Semi-assembled steel and uhcp plate shell prestressed continuous composite beam and construction method thereof

Abstract

This application relates to the field of bridge engineering construction technology, and proposes a semi-prefabricated steel and UHPC shell prestressed continuous composite beam and its construction method. The semi-prefabricated steel and UHPC shell prestressed continuous composite beam includes: a continuous beam, including a positive bending moment zone and a negative bending moment zone; steel beams arranged along the entire length of the continuous beam, or only along the positive bending moment zone; a UHPC shell, located in the lower part of the negative bending moment zone; precast slabs, including precast slabs for the positive bending moment zone and precast slabs for the negative bending moment zone, applied to the upper part of the continuous beam; shear connectors, located on the upper flange of the steel beam; concrete, filling the interior of the UHPC shell; embedded parts, for connecting with the precast slabs in the negative bending moment zone; grouting connection zones, formed on the precast slabs and corresponding to the positions of the shear connectors and embedded parts; and prestressing tendons, arranged along the beam length of the continuous beam or only in the negative bending moment zone. This enables rapid, safe, and green construction of steel and concrete continuous composite beam bridges.

Description

Technical Field

[0001] This application relates to the field of bridge engineering construction technology, and more specifically, to a semi-prefabricated steel and UHPC plate shell prestressed continuous composite beam and its construction method. Background Technology

[0002] Steel-concrete composite beams are structural forms that connect steel sections and concrete slabs into a whole using shear connectors. This structure can fully utilize the excellent tensile strength of steel and the good compressive strength of concrete, and has advantages such as high load-bearing capacity, strong span capacity, light weight, and significant economic benefits. It has been widely used in long-span bridge projects and has achieved good economic and social benefits.

[0003] Currently, steel-concrete composite beam bridges are mostly constructed using on-site concrete casting. However, on-site casting involves complex processes, a large amount of on-site work, and a long construction period, posing significant safety risks and making it difficult to guarantee construction quality. Furthermore, this method consumes a lot of energy, easily impacts the surrounding environment, and is easily constrained by external conditions such as construction space and seasonal climate. With the development of industrialized construction, fully prefabricated and semi-prefabricated composite beam bridges are gradually emerging. These bridges combine steel beams with integral or semi-prefabricated slabs, achieving standardized factory production of components. Prefabricated construction effectively overcomes the shortcomings of on-site casting, ensuring component quality while reducing on-site work, saving materials, and mitigating environmental impact. Prefabricated components can be directly hoisted mechanically upon arrival on site, resulting in high construction efficiency, minimal material storage requirements, significantly shortened construction time, and reduced labor and project costs.

[0004] However, practical applications show that using ordinary precast concrete components in prefabricated composite beams still suffers from problems such as high self-weight and poor corrosion resistance, limiting its widespread application due to factors such as transportation conditions, lifting capacity, and harsh environments. In recent years, Ultra-High Performance Concrete (UHPC), with its superior compressive and tensile strength, durability, and toughness, has provided a new approach to solving the technical bottlenecks of ordinary concrete. Meanwhile, based on the widespread application of simply supported composite beams, continuous steel-concrete composite beam bridges are gradually becoming a development trend. However, in the negative bending moment zone of the intermediate supports, the concrete flanges are under tension, and ordinary concrete is prone to cracking due to its low tensile strength; while the steel beams are under compression, posing a risk of local or overall instability. Therefore, concrete can be used to encase the steel beams in the negative bending moment zone of the continuous composite beam to enhance its lateral stiffness and stability, preventing instability and failure. Meanwhile, considering that the steel beams in the negative bending moment zone are under compression, steel beams can be installed only in the positive bending moment zone, while no steel beams are installed in the negative bending moment zone. Connecting components, such as reverse-crossing L-shaped bent steel bars, are used as shear connectors to connect the upper and lower structures in the negative bending moment zone.

[0005] Currently, many newly constructed bridges need to cross existing roads, streets, or bridges, and traffic below must not be interrupted during construction. Under such complex conditions, if cast-in-place construction is used, it will seriously affect traffic below the bridge due to the complexity of the process, the large area occupied, and the long cycle. If prefabrication is used, although it can reduce traffic interference, the prefabricated components are too heavy, and the transportation and hoisting are difficult, which restricts its application in engineering.

[0006] Therefore, how to provide a construction scheme to achieve rapid, safe and low-environmental-impact construction of continuous composite steel and concrete beam bridges is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] To address at least one of the aforementioned technical problems, the first aspect of this application proposes a semi-assembled steel and UHPC plate shell prestressed continuous composite beam.

[0008] In a second aspect, this application also proposes a construction method for a semi-prefabricated steel and UHPC slab prestressed continuous composite beam.

[0009] In view of this, the first aspect of this application proposes a semi-assembled steel and UHPC shell prestressed continuous composite beam, comprising: a continuous beam, the continuous beam including a positive bending moment zone and a negative bending moment zone; a steel beam, the steel beam being arranged along the entire length of the continuous beam, or the steel beam being arranged only along the positive bending moment zone of the continuous beam; a UHPC shell, disposed at the lower part of the negative bending moment zone; and a precast slab, including a positive bending moment zone precast slab disposed in the positive bending moment zone and a negative bending moment zone precast slab disposed in the negative bending moment zone, the precast slab being applied to the upper part of the continuous beam; Shear connectors, located on the upper flange of the steel beam, are used to connect the steel beam to the precast slab; concrete is filled inside the UHPC shell; embedded parts are embedded in the UHPC shell for connection with the precast slab in the negative moment zone; grouting connection zones are formed on the precast slab and correspond to the positions of the shear connectors and embedded parts, used to form an anchorage connection between the precast slab, the steel beam, and the UHPC shell by filling with UHPC material; prestressing tendons are arranged along the beam length of the continuous beam or only in the negative moment zone.

[0010] In conjunction with the first aspect, in some feasible ways, the steel beam is a solid-web I-beam or a honeycomb I-beam.

