Porous cells with negative poisson's ratio effect, internal support structure of pipes and method for manufacturing same

Abstract

The present application belongs to the technical field of pipeline repair, and discloses a pore cell with a negative Poisson's ratio effect, wherein the pore cell is a remaining part of an equilateral triangle after being sheared by three half ellipses; one of the long axis vertices of each half ellipse coincides with a vertex of one side of the equilateral triangle, and the other long axis vertex of each half ellipse is located on the side of the equilateral triangle; each half ellipse has intersection points with other sides of the equilateral triangle; the long axis and the short axis of the three half ellipses are equal, but the three half ellipses do not intersect with each other on the equilateral triangle. The pore cell designed in the present application has a negative Poisson's ratio effect, and different shapes and different stiffnesses of the pore cell can be obtained by adjusting the length of the long axis and the short axis of the half ellipse in the pore cell, so as to realize the adjustability of the stiffness of the internal support structure of the pipeline, and the internal support structure of the pipeline with different diameters can be obtained by adjusting the size of the equilateral triangle in the pore cell, so as to adapt to the size of different types of pipelines to be repaired.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of pipeline repair, and relates to a pore cell with a negative Poisson's ratio effect, a pipeline internal support structure and a manufacturing method thereof. BACKGROUND

[0002] Municipal pipelines are one of the important projects of urban infrastructure, among which drainage pipelines are mainly used for timely collection and discharge of domestic sewage, industrial wastewater and rainwater to ensure the environmental sanitation of the city and the safety of people's life and property. The drainage pipeline is generally made of concrete, metal or plastic. After the pipeline is used for a certain period of time, structural peeling may occur on the inner wall surface of the pipeline, causing the pipeline wall to thin out or even locally collapse, resulting in pipeline blockage and water leakage, which seriously affects the urban environmental sanitation and threatens the safety of life and property.

[0003] The cured-in-place pipe (CIPP) repair technology is a particularly important repair technology in the current trenchless pipeline repair technology. Its repair principle is: first, lay a soft tube soaked with resin into the pipeline to be repaired through the corresponding equipment, then bundle one end of the soft tube, and inflate from the other end of the soft tube to make the soft tube expand so that the outer wall of the soft tube is attached to the inner wall of the pipeline to be repaired, then put a chain of ultraviolet lamps into the expanded soft tube, and use the irradiation of the ultraviolet lamps to make the soft tube solidify, and finally form a new continuous pipeline with full structural strength inside the pipeline to be repaired. This repair technology has the advantages of fast construction speed, short construction period, no influence on the surrounding environment, continuous lining pipe and smooth surface, etc.

[0004] At present, the CIPP pipeline repair technology in China is gradually mature, but there are still many problems to be solved and breakthroughs to be made. On the one hand, most of the current domestic trenchless pipeline repair technologies use on-site pipeline material photocuring for repair and update, which is slow. Different 3D printing materials can make the printed objects exhibit different mechanical properties. These printed components with excellent mechanical properties have been applied in the fields of medical treatment, aerospace, sensors, etc. If the pipeline repair support structure is printed in advance through 3D printing technology, it can more accurately and quickly support and repair the local pipeline. On the other hand, the forming material stiffness value of the current trenchless repair technology for pipeline repair has been limited, and it is usually difficult to adjust its mechanical properties. Negative Poisson's ratio material belongs to metamaterial, which has the performance of lateral expansion under axial tension and lateral contraction under axial compression. Compared with positive Poisson's ratio material, negative Poisson's ratio material can exhibit better ductility and adjustability. Many pore structures with negative Poisson's ratio are used in the fields of medical treatment, aviation and safety protection. If prefabricated components with negative Poisson's ratio effect are used as the support structure of the repaired pipeline, the stiffness of the pipeline support can be adjusted. However, there is no report on the application of structures with negative Poisson's ratio effect in the field of pipeline repair. SUMMARY

[0005] The present application aims at the technical problems of slow repair speed and difficulty in adjusting the mechanical parameters of repair materials in trenchless pipe repair technology, and provides a pore cell with a negative Poisson's ratio effect, different shapes and different rigidities of the pore cell are obtained by adjusting the length of the major axis and the minor axis of the semi-ellipse in the pore cell, the adjustability of the rigidity of the internal support structure of the pipe is realized, and the internal support structure of the pipe obtained by stretching, splicing and rotating the pore cell can be prefabricated by 3D printing technology, so that the pipe repair speed is improved.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0007] The present application provides a pore cell with a negative Poisson's ratio effect, the pore cell is the remaining part of an equilateral triangle after being sheared by three semi-ellipses, one of the major axis vertices of each semi-ellipse coincides with the vertex of one side of the equilateral triangle, the other major axis vertex of each semi-ellipse is located on the side of the equilateral triangle, each semi-ellipse has intersection points with other sides of the equilateral triangle, the major axis and the minor axis of the three semi-ellipses are equal, but the three semi-ellipses do not intersect each other on the equilateral triangle.

