Marine composite material laminated structure

Abstract

The invention relates to the technical field of framework assembling and machining, in particular to a marine composite material laminated structure which comprises an outer skin, and an inner skin is attached to the surface of one side of a damping layer. The composite material laminated structure for the ship is composed of the outer skin, the anti-stripping reinforcing layer, the sandwich layer, the damping layer and the inner skin, longitudinal bending, shearing and transverse rigidity improvement are achieved through the multi-direction reinforced outer skin, and the anti-stripping reinforcing layer forms resin anchoring points through a thermoplastic fiber thin net; the sandwich layer is designed through gradient partitions with different densities and thicknesses, so that a high-load area has higher compression resistance and bending resistance, a low-load area realizes light weight, the stress of the sandwich structure is effectively optimized, the longitudinal overall rigidity is improved, local crushing is prevented, and meanwhile, the strength of the sandwich structure is improved. A longitudinal drainage channel is arranged in the sandwich layer and corresponds to the inspection hole, so that drainage, ventilation and internal damage detection can be realized.

Description

Technical Field

[0001] This invention relates to the field of skeleton assembly and processing technology, and in particular to a marine composite material laminate structure. Background Technology

[0002] Marine composite laminate structures typically consist of an outer skin, a core layer, and an inner skin. By laminating fiber-reinforced materials with resin, a lightweight, high-strength hull structure with good corrosion resistance is formed. While commonly used glass fiber sandwich structures can achieve high specific stiffness and specific strength, existing marine composite laminate structures often suffer from limitations. Traditional core layers, with their uniform density and thickness, struggle to adapt to varying loads across different hull areas, leading to insufficient local stiffness or overall material waste. Furthermore, the interfaces between the outer skin and the core layer, and between the inner skin and the core layer, are prone to delamination under wave impact and fatigue loads, affecting structural lifespan. Existing sandwich structures generally lack effective internal damping layers, making it difficult to attenuate hull vibration and noise. Therefore, a new type of marine composite laminate structure is needed. Existing marine composite laminate structures have slow processing efficiency, cannot be drilled at the same workstation simultaneously, and are difficult to clean up, and are particularly prone to accumulating, which can easily damage the machine.

[0003] To address the aforementioned issues, a search revealed a patent with publication number CN118725596B that discloses a composite preparation process for enhancing the mechanical properties of marine laminated wood. The patent proposes "mixing wood powder, epoxy resin, antibacterial modified basalt fiber-titanium dioxide, stabilizer, and curing agent evenly, kneading in a two-roll mill, and hot-pressing in a hot press to obtain marine laminated wood. The antibacterial modified basalt fiber-titanium dioxide contains a large number of active groups, which can form a three-dimensional staggered support network in the matrix, producing a cross-linked network structure, effectively improving the mechanical properties of the matrix. Epoxy resin, as an adhesive, has strong bonding force and can tightly bond wood powder and other materials together, reducing wood brittleness." To reduce material waste and improve wood utilization to achieve environmental benefits, this invention produces laminated wood with stable structure and high strength. Through curing and cross-linking reaction, a network structure can be formed, further enhancing the overall mechanical strength of the laminated wood and extending its service life. The above-mentioned laminated wood, formed by curing wood powder and fiber-reinforced resin, has a homogeneous structure, lacks zoned load-bearing capacity, is easy to peel off at the interface, and does not have integrated functions of damping, drainage, and reinforcing ribs, making it difficult to meet the complex load requirements of ship hulls. This invention achieves higher bending stiffness, peel resistance, vibration reduction, and maintainability through the synergistic design of gradient core, anti-peeling reinforcement layer, damping layer, and longitudinal reinforcing ribs, significantly improving overall reliability.

