A soft thick coal seam roadway sub-supporting structure

Abstract

The utility model relates to mine roadway supporting technical field, concretely relates to a soft thick coal seam roadway sub -supporting structure. Include: the advance support unit forms the advance fixed -jet reinforcement plate, the first support unit includes the metal net, and the metal net is arranged on the bottom surface of the advance fixed -jet reinforcement plate located in the roadway top, the reinforced support unit includes at least one support module, and the support module includes the shed roof, left shed leg and right shed leg, and left shed leg and right shed leg are located in the opposite sides of roadway, and the bottom end of left shed leg and right shed leg is connected with the roadway bottom, the top end of left shed leg extends and forms the first connecting part, and the top end of right shed leg extends and forms the second connecting part, and the opposite ends of shed roof are connected with the first connecting part, the second connecting part, and the top end of shed roof abuts on the metal net. In this way, the problem that the slurry is difficult to diffuse and penetrate, and the loose coal and rock mass is easy to leak from the gap between the pipe shed, and forms the local empty area problem in the existing advance grouting reinforcement and advance pipe shed support is solved.

Description

Technical Field

[0001] This utility model relates to the field of mine roadway support technology, and more specifically, to a multi-stage support structure for soft, thick coal seam roadways. Background Technology

[0002] As coal mining depth increases, the stability of the surrounding rock during coal seam roadway excavation becomes increasingly prominent. These coal seams are characterized by low strength, loose and fractured structure, and extremely poor self-stabilizing ability. During roadway excavation with the roof coal remaining, the loose roof is highly susceptible to collapse, potentially leading to large-scale roof collapses and seriously threatening underground operational safety.

[0003] Due to these geological conditions, temporary support in the unsupported roof area of ​​the tunneling face faces significant technical challenges. The traditional "tunneling-supporting" cyclical operation mode is difficult to implement, and it is impossible to guarantee the standard procedure of temporary support only after tunneling a single anchor bolt support row spacing. It is necessary to adopt the "tunneling and supporting simultaneously" operation method and use scaffolding for permanent support. This prevents the full utilization of the mechanization advantages of fully mechanized tunneling equipment, resulting in low tunneling efficiency, which has become a key technical bottleneck restricting the rapid tunneling of coal seam roadways.

[0004] Currently, the main methods for pre-reinforcement and support of loose roofs in coal seam roadways are pre-grouting reinforcement and pre-pipe roof support, which have significant limitations in engineering applications. Coal seams are dense yet soft, lacking an effective network of fractures or pores, making it difficult for grout to diffuse and penetrate. This limits the range of grouting reinforcement, preventing the formation of a continuous and stable consolidated body and failing to improve the overall integrity of the surrounding rock. While pre-pipe roof support can provide some temporary support, the high degree of fragmentation in the loose roof allows loose coal and rock to easily leak through the gaps in the pipe roof, creating localized voids. This leads to stress concentration and instability of the support structure, failing to fundamentally prevent roof collapse. Utility Model Content

[0005] To address the problems in existing advanced grouting reinforcement and advanced pipe roof support where grout is difficult to diffuse and penetrate, and loose coal and rock masses are prone to leaking from the gaps in the pipe roof, forming local voids, this utility model provides a multi-stage support structure for soft, thick coal seam roadways.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A multi-stage support structure for roadways in soft, thick coal seams, comprising:

[0008] The advanced support unit is formed by advanced directional shotcreting at the top plate position of the roadway cross-section outline to create an advanced fixed shotcrete reinforcement plate.

[0009] The primary support unit includes a metal mesh, which is arranged on the bottom surface of the pre-sprayed reinforcement plate located at the top of the roadway.

[0010] The reinforced support unit includes at least one support module. Each support module includes a roof, a left support leg, and a right support leg. The left and right support legs are located on opposite sides of the roadway, and their bottom ends are connected to the bottom of the roadway. The top of the left support leg extends towards the side where the right support leg is located to form a first connecting portion, and the top of the right support leg extends towards the side where the left support leg is located to form a second connecting portion. One end of the roof is connected to the first connecting portion, and the other end of the roof is connected to the second connecting portion. The top of the roof abuts against the metal mesh.

