Steel-uhpc composite deck structure for repairing steel bridge deck

Abstract

This utility model belongs to the field of bridge structure construction technology and discloses a steel-UHPC composite bridge deck structure for repairing steel bridge decks. It includes a steel bridge deck and multiple prefabricated UHPC panels. The prefabricated UHPC panels are bonded to the top surface of the steel bridge deck. A wet joint is reserved between adjacent prefabricated UHPC panels. Multiple connectors are welded to the steel bridge deck within the wet joint. Each connector extends vertically upwards and has a ring-shaped horizontal cross-section with multiple protrusions or recesses extending horizontally on its inner or outer side. A cast-in-place UHPC panel is poured into the wet joint, enclosing the connectors and connecting with adjacent prefabricated UHPC panels and the steel bridge deck to form an integral structure. This utility model solves the problem in the prior art where traditional stud connectors are difficult to match the ultra-thin UHPC layer due to size limitations. By bonding multiple prefabricated UHPC panels to the top surface of the steel bridge deck and reserving wet joints between adjacent prefabricated panels, and using ring-shaped connectors welded to the steel bridge deck within the wet joint for connection, this utility model addresses the issue of traditional stud connectors being difficult to match with ultra-thin UHPC layers due to size specifications.

Description

Technical Field

[0001] This utility model belongs to the field of bridge structure construction technology, and in particular relates to a steel-UHPC composite bridge deck structure for repairing steel bridge decks. Background Technology

[0002] Orthotropic steel bridge decks are widely used in the deck structures of ultra-long span bridges (main span ≥ 800m) due to their lightweight, high strength, convenient construction, and excellent load-bearing capacity. However, during long-term service, this structural system has revealed two core problems that seriously affect its structural safety and service life.

[0003] First, the steel bridge deck exhibits significant fatigue cracking. Due to insufficient local stiffness in the area where the U-ribs connect to the deck, high stress concentration zones are easily formed under repeated vehicle loads. Coupled with residual stress and defects that are unavoidable during the welding process, the structure is prone to the initiation and propagation of fatigue cracks, becoming a key factor affecting the safe service of the steel bridge deck.

[0004] Secondly, traditional asphalt pavement has poor durability, commonly exhibiting problems such as rutting, spalling, and cracking. Especially under the combined effects of heavy traffic, temperature changes, and moisture erosion, the deterioration rate accelerates, with an average maintenance cycle of less than 5 years. This not only significantly increases operation and maintenance costs (average annual maintenance cost can reach 2 million yuan / km) but also frequently leads to traffic disruptions, severely restricting the operational efficiency of bridges.

[0005] To address the aforementioned issues, a steel-UHPC composite bridge deck system has been proposed in recent years. This system effectively combines ultra-high performance concrete (UHPC) layers with steel panels using shear connectors. The superior compressive strength, crack resistance, and durability of UHPC significantly improve the overall structural performance, making it a promising new bridge deck structure. However, existing technologies still face bottlenecks in connection construction: traditional stud connectors are limited by size specifications (e.g., the minimum length of a φ10 stud must be ≥40mm), making it difficult to match the structural requirements of ultra-thin UHPC layers (≤30mm); while custom-made small-sized studs are not only expensive (3-5 times that of conventional studs) but also involve complex installation processes and high welding requirements, making efficient and standardized construction difficult.

[0006] Therefore, how to develop an economical and efficient connection structure suitable for steel-UHPC composite bridge decks while ensuring connection reliability and construction efficiency has become a key technical problem that urgently needs to be solved in this field. Utility Model Content

[0007] This invention provides a steel-UHPC composite bridge deck structure for repairing steel bridge decks, thereby solving existing technical problems.

[0008] To solve the above-mentioned technical problems, the technical solution proposed by this utility model is as follows:

[0009] A steel-UHPC composite bridge deck structure for repairing steel bridge decks includes a steel bridge deck and multiple prefabricated UHPC panels. The multiple prefabricated UHPC panels are bonded to the top surface of the steel bridge deck. A wet joint is reserved between two adjacent prefabricated UHPC panels. Multiple connectors are welded to the steel bridge deck within the wet joint. Each connector extends vertically upward. The horizontal cross-section of each connector is annular, and multiple protrusions or depressions extending horizontally are provided on the inner or outer side. A cast-in-place UHPC panel is poured into the wet joint. The cast-in-place UHPC panel wraps around each connector and is connected to two adjacent prefabricated UHPC panels and the steel bridge deck to form an integral structure.

[0010] As a further improvement to the above technical solution:

[0011] Multiple connectors are arranged in an equally spaced matrix on the steel bridge deck within the wet joint.

