A full composite emergency bridge and a manufacturing method thereof

Abstract

The application discloses a full-composite emergency bridge, which comprises a ribbed main beam, a slope cover plate and a stress transmission key, wherein the ribbed main beam, the slope cover plate and the stress transmission key are all made of composite materials; the ribbed main beam is a simply supported beam provided with a plurality of webs, i.e. a plurality of ribs, and the two ends of the ribbed main beam are oblique sections, forming an isosceles trapezoidal structure; one slope cover plate is assembled on each oblique section, and the slope surface and the plane are connected through the stress transmission key, i.e. the upper panel of the ribbed main beam and the slope cover plate are connected through the stress transmission key. The emergency bridge has the advantages of light self weight, convenient transportation and erection, increased rapid maneuverability and improved operation efficiency. The emergency bridge has good designability, can adapt to severe working environments, has strong corrosion resistance and good economic performance. In addition, the composite material can improve the protection and concealment of equipment and materials to a certain extent.

Description

Technical Field

[0001] This invention belongs to the field of emergency equipment technology, specifically an all-composite material emergency bridge. Background Technology

[0002] Material selection plays a crucial role in the research and production of emergency bridge equipment. Structural design can only proceed smoothly based on the selection of suitable materials. In recent years, choosing appropriate materials has been a long-term goal for emergency bridge equipment researchers worldwide. The structural materials widely used in modern emergency bridge equipment are mainly steel and aluminum alloys. Steel has advantages such as high strength, good plasticity and toughness, uniform stress distribution, high reliability, high elastic modulus, strong adaptability to dynamic loads, and mature design calculation theory. However, it is heavy, has poor mobility, poor corrosion resistance, and high maintenance costs. In particular, its heavy weight causes a series of problems, such as the need for multiple transport vehicles and high tonnage vehicles, resulting in poor mobility, limited ability to overcome and cross obstacles, and high labor intensity during operation. Aluminum alloys have advantages such as high strength, light weight, and resistance to corrosion, greatly improving the reduction of equipment weight and increasing mobility. However, they are expensive, have lower stiffness than steel, and the weldability of aluminum needs further improvement. Summary of the Invention

[0003] The purpose of this invention is to address the problems existing in the prior art by providing an all-composite material emergency bridge and its manufacturing method.

[0004] The technical solution to achieve the purpose of this invention is as follows: On the one hand, an all-composite material emergency bridge is provided. The bridge includes a ribbed main beam, a slope cover plate, and stress transfer keys. The ribbed main beam, the slope cover plate, and the stress transfer keys are all made of composite materials. The ribbed main beam is a simply supported beam with several webs, i.e., several ribs, and its two ends are inclined sections, forming an isosceles trapezoidal structure. Each inclined section is covered with a slope cover plate, and the slope and the plane are connected by stress transfer keys. That is, the upper panel of the ribbed main beam and the slope cover plate are connected by stress transfer keys.

[0005] Furthermore, the lower surface of the slope cover plate is provided with several ribs, which are installed in conjunction with the ribs on the inclined section of the closely ribbed main beam.

[0006] Furthermore, the number of ribs on the inclined section of the closely ribbed main beam is twice the number of ribs on the slope cover plate, and each rib on the slope cover plate is engaged between two ribs on the inclined section of the closely ribbed main beam.

[0007] Furthermore, longitudinal FRP prepreg is bonded at the bridge piers and at the cross-section of the bridge, with the fiber direction consistent with the bridge length direction.

[0008] Furthermore, the entire bridge is bonded with circumferential FRP prepreg, with the fiber direction aligned with the direction perpendicular to the bridge length.

[0009] Furthermore, the ribbed main beam and the slope cover plate are bonded together with adhesive.

[0010] Furthermore, the ribs are arranged along the length of the bridge.

[0011] On the other hand, a method for manufacturing an all-composite material emergency bridge is provided, the method comprising:

[0012] The cross-sectional dimensions of the ribbed main beam and the slope cover plate are designed according to the bridge's design load-bearing capacity.

[0013] Based on the bending moment envelope of the simply supported beam, design the starting position of the variable cross section and the slope inclination angle α.

[0014] Based on the dimensions of the above design, the oblique sections of the ribbed main beam and the slope cover plate are cut;

[0015] For the side of the ribbed main beam where the upper panel and the slope cover plate are in contact, cut the upper panel and the slope cover plate to a certain length d respectively;

[0016] The part of the ribbed main beam where the upper panel and the slope cover plate meet, i.e. the protruding part of the web of the ribbed main beam at the bend, is corrected to a flat surface.

