Multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure and manufacturing method thereof

Abstract

The invention discloses a multistage negative Poisson's ratio geotechnical vibration reduction and isolation structure and a manufacturing method thereof.The vibration reduction and isolation structure comprises a plurality of negative Poisson's ratio units (10) which are sequentially connected in the transverse direction (X) and the longitudinal direction (Y), and each negative Poisson's ratio unit (10) comprises two first transverse rods (11) which extend in the transverse direction (X) and are arranged in the longitudinal direction (Y) at intervals; the at least two first longitudinal rod assemblies (12) are connected between the two first transverse rods (11), each first longitudinal rod assembly (12) comprises at least two first longitudinal rods (121), the at least two first longitudinal rods (121) are connected end to end in the longitudinal direction (Y), and an obtuse included angle is formed between every two adjacent first longitudinal rods (121); wherein each negative Poisson's ratio unit (10) is further internally provided with a self-similar negative Poisson's ratio unit (20), and the self-similar negative Poisson's ratio units (20) are connected to the first transverse rod (11).

Description

Technical Field

[0001] The invention relates to the field of civil engineering material science and technology, and in particular to a multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure and a manufacturing method thereof. Background Art

[0002] With the acceleration of urbanization, the development and utilization of underground space is becoming more and more extensive. However, during the construction process, especially in large infrastructure projects such as subways and tunnels, vibration and pressure problems caused by complex geological conditions are often encountered. Traditional vibration reduction and isolation materials and technologies are difficult to effectively solve these problems, especially in high compressive stress environments. Therefore, it is particularly important to develop a new material that can have both good vibration reduction and compression resistance. Summary of the invention

[0003] In response to the problems and needs raised above, this solution proposes a multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure and its manufacturing method. Due to the following technical features, it can achieve the above technical objectives and bring about many other technical effects.

[0004] One object of the present invention is to provide a multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure, comprising:

[0005] A plurality of negative Poisson's ratio units are sequentially connected along the transverse direction and the longitudinal direction, and each negative Poisson's ratio unit includes:

[0006] Two first cross bars extending in the transverse direction and spaced apart in the longitudinal direction;

[0007] At least two first longitudinal bar assemblies connected between the two first cross bars, each first longitudinal bar assembly comprising at least two first longitudinal bars, at least two first longitudinal bars being connected in the longitudinal direction, and an obtuse angle is formed between two adjacent first longitudinal bars;

[0008] Wherein, a self-similar negative Poisson's ratio unit is also arranged in each of the negative Poisson's ratio units, and the self-similar negative Poisson's ratio unit is connected to the first crossbar.

[0009] In this technical solution, that is to say, the two first cross bars in the structure of the multiple negative Poisson's ratio units bear external forces, and since at least two first longitudinal bars in the first longitudinal bar assembly are at an obtuse angle, the first longitudinal bar assembly located between the two first cross bars can effectively buffer the external impact force, and a multi-level self-similar negative Poisson's ratio unit structure is embedded in the multi-level negative Poisson's ratio unit structure to achieve a multi-level shock absorption and compression resistance effect; this vibration reduction and isolation structure significantly improves the vibration reduction and compression resistance of the foundation, and is suitable for a variety of engineering application scenarios. Through the multi-level negative Poisson's ratio design, the material can still maintain good structural stability and recovery ability when subjected to high compressive stress, so that it can still show excellent vibration reduction effect under vibrations of different frequencies.

[0010] In addition, the multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure and its manufacturing method according to the present invention may also have the following technical features:

[0011] In an example of the present invention, two self-similar negative Poisson's ratio units are arranged in each of the negative Poisson's ratio units, and each of the self-similar negative Poisson's ratio units is fixedly connected to the first crossbar.

