Advanced support combined with negative Poisson's ratio structural slab filling and construction method thereof

Abstract

The invention discloses a forepoling combined with negative Poisson's ratio structural slab filling and a construction method of the forepoling, and relates to the technical field of mining roadway supporting. The advanced support comprises a U-shaped steel arch frame, negative Poisson's ratio structural plates, feet-lock bolts and advanced steel pipes, the construction method comprises the steps that the U-shaped steel arch frame is spliced and assembled on site according to design requirements, then a gap between the steel arch frame and an actual excavation boundary is obtained through a multi-purpose underground space three-dimensional scanner, and the number of the negative Poisson's ratio structural plates needing to be filled is calculated; the negative Poisson's ratio structural slabs are fixed to the supporting edge of the U-shaped steel arch frame through an acrylate adhesive, the adjacent structural slabs are connected through the acrylate adhesive, and then the U-shaped steel arch frame is installed in an area needing to be supported to complete supporting; the supporting problems that in the prior art, a U-shaped steel arch frame is short in service life, poor in supporting effect, large in deformation and ineffective, large in field operation potential safety hazard and the like are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of mining tunnel support, and in particular relates to an advanced support combined with negative Poisson's ratio structural plate filling and a construction method thereof. Background Art

[0002] Due to the promotion and use of backfill mining in underground mines, the recovery of pillars or residual ore under the condition of backfill body wrapping has become a common problem faced by many mines in the later stage. In order to recover such ore bodies, some mining and cutting projects have to be arranged in the backfill body of the adjacent backfilled mining area, which brings great safety hazards to tunnel excavation and support. For the support of tunnels in such backfill bodies, advanced support technologies such as advanced steel pipe and U-shaped steel arch frame combined support and advanced pipe shed support are generally used. Such advanced support technologies need to cooperate with U-shaped steel arch frame to play a supporting role, but when excavating the tunnel, over-excavation and under-excavation are inevitable, which leads to deviations between the actual excavation section profile and the designed section profile, resulting in point support in the under-excavation area when the U-shaped steel arch frame is supported, resulting in large stress concentration; while in the over-excavation area, the entity is not supported and no actual support is played on the tunnel. Such low-quality support not only greatly shortens the service life of the U-shaped steel arch frame and increases the support cost, but also brings great safety hazards to the safety of operations in the tunnel.

[0003] In view of this, it is necessary to improve the existing U-shaped steel arch support technology to improve the support effect, support life, reduce support costs, and ensure safe production. Summary of the invention

[0004] In view of the above technical problems, the present invention provides an advanced support combined with negative Poisson's ratio structural plate filling and a construction method thereof, which mainly solves the over-under excavation phenomenon existing in the actual excavation section in the tunneling project. When ordinary U-shaped steel arch frame support is used, the local stress concentration area in the under-excavation area of ​​the tunnel and the over-excavation area fail to effectively support the surrounding rock entity, which causes the U-shaped steel arch frame to have a short life, poor support effect, large deformation failure of the arch frame, and great safety hazards in on-site operations. The construction method is based on the advanced support technology of combined support of advanced steel pipes and U-shaped steel arch frames, combined with filling negative Poisson's ratio structural plates to improve the support effect.

[0005] The present invention provides an advanced support combined with negative Poisson's ratio structural plate filling, which adopts the following technical solutions: An advance support combined with negative Poisson's ratio structural plate filling, comprising a negative Poisson's ratio structural plate, a U-shaped steel arch frame, an advance steel pipe and a locking foot anchor rod; The U-shaped steel arch frame is erected in the over-excavation area, the U-shaped steel arch frame connects the locking foot anchor rod and the bottom base, and the top of the U-shaped steel arch frame is arranged with an advanced steel pipe; The gap between the U-shaped steel arch frame and the boundary of the over-excavation area is filled with a negative Poisson's ratio structural plate; the negative Poisson's ratio structural plate is fixed to the edge of the U-shaped steel arch frame by an acrylic adhesive, the negative Poisson's ratio structural plate is arranged in a layered stacking manner according to the volume of the over-excavation area, and the negative Poisson's ratio structural plates are bonded and connected by acrylic adhesive.

[0006] Preferably, the negative Poisson's ratio structural plate includes a plurality of rigid circular node units, and the rigid circular node units are connected by fiber lines.

