Container side panel composite structure and method of manufacture

Abstract

This disclosure presents a composite structure for a container side panel and its manufacturing method, relating to, but not limited to, the field of container technology. The composite structure uses wooden I-beams as the main supporting framework for the core material, forming a frame with multiple spaced-apart I-beams filled with foam. The wooden I-beams, while ensuring structural strength, significantly reduce the overall weight of the composite structure compared to traditional corrugated steel. The foam filling further enhances the integrity and stability of the core material structure, while also providing thermal insulation, sound insulation, and cushioning properties. The fiber-reinforced plastic layer in the skin provides the composite structure with good corrosion resistance, high specific strength and specific stiffness, and effectively protects the internal core material structure. Therefore, this composite structure achieves lightweight while possessing high strength, high rigidity, excellent corrosion resistance, and good thermal and sound insulation performance.

Description

Technical Field

[0001] This disclosure relates to, but is not limited to, the field of container technology, and in particular to a composite structure for container side panels and its preparation method. Background Technology

[0002] With the improvement of people's living standards and the abundance of material goods, transportation and logistics have become important factors affecting social development, stability, and the foundation. As one of the main carriers of transportation, container shipping plays a crucial role. Lightweighting the container structure can improve its carrying efficiency, reduce energy consumption and pollutant emissions from transportation equipment, and is of great significance.

[0003] Currently, the vast majority of existing container side panels are made of corrugated steel. Corrugated steel has disadvantages such as high density, poor corrosion resistance, and low manufacturing and design flexibility, which leads to increased container transportation and maintenance costs. Summary of the Invention

[0004] The purpose of this disclosure is to propose a composite structure for container side panels and a method for its preparation, which aims to solve the problem of increased container transportation and maintenance costs caused by existing container side panels.

[0005] In a first aspect, embodiments of this disclosure provide a container side panel composite structure, the composite structure comprising: a core material structural layer, the core material structural layer including a plurality of spaced-apart I-beam structural members and a foam structure located between adjacent I-beam structural members, wherein the I-beam structural members are made of wood; and The skin is disposed on the outside of the core material structural layer. The skin includes a fiber-reinforced plastic layer and a steel structure layer, and the fiber-reinforced plastic layer and the steel structure layer are stacked together.

[0006] According to a first aspect of the present disclosure, the composite structure uses wooden I-beams as the main supporting framework for the core material, and forms a frame using multiple spaced-apart I-beams, with foam filling the spaces between the I-beams. The wooden I-beams, while ensuring structural strength, significantly reduce the overall weight of the composite structure compared to traditional corrugated steel. Furthermore, the foam filling further enhances the integrity and stability of the core material structure layer, while also providing thermal insulation, sound insulation, and cushioning properties. In addition, the fiber-reinforced plastic layer in the skin provides the composite structure with good corrosion resistance, high specific strength and specific stiffness, and effectively protects the internal core material structure layer. Therefore, this composite structure achieves lightweighting while possessing high strength, high rigidity, excellent corrosion resistance, and good thermal and sound insulation properties, effectively solving the problems of high density, poor corrosion resistance, and low manufacturing and design flexibility of traditional corrugated steel structures, and effectively reducing container transportation and maintenance costs.

[0007] In some embodiments of the composite structure, the specific modulus of the wood material is greater than 15 GPa / (g / cm³). 3 ).

[0008] In some embodiments of the composite structure, the foamed structure is made of polystyrene.

[0009] In some embodiments of the composite structure, the fiber-reinforced plastic layer is a glass fiber / polypropylene layer; The glass fibers in the glass fiber / polypropylene layer are symmetrically laid out.

[0010] In some embodiments of the composite structure, there are multiple glass fiber / polypropylene layers, which are stacked together, and the glass fibers in adjacent glass fiber / polypropylene layers may have the same or different laying angles.

[0011] In some embodiments of the composite structure, the fiber-reinforced plastic layer is connected to the I-beam structure via the steel structural layer.

[0012] In some embodiments of the composite structure, the fiber-reinforced plastic layer is bonded to the steel structure layer.

[0013] In some embodiments of the composite structure, the I-beam structural member is bonded to the steel structural layer.

[0014] Secondly, embodiments of this disclosure provide a method for preparing a composite structure for a container side panel, the method comprising: Prepare a fiber-reinforced plastic layer and a steel structure layer, and stack the fiber-reinforced plastic layer and the steel structure layer together; Multiple I-beam structural components were fabricated using wood. Multiple I-beam structural members are spaced apart, and one side of each of the multiple I-beam structural members is connected to the steel structure layer; Fill the spaces between adjacent I-beam structural members with foam; and The other side of the plurality of I-beam structural members is connected to the steel structure layer.

