Gob-side entry retaining roadside filling enhanced filling flexible structure and construction method thereof

Abstract

The invention provides a gob-side entry retaining roadside filling and enhanced filling flexible structure and a construction method of the gob-side entry retaining roadside filling and enhanced filling flexible structure, and belongs to the technical field of coal mine non-pillar mining gob-side entry retaining roadside supporting. Comprising standing formwork supporting single hydraulic props, reinforcing meshes, filling bags and filling flexible structures, the multiple single hydraulic props are divided into two rows, the reinforcing meshes are arranged on the inner sides of the two rows of single hydraulic props, the filling bags are located in the reinforcing meshes, and the filling flexible structures are located in the filling bags. The gob-side entry retaining structure has the beneficial effects that the supporting bearing capacity of the structure is high, the deformation resistance is good, the extra cost increment is low, and stable control over deep mining severe mine pressure gob-side entry retaining is facilitated; the construction method is simple and convenient in operation steps and low in economic cost, and the filling wall body can effectively construct roof contact and stably bear pressure.

Description

Technical Field

[0001] The present invention relates to the technical field of gob-side tunnel support for coal mines without coal pillars, and in particular to a gob-side tunnel reinforcement and filling flexible structure and a construction method thereof. Background Art

[0002] The technology of retaining tunnels along the goaf has been developed in China for many years. By reusing a tunnel for the second time, it has greatly improved the recovery rate of coal resources and alleviated the industry's dilemma of tight succession in coal mining. As coal mining gradually moves deeper, the mine pressure becomes more severe during the advancement of the working face. The filling bodies along the goaf-retained tunnels bear the deadweight load of the broken direct roof and the old roof during operation, and also the pressure from the old roof. The phenomenon of large deformation and bearing failure of the filling bodies along the goaf-retained tunnels is increasing. The technical implementation methods of goaf-retained tunnels have undergone continuous development, from traditional tunnel side support methods such as wooden pile support, dense pillar support and gangue belt support to the use of high-water quick-setting materials and paste materials for integral casting of tunnel side filling. The latter has become the main support form for tunnel side support along the goaf-retained tunnels at this stage due to its advantages of fast resistance increase speed, good sealing and high degree of mechanization. However, the side fillings constructed with these materials usually have low bearing strength and weak deformation resistance. In order to adapt to the impact of severe mining pressure in deep mining, the side fillings are becoming wider and wider, resulting in increased material demand, high long-distance auxiliary transportation costs, and insufficient control of surrounding rock deformation. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies in the background technology and provide a flexible structure for reinforced filling along the gob-side entry and a construction method thereof.

[0004] In order to achieve the above-mentioned purpose of the invention, the technical solution adopted by the present invention is specifically: a flexible structure for reinforcing filling along the side of the goaf and retaining the tunnel, including a single hydraulic pillar for vertical formwork support, a steel mesh, a filling bag and a flexible filling structure. A plurality of the single hydraulic pillars are divided into two rows, which are vertically supported at equal distances on the ground along the side of the goaf and along the side of the tunnel in the area to be filled. The steel mesh is arranged on the inner side of the two rows of single hydraulic pillars, the filling bag is located inside the steel mesh, the bag body of the filling bag is connected to the external steel mesh, and the flexible filling structure is located inside the filling bag and is arranged at equal distances along the central axis of the projection of the wall to be filled to the ground.

[0005] Furthermore, multiple pieces of the steel mesh are leaning against and hung inside two rows of single hydraulic pillars, and are arranged in sequence on both sides of the width direction of the area to be filled, and a supporting wall is set up above and around the area to be filled to form a space for constructing the supporting wall. The steel mesh on the narrow side of the working surface of the area to be filled is hung with a delayed bolted cross bar.

[0006] Furthermore, the bolted cross bar includes a rod body, one end of the rod body is fixedly connected to the bent rod handle, and the other end is equidistantly provided with a plurality of bolt holes, a detachable bolt head is inserted into the bolt hole, and an iron chain is connected between the bolt head and the rod body, and the plurality of bolted cross bars are equidistantly provided on the narrow side facing the working surface of the area to be filled.

