middle three rows use wood pallets 21 with a size of 400*200*50mm.

[0040] In the embodiment, as shown in Figure 3 Before drilling the first reinforcing hole, the working face roof fall treatment method further comprises: drilling the first protective hole 7 upwardly and upwardly from the coal seam working face 1 to the caving area located thereon; and injecting the protective material into the first protective hole 7 until the protective material flows out from the gap (crack 14) communicating with the first protective hole 7. Preferably, the included angle between the center line of the first protective hole 7 and the horizontal plane is 15°.

[0041] In order to improve the protection effect, the working face roof fall treatment method further comprises: repeating the steps of drilling the first protective hole 7 to injecting the protective material into the first protective hole 7 along the advancing direction of the coal seam working face 1 as the coal seam working face 1 advances forward.

[0042] In the embodiment, as shown in Figure 3 Before drilling the first reinforcing hole, the working face roof fall treatment method further comprises: drilling the second protective hole 3 along the advancing direction of the coal seam working face 1 and from the coal seam working face 1; and injecting the protective material into the second protective hole 3 until the protective material flows out from the gap communicating with the second protective hole 3.

[0043] In order to improve the protection effect, the working face roof fall treatment method further comprises: repeating the steps of drilling the second protective hole 3 to injecting the protective material into the second protective hole 3 along the advancing direction of the coal seam working face 1 as the coal seam working face 1 advances forward.

[0044] The working face roof fall treatment method in the present application is a fully mechanized working face roof fall treatment method for a super-large mining height and shallow depth coal mine, as shown in Figure 7 The specific steps include:

[0045] The roof fall reason is analyzed to provide a basis for subsequent scientific roof fall treatment method.

[0046] The surrounding rock of the consolidated roof is prevented from continuing to fall, and the specific method is: drilling a hole in the roof and injecting a high polymer material (protective material) until it flows out in the coal wall gap.

[0047] With the advancing of the working face, the drilling and high polymer material injection operation in the roof are repeated until the caving roof is completely controlled.

[0048] The surrounding rock of the consolidated working face coal wall is prevented from falling, which causes the roof to fall, and the specific method is: drilling a hole in the working face coal wall and injecting a high polymer material until it flows out in the coal wall gap.

[0049] With the working face advancing forward, the drilling and high polymer material injection operation is repeated to the coal wall until the coal wall is complete and the fully caving roof is completely controlled.

[0050] In order to better and faster control the high caving area roof, the working face position is measured from the surface and a drilling hole is drilled to the working face, and two drilling holes (first reinforcing holes) are required to be symmetrically drilled at every certain distance interval, and the drilling hole spacing is the caving width of the working face.

[0051] The steel wire rope is lowered from the drilling hole to the working face, and the position of the steel wire rope exposed to the ground is fixed by using a tray and a lock.

[0052] A steel plate (support plate) is processed, the width of the steel plate is consistent with the caving width, the length of the steel plate is fixed, and a through hole is drilled at a specified position, so that the steel wire rope can pass through the through hole, the position of the steel wire rope exposed to the steel plate is fixed by using a tray and a lock, and the steel plate is tightly attached to the roof of the coal and rock body of the working face.

[0053] With the working face advancing forward, the above-mentioned three steps are repeated until the caving height is less than 2m.

[0054] On the basis of injecting high polymer material into the roof and coal wall of the working face, and because the caving height has been controlled to be below 2m, the anchor rod and anchor cable combined support method is adopted, that is, personnel stand at a safe position, drill anchor rods and anchor cables to the roof of the caving position, and lay lead wire mesh to protect the roof; glass steel anchor cables are drilled at the side and plastic mesh is laid to protect the side.

[0055] Further, when the support 13 is moved, the support is pulled under pressure and cannot be lowered.

[0056] The above two steps are repeated until the caving roof (coal seam top surface 8) is completely controlled.

[0057] As shown in Figures 1 to 7 The working face roof treatment method in the present application is a roof treatment method for fully mechanized working face of ultra-large mining height and shallow depth coal mine, which comprises the following steps:

[0058] S1. Analyze the roof falling reason.

[0059] S2. Drill a drilling hole (first protection hole 7) at a 15° inclination angle upward from a position 500mm below the roof (coal seam top surface 8) to the roof, the hole diameter of the drilling hole is 60mm, the spacing between two adjacent drilling holes is 2m, and the hole depth is 8m.

[0060] S3. Inject Malisan (protection material) into the drilling hole drilled to the roof until it flows out of the coal wall gap. The working face advances 3m, and the above step is repeated once until the caving roof is completely controlled.

[0061] S4. Drill a drilling hole (second protection hole 3) along the horizontal direction to the coal wall of the working face, the spacing is 2m, and the hole depth is 7m.

