Steel structure bridge construction device without post-maintenance

Abstract

The utility model provides a kind of steel structure bridge maintenance-free construction device in later period, including steel structure bridge box girder, the upper portion of steel structure bridge box girder is paved with steel structure bridge deck paving, the outside of steel structure bridge box girder is provided with steel sheet mesh, the surface of steel sheet mesh uses high ductility concrete finish, replaces traditional protective coating, insulates external corrosive medium, avoid steel structure from being damaged due to corrosion, wear and tear etc., to reduce maintenance requirement;Box girder longitudinal rib plate, the inner wall of steel structure bridge box girder is welded in the box girder longitudinal rib plate, for ensuring the stability of steel structure bridge box girder itself.The utility model, set up steel structure bridge box girder, structural adhesive, steel sheet mesh and the composite protective structure of high ductility concrete finish, replace traditional single protective coating, can strengthen the durability of structure, maintenance-free, substantially reduce the maintenance cost of steel structure protective coating in later period.

Description

Technical Field

[0001] This utility model relates to the field of bridge post-maintenance technology, specifically a post-maintenance-free structural device for steel structure bridges. Background Technology

[0002] Steel-structure bridges are a type of bridge that uses steel as its primary load-bearing component and are an important branch of bridge engineering. Their core advantage stems from the high strength and good ductility of steel, which can meet the engineering requirements of large spans and complex structures. Modern steel-structure bridges generally adopt prefabricated structures, achieving rapid assembly through standardized components to adapt to different span scenarios.

[0003] Compared with conventional concrete structures, steel bridges have inherent disadvantages in terms of durability and post-maintenance costs. The integrity of the protective coating directly affects the durability of the steel structure. Post-maintenance requires measures such as regular inspection, anti-corrosion treatment, and structural repair to ensure safety. Specifically, the following key aspects are included: (1) Using strain, displacement, vibration and other sensors to monitor the bridge status in real time, establishing a data acquisition and analysis platform, and setting early warning indicators to detect early defects. Regular inspections should focus on key parts such as welds, joints, and supports to form dynamic management files; (2) Regularly cleaning the bridge surface and checking the drainage system, grinding and removing rust from rusted parts and repainting them with anti-rust paint, assessing the wear of the coating annually and repairing it in a timely manner. Using anti-corrosion coatings or external steel reinforcement can delay structural aging; (3) Repairing cracks with precise technology and resetting expansion joints, replacing damaged guardrails or supports, and replacing components in severe cases. The load-bearing capacity is increased by increasing the cross-section and pasting carbon fiber cloth to ensure structural stability; (4) A routine inspection mechanism is established, and an annual inspection of all bridges in the district is carried out every year. Intelligent monitoring technology (such as dehumidification system) is used to improve management efficiency. Strict quality control and safety management are required during the maintenance process to reduce the impact on traffic.

[0004] In summary, the maintenance cost of steel structure bridges is relatively high. Their durability depends on the integrity of the protective coating. Safety needs to be ensured through multiple steps, including sensor monitoring, regular cleaning and rust removal, coating repair, crack repair, and routine inspections. The process is complicated and costly. At the same time, traditional protective coatings are susceptible to aging and peeling due to environmental factors, which further increases the frequency and investment of maintenance. Utility Model Content

[0005] The purpose of this utility model is to provide a steel structure bridge maintenance-free construction device to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: A maintenance-free structural device for steel bridges, comprising: The steel structure bridge box girder has a steel structure bridge deck paved on top and a steel mesh installed on the outer side. The surface of the steel mesh is finished with high-ductility concrete, which replaces the traditional protective coating to isolate it from external corrosive media and prevent the steel structure from being damaged by rust, wear, etc., thereby reducing maintenance requirements. By replacing the traditional protective coating with high-ductility concrete, the risk of damage to the steel structure is reduced from the root, and the frequency of later maintenance is reduced. The longitudinal ribs of the box girder are welded to the inner wall of the steel structure bridge box girder to ensure the stability of the steel structure bridge box girder itself, improve the overall rigidity, and ensure the load-bearing safety of the bridge during long-term use.

