Composite buffer type pier anti-collision device and design method

Abstract

This application relates to the field of bridge engineering, and more particularly to a composite buffer-type bridge pier anti-collision device and its design method. The device includes an anti-collision main body surrounding the bridge pier and connecting and fixing components for fixing the anti-collision main body. The anti-collision main body includes an outer column assembly, an inner column assembly, and force-transmitting connectors. The outer column assembly consists of several outer columns connected by horizontal braces to form a closed loop structure, and the inner column assembly consists of several inner columns connected by horizontal braces to form a closed loop structure. Adjacent outer and inner columns are connected by force-transmitting connectors. The connecting and fixing components include column sleeves fixed to the bridge pier abutment, with the bottoms of the outer and inner columns detachably connected and fixed to the column sleeves. After being impacted by a vehicle, the horizontal displacement of the outer columns is transmitted to the inner columns through the force-transmitting connectors, causing the inner columns to deform. Both columns jointly bear the impact force of the vehicle, and the deformation of the members dissipates the impact energy, effectively protecting the safety of the main structure of the bridge pier.

Description

Technical Field

[0001] This application relates to the field of bridge engineering, and more specifically, to a composite buffer-type anti-collision device for bridge piers and its design method. Background Technology

[0002] With the rapid development of modern transportation, road traffic flow is continuously increasing, and road network density is constantly improving, leading to an increasingly complex vehicle operating environment. Against this backdrop, accidents involving vehicles losing control and colliding with bridge piers are frequent. Such accidents not only cause severe physical damage to the main bridge structure, reducing its overall load-bearing capacity and service life, but may even lead to catastrophic consequences such as bridge collapse. They also directly threaten the lives and property of vehicle occupants and surrounding people. Therefore, how to effectively improve the impact resistance of bridge piers and ensure the safe operation of transportation infrastructure has become a critical issue that urgently needs to be addressed in the field of bridge engineering.

[0003] Currently, the research and development of collision avoidance technology is gradually shifting from the traditional passive protection model towards intelligent monitoring and early warning, the application of high-performance new materials, and the integration of multiple disciplines. Although new collision avoidance technologies and concepts are emerging one after another, in practical engineering applications, considering factors such as construction costs, construction difficulty, and subsequent maintenance, traditional bridge pier collision avoidance facilities, with their mature technological accumulation, remain the mainstream choice for current engineering applications.

[0004] Currently, the traditional bridge pier collision protection facilities widely used in the engineering field mainly include steel guardrails, concrete crash barriers, and rubber fenders. These traditional facilities dominate primarily due to their simple structural design, relatively low material costs, and ease of construction. However, in terms of actual protective effect and structural response, traditional facilities still have significant limitations. In particular, their brittle fracture problem has always been a difficult point and a key research area restricting the improvement of protective performance. When subjected to high-energy vehicle impacts, steel guardrails are prone to severe deformation and tearing, and concrete crash barriers often undergo brittle fracture. This results in low energy absorption efficiency at the moment of impact, making it difficult to effectively buffer and dissipate the enormous impact kinetic energy, and failing to meet the demands of modern transportation for high-safety and high-reliability collision protection facilities. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a composite buffer-type bridge pier anti-collision device and its design method, in order to solve the problem of how to ensure the safety of the main structure of the bridge pier under the impact of a car collision.

[0006] In a first aspect, this application provides a composite buffer-type bridge pier anti-collision device, including an anti-collision body arranged around the bridge pier and a connecting and fixing component for fixing the anti-collision body; The anti-collision body includes an outer column assembly, an inner column assembly, and a force-transmitting connector; the outer column assembly is formed by connecting several outer columns through horizontal bracing to form a closed loop structure, and the inner column assembly is formed by connecting several inner columns through horizontal bracing to form a closed loop structure; adjacent outer columns and inner columns are connected by force-transmitting connectors. The connection and fixing assembly includes a column sleeve fixed to the pier foundation, and the bottoms of the outer column and the inner column are detachably connected and fixed to the column sleeve.