[0007] Preferably, the rigid circular node units are spheres with a radius of 1.5 cm, the spheres are connected by fiber lines, and the negative Poisson's ratio structural plate includes five layers of rigid circular node units, and the five layers of rigid circular node units are arranged in a "5-4-5-4-5" structural combination.

[0008] Preferably, the rigid circular node unit is made of PVC material, POM material or PET material.

[0009] The present invention also provides a construction method for advanced support combined with negative Poisson's ratio structural plate filling, and the construction steps are as follows: S1. Use a tunneling trolley to construct the mining tunnel according to the cross-sectional dimensions required by the design. After a single advance, use a trackless scraper to carry out the mine; S2. Clean the ground gravel and deal with the loose stones on the roof of the mining tunnel after mining. Perform secondary treatment on the under-excavated area of ​​the cross-section contour to create conditions for the subsequent erection of the U-shaped steel arch frame to ensure the safety of the operation; S3. Assemble and weld the U-shaped steel arch frame in advance, and use a multi-purpose underground space 3D scanner to scan the actual excavation boundary contour in the area that needs to be supported in the mining tunnel. The volume of the gap between the U-shaped steel arch frame and the actual excavation contour is obtained by scanning, and the number of negative Poisson's ratio structural plates required to fill the gap is calculated according to the size of the negative Poisson's ratio structural plates; S4, fixing the negative Poisson's ratio structural plate to the over-excavation area corresponding to the outer edge of the U-shaped steel arch frame by using acrylic adhesive, and adding negative Poisson's ratio structural plates in a layered stacking manner according to the volume of the void in the over-excavation area, and the negative Poisson's ratio structural plates are also bonded and connected by using acrylic adhesive; S5, erecting the U-shaped steel arch frame to which the negative Poisson's ratio structural plate has been fixed corresponding to the over-excavation area, so that the negative Poisson's ratio structural plate fills the gap in the over-excavation area; S6. Finally, using the erected U-shaped steel arch frame as a fulcrum, drive an advance steel pipe diagonally forward along the roof of the mining tunnel, and combine the U-shaped steel arch frame to complete the advance support.

[0010] Preferably, in step S1, during the excavation of the mining tunnel, smooth blasting is used to make the excavation contour as smooth and flat as possible, thereby reducing the workload of secondary contour processing in the later stage and creating good conditions for filling the negative Poisson's ratio structural plate.

[0011] Preferably, in step S3, the multi-purpose underground space three-dimensional scanner turns on the power of the scanning head in the empty area, and through control, 360° laser scanning without blind spots can be achieved, and the actual excavation contour boundary can be accurately obtained.

[0012] Preferably, in step S4, the acrylic adhesive has a fast curing speed, can adapt to harsh and extreme environments, and has high shear strength, peel strength and impact resistance; it can not only achieve a firm bond between the negative Poisson's ratio structural plate and the U-shaped steel arch frame, but also can tightly combine adjacent negative Poisson's ratio structural plates, and form the negative Poisson's ratio structural plates filled in the gap into a whole, giving full play to the negative Poisson's ratio effect.

[0013] Preferably, in step S5, a U-shaped steel arch frame is erected every 1-1.2 m, and the U-shaped steel arch frames are connected by steel plates made of 14# channel steel, and the longitudinal spacing of the connecting steel plates is 0.5-0.6 m; the leg sockets of the U-shaped steel arch frame are dug down 100-200 mm to the solid bottom, which makes the bottom of the U-shaped steel arch frame more firmly erected on the one hand, and on the other hand, the base excavated according to the size of the support legs is coupled with the support legs in a wedge-shaped structure, which also plays a fixing role; locking foot anchor rods are installed at a distance of 1-1.2 m from the support legs to the bottom plate to further fix the U-shaped steel arch frame; finally, the left and right sides of the U-shaped steel arch frame are reconnected and fixed on the bottom plate using steel bars of 14# channel steel to complete the installation of the U-shaped steel arch frame.

[0014] Preferably, in step S6, after the U-shaped steel arch frame is installed, an advance steel pipe is installed on the top of the U-shaped steel arch frame. The advance steel pipe is a φ32mm thin-walled steel pipe, 2m long, installed at an elevation angle of 5°, and the spacing between the advance steel pipes is 200mm, ultimately forming an advance support under negative Poisson's ratio structural plate filling.

