Negative Poisson's ratio geotechnical metamaterial structure of bionic muscle fiber and preparation method of negative Poisson's ratio geotechnical metamaterial structure

Abstract

The invention discloses a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure and a preparation method thereof.The bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure structurally comprises a plurality of negative Poisson's ratio units which are transversely connected at intervals and longitudinally connected adjacently, and each negative Poisson's ratio unit comprises two first rods which transversely extend and are longitudinally arranged at intervals, the unit surface layers are connected to the two transverse ends of the two first rods; each unit surface layer is of a telescopic wrinkle structure; second rods are connected to the middles of the transversely adjacent negative Poisson's ratio units, and the longitudinally adjacent second rods and the unit surface layers in the negative Poisson's ratio units form self-similar negative Poisson's ratio units. The material has higher energy absorption capacity and more uniform stress distribution, and the overall toughness and impact resistance of the material are enhanced; according to the preparation method, the local engineering metamaterial has good bending strength and compressive strength, one-time forming and integrity of the material are ensured, and the production process is simplified.

Description

Technical Field

[0001] The present invention relates to the field of civil engineering materials, and particularly to a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure and a preparation method thereof. Background Art

[0002] In civil engineering and geological disaster prevention, traditional vibration damping and earthquake-resistant materials usually adopt single metals or composite materials. These conventional materials have a positive Poisson's ratio effect, that is, when the material is stretched or compressed in one direction, its lateral direction (perpendicular to the stress direction) will contract or expand correspondingly. However, in the face of high-intensity seismic waves, blasting shocks or other complex stress conditions, positive Poisson's ratio materials may not provide sufficient protection.

[0003] Materials with negative Poisson's ratio effect show lateral expansion when stretched and lateral contraction when compressed, and can exhibit unique mechanical properties different from traditional materials. With the high applicability to the working conditions environment, the performance requirements for materials with negative Poisson's ratio effect are also relatively high. The traditional concave hexagonal honeycomb metamaterial is a typical mechanical metamaterial. Although it has good negative Poisson's ratio performance, its energy absorption, stress distribution and crack propagation resistance ability are limited when subjected to large impact forces, and it cannot meet the use environment of high-intensity seismic waves, blasting shocks or other complex stresses. Therefore, it is urgent to develop a new type of vibration damping and earthquake-resistant negative Poisson's ratio geotechnical metamaterial. Summary of the Invention

[0004] The purpose of the present invention is to provide a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure, which not only has higher energy absorption capacity and more uniform stress distribution, enhances the overall toughness and impact resistance of the material, and can be applicable to the use environment of high-intensity seismic waves, blasting shocks or other complex stresses.

[0005] To achieve the above purpose, a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure of the present invention includes:

[0006] A plurality of negative Poisson's ratio units, which are connected at intervals horizontally and adjacent longitudinally;

[0007] Each negative Poisson's ratio unit includes:

[0008] Two first rods extending horizontally and arranged at intervals longitudinally, and a unit surface layer connected to the horizontal ends of the two first rods; each unit surface layer is a foldable structure capable of stretching;

[0009] Wherein, a second rod is connected to the middle parts of adjacent negative Poisson's ratio units horizontally, and the second rod adjacent longitudinally and the unit surface layer in the negative Poisson's ratio unit form a self-similar negative Poisson's ratio unit.

[0010] In some examples of the present invention, the interior of the negative Poisson's ratio unit and the self-similar negative Poisson's ratio unit are both filled with fillers.

[0011] In some examples of the present invention, the filler is lightweight foam soil.

[0012] In some examples of the present invention, the surface layer of the unit is arranged in an arc shape;

[0013] The middle parts of the surface layers of a pair of units approach each other to form a funnel structure with a wide longitudinal end and a narrow middle.