[0011] In conjunction with the first aspect, in some feasible ways, where the steel beams are arranged only in the positive moment zone, steel plates are welded to the ends of the steel beams, and longitudinal connectors for connecting to the negative moment zone are welded to the steel plates.

[0012] In conjunction with the first aspect, in some feasible ways, the semi-prefabricated steel and UHPC slab prestressed continuous composite beam further includes: connecting components and embedded connectors, wherein the connecting components are located in the negative bending moment zone, and the embedded connectors are located at the ends of the precast slabs in the negative bending moment zone. The connecting components are one or more combinations of the following structures: reverse-crossing L-shaped bent steel bars; inverted crossing U-shaped bent steel bars; steel plates with welded L-shaped bent steel bars and studs; and steel plates with welded studs.

[0013] In conjunction with the first aspect, in some feasible embodiments, the grouting connection zone includes: a first grouting zone, located in the precast slab of the negative bending moment zone, corresponding to the shear connector or connecting component; a second grouting zone, located in the precast slab of the negative bending moment zone, corresponding to the embedded part; a third grouting zone, located in the precast slab of the positive bending moment zone, corresponding to the shear connector; and a fourth grouting zone, located in the precast slab of the positive bending moment zone, corresponding to the embedded connector.

[0014] In conjunction with the first aspect, in some feasible ways, the precast slabs in the negative bending moment zone are UHPC slabs, UHPC-NC composite slabs, or UHPC composite slabs with U-shaped steel plates; the precast slabs in the positive bending moment zone are UHPC / NC slabs.

[0015] In conjunction with the first aspect, in some feasible ways, the semi-prefabricated steel and UHPC shell prestressed continuous composite beam also includes: a steel reinforcement cage, set in the UHPC shell cavity or the web area of ​​the steel beam, the steel reinforcement cage including longitudinal bars and stirrups, the steel reinforcement cage being an integral steel reinforcement cage or a segmented steel reinforcement cage.

[0016] The second aspect of this application proposes a construction method for a semi-prefabricated steel and UHPC slab shell prestressed continuous composite beam, comprising the following steps: prefabricating a UHPC shell, steel beams, prefabricated slabs in the negative bending moment zone, prefabricated slabs in the positive bending moment zone, and a reinforcing steel cage; hoisting and fixing the prefabricated UHPC shell into position; arranging the steel beams: arranging the steel beams along the entire length of the continuous beam, or arranging the steel beams only in the positive bending moment zone of the continuous beam; using anchors and pads, arranging prestressing tendons along the beam length or only in the negative bending moment zone; pouring concrete into the cavity of the UHPC shell to form the main beam body; hoisting the prefabricated slabs in the positive bending moment zone and the prefabricated slabs in the negative bending moment zone to their respective areas; grouting connection: pouring UHPC material into the grouting connection area reserved on the prefabricated slab, anchoring the shear connectors and embedded parts through the UHPC material, so that the prefabricated slab, steel beam, and UHPC shell form an integral whole; tensioning the prestressing tendons according to the preset tension control stress value.

[0017] In conjunction with the second aspect, in some feasible methods, arranging the steel beam along the entire length of the continuous beam includes: placing the steel beam in the UHPC shell along the length direction of the continuous beam and placing the reinforcing cage inside the cavity of the UHPC shell; arranging the steel beam only in the positive bending moment zone of the continuous beam includes: placing the steel beam at the designed position in the positive bending moment zone and hoisting and fixing the connecting components and the reinforcing cage into the cavity of the UHPC shell in the negative bending moment zone; wherein the connecting components are at least one of the following structures: reverse-crossing L-shaped bent reinforcing bars, inverted crossing U-shaped bent reinforcing bars, steel plates with welded L-shaped bent reinforcing bars and studs, and steel plates with welded studs.

[0018] In conjunction with the second aspect, in some feasible methods, the grouting connection step specifically includes: The shear connector on the steel beam is embedded into the third grouting zone of the precast slab in the positive bending moment zone, and UHPC material is injected into the grouting connection zone. Embedded connectors on the precast slab in the negative bending moment zone are inserted into the fourth grouting zone of the precast slab in the positive bending moment zone. When the steel beam is arranged along the entire length of the continuous beam, the embedded parts on the UHPC shell and the shear connectors on the steel beam are respectively embedded into the second grouting area and the first grouting area corresponding to the precast slab in the negative bending moment area, and UHPC material is injected into each grouting connection area. When the steel beams are only arranged in the positive bending moment zone of the continuous beam, the connecting components and embedded parts are respectively embedded in the corresponding first grouting zone and second grouting zone, and UHPC material is injected into each grouting connection zone.

[0019] Compared with related technologies, this application has the following technical advantages: This application provides a semi-prefabricated steel and UHPC slab prestressed continuous composite beam and its construction method. This semi-prefabricated steel and UHPC slab prestressed continuous composite beam combines the advantages of high load-bearing capacity, light weight, strong corrosion resistance, excellent fatigue resistance, and fast construction speed, making it an environmentally friendly new bridge structure system. Its structural design effectively reduces the risk of concrete cracking in the negative bending moment zone and local or overall instability of the steel beam, significantly improving the safety and durability of the structure. It is particularly suitable for complex construction conditions where normal traffic is maintained, such as on busy highways or above existing bridges. Furthermore, by arranging prestressing tendons along the beam length or only in the negative bending moment zone, the crack resistance and bending stiffness of the composite beam can be further improved, effectively reducing structural deformation and optimizing the structural stress performance.

[0020] Steel beams can be arranged along the entire length of a continuous beam or only in the positive bending moment zone. They can be flexibly adjusted according to actual engineering needs to adapt to different spans, loads, and other working conditions, thereby improving the applicability and flexibility of construction.

[0021] When steel beams are arranged along the entire length of a continuous beam, they can provide continuous and stable support for the entire structure, making the stress distribution more uniform under various loads, effectively enhancing the overall stiffness and load-bearing capacity of the structure, improving the stability of the structure under complex working conditions, reducing the risk of local damage, and making it suitable for situations with large spans and heavy loads.

