Novel bridge pier negative Poisson's ratio rockfall impact prevention structure device

Abstract

The invention discloses a novel bridge pier attachment type negative Poisson's ratio rockfall impact prevention structure device which is formed by splicing and assembling different independent units, the installation position and layout of an anti-collision device can be reasonably selected according to the section form and height of a bridge pier and the surrounding environment, and the protection effect of the anti-collision device is improved to the maximum extent. The internal structure of the device relates to a special negative Poisson's ratio structural form, every two adjacent core layer unit cells are mutually connected and arranged in a staggered mode, porous units arranged at intervals are formed in space, under the action of falling stone impact force, negative Poisson's ratio materials can be subjected to compression deformation, gaps in the materials can be extruded and filled through the compression deformation, and therefore the negative Poisson's ratio materials are formed. The negative Poisson's ratio structure unit cells are more tightly engaged with each other to form a stable connection state, the internal structure of the material is more complex, the material density is increased, the falling stone impact effect is difficult to further expand inwards, and the damage of falling stone impact to the pier structure is remarkably reduced.

Description

Technical Field

[0001] The present invention relates to the field of road and bridge collision prevention, and in particular to a bridge pier anti-falling rock impact device with a novel negative Poisson's ratio structure. Background Art

[0002] During their service life, bridge piers in mountainous areas may be subjected to impact loads from falling rocks, which can have a corresponding impact. The impact loads are short-lived and high-intensity, causing significant damage to the pier structure. One current approach to bridge collision prevention is to add collision prevention structures to the outside of the piers, using the strength and toughness of the reinforcement materials themselves to replace the piers in withstanding the impact of falling rocks. When traditional materials are subjected to impact loads, they are compressed by the impact force and flow from the impact site to the surrounding areas in a direction perpendicular to the impact, which can easily cause local fractures. However, when subjected to impact loads, negative Poisson's ratio materials are compressed in the direction of the impact and shrink laterally. The material will flow near the impact site, "aggregating" at the impact site. This phenomenon will increase the local density of the material, effectively resisting high-speed impact loads. At the same time, negative Poisson's ratio materials usually adopt a cellular structure, which is lightweight and high-strength. These properties can be used to make protective devices with good impact resistance.

[0003] A negative Poisson's ratio bridge pier crash barrier is a composite material shell filled with a negative Poisson's ratio structural energy-absorbing core. Its primary purpose is to cushion and absorb energy when rockfall strikes a bridge pier, thereby reducing damage to the pier itself and protecting the integrity of the bridge. Summary of the Invention

[0004] In order to enhance the stability and impact resistance of the bridge pier structure, the present invention provides a bridge pier anti-collision device with a negative Poisson's ratio effect. This device involves a special negative Poisson's ratio structural design, so that under the impact of falling rocks, the internal microstructure of the device changes and the internal material density increases, effectively dispersing and absorbing the stress generated by the impact, thereby reducing damage to the bridge pier itself and the bridge structure.

[0005] The present invention adopts the following technical solutions:

[0006] A bridge pier rockfall protection device with a negative Poisson's ratio effect includes an anti-collision shell, a negative Poisson's ratio structural energy dissipation core, an inner steel plate, and some connecting components. The negative Poisson's ratio structural energy dissipation core is composed of adjacent star-shaped cells connected by structural support transverse ribs and structural support longitudinal ribs to form a three-dimensional mesh structure, and two adjacent core layer cells are interconnected to form porous units arranged at intervals. Under the impact of falling rocks, the star-shaped negative Poisson's ratio material will undergo compression deformation, causing the originally loose pore structure to gradually become tight. This compression deformation will cause the voids inside the material to be squeezed and filled, making the internal structure of the material more complex, thereby increasing the density of the material.

[0007] Furthermore, the bridge pier anti-falling rock impact device is composed of multiple modules, and the shapes include "I" shape and arc shape. The modules are connected into a whole through mortise and tenon structure, and reinforced by pins and attached to both sides of the bridge pier.

[0008] Furthermore, the modules are composed of a plurality of independent units, including an anti-collision shell, a negative Poisson's ratio structural energy dissipation core, an inner steel plate, and some connecting components.

[0009] Furthermore, the anti-collision shell is a composite steel sandwich. The outer surface of the anti-collision structure first bears the impact force and should be thicker than the inner steel plate.

[0010] Furthermore, the composite material steel interlayer is 30 mm thick and the inner steel layer is 10 mm thick.

[0011] Furthermore, the inner core of the negative Poisson's ratio structure includes three layers of core unit cells, and adjacent core layers are staggered to form a highly ordered and tightly connected structural network.

[0012] Furthermore, the core layer is composed of star-shaped cells arranged through structural support transverse ribs, and adjacent star-shaped cells are arranged at intervals to form a porous unit.

[0013] Furthermore, the side length of the star-shaped unit cell is 100 mm, and the steel pipes with a diameter of 20 mm at both ends are connected by bolts, with an outer convex angle of 30° and an inner concave angle of 120°.