[0012] Each of the aforementioned connectors has a threaded inner ring.

[0013] Each of the aforementioned connectors is a hexagonal nut, and a hexagonal head bolt is threaded into the hexagonal nut.

[0014] The mating parts of the hexagonal nut and the hexagonal head bolt are coated with an anti-loosening coating.

[0015] The upper surface of the hexagonal nut or hexagonal head bolt is lower than the upper surface of the precast UHPC slab, while the upper surface of the cast-in-place UHPC slab is flush with the precast UHPC slab.

[0016] Each of the prefabricated UHPC panels is bonded to the top surface of the steel bridge deck with epoxy resin adhesive.

[0017] Multiple prefabricated UHPC panels are arranged along the length of the steel bridge deck.

[0018] A steel mesh is provided between two adjacent precast UHPC slabs.

[0019] The steel reinforcement mesh includes outward-extending steel bars and longitudinal steel bars. The outward-extending steel bars are welded to two adjacent precast UHPC slabs on both sides, and the longitudinal steel bars are tied to multiple outward-extending steel bars.

[0020] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0021] By bonding multiple precast UHPC panels to the top surface of the steel bridge deck and leaving wet joints between adjacent panels, and using annular connectors welded to the steel bridge deck within the wet joints for connection, this method solves the problem in the prior art where traditional stud connectors are difficult to match the ultra-thin UHPC layer due to size limitations. The connectors feature multiple horizontally extending protrusions or recesses, enhancing the mechanical interlocking force with the cast-in-place UHPC panels. The cast-in-place UHPC panels enclose the connectors and form an integral structure with the precast UHPC panels and the steel bridge deck, effectively improving the reliability of the connection and the overall structural integrity. This avoids the high cost, complex construction, and welding difficulties associated with traditional small-sized studs, significantly improving construction efficiency and economy, and effectively solving the bottleneck problem of steel-UHPC composite bridge deck system connection construction in the prior art. The combination of bonding the precast UHPC panels and anchoring the connectors forms a collaborative shear resistance mechanism, significantly improving system reliability, effectively increasing bridge deck stiffness, suppressing fatigue cracking, and extending pavement life. This method is suitable for the efficient repair and reinforcement of ultra-long span bridges. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a structural diagram of a steel-UHPC composite bridge deck structure used for repairing steel bridge decks.

[0024] Figure 2 yes Figure 1 A schematic diagram of the structure of part A in the middle.

[0025] Legend:

[0026] 1. Steel bridge deck; 2. Precast UHPC slab; 3. Wet joint; 4. Connector; 41. Hex nut; 42. Hex head bolt; 5. Cast-in-place UHPC slab; 6. Reinforcing steel mesh; 61. Outward reinforcing bars; 62. Longitudinal reinforcing bars. Detailed Implementation

[0027] To facilitate understanding of this utility model, the following description will be provided in more comprehensive and detailed manner with reference to the accompanying drawings and preferred embodiments. However, the scope of protection of this utility model is not limited to the following specific embodiments.

[0028] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of protection of this invention.

[0029] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0030] Example: Figure 1 and Figure 2 As shown, the steel-UHPC composite bridge deck structure for repairing steel bridge decks in this embodiment includes a steel bridge deck 1 and multiple prefabricated UHPC panels 2. The multiple prefabricated UHPC panels 2 are bonded to the top surface of the steel bridge deck 1. A wet joint 3 is reserved between two adjacent prefabricated UHPC panels 2. Multiple connectors 4 are welded on the steel bridge deck 1 located in the wet joint 3. Each connector 4 extends vertically upward. The horizontal cross section of each connector 4 is annular, and multiple protrusions or depressions extending in the horizontal direction are provided on the inner or outer side. A cast-in-place UHPC panel 5 is poured in the wet joint 3. The cast-in-place UHPC panel 5 wraps around each connector 4 and is connected to two adjacent prefabricated UHPC panels 2 and the steel bridge deck 1 to form an integral structure. By bonding multiple precast UHPC panels 2 to the top surface of the steel bridge deck 1 and leaving wet joints 3 between adjacent precast panels 2, the connection is achieved using annular connectors 4 welded to the steel bridge deck 1 within the wet joints 3. This solves the problem in the prior art where traditional stud connectors are difficult to match the ultra-thin UHPC layer (≤30mm) due to size limitations. The connectors 4 have multiple protrusions or recesses extending horizontally, enhancing the mechanical interlocking force with the cast-in-place UHPC panels 5. The cast-in-place UHPC panels 5 enclose the connectors 4 and form an integral structure with the precast UHPC panels 2 and the steel bridge deck 1, effectively improving the reliability of the connection and the overall structural integrity. This avoids the high cost, complex construction, and welding difficulties of traditional small-sized studs, significantly improving construction efficiency and economy, and effectively solving the bottleneck problem of the connection structure of the steel-UHPC composite bridge deck system in the prior art. By combining the bonding of prefabricated UHPC panels 2 with the anchoring of connectors 4, a collaborative shear resistance mechanism is formed, which significantly improves the reliability of the system, effectively increases the stiffness of the bridge deck, inhibits fatigue cracking, and extends the life of the pavement layer. It is suitable for the efficient repair and reinforcement of ultra-long span bridges.