[0022] When steel beams are arranged only along the positive bending moment zone, prefabricated connecting components can be used to connect prefabricated beams and prefabricated slabs in the negative bending moment zone. This satisfies the stress requirements of this area while saving steel, reducing material costs and structural weight. Furthermore, reducing the arrangement of steel beams in the negative bending moment zone can mitigate the adverse effects of concrete shrinkage and creep, thus optimizing the structural stress performance.

[0023] Additional aspects and advantages of this application will become apparent in the following description or may be learned by practice of this application. Attached Figure Description

[0024] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 A schematic diagram showing the arrangement of prestressed tendons along the beam length in one embodiment of this application is shown; Figure 2 A schematic diagram showing the arrangement of prestressing tendons along the negative bending moment zone in one embodiment of this application is shown; Figure 3 It shows Figure 1 Section view of the solid web steel beam I-I; Figure 4 It shows Figure 2 Sectional view of the solid web steel beam II-II; Figure 5 It shows Figure 1 Sectional view of the honeycomb steel beam I-I; Figure 6 It shows Figure 2 Sectional view of the honeycomb steel beam II-II; Figure 7 It shows Figure 3 Section IV-IV of the I-beams arranged along the beam length; Figure 8 It shows Figure 3 Section IV-IV of the I-beams arranged along the positive bending moment zone; Figure 9 It shows Figure 1 One of the III-III section views of a solid web I-beam and precast UHPC slab; Figure 10 It shows Figure 1 Section Ⅲ-Ⅲ of the solid web I-beam and precast UHPC slab (Part 2); Figure 11 It shows Figure 1 One of the III-III section views of the honeycomb I-beam and prefabricated UHPC slab; Figure 12 It shows Figure 1 Section Ⅲ-Ⅲ of the honeycomb I-beam and prefabricated UHPC slab (Part 2); Figure 13 It shows Figure 1 One of the III-III section views of the solid web I-beam and the precast UHPC-NC composite slab; Figure 14 It shows Figure 1 Section Ⅲ-Ⅲ of the solid web I-beam and prefabricated UHPC-NC composite slab (Part 2); Figure 15 It shows Figure 1 One of the III-III section views of the honeycomb I-beam and prefabricated UHPC-NC composite slab; Figure 16 It shows Figure 1 Section Ⅲ-Ⅲ of the honeycomb I-beam and prefabricated UHPC-NC composite slab (Part 2); Figure 17 It shows Figure 1 One of the III-III section views of a solid web I-beam and a prefabricated UHPC composite slab with an outer U-shaped steel plate; Figure 18 It shows Figure 1 Section Ⅲ-Ⅲ of the solid web I-beam and the prefabricated UHPC composite slab with U-shaped steel plate outer cladding; Figure 19 It shows Figure 1 One of the III-III section diagrams of the honeycomb I-beam and the prefabricated UHPC composite slab with U-shaped steel plate outer cladding; Figure 20 It shows Figure 1 Section Ⅲ-Ⅲ of the honeycomb I-beam and the prefabricated UHPC composite slab with U-shaped steel plate outer cladding; Figure 21 It shows Figure 2 The reverse-crossing L-shaped bent steel bars and the III-III section diagram of the precast UHPC slab; Figure 22 It shows Figure 2 Section III-III of the inverted cross-shaped U-shaped bent steel bars and precast UHPC slab; Figure 23 It shows Figure 2 Section III-III of the steel plate with welded L-shaped bent steel bars and studs and the precast UHPC slab; Figure 24 It shows Figure 2Section III-III of the steel plate for the welded studs and the precast UHPC panel; Figure 25 It shows Figure 2 The reverse-crossing L-shaped bent steel bars and the III-III section of the precast UHPC-NC slab; Figure 26 It shows Figure 2 Section III-III of the inverted cross-shaped U-shaped bent steel bars and precast UHPC-NC slab; Figure 27 It shows Figure 2 Section III-III of the inverted cross-shaped U-shaped bent steel bars and precast UHPC-NC slab; Figure 28 It shows Figure 2 Section III-III of the steel plate for the welded studs and the precast UHPC-NC plate; Figure 29 It shows Figure 2 Section III-III of the UHPC composite slab with reverse intersecting L-shaped bent steel bars and prefabricated U-shaped steel plate outer wrapping; Figure 30 It shows Figure 2 Section III-III of the UHPC composite slab with inverted cross-shaped U-shaped bent steel bars and prefabricated U-shaped steel plate outer casing; Figure 31 It shows Figure 2 Section III-III of the steel plate with welded L-shaped bent steel bars and studs and the prefabricated U-shaped steel plate UHPC composite slab; Figure 32 It shows Figure 2 Section III-III of the steel plate for welded studs and the prefabricated U-shaped steel plate UHPC composite slab; Figure 33 A top view of a prefabricated UHPC / NC slab in the positive bending moment zone is shown in one embodiment of this application; Figure 34 A top view of a precast UHPC slab in the negative bending moment zone is shown in one embodiment of this application; Figure 35 A top view schematic diagram of a prefabricated UHPC-NC composite slab in the negative bending moment zone according to one embodiment of this application is shown; Figure 36 This paper shows a top view of a prefabricated UHPC composite slab with an outer U-shaped steel plate in the negative bending moment zone according to one embodiment of this application. Figure 37 A side view of a prefabricated UHPC shell according to one embodiment of this application is shown; Figure 38 It shows Figure 37 A schematic diagram of the V-V section; Figure 39This paper shows a side view of a solid-web I-beam in one embodiment of the present application. Figure 40 It shows Figure 39 Schematic diagram of the VI-VI section; Figure 41 A side view of a honeycomb I-beam is shown in one embodiment of this application; Figure 42 It shows Figure 41 Schematic diagram of the VII-VII section; Figure 43 A schematic diagram of an integral steel reinforcement cage according to one embodiment of this application is shown; Figure 44 A schematic diagram of a segmented steel reinforcement cage according to one embodiment of this application is shown; Figure 45 A schematic diagram of a prestressed tendon pad and anchorage in one embodiment of this application is shown; Figure 46 A schematic flowchart of the construction method of a semi-assembled steel and UHPC plate shell prestressed continuous composite beam according to one embodiment of this application is shown. in, Figures 1 to 45 The correspondence between the reference numerals and component names in the attached drawings is as follows: 1—Embedded part; 2—UHPC shell; 3—Prestressed tendon; 4—Anchorage; 5—Plate; 6—Solid web I-beam; 7—Honeycomb I-beam; 8—Stud; 9—Steel plate; 10—Longitudinal connector; 11—Reverse cross L-shaped bent reinforcement; 12—Inverted cross U-shaped bent reinforcement; 13—Steel plate with welded L-shaped bent reinforcement and studs; 14—Steel plate with welded studs; 15—UHPC plate; 16—UHPC-NC composite plate; 16-1— UHPC section; 16-2—NC section; 17—UHPC composite slab with outer U-shaped steel plate; 17-1—UHPC section; 17-2—U-shaped steel plate section; 18—First grouting zone; 19—Second grouting zone; 20—Embedded connectors; 21—UHPC / NC plate; 22—Third grouting zone; 23—Fourth grouting zone; 24—Longitudinal reinforcement; 25—Stirrups; 26—Reinforcing steel cage; 27—Concrete; 100—Positive bending moment zone; 200—Negative bending moment zone. Detailed Implementation