[0015] Beneficial effects of the present invention: The present invention introduces a negative Poisson's ratio structural plate, which makes full use of the mechanical properties of the negative Poisson's ratio structure. When the negative Poisson's ratio material is subjected to axial tension (or compression), it has the mechanical property of expansion (or contraction) in the vertical direction. This negative Poisson's ratio effect makes the negative Poisson's ratio material have good impact resistance, fracture resistance, energy absorption and vibration isolation performance. The negative Poisson's ratio structural plate is filled into the over-excavation area to make it a buffer layer between the upper filling body and the U-shaped steel arch frame. On the one hand, when the filling body gradually deforms due to the creep effect, the negative Poisson's ratio structural plate is subjected to the pressure applied by the filling body and deforms, exerting the negative Poisson's ratio effect, allowing the upper filling body to deform to a certain extent, avoiding the stress concentration caused by the traditional rigid U-shaped steel arch frame support; on the other hand, when the adjacent mining area is blasting, the negative Poisson's ratio structural plate can absorb a part of the blasting stress wave, preventing the filling body and the U-shaped steel arch frame from being directly subjected to the disturbance of the blasting stress wave and causing instability.

[0016] Compared with other shapes, the rigid circular spheres constituting the negative Poisson's ratio structural plate in the present invention can better fit the outer edge of the U-shaped steel arch frame, and can better adapt to the boundary within the over-excavation area; and the material of the negative Poisson's ratio structural plate is selected from PVC, POM or PET, which has high strength, good toughness and low cost. The material is light, easy to produce and transport, and easy to install, and will not bring cumbersome operation procedures to on-site operations.

[0017] In summary, the advanced support combined with negative Poisson's ratio structural plate filling of the present invention can improve the stability of the filling body, extend the service life of the support facilities, save support costs, and ensure the safety of underground operations by fully utilizing the mechanical properties of the negative Poisson's ratio structural plate; in addition, the use of negative Poisson's ratio materials as new materials in mines conforms to the development trend of innovative mine construction, and the characteristics of low material cost, light weight, and easy processing are in line with the development strategy of reducing costs and increasing efficiency in mines, and can be promoted for use in mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] For ease of explanation, the present invention is described in detail with reference to the following specific implementations and the accompanying drawings.

[0019] Figure 1 The main view of the advance support combined with negative Poisson's ratio structural plate filling; Figure 2 for Figure 1 Lateral section at middle II-II; Figure 3 Schematic diagram of negative Poisson's ratio structural plate and connection between structural plates; Figure 4 Schematic diagram of the connection between the negative Poisson's ratio structural plate and the U-shaped steel arch frame.

[0020] In the figure: 1- negative Poisson's ratio structural plate; 2- U-shaped steel arch; 3- advanced steel pipe; 4- filling body; 5- body to be mined; 6- base pad; 7- bottom base; 8- rigid circular node unit; 9- fiber line. DETAILED DESCRIPTION

[0021] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments; in the following description, specific details such as specific configurations and components are provided only to help fully understand the embodiments of the present invention. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. In addition, for the sake of clarity and brevity, the description of known functions and structures is omitted.

[0022] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0023] like Figure 1-Figure 4 As shown, an advance support combined with negative Poisson's ratio structural plate filling provided in this embodiment includes a negative Poisson's ratio structural plate 1, a U-shaped steel arch frame 2, an advance steel pipe 3 and a locking foot anchor rod (not shown in the figure); the U-shaped steel arch frame 2 is erected in the over-excavation area, the U-shaped steel arch frame 2 is connected to the locking foot anchor rod and the bottom base 7, the advance steel pipe 3 is arranged on the top of the U-shaped steel arch frame 2, and the U-shaped steel arch frame 1 is fixed by the locking foot anchor rod, the bottom base 7 and the advance steel pipe 3; the gap between the U-shaped steel arch frame 2 and the boundary of the over-excavation area is filled with the negative Poisson's ratio structural plate 1; the negative Poisson's ratio structural plate 1 is fixed to the edge of the U-shaped steel arch frame 2 by acrylic adhesive, the negative Poisson's ratio structural plate 1 is arranged in a layered stacking manner according to the volume of the over-excavation area, and the negative Poisson's ratio structural plates 1 are bonded and connected by acrylic adhesive.

[0024] The negative Poisson's ratio structural plate 1 includes a plurality of rigid circular node units 8, which are spheres with a radius of 1.5 cm. The spheres are connected by fiber lines 9 to transfer loads. The negative Poisson's ratio structural plate 1 includes five layers of rigid circular node units 8, and the five layers of rigid circular node units 8 adopt a "5-4-5-4-5" structural arrangement combination; the rigid circular node units 8 are made of PVC, POM, PET and other materials with high strength, good toughness and low cost. The materials are light, easy to produce and transport, and easy to install, and will not bring cumbersome operation procedures to on-site operations.