[0011] In some embodiments, the primary support unit further includes a first anchor cable, one end of which is fixed to a metal mesh, and the other end of which passes through the pre-spraying reinforcement plate and extends into the roadway rock strata.

[0012] In some embodiments, the anchoring end of the first anchor cable penetrates into the roadway rock strata to a depth of not less than 1m.

[0013] In some embodiments, a first stepped surface is formed at the top of the first connecting portion, and a second stepped surface is formed at the top of the second connecting portion, with the opposite ends of the canopy placed on the first stepped surface and the second stepped surface, respectively.

[0014] In some embodiments, the first connecting portion includes a first connecting segment and a first functional segment. The first connecting segment extends toward the top of the left canopy leg toward the first functional segment. The top of the first functional segment has a first stepped surface, and the height of the first stepped surface is lower than the height of the top of the first connecting segment.

[0015] The second connecting part includes a second connecting segment and a second functional segment. The second connecting segment extends toward the top of the right canopy leg toward the second functional segment. The top of the second functional segment forms a second stepped surface. The height of the second stepped surface is lower than the height of the top of the second connecting segment.

[0016] When the two opposite ends of the canopy are placed on the first step surface and the second step surface respectively, the height of the top of the canopy is level with the height of the top of the first connecting segment and the top of the second connecting segment respectively.

[0017] In some embodiments, the support module further includes a second anchor cable and a third anchor cable, one end of the second anchor cable being fixed to the left support leg and the other end of the second anchor cable passing through the left support leg and extending into the sidewall of the tunnel rock stratum, one end of the third anchor cable being fixed to the right support leg and the other end of the third anchor cable passing through the right support leg and extending into the sidewall of the tunnel rock stratum.

[0018] In some embodiments, the support module further includes a fourth anchor cable and a fifth anchor cable. One end of the fourth anchor cable is fixed to the first connecting part, and the other end of the fourth anchor cable passes through the roof and the pre-spraying reinforcement plate and extends into the roadway rock strata. One end of the fifth anchor cable is fixed to the second connecting part, and the other end of the fifth anchor cable passes through the roof and the pre-spraying reinforcement plate and extends into the roadway rock strata.

[0019] In some embodiments, the first anchor cable is a plurality of first anchor cables arranged in a grid pattern;

[0020] Along the width of the tunnel, the fourth and fifth anchor cables are located between two adjacent columns of the first anchor cables.

[0021] To address the problems in existing advanced grouting reinforcement and advanced pipe roof support systems, such as the difficulty in grout diffusion and penetration, and the tendency for loose coal and rock masses to leak from the gaps in the pipe roof, forming local voids, this utility model has the following advantages:

[0022] By performing advanced directional shotcreting at the top plate position of the roadway cross section outline, an advanced support unit is formed to control the loose roof of the coal seam roadway, enabling rapid tunneling under the advanced fixed shotcreting reinforcement plate;

[0023] The primary support unit is used in conjunction with the reinforced support unit to facilitate rapid installation, thereby reducing labor intensity and further improving support efficiency. Attached Figure Description

[0024] Figure 1 A schematic diagram of the multi-stage support structure for a roadway section in a soft, thick coal seam is shown.

[0025] Figure 2 It shows Figure 1 The diagram shows the structure of the CC section line.

[0026] Attached diagram labels: 10-Road strata; 11-Advanced fixed shotcrete reinforcement plate; 12-Metal mesh; 13-First anchor cable; 14-Roof; 15-Left canopy leg; 16-Right canopy leg; 17-Second anchor cable; 18-Third anchor cable; 19-Fourth anchor cable; 20-Fifth anchor cable. Detailed Implementation

[0027] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, and are not intended to imply any limitation on the scope of the disclosure.

