Roadway supporting system

Abstract

The roadway supporting system comprises a roadway and a freezing piece, the roadway comprises a top plate, a bottom plate and a side wall, the top plate and the bottom plate are oppositely arranged at intervals in the vertical direction, the upper end and the lower end of the side wall are connected with the top plate and the bottom plate respectively, and an installation hole is formed in the top plate. At least part of the mounting hole is located above a to-be-tunneled coal body in the roadway, a freezing medium is arranged in the freezing piece, the freezing piece is arranged in the mounting hole in a penetrating mode, and the freezing piece is used for freezing a rock stratum around the mounting hole to form a freezing layer so that the to-be-tunneled coal body can be excavated after the rock stratum around the mounting hole is completely frozen. The roadway supporting system has the advantages of being simple in structure, good in waterproof performance and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of underground mine development, in particular to a tunnel support system. Background Art

[0002] Tunnel excavation is the prerequisite for coal mining. At present, the serious imbalance of mining and excavation caused by low excavation efficiency, high labor force and low intelligence level seriously restricts the efficient mining of coal in my country. With the gradual depletion of shallow coal resources, the mining depth of coal mines is getting deeper and deeper, and the stress of surrounding rock in the bottom tunnel increases with the increase of mining depth.

[0003] In the relevant technologies, when encountering surrounding rock with water-rich fissures, the roof will collapse and water seepage will be serious, and the problems of deflection and roof collapse will be prominent, which will seriously affect the normal operations such as tunnel excavation and anchor support and the safety of the operators. The time spent on strengthening roof maintenance and anchor support will increase, and it is strictly forbidden to affect the tunnel excavation operation and limit the excavation efficiency and construction safety. Utility Model Content

[0004] The utility model aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the utility model proposes a tunnel support system that prevents water leakage, has high construction efficiency and is low in cost.

[0006] The tunnel support system according to the embodiment of the utility model includes: a tunnel, the tunnel includes a roof, a bottom plate and side walls, the top plate and the bottom plate are arranged opposite to each other in the up-down direction, and the upper and lower ends of the side walls are respectively connected to the top plate and the bottom plate, the top plate is provided with a mounting hole, at least a part of the mounting hole is located above the coal body to be excavated in the tunnel; a freezing element, the freezing element has a freezing medium and is penetrated in the mounting hole, the freezing element is used to freeze the rock layer around the mounting hole to form a freezing layer, so as to excavate the coal body to be excavated after the rock layer around the mounting hole is completely frozen.

[0007] The tunnel support system of the embodiment of the utility model is provided with installation holes and freezing parts. The freezing parts are used to freeze the roof area to be anchored, thereby blocking water seepage from the roof, enhancing the stability of the roof, and improving the properties of the roof surrounding rock. It effectively solves the problems of roof caving and water seepage commonly seen in traditional tunnel excavation, significantly improves the tunnel excavation efficiency, and ensures the safety of anchor support construction.

[0008] In some embodiments, the freezing member is a freezing pipe, which is inserted into the mounting hole, and the freezing medium is liquid nitrogen which is passed into the freezing pipe so as to freeze the rock formation around the mounting hole.

[0009] In some embodiments, the tunnel support system further includes a thermometer, which is disposed in the roof and is used to measure the temperature of the roof.

[0010] In some embodiments, the mounting hole extends from bottom to top and is inclined toward the direction of the coal body to be excavated.

[0011] In some embodiments, the mounting hole comprises a plurality of freezing holes, and the plurality of freezing holes are arranged at intervals along the width direction of the tunnel, at least part of the freezing holes are located above the coal body to be excavated, and there are a plurality of freezing parts, and the plurality of freezing parts are arranged one by one in the plurality of freezing holes.

[0012] In some embodiments, the installation hole further comprises a plurality of grouting holes, the plurality of grouting holes are located on a side of the freezing hole away from the coal body to be excavated, and the grouting holes are suitable for installing anchor rods and grouting.

[0013] In some embodiments, the tunnel support system further includes a connecting piece, which passes through the frozen layer and is arranged in a crack in the rock formation above the frozen layer, so that the connecting piece can lead water out of the crack in the rock formation.

[0014] In some embodiments, the tunnel support system also includes a water guide groove, which is arranged in the tunnel and extends along the length direction of the tunnel. The connecting piece is connected to the water guide groove so that water in the rock formation fissures flows into the water guide groove through the connecting piece.