[0025] Therefore, the present invention introduces a structural plate with a negative Poisson's ratio effect. The structural plate has good impact resistance, fracture resistance and energy absorption. On the one hand, it can withstand the pressure of the surrounding rock above and act as a "buffer layer" between the steel arch frame and the surrounding rock, allowing the surrounding rock to have a certain range of displacement to avoid large stress concentration; on the other hand, it can absorb a part of the blasting stress waves generated by the blasting operations in the mining field and adjacent mining fields, and reduce the influence of the blasting disturbance on the stability and support effect of the steel support structure to a certain extent, and can effectively improve the support effect of the U-shaped steel arch frame 2 and the life of the rock support, thereby ensuring safe and efficient underground operations.

[0026] In addition, the constituent units of the negative Poisson's ratio structural plate 1 are rigid circular node units 8, and therefore cannot be coupled to each other through a wedge-shaped structure. In order to enable continuous transmission of loads between the negative Poisson's ratio structural plates 1, the rigid circular node units 8 are connected by fiber lines 9, and acrylic adhesive is selected to connect the negative Poisson's ratio structural plates 1. The rigid circular node units 8 can also fit well to the edge of the U-shaped steel arch 2, and can also better adapt to the boundary within the overpressure area. Moreover, according to underground blasting regulations, the volume of the over-excavation area is generally not too large. Therefore, the relatively narrow space also allows the negative Poisson's ratio structural plates 1 to be in closer contact with each other, so that the negative Poisson's ratio structural plates 1 filled in the gaps in the over-excavation area form a whole, which is beneficial to the continuous transmission of the load and gives full play to the negative Poisson's ratio effect.

[0027] This embodiment also provides a construction method for the advanced support combined with the negative Poisson's ratio structural plate filling, and the construction steps are as follows: S1. Use a driving trolley to construct the mining tunnel according to the cross-sectional dimensions required by the design. After a single advance, use a trackless scraper to exit the mine. When constructing the mining tunnel, use smooth blasting to make the excavation contour as smooth and flat as possible, reduce the workload of secondary contour processing in the later stage, and create good conditions for filling the negative Poisson's ratio structural plate 1.

[0028] S2. Clean the ground gravel and deal with the loose stones on the roof of the mining tunnel after the mining is completed, and perform secondary treatment on the under-excavated area of ​​the cross-section contour to create conditions for the subsequent erection of the U-shaped steel arch frame 2 to ensure the safety of the operation; S3. Assemble and weld the U-shaped steel arch frame 2 in advance, and use a multi-purpose underground space 3D scanner to scan the actual excavation boundary contour in the area that needs support in the mining tunnel. The volume of the gap between the U-shaped steel arch frame 2 and the actual excavation contour is scanned, and the number of negative Poisson's ratio structural plates 1 required to fill the gap is calculated according to the size of the negative Poisson's ratio structural plate 1; when scanning, the multi-purpose underground space 3D scanner turns on the power of the scanning head in the empty area, and through control, 360° laser scanning without blind spots can be achieved, and the actual excavation contour boundary can be accurately obtained.

[0029] S4. Fix the negative Poisson's ratio structural plate 1 to the over-excavation area corresponding to the outer edge of the U-shaped steel arch frame 2 by acrylic adhesive, and add the negative Poisson's ratio structural plate 1 in a layered stacking manner according to the volume of the void in the over-excavation area. The negative Poisson's ratio structural plates 1 are also bonded and connected by acrylic adhesive. Acrylic adhesive has a fast curing speed, can adapt to harsh and extreme environments, and has high shear strength, peel strength and impact resistance. It can not only achieve a firm bond between the negative Poisson's ratio structural plate 1 and the U-shaped steel arch frame 2, but also can tightly combine the adjacent negative Poisson's ratio structural plates 1, and form the negative Poisson's ratio structural plates filled in the void into a whole, so as to give full play to the negative Poisson's ratio effect.