[0012] In one example of the present invention, the self-similar negative Poisson's ratio unit includes:

[0013] Two second crossbars extending in the transverse direction and spaced apart in the longitudinal direction, wherein the two second crossbars are arranged on both sides of the first crossbar;

[0014] At least two second longitudinal rod assemblies are connected between two of the second cross rods, each second longitudinal rod assembly includes at least two second longitudinal rods, at least two second longitudinal rods are connected to each other in the longitudinal direction, and an obtuse angle is formed between two adjacent second longitudinal rods.

[0015] In an example of the present invention, a plurality of self-similar negative Poisson's ratio units that are reduced in size are arranged inside the self-similar negative Poisson's ratio unit, and each reduced self-similar negative Poisson's ratio unit is connected to the second crossbar of the corresponding self-similar negative Poisson's ratio unit.

[0016] Another object of the present invention is to provide a method for manufacturing the multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure as described above, comprising the following steps:

[0017] S10: Put the high-performance polyurethane prepolymer as the basic polymer matrix material into a ball mill for powder grinding, and grind the particle reinforcement material and fiber reinforcement material as the reinforcement material and the high elastic material as the toughening agent separately, and the grinding time is 1h-1.5h;

[0018] S20: adding high-performance polyurethane prepolymer, particle reinforcement material, fiber reinforcement material and high elastic material powder into a high shear mixer for mixing, and adding additives during the mixing process, and the mixing time is 2 hours;

[0019] S30: using selective laser sintering 3D printing technology to prepare in one go a multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure as described in any one of claims 1 to 3;

[0020] S40: After the solid object is cooled and solidified, a protective coating is applied on the surface using a high-pressure airless spraying method with a spraying thickness between 0.5-1mm.

[0021] In one example of the present invention,

[0022] The particle reinforcement material comprises: one of carbon nanotubes, graphene and nano-alumina;

[0023] The fiber reinforcement material comprises: one of aramid fiber, UHMWPE fiber and carbon fiber;

[0024] The high elastic material includes: one of thermoplastic polyurethane elastomer and polyether block amide.

[0025] In one example of the present invention, in the step S20, high-performance polyurethane prepolymer, particle reinforcement material, fiber reinforcement material and high elastic material powder are added to a high shear mixer for mixing, wherein the addition amount of the high-performance polyurethane prepolymer is 50-55% of the total weight, the addition amount of the particle reinforcement material is 1.5-2% of the total weight, the addition amount of the fiber reinforcement material is 10-15% of the total weight, and the addition amount of the high elastic material is 5-8% of the total weight.

[0026] In one example of the present invention, in step S20, the additives include an anti-aging agent, a silane coupling agent and a micron-sized silica filler, the anti-aging agent accounts for 0.5-1% of the total weight, the silane coupling agent accounts for 0.5-1% of the total weight, and the micron-sized silica filler accounts for 3-5% of the total weight.

[0027] In one example of the present invention, in step S40, the components of the protective coating are 50% epoxy resin, 20% polyurethane, 10% amine curing agent, 10% isocyanate curing agent, 5% zinc powder, 2% titanium dioxide, 2% quartz powder, 0.5% leveling agent, 0.5% defoaming agent, and 0.5% dispersant.

[0028] In an example of the present invention, in the step S40, when the protective coating material is mixed, the epoxy resin and the polyurethane are first mixed evenly according to the formula ratio; then the amine curing agent and the isocyanate curing agent are added respectively and stirred evenly; finally, other additives are added.

[0029] The best embodiment for carrying out the present invention will be described in more detail below with reference to the accompanying drawings so that the features and advantages of the present invention can be easily understood. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings of the embodiments of the present invention, wherein the drawings are only used to illustrate some embodiments of the present invention, but not to limit all embodiments of the present invention thereto.