[0007] Preferably, the high-ductility concrete finish uses concrete with a strength grade of C30 to C40, the thickness of the high-ductility concrete finish is 15 to 20 mm, and the surface of the high-ductility concrete finish is polished to a smooth and flat state, with a natural concrete color.

[0008] Preferably, the high-ductility concrete finish serves as a permanent protective layer for the steel structure bridge box girder, enhancing its durability. This permanent protective layer design replaces traditional easily worn coatings, extending the service life of the steel structure and achieving the goal of long-term maintenance-free operation.

[0009] Preferably, the left, right, and bottom surfaces of the steel structure bridge box girder are all made of structurally bonded steel mesh. The steel mesh is used to enhance the connection reliability between the steel structure bridge box girder and the high-ductility concrete finish, and to enhance the crack resistance of the high-ductility concrete finish, thereby ensuring the stability of the protective structure.

[0010] Preferably, the structural adhesive is evenly spread between the steel mesh and the steel structure bridge box girder to prevent the steel mesh from falling off the sides and bottom of the steel structure bridge box girder, and to ensure that the steel mesh is firmly bonded to the steel structure.

[0011] Preferably, the steel structure bridge box girder is provided with box girder transverse diaphragms at equal intervals to divide the steel structure bridge box girder into multiple areas to ensure the stability of the steel structure bridge box girder itself.

[0012] Preferably, the inspection manhole on the box girder diaphragm is provided on the box girder diaphragm for maintenance personnel to pass through during later maintenance, taking into account both maintenance-free requirements and maintenance convenience.

[0013] Preferably, the cement, aggregates, mineral powder and other raw materials used in the high-ductility concrete finish are from the same batch, and the quality, dosage and construction process of the fibers in the high-ductility concrete finish are strictly controlled to ensure that there are no obvious cracks after construction, improve the integrity and durability of the protective layer, and extend the maintenance-free period.

[0014] Compared with the prior art, the beneficial effects of this utility model are: This utility model proposes a composite protective structure consisting of a steel bridge box girder, structural adhesive, steel mesh, and high-ductility concrete finish, which replaces the traditional single protective coating. This structure enhances the durability of the structure, eliminates the need for maintenance, and significantly reduces the maintenance costs of the steel structure protective coating in the later stages.

[0015] This invention utilizes a steel mesh formed by stamping thin steel plates. The mesh openings connect with structural adhesive and high-ductility concrete, enhancing the adhesion between the steel mesh and the steel structure. This also improves the crack resistance of the concrete finish, preventing the steel mesh from detaching and the concrete finish from cracking, thus ensuring the integrity of the protective layer.

[0016] This invention, by setting a high-ductility concrete finish with a strength grade of C30 to C40 and a thickness of 15 to 20 mm, not only has sufficient strength to resist external erosion, but also avoids the problem of brittle cracking caused by excessive strength, thus achieving a balance between protective effect and economy, and ensuring the isolation effect of corrosive media.

[0017] This utility model, by setting at least 20 longitudinal ribs in the area divided by the transverse diaphragm of each box girder, forms a crisscrossing three-dimensional support system, which resists lateral forces laterally, strengthens axial load in the longitudinal direction, refines the structural stress and avoids stress concentration, comprehensively improves the structural rigidity and deformation resistance of the steel structure bridge box girder, and ensures long-term load-bearing safety.

[0018] This utility model provides a reinforced inspection manhole on each box girder diaphragm, with the edges reinforced by ribs or thickened steel plates. The opening size is adapted to the entry and exit of maintenance personnel and tools, which not only meets the full range of maintenance needs, but also avoids stress concentration and collapse risks caused by the opening, thus balancing the goal of maintenance-free operation with maintenance convenience. Attached Figure Description

[0019] Fig. 1 This is a schematic diagram of the overall structure of this utility model; Fig. 2 This is a schematic diagram of the installation of the longitudinal ribs of the box girder of this utility model.