[0015] In some embodiments of the method for preparing the container side panel composite structure, multiple I-beam structural members are connected to the steel structure layer by bonding.

[0016] Other features and advantages of this disclosure will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the disclosure. Other advantages of this disclosure may be realized and obtained by means of the methods described in the description and the accompanying drawings. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] in: Figure 1 This is a flowchart illustrating the method for preparing the composite structure of the container side panel in this embodiment of the present disclosure; Figure 2 This is a schematic diagram of the composite structure of the container side panel in one embodiment of the present disclosure; Figure 3 for Figure 2 Enlarged structural diagram of section A in the middle; Figure 4 This is a schematic diagram of the I-beam structure of the container side panel composite structure in one embodiment of the present disclosure; Figure 5 This is a schematic diagram of the container side panel composite structure after the skin has been removed in one embodiment of this disclosure; Figure 6 This is an enlarged structural schematic diagram showing the position of the I-beam structure of the container side panel composite structure in one embodiment of this disclosure; Figure 7 This is a force-displacement curve obtained from a three-point bending test on a mechanical testing machine for a container side panel composite structure in one embodiment of this disclosure.

[0019] Explanation of icon numbers: 100. Fiber-reinforced plastic layer; 200. I-beam structure; 300. Foamed structure; 400. Steel structure layer. Detailed Implementation

[0020] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0021] This disclosure provides a composite structure for container side panels and a method for its fabrication, aiming to achieve lightweight, high corrosion resistance, and high design flexibility for container side panels.

[0022] The following describes in detail, with reference to the accompanying drawings, a container side panel composite structure and its preparation method provided by the present disclosure.

[0023] See Figures 2 to 6 The composite structure in this embodiment includes a core material structural layer and a skin. The skin is disposed on the outside of the core material structural layer. This composite structure can replace traditional corrugated steel side panels, thereby forming the sidewall of a container.

[0024] In this embodiment, the core material structure layer includes a plurality of spaced-apart I-beam structural members 200 and a foam structure 300 located between adjacent I-beam structural members 200. The I-beam structural members 200 are made of wood.

[0025] For example, the wood material can be hard maple, cedar, pine, birch, oak, Indonesian merbau, or glued laminated timber made of multiple layers of veneer pressed together with adhesives. By using the wooden I-beam structural member 200 as the main supporting framework of the core material structural layer, the overall weight of the composite structure can be significantly reduced while ensuring good load-bearing and bending resistance.

[0026] See Figure 3 and Figure 6 In some embodiments, the skin includes a fiber-reinforced plastic layer 100 and a steel structure layer 400. The fiber-reinforced plastic layer 100 and the steel structure layer 400 are stacked. Exemplarily, the steel structure layer 400 can be made of high-manganese steel sheet with a thickness of 0.35 mm. The addition of the steel structure layer 400 can further improve the flexural modulus and impact toughness of the composite structure, enabling the composite structure to better adapt to the usage requirements of containers under harsh working conditions. Simultaneously, since the fiber-reinforced plastic layer 100 covers the outside of the steel structure layer 400, it can effectively prevent the steel structure layer 400 from corroding, thereby overcoming the poor corrosion resistance of traditional pure steel side panels. Furthermore, under the same flexural modulus and impact toughness conditions, the fiber-reinforced plastic layer 100 can effectively reduce the thickness of the steel structure layer 400, reducing the weight of the skin while ensuring flexural modulus and impact toughness.

[0027] In some embodiments, the specific modulus of wood is greater than 15 GPa / (g / cm³). 3 Specific modulus, the ratio of a material's elastic modulus to its density, is an important indicator of a material's lightweight nature. A specific modulus greater than 15 GPa / (g / cm³) is used. 3 The use of wood to construct the 200 I-beam structure allows for maximum weight reduction while maintaining structural rigidity. This helps to further improve the carrying efficiency of containers. Specifically, Indonesian Merbau wood can be used, which has a high specific modulus and good corrosion resistance.