[0007] In one possible implementation, the connecting and fixing assembly further includes a tie rod, a washer, and a fastening nut. The bottom of the outer column, the bottom of the inner column, and the column sleeve are all provided with pre-drilled holes. The tie rod passes through the pre-drilled holes and is locked by the washer and the fastening nut.

[0008] In one possible implementation, a steel pad is welded to the bottom of the column sleeve, and the steel pad is pre-fixed to the foundation by anchoring steel bars.

[0009] In one possible implementation, the force-transmitting connector is an arc-shaped plate structure.

[0010] In one possible implementation, the outer column, inner column, and cross brace are all hollow tubular structures.

[0011] Secondly, this application provides a design method for a composite buffer-type bridge pier anti-collision device as described in any of the first aspects, comprising: During the construction phase of the bridge pier foundation, pre-embed connection and fixing components; The bottoms of the outer and inner columns are respectively connected and fixed to the column sleeves by the connecting and fixing components. The cross braces between the outer columns and between the inner columns, as well as the force-transmitting connectors connecting adjacent outer and inner columns, are installed in sequence to form a double-layered, composite, closed anti-collision body; wherein, the material specifications and structural dimensions of the outer columns, inner columns, cross braces, and force-transmitting connectors are determined based on preset impact load parameters.

[0012] In one possible implementation, during the pier cap construction phase, pre-embedded connection and fixing components are included, including: After the pile foundation construction is completed, the pile cap reinforcement is tied, the column sleeve is welded to the steel plate and then positioned and installed by anchoring reinforcement, and the pile cap concrete is poured.

[0013] In one possible implementation, after the installed anti-collision body is impacted, the method further includes: loosening the fastening nut, disassembling the tie rod, replacing the deformed component, and reinstalling it to restore the anti-collision body to its normal working state.

[0014] Compared with the prior art, the technical solution provided in this application has the following beneficial effects: The anti-collision device provided in this application mainly includes outer columns, inner columns, cross braces, arc-shaped plates, and column sleeves. The outer columns are connected to form a closed loop by the cross braces, and the inner columns are also connected to form a closed loop by the cross braces. The arc-shaped plates connect to adjacent outer and inner columns at both ends, forming a double-layer composite structure. After the anti-collision device is impacted by a vehicle, the outer columns first undergo horizontal displacement deformation. At this time, the arc-shaped plates transmit the horizontal displacement to the inner columns, causing the inner columns to deform. Both share the impact force of the vehicle. Because the horizontal displacement deformation of each outer and inner column is inconsistent, the cross braces and arc-shaped plates undergo tensile, compressive, and bending deformations. All members of the composite buffer-type bridge pier anti-collision facility participate in the work, dissipating impact energy through the deformation of the members, effectively protecting the safety of the main structure of the bridge pier. During maintenance, the deformed members are replaced, and the anti-collision facility can be restored to normal working condition.

[0015] The aforementioned composite buffer-type bridge pier anti-collision device is suitable for various regular and irregular bridge piers. It is practical and reliable, with low cost and maintenance. It is also recoverable and easy to repair, and has certain value for promotion and application. Attached Figure Description

[0016] Figure 1 This is a structural schematic diagram of a composite buffer-type bridge pier anti-collision device provided in Embodiment 1 of this application.

[0017] Figure 2 This is a top view of a composite buffer-type bridge pier anti-collision device provided in Embodiment 1 of this application.

[0018] Figure 3 This is a schematic diagram of the fixed connection between the outer / inner column and the connecting and fixing component provided in Embodiment 1 of this application.

[0019] Figure 4 This is an exploded view of the tie rod provided in Embodiment 1 of this application.

[0020] Figure 5 This is a flowchart illustrating the design method of a composite buffer-type bridge pier anti-collision device provided in Embodiment 2 of this application.