[0015] In some embodiments, the connecting piece includes a first tube and a plurality of second tubes, the first tube extending along the length direction of the tunnel and being arranged on the top plate, the second tubes being arranged at intervals along the length direction of the tunnel and one end of the second tube passing through the frozen layer and being arranged in the rock formation cracks, the other end of the second tube being connected to the first tube and the first tube being connected to the water guide trough, so that water above the frozen layer is introduced into the water guide trough through the first tube and the plurality of second tubes.

[0016] In some embodiments, the tunnel support system further comprises a metal mesh, which is located in the tunnel and arranged on the roof. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a tunnel support system according to an embodiment of the utility model.

[0018] Figure 2 It is a schematic diagram of the installation of the tunnel support system of the embodiment of the utility model.

[0019] Figure 3It is a schematic structural diagram of the connecting parts of the tunnel support system of the embodiment of the utility model.

[0020] Tunnel support system 100;

[0021] Top plate 1; mounting hole 11; freezing layer 12; grouting layer 13; anchor rod 2; connecting piece 3; first pipe 31; second pipe 32. DETAILED DESCRIPTION

[0022] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but cannot be understood as limiting the present invention.

[0023] The tunnel support system 100 according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0024] like Figure 1-Figure 3 As shown, the tunnel support system 100 according to the embodiment of the present utility model includes a tunnel and a freezing component (not shown in the figure).

[0025] The tunnel includes a roof 1, a bottom plate and side walls, the roof 1 and the bottom plate are arranged opposite to each other in the vertical direction, and the upper and lower ends of the side walls are connected to the roof 1 and the bottom plate respectively, and a mounting hole 11 is provided on the roof 1, and at least part of the mounting hole 11 is located above the coal body to be excavated in the tunnel. Specifically, Figure 1 and Figure 2 As shown, the side wall includes a front side wall and a rear side wall, the upper and lower ends of the front side wall are respectively connected to the front side of the top plate 1 and the front side of the bottom plate, and the upper and lower ends of the rear side wall are respectively connected to the rear side of the top plate 1 and the rear side of the bottom plate, so that the tunnel forms a closed area, and the mounting hole 11 extends upward from the top plate 1, and a part of the mounting hole 11 is located above the coal body to be excavated.

[0026] The freezing element has a freezing medium therein and is disposed in the installation hole 11. The freezing element is used to freeze the rock layer around the installation hole 11 to form a freezing layer 12, so that the coal body to be excavated can be excavated after the rock layer around the installation hole 11 is completely frozen. Figure 1-Figure 2 As shown, the freezing element is fixedly installed in the installation hole 11, and the freezing element is used to cool the rock layer around the installation hole 11 so that the rock layer around the installation hole 11 is frozen, so that a frozen layer 12 is formed in the tunnel roof 1, and the water in the overlying rock layer cannot penetrate the frozen layer 12. Therefore, through the freezing treatment, the water seepage channel of the roof 1 is cut off, the mechanical properties of the surrounding rock of the roof 1 are enhanced, and the roof 1 is effectively prevented from caving and water seepage. The stable environment of the roof 1 provides a strong guarantee for the subsequent excavation operation, ensuring that there will be no water seepage and leakage of the roof 1 during the excavation operation, improving the excavation operation environment, reducing the shutdown and rework caused by the instability of the roof 1, and improving the tunnel excavation efficiency.

[0027] The tunnel support system of the embodiment of the utility model is provided with mounting holes 11 and freezing parts, which freeze the area of ​​the roof 1 to be anchored by the freezing parts, thereby blocking water seepage of the roof 1, enhancing the stability of the roof 1, and improving the surrounding rock properties of the roof 1. It effectively solves the problems of roof 1 caving and water seepage commonly seen in traditional tunnel excavation, significantly improves the tunnel excavation efficiency, and ensures the safety of the anchor rod 2 support construction.

[0028] In some embodiments, the freezing member is a freezing pipe, which is inserted into the mounting hole 11, and the freezing medium is liquid nitrogen which is passed into the freezing pipe so as to freeze the rock formation around the mounting hole 11. Specifically, the freezing pipe is inserted into the mounting hole 11, and liquid nitrogen is passed into the mounting hole 11 so that the liquid nitrogen cools and freezes the rock formation around the mounting hole 11 through the freezing pipe.

[0029] In some embodiments, the tunnel support system 100 further includes a thermometer (not shown in the figure), which is disposed in the roof 1 and adjacent to the freezing element, and is used to measure the temperature of the roof 1. Specifically, the thermometer is disposed in the roof 1 and adjacent to the freezing element, and the temperature in the rock layer of the roof 1 is measured by the thermometer. When the freezing temperature is greater than a preset value, it indicates that the rock layer of the roof 1 is completely frozen, and the excavation area to be excavated can be carried out to excavate the coal body to be excavated.