[0025] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0026] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0027] The following reference Figures 1 to 46 This application describes a semi-assembled steel and UHPC slab prestressed continuous composite beam and its construction method according to some embodiments.

[0028] like Figures 1 to 45 As shown, the first aspect of this application provides a semi-assembled steel and UHPC shell prestressed continuous composite beam, comprising: a continuous beam, the continuous beam including a positive bending moment zone 100 and a negative bending moment zone 200; steel beams, the steel beams being arranged along the entire length of the continuous beam, or the steel beams being arranged only along the positive bending moment zone 100 of the continuous beam; a UHPC shell 2, disposed at the lower part of the negative bending moment zone 200; and precast slabs, including precast slabs disposed in the positive bending moment zone 100 and precast slabs disposed in the negative bending moment zone 200, the precast slabs being applied to the continuous beam. Upper part; shear connector, set on the upper flange of the steel beam, used to connect the steel beam and the precast slab; concrete 27, filled inside the UHPC shell 2; embedded part 1, embedded in the UHPC shell 2, used to connect with the precast slab in the negative moment zone; grouting connection zone, opened on the precast slab and corresponding to the positions of the shear connector and embedded part 1, used to form an anchorage connection between the precast slab and the steel beam and the UHPC shell 2 by filling with UHPC material; prestressed tendons 3, arranged along the beam length of the continuous beam or only arranged in the negative moment zone 200.

[0029] The semi-prefabricated steel and UHPC shell prestressed continuous composite beam provided in this application includes a continuous beam, a steel beam, a UHPC shell 2, precast slabs, shear connectors, concrete 27, embedded parts 1, a grouted connection zone, and prestressing tendons 3. The UHPC shell 2 is located at the lower part of the negative bending moment zone 200. Combined with the internal concrete 27, it significantly improves the overall stiffness and strength of the structure, enhances its bending and shear resistance, and allows the composite beam to better adapt to complex loads, thereby improving the safety and stability of the structure. UHPC material possesses excellent properties such as high strength and high durability. Its application in the shell and grouted connection zone fully utilizes its material advantages, further enhancing the comprehensive performance of the composite beam. Simultaneously, by rationally utilizing the characteristics of different materials, a balance between lightweight structure and high performance is achieved.

[0030] Using precast slabs, including precast slabs for the positive bending moment zone and precast slabs for the negative bending moment zone, allows for prefabrication in the factory in advance, reducing on-site construction procedures and time, improving construction efficiency, while ensuring the quality of precast slabs and reducing on-site construction errors.

[0031] Shear connectors effectively connect the steel beams and precast slabs. Grouting the connection zone with UHPC material anchors the precast slabs to the steel beams and UHPC shell 2. Embedded parts 1 further strengthen the connection. These multiple connection methods work synergistically to ensure tight integration of all components, allowing them to share the load and improving the overall structural integrity. Prestressed tendons 3 are arranged along the length of the continuous beam or only in the negative bending moment zone 20°, effectively improving the structural stress performance, reducing deformation and cracking, enhancing durability, and extending service life.

[0032] This application provides a semi-prefabricated steel and UHPC (Ultra-High-Pressure Polymer) prestressed continuous composite beam. This composite beam combines advantages such as high load-bearing capacity, light weight, strong corrosion resistance, superior fatigue resistance, and rapid construction speed, making it an environmentally friendly new bridge structural system. Its structural design effectively reduces the risk of cracking in the concrete at 200mm in the negative bending moment zone and local or overall instability of the steel beam, significantly improving the safety and durability of the structure. It is particularly suitable for complex construction conditions where normal traffic is maintained, such as on busy highways or above existing bridges. Furthermore, by arranging prestressing tendons 3 along the beam length or only in the negative bending moment zone 200mm, the crack resistance and bending stiffness of the composite beam can be further improved, effectively reducing structural deformation and optimizing the structural stress performance.

[0033] In some embodiments provided in this application, the steel beam is a solid web I-beam 6 or a honeycomb I-beam 7.

[0034] In this embodiment, the solid-web I-beam 6 has a simple structure and is easy to manufacture. It ensures that the steel beam has high strength and stiffness, effectively resisting bending deformation under positive bending moment, and providing stable and reliable support for the entire composite beam. At the same time, the solid-web structure makes the stress distribution of the steel beam relatively uniform when under stress, making it less prone to local stress concentration, thus improving the safety and durability of the structure.