[0028] In some embodiments, the height of the I-beam 200 can be approximately 39 mm; wherein the height direction is the thickness direction of the composite structure, and the width of the I-beam 200 can be approximately 36 mm or 7 mm (wherein the flange width is approximately 2 mm and the web width is approximately 3 mm), wherein the width direction is the length direction of the composite structure; the spacing between adjacent I-beams 200 can be approximately 600 mm. Of course, the above dimensions can be adjusted according to actual design requirements, and this disclosure does not impose any limitations on this. The I-beam 200, as a reinforcing rib structure, can achieve the purpose of reducing mass and improving bending stiffness.

[0029] Furthermore, the foam structure 300 can be made of any suitable low-density foam material, such as polyurethane foam, phenolic foam, etc. In some embodiments, the foam structure 300 is made of polystyrene. Polystyrene has advantages such as extremely low density, low thermal conductivity, low water absorption, and good sound insulation performance. For example, the density of the polystyrene foam structure 300 can be 0.016 g / cm³. The polystyrene foam structure 300 filled between the I-beam structural members 200 not only connects multiple discrete I-beam structural members 200 into a whole, enhancing the integrity and stability of the core material structural layer and providing a certain anti-tipping capability, but also effectively isolates the transmission of external heat and noise, improving the comfort of the container's internal environment. Moreover, when the container side panel composite structure is subjected to external impact, the foam structure 300 can also play a certain role in buffering and absorbing energy. Furthermore, the fiber-reinforced plastic layer 100 has excellent corrosion resistance, high specific strength and specific modulus, which can provide effective protection for the core material structure layer, protecting it from external moisture, chemicals and ultraviolet radiation, and significantly improving the overall mechanical properties of the composite structure.

[0030] In some embodiments, the fiber-reinforced plastic layer 100 is a glass fiber / polypropylene layer. Glass fiber / polypropylene composite material is a high-performance thermoplastic composite material with high strength and rigidity, as well as excellent impact resistance and fatigue resistance. Using a glass fiber / polypropylene layer as the skin allows the composite structure to perform more stably under dynamic loads. Simultaneously, the polypropylene matrix has good water resistance and chemical corrosion resistance, further improving the weather resistance of the composite structure. The density of the glass fiber / polypropylene layer is approximately 1.8 g / cm³, far lower than the density of steel (7.8 g / cm³), allowing it to replace corrugated steel and meet the lightweight requirements of container side panel structures. Furthermore, the glass fiber / polypropylene layer also possesses excellent properties such as chemical and seawater corrosion resistance, heat resistance, and processing adaptability, reducing the use and maintenance costs of container side panels. Exemplarily, the thickness of the glass fiber / polypropylene layer can be 0.3 mm or 0.9 mm. The fiber-reinforced plastic layer 100 can also be a carbon fiber / polypropylene layer.

[0031] In some embodiments, the glass fibers in the glass fiber / polypropylene layer are laid symmetrically. For example, the glass fibers can be laid at 0°, 45°, 90°, 90°, 45°, and 0°. Symmetrical laying prevents stress warping of the glass fiber / polypropylene layer. Furthermore, by adjusting the laying angle of the glass fibers, the mechanical properties of the skin in different directions can be flexibly designed, allowing it to better adapt to the complex stress states experienced by the container during lifting, stacking, and transportation.

[0032] In some embodiments, there are multiple glass fiber / polypropylene layers, which are stacked together, with the glass fibers in adjacent glass fiber / polypropylene layers having the same or different laying angles. For example, the glass fibers in multiple glass fiber / polypropylene layers can be laid at 0°, 45°, 90°, 90°, 45°, and 0°, with each layer having the same laying angle. Alternatively, the laying angles of the glass fibers in adjacent glass fiber / polypropylene layers can also be different. For instance, one layer of adjacent glass fiber / polypropylene layers may have glass fibers laid at 0°, 45°, 90°, 90°, 45°, and 0°, while another layer of adjacent glass fiber / polypropylene layers may have glass fibers laid symmetrically at other laying angles. This multi-layered, multi-angled symmetrical glass fiber laying design of the fiber-reinforced plastic layer 100 effectively avoids weak areas in the skin in a single direction, significantly improving the skin's crack resistance and fatigue resistance, thereby extending the service life of the composite structure.

[0033] In some embodiments, the fiber-reinforced plastic layer 100 is connected to the I-beam structure 200 via the steel structure layer 400. The fiber-reinforced plastic layer 100 is bonded to the steel structure layer 400. That is, the fiber-reinforced plastic layer 100 and the steel structure layer 400 can be bonded together using an adhesive. Exemplarily, the adhesive can be a structural adhesive such as epoxy resin, epoxy adhesive, polyurethane adhesive, or acrylic adhesive; for example, DP420 epoxy adhesive can be used. Bonded connections have advantages such as uniform stress distribution, good sealing performance, and no electrochemical corrosion.