[0014] The present invention also aims to provide a preparation method for a bionic muscle fiber negative Poisson's ratio geosynthetic metamaterial structure, which can endow the native geosynthetic metamaterial with good bending strength and compressive strength, and adopts 3D printing technology combined with selective laser sintering to ensure the one-time forming and integrity of the material, and simplifies the production process;

[0015] A preparation method for a bionic muscle fiber negative Poisson's ratio geosynthetic metamaterial structure specifically includes the following steps:

[0016] S1. First, powderize and grind high-performance polyurethane prepolymer and polyether ether ketone as the basic polymer matrix materials, grind the particulate reinforcing material and the fiber reinforcing material as the reinforcing materials respectively, and then mix the powders obtained by grinding and perform high-speed stirring;

[0017] S2: Prepare lightweight foam soil by the foaming method;

[0018] S3: Use selective laser sintering 3D printing technology to prepare and form in one step, and simultaneously fill lightweight foam soil, binder, and functional additives during the printing process;

[0019] S4. After the solid in step S3 cools and solidifies, spray a protective coating on the surface by the high-pressure airless spraying method to obtain a bionic muscle fiber negative Poisson's ratio geosynthetic metamaterial structure.

[0020] In some examples of the present invention, the particulate reinforcing material in step S1 includes one or more of carbon nanotubes, graphene, and nano-aluminum oxide;

[0021] The fiber reinforcing material is one or more of aramid fiber, UHMWPE fiber, and carbon fiber;

[0022] In step S1, by weight percentage, the polyurethane prepolymer is 50%, the polyether ether ketone is 30%, the particulate reinforcing material is 13%, and the fiber reinforcing material is 7%.

[0023] In some examples of the present invention, in step S3, the binder is one or more of flexible epoxy resin, polyurethane, silicone rubber, and acrylate;

[0024] The functional additive is one or more of nano-titanium dioxide, magnetic nanoparticles, and zinc oxide nanoparticles.

[0025] In some examples of the present invention, in step S4, the spraying thickness is between 0.5 - 1 mm;

[0026] The formulation ratio of the protective coating is 45% polyurethane acrylate resin, 30% silicone-modified epoxy resin, 8% dicyandiamide curing agent, 7% isophorone diisocyanate curing agent, 5% aluminum powder, 2% titanium dioxide micropowder, 2% boron nitride micropowder, 1% leveling agent, 1% defoaming agent, and 1% dispersant.

[0027] In some examples of the present invention, in step S1, the grinding time of the base polymer matrix material and the reinforcing material is 1 h - 1.5 h;

[0028] After grinding is completed, add it to a high-speed mixer and stir at a speed of 2000 revolutions per minute for 30 minutes.

[0029] Compared with the prior art, the negative Poisson's ratio geotechnical metamaterial structure of a bionic muscle fiber is formed by multiple funnel-shaped negative Poisson's ratio units connected to each other longitudinally and spaced transversely to form self-similar negative Poisson's ratio units. This alternating arrangement is similar to the three-dimensional structure of muscle fibers. It can not only enhance the overall stability and strength of the material, but also ensure uniform stress distribution and efficient energy absorption under external forces. When subjected to external forces, it can effectively disperse stress, prevent local stress concentration, thereby improving the overall impact resistance performance, enhancing the crack propagation resistance ability of the material, and further enhancing the crack propagation resistance ability of the material, further improving its durability and reliability; in addition, the surface layer of the unit adopts a bionic wrinkled structure, which can undergo micro-stretching when stressed, thereby generating a negative Poisson's ratio effect.

[0030] Since the inside of the negative Poisson's ratio unit and the self-similar negative Poisson's ratio unit are both filled with fillers, the fillers collide with each other when subjected to impact, thereby effectively absorbing and dispersing energy, further improving the energy absorption ability and impact resistance performance of the material. And when the filler is lightweight foam soil, while ensuring the energy absorption effect, the weight of the overall structure is reduced, which is convenient for transportation and construction.

[0031] The preparation method of the negative Poisson's ratio geotechnical metamaterial structure of a bionic muscle fiber of the present invention, on the one hand, determines the matrix material and optimizes the proportion of each component in the material to ensure that the geotechnical metamaterial has good flexural strength and compressive strength. On the other hand, it adopts 3D printing technology combined with selective laser sintering to ensure the one-time forming and integrity of the material, simplifies the production process, and adds functional additives, which not only improves the comprehensive performance of the material, but also expands its application range, making it suitable for more complex environments. Description of the Drawings

[0032] Figure 1 is a schematic structural diagram of a negative Poisson's ratio geosynthetic metamaterial structure of a bionic muscle fiber in the present invention;

[0033] Figure 2 is Figure 1 an enlarged view of the area of the negative Poisson's ratio unit in;

[0034] Figure 3 is a graph showing the influence of the addition amount of the particulate reinforcing material on the flexural strength and compressive strength of the native geosynthetic metamaterial in the present invention;

[0035] Figure 4 is a graph showing the influence of the addition amount of the fiber reinforcing material on the flexural strength and compressive strength of the native geosynthetic metamaterial in the present invention;

[0036] Figure 5 is a graph showing the influence of the TUP ratio in the matrix material on the flexural strength and compressive strength of the native geosynthetic metamaterial in the present invention;

[0037] In the figure: 10, negative Poisson's ratio unit; 11, first rod; 12, unit surface layer; 13, filler.