[0030] In some embodiments, the mounting hole 11 extends from bottom to top and is inclined toward the direction of the coal body to be excavated. Figure 1 and Figure 2 As shown, the installation hole 11 is drilled upward from the bottom of the top plate 1 and inclined toward the direction of the coal body to be excavated, thereby ensuring that the installation hole 11 is located at the upper part of the coal body to be excavated, and further ensuring that the freezing range is located at the upper part of the coal body to be excavated.

[0031] In some embodiments, the installation hole 11 includes a plurality of freezing holes, which are arranged at intervals along the width direction of the tunnel, at least part of the freezing holes is located above the coal body to be excavated, and there are multiple freezing parts, which are arranged in a one-to-one correspondence in the multiple freezing holes. Specifically, the freezing holes are arranged at equal intervals along the front-to-back direction, the number of freezing holes and the number of freezing parts are both multiple, and each freezing hole is provided with a freezing part, thereby ensuring that the frozen layer 12 covers the entire tunnel roof 1, and ensuring the freezing effect and freezing efficiency of the roof 1.

[0032] In some embodiments, the installation hole 11 further includes a plurality of grouting holes, which are located on the side of the freezing hole away from the coal body to be excavated, and the grouting holes are suitable for installing the anchor rod 2 and grouting. Figure 1As shown, the mounting hole 11 can be a freezing hole and a grouting hole. When the mounting hole 11 is located above the coal body to be excavated and the roof 1 needs to be frozen, the mounting hole 11 is a freezing hole, and the freezing part can be inserted into the freezing hole. After the coal body to be excavated, the mounting hole 11 is located on the left side of the new coal body to be excavated. The mounting hole 11 can be a grouting hole, and the freezing part is taken out from the mounting hole 11, and the anchor rod 2 is driven into the mounting hole 11 and the mounting hole 11 is grouting. The stability of the roof 1 is further enhanced by the anchor rod 2 and grouting, and the problems such as fissure water leakage in the later stage are prevented. Therefore, the dual function design of the mounting hole 11 (freezing hole and grouting hole) not only simplifies the construction process, but also improves the construction efficiency and safety.

[0033] In some embodiments, the tunnel support system 100 further includes a connecting piece 3, which passes through the frozen layer 12 and is disposed in the rock stratum fissure above the frozen layer 12, so that the connecting piece 3 can lead water in the rock stratum fissure out. Figure 3 As shown, in order to reasonably guide the fissure water in the rock layer of the roof 1, after the tunnel section is excavated, before the anchor 2 is grouted, the frozen layer 12 can be drilled, and then the connecting piece 3 can be passed through the hole to connect with the fissure in the rock layer of the inner roof 1, so that the water above the frozen layer 12 can be discharged through the connecting piece 3. If the fissure water in the rock layer of the roof 1 accumulates too much, it will cause the water pressure to increase, thereby exerting additional pressure on the roof 1. The connecting piece 3 can lead the fissure water out by penetrating the frozen layer 12 to reduce the water pressure of the roof 1. In addition, high water pressure may cause the surrounding rock to soften or expand, and then cause the roof 1 to sink, deflect, and other problems. The connecting piece 3 can effectively drain the accumulated water and maintain the stability of the surrounding rock. Finally, the presence of water may weaken the bonding force between the anchor 2 and the surrounding rock, causing the anchor 2 to fail. The water can be discharged through the connecting piece 3 to ensure the anchoring effect of the anchor 2 after grouting, and improve the reliability of the support system.

[0034] In some embodiments, the tunnel support system 100 further includes a water guide groove (not shown in the figure), which is arranged in the tunnel and extends along the length direction of the tunnel, and the connecting piece 3 is connected to the water guide groove, so that water in the rock formation fissure flows into the water guide groove through the connecting piece 3. Specifically, the water guide groove is arranged at the bottom of the tunnel and extends in the left-right direction, and the lower end of the connecting piece 3 is connected to the water guide groove, so that the water in the rock formation fissure flows into the water guide groove through the connecting piece 3, and then flows out of the tunnel through the water guide groove.