[0031] Figure 1 Schematic diagram of a multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure according to an embodiment of the present invention;

[0032] Figure 2 for Figure 1 A partial enlarged view of the middle Q;

[0033] Figure 3 for Figure 1 A partial enlarged view of the middle W;

[0034] Figure 4 is a curve diagram showing the effect of the amount of added particle reinforcement material on the flexural strength and compressive strength of the vibration reduction and isolation material according to an embodiment of the present invention;

[0035] Figure 5 is a curve diagram showing the effect of the amount of fiber reinforcement material added on the flexural strength and compressive strength of the vibration reduction and isolation material according to an embodiment of the present invention;

[0036] Figure 6 A curve diagram showing the influence of the amount of plasticizer added on the relative ductility of the multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation material according to an embodiment of the present invention;

[0037] FIG. 7( a ) is a schematic diagram of a first-level negative Poisson's ratio geosynthetic vibration reduction and isolation structure according to an embodiment of the present invention;

[0038] FIG7( b ) is a schematic diagram of a secondary negative Poisson's ratio geosynthetic vibration reduction and isolation structure according to an embodiment of the present invention;

[0039] FIG7( c ) is a schematic diagram of a three-level negative Poisson's ratio geosynthetic vibration reduction and isolation structure according to an embodiment of the present invention;

[0040] FIG7( d ) is a schematic diagram of a four-level negative Poisson's ratio geosynthetic vibration reduction and isolation structure according to an embodiment of the present invention;

[0041] FIG7( e ) is a schematic diagram of a five-level negative Poisson's ratio geosynthetic vibration reduction and isolation structure according to an embodiment of the present invention;

[0042] FIG7( f ) is a schematic diagram of a six-level negative Poisson's ratio geosynthetic vibration reduction and isolation structure according to an embodiment of the present invention;

[0043] Figure 8 4 is a curve diagram showing the relationship between the relative compressive strength and the multi-level negative Poisson's ratio according to an embodiment of the present invention.

[0044] List of reference numerals:

[0045] Vibration reduction and isolation structure 100;

[0046] Negative Poisson's ratio unit 10;

[0047] A first crossbar 11;

[0048] A first longitudinal rod assembly 12;

[0049] A first longitudinal rod 121;

[0050] Self-similar negative Poisson's ratio unit 20;

[0051] A second crossbar 21;

[0052] A second longitudinal rod assembly 22;

[0053] A second longitudinal rod 221;

[0054] Horizontal direction X;

[0055] Longitudinal direction Y. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical solution and advantages of the technical solution of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in conjunction with the drawings of specific embodiments of the present invention. The same figure marks in the drawings represent the same parts. It should be noted that the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] Unless otherwise defined, the technical terms or scientific terms used herein shall have the common meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not necessarily indicate quantity restrictions. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0058] A multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure 100 according to the first aspect of the present invention comprises:

[0059] A plurality of negative Poisson's ratio units 10 are sequentially connected along the transverse direction X and the longitudinal direction Y, and each negative Poisson's ratio unit 10 comprises:

[0060] Two first cross bars 11 extending in the transverse direction X and spaced apart in the longitudinal direction Y;

[0061] At least two first longitudinal rod assemblies 12 connected between the two first cross rods 11, each first longitudinal rod assembly 12 includes at least two first longitudinal rods 121, at least two first longitudinal rods 121 are connected in the longitudinal direction Y, and an obtuse angle is formed between two adjacent first longitudinal rods 121;

[0062] A self-similar negative Poisson's ratio unit 20 is further provided in each of the negative Poisson's ratio units 10 , and the self-similar negative Poisson's ratio unit 20 is connected to the first crossbar 11 .

[0063] That is to say, the two first cross bars 11 in the structure of the multiple negative Poisson's ratio units 10 bear external forces, and since at least two first longitudinal bars 121 in the first longitudinal bar assembly 12 are at an obtuse angle, the first longitudinal bar assembly 12 located between the two first cross bars 11 can effectively buffer the external impact force, and the multi-stage self-similar negative Poisson's ratio unit 20 structure is embedded in the multi-stage negative Poisson's ratio unit 10 structure to achieve the multi-stage shock absorption and compression resistance effect; the vibration reduction and isolation structure 100 significantly improves the vibration reduction performance and compression resistance of the foundation, and is suitable for a variety of engineering application scenarios. Through the multi-stage negative Poisson's ratio design, the material can still maintain good structural stability and recovery ability when subjected to high compressive stress, so that it can still show excellent vibration reduction effect under vibrations of different frequencies.