[0062] S5. Injecting the Mari into the drilled hole (second protection hole 3) of the working face, until the coal wall gap flows out. The working face advances 3m, and repeats once, until the falling roof is completely controlled.

[0063] S6. Measuring the working face position from the ground 9, and drilling a hole (first reinforcement hole) to the working face, every 9m symmetrically drilling two holes (first reinforcement hole), the distance between the two first reinforcement holes is the width of the falling roof.

[0064] S7. Lowering the φ22mm steel wire rope (first reinforcement rope 4) from the first reinforcement hole to the working face, and using the 300*300*16mm first tray 61 and the φ22mm first lock 51 to fix the position of the steel wire rope exposed to the ground.

[0065] S8. Processing a 5mm thick steel plate (support plate 2), the width of the steel plate is consistent with the falling width, the length is 10m, and a φ25mm through hole is drilled at the specified position, so that the steel wire rope can pass through the through hole, and the steel wire rope exposed to the steel plate is fixed using the 300*300*16mm second tray 62 and the φ22mm second lock 52, and the steel plate is tightly attached to the roof of the coal and rock mass of the working face.

[0066] S9. As the working face advances forward, repeat steps 6-8 above until the falling height is less than 2m.

[0067] S10. On the basis of injecting Mari into the roof of the working face, since the falling height has been controlled below 2m, the anchor rod and anchor cable combined support method is adopted, that is, personnel stand in a safe position, drill anchor rods and anchor cables to the roof of the falling area, and lay steel mesh to protect the roof; glass steel anchor cables are drilled in the side of the working face, and plastic mesh is laid to protect the side. The specific method is divided into lock support and falling area support:

[0068] The anchor rod and anchor cable support operation of the lock support is divided into two groups: one group from the side of the auxiliary transportation trough 11 to the inside of the working face, reinforcing and supporting the falling area, the support equipment is a single-arm anchor rod drill, the lock support adopts the "anchor cable + steel belt" method, the anchor cable specification is φ28.6mm*8000mm, the steel belt specification is 2m two-hole π type steel belt, the interval distance is 1m per row, and there are 2 sets of anchor cables per row. The second group from the side of the rubber transportation trough 12 to the inside of the working face, reinforcing and supporting the falling area, the support equipment is a single-arm anchor rod drill, the lock support adopts the "anchor cable + steel belt" method, the anchor cable specification is φ28.6mm*8000mm, the steel belt specification is 2m two-hole π type steel belt (connecting steel belt 22), the interval distance is 1m per row, and there are 2 sets of anchor cables per row. The principle of the two lock supports is to support row by row from the outside to the inside, and the anchor cable of each row must be tensioned before the next row of anchor cable construction can be carried out.

[0069] The roof of the roof fall area is supported by "anchor rod + steel mesh + steel belt + anchor cable" combined support, the mesh selects Φ6.5mm welded steel mesh (the first protective net 17), the mesh size is 150*150mm, and the mesh size is cut according to the size of the roof fall area. The anchor rod is the first anchor rod 16 of Φ22*2200mm left-handed thread steel without longitudinal reinforcement, 6 sets / m; the anchor cable is Φ22*8000mm steel strand (anchor cable 15), one meter one row, 1 row 3 sets, and the pressure is 5200*140*8mm three-eye π-shaped steel belt. The anchor rod and the anchor cable are supported row by row in turn, one row of anchor cable must be completed every two rows of anchor rods, and sporadic anchor rods and anchor cables are used for reinforcement when necessary, so that the roof support is reliable.

[0070] The coal wall of the roof fall area working face is supported by "anchor rod + mesh" combined support, the mesh selects 25kN high-strength double plastic mesh (the second protective net 19), the mesh size is 40*40mm, and the mesh size is cut according to the size of the roof fall area. The anchor rod is a φ32*2100mm glass steel anchor rod, the anchor rod row spacing is 1m, each row has 5 sets, and the uppermost row of anchor rods is 300mm away from the roof, and the remaining anchor rods are spaced 750m apart.

[0071] S11. When the moving support 13 is pulled, in order to prevent the controlled roof from falling due to a large descending support amplitude, the support must be pulled under pressure, and the support must not be lowered.

[0072] S12. Repeat steps 10-11 above until the falling roof is completely controlled.

[0073] Please refer to Figure 7 for a flowchart of the above 12 steps.

[0074] From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects:

[0075] (1) The present application adopts drilling from the ground, threading a steel wire rope, and suspending a steel plate at the working face position of the lower end of the steel wire rope, and fastening the steel plate to tightly adhere to the falling roof, thereby preventing the broken roof from continuing to fall, and providing a relatively safe working environment for the working face operators, overcoming the disadvantages of high falling height and the inability to use traditional roof fall anchor rod and anchor cable combined support methods;

[0076] (2) The present application adopts comprehensive measures such as segmental injection of high molecular materials, steel plate fixing of falling roof, anchor rod and anchor cable combined support, and pulling support under pressure, and the effect of treating the roof fall accident of the fully mechanized working face with large mining height and shallow depth is obvious;

[0077] (3) The method adopted by the present application is convenient for construction, and part of the process can be parallel operation, improving the operation efficiency and greatly shortening the roof fall treatment time.