[0021] Figure 6 This is a schematic diagram of the composite buffer-type bridge pier anti-collision device and the load loading finite element model provided in Embodiment 3 of this application.

[0022] Figure 7 Stress cloud diagram (unit: MPa) of the anti-collision device under the fully elastic state of the bar during the first impact of the car provided in Embodiment 3 of this application.

[0023] Figure 8The stress cloud diagram (unit: MPa) of the anti-collision facility provided in Embodiment 3 of this application shows that after a car collision, the stress value of some members in the anti-collision facility exceeds its design value and enters a plastic state. The stress cloud diagram of the anti-collision facility considering the reduction of member stiffness in the plastic state is shown.

[0024] Figure 9 The diagram shows the horizontal deformation of the anti-collision facility (unit: mm) under plastic deformation after a car collision, resulting in a reduction in the stiffness of the members.

[0025] Explanation of reference numerals in the attached drawings: 1. Pier; 2. Abutment; 3. Pile foundation; 4. Outer column; 5. Inner column; 6. Cross brace; 7. Force transmission connector; 8. Column sleeve; 9. Fastening nut; 10. Tie rod; 11. Washer; 12. Steel pad; 13. Anchoring reinforcement. Detailed Implementation

[0026] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0027] Example 1 See Figure 1 This is a structural schematic diagram of a composite buffer-type bridge pier anti-collision device provided in Embodiment 1 of this application. Specifically, it includes an anti-collision main body arranged around the bridge pier, and connecting and fixing components for fixing the anti-collision main body.

[0028] In this embodiment, the aforementioned anti-collision body is a double-layer composite steel structure, installed on top of the pier 1 abutment 2. Specifically, the anti-collision body includes an outer column assembly, an inner column assembly, and a force-transmitting connector 7.

[0029] like Figures 1-2 As shown, the aforementioned external column assembly includes several external columns 4. Adjacent external columns 4 are connected by cross braces 6 to form a closed loop structure.

[0030] The aforementioned inner column assembly, located inside the aforementioned outer column assembly, includes several inner columns 5. Adjacent inner columns 5 are connected by cross braces 6 to form a closed loop structure. Simultaneously, adjacent outer columns 4 and inner columns 5 are connected by force-transmitting connectors 7.

[0031] In some embodiments, the force-transmitting connector 7 adopts an arc-shaped plate structure. After the composite buffer-type pier anti-collision device provided in this application is impacted by a vehicle, the outer column 4 first undergoes horizontal displacement deformation. At this time, the arc-shaped plate is used to transmit the horizontal displacement to the inner column 5, causing the inner column 5 to deform, and both jointly bear the impact force of the vehicle. Because the horizontal displacement deformation of each outer column 4 and inner column 5 is inconsistent, the cross brace 6 and the arc-shaped plate undergo tensile, compressive, and bending deformations. All members of the composite buffer-type pier anti-collision device participate in the work, dissipating impact energy through the deformation of the members, effectively protecting the safety of the main structure of the pier 1.

[0032] like Figure 3 As shown, the aforementioned connecting and fixing assembly includes column sleeves 8 fixed to the pier 1 foundation 2. The bottoms of each of the outer columns 4 and inner columns 5 are detachably connected and fixed to the corresponding column sleeves 8. During maintenance, the deformed members can be removed and replaced, and the anti-collision device can be restored to normal working condition.

[0033] In some embodiments, the aforementioned connecting and fixing assembly further includes multiple sets of tie rods 10, washers 11, and fastening nuts 9. Pre-drilled holes are provided at the bottom of the outer column 4, the bottom of the inner column 5, and the column sleeve 8. For example... Figure 4 As shown, the tie rod 10 is inserted into the reserved hole and locked by the washer 11 and the fastening nut 9, so as to realize the detachable fixing of the outer column 4, the inner column 5 and the column sleeve 8.