[0020] In the diagram: 1. Steel structure bridge box girder; 2. Steel mesh; 3. High-ductility concrete finish; 4. Steel structure bridge deck pavement; 5. Box girder diaphragm; 6. Inspection manhole on the box girder diaphragm; 7. Longitudinal ribs of the box girder. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example

[0022] Please see Figs. 1-2 This utility model provides a technical solution: A maintenance-free structural device for steel bridges includes a steel bridge box girder 1, on which a conventional steel bridge deck pavement 4 is laid to meet the load-bearing requirements of the bridge deck; while the left side, right side and bottom side of the steel bridge box girder 1 form key protection areas, and long-term protection is achieved through a composite structure of "steel bridge box girder 1-structural adhesive-steel mesh 2-high ductility concrete finish 3".

[0023] On the outside of the steel structure bridge box girder 1, steel mesh 2 is first bonded with structural adhesive that is evenly spread. The structural adhesive can ensure a firm bond between steel mesh 2 and steel structure and effectively prevent steel mesh 2 from falling off. Then, a high-ductility concrete finish 3 is laid on the surface of steel mesh 2 to replace the traditional easily damaged protective coating.

[0024] In this embodiment, the high-ductility concrete finish 3 uses concrete with a strength grade of C30 to C40 and a thickness strictly controlled between 15 and 20 mm. It has sufficient structural strength to resist external wear and can also isolate corrosive media such as moisture and oxygen through physical barriers, thereby reducing the risk of damage to the steel structure due to rust and wear from the source and reducing the frequency of later maintenance.

[0025] For high-ductility concrete cladding, C30 to C40 strength concrete is preferred, which can be flexibly adjusted according to actual construction needs. Concrete in this strength range has sufficient compressive strength and durability to resist external impact, wear and natural environmental erosion, while avoiding the problem of easy cracking due to increased brittleness caused by excessive strength. It achieves long-term protection and has an appearance similar to a plain exposed concrete bridge, with good visual effect. The thickness of 15 to 20 mm achieves a balance between protective effect and economy. Too thin and it is difficult to form an effective physical barrier, while too thick and it will increase the self-weight of the structure and increase material costs. This thickness can ensure the isolation effect against corrosive media such as moisture and oxygen, reducing the risk of steel structure corrosion from the root.

[0026] The composite protective structure of "steel bridge box girder 1 - structural adhesive - steel mesh 2 - high-ductility concrete finish 3" has significant advantages over traditional single protective coatings: traditional coatings are prone to aging and peeling due to ultraviolet radiation, rain erosion, and temperature changes, requiring regular rust removal and recoating, resulting in high maintenance costs; while this device forms a permanent protective layer through a multi-layer composite structure. The combination of steel mesh 2 and structural adhesive solves the problem of reliable connection between the concrete finish and the steel structure, and the crack resistance and durability of high-ductility concrete ensure long-term stable protective effect, greatly reducing the frequency of later maintenance and lowering labor and material input costs.

[0027] It should be noted that the steel mesh 2 is made of thin steel plate by stamping. Its mesh structure has a uniform pore distribution, which allows it to form a connection effect similar to "mechanical interlocking" when combined with structural adhesive and high-ductility concrete finish 3. The structural adhesive can penetrate and cure through the pores, enhancing the adhesion between the steel mesh 2 and the steel structure bridge box girder 1, and preventing the steel mesh 2 from falling off locally due to external vibration or long-term use. At the same time, the high-ductility concrete finish 3 can fill the pores of the steel mesh 2 during pouring, so that the concrete finish and the steel mesh 2 form an integral load-bearing structure, significantly improving the crack resistance of the concrete finish and preventing it from cracking and falling off under conditions such as temperature changes and structural deformation, thus ensuring the integrity of the protective layer.

[0028] The addition of steel mesh 2 not only strengthens the connection reliability between the steel structure bridge box girder 1 and the high-ductility concrete veneer 3, but also enhances the crack resistance of the concrete veneer, further ensuring the stability of the protective structure.