[0078] The above merely provides the preferred embodiments of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the principles and technical scope of the present application shall fall into the scope of the present application.

Claims

1. A method of roof treatment of a working face, characterised by, The method comprises the following steps: drilling a first reinforcing hole to the top surface (8) of the coal seam working area (10) from the ground (9); lowering a first reinforcing rope (4) into the first reinforcing hole from the ground (9); fastening the two ends of the first reinforcing rope (4) that extend out of the ground and the top surface (8) of the coal seam, respectively; the method for fastening the end of the first reinforcing rope (4) that extends out of the ground comprises the following steps: installing a first lock (51) and a first tray (61) on the end of the first reinforcing rope (4) that extends out of the ground, the first reinforcing rope (4) is arranged on the first tray (61), and the first lock (51) is located on the side of the first tray (61) away from the ground and is locked with the first reinforcing rope (4); the method for drilling the first reinforcing hole comprises the following steps: drilling a row of first reinforcing holes along the width direction of the coal seam working area (10), and the row of first reinforcing holes comprises a plurality of pairs of first reinforcing holes; 2. The working face roof fall treatment method according to claim 1, characterized in that, when the height of the caving area above the top surface (8) of the coal seam is less than 2m, the working face roof falling treatment method further comprises the following steps: drilling a second reinforcing hole and a third reinforcing hole from the top surface (8) of the coal seam to the caving area; laying a first protective net (17) on the top surface (8) of the coal seam; 3. The working face roof fall treatment method according to claim 1, characterized in that, inserting a first anchor rod (16) into the second reinforcing hole through the first protective net (17), and inserting an anchor cable (15) into the third reinforcing hole; before drilling the first reinforcing hole, the working face roof falling treatment method further comprises the following steps:

4. The working face roof fall treatment method according to claim 1, characterized in that, drilling a first protective hole (7) from the coal seam working face (1) to the caving area above it; injecting protective material into the first protective hole (7) until the protective material flows out from the gap connected with the first protective hole (7). the method for fastening the end of the first reinforcing rope (4) that extends out of the top surface (8) of the coal seam comprises the following steps: making the first reinforcing rope (4) in each pair of first reinforcing holes pass through a support plate (2), and the support plate (2) is located on the side of the top surface (8) of the coal seam away from the ground (9); installing a second lock (52) and a second tray (62) on the end of the first reinforcing rope (4) that extends out of the support plate (2), the first reinforcing rope (4) is arranged on the second tray (62), and the second lock (52) is located on the side of the second tray (62) away from the support plate (2) and is locked with the first reinforcing rope (4). The working face roof falling processing method further comprises the following steps: with the forward advance of the coal seam working face (1), repeating the steps of drilling a first reinforcing hole and fastening the first reinforcing rope (4) along the advance direction of the coal seam working face (1) until the height of the caving area above the top surface (8) of the coal seam is less than 2m. The third reinforcing hole is a plurality of third reinforcing holes arranged in a row, and the method for inserting an anchor cable (15) into the third reinforcing hole comprises the following steps: making the anchor cables (15) in the plurality of third reinforcing holes in each row of third reinforcing holes pass through the same connecting steel belt (22).

5. The working face roof fall treatment method according to claim 3, characterized in that, When the height of the caving area above the top surface (8) of the coal seam is less than 2m, the roof fall treatment method of the coal seam working face further comprises: laying a second protective net (19) on the coal seam working face (1) and drilling second anchor rods (18) through the second protective net (19) to the coal seam working face (1).

6. The working face caving treatment method according to claim 1, characterized in that, The roof fall treatment method of the coal seam working face further comprises: With the forward advance of the coal seam working face (1), the steps of drilling the first protective hole (7) to injecting the protective material into the first protective hole (7) are repeated along the advance direction of the coal seam working face (1).

7. The working face caving treatment method according to any one of claims 1 to 5, characterized in that, Before drilling the first reinforcing hole, the roof fall treatment method of the coal seam working face further comprises: drilling a second protective hole (3) along the advance direction of the coal seam working face (1) and from the coal seam working face (1); injecting the protective material into the second protective hole (3) until the protective material flows out from the gap communicating with the second protective hole (3).

8. The working face roof fall treatment method according to claim 7, characterized in that, The roof fall treatment method of the coal seam working face further comprises: With the forward advance of the coal seam working face (1), the steps of drilling the second protective hole (3) to injecting the protective material into the second protective hole (3) are repeated along the advance direction of the coal seam working face (1).

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