[0004] In light of this, in-depth research into the aforementioned issues led to the creation of this case. Summary of the Invention

[0005] The purpose of this invention is to provide a marine composite laminate structure to solve the problems mentioned in the background art. In the use of existing marine composite laminate structures, the traditional sandwich layers are mostly of a single density and thickness, which are difficult to adapt to the load differences in different areas of the hull, resulting in insufficient local stiffness or overall material waste. The interfaces between the outer skin and the sandwich layer and the inner skin and the sandwich layer are prone to peeling under wave impact and fatigue loads, affecting the structural life. Existing sandwich structures generally lack effective internal damping layers, making it difficult to attenuate hull vibration and noise.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a marine composite laminate structure, comprising an outer skin, One side of the outer skin is fitted with an anti-peel reinforcement layer, one side surface of the anti-peel reinforcement layer is fitted with a core layer, one side surface of the core layer is fitted with a damping layer, and one side surface of the damping layer is fitted with an inner skin.

[0007] Preferably, the sandwich layer is provided with three groups, and each group has different density and thickness.

[0008] Preferably, the inner side of the sandwich layer is provided with a first sandwich region, a second sandwich region and a third sandwich region, wherein the density and thickness of the first sandwich region are greater than those of the second sandwich region, and the density and thickness of the second sandwich region are greater than those of the third sandwich region.

[0009] Preferably, the core layer is made of PVC foam, and the outer skin and inner skin are formed of glass fiber reinforced vinyl ester resin and glass fiber reinforced epoxy resin laminate.

[0010] Preferably, the layer above the anti-peel reinforcement layer is a thermoplastic fiber mesh with a density of 20-80 g / m².

[0011] Preferably, the damping layer is formed of rubber-modified resin or resin containing hollow microspheres, and the thickness of the damping layer is 0.2 to 2.0 mm.

[0012] Preferably, the inner skin has longitudinal reinforcing ribs along the length of the hull on its inner side, the longitudinal reinforcing ribs penetrate the core layer and connect with the outer skin, and a solid laminate is attached to the inner side of the inner skin, the longitudinal reinforcing ribs being attached to the solid laminate.

[0013] Preferably, the inner side of the sandwich layer is provided with a longitudinal drainage channel extending along the length of the hull, and one end of the longitudinal drainage channel is connected to a connector.

[0014] Preferably, an inspection hole is provided above the inner skin, and the longitudinal drainage channel corresponds to the position of the inspection hole.

[0015] Preferably, the outer skin and inner skin are laid in a multi-layer anti-peel reinforcement layer in the direction of 0° / ±45° / 90°, wherein the 0° direction is along the length of the hull, and the ±45° direction is used to bear in-plane shear loads.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. This marine composite laminate structure, through the multi-layered collaborative design of outer skin, anti-peel reinforcement layer, core layer, damping layer, and inner skin, enables the structure to have superior load-bearing capacity and durability when subjected to seawater pressure and wave impact. The outer skin is laid in 0° / ±45° / 90° directions, so that the 0° direction bears longitudinal bending and tensile and compressive forces, the ±45° direction resists in-plane shear and torsional loads, and the 90° direction improves lateral stiffness, thereby enhancing the overall stress performance of the outer side. The anti-peel reinforcement layer is formed by curing thermoplastic fiber mesh to form a rough interface and resin anchor points, producing an interlocking effect similar to micro-rivets, effectively improving the interfacial bonding strength between the outer skin and the core layer, and significantly inhibiting interfacial peeling and shear slip. The core layer has multiple groups of regions with different densities and thicknesses. Through gradient configuration, the high-load area has higher compressive and bending stiffness, while the medium and low-load areas achieve structural weight reduction, thereby achieving the effect of configuring materials as needed and improving the bending performance of the sandwich structure.