[0008] In one technical solution, the side length of the equilateral triangle is L, the length of the major axis of the semi-ellipse is , the distance between the major axis vertex of the semi-ellipse located on the side of the equilateral triangle and the vertex of the other side of the equilateral triangle is , that is, , and satisfies: .

[0009] In one technical solution, the length of the minor axis of the semi-ellipse is c, the distance between the major axis vertex of the semi-ellipse located on the side of the equilateral triangle and the intersection point of the other semi-ellipse and the side of the equilateral triangle is b, that is, b , and satisfies , .

[0010] The present application also provides an internal support structure of a pipe, which is a three-dimensional tubular pore structure obtained by stretching, splicing and rotating the above-mentioned pore cell with a negative Poisson's ratio effect.

[0011] In one technical solution, the thickness t of the three-dimensional tubular pore structure must satisfy: .

[0012] In one technical solution, the radius R of the three-dimensional tubular pore structure must satisfy: .

[0013] In one technical solution, the length h of the three-dimensional tubular pore structure must satisfy: .

[0014] The application also provides a manufacturing method of the pipeline internal support structure, comprising the following steps:

[0015] 1) determining the parameters of the pore cell of the pipeline internal support structure according to the size of the actual pipeline to be repaired;

[0016] 2) obtaining the three-dimensional tubular pore structure through stretching, splicing and rotating of the pore cell;

[0017] 3) selecting the 3D printing material according to the pipeline environment to be repaired, setting the 3D printing parameters, and 3D printing to obtain the pipeline internal support structure preform.

[0018] Compared with the prior art, the application has the following beneficial effects:

[0019] The pore cell designed in the application exhibits a negative Poisson's ratio effect in axial stretching and compression, and different pore cells with different shapes and stiffness can be obtained by adjusting the length of the major axis and the minor axis of the semi-ellipse in the pore cell, so as to realize the adjustability of the stiffness of the pipeline internal support structure. Different pipeline internal support structures with different diameters can be obtained by adjusting the size of the equilateral triangle in the pore cell, so as to adapt to the sizes of different types of pipelines to be repaired. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The figure is a schematic diagram of the design parameters of the pore cell of the application.

[0021] Figure 2 The figure is a structural schematic diagram of the pore cell of the application.

[0022] Figure 3 The figure is a structural schematic diagram of the pore cell of the application.

[0023] Figure 4 The figure is a structural schematic diagram of the pore cell of the application.

[0024] Figure 5 The figure is a structural schematic diagram of the pore cell of the application. DETAILED DESCRIPTION

[0025] The following examples are used to illustrate the application, but are not used to limit the protection scope of the application. If not specifically indicated, the technical means used in the examples are conventional means known to those skilled in the art. The test methods in the following examples are conventional methods, unless otherwise specified.

[0026] Example 1

[0027] The pore cell of this invention, exhibiting a negative Poisson's ratio effect, is the remaining portion of an equilateral triangle after being sheared by three semi-ellipses. One major axis vertex of each semi-ellipse coincides with one vertex of a side of the equilateral triangle it belongs to; the other major axis vertex of each semi-ellipse lies on a side of the equilateral triangle; each semi-ellipse intersects with the other sides of the equilateral triangle; the major and minor axes of the three semi-ellipses are equal, but the three semi-ellipses do not intersect each other on the equilateral triangle. The design parameters of the pore cell are as follows: Figure 1 As shown. The side length of the equilateral triangle is L, and the length of the major axis of the semi-ellipse is... In a semiellipse, the distance between the vertex of the major axis located on the side of an equilateral triangle and the vertex on the other side of that equilateral triangle is... ,Right now And satisfy: The minor axis of the semiellipse is of length c. The distance from the vertex of the major axis of the semiellipse located on the side of the equilateral triangle to the intersection point of the semiellipse and the side of the equilateral triangle is b, i.e., b < c. And satisfy , .