[0064] Preferably, since the negative Poisson's ratio units 10 are sequentially connected in the transverse direction X and the longitudinal direction Y, the first longitudinal rod 121 and the first transverse rod 11 can be shared.

[0065] In one example of the present invention, two self-similar negative Poisson's ratio units 20 are arranged in each of the negative Poisson's ratio units 10, and each of the self-similar negative Poisson's ratio units 20 is fixedly connected to the first crossbar 11;

[0066] That is to say, each negative Poisson's ratio unit 10 is further provided with a self-similar negative Poisson's ratio unit 20 similar thereto, thereby achieving a multi-level shock-absorbing and pressure-resistant effect.

[0067] In one example of the present invention, the self-similar negative Poisson's ratio unit 20 includes:

[0068] Two second cross bars 21 extending in the transverse direction X and spaced apart in the longitudinal direction Y, wherein the two second cross bars 21 are disposed on both sides of the first cross bar 11;

[0069] At least two second longitudinal rod assemblies 22 connected between the two second cross rods 21, each second longitudinal rod assembly 22 includes at least two second longitudinal rods 221, at least two first longitudinal rods are connected in the longitudinal direction Y, and an obtuse angle is formed between two adjacent first longitudinal rods;

[0070] For example, FIG. 7( a ) shows a primary shock absorbing structure: it includes a plurality of negative Poisson's ratio units 10, which are sequentially connected along the transverse direction X and the longitudinal direction Y, and each negative Poisson's ratio unit 10 includes:

[0071] Two first cross bars 11 extending in the transverse direction X and spaced apart in the longitudinal direction Y;

[0072] At least two first longitudinal rod assemblies 12 are connected between the two first cross rods 11, each first longitudinal rod assembly 12 includes at least two first longitudinal rods 121, at least two first longitudinal rods 121 are connected in the longitudinal direction Y, and an obtuse angle is formed between two adjacent first longitudinal rods 121.

[0073] In one example of the present invention, a plurality of self-similar negative Poisson's ratio units 20 that are smaller than the same period are further arranged inside the self-similar negative Poisson's ratio unit 20, and each of the smaller self-similar negative Poisson's ratio units 20 is connected to the second crossbar 21 of the corresponding self-similar negative Poisson's ratio unit 20;

[0074] For example, as shown in FIG. 7( b ), a secondary shock absorbing structure is provided, based on the primary shock absorbing structure, a self-similar negative Poisson's ratio unit 20 is provided inside the structure, and the self-similar negative Poisson's ratio unit 20 includes:

[0075] Two second cross bars 21 extending in the transverse direction X and spaced apart in the longitudinal direction Y, wherein the two second cross bars 21 are disposed on both sides of the first cross bar 11;

[0076] At least two second longitudinal rod assemblies 22 are connected between two of the second cross rods 21 , each second longitudinal rod assembly 22 includes at least two second longitudinal rods 221 , at least two second longitudinal rods 221 are connected in the longitudinal direction Y, and an obtuse angle is formed between two adjacent second longitudinal rods 221 .

[0077] By analogy, the shock absorbing structure of the three-stage straight six-stage is as follows Figure 7(c) to Figure 7(f) As shown, no further description is given here.

[0078] According to the second aspect of the present invention, a method for manufacturing the multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure 100 as described above comprises the following steps:

[0079] S10: Put the high-performance polyurethane prepolymer as the basic polymer matrix material into a ball mill for powder grinding, and grind the particle reinforcement material and fiber reinforcement material as the reinforcement material and the high elastic material as the toughening agent separately, and the grinding time is 1h-1.5h;

[0080] S20: adding high-performance polyurethane prepolymer, particle reinforcement material, fiber reinforcement material and high elastic material powder into a high shear mixer for mixing, and adding additives during the mixing process, and the mixing time is 2 hours;

[0081] S30: using selective laser sintering 3D printing technology to prepare and form the multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure 100 as described in any one of claims 1 to 3 in one go;

[0082] S40: After the solid object is cooled and solidified, a protective coating is applied on the surface using a high-pressure airless spraying method with a spraying thickness between 0.5-1mm.