[0017] 2. This marine composite laminate structure features a damping layer on the inner side of the core layer, composed of rubber-modified resin or resin containing hollow microspheres. After curing, it can absorb and dissipate vibration energy at the microscale, effectively attenuating vibrations from wave impacts and ship operating equipment. This significantly reduces vibrations and noise transmitted to the inner skin and hull, improving structural comfort and delaying fatigue damage. The inner skin also employs a 0° / ±45° / 90° reinforced structure, serving as the main inner load-bearing layer to withstand tensile, compressive, and in-plane shear forces. Longitudinal reinforcing ribs are provided on its inner side, and a high-strength base is provided through a solid laminate, increasing the overall longitudinal stiffness of the hull and preventing the reinforcing ribs from directly impacting the core layer and causing crushing. The longitudinal drainage channels within the core layer, via joints, enable drainage, ventilation, and inspection functions. Internal water content and damage can be inspected through the correspondence with inspection holes, solving the maintenance difficulties of traditional sandwich structures and significantly improving the long-term service reliability and maintainability of the structure. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic cross-sectional view of the main body of the present invention; Figure 3 This is a top view schematic diagram of the sandwich partition structure of the present invention; Figure 4This is a schematic diagram illustrating the layered structure of the anti-peeling reinforcement layer between the outer skin and the core of the present invention. Figure 5 This is a schematic diagram illustrating the layered structure of the core, damping layer, and inner skin of the present invention. Figure 6 This is a schematic diagram of the layered structure of the longitudinal stiffeners of the present invention; Figure 7 This is a schematic diagram of the drainage and inspection channel structure of the present invention; Figure 8 For the present invention Figure 7 Enlarged diagram of point A in the middle.

[0019] In the figure: 1. Outer skin; 2. Anti-peel reinforcement layer; 3. Sandwich layer; 4. First sandwich area; 5. Second sandwich area; 6. Third sandwich area; 7. Damping layer; 8. Inner skin; 9. Longitudinal reinforcing rib; 10. Solid laminate; 11. Longitudinal drainage channel; 12. Joint; 13. Inspection hole. Detailed Implementation

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

[0021] Please see Figure 1-8 This invention provides a technical solution: a marine composite laminate structure, including an outer skin 1. One side of the outer skin 1 is bonded with an anti-peel reinforcement layer 2, one side of the anti-peel reinforcement layer 2 is bonded with a core layer 3, one side of the core layer 3 is bonded with a damping layer 7, and one side of the damping layer 7 is bonded with an inner skin 8. Through the setting of the outer skin 1, it serves as the main load-bearing layer on the outer side of the hull structure. It adopts a glass fiber reinforced resin laminate laid in the 0° / ±45° / 90° direction. The 0° direction provides core longitudinal bending and tensile and compressive stiffness along the length of the hull, the ±45° direction bears in-plane shear and torsional loads, and the 90° direction enhances lateral stability, resisting seawater pressure and wave impact in all directions.

[0022] Furthermore, the core layer 3 is divided into three sections, each with different densities and thicknesses. Through the core layer 3, PVC foam material is used to form the core support layer of the sandwich structure. By utilizing the material's good compressive and shear properties and large cross-sectional height, the structural bending stiffness is significantly improved. The external load is converted into shear stress in the foam core and tensile and compressive stress between the inner skin 8 and the outer skin 1, thus achieving efficient force transfer.

[0023] Furthermore, the inner side of the sandwich layer 3 is provided with a first sandwich region 4, a second sandwich region 5 and a third sandwich region 6. The density and thickness of the first sandwich region 4 are greater than those of the second sandwich region 5, and the density and thickness of the second sandwich region 5 are greater than those of the third sandwich region 6. By setting the first sandwich region 4 as a high-rigidity load-bearing area of ​​the sandwich layer 3, its greater density and thickness design can provide excellent local bending stiffness and compressive strength, accurately matching the stress requirements of high-load areas such as the midship and deck of the ship.