[0031] In this embodiment, multiple connectors 4 are arranged in a matrix with equal spacing on the steel bridge deck 1 within the wet joint 3. Their transverse and longitudinal spacing is 100mm, which effectively and evenly distributes the connection stress, improves the overall structural stability and durability, avoids localized stress concentration, reduces the risk of fatigue cracks, and ensures the long-term safe service of the steel-UHPC composite bridge deck structure.

[0032] In this embodiment, each connector 4 is a hexagonal nut 41. The hexagonal nut 41 has a simple structure and is easy to manufacture. Through its ring shape and the protrusions or recesses extending horizontally, the hexagonal nut 41 enhances the mechanical locking effect with the UHPC board. This design improves the reliability of the connection and the convenience of construction, effectively solving the size and construction problems of traditional stud connectors.

[0033] In this embodiment, a hexagonal nut 41 is threaded with a hexagonal head bolt 42. The use of an M8 type hexagonal nut 41 results in a compact structure and lower cost. Its shape facilitates good engagement with the UHPC sheet, improving connection stability, simplifying construction processes, and enhancing the economy and practicality of the connector. The hexagonal nut 41 and hexagonal head bolt 42 have a wide range of size thresholds and are inexpensive. Using them instead of size-limited studs and expensive custom-made small studs not only solves the problem of studs being difficult to use as shear connectors between thin-layer UHPC and steel bridge decks, but their low cost also brings significant economic benefits.

[0034] In this embodiment, the hexagonal head bolt 42 can be adjusted in depth within the hexagonal nut 41, thereby adjusting the height of the entire connector 4.

[0035] In this embodiment, the mating parts of the hexagonal nut 41 and the hexagonal head bolt 42 are coated with an anti-loosening coating. This coating effectively prevents the connector 4 from loosening, ensuring the long-term stability of the structure, improving the reliability of the connection, reducing maintenance frequency, and effectively preventing loosening problems caused by vibration or load. This enhances the safety and service life of the steel-UHPC composite bridge deck structure.

[0036] In this embodiment, the upper surface of the hexagonal nut 41 or hexagonal head bolt 42 is lower than the upper surface of the precast UHPC slab 2, and the upper surface of the cast-in-place UHPC slab 5 is flush with the precast UHPC slab 2. The height of the hexagonal nut 41 is less than 2 / 3 of the thickness of the UHPC layer. This avoids the impact of the connectors on the flatness of the bridge deck, ensures the smoothness and construction quality of the overall bridge deck structure, effectively achieves seamless connection between bridge deck panels, improves the overall load-bearing capacity and durability of the bridge deck, and solves the construction difficulties and safety hazards caused by protruding components in traditional connection methods.

[0037] In this embodiment, each prefabricated UHPC panel 2 is bonded to the top surface of the steel bridge deck 1 using epoxy resin adhesive. This achieves a strong bond between the prefabricated panels and the steel bridge deck, enhancing the interfacial bonding performance. The application of epoxy resin adhesive improves the durability and shear resistance of the connection, effectively prevents delamination between panels, simplifies the construction process, and improves the overall structural stability and service life.

[0038] In this embodiment, multiple prefabricated UHPC panels 2 are arranged along the length of the steel bridge deck 1. This facilitates modular installation and rapid construction of the bridge deck structure, effectively disperses stress concentration, and improves the overall load-bearing capacity and durability of the bridge deck structure. Simultaneously, combined with the advantages of the steel-UHPC composite structure in the prior art, it enhances the fatigue resistance and durability of the bridge deck.

[0039] In this embodiment, a steel mesh 6 is provided between two adjacent precast UHPC slabs 2. This enhances the overall connection strength and crack resistance at the wet joint 3, effectively improving the durability and load-bearing capacity of the bridge deck structure. It solves the problem of fatigue cracks and fissures that are easily generated by traditional connection methods in the background art, and helps to achieve the overall coordinated work of the steel-UHPC composite bridge deck, ensuring the structural safety and stability.