[0007] Furthermore, the filling bag is a three-dimensional structure with an open top. The filling bag is arranged in the space to be constructed of the supporting wall, its open end is connected to the top plate of the area to be filled, and its bottom plate is abutted against the bottom plate of the area to be filled. The bag body of the filling bag is connected to the steel mesh around the outside, and the filling flexible structure is located inside the filling bag and is arranged at equal intervals along the central axis of the projection of the wall to be filled to the ground.

[0008] Furthermore, the filling flexible structure includes a large-diameter cylindrical outer frame steel skeleton, multi-layer flexible steel wire mesh columns, supporting longitudinal steel bars for the mesh columns, transverse connecting steel bars between the mesh columns and tension anchor rods, and the tension anchor rods penetrate the steel skeleton and the multi-layer flexible steel wire mesh columns.

[0009] The steel skeleton has a diameter of two-thirds of the width of the wall to be filled, and its height is equivalent to the height of the wall to be filled, and is arranged at equal distances along the central axis of the wall to be filled projected onto the ground. The steel skeleton includes a plurality of vertically collinear parallel steel rings and at least eight vertical steel bars welded together, and a plurality of the vertical steel bars are distributed at equal angles on the circumferential side walls;

[0010] The multi-layer flexible steel wire mesh column is made of a tough steel wire mesh rolled into a mesh column shape on the ground and spot-welded into a whole, and the overlapping mesh holes are bound by steel wires. The diameter of the outermost layer of the multi-layer flexible steel wire mesh column is adapted to the diameter of the steel skeleton, and the diameter of the inner layer of the mesh column gradually decreases;

[0011] The supporting longitudinal reinforcement of the mesh column is formed by binding a number of steel bars with the same length as the height of the wall to be filled and the flexible steel wire mesh column through the inner mesh holes by steel wire;

[0012] The horizontal connecting steel bars between the posts are arranged in two rows, with two steel bars in each row, and they respectively pass through all the posts in the area to be filled horizontally to form a whole;

[0013] Both ends of the tension anchor rod are provided with external thread sections, and the two ends of the tension anchor rod are respectively passed through the reserved holes provided on the filling bag, and the rod body of the tension anchor rod is inserted through the filling flexible structure, the filling bag and the steel mesh, and the two ends are respectively passed through the steel mesh, the matching ladder beam on the outside of the steel mesh and the tension anchor rod tray on the outside of the ladder beam from the inside to the outside, and the two ends of the tension anchor rod are respectively fastened by nuts; a rod-penetrating canvas tube is connected to the reserved hole, and the rod-penetrating canvas tube and the rod body of the tension anchor rod are fastened by industrial cable ties or iron wire.

[0014] The present invention also provides a gob-side entry retaining tunnel filling construction method, comprising the following steps:

[0015] S1: Plan the area to be filled, clean the floating coal, gangue and debris on the bottom plate, make the bottom plate relatively flat, and leave enough space for the formwork pillars to be erected;

[0016] S2: Arrange single hydraulic pillars for formwork support at equal intervals on the side of the roadway and the side of the goaf in the area to be filled, then set steel mesh inside the two rows of single hydraulic pillars, and hang the steel mesh inside the single hydraulic pillars of the formwork support. Leave gaps on the narrow side facing the goaf, which are the two ends of the area to be filled, to form the space to be filled;