[0035] The honeycomb I-beam 7, while maintaining a certain strength, reduces the self-weight of the steel beam through its unique honeycomb structure, thereby reducing material usage and saving costs. Furthermore, the honeycomb structure increases the moment of inertia of the steel beam section, further improving bending stiffness and enhancing the overall stability of the composite beam. This makes it particularly suitable for engineering scenarios with strict weight restrictions and requiring large spans.

[0036] In some embodiments provided in this application, when the steel beam is arranged only in the positive bending moment zone 100, a steel plate is welded to the end of the steel beam, and a longitudinal connector 10 for connecting with the negative bending moment zone 200 is welded to the steel plate.

[0037] In this embodiment, the steel beams are only arranged in the positive bending moment zone 100, which can fully utilize the mechanical properties of steel in the tension zone, effectively resist the tensile stress generated by the positive bending moment, and achieve rational use of materials. At the same time, welding steel plates to the ends of the steel beams can significantly enhance the local strength and stiffness of the ends, prevent damage caused by stress concentration, and thus improve the overall structural safety.

[0038] The longitudinal connector 10 on the steel plate provides a stable anchor point for the connection with the negative bending moment zone 200, ensuring a reliable connection between the steel beam and the negative bending moment zone 200. Through this connection structure, the entire composite beam can form a continuous and integral force-bearing system under the combined action of positive and negative bending moments, effectively transferring internal forces and reducing structural deformation.

[0039] In some embodiments provided in this application, the semi-assembled steel and UHPC slab shell prestressed continuous composite beam further includes: connecting components and embedded connectors 20. The connecting components are disposed in the negative bending moment zone 200, and the embedded connectors 20 are disposed at the ends of the precast slabs in the negative bending moment zone. The connecting components are one or more combinations of the following structures: reverse cross L-shaped bent steel bars 11; inverted cross U-shaped bent steel bars 12; steel plates 13 with welded L-shaped bent steel bars and studs; and steel plates 14 with welded studs.

[0040] In this embodiment, the connecting components adopt structures such as reverse cross L-shaped bent steel bars 11 and inverted cross U-shaped bent steel bars 12, which can better adapt to the stress characteristics of the negative bending moment zone 200, effectively increase the tensile and shear resistance of the connecting parts, make the connection between the precast slab and the steel beam and other structures in the negative bending moment zone more stable, and improve the structural integrity of the composite beam under the action of negative bending moment.

[0041] Steel plate 13 with welded L-shaped bent steel bars and studs, and steel plate 14 with welded studs are used as connecting parts. The studs can enhance the bonding force and mechanical interlocking force between the steel plate and the concrete 27. The L-shaped bent steel bars further increase the connection length and anchoring effect. The combination of multiple structures improves the reliability of the connection and reduces structural safety hazards caused by loose or failed connections.

[0042] In some embodiments provided in this application, the grouting connection area includes: a first grouting area 18, which is formed in the precast slab in the negative bending moment area and corresponds to the shear connector or connecting component; a second grouting area 19, which is formed in the precast slab in the negative bending moment area and corresponds to the embedded part 1; a third grouting area 22, which is formed in the precast slab in the positive bending moment area and corresponds to the shear connector; and a fourth grouting area 23, which is formed in the precast slab in the positive bending moment area and corresponds to the embedded connector 20.

[0043] In this embodiment, the grouting connection area includes a first grouting area 18, a second grouting area 19, a third grouting area 22, and a fourth grouting area 23. The first grouting area 18 corresponds to the shear connector or connecting component in the negative bending moment area 200, the second grouting area 19 corresponds to the embedded part 1, and the third grouting area 22 and the fourth grouting area 23 correspond to the shear connector and the embedded part 20 in the positive bending moment area 100, respectively. This precise correspondence allows the UHPC material to fully fill each key connection part, ensuring that the precast slab is tightly anchored to the steel beam, UHPC shell 2, etc., forming a reliable overall structure that effectively resists positive and negative bending moments, thereby improving the load-bearing capacity and stability of the composite beam.

[0044] The positive bending moment zone 100 and the negative bending moment zone 200 have different stress characteristics, and the subdivision of grouting zones allows for targeted treatment. The negative bending moment zone 200 is prone to tensile stress; the first grouting zone 18 and the second grouting zone 19 reinforce the connection to prevent separation of the precast slab from the steel beam. The positive bending moment zone 100 is mainly under compression; the third grouting zone 22 and the fourth grouting zone 23 ensure stable connections, avoid localized damage, and allow the composite beam to bear stress well in different areas.

[0045] Clearly defining the grouting zone facilitates precise operation during construction, ensures the quality of UHPC material filling, reduces construction errors, improves construction efficiency, and ensures that the composite beam connection quality meets design requirements.

[0046] In some embodiments provided in this application, the precast slab in the negative bending moment zone is a UHPC slab 15, a UHPC-NC composite slab, or a UHPC composite slab 17 with an outer U-shaped steel plate; the precast slab in the positive bending moment zone is a UHPC / NC slab 21.

[0047] In this embodiment, the negative bending moment zone 200 is subjected to complex stresses and is prone to tensile stress. UHPC plate 15, UHPC-NC composite plate, or UHPC composite plate 17 with an outer U-shaped steel plate are used. Utilizing the high strength and high toughness of UHPC, tensile stress can be effectively resisted, crack formation reduced, and structural durability improved. The positive bending moment zone 100 is mainly under compression, and UHPC / NC plate 21 is used. While meeting the stress requirements, the appropriate plate can be flexibly selected based on actual engineering costs and other factors, balancing performance and economy.

[0048] The combination of different materials fully leverages the advantages of each material. UHPC material enhances the overall strength and stiffness of the structure; the UHPC composite slab with outer U-shaped steel plate further enhances the bending and shear resistance of the precast slab in the negative bending moment zone, enabling the composite beam to maintain good mechanical properties in different areas.

[0049] Precast slabs can be manufactured in the factory and installed on site. Selecting the appropriate type of precast slab for different areas facilitates construction operations, improves construction efficiency, ensures construction quality, and helps shorten the project duration.