[0030] S5. The U-shaped steel arch frame 2 to which the negative Poisson's ratio structural plate 1 has been fixed is erected in the corresponding over-excavation area, so that the negative Poisson's ratio structural plate 1 fills the gap in the over-excavation area; specifically, a U-shaped steel arch frame 2 is erected every 1-1.2 m, and the U-shaped steel arch frames 2 are connected by steel plates made of 14# channel steel, and the longitudinal spacing of the connecting steel plates is 0.5-0.6 m; the leg sockets of the U-shaped steel arch frame 2 are dug down 100-200 mm to the solid bottom, and a base pad 6 is set at the bottom of the leg of the support. On the one hand, the bottom of the U-shaped steel arch frame 2 is erected more firmly, and on the other hand, the base excavated according to the size of the leg of the support forms a wedge-shaped structure coupling with the leg of the support, which also plays a fixing role; the locking foot anchor rod is installed at the distance of 1-1.2 m between the leg of the support and the bottom plate to further fix the U-shaped steel arch frame 2; finally, the left and right sides of the U-shaped steel arch frame 2 are connected and fixed again on the bottom plate with steel bars of 14# channel steel to complete the installation of the U-shaped steel arch frame 2.

[0031] S6. Finally, with the erected U-shaped steel arch frame 2 as the fulcrum, an advance steel pipe 3 is driven diagonally forward along the roof of the mining tunnel, and the advance support is completed in combination with the U-shaped steel arch frame 2. Specifically, after the U-shaped steel arch frame 2 is installed, the advance steel pipe 3 is installed on the top of the U-shaped steel arch frame 2. The advance steel pipe 3 is a φ32mm thin-walled steel pipe, 2m long, and installed at an elevation angle of 5°. The spacing between the advance steel pipes 3 is 200mm, and finally the advance support filled with the negative Poisson's ratio structural plate 1 is formed.

[0032] The present invention combines the construction method of advanced support with negative Poisson's ratio structural plate filling. By fully utilizing the mechanical properties of the negative Poisson's ratio structural plate, the stability of the filling body can be improved, the service life of the support facilities can be extended, the support cost can be saved, and the safety of underground operations can be guaranteed. In addition, the use of negative Poisson's ratio materials as new materials in mines conforms to the development trend of innovative mine construction. The characteristics of low material cost, light weight, and easy processing are in line with the development strategy of reducing costs and increasing efficiency in mines, and can be promoted for use in mines.

[0033] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0034] In the description of the present application, it should be understood that the terms "upper", "lower", etc. 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 application and simplifying the description, rather than indicating or implying that the device or element referred to 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 application.

[0035] 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 this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

Claims

1. An advanced support combined with negative Poisson's ratio structural plate filling, characterized in that: It comprises a negative Poisson's ratio structural plate (1), a U-shaped steel arch frame (2), an advanced steel pipe (3) and a locking anchor rod; The U-shaped steel arch frame (2) is erected in the over-excavation area, the U-shaped steel arch frame (2) is connected to the locking anchor rod and the bottom base (7), and the top of the U-shaped steel arch frame (2) is provided with an advanced steel pipe (3); The gap between the U-shaped steel arch frame (2) and the boundary of the over-excavation area is filled with a negative Poisson's ratio structural plate (1); the negative Poisson's ratio structural plate (1) is fixed to the edge of the U-shaped steel arch frame (2) by an acrylic adhesive, the negative Poisson's ratio structural plates (1) are arranged in a layered stacking manner according to the volume of the over-excavation area, and the negative Poisson's ratio structural plates (1) are bonded and connected by using an acrylic adhesive.

2. The advanced support combined with negative Poisson's ratio structural plate filling according to claim 1 is characterized in that: The negative Poisson's ratio structural plate (1) comprises a plurality of rigid circular node units (8), wherein the rigid circular node units (8) are connected via fiber lines (9).

3. The advanced support combined with negative Poisson's ratio structural plate filling according to claim 2 is characterized in that: The rigid circular node units (8) are spheres with a radius of 1.5 cm, the spheres are connected by fiber lines (9), and the negative Poisson's ratio structural plate (1) comprises five layers of rigid circular node units (8), the five layers of rigid circular node units (8) are arranged in a "5-4-5-4-5" structural combination.

4. The advanced support combined with negative Poisson's ratio structural plate filling according to claim 2 is characterized in that: The rigid circular node unit (8) is made of PVC material, POM material or PET material.