[0040] In this embodiment, the steel reinforcement mesh 6 includes outward-extending steel bars 61 and longitudinal steel bars 62. The outward-extending steel bars 61 are welded to two adjacent precast UHPC slabs 2 on both sides, and the longitudinal steel bars 62 are tied to multiple outward-extending steel bars 61. This ensures a firm and reliable connection, forming a stable steel reinforcement skeleton, improving the overall load-bearing performance of the wet joint 3, effectively enhancing the overall stiffness and durability of the composite bridge deck structure, and solving the bottleneck problem of connection structure in the prior art.

[0041] In this embodiment, each precast UHPC panel 2 is cast using ultra-high performance concrete, with a thickness of 30mm. Internal structural steel bars 3b are provided, with a diameter of 10mm and a spacing of 25mm. Outward-extending steel bars 61 are at least 50mm long and spaced at 25mm intervals, with adjacent units' outward-extending steel bars 61 connected by lap joints. The ultra-high performance concrete used is reactive powder concrete or ultra-high performance fiber-reinforced concrete with a compressive strength of not less than 100MPa.

[0042] In this embodiment, the steel bridge deck 1 is provided with longitudinal stiffening ribs 7 and transverse stiffening ribs 8. Orthotropic steel bridge decks commonly used in ultra-long span bridges are adopted. The thickness of the steel bridge deck 1 is 20mm. The longitudinal stiffening ribs 7 at the bottom are commonly used U-shaped ribs with a thickness of 8mm, and the transverse stiffening ribs 8 have a thickness of 10mm.

Claims

1. A steel-UHPC composite bridge deck structure for repairing a steel bridge deck comprising a steel bridge deck slab (1) and a plurality of precast UHPC slabs (2), characterized in that, Multiple prefabricated UHPC panels (2) are bonded to the top surface of the steel bridge deck (1). A wet joint (3) is reserved between two adjacent prefabricated UHPC panels (2). Multiple connectors (4) are welded on the steel bridge deck (1) located in the wet joint (3). Each connector (4) extends vertically upward. The horizontal cross section of each connector (4) is annular, and multiple protrusions or depressions extending in the horizontal direction are provided on the inner or outer side. A cast-in-place UHPC panel (5) is poured in the wet joint (3). The cast-in-place UHPC panel (5) wraps around each connector (4) and is connected with two adjacent prefabricated UHPC panels (2) and the steel bridge deck (1) to form an integral structure.

2. The steel-UHPC composite bridge deck structure for repairing steel bridge decks according to claim 1, characterized in that, Multiple connectors (4) are arranged in an equally spaced matrix on the steel bridge deck (1) within the wet joint (3).

3. The steel-UHPC composite bridge deck structure for repairing steel bridge decks according to claim 2, characterized in that, Each of the connecting parts (4) has a threaded ring inside.

4. The steel-UHPC composite bridge deck structure for repairing steel bridge decks according to claim 3, characterized in that, Each of the connecting parts (4) is a hexagonal nut (41), and a hexagonal head bolt (42) is threaded into the hexagonal nut (41).

5. The steel-UHPC composite bridge deck structure for repairing steel bridge decks according to claim 4, characterized in that, The mating parts of the hexagonal nut (41) and the hexagonal head bolt (42) are coated with an anti-loosening coating.

6. The steel-UHPC composite bridge deck structure for repairing steel bridge decks according to claim 4, characterized in that, The upper surface of the hexagonal nut (41) or hexagonal head bolt (42) is lower than the upper surface of the precast UHPC slab (2), and the upper surface of the cast-in-place UHPC slab (5) is flush with the precast UHPC slab (2).

7. The steel-UHPC composite bridge deck structure for repairing steel bridge decks according to claim 1, characterized in that, Each of the prefabricated UHPC panels (2) is bonded to the top surface of the steel bridge deck (1) with epoxy resin adhesive.

8. The steel-UHPC composite bridge deck structure for repairing steel bridge decks according to claim 1, characterized in that, Multiple prefabricated UHPC panels (2) are arranged along the length of the steel bridge deck (1).

9. The steel-UHPC composite bridge deck structure for repairing steel bridge decks according to any one of claims 1-8, characterized in that, A steel mesh (6) is provided between two adjacent precast UHPC slabs (2).

10. The steel-UHPC composite bridge deck structure for repairing steel bridge decks according to claim 9, characterized in that, The steel mesh (6) includes outward reinforcing bars (61) and longitudinal reinforcing bars (62). The outward reinforcing bars (61) are welded to two adjacent precast UHPC slabs (2) on both sides. The longitudinal reinforcing bars (62) are tied to multiple outward reinforcing bars (61).

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