[0038] 20, self-similar negative Poisson's ratio unit; 21, second rod. Detailed Embodiments

[0039] In order to make the objectives, technical solutions, and advantages of the technical solutions of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of specific embodiments of the present invention. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are some embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] Unless otherwise defined, the technical terms or scientific terms used herein shall have the ordinary meanings as understood by those of ordinary skill in the art to which this invention pertains. The terms "first", "second" and similar terms used in the specification and claims of this patent application for invention do not denote any order, quantity or importance, but are only used to distinguish different components. Similarly, terms such as "a" or "an" do not necessarily denote a quantity limitation. Terms such as "comprising" or "including" mean that the elements or items appearing before this word cover the elements or items listed after this word and their equivalents, without excluding other elements or items. Terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Terms such as "upper", "lower", "left" and "right" are only used to indicate relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0041] As Figure 1 , Figure 2 shown, a negative Poisson's ratio geotechnical metamaterial structure of a bionic muscle fiber includes:

[0042] A plurality of negative Poisson's ratio units 10, which are connected at intervals transversely and adjacent longitudinally;

[0043] Each negative Poisson's ratio unit 10 includes:

[0044] Two first rods 11 extending transversely and arranged at intervals longitudinally, and a unit surface layer 12 connected to the transverse two ends of the two first rods 11; each unit surface layer 12 is a foldable structure capable of expansion and contraction;

[0045] Wherein, a second rod 21 is connected to the middle parts of adjacent negative Poisson's ratio units 10 transversely, and the second rod 21 adjacent longitudinally and the unit surface layer 12 in the negative Poisson's ratio unit 10 form a self-similar negative Poisson's ratio unit 20;

[0046] Specifically, a plurality of negative Poisson's ratio units 10 are spaced at intervals transversely and connected by the second rods 21, and are connected to each other longitudinally, and the second rods 21 connected to the middle parts of the negative Poisson's ratio units 10 and the unit surface layer 12 in the negative Poisson's ratio units 10 form self-similar negative Poisson's ratio units 20, so that a plurality of negative Poisson's ratio units 10 are alternately arranged and stacked to form a three-dimensional structure similar to muscle fibers. This alternating arrangement can not only enhance the overall stability and strength of the material, but also ensure uniform stress distribution and efficient energy absorption under external forces. When an external force acts, the mutual support between adjacent negative Poisson's ratio units 10 and self-similar negative Poisson's ratio units 20 can effectively disperse the stress, prevent local stress concentration, thereby improving the overall impact resistance performance, and this structure can enhance the crack propagation resistance ability of the material, further improving its durability and reliability;

[0047] The surface layer 12 of the unit adopts a bionic fold structure, which can undergo a small amount of expansion and contraction when stressed, thereby generating a negative Poisson's ratio effect;

[0048] This bionic muscle fiber-based geosynthetic metamaterial structure with negative Poisson's ratio not only has excellent mechanical properties and energy absorption characteristics, but also provides a more uniform stress distribution and higher crack propagation resistance; the unique microstructure and material combination enable the metamaterial to exhibit remarkable vibration damping and seismic resistance effects when facing high-intensity seismic waves, blasting shocks or other complex stress conditions. Especially in civil engineering, geological disaster prevention and infrastructure construction projects, it can effectively reduce the impact of disasters such as earthquakes and explosions on buildings and infrastructure, and ensure the safety of personnel and property.