[0029] To enhance the internal structural stability of the steel bridge box girder 1, at least 20 longitudinal ribs 7 are installed inside the steel bridge box girder 1 and fixed to the inner wall of the steel bridge box girder 1. At least 8 longitudinal ribs 7 are installed on the inner sides of the top and bottom surfaces of the steel bridge box girder 1, and at least 2 longitudinal ribs 7 are installed on the inner sides of the left and right surfaces. These longitudinal ribs provide longitudinal support for the overall structure, ensuring the stability of the steel bridge box girder 1 and improving its overall stiffness, thus guaranteeing the load-bearing safety of the bridge during long-term use. At the same time, the box girder transverse diaphragms 5, which are evenly distributed inside the steel bridge box girder 1, divide the steel bridge box girder 1 into multiple independent areas. Through transverse support, the structural deformation resistance is further enhanced. Working in synergy with the longitudinal ribs, the structural stability of the steel bridge box girder 1 is comprehensively improved.

[0030] It should be noted that the number of transverse diaphragms 5 of the box girder is flexibly selected based on the bridge length and stress requirements, and they are arranged at equal intervals along the length of the steel structure bridge box girder 1, with a common spacing between 2 and 4 meters, to ensure the uniformity of the transverse division and the strength of the support. Each independent area divided by the box girder transverse diaphragms 5 is provided with at least 20 box girder longitudinal ribs 7. The box girder longitudinal ribs 7 are evenly distributed on the inner wall of the steel structure bridge box girder 1 in the area. The dense and orderly longitudinal support further refines the structural stress and avoids deformation problems caused by local stress concentration. The longitudinal ribs and transverse diaphragms form a crisscrossing three-dimensional support system. Laterally, the transverse diaphragms resist lateral forces, and longitudinally, the dense ribs in the area strengthen the axial bearing capacity. The two work together to comprehensively improve the structural rigidity and deformation resistance of the steel structure bridge box girder 1 from a spatial dimension, providing a solid guarantee for the long-term safe bearing of the bridge.

[0031] like Fig. 2 The longitudinal ribs 7 of the box girder adopt a "U"-shaped channel structure design, with a symmetrical arc-shaped bend in cross-section. The opening faces the inner wall of the steel structure bridge box girder 1 and is welded and fixed to the inner wall. The straight bottom section forms the longitudinal load-bearing surface. The top and bottom edges of the ribs are rounded to avoid stress concentration at sharp angles. The thickness of the ribs varies depending on the stress level of the area, generally between 8 and 12 mm, and can be appropriately thickened to 15 mm in critical stress areas. The length of each longitudinal rib 7 is adapted to the length of its independent area, and both ends are welded to the adjacent box girder transverse diaphragms 5. After grinding, the high-ductility concrete finish 3 has a smooth and flat surface, resembling the natural color of concrete. While providing protection, it also ensures structural aesthetics, resembling a plain, exposed concrete bridge. To ensure the durability of the protective effect, the cement, aggregates, and mineral powder used in the high-ductility concrete finish 3 are all from the same batch. Furthermore, the quality, dosage, and construction process of the fibers are strictly controlled to effectively prevent obvious cracks after construction, improve the integrity and durability of the protective layer, and extend the maintenance-free period.

[0032] In this embodiment, the high-ductility concrete finish 3 requires strict control over the use of cement, aggregates, mineral powder, and other raw materials from the same batch, ensuring the materials are as uniform as possible. Strict control over the quality, dosage, and construction process of the fibers is also crucial. Mixed batches of raw materials may lead to cracking due to inconsistencies in material shrinkage rates, heat of hydration, and other characteristics. Using materials from a single batch ensures uniform concrete texture, thereby reducing the risk of cracking from the source and laying the foundation for the integrity of the protective layer. The quality of fibers in high-ductility concrete directly affects its crack resistance and toughness; high-quality fibers can effectively inhibit the generation and propagation of micro-cracks. Precise control of fiber dosage balances the workability and mechanical properties of the concrete. Insufficient dosage fails to provide crack resistance, while excessive dosage may lead to uneven concrete mixing and increased construction difficulty. By strictly controlling fiber parameters, the crack resistance of the concrete finish can be significantly enhanced, preventing the impact on the durability of the steel structure due to the penetration of water, oxygen, and other corrosive media through cracks. Furthermore, it reduces potential defects such as honeycomb, pitting, and hollow areas, which directly weaken the insulating effect of the protective layer. Strict process control ensures a tight bond between the cladding, steel mesh, and steel structure, forming a continuous and complete physical barrier that effectively isolates the steel structure from external corrosive media.