[0028] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments and are not intended to limit the indicated devices, elements, or components to having a specific orientation or being constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientations or positional relationships; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances. In addition, the terms "installed", "set up", "equipped with", "connected", and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. Furthermore, the terms "first," "second," etc., are mainly used to distinguish different devices, elements, or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0029] This embodiment discloses a multi-stage support structure for soft, thick coal seam roadways, such as... Figure 1 and Figure 2 As shown, the multi-stage support structure for the soft, thick coal seam roadway includes:

[0030] The advanced support unit is formed by advanced directional shotcreting at the top plate position of the roadway cross-section outline to form an advanced fixed shotcreting reinforcement plate 11.

[0031] The primary support unit includes a metal mesh 12, which is arranged on the bottom surface of the pre-spraying reinforcement plate 11 located at the top of the roadway.

[0032] The reinforced support unit includes at least one support module. The support module includes a roof 14, a left support leg 15, and a right support leg 16. The left support leg 15 and the right support leg 16 are located on opposite sides of the roadway, and the bottom ends of the left support leg 15 and the right support leg 16 are connected to the bottom of the roadway. The top end of the left support leg 15 extends toward the side where the right support leg 16 is located to form a first connecting part, and the top end of the right support leg 16 extends toward the side where the left support leg 15 is located to form a second connecting part. One end of the roof 14 is connected to the first connecting part, and the other end of the roof 14 is connected to the second connecting part. The top end of the roof 14 abuts against the metal mesh 12.

[0033] In this embodiment, a multi-stage support structure for soft, thick coal seam roadways is provided. By performing advanced directional shotcreting at the top plate position of the roadway cross-section, an advanced support unit is formed to control the loose roof of the coal seam roadway, enabling rapid tunneling under the advanced fixed shotcreting reinforcement plate 11.

[0034] Specifically, intelligent integrated drilling and grouting equipment is used to construct the tunneling face below the reinforced pre-sprayed grouting reinforcement plate 11, with a slope angle of 45°. The intelligent integrated drilling and grouting equipment includes an integrated drilling rig, a high-pressure grouting pump, a grout supply system, and an intelligent control system. The integrated drilling rig, besides its main body, mainly consists of a hollow drill rod, a grout sealing plug, and a dual-hole grouting drill bit. By drilling to the designed depth, adjusting the direction of the grouting holes, and retracting the drill bit, directional grouting is carried out to form the pre-sprayed grouting reinforcement plate 11. The high-pressure grouting pump can provide a grouting pressure exceeding 20 MPa; the grout supply system can continuously stir, recover, and filter the grouting material; and the intelligent control system can precisely and intelligently control the direction and pressure of the drill nozzles for directional grouting.

[0035] Specifically, the shotcrete material is a coal-affinity cement slurry, which exhibits good wettability, permeability, and bonding strength to the coal seam surface, effectively consolidating fractured coal and rock masses. The shotcrete material comprises three parts: a matrix material, a modifying additive, and functional auxiliaries. The matrix material is P.O52.5 ordinary Portland cement, accounting for approximately 85% of the dry mass; the coal-affinity modifying additive is coal gangue powder, which improves the compatibility between the slurry and the coal mass, reduces interfacial separation, and lowers costs, accounting for approximately 15% of the dry mass; the functional material is a polycarboxylate-based high-efficiency water-reducing agent, which lowers the water-cement ratio and improves the slurry fluidity. The preferred water-cement ratio for the shotcrete material is 1:1.

[0036] Specifically, the hollow drill rod is a single-tube shotcrete drill rod. The two shotcrete holes of the dual-hole shotcrete drill bit are symmetrically distributed on the same cross-section of the drill rod, featuring simple structure, high shotcrete efficiency, and convenient processing. The designed drilling depth is the distance of one advanced reinforcement cycle, preferably designed to be 40 meters. The retraction speed during the fixed-shotcrete process is related to the width of the fixed-shotcrete plate, which is set to 3m wide, with a drill extraction speed of 0.4m / min, resulting in a fixed-shotcrete plate thickness of approximately 30cm. The advanced support unit is an advanced fixed-shotcrete reinforcement plate 11 formed by two overlapping fixed-shotcrete plates.