[0017] Based on the dimensions of the cut and modified portions described above, stress transfer keys of the same size are machined using composite material sheets;

[0018] Apply composite material adhesive to each rib of the slope cover plate and insert it into the closely ribbed main beam;

[0019] Apply composite material-specific adhesive to both sides of the stress transfer key and insert it between the panels of the ribbed main beam and the slope cover plate.

[0020] Longitudinal FRP prepreg is bonded at the bridge foot and at the cross-section, with the fiber direction consistent with the bridge length direction;

[0021] The entire bridge is bonded with circumferential FRP prepreg, with the fiber direction aligned with the direction perpendicular to the bridge length. After curing at room temperature, the all-composite bridge body is complete.

[0022] Furthermore, the upper panel and the slope cover plate of the ribbed main beam have the same thickness, and the length d is equal to twice the thickness of the upper panel or the slope cover plate.

[0023] Compared with the prior art, the significant advantages of this invention are:

[0024] (1) The all-composite material emergency bridge of the present invention is manufactured using existing mature composite material processing technology and has many advantages that steel structures cannot match: light weight, corrosion resistance, good overall stability, and good safety. Moreover, the structural damping of composite materials is much greater than that of steel, so it can also reduce the vibration of the bridge when equipment passes over it, thereby improving the smoothness, comfort and safety of vehicles traveling on the bridge.

[0025] (2) The all-composite material emergency bridge adopts a box structure, which will significantly reduce the overall weight compared to the truss structure and improve the overall performance of the bridge.

[0026] (3) The main advantages of all-composite material emergency bridges are their high specific strength, which allows for a reduction in the self-weight of the bridge while ensuring load-bearing capacity. This makes transportation and erection easier, thus improving mobility and erection speed. Therefore, traditional erection methods can be changed, and drones or helicopters can be used for airdrop erection (e.g., Figure 6 As shown in the image, this increases rapid mobility and improves operational efficiency. If two bridges need to be erected within a certain area, traditional emergency bridges require two sets of equipment. However, with the all-composite material emergency bridge method, which allows for direct airdrop and erection via drones or helicopters, only one set of equipment can be used, enabling sequential erection and significantly improving turnaround efficiency.

[0027] (4) All-composite emergency bridges offer excellent designability, allowing for optimized design by selecting components and structural types according to structural stress requirements, thus meeting the stringent requirements of military equipment. Furthermore, the widespread use of computers and structured general-purpose programs allows for engineering design to be implemented at a more microscopic level. Wartime emergency bridge equipment operates under frequent and complex conditions, and is susceptible to damage from explosions. Composite materials can absorb a certain amount of impact energy, exhibiting high shock absorption and fatigue strength. Another significant advantage is corrosion resistance, enabling them to adapt to harsh working environments and perform excellently in chemical engineering and permanent underground (underwater) projects. The use of composite materials in military bridge equipment significantly enhances corrosion resistance, simplifies maintenance, extends service life, and provides good economic performance throughout its lifespan. In addition, composite materials can, to a certain extent, improve the protection and concealment capabilities of equipment.

[0028] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of an all-composite material emergency bridge in one embodiment, wherein... Figure 1 (a) in the diagram is a structural diagram of an all-composite emergency bridge. Figure 1 (b) in the diagram is an assembly drawing of an emergency bridge made entirely of composite materials.

[0030] Figure 2This is a schematic diagram of a closely ribbed main beam in one embodiment, wherein... Figure 2 (a) in the figure is a cross-sectional view of the ribbed main beam. Figure 2 (b) is a side view of the closely ribbed main beam.

[0031] Figure 3 This is a schematic diagram of a slope cover plate in one embodiment, wherein Figure 3 (a) in the diagram is a cross-sectional view of the slope cover plate. Figure 3 (b) is a side view of the slope cover plate.

[0032] Figure 4 This is a schematic diagram of the connection between the ribbed main beam and the slope cover plate in one embodiment, wherein... Figure 4 (a) in the figure is a cross-sectional view of the connection between the ribbed main beam and the slope cover plate. Figure 4 (b) is a side view of the connection between the ribbed main beam and the slope cover plate.