[0024] Furthermore, the core layer 3 is made of PVC foam, and the outer skin 1 and inner skin 8 are formed by glass fiber reinforced vinyl ester resin and glass fiber reinforced epoxy resin laminate. Through the setting of the inner skin 8, it serves as the inner main load-bearing layer. It adopts a 0° / ±45° / 90° multi-layer reinforcement structure symmetrical with the outer skin 1, and together they form a double load-bearing surface of the sandwich structure to bear the inner tensile and compressive loads and in-plane shear loads, thus balancing the structural stress.

[0025] Furthermore, above the anti-peel reinforcement layer 2 is a thermoplastic fiber mesh with a density of 20-80 g / m². By setting the anti-peel reinforcement layer 2, a thermoplastic fiber mesh with a density of 20-80 g / m² is laid between the outer skin 1 and the core layer 3. After the resin is cured, a rough interface and resin anchor points are formed, constructing a micro-riveting structure, which greatly increases the interface contact area and mechanical interlocking force.

[0026] Furthermore, the damping layer 7 is formed of rubber-modified resin or resin containing hollow microspheres, and the thickness of the damping layer 7 is 0.2 to 2.0 mm. By setting the damping layer 7, which is made of rubber-modified resin or resin containing hollow microspheres with a thickness of 0.2 to 2.0 mm, it serves as a bonding transition layer between the core layer 3 and the inner skin 8, ensuring a strong interlayer connection. At the same time, relying on the microscopic deformation and energy dissipation characteristics of the rubber phase or hollow microspheres, it absorbs and attenuates external vibration and impact energy, reduces the vibration and noise level transmitted to the inside of the hull, improves cabin comfort, delays structural fatigue damage, and enhances the operational stability of the hull in complex sea conditions.

[0027] Furthermore, longitudinal stiffeners 9 are provided on the inner side of the inner skin 8 along the length of the hull. The longitudinal stiffeners 9 penetrate the core layer 3 and connect with the outer skin 1. A solid laminate 10 is attached to the inner side of the inner skin 8. The longitudinal stiffeners 9 are attached to the solid laminate 10. By setting the longitudinal stiffeners 9, which penetrate the core layer 3 along the length of the hull and connect the inner skin 8 and the outer skin 1, the longitudinal bending moment is transformed from being borne by a single shell plate to being borne by the shell plate and the longitudinal stiffeners 9 working together. This significantly improves the overall longitudinal stiffness and buckling resistance of the hull. The longitudinal stiffeners 9 are attached to the solid laminate 10 on the inner side of the inner skin 8 to form a high-strength root base, avoiding the stiffeners from directly acting on the core layer 3 and causing local crushing or peeling. At the same time, it disperses the concentrated load transmitted by the longitudinal stiffeners 9, further optimizing the structural stress distribution and enhancing the hull's resistance to wind, waves and heavy loads.

[0028] Furthermore, a longitudinal drainage channel 11 is provided on the inner side of the core layer 3 along the length of the hull. One end of the longitudinal drainage channel 11 is connected to a connector 12. By setting the longitudinal drainage channel 11, which is opened on the inner side of the core layer 3 along the length of the hull and connected to the connector 12 at one end, internal water can be drained, ventilation and detection devices can be connected, solving the problem that water accumulation inside the core structure can easily lead to corrosion and strength reduction. The channel corresponds to the inspection hole 13 of the inner skin 8, providing maintenance personnel with a channel for internal condition observation and damage detection, making it easy to detect and deal with potential hazards such as water content and damage in the core layer 3 in a timely manner, and improving the convenience and safety of structural maintenance.

[0029] Furthermore, an inspection hole 13 is provided on the upper part of the inner skin 8, and the longitudinal drainage channel 11 corresponds to the position of the inspection hole 13. By setting the inspection hole 13 to precisely correspond to the position of the longitudinal drainage channel 11, a visual inspection and maintenance access is provided for the interior of the sandwich structure. Maintenance personnel can directly observe the interior of the channel and the local condition of the sandwich layer 3 through the inspection hole 13, or insert a detection probe for non-destructive testing. This design solves the internal monitoring problem caused by the sealing of the sandwich structure, making it easier to detect hidden dangers such as water accumulation, corrosion, and interlayer peeling in a timely manner, shortening the maintenance cycle, reducing maintenance costs, and ensuring the long-term reliable operation of the hull structure.

