Advanced support combined with negative Poisson's ratio structural plate filling and its construction method

Abstract

The present invention discloses an advanced support combined with negative Poisson's ratio structural plate filling and a construction method thereof, relating to the technical field of mining tunnel support; the advanced support comprises a U-shaped steel arch frame, a negative Poisson's ratio structural plate, a locking anchor rod and an advanced steel pipe; the construction method comprises splicing and assembling the U-shaped steel arch frame on site according to design requirements, then using a multi-purpose underground space three-dimensional scanner to obtain the gap between the steel arch frame and the actual excavation boundary, calculating the number of negative Poisson's ratio structural plates required for filling, fixing the negative Poisson's ratio structural plates to the supporting edge of the U-shaped steel arch frame with acrylic adhesive, and also connecting adjacent structural plates with acrylic adhesive, and then installing the U-shaped steel arch frame in the required support area to complete the support; the present invention solves the support problems of the prior art such as short service life of the U-shaped steel arch frame, poor support effect, failure due to large deformation of the arch frame, and great safety hazards in on-site operations.

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] With the widespread use of backfill mining in underground mines, the recovery of pillars or residual ore trapped within backfill has become a common problem faced by many mines in the later stages. To recover such ore bodies, some mining and cutting projects have to be arranged within the backfill of adjacent, already filled stopes, which poses a significant safety hazard to tunnel excavation and support. For tunnels within such backfills, advanced support technologies such as combined support of advanced steel pipes and U-shaped steel arches, and advanced pipe shed support are generally used. These advanced support technologies require the use of U-shaped steel arches to provide support. However, over-excavation and under-excavation are inevitable during tunnel excavation, resulting in deviations between the actual excavation cross-sectional profile and the designed cross-sectional profile. This causes point support to form in the under-excavation area when the U-shaped steel arch is used, resulting in significant stress concentration. In the over-excavation area, however, no support is provided to the entity, failing to provide actual support for the tunnel. This low-quality support not only significantly shortens the service life of the U-shaped steel arches and increases support costs, but also poses a significant safety hazard to tunnel operations.

[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] To address the above technical issues, the present invention provides an advanced support system incorporating negative Poisson's ratio structural plate filling and its construction method. This system primarily addresses the over- and under-excavation phenomena found in actual excavation sections during tunneling projects. Conventional U-shaped steel arches, when used for support, can cause local stress concentration zones in under-excavated areas of the tunnel, as well as ineffective support of the surrounding rock mass in over-excavated areas. This can lead to short U-shaped steel arch life, poor support effectiveness, large deformation failure, and significant safety hazards during on-site operations. This construction method builds on the advanced support technology of combined advanced steel pipe and U-shaped steel arch support, incorporating negative Poisson's ratio structural plate filling to improve support effectiveness.

[0005] The present invention provides an advanced support combined with negative Poisson's ratio structural plate filling, which adopts the following technical solutions:

[0006] 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 anchor rod;

[0007] 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;

[0008] 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, and 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 with acrylic adhesive.

[0009] 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.

[0010] 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 adopt a "5-4-5-4-5" structural arrangement combination.

[0011] Preferably, the rigid circular node unit is made of PVC material, POM material or PET material.

[0012] 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:

[0013] S1. Use a tunneling trolley to construct the mining tunnel according to the design cross-sectional dimensions. After a single advance, use a trackless scraper to remove the mine.

[0014] S2. Clean the ground gravel and deal with loose rocks on the roof of the mining roadway after mining is completed. Perform secondary treatment on the under-excavated area of ​​the cross-section contour to create conditions for the subsequent erection of U-shaped steel arches and ensure operational safety.

[0015] S3. Assemble and weld the U-shaped steel arch frame in advance. Use a multi-purpose underground space 3D scanner to scan the actual excavation boundary contour in the area requiring support in the mining tunnel. The scan determines the volume of the gap between the U-shaped steel arch frame and the actual excavation contour. Calculate the number of negative Poisson's ratio structural plates required to fill the gap based on the size of the negative Poisson's ratio structural plates.

[0016] S4. Fix the negative Poisson's ratio structural panels to the over-excavation area corresponding to the outer edge of the U-shaped steel arch frame using acrylic adhesive, and add negative Poisson's ratio structural panels in a layered stacking manner according to the volume of the void in the over-excavation area. The negative Poisson's ratio structural panels are also bonded and connected using acrylic adhesive;

[0017] 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;

[0018] S6. Finally, using the erected U-shaped steel arch as a fulcrum, drive advance steel pipes diagonally forward along the roof of the mining roadway, and combine with the U-shaped steel arch to complete the advance support.