[0033] Figure 5 This is a schematic diagram of the prepreg fiber cloth laying in one embodiment, wherein... Figure 5 (a) shows a schematic diagram of longitudinal FRP prepreg being bonded at the bridge abutment and at the variable cross-section. Figure 5 (b) is a schematic diagram of the circumferential FRP prepreg bonded to the entire bridge.

[0034] Figure 6 This is a schematic diagram of the installation method in one embodiment. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0036] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0037] In one embodiment, combined Figure 1 This invention provides an all-composite material emergency bridge, comprising a ribbed main girder 1, a slope cover plate 2, and a stress transfer key 3. All components—the ribbed main girder 1, the slope cover plate 2, and the stress transfer key 3—are made of composite materials. The ribbed main girder 1 is a simply supported beam with several webs (ribs) and inclined sections at both ends, forming an isosceles trapezoidal structure. Figure 2As shown, each inclined section is covered with a slope cover plate 2, and the slope and the plane are connected by stress transfer key 3, that is, the upper panel of the ribbed main beam 1 is connected to the slope cover plate by stress transfer key 3.

[0038] Here, the ribbed main girder 1 is the primary load-bearing structure. Due to the high flexibility of the composite material, a web is added to increase its stiffness, resulting in a ribbed design. To further reduce the bridge weight, based on the bending mechanism of a simply supported beam, the bending moment is smaller near the ends of the beam; therefore, a variable cross-section can be used. The ends of the ribbed beam are made into inclined sections, and the design slope α must be calculated based on the load-bearing capacity.

[0039] Preferably, the ribs are arranged along the length of the bridge.

[0040] Here, at the point of contact between the slope and the plane, to avoid stress and hinder stress transfer, the upper panel of the ribbed main beam 1 and the panel of the slope cover plate 2 are each cut back by a length d, and the ribs of the ribbed main beam 1 at this point are flattened. Based on these dimensions, stress transfer keys 3 are machined from sheet metal. Since the upper panel is under compression when the beam is bent, stress transfer keys 3 make stress transfer clearer and simpler, and also avoid stress concentration.

[0041] Furthermore, in one embodiment, such as Figure 3 As shown, the lower surface of the slope cover plate 2 is provided with several ribs, which are installed in conjunction with the ribs on the inclined section of the closely ribbed main beam 1.

[0042] Preferably, the number of ribs on the inclined section of the closely ribbed main beam is twice the number of ribs on the slope cover plate, and each rib on the slope cover plate is engaged between two ribs on the inclined section of the closely ribbed main beam.

[0043] Here, the ribbed main beam 1 and the slope cover plate 2 are bonded with a special adhesive for composite materials (this is not limited to adhesive bonding). Adhesive is applied to each rib of the slope cover plate 2, and then... Figure 4 (a) shows the insertion of the closely ribbed main beam 1.

[0044] Furthermore, in one embodiment, longitudinal FRP prepreg is bonded at the bridge piers and at the variable cross-section areas, with the fiber direction aligned with the bridge's length direction, such as... Figure 5 As shown in (a), local enhancement is achieved.

[0045] The entire bridge is bonded with circumferential FRP prepreg, with the fiber direction aligned with the direction perpendicular to the bridge length. Figure 5 As shown in (b), the connection between the ribbed main beam 1, the slope cover plate 2, and the stress transfer key 3 can be further strengthened. Secondly, a restraint ring ply can be added to the beam to significantly improve its load-bearing capacity.

[0046] This is not limited to the aforementioned methods of strengthening fixation.

[0047] The following describes a method for fabricating an all-composite material emergency bridge, the method comprising:

[0048] 1. Design the cross-sectional dimensions of the ribbed main beam and the slope cover plate according to the bridge's design load-bearing capacity. The cross-sectional shape is as follows: Figure 2 , Figure 3 As shown, the number of webs is not limited to the number shown in the figure and can be designed according to needs. However, the number of webs of the closely ribbed main beam 1 should be twice the number of webs of the slope cover plate 2 to facilitate the assembly of the two.

[0049] 2. Based on the bending moment envelope of the simply supported beam, design the starting position of the variable cross-section and the slope inclination angle α.

[0050] 3. Based on the dimensions designed above, cut the oblique sections of the ribbed main beam and the slope cover plate.

[0051] 4. Based on the thickness of the upper panel of the ribbed main beam 1 and the slope cover plate 2, cut a certain length d (the thickness of two panels) of panel back from each panel (e.g., Figure 4 (b)) At the same time, the protruding part of the web of the closely ribbed main beam 1 at the bend is corrected to a plane. According to Figure 4 (b) shows the dimensions of the stress transfer key 3, which is fabricated using composite material sheet.