[0034] Furthermore, the I-beam structural member 200 is bonded to the steel structural layer 400. That is, the I-beam structural member 200 and the steel structural layer 400 can also be bonded together using an adhesive, for example, by bonding the I-beam structural member 200 to the steel structural layer 400 with epoxy resin. This bonded connection effectively ensures the coordinated load-bearing performance between the core structural layer and the skin.

[0035] The I-beam structural member 200, after being connected to the skin, exhibits an I-shaped structure, which is the core component of the entire composite structure. The bending stress of the I-beam structure reaches its maximum at the location furthest from the neutral axis of the composite structure. The wide flanges of the I-beam structure, located at the upper and lower edges of the composite structure's cross-section, concentrate most of the material, enabling it to effectively resist tensile and compressive forces generated by bending. When subjected to lateral loads perpendicular to the axis of the I-beam structure, it exhibits extremely high bending strength and stiffness, allowing it to withstand large bending moments without failure and with minimal bending deformation. The I-beam structure perfectly matches the axial stiffness and bending resistance required in the aforementioned container side panels.

[0036] Based on the installation characteristics and usage environment of container side panels, they primarily require high axial stiffness along their axis to resist loads generated during loading, unloading, and transportation, and also need sufficient bending stiffness. According to these characteristics, a sandwich structure with I-beam structural members 200 is ideally suited for this type of application requiring high unidirectional mechanical performance, effectively meeting the load-bearing requirements of container side panels. The composite structure is a lightweight, high-strength composite material structure. Its core design concept is to achieve a combination of high-strength skin and core material structural layers through sandwich-like layering, significantly reducing weight while improving mechanical performance. The composite structure's panel consists of a steel structural layer 400, a fiber-reinforced plastic layer 100 (such as with carbon fiber or glass fiber), and the upper and lower flanges of the I-beam structural members 200, which bear the main bending stress and surface loads, providing compressive, tensile, and impact resistance. The core material of the composite structure is a lightweight, porous material structure composed of the web of the I-beam structural members 200 and a foamed structure 300, used to disperse shear stress and support the panel to prevent buckling. The core advantage of sandwich structures is their high specific strength / specific stiffness. Through the synergistic effect of the face panels and core materials, they achieve high load-bearing capacity and high bending resistance while maintaining lightweight construction. The key mechanical principle is that the face panels bear tensile / compressive loads; the core material resists shear deformation; and the overall performance is enhanced by increasing the cross-sectional height (core material thickness) to improve bending stiffness.

[0037] The following is combined with Figure 1 A method for preparing a container side panel composite structure provided in this disclosure will be described in detail.

[0038] The preparation method includes: S101. Prepare fiber-reinforced plastic layer 100 and steel structure layer 400 by stacking the fiber-reinforced plastic layer 100 and the steel structure layer 400. According to the layup design, after laying the glass fiber / polypropylene prepreg, place it in a hot press for hot pressing and curing.

[0039] Specifically, cut glass fiber / polypropylene prepreg and release cloth to appropriate sizes. Place the release cloth on the heated base plate of a hot press. Lay out the glass fiber / polypropylene prepreg layer by layer. Then, press the laid-out glass fiber / polypropylene prepreg and release cloth together using the hot press. The press head only needs to contact the glass fiber / polypropylene prepreg without applying pressure. Raise the hot press temperature from room temperature to approximately 190°C and maintain it for 30 minutes. After maintaining this temperature, allow it to cool to room temperature before demolding to obtain the glass fiber / polypropylene layer.

[0040] Optionally, the glass fibers in the glass fiber / polypropylene layer are symmetrically laid; there are multiple glass fiber / polypropylene layers, and multiple glass fiber / polypropylene layers are stacked, with the glass fibers in adjacent glass fiber / polypropylene layers laid at the same or different angles, in order to enhance the elastic modulus and stiffness of the glass fiber structure.

[0041] Specifically, after preparing the fiber-reinforced plastic layer 100 and the steel structure layer 400, the fiber-reinforced plastic layer 100 and the 0.35mm thick steel structure layer 400 can be bonded together with DP420 epoxy adhesive and cured under pressure for 7 hours to form a skin.