[0017] S3: Place the filling bag through the gap left in the narrow surface of the temporary mining into the space to be filled, and adjust the position; then insert the large-diameter cylindrical outer frame steel bar skeleton into the reserved gap and lay it down horizontally, and insert the multi-layer flexible steel mesh columns prefabricated on the ground from the top of the horizontally placed large-diameter cylindrical outer frame steel bar skeleton in order from large to small in diameter; then stand the entire large-diameter cylindrical outer frame steel bar skeleton upright and place it on the central axis of the ground in the area to be filled, and adjust the position of the internal mesh columns to be centered; repeat the above steps of placing the multi-layer flexible steel mesh columns, arrange the remaining flexible mesh columns at equal intervals, and finally insert the horizontal connecting steel bars between the mesh columns at the bottom quarter and the top quarter respectively to form all the multi-layer flexible steel mesh columns into a whole;

[0018] S4: Place the bottom of the filling bag in contact with the bottom plate of the area to be filled, then pull the filling bag mouth upward to contact the top plate, temporarily fix it to the upper part of the steel mesh on both sides, and insert the tension anchor rods in sequence from bottom to top through the reserved holes; use bolted cross bars to insert and fix them in opposite directions at the top, upper quarter point, middle part, and lower quarter point of the steel mesh, then arrange the steel mesh to seal the temporary mining gap, hang the steel mesh on the bolted cross bars, and ensure that the side wall of the filling bag fits the surrounding steel mesh;

[0019] S5: Tighten the reserved hole through-rod canvas tube and the tension anchor rod with nylon tie or thin wire to prevent the high-water-fast-setting filling material slurry from leaking out. Extend the filling pumping pipe through the upper opening of the filling bag into the innermost grid column of the filling flexible structure to pour the high-water-fast-setting filling material until the filling bag is completely filled;

[0020] S6: After the high-water quick-setting filling material reaches the required support strength, remove the two rows of formwork supporting single hydraulic pillars and the steel mesh and bolted cross bars on the narrow side facing the working surface to form a section of filling wall;

[0021] S7: As the mining face continues to advance, steps S1 to S6 are repeated to continue constructing the next section of the filling wall, and ensure that the next section of the filling wall is adjacent to the previous section of the filling wall, fully ensuring the continuity between the divided walls.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. Compared with the general filling material integral pouring tunnel filling technology, the present invention still retains the advantages of fast resistance increase speed, high filling mechanization degree, convenient construction, etc., and at the same time has the characteristics of strengthening and toughening, and overall stability of the filling body. It has ideal support effect, strong bearing capacity, and good anti-deformation ability, which is conducive to the stable control of the tunnel left along the gob under severe mining pressure in deep mining.

[0024] 2. The enhanced filling flexible structure proposed in the present invention is based on the idea of ​​layered deformation restraint of the internal flexible steel wire mesh and overall strengthening support of the filling skeleton. It successfully achieves the improvement of the bearing performance of the filling body beside the gob-side tunnel based on the existing filling materials.

[0025] 3. The present invention can achieve effective gains in the bearing performance of the filling body along the goaf-retained tunnel based on a relatively low additional economic cost increment. The flexible filling structure is easy to process and has low economic cost. The construction method and operation steps are simple. The filling wall can be effectively constructed and connected to the top, and the pressure can be stably borne. The bearing efficiency and deformation resistance of the filling body are greatly improved, which is beneficial to ensuring safe production in coal mines.

[0026] 4. The present invention proposes a flexible structure for reinforcing filling along the side of a goaf-retained tunnel. The structure has ideal supporting effect, strong bearing capacity, good deformation resistance, and low additional cost increment, which is beneficial to the stable control of goaf-retained tunnels under severe mining pressure in deep mining. The present invention also proposes a construction method for filling along the side of a goaf-retained tunnel. The construction method has simple operation steps and low economic cost, and can realize the effective construction of the filling wall to connect to the top and stably bear pressure, which greatly improves the bearing efficiency and deformation resistance of the filling body, and is beneficial to ensuring safe production in coal mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0028] Figure 1 It is an overall schematic diagram of the filling structure in the present invention.

[0029] Figure 2 It is a structural schematic diagram of the cross bar with bolts in the present invention.

[0030] Figure 3 This is a schematic diagram of a single filling flexible structure in the present invention.

[0031] Figure 4 This is a schematic diagram of the connection between two filling flexible structures in the present invention.