[0050] In some embodiments provided in this application, the semi-assembled steel and UHPC shell prestressed continuous composite beam further includes: a steel reinforcement cage 26, which is disposed in the cavity of the UHPC shell 2 or in the web area of ​​the steel beam. The steel reinforcement cage 26 includes longitudinal bars 24 and stirrups 25. The steel reinforcement cage 26 is an integral steel reinforcement cage or a segmented steel reinforcement cage.

[0051] In this embodiment, the reinforcing cage 26 includes longitudinal bars 24 and stirrups 25. The reinforcing cage 26 is placed within the UHPC shell 2 cavity or in the web region of the steel beam. The longitudinal bars 24 effectively withstand tensile stress, while the stirrups 25 restrain the lateral deformation of the concrete 27. Their synergistic effect significantly improves the strength and stiffness of the UHPC shell 2 and the surrounding structure of the steel beam, enabling the composite beam to better resist bending moments, shear forces, and other forces, enhancing overall stability and reducing the risk of structural deformation and failure.

[0052] Whether it's a monolithic or segmented steel reinforcement cage, it can tightly connect the UHPC shell 2, steel beams, and other components together to form an organic whole. During stress, the components can work together and deform in unison, effectively transferring internal forces and avoiding premature structural failure due to localized stress concentration, thus improving the reliability and durability of the composite beam.

[0053] Integral steel reinforcement cages facilitate hoisting and installation, improving construction efficiency; segmented steel reinforcement cages, on the other hand, can be flexibly adjusted and assembled according to on-site construction conditions and structural characteristics, adapting to different complex working conditions, reducing construction difficulty, and ensuring construction quality.

[0054] like Figure 46 As shown, the second aspect of this application provides a construction method for a semi-prefabricated steel and UHPC slab shell prestressed continuous composite beam, including the following steps: S202: Precast UHPC shell, steel beams, precast slabs in negative bending moment zone, precast slabs in positive bending moment zone, and steel reinforcement cage; S204: Hoist the prefabricated UHPC shell into place and secure it; S206: Arrangement of steel beams: Arrange steel beams along the entire length of the continuous beam, or arrange steel beams only in the positive bending moment zone of the continuous beam; S208: Using anchorages and pads, prestressing tendons are arranged along the beam length or only in the negative bending moment zone; S210: Pour concrete into the cavity of the UHPC shell to form the main beam structure; S212: Hoist the precast slabs in the positive bending moment zone and the precast slabs in the negative bending moment zone to their respective areas; S214: Grouting connection: UHPC material is poured into the grouting connection area reserved on the precast slab, and the shear connector and embedded parts are anchored by the UHPC material, so that the precast slab, steel beam and UHPC shell form an integral whole; S216: Tension the prestressed tendons according to the preset tension control stress value.

[0055] The construction method for the semi-prefabricated steel and UHPC slab-shell prestressed continuous composite beam provided in this application adopts prefabricated components, including the UHPC shell, steel beams, prefabricated slabs in the positive bending moment zone and negative bending moment zone, and steel reinforcement cage. This enables standardized factory production, effectively controls component quality, and reduces on-site construction errors. Furthermore, after prefabrication, each component is transported to the site for assembly, significantly shortening the on-site construction cycle and improving construction efficiency.

[0056] Steel beams can be arranged along the entire length of a continuous beam or only in the positive bending moment zone. They can be flexibly adjusted according to actual engineering needs to adapt to different spans, loads, and other working conditions, thereby improving the applicability and flexibility of construction methods.

[0057] By pouring UHPC material into the grouting connection area reserved in the precast slab, the shear connectors and embedded parts are anchored, and the precast slab, steel beam and UHPC shell form an integral whole. The connection method is reliable and ensures the structure's ability to work together under complex loads.

[0058] The construction method for the semi-prefabricated steel and UHPC slab prestressed continuous composite beam provided in this application has clear construction steps, and each stage can be carried out in an orderly manner, which facilitates construction management and quality control. The arrangement of prestressing tendons and the tensioning control stress value can be flexibly adjusted according to actual project needs, better adapting to different design requirements and working conditions.

[0059] In some embodiments provided in this application, arranging the steel beam along the entire length of the continuous beam includes: placing the steel beam in the UHPC shell along the length direction of the continuous beam, and placing the reinforcing steel cage inside the cavity of the UHPC shell; arranging the steel beam only in the positive bending moment zone of the continuous beam includes: placing the steel beam at the designed position in the positive bending moment zone, and hoisting the connecting components and the reinforcing steel cage into the cavity of the UHPC shell in the negative bending moment zone and fixing them; wherein, the connecting components are at least one of the following structures: reverse cross L-shaped bent reinforcing bars, inverted cross U-shaped bent reinforcing bars, steel plates with welded L-shaped bent reinforcing bars and studs, and steel plates with welded studs.

[0060] In this embodiment, with the steel beams arranged along the entire length of the continuous beam, the reinforcing steel cage is placed inside the UHPC shell cavity, and the main beam body is formed after concrete is poured, which enhances the overall strength and stiffness of the structure. Arranging prestressed tendons along the beam length or only in the negative bending moment region can effectively improve the structural stress, reduce crack generation, and improve the durability and crack resistance of the structure.

[0061] When steel beams are arranged only in the positive bending moment zone, the advantages of steel in the tension zone can be concentrated to effectively resist the tensile stress generated by the positive bending moment, thus making full use of the material properties. In the negative bending moment zone, a specific design is adopted, with connecting components and steel reinforcement working together to enhance the tensile and shear resistance of this area. Together with the steel beams in the positive bending moment zone, they form a reasonable stress system, improving the overall load-bearing capacity of the composite beam and adapting to complex load conditions.

[0062] The connecting components come in various forms. Reverse cross L-shaped bent steel bars and inverted cross U-shaped bent steel bars can increase the anchorage length and mechanical interlocking force through their own shape. Steel plates with welded L-shaped bent steel bars and studs, and steel plates with welded studs can enhance the bond with concrete. The combination of various connecting components can ensure a tight connection between the precast slab in the negative bending moment zone and the UHPC shell, reducing the risk of loosening or failure of the connection.