5. A construction method for advanced support combined with negative Poisson's ratio structural plate filling as claimed in any one of claims 1 to 4, characterized in that: The construction steps are as follows: S1. Use a tunneling trolley to construct the mining tunnel according to the cross-sectional dimensions required by the design. After a single advance, use a trackless scraper to carry out the mine; S2, cleaning the ground gravel and the loose stones on the roof of the mining tunnel after the mining is completed, and performing secondary processing on the under-excavated area of ​​the cross-section contour to create conditions for the subsequent erection of the U-shaped steel arch frame (2) to ensure the safety of the operation; S3, assembling and welding the U-shaped steel arch frame (2) in advance, scanning the actual excavation boundary contour with a multi-purpose underground space three-dimensional scanner in the area in the mining tunnel that needs to be supported, and obtaining the volume of the gap between the U-shaped steel arch frame (2) and the actual excavation contour, and calculating the number of negative Poisson's ratio structural plates (1) required to fill the gap according to the size of the negative Poisson's ratio structural plates (1); S4, fixing the negative Poisson's ratio structural plate (1) to the over-excavation area corresponding to the outer edge of the U-shaped steel arch frame (2) by using acrylic adhesive, and adding negative Poisson's ratio structural plates (1) in a layered stacking manner according to the volume of the gap in the over-excavation area, and the negative Poisson's ratio structural plates (1) are also bonded and connected by using acrylic adhesive; S5, erecting the U-shaped steel arch frame (2) to which the negative Poisson's ratio structural plate (1) has been fixed corresponding to the over-excavation area, so that the negative Poisson's ratio structural plate (1) fills the gap in the over-excavation area; S6. Finally, using the erected U-shaped steel arch frame (2) as a fulcrum, an advance steel pipe (3) is driven obliquely forward along the roof of the mining roadway, and the advance support is completed in combination with the U-shaped steel arch frame (2).

6. The construction method of the advanced support combined with negative Poisson's ratio structural plate filling according to claim 5 is characterized in that: In step S1, during the excavation of the mining tunnel, smooth blasting is used to make the excavation profile as smooth and flat as possible, thereby reducing the workload of secondary processing of the profile in the later stage and creating good conditions for filling the negative Poisson's ratio structural plate (1).

7. The construction method of advanced support combined with negative Poisson's ratio structural plate filling according to claim 5 is characterized in that: In step S3, the multi-purpose underground space three-dimensional scanner turns on the power of the scanning head in the empty area, and through control, 360° laser scanning without blind spots can be achieved, and the actual excavation contour boundary can be accurately obtained.

8. The construction method of advanced support combined with negative Poisson's ratio structural plate filling according to claim 5 is characterized in that: In step S4, the acrylic adhesive has a fast curing speed, can adapt to harsh and extreme environments, and has high shear strength, peel strength and impact resistance; it can not only achieve a firm bond between the negative Poisson's ratio structural plate (1) and the U-shaped steel arch frame (2), but also can tightly combine adjacent negative Poisson's ratio structural plates (1), forming the negative Poisson's ratio structural plates filled in the gap into a whole, and giving full play to the negative Poisson's ratio effect.

9. The construction method of advanced support combined with negative Poisson's ratio structural plate filling according to claim 5 is characterized in that: In step S5, a U-shaped steel arch frame (2) is erected every 1 to 1.2 m, and the U-shaped steel arch frames (2) are connected by steel plates made of 14# channel steel, and the longitudinal spacing of the connecting steel plates is 0.5 to 0.6 m; the leg sockets of the U-shaped steel arch frame are dug 100 to 200 mm downward to the solid bottom, which, on the one hand, makes the bottom of the U-shaped steel arch frame more firmly erected, and on the other hand, the base excavated according to the size of the leg is coupled with the leg to form a wedge-shaped structure, which also plays a fixing role; locking foot anchor rods are installed at a distance of 1 to 1.2 m from the leg to the bottom plate to further fix the U-shaped steel arch frame; finally, the left and right sides of the U-shaped steel arch frame are connected and fixed again on the bottom plate using steel bars made of 14# channel steel, thereby completing the installation of the U-shaped steel arch frame.

10. The construction method of advanced support combined with negative Poisson's ratio structural plate filling according to claim 5, characterized in that: In step S6, after the U-shaped steel arch frame (2) is installed, an advance steel pipe (3) is installed on the top of the U-shaped steel arch frame (2). The advance steel pipe (3) is a φ32 mm thin-walled steel pipe with a length of 2 m and is installed at an elevation angle of 5°. The spacing between the advance steel pipes (3) is 200 mm, and finally an advance support under negative Poisson's ratio structural plate filling is formed.

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