[0014] Compared with existing bridge pier anti-rockfall impact measures, the present invention has the following beneficial effects:

[0015] The special structural form of the negative Poisson's ratio star-shaped unit cell spacing in the structural core of the present invention can not only effectively reduce the density of the material, but also exert a negative Poisson's ratio effect when subjected to external impact. That is, under the action of stress, the pore structure inside the material will be further compressed and deformed, absorbing and dispersing the impact energy. The various staggered units will be more tightly engaged with each other under the action of the impact load, forming a stable connection state, which is more difficult to further dent and reduce damage to the structure.

[0016] The device, comprised of multiple independent modules, facilitates the convenient and efficient disassembly, transportation, and installation of rockfall protection for mountain highway bridge piers, as well as easy repair and replacement after damage. Depending on the cross-sectional form of the pier, the device can be assembled into various configurations, including straight and curved shapes. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the negative Poisson's ratio structural device for protecting bridge piers from rockfall impact;

[0018] Figure 2Schematic diagram of the appearance of the bridge pier anti-rockfall impact structure device;

[0019] Figure 3 Top view of the bridge pier's rockfall impact protection structure;

[0020] Figure 4 Schematic diagram of the two-dimensional arrangement of negative Poisson's ratio structures;

[0021] Figure 5 Schematic diagram of the three-dimensional arrangement of negative Poisson's ratio structures;

[0022] Figure 6 Schematic diagram of the shock aggregation of negative Poisson's ratio structures;

[0023] Among them: 1-anti-collision shell, 1-1-outer steel plate, 1-2-fiber reinforced composite material, 2-star-shaped negative Poisson's ratio structure core, 3-inner steel plate, 4-connecting bolts. DETAILED DESCRIPTION

[0024] like Figure 1 As shown, the present invention provides a new type of attached bridge pier protection against falling rock impact negative Poisson's ratio structural device. In order to make the purpose and technical solution of the embodiment of the present invention clearer, the device structure of the embodiment of the present invention will be clearly and completely described below in combination with the specific structural drawings of the embodiment of the present invention.

[0025] The pier rockfall impact protection structure is composed of independent modules, such as Figure 2 As shown, the outer shapes include "I" shape and arc shape. Each independent unit is provided with a slot, which fits together with units of other forms to form an integral structure and is fixed in a latching manner through connecting bolts 4 to enhance the strength of the connection structure. The setting of the independent unit makes secondary disassembly and assembly easier and more convenient.

[0026] Each independent module, such as Figure 3 As shown, it includes an anti-collision shell 1, a star-shaped negative Poisson's ratio structural core 2, an inner steel plate 3, and connecting bolts 4.

[0027] The anti-collision shell 1 specifically refers to a composite steel splint, with an outer steel plate 1-1 as the shell and a fiber-reinforced composite material 1-2 as the core. When the bridge pier is hit by falling rocks, it first bears the impact force and consumes part of the energy.

[0028] The negative Poisson's ratio structure core 2 is the main energy-consuming part of the device and is designed as a star-shaped structure with a negative Poisson's ratio effect based on steel or composite materials, such as Figure 4 As shown, the star-shaped cells of each core layer are staggered to form more space. The core layers are arranged in an array every 8 cm along the height direction of the device to form a three-dimensional porous lattice structure, as shown in Figure 5 As shown, the inner core of the structure impacted by falling rocks is Figure 6As shown, they gather toward the extruded part, forming a "fitting" overall structure, making it difficult for the indentation to expand further inward.

[0029] The technical solutions provided by the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only intended to help understand the method and core concept of the present application. Those skilled in the art may modify and improve the present application, and such modifications and improvements are also included in the scope of protection of the claims of the present application.

Claims

1. A new type of bridge pier negative Poisson's ratio rockfall impact protection structure device, characterized by: The device consists of multiple independent modules with structural forms such as "I" and arc. Each independent unit is spliced ​​and connected into a whole through mortise and tenon structure, and reinforced with pins and attached to both sides of the pier.

2. The novel bridge pier negative Poisson's ratio rockfall impact protection structure device according to claim 1 is characterized in that: The module is 1 meter high and is assembled, spliced ​​and stacked by multiple individual modules to achieve the design of pier-attached anti-falling rock impact structural devices with different cross-sectional forms and heights.

3. The novel bridge pier negative Poisson's ratio rockfall impact protection structure device according to claim 1 is characterized in that: It includes an anti-collision shell 1, a negative Poisson's ratio structural energy dissipation core 2, an inner steel plate 3, and some connecting components. The negative Poisson's ratio structural energy dissipation core 2 is located in the cavity between the anti-collision shell 1 and the inner steel plate 3, and is fitted together with them to form numerous concave porous spaces.

4. The novel bridge pier negative Poisson's ratio rockfall impact protection structure device according to claim 1 is characterized in that: The anti-collision shell 1 is a fiber-reinforced composite steel splint, which is first subjected to the impact of falling rocks and has a thickness greater than that of the inner steel plate.

5. The novel bridge pier negative Poisson's ratio rockfall impact protection structure device according to claim 1 is characterized in that: The negative Poisson's ratio structure energy dissipation inner core 2 is a star-shaped negative Poisson's ratio structure with three core layers arranged in space. The unit cells of each core layer are staggered with the adjacent layers.

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