[0035] In some embodiments, the connecting member 3 includes a first tube 31 and a plurality of second tubes 32, the first tube 31 extends along the length direction of the tunnel and is arranged on the tunnel roof 1, the second tubes 32 are arranged at intervals along the length direction of the tunnel, and one end of the second tube 32 passes through the frozen layer 12 and is arranged in the rock stratum crack, and the other end of the second tube 32 is connected to the first tube 31 and the first tube 31 is connected to the water guide groove, so that the water above the frozen layer 12 is introduced into the water guide groove through the first tube 31 and the plurality of second tubes 32. Specifically, as Figure 3 As shown, the first tube 31 is a horizontal tube extending in the left-right direction and is fixed on the tunnel roof 1 by fasteners, and there are multiple second tubes 32, and the multiple second tubes 32 extend in the up-down direction, and the upper ends of the second tubes 32 pass through the frozen layer 12 and extend into the rock cracks, and the lower ends of the second tubes 32 are connected to the first tube 31, and the first tube 31 is connected to the water guide groove, so that the water in the rock cracks flows into the water guide groove through the first tube 31 and the second tube 32.

[0036] In some embodiments, the tunnel support system 100 further includes a metal mesh (not shown in the figure), which is located in the tunnel and arranged on the roof 1. Specifically, when the coal body to be excavated is completely excavated, the metal mesh can be laid on the roof 1 of the excavation section to prevent deviation and roof collapse, thereby ensuring the safety of the operators.

[0037] The working process of the tunnel roof system 1 of the utility model embodiment is as follows:

[0038] S1: Determination and analysis of rock mechanical parameters of surrounding rock and roof 1.

[0039] S2: Determine the height H of the top plate 1 that needs to be frozen and grout-anchored according to the rock mechanical properties of the top plate 1 rock layer and the water seepage and leakage conditions.

[0040] S3: Determine the freezing and grouting anchoring range, the freezing radius R1, the grouting radius R2, then determine the freezing-grouting anchoring radius R, and R is the minimum value between R1 and R2, to ensure that the determined operating range can be covered by the freezing operation and the anchoring operation (for example: taking the freezing radius R1 as greater than the grouting radius R2 as an example, take the smaller value R2, then determine the freezing-anchoring radius R as R2).

[0041] S3: Drill holes in the roof to form installation holes 11, and the holes are axially along the tunnel and inclined toward the heading direction to ensure that the frozen layer 12 is above the coal body to be excavated, and that the excavation operation is within the freezing range of the roof 1, so that the surrounding rock characteristics of this part of the roof 1 are improved to ensure the safety of the operators. And because the frozen layer 12 forms an isolation layer, the water in the overlying rock layer cannot penetrate the frozen layer 12, thereby ensuring that there will be no water seepage or leakage in the roof 1 during the excavation operation, and improving the excavation operation environment.

[0042] S4: Design the drilling angle and depth, and determine the drilling arrangement and density considering the freezing range and the grouting diffusion anchoring range to ensure that the freezing layer 12 and the grouting diffusion anchoring range can be connected as a whole to form a continuous anchoring area.

[0043] S5: After the freezing and grouting anchoring design scheme is determined, a hole is drilled into the roof 1 of the coal body to be excavated, a freezing pipe is inserted, and a freezing medium is injected to form a frozen part, and the roof 1 is waited for freezing.

[0044] S6: Install a thermometer at the boundary of the predetermined freezing range to monitor the freezing temperature and freezing effect. The thermometer can be installed in the freezing drilled hole in the previous step, or placed on the surface of the top plate 1 at the boundary of the predetermined freezing range.

[0045] S7: When the temperature of the thermometer reaches the set temperature, the edge of the predetermined freezing layer 12 reaches the set freezing effect, that is, the freezing layer 12 of the operation cycle reaches the designed freezing effect, and the thermometer is withdrawn. The thermometer can be reused many times.

[0046] S8: Perform tunnel boring machine cutting operations and tunnel excavation in the area below the frozen layer 12 to excavate a complete tunnel section.

[0047] S9: After the tunnel excavation is completed, the freezing pipe is withdrawn, and the cycle freezing operation is completed. The freezing pipe and freezing materials can be reused many times.

[0048] S10: Lay a metal mesh on the top plate 1 of the excavation section to prevent deviation and roof collapse and ensure the safety of workers.

[0049] It is worth noting that: 1. In order to reasonably drain the water in the rock fissures of the roof 1, after the tunnel section excavation is completed and before the anchor rod 2 is grouted, holes can be drilled through the anchor layer, and connecting pieces 3 and water guide grooves can be set. The connecting pieces 3 lead from the roof 1 to the rock fissures above the roof 1, and then lead from the side to the floor water guide groove.