[0032] Wherein, the accompanying drawings are marked as follows:

[0033] 1. Single hydraulic prop; 2. Steel mesh; 3. Filling bag;

[0034] 4. Filling flexible structure; 4-1. Steel skeleton; 4-2. Multi-layer flexible steel wire mesh columns; 4-3. Supporting longitudinal steel bars for mesh columns; 4-4. Transverse connecting steel bars between mesh columns;

[0035] 5. Crossbar with bolt; 5-1. Bent handle; 5-2. Bolt hole; 5-3. Bolt head; 5-4. Chain; 5-5. Rod body;

[0036] 6. Tie anchor tray on the outside of the ladder beam;

[0037] 7. Ladder beams are provided on the outside of the steel mesh;

[0038] 8. Tension anchor rods. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. Of course, the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0040] Example

[0041] like Figures 1-4 As shown, the present invention provides a flexible structure for enhanced filling along the side of a gob-side tunnel retaining tunnel, comprising a single hydraulic support pillar 1 for supporting a formwork, a steel mesh 2, a filling bag 3 and a flexible filling structure 4.

[0042] Multiple single hydraulic props 1 are divided into two rows and vertically supported at equal distances along the side of the reserved roadway and along the side of the goaf in the area to be filled;

[0043] Multiple steel meshes 2 are hung inside two rows of single hydraulic pillars 1 and are sequentially arranged on both sides of the width direction of the area to be filled. A support wall is set up around and above the area to be filled to form a space to be constructed. The steel meshes 2 on the narrow side of the area to be filled facing the working surface are hung laterally by bolted cross bars 5.

[0044] The steel mesh 2 should be overlapped and tied to form a whole mesh surface. The overlapping mesh area is fixed with steel wire. The narrow steel mesh 2 facing the working surface in the area to be filled is hung laterally by the bolted crossbar 5.

[0045] The bolted cross bar 5 includes a rod body 5-5, one end of the rod body 5-5 has a bent rod handle 5-1, and the other end of the rod body 5-5 is drilled with bolt holes 5-2 at regular intervals, and bolt heads 5-3 can be inserted and fixed. The bolt heads 5-3 are fixedly connected to the rod body 5-5 by an iron chain 5-4. The distance between the bolt hole 5-2 and the end of the bent rod handle 5-1 meets the general design specifications of the width of the tunnel side filling body. The bolted cross bar 5 is inserted in four directions near the top, upper quarter point, middle part, and lower quarter point of the steel mesh 2.

[0046] The filling bag 3 is a three-dimensional structure with an upper opening, the open end of which can be connected to the top plate of the area to be filled, and the lower end can be flush with the bottom plate; the filling bag 3 is arranged in the space to be constructed of the supporting wall, the bottom plate of which is in contact with the bottom plate of the area to be filled, the bag body is connected to the steel mesh 2 around the outside, and the top is in contact with the top plate of the area to be filled. The filling flexible structure 4 is arranged at equal intervals inside along the axis of the wall to be filled, and the high-water quick-setting material can be uniformly poured inside to be consistent with the outside, or gangue aggregate can be added to mix with the high-water quick-setting material;

[0047] The filling flexible structure 4 is composed of a large diameter cylindrical outer frame steel skeleton 4-1, multi-layer flexible steel wire mesh columns 4-2, supporting longitudinal steel bars 4-3 for the mesh columns, transverse connecting steel bars 4-4 between the mesh columns, and tension anchor rods 8 that penetrate the steel skeleton 4-1 and the multi-layer flexible steel wire mesh columns 4-2;

[0048] The diameter of the large-diameter cylindrical outer frame steel skeleton 4-1 is two-thirds of the width of the wall to be filled, and its height is equivalent to the wall height. It is arranged at equal distances along the central axis of the wall. The main body is welded and fixed by a number of vertically collinear parallel steel rings and root vertical steel bars. The root steel bars are distributed at equal angles around the circumference. The bottom ring is fixed to the clustered steel bars radiating from the center of the circle. The radial surface steel bars are connected to a square steel frame with a side length of . times the diameter of the cylinder.