[0034] Furthermore, each column sleeve 8 is also welded with a steel pad 12 at its bottom. After welding, the column sleeve 8 and the steel pad 12 are fixed to the top of the foundation 2 by anchoring steel bars 13.

[0035] Compared with the prior art, the technical solution provided in Embodiment 1 of this application has the following beneficial effects: The composite buffer-type bridge pier anti-collision device provided in this application adopts a double-layer composite structure with outer and inner columns closed by horizontal bracing and connected by an arc-shaped plate. The structural design is scientific, practical, and reliable. When an impact occurs, the outer column preferentially undergoes horizontal displacement deformation. The displacement and impact force are synchronously transmitted to the inner column through the arc-shaped plate, causing the outer column, inner column, horizontal bracing, and arc-shaped plate to jointly undergo tensile, compressive, and bending deformations. All members work together to fully dissipate the impact energy and effectively ensure the safety of the bridge pier.

[0036] Example 2 Embodiment 2 of this application provides a design method for a composite buffer-type bridge pier anti-collision device. For example... Figure 5 As shown, the above method specifically includes the following steps: Step 101: During the construction phase of pier 1 and foundation 2, pre-embed connection and fixing components.

[0037] Specifically, after the construction of pile foundation 3 is completed, the reinforcing bars of pile cap 2 are tied, the column sleeve 8 is welded to the steel pad 12 and then positioned and installed by anchoring reinforcing bars 13, and the concrete of pile cap 2 is poured.

[0038] Step 102: Connect and fix the bottoms of the outer column 4 and the inner column 5 to the column sleeve 8 respectively using the above-mentioned connecting and fixing components.

[0039] Step 103: Install the cross braces 6 between the outer columns 4 and between the inner columns 5 in sequence, as well as the force transmission connectors 7 connecting the adjacent outer columns 4 and inner columns 5, to form a double-layer composite closed anti-collision body.

[0040] The material specifications and structural dimensions of the aforementioned outer column 4, inner column 5, cross brace 6, and force transmission connector 7 are determined based on preset impact load parameters.

[0041] Specifically, the specifications of the outer column 4, inner column 5, cross brace 6, and curved plate are determined based on calculations. The principle is that after being impacted by a vehicle, the outer column 4 will undergo horizontal displacement deformation. At this time, the curved plate will transmit the horizontal displacement to the inner column 5, causing the inner column 5 to deform. Simultaneously, the cross brace 6 and the curved plate will undergo tensile, compressive, and bending deformations. However, the maximum horizontal deformation of any of the above members near the pier 1 will not exceed the net distance between them and the pier 1. The vehicle impact energy is completely absorbed and dissipated by the composite buffer-type pier 1 anti-collision facility, effectively protecting the safety of the main pier structure.

[0042] Example 3 Embodiment 3 of this application provides a specific application scenario and design method for a composite buffer-type bridge pier anti-collision device. Taking a certain city overpass as an example, before pouring the pile foundation 3 and the pier cap 2, the column sleeve 8 and steel pad 12 are accurately positioned and welded together, and then fixed to the top of the pier cap 2 by anchoring steel bars 13. The concrete of the pier cap 2 and the bridge pier 1 are then poured.

[0043] The cross-sectional dimension of pier 1 is 150cm in diameter. The clear distance between the cross brace 6 and pier 1 is 180mm. The cross brace 6 and the curved plate are made of 160*60mm rectangular hollow steel pipes with a wall thickness of 10mm. The outer column 4 and inner column 5 are made of 250mm outer diameter circular hollow steel pipes with a wall thickness of 12mm. The steel material selected is Q235. A finite element model of the anti-collision facilities and load loading is established, such as... Figure 6 As shown.