[0030] Furthermore, the outer skin 1 and the inner skin 8 are laid with a multi-layer anti-peeling reinforcement layer 2 in the direction of 0° / ±45° / 90°, wherein the 0° direction is along the length of the hull, and the ±45° direction is used to bear in-plane shear loads.

[0031] Working principle: When the outer surface of the hull is subjected to seawater pressure or wave impact loads, the outer skin 1 first bears the in-plane tensile, compressive, and bending stresses on the outer side. The outer skin 1 employs a multi-layered reinforcing structure laid in the 0° / ±45° / 90° directions. This allows the 0° direction to provide the main longitudinal bending and tensile / compressive stiffness along the hull's length. Then, the fibers in the ±45° direction bear the in-plane shear and torsional loads, while the 90° direction enhances lateral stiffness and stability. The outer skin 1 transfers the load as in-plane stress to the peel-resistant reinforcing layer 2, which is closely attached to its inner side. Above the peel-resistant reinforcing layer 2 is a surface density of... A thermoplastic fiber mesh of 20–80 g / m² forms a rough interface and resin anchor points after resin curing, which is equivalent to setting a micro-riveting structure between the outer skin 1 and the core layer 3. This increases the interface contact area and mechanical interlocking force. Under repeated wave loads and bending deformation, it effectively inhibits interface peeling and shear slip between the outer skin 1 and the core layer 3, thereby significantly improving the shear strength and fatigue life of the interface. The load is further transferred from the anti-peeling reinforcement layer 2 to the core layer 3. The core layer 3 as a whole acts as a web and support layer, and its interior is set with The structure consists of three sections: a first sandwich region 4, a second sandwich region 5, and a third sandwich region 6, each differing in density and thickness. The first sandwich region 4 has a higher density and thickness than the second sandwich region 5, and the second sandwich region 5 has a higher density and thickness than the third sandwich region 6. This gradient design allows the first sandwich region 4, located near the midships or high-load areas, to provide higher local bending stiffness and compressive strength. The second sandwich region 5 supports the load in medium-load areas, while the third sandwich region 6, with its lower density and thickness, is used in the edge or low-load areas, thus meeting overall stiffness and strength requirements. Under the premise of reducing material usage and structural weight, mechanical optimization of material configuration is achieved. Since the core layer 3 is made of PVC foam, it has good compressive and shear resistance. It forms a large cross-sectional height between the outer skin 1 and the inner skin 8, which improves the bending stiffness of the whole plate. The external load is converted into shear stress in the foam core and tensile and compressive stress in the inner skin 8 and the outer skin 1, realizing the force mechanism of a typical sandwich structure. The inner side of the core layer 3 is tightly attached to the damping layer 7, which is formed by rubber-modified resin or resin containing hollow microspheres, and has a thickness of 0.2 to 2.The inner skin 8, with a diameter of 0mm, serves as a bonding transition layer between the core layer 3 and the inner skin 8. Furthermore, it absorbs and attenuates external vibrations and impacts through the deformation and energy dissipation of the rubber phase or hollow microspheres at the microscale, reducing the vibration and noise levels transmitted to the inner skin 8 and the hull. This improves comfort and delays structural fatigue damage. The inner skin 8 also features a multi-layered reinforcing structure laid in the 0° / ±45° / 90° direction, bearing the tensile and compressive forces and in-plane shear forces on the inner side during overall stress. It is another main load-bearing layer in the sandwich structure, opposite to the outer skin 1. To improve the longitudinal strength and local compressive resistance of the hull, longitudinal reinforcing ribs 9 are provided along the length of the hull on the inner side of the inner skin 8. These ribs penetrate the core layer 3 and connect to the outer skin 1, so that the longitudinal bending moment is no longer borne solely by the shell plate, but jointly by the shell plate and the longitudinal reinforcing ribs 9, thereby improving the overall strength. For longitudinal stiffness, a solid laminate 10 is bonded to the inner side of the inner skin 8, and longitudinal reinforcing ribs 9 are bonded to the solid laminate 10. This is equivalent to setting a high-strength solid base at the root of the longitudinal reinforcing ribs 9, avoiding direct action of the longitudinal reinforcing ribs 9 on the core layer 3, reducing the risk of local crushing and peeling. To solve problems such as water accumulation and difficulty in inspection inside the sandwich structure, a longitudinal drainage channel 11 is extended along the length of the hull on the inner side of the core layer 3. One end of the longitudinal drainage channel 11 is connected to a connector 12, which allows for drainage, ventilation, or connection of testing devices from the outside or inside the cabin. Inspection holes 13 are also provided above the inner skin 8, corresponding to the longitudinal drainage channel 11. This allows maintenance personnel to observe and inspect the interior of the longitudinal drainage channel 11 and the local condition of the core layer 3 through the inspection holes 13, or insert testing probes to monitor and maintain the water content and damage inside the sandwich structure.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A marine composite laminate structure, comprising an outer skin (1), characterized in that: One side of the outer skin (1) is attached to an anti-peel reinforcement layer (2), one side of the anti-peel reinforcement layer (2) is attached to a core layer (3), one side of the core layer (3) is attached to a damping layer (7), and one side of the damping layer (7) is attached to an inner skin (8).