[0063] The steel beams are placed at their designed positions in the positive bending moment zone, while the connecting components and steel reinforcement cage are hoisted into the UHPC shell cavity in the negative bending moment zone and fixed. The construction steps are clear and the operation is relatively simple. Each component can be prefabricated and installed on-site, which helps improve construction efficiency, shorten the construction period, and ensure construction quality.

[0064] In some embodiments provided in this application, the grouting connection step specifically includes: embedding the shear connector on the steel beam into the third grouting zone of the precast slab in the positive bending moment zone, and injecting UHPC material into the grouting connection zone; embedding the pre-embedded connector on the precast slab in the negative bending moment zone into the fourth grouting zone of the precast slab in the positive bending moment zone; when the steel beam is arranged along the entire length of the continuous beam, embedding the pre-embedded part on the UHPC shell and the shear connector on the steel beam into the second and first grouting zones corresponding to the precast slab in the negative bending moment zone, and injecting UHPC material into each grouting connection zone; when the steel beam is only arranged in the positive bending moment zone of the continuous beam, embedding the connecting parts and the pre-embedded parts into the corresponding first and second grouting zones, and injecting UHPC material into each grouting connection zone.

[0065] In this embodiment, embedding the steel beam shear connector into the third grouting zone of the precast slab in the positive bending moment zone and injecting UHPC material ensures a tight bond between the steel beam and the precast slab in the positive bending moment zone, effectively transferring shear force and preventing relative slippage between the two. Similarly, embedding and injecting each component in the corresponding grouting zone in the negative bending moment zone allows the precast slab in the negative bending moment zone to form a stable whole with the UHPC shell, steel beam, etc., improving the overall load-bearing capacity and stability of the composite beam.

[0066] UHPC material possesses high strength and high toughness. After filling the grouting area, it can improve the stress distribution of the structure and reduce stress concentration. Under the combined action of positive and negative bending moments, the components are reliably connected through UHPC material, enabling them to work together better to resist bending moments, shear forces, and other forces, thereby enhancing the structure's crack resistance and durability.

[0067] Clearly defining the location requirements for each component embedded in the grouting zone facilitates construction operations and quality control. Injecting UHPC material ensures a tight connection, reduces gaps and defects, improves connection quality, ensures the composite beam meets design requirements, and lowers subsequent maintenance costs.

[0068] like Figures 1 to 46 As shown in the specific embodiment, the construction process of the semi-prefabricated steel and UHPC slab prestressed continuous composite beam is as follows: 1. Precast component fabrication (1) Fabrication of UHPC shell: According to the design requirements, fabricate and set up the template, fix the embedded part 1, and pour UHPC material to form a UHPC shell 2; (2) Prepare prestressed tendons and anchorages: Prepare prestressed tendons 3, as well as matching anchorages 4 and pads 5, according to the specifications, strength grade and length required by the design. (3) Fabrication of steel beams and shear connectors: According to design requirements, when the steel beams are arranged along the entire length of the continuous beam, solid-web I-beams 6 or honeycomb I-beams 7 are selected. After rust removal, shear connectors are welded at the upper flange of the solid-web I-beams 6 or honeycomb I-beams 7 at the designed spacing. The shear connectors include studs 8, bent-up bars, channel steel, square steel, etc. At the same time, pads 5 are welded at the web of the solid-web I-beams 6 or honeycomb I-beams 7. When the steel beams are arranged only along the positive bending moment zone 100 of the continuous beam, steel plates 9 need to be welded at the ends of the steel beams, and longitudinal connectors 10 need to be welded on the steel plates 9. The longitudinal connectors 10 include studs, anchor bars, threaded bars, etc. Simultaneously, reverse cross L-shaped bent steel bars 11, inverted cross U-shaped bent steel bars 12, steel plates 13 for welding L-shaped bent steel bars and studs, and steel plates 14 for welding studs are manufactured as connecting parts between the precast beam and the precast slab in the negative bending moment zone 200. (4) Fabrication of precast slabs in the negative bending moment zone: According to design requirements, fabricate UHPC slab 15, UHPC-NC composite slab 16, or UHPC composite slab 17 with U-shaped steel plate. On UHPC slab 15, UHPC-NC composite slab 16, or UHPC composite slab 17 with U-shaped steel plate, reserve the first grouting zone 18 and the second grouting zone 19 respectively at the positions of the studs 8 and the embedded parts 1. At the same time, embed the connecting parts 20 at the ends of UHPC slab 15, UHPC-NC composite slab 16, or UHPC composite slab 17 with U-shaped steel plate; wherein, UHPC-NC composite slab 16 includes UHPC part 16-1 and NC part 16-2, and UHPC composite slab with U-shaped steel plate includes UHPC part 17-1 and U-shaped steel plate part 17-2.

[0069] (5) Fabrication of precast slabs in the positive bending moment zone: Fabricate UHPC / NC slab 21 according to design requirements. On UHPC / NC slab 21, at the positions corresponding to the studs 8 and the embedded connectors 20, reserve the third grouting zone 22 and the fourth grouting zone 23 respectively; (6) Fabrication of steel reinforcement cage: According to the design requirements, the longitudinal bars 24 and stirrups 25 are tied or welded to form an integral or segmented steel reinforcement cage.