[0037] Specifically, advanced directional shotcreting is performed at the top slab of the roadway cross-section. First, the first advanced directional shotcreting borehole is drilled, and the first directional shotcreting plate is formed by withdrawing the drill. Then, the drilling rig is moved to drill a second advanced directional shotcreting borehole, and the second directional shotcreting plate is formed by withdrawing the drill. The two directional shotcreting plates are overlapped to form an advanced directional shotcreting reinforcement plate 11. After the advanced directional shotcreting reinforcement plate 11 hardens, a stable advanced support unit is formed. By excavating the roadway under the stable advanced support unit, a "drilling-support" cyclic operation mode can be realized. This ensures that under the protection of the tunneling equipment's roof, the standard procedure of excavating single or even multiple anchor bolt support rows is followed by temporary support, allowing the mechanization advantages of the tunneling equipment to be fully utilized.

[0038] Specifically, the rapid tunneling process refers to tunneling and temporary anchor mesh support using an integrated tunneling and anchoring machine under a stable and pre-reinforced roof. The anchor mesh support consists of anchor bolts (cables) in conjunction with metal mesh 12 for temporary support, i.e., establishing the initial support unit. The metal mesh 12 is arranged on the bottom surface of the pre-sprayed reinforcement plate 11 located at the top of the roadway.

[0039] Specifically, the reinforced support unit comprises multiple support modules, the number of which has been rationally planned according to the length of the roadway. In this application, the preferred distance between two adjacent support modules is 0.8m.

[0040] Specifically, the support module includes a roof 14, a left support leg 15, and a right support leg 16. The left and right support legs 15 and 16 are located on opposite sides of the tunnel. The bottom ends of the left and right support legs 15 and 16 extend into the bottom of the tunnel and are fixed to the tunnel rock strata 10. The top end of the left support leg 15 extends towards the side where the right support leg 16 is located, forming a first connecting portion that supports one end of the roof 14. The top end of the right support leg 16 extends towards the side where the left support leg 15 is located, forming a second connecting portion that supports the other end of the roof 14. This allows the top end of the roof 14 to abut against the metal mesh 12. In this application, the structural design of the support module enables rapid installation, reducing the labor intensity of relevant personnel. Simultaneously, the use of the metal mesh 12 of the initial support unit in conjunction with the support module of the reinforcing support unit further improves support efficiency.

[0041] Furthermore, the initial support unit also includes a first anchor cable 13. One end of the first anchor cable 13 is fixed to the metal mesh 12, and the other end of the first anchor cable 13 passes through the pre-sprayed concrete reinforcement plate 11 and extends into the tunnel rock stratum 10. Multiple first anchor cables 13 are arranged in a grid pattern, with a preferred spacing of 0.8m between adjacent first anchor cables 13. In this application, the length of the first anchor cable 13 is at least 1m longer than the thickness of the pre-sprayed concrete reinforcement plate 11, meaning the anchoring end of the first anchor cable 13 penetrates the tunnel rock stratum 10 to a depth of at least 1m, ensuring that the anchoring section of the first anchor cable 13 can penetrate deep into the tunnel rock stratum 10 to provide stability. If the tunnel rock stratum 10 is soft rock, the first anchor cable 13 is a grouting anchor cable, with grouting reinforcing the tunnel rock stratum 10 above the pre-sprayed concrete reinforcement plate 11 to form a stable anchoring zone. Under the pre-sprayed reinforcement plate 11, a tunneling and anchoring machine was used for rapid tunneling, and temporary anchor mesh support was carried out.

[0042] Furthermore, the support module also includes a second anchor cable 17 and a third anchor cable 18. One end of the second anchor cable 17 is fixed to the left support leg 15, and the other end of the second anchor cable 17 passes through the left support leg 15 and extends into the side wall of the tunnel rock stratum 10, which further stabilizes the left support leg 15 and enhances the stability of the roof 14. One end of the third anchor cable 18 is fixed to the right support leg 16, and the other end of the third anchor cable 18 passes through the right support leg 16 and extends into the side wall of the tunnel rock stratum 10, which further stabilizes the right support leg 16 and enhances the stability of the roof 14.