[0049] The multi-layer flexible steel wire mesh column 4-2 is made of high-toughness steel wire mesh rolled into a mesh column shape on the ground and spot-welded into a whole. The overlapping mesh holes are bound by steel wire. The diameter of the outermost layer of mesh column is adapted to the diameter of the large-diameter cylindrical outer frame steel skeleton 4-1. The diameter of the inner mesh column gradually decreases. The manufacturing method of the mesh column is the same as that of the outermost layer of mesh column. The number of inner layers is optimized according to the work needs.

[0050] The supporting longitudinal reinforcement 4-3 of the mesh column is formed by binding a number of steel bars of the same length as the wall with the inner mesh holes of the flexible steel wire mesh column by steel wire. It is required to be arranged equally on the circumference. Whether the inner layer of small-diameter mesh columns need supporting longitudinal reinforcement can be determined according to actual needs.

[0051] The horizontal connecting steel bars 4-4 between the posts are two rows of sufficiently long toughness steel bars. Each row of steel bars can penetrate all the posts in the area to be filled horizontally at the upper and lower parts to form a whole.

[0052] External thread sections are provided at both ends of the tension anchor rod 8. The number of tension anchor rods 8 is set according to the design requirements of the reinforced support of the filling wall. The two ends of the tension anchor rod 8 are respectively passed through a pair of reserved holes opened on the filling bag 3. The rod body is inserted into the multi-layer filling flexible structure 4 and the large-diameter cylindrical outer frame steel skeleton 4-1. The two ends pass through the steel mesh 2, the matching ladder beam on the outside of the steel mesh and the tension anchor rod tray 6 on the outside of the ladder beam from the inside to the outside, and then are connected with the anchor rod external thread through a nut to apply pre-tightening force; a rod-penetrating canvas tube is connected to the reserved hole, and the rod-penetrating canvas tube and the anchor rod body can be tightened by industrial cable ties or wire.

[0053] In order to better achieve the above-mentioned invention effects, the present invention also provides a method for constructing gob-side entry retaining and backfilling, which comprises the following steps:

[0054] The first step is to plan the area to be filled, clean the floating coal, gangue and debris on the bottom plate, make the bottom plate relatively flat, and leave enough space for the formwork pillars to be erected;

[0055] In the second step, first, formwork support single hydraulic pillars 1 are arranged at equal intervals on the side of the roadway and the side of the goaf in the area to be filled, and then steel meshes 2 are set on both sides of the hydraulic pillars, and the steel meshes 2 are hung on the inner side of the formwork support single hydraulic pillars 1, leaving a gap on the narrow side near the goaf to form a space to be filled;

[0056] The third step is to first place the filling bag 3 from the narrow surface with a gap to the space to be filled, and adjust the position; then lay the large-diameter cylindrical outer frame steel frame 4-1 down horizontally, and then insert the flexible steel wire mesh columns prefabricated on the ground into the interior of the large-diameter cylindrical outer frame steel frame 4-1 in order from large to small in diameter from the top; stand the entire large-diameter cylindrical outer frame steel frame 4-1 upright, place it on the axis of the area to be filled, and adjust the position of the internal mesh columns to be centered; repeat the above steps of placing multiple layers of flexible steel wire mesh columns 4-2, arrange the remaining flexible mesh columns at equal intervals, and finally insert the horizontal connecting steel bars 4-4 between the mesh columns at the bottom quarter and the top quarter respectively to form all the multiple layers of flexible steel wire mesh columns 4-2 into a whole, with two on the top and two on the bottom, and the spacing is one-third of the outer frame cylinder diameter;