[0083] The material preparation method provided by the present invention significantly improves the vibration reduction performance and compression resistance of the foundation, and is suitable for a variety of engineering application scenarios. Through formula optimization and multi-level negative Poisson's ratio design, the material can still maintain good structural stability and recovery ability when subjected to high compressive stress, so that it can still show excellent vibration reduction effect under vibrations of different frequencies. The use of SLS3D printing technology simplifies the manufacturing process, reduces production costs, reduces the impact on the environment, meets the requirements of sustainable development, and provides an efficient, durable, and environmentally friendly solution for the construction of underground space, promoting technological progress in the field of civil engineering.

[0084] In one example of the present invention,

[0085] The particle reinforcement material comprises: one of carbon nanotubes, graphene and nano-alumina;

[0086] The fiber reinforcement material comprises: one of aramid fiber, UHMWPE fiber and carbon fiber;

[0087] The high elastic material includes: one of thermoplastic polyurethane elastomer and polyether block amide.

[0088] In one example of the present invention, in the step S20, high-performance polyurethane prepolymer, particle reinforcement material, fiber reinforcement material and high elastic material powder are added to a high shear mixer for mixing, wherein the addition amount of the high-performance polyurethane prepolymer is 50-55% of the total weight, the addition amount of the particle reinforcement material is 1.5-2% of the total weight, the addition amount of the fiber reinforcement material is 10-15% of the total weight, and the addition amount of the high elastic material is 5-8% of the total weight.

[0089] For example, a high-performance polyurethane prepolymer (PU) is used as a basic polymer matrix material and is put into a planetary ball mill for powder grinding, and carbon nanotubes (CNTs) and aramid fibers are used as reinforcing materials, and thermoplastic polyurethane elastomer (TPU) is used as a toughening agent and are ground separately for a grinding time of 1 h to 1.5 h, so that each material is fully ground; high-performance polyurethane prepolymer (PU), carbon nanotubes (CNTs), aramid fibers and thermoplastic polyurethane elastomer (TPU) powders are added to a high shear mixer for mixing, and during the mixing process, additives are added and fully mixed for a mixing time of 2 h; wherein the proportions of the mixed components are 50-55% high-performance polyurethane prepolymer (PU), 1.5-2% carbon nanotubes (CNTs), 10-15% aramid fibers, 5-8% plastic polyurethane elastomer (TPU), and 4-7% additives.

[0090] In one example of the present invention, in step S20, the additives include an anti-aging agent, a silane coupling agent and a micron-sized silica filler, the anti-aging agent accounts for 0.5-1% of the total weight, the silane coupling agent accounts for 0.5-1% of the total weight, and the micron-sized silica filler accounts for 3-5% of the total weight.

[0091] In one example of the present invention, in step S40, the components of the protective coating are 50% epoxy resin, 20% polyurethane, 10% amine curing agent, 10% isocyanate curing agent, 5% zinc powder, 2% titanium dioxide, 2% quartz powder, 0.5% leveling agent, 0.5% defoaming agent, and 0.5% dispersant.

[0092] In an example of the present invention, in the step S40, when the protective coating material is mixed, the epoxy resin and the polyurethane are first mixed evenly according to the formula ratio; then the amine curing agent and the isocyanate curing agent are added respectively and stirred evenly; finally, other additives are added.