[0043] Furthermore, a first stepped surface is formed at the top of the first connecting part, and a second stepped surface is formed at the top of the second connecting part, which allows the opposite ends of the canopy 14 to be quickly placed on the first stepped surface and the second stepped surface respectively. One end of the fourth anchor cable 19 of the support module is fixed to the first connecting part, allowing the other end of the fourth anchor cable 19 to pass through the canopy 14 and the pre-sprayed reinforcement plate 11 and extend into the roadway rock stratum 10. Then, one end of the fifth anchor cable 20 of the support module is fixed to the second connecting part, allowing the other end of the fifth anchor cable 20 to pass through the canopy 14 and the pre-sprayed reinforcement plate 11 and extend into the roadway rock stratum 10, further enhancing the stability of the primary support unit and the reinforced support unit, strengthening the overall support strength, and improving support efficiency. In this application, along the width direction of the roadway, the fourth anchor cable 19 and the fifth anchor cable 20 are preferably located between two adjacent rows of first anchor cables 13, which can reduce the interference between the first anchor cables 13, the fourth anchor cable 19, and the fifth anchor cable 20.

[0044] Specifically, the first connecting part and the second connecting part may also be provided with a first assembly structure, and the first connecting part and the second connecting part can be connected to the canopy 14 through the first assembly structure. In this application, the first assembly structure can be a feasible structure such as screws, nuts, or hooks.

[0045] Specifically, the reinforced support unit uses a lightweight, high-strength alloy canopy for permanent support, and this reinforced support unit consists of multiple support modules arranged at intervals. Each support module includes a canopy roof 14, a left canopy leg 15, and a right canopy leg 16. The spacing between adjacent support modules is preferably 0.8m. Between the two rows of first anchor cables 13, the canopy roof 14 and the left canopy leg 15 are locked together by a fourth anchor cable 19, and the canopy roof 14 and the right canopy leg 16 are locked together by a fifth anchor cable 20. The middle section of the canopy roof 14 is held in place by a central anchor cable, ensuring better contact between the canopy roof 14 and the metal mesh 12. The left canopy leg 15 and the right canopy leg 16 are locked together by a second anchor cable 17 and a third anchor cable 18, respectively. The anchoring sections of the second anchor cable 17 and the third anchor cable 18 extend into the sidewall of the tunnel rock stratum 10 and slope downwards into the rock stratum of the tunnel sidewall. The canopy roof 14 is a long plate with a length of 4m, a width of 20cm, and a thickness of 3cm. It can be in close contact with the metal mesh 12, so that the metal mesh 12 can protect the pre-spraying reinforcement plate 11 and play the role of roof protection.

[0046] In some embodiments, the first connecting portion further includes a first connecting segment and a first functional segment. The first connecting segment extends towards the top of the left canopy leg 15, and the top of the first functional segment forms a first stepped surface. The height of the first stepped surface is lower than the height of the top of the first connecting segment. The second connecting portion further includes a second connecting segment and a second functional segment. The second connecting segment extends towards the top of the right canopy leg 16, and the top of the second functional segment forms a second stepped surface. The height of the second stepped surface is lower than the height of the top of the second connecting segment. When the opposite ends of the canopy roof 14 are placed on the first stepped surface and the second stepped surface respectively, the height of the top of the canopy roof 14 is made to be flush with the height of the top of the first connecting segment and the top of the second connecting segment, respectively. This allows the top of the canopy roof 14, the top of the first connecting segment of the first connecting portion, and the top of the second connecting segment of the second connecting portion to simultaneously abut against the metal mesh 12, further reducing the length of the left canopy leg 15 and the right canopy leg 16, and also improving the support efficiency of the support module.

[0047] In summary, by performing pre-directional shotcreting at the roof position of the roadway cross-section, pre-support units are formed to control the loose roof of the coal seam roadway, enabling rapid tunneling under the pre-directed shotcreting reinforcement plate; and by using the primary support unit in conjunction with the reinforced support unit, it is easy to install quickly, thereby reducing labor intensity and further improving support efficiency.