[0052] 5. Apply special adhesive to each rib of the slope cover plate 2, and then follow the instructions. Figure 4 (a) The ribbed main beam 1 is inserted as shown in the diagram. Special adhesive is also applied to both sides of the stress transfer key 3 and inserted between the ribbed main beam 1 and the panel of the slope cover plate 2.

[0053] 6. Apply longitudinal FRP prepreg at the bridge abutments and at areas with varying cross-sections, ensuring the fiber direction aligns with the bridge's length (e.g., ...). Figure 5 (a)). Finally, the entire bridge is bonded with circumferential FRP prepreg, with the fiber direction aligned with the direction perpendicular to the bridge length (e.g., ...). Figure 5 (b) Attach the composite material to the bridge from one end to the other, ensuring that the overlap length of the two circumferential attachments meets the design requirements and that the entire bridge body is covered. After curing at room temperature, the all-composite bridge body is complete.

[0054] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention without departing from its spirit and scope should be included within the protection scope of the present invention.

Claims

1. An all-composite material emergency bridge, characterized in that, The bridge includes a ribbed main beam, a slope cover plate, and stress transfer keys. The ribbed main beam, slope cover plate, and stress transfer keys are all made of composite materials. The ribbed main beam is a simply supported beam with several webs, i.e., several ribs, and its two ends are inclined sections, forming an isosceles trapezoidal structure. Each inclined section is covered with a slope cover plate, and the slope and the plane are connected by stress transfer keys. That is, the upper panel of the ribbed main beam and the slope cover plate are connected by stress transfer keys. The method for manufacturing the all-composite material emergency bridge specifically includes: The cross-sectional dimensions of the ribbed main beam and the slope cover plate are designed according to the bridge's design load-bearing capacity. Based on the bending moment envelope of the simply supported beam, design the starting position of the variable cross section and the slope inclination angle α. Based on the dimensions of the above design, the oblique sections of the ribbed main beam and the slope cover plate are cut; For the side of the ribbed main beam where the upper panel and the slope cover plate are in contact, cut the upper panel and the slope cover plate to a certain length d respectively; The part of the ribbed main beam where the upper panel and the slope cover plate meet, i.e. the protruding part of the web of the ribbed main beam at the bend, is corrected to a flat surface. Based on the dimensions of the cut and modified portions described above, stress transfer keys of the same size are machined using composite material sheets; Apply composite material adhesive to each rib of the slope cover plate and insert it into the closely ribbed main beam; Apply composite material-specific adhesive to both sides of the stress transfer key and insert it between the panels of the ribbed main beam and the slope cover plate. Longitudinal FRP prepreg is bonded at the bridge foot and at the cross-section, with the fiber direction consistent with the bridge length direction; The entire bridge is bonded with circumferential FRP prepreg, with the fiber direction aligned with the direction perpendicular to the bridge length. After curing at room temperature, the all-composite bridge body is complete.

2. The all-composite material emergency bridge according to claim 1, characterized in that, The lower surface of the slope cover plate is provided with several ribs, which are installed in conjunction with the ribs on the inclined section of the closely ribbed main beam.

3. The all-composite material emergency bridge according to claim 1, characterized in that, The number of ribs on the inclined section of the closely ribbed main beam is twice the number of ribs on the slope cover plate, and each rib on the slope cover plate is engaged between two ribs on the inclined section of the closely ribbed main beam.

4. The all-composite material emergency bridge according to claim 1, characterized in that, The bridge footings and cross-sections are all covered with longitudinal FRP prepreg, with the fiber direction aligned with the bridge length.

5. The all-composite material emergency bridge according to claim 1, characterized in that, The entire bridge is bonded with circumferential FRP prepreg, with the fiber direction aligned with the direction perpendicular to the bridge length.

6. The all-composite material emergency bridge according to claim 1, characterized in that, The ribbed main beam and the slope cover plate are also bonded together with adhesive.

7. The all-composite material emergency bridge according to claim 1, characterized in that, The ribs are arranged along the length of the bridge.

8. The all-composite material emergency bridge according to claim 1, characterized in that, The upper panel and the slope cover plate of the ribbed main beam have the same thickness, and the length d is equal to twice the thickness of the upper panel or the slope cover plate.

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