[0049] In some examples of the present invention, the interior of the negative Poisson's ratio unit 10 and the self-similar negative Poisson's ratio unit 20 both have a filler 13;

[0050] Preferably, the filler 13 is lightweight foam soil;

[0051] Specifically, the negative Poisson's ratio unit 10 and the self-similar negative Poisson's ratio unit 20 are both filled with lightweight foam soil or other small particles. These fillers 13 collide with each other when subjected to impact, thereby effectively absorbing and dispersing energy, and further improving the energy absorption capacity and impact resistance of this metamaterial; especially lightweight foam soil, its porous structure can not only provide excellent energy absorption effect, but also maintain a low density, reducing the weight of the overall structure, making the metamaterial not only have excellent mechanical properties, but also have the advantage of lightweight, which is convenient for transportation and construction;

[0052] In addition, to ensure the stability of the filling material in the voids and enhance the consistency of the overall structure, an appropriate amount of binder is used inside the negative Poisson's ratio unit 10 and the self-similar negative Poisson's ratio unit 20, which can fix the filling material. At the same time, some functional additives are added to endow the material with additional functional characteristics. The additives can not only improve the comprehensive performance of the material, but also expand its application range, making it suitable for more complex environments.

[0053] In some examples of the present invention, the unit surface layer 12 is arranged in an arc shape;

[0054] The middle parts of a pair of unit surface layers 12 approach each other to form a funnel structure with a wide longitudinal end and a narrow middle;

[0055] Specifically, the laterally adjacent unit surface layers 12 can form a funnel structure with a wide longitudinal top and a narrow middle. Similarly, the self-similar negative Poisson's ratio unit 20 is also a funnel structure in terms of structure. Preferably, in terms of size, the self-similar negative Poisson's ratio unit 20 is the same as the negative Poisson's ratio unit 10;

[0056] The funnel structure enables the metamaterial to better form a three-dimensional structure similar to muscle fibers after arrangement, and they are alternately arranged and stacked to form a three-dimensional network structure, thereby better enhancing the overall stability and strength of the material.

[0057] A preparation method of a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure specifically includes the following steps:

[0058] S1. First, put the high-performance polyurethane prepolymer and polyether ether ketone as the basic polymer matrix materials into a ball mill for powder grinding. The particulate reinforcing material and fiber reinforcing material are ground separately as reinforcing materials, and then the powder of each component obtained by grinding is mixed and subjected to high-speed stirring;

[0059] Specifically, put the basic polymer matrix materials into a ball mill for powder grinding, and the reinforcing materials are also ground. The grinding time is 1h - 1.5h; after the grinding is completed, then add the high-performance polyurethane prepolymer, polyether ether ketone, particulate reinforcing material, and fiber reinforcing material powders into a high-speed mixer and stir at a speed of 2000 revolutions per minute for 30 minutes;

[0060] S2: Prepare lightweight foamed soil by the foaming method;

[0061] Specifically, the lightweight foamed soil is used as the internal filling material of the corresponding unit and is prepared by the foaming method. Its density and porosity are controlled by adjusting the proportion of the foaming agent to achieve an ideal energy absorption effect. After preparation, it is sieved to meet the standard of internal filling particles;

[0062] S3: Use the selective laser sintering 3D printing technology to prepare and form it at one time, and synchronously fill lightweight foamed soil, binder, and functional additives during the printing process;

[0063] S4. After the solid in step S3 is cooled and solidified, spray a protective coating on the surface by the high-pressure airless spraying method to obtain a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure;

[0064] In some examples of the present invention, the particulate reinforcing material in step S1 includes one or more of carbon nanotubes, graphene, and nano-aluminum oxide;

[0065] The fiber reinforcing material is one or more of aramid fiber, UHMWPE fiber, and carbon fiber;

[0066] In step S1, by weight percentage, the polyurethane prepolymer is 50%, the polyether ether ketone is 30%, the particulate reinforcing material is 13%, and the fiber reinforcing material is 7%;

[0067] Example

[0068] Such as Figure 3As shown, when the addition amount of the particulate reinforcing material gradually increases, the influence curve graphs of its flexural strength and compressive strength on the domestic engineering supermaterial are shown. At this time, the compressive strength increases with the increase of the particulate reinforcing material, showing an overall trend of fluctuating upward, with a rapid increase in the early stage. After the addition amount reaches 11%, there is a downward trend; while the flexural strength decreases with the increase of the particulate reinforcing material.