[0033] In addition, a manhole 6 for inspection is reserved on the box girder diaphragm 5, providing a convenient passage for necessary inspection and maintenance operations in the future, achieving the goal of long-term maintenance-free operation while taking into account the convenience of maintenance.

[0034] It should be noted that each box girder diaphragm 5 has a corresponding inspection manhole 6, ensuring that maintenance personnel can enter different sections of the steel structure bridge box girder 1 through any diaphragm area, meeting the needs of full-range maintenance. The edges of the inspection manholes 6 on the box girder diaphragms are reinforced with reinforcing ribs or thickened steel plates, which effectively avoids stress concentration around the manholes by increasing local structural strength, preventing collapse or deformation during long-term use. At the same time, the opening size of the manholes is precisely designed, with both width and height meeting the needs of adult maintenance personnel to carry conventional tools and enter and exit smoothly, ensuring personnel safety and ease of operation during maintenance, and further improving the feasibility of later maintenance.

[0035] like Fig. 1As shown, the maintenance manhole 6 on the box girder diaphragm adopts a rectangular opening design, forming a regular rectangular structure. The long side is arranged along the height direction of the steel structure bridge box girder 1, and the short side corresponds to the thickness direction of the diaphragm. The edge of the opening is formed by welding a closed reinforcing rib to form a frame. The reinforcing rib is made of "L"-shaped angle steel or rectangular steel pipe, which is fully welded to the main steel plate of the diaphragm to form a rigid reinforcing ring around the manhole, compensating for the weakening of the overall integrity of the diaphragm by the opening. Triangular reinforcing plates are set at the four corners of the inner side of the manhole. The plates are welded to the diaphragm and the reinforcing rib respectively to further disperse the corner stress and avoid cracks caused by stress concentration at the right angles of the rectangular opening. The opening size is usually designed to be 800-1000mm wide and 1800-2000mm high, which not only meets the needs of adult maintenance personnel to enter and exit upright, but also balances the convenience of passage and structural safety through a reasonable length-to-width ratio, ensuring that the maintenance passage is provided without affecting the lateral support function of the diaphragm.

[0036] All other parts of this utility model not described herein are the same as existing technologies, or are known technologies, or can be implemented using existing technologies, and will not be described in detail here.

[0037] Although embodiments of the present 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 present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A maintenance-free structural device for steel bridges, characterized in that, include: A steel structure bridge box girder (1) is covered with a steel structure bridge deck pavement (4) on top of the steel structure bridge box girder (1). A steel mesh (2) is provided on the outside of the steel structure bridge box girder (1). The surface of the steel mesh (2) is covered with a high-ductility concrete finish (3) to replace the traditional protective coating and to isolate external corrosive media. Longitudinal ribs (7) of the box girder are provided on the inner wall of the steel structure bridge box girder (1) to ensure the stability of the steel structure bridge box girder (1).

2. The maintenance-free structural device for steel bridges according to claim 1, characterized in that: The high-ductility concrete finish (3) uses concrete with a strength grade of C30 to C40, and the thickness of the high-ductility concrete finish (3) is 15 to 20 mm.

3. The maintenance-free structural device for steel bridges according to claim 2, characterized in that: The high-ductility concrete finish (3) serves as a permanent protective layer for the steel structure bridge box girder (1) to enhance its durability.

4. The maintenance-free structural device for steel bridges according to claim 1, characterized in that: The left, right and bottom surfaces of the steel structure bridge box girder (1) are all made of structural adhesive steel mesh (2).

5. A maintenance-free structural device for steel bridges according to claim 4, characterized in that: The structural adhesive is evenly spread between the steel mesh (2) and the steel structure bridge box girder (1).

6. The maintenance-free structural device for steel bridges according to claim 1, characterized in that: The steel structure bridge box girder (1) is provided with box girder transverse diaphragms (5) at equal intervals, which divide the steel structure bridge box girder (1) into multiple areas.

7. A maintenance-free structural device for steel bridges according to claim 6, characterized in that: The box girder diaphragm (5) is provided with a maintenance manhole (6).

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