[0093] Specific examples

[0094] A method for manufacturing a multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure 100 comprises the following steps:

[0095] S10: Put high-performance polyurethane prepolymer (PU) as the basic polymer matrix material into a planetary ball mill for powder grinding, and grind carbon nanotubes (CNTs) and aramid fibers as reinforcing materials and thermoplastic polyurethane elastomer (TPU) as a toughening agent separately for 1h-1.5h to ensure that each material is fully ground;

[0096] S20: Add high-performance polyurethane prepolymer (PU), carbon nanotubes (CNTs), aramid fiber and thermoplastic polyurethane elastomer (TPU) powder into a high shear mixer for mixing, and add additives during the mixing process, mix thoroughly and evenly, and the mixing time is 2 hours; the proportion of each component is 50-55% high-performance polyurethane prepolymer (PU), 1.5-2% carbon nanotubes (CNTs), 10-15% aramid fiber, 5-8% plastic polyurethane elastomer (TPU), 4-7% additive; aramid fiber as a fiber reinforcement material can be replaced by UHMWPE fiber, carbon fiber and other fiber reinforcement materials; thermoplastic polyurethane elastomer (TPU) as a toughening agent can be replaced by high elastic materials such as polyether block amide (PEBA); the additives include anti-aging machine, silane coupling agent, micron-sized silica filler. During the period, the aging machine contains antioxidants and light stabilizers, accounting for 0.5-1% of the total weight ratio, silane coupling agents accounting for 0.5-1% of the total weight ratio, and micron-sized silica fillers accounting for 3-5% of the total weight ratio;

[0097] Figure 4 The curve of the influence of the addition amount of particle reinforcement material on the flexural strength and compressive strength of multi-level negative Poisson's ratio geosynthetic vibration reduction and isolation materials is shown in the figure. As shown in the figure, when the addition amount of particle reinforcement material gradually increases, the relative flexural strength increases. After the addition amount exceeds 2%, the growth rate gradually slows down, and the increase in relative compressive strength is not greatly affected. Therefore, the content of particle reinforcement material is selected to be before 1.5-2%;

[0098] Figure 5 The influence curve of the addition amount of fiber reinforcement material on the flexural strength and compressive strength of multi-level negative Poisson's ratio geosynthetic vibration reduction and isolation material is shown in the figure. As shown in the figure, when the addition amount of fiber reinforcement material gradually increases, the relative flexural strength gradually increases, while the relative compressive strength first increases and then decreases. After the addition amount exceeds 14%, the relative increase in strength has a downward trend. Therefore, according to Figure 5 As shown, the amount of fiber reinforcement added is 10-15%;

[0099] Figure 6 This is the influence curve of the amount of plasticizer added on the relative ductility of the multi-level negative Poisson's ratio geosynthetic vibration reduction and isolation material. As shown in the figure, when the amount of plasticizer added gradually increases, the relative bending strength gradually increases. After the amount added exceeds 8%, the relative ductility tends to decrease. Therefore, according to the figure, the amount of toughener added is 5-8%;

[0100] S30: It is manufactured in one go using the 3D printing technology of Selective Laser Sintering (SLS), and the multi-level negative Poisson's ratio design is accurately realized; the multi-level negative Poisson's ratio design is to embed a multi-level self-similar negative Poisson's ratio unit 20 structure in the unit structure to achieve the multi-level shock absorption and compression resistance effect;

[0101] like Figure 7(a)-Figure 7(f) As shown in the figure, it is a schematic diagram of a one-stage straight six-stage negative Poisson's ratio shock absorption structure. Figure 8 As shown in the figure, it is the relationship curve between relative compressive capacity and multi-level negative Poisson's ratio. Relative compressive capacity refers to the force that can be borne under unit deformation. When the number of levels gradually increases, the relative compressive capacity will gradually increase, but when it reaches the seventh level, the curve basically tends to be flat;

[0102] S40: After the solid material is cooled and solidified, a protective coating is applied on the surface by high-pressure airless spraying. After spraying, it is dried under natural conditions or heated in an oven to accelerate the curing process. The spraying thickness is between 0.5-1mm. The components of the coating are 50% epoxy resin, 20% polyurethane, 10% amine curing agent, 10% isocyanate curing agent, 5% zinc powder, 2% titanium dioxide, 2% quartz powder, 0.5% leveling agent, 0.5% defoaming agent, and 0.5% dispersant;

[0103] Among them, the process of high-pressure airless spraying process generally includes:

[0104] 1. Preparation: Make sure the surface to be sprayed is clean, free of oil, dust and other impurities. You can use solvent to wipe or high-pressure water to wash, and use sandpaper to polish the surface if necessary; mix the appropriate proportion according to the instructions of the paint, first mix the 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 to ensure the uniformity and reliability of the coating.