[0069] As Figure 4 shown, when the addition amount of the fiber reinforcing material gradually increases, the influence curve graphs of its flexural strength and compressive strength on the domestic engineering supermaterial are shown. The effects of the fiber reinforcing material and the particulate reinforcing material are opposite, but the overall trends are similar. Therefore, to balance the effects of the fiber reinforcing material and the particulate reinforcing material and pursue higher material properties, 13% fiber reinforcing material and 7% particulate reinforcing material are selected for use;

[0070] As Figure 5 shown, the influence curve graphs of the high-performance polyurethane prepolymer (TPU) and polyetheretherketone (PEEK) as the base polymer matrix material ratio on the flexural strength and compressive strength of the domestic engineering supermaterial are shown. At this time, when the content of the high-performance polyurethane prepolymer (TPU) gradually increases, the relative compressive strength gradually increases, and the relative flexural strength gradually decreases, while the effect of polyetheretherketone (PEEK) is the opposite; when the content ratio is approximately 0.6, the trends of both slow down relatively. Therefore, for better material properties, 50% high-performance thermoplastic polyurethane and 30% polyetheretherketone are selected for use.

[0071] In some examples of the present invention, in the step S3, the binder is one or more of flexible epoxy resin, polyurethane, silicone rubber, and acrylate;

[0072] The functional additive is one or more of nano-titanium dioxide, magnetic nanoparticles, and zinc oxide nanoparticles.

[0073] In some examples of the present invention, in the step S4, the spraying thickness is between 0.5 - 1 mm;

[0074] The formulation ratio of the protective coating is 45% polyurethane acrylate resin, 30% organosilicon-modified epoxy resin, 8% dicyandiamide curing agent, 7% isophorone diisocyanate curing agent, 5% aluminum powder, 2% titanium dioxide micropowder, 2% boron nitride micropowder, 1% leveling agent, 1% defoaming agent, and 1% dispersant;

[0075] In addition, the high-pressure airless spraying method in the step S5 specifically includes the following steps:

[0076] 1. Preparation work: Ensure that the surface to be sprayed is clean, free of oil, dust, and other impurities;

[0077] Specifically, the surface can be wiped with a solvent or rinsed with high-pressure water, and sanded with sandpaper if necessary; prepare the appropriate ratio according to the coating instructions. First, mix epoxy resin and polyurethane evenly according to the formula ratio, then add amine curing agent and isocyanate curing agent respectively, stir evenly, and finally add other additives;

[0078] 2. Equipment preparation: Check the spraying equipment, which is mainly a high-pressure airless spraying machine, to ensure that the spraying equipment is in good condition, the nozzle is clean and unblocked, and the high-pressure pipeline has no leakage; connect the power supply and the compressed air source; connect the spraying machine to the power supply and ensure that the compressed air source is working properly and providing sufficient air pressure; according to the coating characteristics and spraying requirements, adjust the spraying pressure of the spraying machine to 3000 psi (about 207 bar), the flow rate to 0.4 gpm (about 1.5 L / min), the nozzle size to 0.015 inches (about 0.38 mm), and the spray pattern to 8 to 10 inches (about 20 to 25 cm);

[0079] 3. Formal spraying: Keep the nozzle at a 90-degree angle to the spraying surface to ensure uniform coating coverage; usually, the distance between the nozzle and the surface is maintained between 20 - 30 cm, adjusted specifically according to the spraying equipment and coating characteristics; maintain a uniform speed to avoid being too fast or too slow to prevent the coating from being too thin or too thick; each time when spraying, ensure that there is a certain overlap between adjacent spray bands (usually 50%) to ensure the uniformity of the coating;

[0080] 4. Multi-layer spraying: Spray multiple layers, and ensure that each layer is dry before spraying the next layer. Wait for an appropriate time according to the coating characteristics and environmental conditions (usually from a few minutes to half an hour); repeat the above steps as needed until the required coating thickness is achieved.

[0081] 5. Drying and curing: After spraying, let the coating dry and cure under natural conditions. Depending on the coating characteristics and environmental conditions, it usually takes several hours to one day; if it is necessary to accelerate the curing process, the sprayed workpiece can be placed in an oven and heated and cured at an appropriate temperature, and the specific temperature and time are adjusted according to the coating instructions.

[0082] 6. Inspection and repair: Check whether the coating is uniform and free of defects;

[0083] If there are areas with missed spraying or uneven coating, re-spraying or repair is required; evaluate the performance indicators such as the adhesion and hardness of the coating to ensure compliance with the requirements.