[0057] The fourth step is to abut the bottom of the filling bag 3 with the bottom plate of the area to be filled, then pull the filling bag 3 upward to abut the top plate, and temporarily fix it to the upper part of the steel mesh 2 on both sides. According to the design requirements of the support wall reinforcement support, the tension anchor rods 8 are inserted from bottom to top through the reserved holes. The temporary fixation of the filling bag 3 can be released to adjust the position of the tension anchor rods 8 for insertion correction, so that each tension anchor rod 8 can correspond to the reserved holes on both sides one by one; use the bolted cross bar 5 to insert and fix it at the top, upper quarter point, middle and lower quarter point of the adjacent steel mesh 2, and then arrange the steel mesh 2 at the temporary mining gap to seal the gap, and hang the steel mesh 2 on the bolted cross bar 5; ensure that the side wall of the filling bag 3 is in contact with the surrounding steel mesh 2;

[0058] Step 5: Tighten the reserved hole through-rod canvas tube and the tension anchor rod 8 with nylon tie or thin wire to prevent the high-water-fast setting filling material slurry from leaking out. Extend the filling pumping pipe into the innermost net column of the filling flexible structure 4 through the upper opening of the filling bag 3 to pour the high-water-fast setting filling material until the filling bag 3 is completely filled. A stirring vibration rod can be added to assist in filling to promote flow and expel bubbles.

[0059] Step 6: After the high-water quick-setting filling material reaches the required support strength, remove the two rows of formwork supporting single hydraulic pillars 1 and the steel mesh 2 and bolted cross bars 5 on the narrow side facing the working surface to form a section of filling wall;

[0060] Step 7. As the mining face continues to advance, repeat steps 1 to 6 to continue constructing the next section of the filling wall, and ensure that the next section of the filling wall is adjacent to the previous section of the filling wall to fully ensure the continuity between the various divided walls.

[0061] In summary, the present invention provides a flexible structure 4 for reinforcing filling along the side of a gob-side tunnel and a construction method thereof, specifically including a flexible structure for reinforcing filling along the side of a tunnel and a filling construction method.

[0062] Filling enhanced filling flexible structure: The filling formwork frame beside the lane is overlapped and supported by a single hydraulic pillar 1, which is set in the area to be filled near the laneway side and the goaf side; multiple steel meshes 2 are leaning against the single hydraulic pillar 1, and are set around the area to be filled. The steel meshes 2 are overlapped and tied together by steel wires; filling bags 3 are installed to ensure that the filling bags 3 are respectively against the top and bottom plates of the remaining lane, and an enhanced filling flexible structure 4 is set inside. The filling bag 3 includes an enhanced filling flexible structure 4 inside, which can be uniformly filled with high-water quick-setting filling materials; the enhanced filling flexible structure 4 is composed of a large-diameter cylindrical outer frame It consists of a steel frame 4-1, multi-layer flexible steel wire mesh columns 4-2, supporting longitudinal steel bars 4-3 for the mesh columns, transverse connecting steel bars 4-4 between the mesh columns and tension anchor rods 8 that pass through the steel frame 4-1 and the multi-layer flexible steel wire mesh columns 4-2. The interior of the reinforced filling flexible structure can be uniformly filled with high-water quick-setting material or mixed gangue high-water filling material; the mesh diameter of the multi-layer flexible steel wire mesh columns 4-2 is adapted to the tension anchor rods 8, which makes it convenient for the tension anchor rods 8 to pass through the reinforced filling flexible structure 4 and be connected to its outer ladder beam, anchor tray and nut through the steel mesh 2.