[0028] Figure 2 Four different shapes of pore cells are shown. Figure 2-1 The corresponding equilateral triangle has side lengths L=11.336mm, L1=7mm, L2=4.336mm, c=2mm, and b=3.965mm. Figure 2-2 The corresponding equilateral triangle has side lengths L=11.336mm, L1=7mm, L2=4.336mm, c=3mm, and b=3.528mm. Figure 2-3 The corresponding equilateral triangle has side lengths L=11.336mm, L1=6.2mm, L2=5.136mm, c=2mm, and b=4.088mm; Figure 2-4 The corresponding equilateral triangle has side lengths L=11.336mm, L1=6.2mm, L2=5.136mm, c=3mm, and b=3.518mm.

[0029] Once the size of the pore cell is determined, a pore unit is obtained by assembling the pore cells, such as... Figure 3 As shown; multiple pore units are spliced ​​together to form a planar pore structure, such as Figure 4 As shown; pore cells are stretched, spliced, and rotated to obtain a three-dimensional tubular pore structure, such as... Figure 5 As shown, the thickness t of the three-dimensional tubular porous structure must satisfy: The radius R must satisfy: The length h must satisfy: .

[0030] Example 2

[0031] A method for manufacturing a pipeline internal support structure, comprising the following steps:

[0032] 1) determining the parameters of the pore cell of the pipeline internal support structure according to the size of the actual pipeline to be repaired;

[0033] 2) obtaining a three-dimensional tubular pore structure through stretching, splicing and rotating of the pore cell;

[0034] 3) selecting a 3D printing material according to the pipeline environment to be repaired, setting 3D printing parameters, and 3D printing to obtain a pipeline internal support structure preform.

[0035] The above-described embodiments are only preferred embodiments of the present application, merely used to explain the present application, and are not intended to limit the scope of the present application. For those skilled in the art, of course, other embodiments can be easily made by substitution or change according to the technical content disclosed in the present specification. Therefore, any changes and improvements made on the principle of the present application shall be included in the scope of the patent application.

Claims

1. A porous cell having a negative Poisson's ratio effect, characterized in that, The hole cell is a positive triangle after being cut by three half ellipses, one long axis of each half ellipse coincides with the vertex of the side of the positive triangle, the other long axis of each half ellipse is on the side of the positive triangle, each half ellipse intersects with other sides of the positive triangle, the long axis and the short axis of the three half ellipses are equal, and the three half ellipses do not intersect with each other on the positive triangle.

2. The cellular unit with negative Poisson's ratio effect according to claim 1, wherein, The equilateral triangle has a side length of L, the major axis of the semi-ellipse has a length of L1, the distance from the vertex of the major axis of the semi-ellipse to the vertex of the other side of the equilateral triangle is L2, i.e. L1+L2=L, and the following conditions are satisfied:

3. The cellular unit with negative Poisson's ratio effect according to claim 1, wherein, The short axis length of the semi-ellipse is c, the distance between the long axis vertex on the edge of the equilateral triangle and the intersection point of the other semi-ellipse and the edge of the equilateral triangle is b, i.e. b < L2, and satisfies 4. A pipe internal support structure, characterized by, The pipe internal support structure is a three-dimensional tubular hole structure obtained by stretching, splicing and rotating the hole cell with a negative Poisson's ratio effect according to any one of claims 1-3.

5. A pipe internal support structure according to claim 4, wherein, The thickness t of the three-dimensional tubular pore structure must satisfy:

6. A pipe internal support structure according to claim 4, wherein, The radius R of the three-dimensional tubular pore structure must satisfy:

7. A pipe internal support structure according to claim 4, wherein, The length h of the three-dimensional tubular hole structure satisfies: h >= 2R.

8. A method of manufacturing a pipe internal support structure according to any one of claims 4 to 7, characterised in that, The method comprises the following steps: 1) determining the parameters of the hole cell of the pipe internal support structure according to the size of the actual pipe to be repaired; 2) obtaining a three-dimensional tubular hole structure by stretching, splicing and rotating the hole cell; 3) selecting a 3D printing material according to the pipe environment to be repaired, setting 3D printing parameters, and 3D printing to obtain a pipe internal support structure preform.

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