[0048] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention.

[0049] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A multi-stage support structure for roadways in soft, thick coal seams, characterized in that, include: The advanced support unit is formed by advanced directional shotcreting at the top plate position of the roadway cross-section outline to create an advanced fixed shotcrete reinforcement plate. The primary support unit includes a metal mesh, which is arranged on the bottom surface of the pre-sprayed reinforcement plate located at the top of the roadway. The reinforced support unit includes at least one support module. Each support module includes a roof, a left support leg, and a right support leg. The left and right support legs are located on opposite sides of the roadway, and their bottom ends are connected to the bottom of the roadway. The top end of the left support leg extends towards the side where the right support leg is located to form a first connecting portion, and the top end of the right support leg extends towards the side where the left support leg is located to form a second connecting portion. One end of the roof is connected to the first connecting portion, and the other end of the roof is connected to the second connecting portion. The top end of the roof abuts against the metal mesh. The initial support unit also includes a first anchor cable, one end of which is fixed to a metal mesh, and the other end of which passes through the pre-spraying reinforcement plate and extends into the roadway rock strata. The advanced fixed-point spraying reinforcement plate is formed by overlapping a first fixed-point spraying plate and a second fixed-point spraying plate, which are formed by advanced directional spraying at the top plate position of the roadway cross-section outline.

2. The multi-stage support structure for soft, thick coal seam roadways as described in claim 1, characterized in that, The anchoring end of the first anchor cable penetrates into the rock strata of the roadway to a depth of not less than 1m.

3. The multi-stage support structure for soft, thick coal seam roadways as described in claim 1, characterized in that, The top end of the first connecting part has a first stepped surface, the top end of the second connecting part has a second stepped surface, and the opposite ends of the canopy are respectively placed on the first stepped surface and the second stepped surface.

4. The multi-stage support structure for soft, thick coal seam roadways as described in claim 3, characterized in that, The first connecting part includes a first connecting segment and a first functional segment. The first connecting segment extends toward the top of the left canopy leg toward the first functional segment. The top of the first functional segment has a first stepped surface, and the height of the first stepped surface is lower than the height of the top of the first connecting segment. The second connecting part includes a second connecting segment and a second functional segment. The second connecting segment extends toward the top of the right canopy leg toward the second functional segment. The top of the second functional segment forms a second stepped surface. The height of the second stepped surface is lower than the height of the top of the second connecting segment. When the two opposite ends of the canopy are placed on the first step surface and the second step surface respectively, the height of the top of the canopy is level with the height of the top of the first connecting segment and the top of the second connecting segment respectively.

5. The multi-stage support structure for soft, thick coal seam roadways as described in claim 4, characterized in that, The support module also includes a second anchor cable and a third anchor cable. One end of the second anchor cable is fixed to the left support leg, and the other end of the second anchor cable passes through the left support leg and extends into the side wall of the tunnel rock stratum. One end of the third anchor cable is fixed to the right support leg, and the other end of the third anchor cable passes through the right support leg and extends into the side wall of the tunnel rock stratum.

6. The multi-stage support structure for soft, thick coal seam roadways as described in claim 3 or 4, characterized in that, The support module also includes a fourth anchor cable and a fifth anchor cable. One end of the fourth anchor cable is fixed to the first connecting part, and the other end of the fourth anchor cable passes through the roof and the pre-spraying reinforcement plate and extends into the roadway rock strata. One end of the fifth anchor cable is fixed to the second connecting part, and the other end of the fifth anchor cable passes through the roof and the pre-spraying reinforcement plate and extends into the roadway rock strata.

7. The multi-stage support structure for soft, thick coal seam roadways as described in claim 6, characterized in that, The first anchor cable has multiple first anchor cables, which are arranged in a grid pattern; Along the width of the tunnel, the fourth and fifth anchor cables are located between two adjacent columns of the first anchor cables.

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