[0063] Construction method: Deploy the formwork frame, overlap the supporting single hydraulic props 1 and the steel mesh 2; place the filling bags 3 and the filling flexible structure 4; insert the tension anchors 8; fill the roadway filling material; and form the roadway filling wall. After the wall stabilizes, the tension anchors 8 are applied to strengthen the wall with pre-tightening force. This structure and method creates an ideal support structure for the gob-side roadway retaining, significantly improving the bearing strength and deformation resistance of the filling support wall.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A flexible structure for enhanced filling along the side of a gob-side entry retaining tunnel, characterized in that: The invention comprises a formwork supporting single hydraulic pillar (1), a steel mesh (2), a filling bag (3) and a filling flexible structure (4); a plurality of the single hydraulic pillars (1) are divided into two rows and vertically supported at equal distances on the ground along the side of the reserved lane and along the side of the goaf in the area to be filled; the steel mesh (2) is arranged inside the two rows of single hydraulic pillars (1); the filling bag (3) is located inside the steel mesh (2); the bag body of the filling bag (3) is connected to the external steel mesh (2); the filling flexible structure (4) is located inside the filling bag (3) and is arranged at equal distances along the central axis of the wall to be filled projected onto the ground.

2. A flexible structure for enhanced filling along the gob-side entry retaining according to claim 1, characterized in that: A plurality of steel meshes (2) are hung inside two rows of single hydraulic supports (1) and are sequentially arranged on both sides of the width direction of the area to be filled, and a supporting wall is set up around and above the area to be filled to form a space to be constructed. The steel mesh (2) on the narrow side of the area to be filled facing the working surface is hung laterally by a bolted cross bar (5).

3. A flexible structure for enhanced filling along the gob-side entry retaining according to claim 2, characterized in that: The bolted cross bar (5) comprises a rod body (5-5), one end of the rod body (5-5) is fixedly connected to a bent rod handle (5-1), and the other end is provided with a plurality of bolt holes (5-2) at equal intervals, a detachable bolt head (5-3) is inserted into the bolt hole (5-2), and an iron chain (5-4) is provided between the bolt head (5-3) and the rod body (5-5), and a plurality of bolted cross bars (5) are equidistantly provided on the narrow surface of the working surface of the area to be filled.

4. The flexible structure for enhanced filling along the gob-side entry retaining according to claim 1 is characterized in that: The filling bag (3) is a three-dimensional structure with an upper opening. The filling bag (3) is arranged in the space to be constructed of the supporting wall, with its open end connected to the top plate of the area to be filled, and its bottom plate abutting against the bottom plate of the area to be filled. The bag body of the filling bag (3) is connected to the steel mesh (2) around the outside. The filling flexible structure (4) is located inside the filling bag (3) and is arranged at equal intervals along the central axis of the projected wall to the ground.

5. The flexible structure for enhanced filling along the gob-side entry retaining according to claim 1 is characterized in that: The filling flexible structure (4) comprises a large-diameter cylindrical outer frame steel skeleton (4-1), multi-layer flexible steel wire mesh columns (4-2), longitudinal steel bars (4-3) supporting the mesh columns, transverse connecting steel bars (4-4) between the mesh columns, and tension anchor rods (8), wherein the tension anchor rods (8) penetrate the steel skeleton (4-1) and the multi-layer flexible steel wire mesh columns (4-2). The steel frame (4-1) has a diameter of two-thirds of the width of the wall to be filled, and its height is equivalent to the height of the wall to be filled, and is arranged at equal distances along the central axis of the wall to be filled projected onto the ground. The steel frame (4-1) includes a plurality of vertically collinear parallel steel rings and at least eight vertical steel bars welded together, and a plurality of the vertical steel bars are distributed at equal angles on the circumferential side wall. The multi-layer flexible steel wire mesh column (4-2) is made of a tough steel wire mesh rolled into a mesh column shape on the ground and spot-welded into a whole, with overlapping meshes bound by steel wires. The diameter of the outermost mesh column of the multi-layer flexible steel wire mesh column (4-2) is adapted to the diameter of the steel frame (4-1), and the diameter of the inner mesh column decreases gradually. The longitudinal reinforcement (4-3) of the mesh column is formed by binding a number of reinforcement bars of the same length as the height of the wall to be filled with flexible steel wire mesh columns through the inner mesh holes by steel wire; The horizontal connecting steel bars (4-4) between the posts are arranged in two rows, with two steel bars in each row, and they respectively pass through all the posts in the area to be filled horizontally to form a whole; Both ends of the tension anchor rod (8) are provided with external thread sections, and the two ends of the tension anchor rod (8) are respectively passed through the reserved holes provided on the filling bag (3), and the rod body of the tension anchor rod (8) is inserted through the filling flexible structure (4), the filling bag (3) and the steel mesh (2), and the two ends are respectively passed from the inside to the outside through the steel mesh (2), the ladder beam outside the steel mesh (2) and the tension anchor rod tray (6) outside the ladder beam, and the two ends of the tension anchor rod (8) are respectively fastened by nuts; a rod-penetrating canvas tube is connected to the reserved hole, and the rod-penetrating canvas tube and the rod body of the tension anchor rod (8) are fastened by industrial cable ties or iron wire.