2. The marine composite laminate structure according to claim 1, characterized in that: The sandwich layer (3) is divided into three zones, and each zone has a different density and thickness.

3. The marine composite laminate structure according to claim 1, characterized in that: The inner side of the sandwich layer (3) is provided with a first sandwich region (4), a second sandwich region (5) and a third sandwich region (6). The density and thickness of the first sandwich region (4) are greater than those of the second sandwich region (5), and the density and thickness of the second sandwich region (5) are greater than those of the third sandwich region (6).

4. A marine composite laminate structure according to claim 1, characterized in that: The core layer (3) is made of PVC foam, and the outer skin (1) and inner skin (8) are formed of glass fiber reinforced vinyl ester resin and glass fiber reinforced epoxy resin laminate.

5. A marine composite laminate structure according to claim 1, characterized in that: Above the anti-peel reinforcement layer (2) is a thermoplastic fiber mesh with a density of 20-80 g / m².

6. A marine composite laminate structure according to claim 1, characterized in that: The damping layer (7) is formed of rubber-modified resin or resin containing hollow microspheres, and the thickness of the damping layer (7) is 0.2 to 2.0 mm.

7. A marine composite laminate structure according to claim 1, characterized in that: The inner skin (8) has longitudinal reinforcing ribs (9) arranged along the length of the hull. The longitudinal reinforcing ribs (9) penetrate the core layer (3) and are connected to the outer skin (1). The inner skin (8) has a solid laminate (10) attached to its inner side. The longitudinal reinforcing ribs (9) are attached to the solid laminate (10).

8. A marine composite laminate structure according to claim 1, characterized in that: The inner side of the sandwich layer (3) extends along the length of the hull and has a longitudinal drainage channel (11), one end of which is connected to a connector (12).

9. A marine composite laminate structure according to claim 1, characterized in that: An inspection hole (13) is provided above the inner skin (8), and the longitudinal drainage channel (11) is located opposite to the inspection hole (13).

10. A marine composite laminate structure according to claim 1, characterized in that: The outer skin (1) and inner skin (8) are laid in a multi-layer anti-peeling reinforcement layer (2) in the direction of 0° / ±45° / 90°, wherein the 0° direction is along the length of the hull, and the ±45° direction is used to bear in-plane shear loads.

Images