[0084] In the foregoing, a demonstration implementation manner of a negative Poisson's ratio geotechnical metamaterial structure of bionic muscle fibers proposed by the present invention has been described in detail with reference to preferred embodiments. However, those skilled in the art can understand that, without departing from the concept of the present invention, various modifications and variations can be made to the above specific embodiments, and various combinations of the various technical features and structures proposed by the present invention can be made without exceeding the protection scope of the present invention. The protection scope of the present invention is determined by the appended claims.

Claims

1. A bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure, characterized in that: include: A plurality of negative Poisson's ratio units (10) are connected in a spaced manner in the transverse direction and adjacently in the longitudinal direction; Each negative Poisson's ratio unit (10) comprises: Two first rods (11) extending in the transverse direction and arranged at intervals in the longitudinal direction, and a unit surface layer (12) connected to both transverse ends of the two first rods (11); each unit surface layer (12) is a pleated structure capable of expansion and contraction; The middle parts of the laterally adjacent negative Poisson's ratio units (10) are connected with second rods (21), and the longitudinally adjacent second rods (21) and the unit surface layer (12) in the negative Poisson's ratio unit (10) form a self-similar negative Poisson's ratio unit (20).

2. The negative Poisson's ratio geotechnical metamaterial structure of bionic muscle fiber according to claim 1, characterized in that: The negative Poisson's ratio unit (10) and the self-similar negative Poisson's ratio unit (20) are both filled with fillers (13).

3. The negative Poisson's ratio geotechnical metamaterial structure of a bionic muscle fiber according to claim 2, characterized in that: The filler (13) is light foam soil.

4. The negative Poisson's ratio geotechnical metamaterial structure of bionic muscle fiber according to claim 3, characterized in that: The unit surface layer (12) is arranged in an arc shape; The middle parts of a pair of unit surface layers (12) are close to each other to form a funnel structure with wide ends and narrow middle.

5. A method for preparing a negative Poisson's ratio geotechnical metamaterial structure of bionic muscle fiber according to any one of claims 1 to 4, characterized in that: The specific steps include: S1, firstly, high-performance polyurethane prepolymer and polyetheretherketone as basic polymer matrix materials are powdered and ground, and particle reinforcement material and fiber reinforcement material as reinforcement materials are ground separately, and then the powders obtained by grinding are mixed and stirred at high speed; S2: Lightweight foam soil is prepared by foaming method; S3: Use selective laser sintering 3D printing technology to prepare and shape in one go, and simultaneously fill lightweight foam soil, binder, and functional additives during the printing process; S4, after the solid matter in step S3 is cooled and solidified, a protective coating is sprayed on the surface by a high-pressure airless spraying method to obtain a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure.

6. The method for preparing a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure according to claim 5, characterized in that: The particle reinforcement material in step S1 includes one or more of carbon nanotubes, graphene and nano-alumina; The fiber reinforcement material is one or more of aramid fiber, UHMWPE fiber, and carbon fiber; In step S1, according to weight percentage, the polyurethane prepolymer is 50%, the polyetheretherketone is 30%, the particle reinforcement material is 13%, and the fiber reinforcement material is 7%.

7. The method for preparing a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure according to claim 5, characterized in that: In step S3, the adhesive is one or more of flexible epoxy resin, polyurethane, silicone rubber, and acrylate; The functional additive is one or more of nano titanium dioxide, magnetic nanoparticles, and zinc oxide nanoparticles.

8. The method for preparing a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure according to claim 5, characterized in that: In step S4, the spraying thickness is between 0.5-1 mm; The formula ratio of the protective coating is 45% polyurethane acrylate resin, 30% silicone modified epoxy resin, 8% dicyandiamide curing agent, 7% isophorone diisocyanate curing agent, 5% aluminum powder, 2% titanium dioxide powder, 2% boron nitride powder, 1% leveling agent, 1% defoaming agent, and 1% dispersant.

9. The method for preparing a bionic muscle fiber negative Poisson's ratio geotechnical metamaterial structure according to any one of claims 5 to 8, characterized in that: In step S1, the grinding time of the base polymer matrix material and the reinforcing material is 1h-1.5h; When the grinding is complete, add it to the high-speed blender and blend at 2000 revolutions per minute for 30 minutes.

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