6. A method for constructing side filling for a gob-side entry retaining, the method being based on a gob-side entry retaining side filling reinforced flexible structure according to any one of claims 1 to 5, characterized in that: The steps include: S1: Plan the area to be filled, clean the floating coal, gangue and debris on the bottom plate, make the bottom plate relatively flat, and leave enough space for the formwork pillars to be erected; S2: Formwork support single hydraulic pillars (1) are arranged at equal intervals on the side of the roadway and the side of the goaf in the area to be filled, and then steel meshes (2) are arranged inside the two rows of single hydraulic pillars (1), and the steel meshes (2) are hung inside the formwork support single hydraulic pillars (1), leaving a gap on the narrow side near the goaf to form a space to be filled; S3: Place the filling bag (3) from the narrow surface with a gap to the space to be filled, and adjust the position; then lay the large-diameter cylindrical outer frame steel frame (4-1) down horizontally, and insert the multi-layer flexible steel wire mesh columns (4-2) prefabricated on the ground from the top of the horizontally placed large-diameter cylindrical outer frame steel frame (4-1) into its interior in descending order of diameter; then stand the entire large-diameter cylindrical outer frame steel frame (4-1) upright, and place it on the central axis of the ground in the area to be filled, and adjust the position of the internal mesh columns to be centered; repeat the above steps of placing the multi-layer flexible steel wire mesh columns (4-2), and arrange the remaining flexible mesh columns at equal intervals, and finally insert the transverse connecting steel bars (4-4) between the mesh columns at the bottom quarter and the top quarter respectively to form all the multi-layer flexible steel wire mesh columns (4-2) into a whole; S4: The bottom of the filling bag (3) is brought into contact with the bottom plate of the area to be filled, and then the opening of the filling bag (3) is pulled upward to contact the top plate, and temporarily fixed to the upper part of the steel mesh (2) on both sides, and the tension anchor rods (8) are inserted in sequence from bottom to top through the reserved holes; a bolted cross bar (5) is used to insert and fix it in four directions at the top, the upper quarter point, the middle part, and the lower quarter point of the steel mesh (2), and then the steel mesh (2) is arranged at the temporary mining gap to seal the gap, and the steel mesh (2) is hung on the bolted cross bar (5) to ensure that the side wall of the filling bag (3) is in contact with the surrounding steel mesh (2); S5: Tighten the reserved hole through-rod canvas tube and the tension anchor rod (8) with nylon tie or thin iron wire to prevent the high-water-fast-setting filling material slurry from leaking out, extend the filling pumping pipe into the innermost grid column of the filling flexible structure (4) through the upper opening of the filling bag (3), and pour the high-water-fast-setting filling material until the filling bag (3) is completely filled; S6: After the high-water quick-setting filling material reaches the required support strength, the two rows of formwork supporting single hydraulic pillars (1) and the steel mesh (2) and bolted cross bars (5) on the narrow side facing the working surface are removed to form a section of filling wall; S7: As the mining face continues to advance, repeat steps S1 to S6 to continue constructing the next section of the filling wall, and ensure that the next section of the filling wall is adjacent to the previous section of the filling wall, fully ensuring the continuity between the divided walls.

Images