[0044] According to current regulations, the impact force of a vehicle in the direction of travel is taken as 1000 kN. Under impact, the stress in some members of the composite buffer-type bridge pier anti-collision device exceeds the material's allowable value, entering a plastic state, such as... Figures 7-9As shown, after the member enters the plastic state, it undergoes significant plastic deformation. After equivalent reduction of the cross-sectional stiffness of the member in the plastic state, the maximum horizontal deformation near pier 1 is calculated to be 156 mm. The maximum horizontal deformation does not exceed the net distance of 180 mm between the member and pier 1, and the energy of the vehicle impact is completely absorbed and dissipated by the composite buffer-type pier anti-collision facility.

[0045] During maintenance, loosen the fastening nut 9, remove the tie rod 10, replace the deformed rod, and the anti-collision device can be restored to normal working condition.

[0046] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A composite buffer-type bridge pier anti-collision device, characterized in that, Includes an anti-collision body surrounding the bridge pier (1) and a connecting and fixing assembly for fixing the anti-collision body; The anti-collision body includes an outer column assembly, an inner column assembly, and a force transmission connector (7); the outer column assembly is formed by connecting several outer columns (4) through cross braces (6) to form a closed loop structure, and the inner column assembly is formed by connecting several inner columns (5) through cross braces (6) to form a closed loop structure. Adjacent outer columns (4) and inner columns (5) are connected by force transmission connectors (7). The connection and fixing assembly includes a column sleeve (8) fixed on the pier (1) and the foundation (2), and the bottom of the outer column (4) and the inner column (5) are respectively detachably connected and fixed to the column sleeve (8).

2. The composite buffer-type bridge pier anti-collision device according to claim 1, characterized in that, The connecting and fixing assembly also includes a tie rod (10), a washer (11) and a fastening nut (9). The bottom of the outer column (4), the bottom of the inner column (5) and the column sleeve (8) are all provided with reserved holes. The tie rod (10) passes through the reserved hole and is locked by the washer (11) and the fastening nut (9).

3. The composite buffer-type bridge pier anti-collision device according to claim 1, characterized in that, The bottom of the column sleeve (8) is also welded with a steel pad (12), which is pre-embedded and fixed in the foundation (2) by anchoring steel bars (13).

4. The composite buffer-type bridge pier anti-collision device according to claim 1, characterized in that, The force-transmitting connector (7) is an arc-shaped plate structure.

5. The composite buffer-type bridge pier anti-collision device according to claim 1, characterized in that, The outer column (4), inner column (5), and cross brace (6) are all hollow tubular structures.

6. A design method for a composite buffer-type bridge pier anti-collision device as described in any one of claims 1 to 5, characterized in that, include: During the construction phase of the bridge pier (1) and the foundation (2), pre-embed connection and fixing components; The bottoms of the outer column (4) and the inner column (5) are respectively connected and fixed to the column sleeve (8) by the connecting and fixing assembly; The cross bracing (6) between the outer columns (4) and between the inner columns (5) are installed in sequence, as well as the force-transmitting connector (7) connecting the adjacent outer columns (4) and inner columns (5) to form a double-layer composite closed anti-collision body; wherein, the material specifications and structural dimensions of the outer columns (4), inner columns (5), cross bracing (6) and force-transmitting connector (7) are determined based on the preset impact load parameters.

7. The design method of the composite buffer-type bridge pier anti-collision device according to claim 6, characterized in that, During the construction phase of the bridge pier (1) and the foundation (2), pre-embedded connection and fixing components are included, including: After the pile foundation (3) is completed, the reinforcing bars of the pile cap (2) are tied, the column sleeve (8) is welded to the steel pad (12) and then positioned and installed by anchoring the reinforcing bars (13), and the concrete of the pile cap (2) is poured.

8. The design method of the composite buffer-type bridge pier anti-collision device according to claim 6, characterized in that, When the installed anti-collision body is impacted, the method further includes: loosening the fastening nut (9), disassembling the tie rod (10), replacing the deformed component and reinstalling it to restore the anti-collision body to normal working condition.

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