[0042] S102. Prepare multiple I-beam structural components 200 using wood. Specifically, wood with a high specific modulus can be selected to ensure good modulus even with lower mass; for example, Indonesian Merbau wood can be used, which has a high specific modulus and good corrosion resistance. Arrange the wood according to... Figure 4 The structural dimensions shown are machined into an I-beam structure of 200 using a table saw.

[0043] Alternatively, the choice of wood materials is quite flexible, and different types of wood with different properties can be selected according to different needs.

[0044] S103. Multiple I-beam structural members 200 are spaced apart, and one side of the multiple I-beam structural members 200 is connected to the steel structure layer 400.

[0045] Optionally, one side of the I-beam 200 is bonded to the steel structure layer 400 with epoxy resin and then cured under pressure for 7 hours.

[0046] S104. Fill the spaces between adjacent I-beam structural members 200 with foamed structure 300. Specifically, fill the spaces between adjacent I-beam structural members 200 with expanded polystyrene foam.

[0047] S105, the other side of multiple I-beam structural members 200 is connected to the steel structure layer 400.

[0048] Optionally, the other side of the I-beam 200 can be bonded to the steel structure layer 400 with epoxy resin and then cured under pressure for 7 hours.

[0049] The cured sample takes the shape of an I-beam. This structure is the core component of the entire plate structure. The I-beam design concentrates the material on the upper and lower flanges away from the neutral axis, while the web only bears the shear force, thereby maximizing the moment of inertia of the section, that is, the ability to resist bending deformation.

[0050] The composite structure provided in this disclosure has good mechanical properties and a low weight. For the same dimensions, this composite structure reduces weight by approximately 19% compared to corrugated steel. Regarding mechanical properties, a three-point bending test was conducted using a specimen with a length of 850 mm, a width of 50 mm, and a thickness of 40 mm (e.g., ...). Figure 7 As shown in the figure, the experimental results show that the central deflection of the composite structure is about 1 mm when subjected to a concentrated load of 180 N, about 2 mm when subjected to a concentrated load of 360 N, and about 3 mm when subjected to a concentrated load of 550 N, which can match the bending stiffness of corrugated steel well.

[0051] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0052] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include at least one of those features.

[0053] In the description of this disclosure, "multiple" means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.

[0054] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0055] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0056] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0057] Although embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A composite structure for container side panels, characterized in that, The composite structure includes: A core material structural layer, comprising a plurality of spaced-apart I-beam structural members and a foam structure located between adjacent I-beam structural members, wherein the I-beam structural members are made of wood; and The skin is disposed on the outside of the core material structural layer. The skin includes a fiber-reinforced plastic layer and a steel structure layer, and the fiber-reinforced plastic layer and the steel structure layer are stacked together.

2. The composite structure according to claim 1, characterized in that, The specific modulus of the wood material is greater than 15 GPa / (g / cm³). 3 ).

3. The composite structure according to claim 1, characterized in that, The foam structure is made of polystyrene.

4. The composite structure according to claim 1, characterized in that, The fiber-reinforced plastic layer is a glass fiber / polypropylene layer; The glass fibers in the glass fiber / polypropylene layer are symmetrically laid out.

5. The composite structure according to claim 4, characterized in that, The number of glass fiber / polypropylene layers is multiple, and the multiple glass fiber / polypropylene layers are stacked. The glass fibers in adjacent glass fiber / polypropylene layers may be laid at the same or different angles.

6. The composite structure according to claim 5, characterized in that, The fiber-reinforced plastic layer is connected to the I-beam structure through the steel structure layer.

7. The composite structure according to claim 6, characterized in that, The fiber-reinforced plastic layer is bonded to the steel structure layer.

8. The composite structure according to claim 6, characterized in that, The I-beam structure is bonded to the steel structure layer.

9. A method for preparing a composite structure for container side panels, characterized in that, The preparation method includes: Prepare a fiber-reinforced plastic layer and a steel structure layer, and stack the fiber-reinforced plastic layer and the steel structure layer together; Multiple I-beam structural components were fabricated using wood. Multiple I-beam structural members are spaced apart, and one side of each of the multiple I-beam structural members is connected to the steel structure layer; Fill the spaces between adjacent I-beam structural members with foam; and The other side of the plurality of I-beam structural members is connected to the steel structure layer.

10. The method for preparing the container side panel composite structure according to claim 9, characterized in that, The multiple I-beam structural members are connected to the steel structure layer by adhesive bonding.

Images