[0019] Preferably, in step S1, when constructing the mining tunnel, smooth blasting is used to make the excavation profile as smooth and flat as possible, 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.

[0020] 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.

[0021] 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, form the negative Poisson's ratio structural plates filled in the gap into a whole, and give full play to the negative Poisson's ratio effect.

[0022] Preferably, in step S5, a U-shaped steel arch frame is erected every 1 to 1.2 m, and the U-shaped steel arch frames are connected by steel plates made of 14# channel steel, with a longitudinal spacing of 0.5 to 0.6 m; the leg sockets of the U-shaped steel arch frame are dug down 100 to 200 mm 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 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 to 1.2 m from the support legs to further fix the U-shaped steel arch frame; finally, 14# channel steel bars are used on the bottom plate to reconnect and fix the left and right sides of the U-shaped steel arch frame to complete the installation of the U-shaped steel arch frame.

[0023] 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 the negative Poisson's ratio structural plate filling.

[0024] Beneficial effects of the present invention:

[0025] The present invention introduces a negative Poisson's ratio structural plate, fully utilizing the mechanical properties of negative Poisson's ratio structures. When subjected to axial tension (or compression), negative Poisson's ratio materials expand (or contract) in the vertical direction. This negative Poisson's ratio effect imparts excellent impact resistance, fracture resistance, and energy absorption and vibration isolation properties. The negative Poisson's ratio structural plate is placed within the over-excavation area, serving as a buffer layer between the upper backfill and the U-shaped steel arch. As the backfill gradually deforms due to creep, the negative Poisson's ratio structural plate deforms under the pressure exerted by the backfill, exerting the negative Poisson's ratio effect and allowing the upper backfill to deform to a certain extent, thereby avoiding the stress concentration associated with traditional rigid U-shaped steel arch supports. Furthermore, when blasting operations occur in the adjacent stope, the negative Poisson's ratio structural plate can absorb a portion of the blasting stress wave, preventing the backfill and U-shaped steel arch from being directly subjected to the disturbance of the blasting stress wave and causing instability.

[0026] Compared with other shapes, the rigid circular spheres that constitute 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 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 work processes to on-site operations.

[0027] 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 goal of reducing costs and increasing efficiency in mines, and can be promoted for use in mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] For ease of explanation, the present invention is described in detail with reference to the following specific implementations and accompanying drawings.

[0029] Figure 1 This is the main view of the advance support combined with the negative Poisson's ratio structural plate infill;

[0030] Figure 2 for Figure 1 Lateral section at middle II-II;

[0031] Figure 3 Schematic diagram of negative Poisson's ratio structural plate and connection between structural plates;

[0032] Figure 4 Schematic diagram of the connection between the negative Poisson's ratio structural plate and the U-shaped steel arch frame.

[0033] In the picture:

[0034] 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 element; 9-Fiber line. DETAILED DESCRIPTION

[0035] The following are specific embodiments of the present invention, which, in conjunction with the accompanying drawings, further describe the technical solutions of the present invention. However, 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 facilitate a comprehensive understanding of the embodiments of the present invention. Therefore, it should be clear to those skilled in the art that various changes and modifications may 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, descriptions of known functions and structures have been omitted.

[0036] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other.

[0037] like Figure 1-Figure 4 As shown, an advance support combined with negative Poisson's ratio structural plate filling provided by 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.

[0038] The negative Poisson's ratio structural plate 1 includes a plurality of rigid circular node units 8. The rigid circular node units 8 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. 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 processes to on-site operations.

[0039] 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, act as a "buffer layer" between the steel arch frame and the surrounding rock, and allow the surrounding rock to have a certain range of displacement to avoid large stress concentration; on the other hand, it can absorb part of the blasting stress waves generated by the blasting operations in the mining area and adjacent mining areas, and reduce the impact of the blasting disturbance on the stability and support effect of the steel support structure to a certain extent. It can effectively improve the support effect of the U-shaped steel arch frame 2 and the rock support life, and ensure safe and efficient underground operations.

[0040] 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 with 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 conducive to the continuous transmission of loads and fully exerts the negative Poisson's ratio effect.

[0041] 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:

[0042] S1. Use a tunneling trolley to construct the mining tunnel according to the cross-sectional dimensions required by the design. After a single advance, a trackless scraper is used to transport the mine. When constructing the mining tunnel, smooth blasting is used to make the excavation profile as smooth and flat as possible, 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.