[0105] 2. Equipment preparation: Check the spraying equipment to ensure that the high-pressure airless sprayer is in good condition, the nozzle is clean and unblocked, and the high-pressure pipeline is leak-free; connect the power supply and compressed air source. Connect the sprayer to the power supply and ensure that the compressed air source works normally and provides sufficient air pressure; according to the characteristics of the paint and the spraying requirements, adjust the sprayer spray pressure to 3000psi (about 207bar), the flow rate to 0.4gpm (about 1.5L / min), the nozzle size to 0.015 inches (about 0.38 mm), and the spray width to 8 to 10 inches (about 20 to 25 cm).

[0106] 3. Formal spraying: Keep the nozzle at a 90-degree angle to the spraying surface to ensure uniform coverage of the paint. Usually the distance between the nozzle and the surface is kept between 20-30 cm, which is adjusted according to the spraying equipment and paint characteristics; maintain a uniform speed, avoid being too fast or too slow to prevent the coating from being too thin or too thick; each time you spray, ensure that adjacent sprays overlap to a certain extent (usually 50%) to ensure uniformity of the coating.

[0107] 4. Multi-layer spraying: spray multiple layers, making sure each layer is dry before spraying the next layer. Wait for an appropriate time (usually a few minutes to half an hour) according to the characteristics of the paint and environmental conditions; repeat the above steps as needed until the desired coating thickness is reached.

[0108] 5. Drying and curing: After spraying, let the coating dry and cure under natural conditions. Depending on the characteristics of the coating and environmental conditions, it usually takes several hours to a day. If you need to accelerate the curing process, you can put the sprayed workpiece in an oven and heat it at an appropriate temperature for curing. The specific temperature and time are adjusted according to the coating instructions.

[0109] 6. Inspection and repair: Check whether the coating is uniform and free of defects. If there are missed spraying or uneven coating, re-spraying or repair is required; evaluate the coating's adhesion, hardness and other performance indicators to ensure that they meet the requirements.

[0110] The exemplary implementation of the multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure 100 and its manufacturing method proposed in the present invention is described in detail above with reference to the 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-mentioned specific embodiments, and various technical features and structures proposed in the present invention can be combined in various ways without exceeding the protection scope of the present invention. The protection scope of the present invention is determined by the attached claims.

Claims

1. A multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure, characterized in that: include: A plurality of negative Poisson's ratio units (10) are connected in sequence along a transverse direction (X) and a longitudinal direction (Y), and each negative Poisson's ratio unit (10) comprises: Two first cross bars (11) extending in the transverse direction (X) and spaced apart in the longitudinal direction (Y); At least two first longitudinal rod assemblies (12) connected between the two first cross rods (11), each first longitudinal rod assembly (12) comprising at least two first longitudinal rods (121), the at least two first longitudinal rods (121) being connected to each other in the first position along the longitudinal direction (Y), and an obtuse angle is formed between two adjacent first longitudinal rods (121); Wherein, a self-similar negative Poisson's ratio unit (20) is also provided in each of the negative Poisson's ratio units (10), and the self-similar negative Poisson's ratio unit (20) is connected to the first crossbar (11).

2. The multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure according to claim 1 is characterized in that: Two self-similar negative Poisson's ratio units (20) are arranged in each of the negative Poisson's ratio units (10), and each of the self-similar negative Poisson's ratio units (20) is fixedly connected to the first crossbar (11).