[0050] 2. Install the hollow grouting anchor rod 2 in the installation hole 11. Since the installation hole 11 has been drilled in the aforementioned freezing operation and the freezing pipe has been withdrawn from the installation hole 11, the installation hole 11 can be used as a second hole for the anchor rod 2, reducing the amount of drilling operations.

[0051] 3. The tail of anchor rod 2 is used to perform grouting operations, install trays, pre-tighten nuts and other anchoring operations through the hollow grouting holes of anchor rod 2, so that the pre-tightening force of anchor rod 2 reaches the set state.

[0052] 4. To verify the grouting range and anchoring effect of the grouting layer 13, core drilling can be performed at the midpoint of the line connecting the two anchor rods 2, i.e., the anchoring boundary or overlapping area, to detect the grouting anchoring effect.

[0053] 5. Anchor rods 2 or anchor cables can be added after excavation to enhance the support effect. At this time, freezing operations, anchoring operations, and adding anchor rods 2 or anchor cables can be carried out simultaneously, reducing the time used for a single cycle of tunnel excavation and anchoring operations and improving tunnel excavation efficiency.

[0054] The advantages of the tunnel support system 100 of the embodiment of the utility model are as follows:

[0055] 1. The mounting hole 11 is the hole for drilling the anchor rod 2, which reduces the drilling construction workload.

[0056] 2. The rock properties of the roof 1 are improved by freezing, the temperature of the roof 1 is lowered, and a frozen layer 12 is formed to prevent water leakage and seepage of the roof 1, thereby completing temporary support.

[0057] 3. The rock properties of the roof 1 are improved by grouting, and the slurry diffuses into the cracks of the roof 1 to form a complete grouting layer 13, thereby preventing water leakage and seepage of the roof 1 and completing permanent support.

[0058] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0059] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0060] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0061] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0062] In the present utility model, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0063] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A tunnel support system, characterized in that: include: A tunnel, the tunnel comprising a roof, a bottom plate and side walls, the roof and the bottom plate being arranged opposite to each other in an up-down direction, and the upper and lower ends of the side walls being connected to the roof and the bottom plate respectively, the roof being provided with a mounting hole, and at least a part of the mounting hole being located above the coal body to be excavated in the tunnel; A freezing member having a freezing medium therein and penetrating the mounting hole, wherein the freezing member is used to freeze the rock layer around the mounting hole to form a freezing layer, so as to excavate the coal body to be excavated after the rock layer around the mounting hole is completely frozen.

2. The tunnel support system according to claim 1, characterized in that: The freezing member is a freezing pipe, which is inserted into the installation hole. The freezing medium is liquid nitrogen which is passed into the freezing pipe so as to freeze the rock formation around the installation hole.

3. The tunnel support system according to claim 1, characterized in that: It also includes a thermometer, which is disposed inside the top plate and is used to measure the temperature of the top plate.

4. The tunnel support system according to claim 1, characterized in that: The installation hole extends from bottom to top and is inclined toward the direction of the coal body to be excavated.

5. The tunnel support system according to claim 1, characterized in that: The installation hole includes a plurality of freezing holes, which are arranged at intervals along the width direction of the tunnel, at least part of the freezing holes are located above the coal body to be excavated, and there are a plurality of freezing parts, which are arranged in a one-to-one correspondence in the plurality of freezing holes.

6. The tunnel support system according to claim 5, characterized in that: The installation hole also includes a plurality of grouting holes, which are located on a side of the freezing hole away from the coal body to be excavated, and the grouting holes are suitable for installing anchor rods and grouting.

7. The tunnel support system according to claim 1, characterized in that: It also includes a connecting piece, which passes through the frozen layer and is arranged in the rock stratum fissure above the frozen layer, so that the connecting piece can lead out the water in the rock stratum fissure.

8. The tunnel support system according to claim 7, characterized in that: It also includes a water guide groove, which is arranged in the tunnel and extends along the length direction of the tunnel. The connecting piece is connected to the water guide groove so that water in the rock formation cracks can flow into the water guide groove through the connecting piece.

9. The tunnel support system according to claim 8, characterized in that: The connecting piece includes a first tube and a plurality of second tubes, the first tube extending along the length direction of the tunnel and being arranged on the top plate, the second tubes being arranged at intervals along the length direction of the tunnel and one end of the second tube passing through the frozen layer and being arranged in the cracks of the rock formation, the other end of the second tube being connected to the first tube and the first tube being connected to the water guide groove, so that water above the frozen layer is introduced into the water guide groove through the first tube and the plurality of second tubes.

10. The tunnel support system according to claim 1, characterized in that: It also includes a metal mesh, which is located in the tunnel and arranged on the top plate.

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