[0043] S2. Clean the ground gravel and the loose rocks on the roof of the mining roadway after the mining is completed, and perform 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 operation safety;

[0044] 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 scan obtains the volume of the gap between the U-shaped steel arch frame 2 and the actual excavation contour, and calculates the number of negative Poisson's ratio structural plates 1 required to fill the gap based on the size of the negative Poisson's ratio structural plates 1; during scanning, the multi-purpose underground space 3D scanner turns on the power of the scanning head in the empty area, and through control, it can achieve 360° laser scanning without blind spots, and can accurately obtain the actual excavation contour boundary.

[0045] 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 using acrylic adhesive, and add negative Poisson's ratio structural plates 1 in a layered stacking manner according to the volume of the gap in the over-excavation area. The negative Poisson's ratio structural plates 1 are also bonded and connected by using 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 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.

[0046] S5. The U-shaped steel arch frame 2 with the negative Poisson's ratio structural plate 1 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 1-1.2m, and the U-shaped steel arch frames 2 are connected by steel plates made of 14# channel steel, with a longitudinal spacing of 0.5-0.6m; the leg sockets of the U-shaped steel arch frame 2 are dug down 100-200mm to the solid bottom, and a base pad 6 is set at the bottom of the leg. On the one hand, it makes the bottom of the U-shaped steel arch frame 2 more firmly erected, and on the other hand, the base excavated according to the size of the leg forms a wedge-shaped structure coupling with the leg, which also plays a fixing role; locking anchor rods are installed at the distance of 1-1.2m between the leg 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 reconnected and fixed on the bottom plate using 14# channel steel bars to complete the installation of the U-shaped steel arch frame 2.

[0047] S6. Finally, using the erected U-shaped steel arch frame 2 as a fulcrum, drive an advance steel pipe 3 diagonally forward along the roof of the mining roadway, and complete the advance support in combination with the U-shaped steel arch frame 2. Specifically, after the U-shaped steel arch frame 2 is installed, install the advance steel pipe 3 on the top of the U-shaped steel arch frame 2. The advance steel pipe 3 is a φ32mm thin-walled steel pipe with a length of 2m. It is installed at an elevation angle of 5°. The spacing between the advance steel pipes 3 is 200mm, and finally form an advance support filled with the negative Poisson's ratio structural plate 1.

[0048] 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, it 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. 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.

[0049] 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, they indicate the presence of features, steps, tasks, devices, components and / or combinations thereof.

[0050] In the description of this application, it should be understood that the terms "upper" and "lower" 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 this 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 this application.

[0051] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

Claims

1. An advanced support combined with negative Poisson's ratio structural plate filling, characterized in that: It includes 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 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 an acrylic adhesive; 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 by fiber lines (9); The rigid circular node units (8) are spheres with a radius of 1.5 cm, and the spheres are connected by fiber lines (9). 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.

2. The advanced support combined with negative Poisson's ratio structural plate filling according to claim 1 is characterized in that: The rigid circular node unit (8) is made of PVC material, POM material or PET material.

3. A construction method for advanced support combined with negative Poisson's ratio structural plate filling according to any one of claims 1 to 2, characterized in that: The construction steps are as follows: S1. Use a tunneling trolley to construct the mining tunnel according to the design cross-sectional dimensions. After a single advance, use a trackless scraper to remove the mine. 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 processing on the under-excavated area of ​​the cross-section contour to create conditions for the subsequent erection of the U-shaped steel arch (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 three-dimensional scanner to scan the actual excavation boundary contour in the area where support is required in the mining tunnel. The volume of the gap between the U-shaped steel arch frame (2) and the actual excavation contour is obtained by scanning, and the number of negative Poisson's ratio structural plates (1) required to fill the gap is calculated based on 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) on which the negative Poisson's ratio structural plate (1) is 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 top plate of the mining roadway, and the advance support is completed in combination with the U-shaped steel arch frame (2).

4. The construction method of the advanced support combined with negative Poisson's ratio structural plate filling according to claim 3 is characterized in that: In step S1, when the mining tunnel is excavated, 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).

5. The construction method of the advanced support combined with negative Poisson's ratio structural plate filling according to claim 3 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, realizes 360° laser scanning without blind spots through control, and accurately obtains the actual excavation contour boundary.

6. The construction method of the advanced support combined with negative Poisson's ratio structural plate filling according to claim 3 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.

7. The construction method of advanced support combined with negative Poisson's ratio structural plate filling according to claim 3 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, with a longitudinal spacing of 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 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 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.

8. The construction method of advanced support combined with negative Poisson's ratio structural plate filling according to claim 3 is 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 φ32mm thin-walled steel pipe with a length of 2m and is installed at an elevation angle of 5°. The spacing between the advance steel pipes (3) is 200mm, and finally an advance support under the negative Poisson's ratio structural plate filling is formed.

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