3. The multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure according to claim 1 is characterized in that: The self-similar negative Poisson's ratio unit (20) comprises: two second cross bars (21) extending in the transverse direction (X) and arranged at intervals in the longitudinal direction (Y), wherein the two second cross bars (21) are arranged on both sides of the first cross bar (11); At least two second longitudinal rod assemblies (22) are connected between the two second cross rods (21), each second longitudinal rod assembly (22) comprises at least two second longitudinal rods (221), the at least two second longitudinal rods (221) are connected to each other in the first position along the longitudinal direction (Y), and an obtuse angle is formed between two adjacent second longitudinal rods (221).

4. The multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure according to claim 1 is characterized in that: A plurality of self-similar negative Poisson's ratio units (20) that are reduced in size compared to the same period are also arranged inside the self-similar negative Poisson's ratio unit (20), and each reduced self-similar negative Poisson's ratio unit (20) is connected to the second crossbar (21) of the corresponding self-similar negative Poisson's ratio unit (20).

5. A method for manufacturing a multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure as claimed in any one of claims 1 to 4, characterized in that: The steps include: S10: Put the high-performance polyurethane prepolymer as the basic polymer matrix material into a ball mill for powder grinding, and grind the particle reinforcement material and fiber reinforcement material as the reinforcement material and the high elastic material as the toughening agent separately, and the grinding time is 1h-1.5h; S20: adding high-performance polyurethane prepolymer, particle reinforcement material, fiber reinforcement material and high elastic material powder into a high shear mixer for mixing, and adding additives during the mixing process, and the mixing time is 2 hours; S30: using selective laser sintering 3D printing technology to prepare in one go a multi-stage negative Poisson's ratio geosynthetic vibration reduction and isolation structure (100) as described in any one of claims 1 to 3; S40: After the solid object is cooled and solidified, a protective coating is applied on the surface using a high-pressure airless spraying method with a spraying thickness between 0.5-1mm.

6. The method for manufacturing a multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure according to claim 5, characterized in that: The particle reinforcement material comprises: one of carbon nanotubes, graphene and nano-alumina; The fiber reinforcement material comprises: one of aramid fiber, UHMWPE fiber and carbon fiber; The high elastic material includes: one of thermoplastic polyurethane elastomer and polyether block amide.

7. The method for manufacturing a multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure according to claim 5, characterized in that: In the step S20, high-performance polyurethane prepolymer, particle reinforcement material, fiber reinforcement material and high elastic material powder are added to a high shear mixer for mixing, wherein the addition amount of the high-performance polyurethane prepolymer is 50-55% of the total weight, the addition amount of the particle reinforcement material is 1.5-2% of the total weight, the addition amount of the fiber reinforcement material is 10-15% of the total weight, and the addition amount of the high elastic material is 5-8% of the total weight.

8. The method for manufacturing a multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure according to claim 5, characterized in that: In step S20, the additives include an anti-aging agent, a silane coupling agent and a micron-sized silica filler, wherein the anti-aging agent accounts for 0.5-1% of the total weight, the silane coupling agent accounts for 0.5-1% of the total weight, and the micron-sized silica filler accounts for 3-5% of the total weight.

9. The method for manufacturing a multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure according to claim 5, characterized in that: In step S40, the components of the protective coating are 50% epoxy resin, 20% polyurethane, 10% amine curing agent, 10% isocyanate curing agent, 5% zinc powder, 2% titanium dioxide, 2% quartz powder, 0.5% leveling agent, 0.5% defoaming agent, and 0.5% dispersant.

10. The method for manufacturing a multi-stage negative Poisson's ratio geotechnical vibration reduction and isolation structure according to claim 5, characterized in that: In the step S40, when the protective coating material is mixed, the epoxy resin and the polyurethane are first mixed evenly according to the formula ratio; then the amine curing agent and the isocyanate curing agent are added respectively and stirred evenly; finally, other additives are added.

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