[0070] 2. Installation of prefabricated components (1) The prefabricated UHPC shell 2 is hoisted with a special lifting tool, and fixed after being accurately positioned. Its elevation and axis position are checked and adjusted to ensure that they meet the design requirements. (2) When the steel beam is arranged along the entire length of the continuous beam, the finished steel beam is placed and fixed along the beam length direction according to the design position, and the steel reinforcement cage 26 is hoisted into the cavity of the UHPC shell 2. When the steel beam is only arranged in the positive bending moment zone 100 of the continuous beam, the finished steel beam is placed in the positive bending moment zone 100 according to the design position, and the reverse cross L-shaped bent steel bars 11, or inverted cross U-shaped bent steel bars 12, or steel plates 13 with welded L-shaped bent steel bars and studs, or steel plates 14 with welded studs and steel reinforcement cage 26 are hoisted into the cavity of the UHPC shell 2 and fixed. When a segmented steel reinforcement cage is used, it needs to be assembled in the cavity of the UHPC shell 2 by mechanical connection or welding. (3) Using anchors 4 and pads 5, prestressed tendons 3 are arranged along the beam length or only in the negative bending moment zone 200; (4) Pour concrete 27 inside the UHPC shell 2 and ensure that the concrete 27 is dense; (5) Hoist the precast UHPC / NC plate 21 onto the steel beam in the positive bending moment zone 100, so that the studs 8 are precisely embedded in the third grouting zone 22, and then pour UHPC material into the third grouting zone 22; (6) Hoist the precast UHPC slab 15 or UHPC-NC composite slab 16 or UHPC composite slab 17 with U-shaped steel plate to the designated position in the negative bending moment zone 200, so that the embedded connector 20 is accurately embedded in the fourth grouting zone 23. When the steel beam is arranged along the entire length of the continuous beam, ensure that the stud 8 and the embedded part 1 are embedded in the first grouting zone 18 and the second grouting zone 19 respectively; when the steel beam is only arranged in the positive bending moment zone 100 of the continuous beam, ensure that the reverse cross L-shaped bent steel bar 11, or the inverted cross U-shaped bent steel bar 12, or the steel plate 13 with welded L-shaped bent steel bar and stud, or the steel plate 14 with welded stud and embedded part 1 are embedded in the first grouting zone 18 and the second grouting zone 19 respectively. Then, pour UHPC material in the first grouting zone 18, the second grouting zone 19 and the fourth grouting zone 23; (7) Tension the prestressed tendon 3 according to the preset tension control stress value, thus completing the construction of the semi-assembled steel and UHPC plate shell prestressed continuous composite beam.

[0071] In this application, the term "multiple" refers to two or more unless otherwise expressly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0072] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0073] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A semi-assembled steel and UHPC plate shell prestressed continuous composite beam, characterized in that, include: A continuous beam, the continuous beam including a positive bending moment region and a negative bending moment region; The steel beam is arranged along the entire length of the continuous beam, or the steel beam is arranged only along the positive bending moment region of the continuous beam; UHPC shell, located in the lower part of the negative bending moment zone; The precast slab includes a positive bending moment zone precast slab disposed in the positive bending moment zone and a negative bending moment zone precast slab disposed in the negative bending moment zone, the precast slab being applied to the upper part of the continuous beam; A shear connector, disposed on the upper flange of the steel beam, is used to connect the steel beam to the precast slab; Concrete is used to fill the interior of the UHPC shell; Embedded parts, pre-embedded in the UHPC shell, are used to connect with the precast slab in the negative bending moment zone; A grouting connection area is provided on the precast slab and corresponds to the position of the shear connector and the embedded part. It is used to form an anchoring connection between the precast slab and the steel beam and the UHPC shell by filling it with UHPC material. Prestressing tendons are arranged along the length of the continuous beam or only in the negative bending moment zone.

2. The semi-assembled steel and UHPC plate shell prestressed continuous composite beam according to claim 1, characterized in that, The steel beam is a solid-web I-beam or a honeycomb I-beam.

3. The semi-assembled steel and UHPC plate shell prestressed continuous composite beam according to claim 1, characterized in that, When the steel beam is arranged only in the positive bending moment zone, a steel plate is welded to the end of the steel beam, and a longitudinal connector for connecting to the negative bending moment zone is welded to the steel plate.

4. The semi-assembled steel and UHPC plate shell prestressed continuous composite beam according to claim 3, characterized in that, Also includes: The connecting component and the embedded connector are provided, wherein the connecting component is disposed in the negative bending moment zone, and the embedded connector is disposed at the end of the precast slab in the negative bending moment zone. The connecting component is one or more combinations of the following structures: Reverse-crossing L-shaped bent steel bars; Inverted cross-shaped U-shaped bent steel bars; Steel plate for welding L-shaped bent reinforcing bars and studs; Steel plate for welding studs.

5. The semi-assembled steel and UHPC plate shell prestressed continuous composite beam according to claim 4, characterized in that, The grouting connection area includes: The first grouting zone is opened in the precast slab of the negative bending moment zone and corresponds to the shear connector or the connecting component. The second grouting zone is located in the precast slab of the negative bending moment zone and corresponds to the embedded parts. The third grouting zone is located in the precast slab of the positive bending moment zone and corresponds to the shear connection. The fourth grouting zone is located in the precast slab of the positive bending moment zone and corresponds to the embedded connector.

6. The semi-assembled steel and UHPC plate shell prestressed continuous composite beam according to claim 1, characterized in that, The precast slab in the negative bending moment zone is a UHPC slab, a UHPC-NC composite slab, or a UHPC composite slab with an outer U-shaped steel plate. The precast slab in the positive bending moment zone is a UHPC / NC slab.

7. The semi-assembled steel and UHPC plate shell prestressed continuous composite beam according to any one of claims 1 to 6, characterized in that, Also includes: A reinforcing steel cage is provided within the UHPC shell cavity or in the web region of the steel beam. The reinforcing steel cage includes longitudinal bars and stirrups. The reinforcing steel cage can be an integral reinforcing steel cage or a segmented reinforcing steel cage.

8. A construction method for a semi-prefabricated steel and UHPC slab prestressed continuous composite beam as described in any one of claims 1 to 7, characterized in that, Includes the following steps: Precast UHPC shell, steel beams, precast slabs in negative bending moment zone, precast slabs in positive bending moment zone, and steel reinforcement cage; The prefabricated UHPC shell is hoisted into place and secured. Arrangement of steel beams: Arrange steel beams along the entire length of the continuous beam, or arrange steel beams only in the positive bending moment zone of the continuous beam; Prestressing tendons are arranged along the beam length or only in the negative bending moment zone using anchorages and pads. Concrete is poured into the cavity of the UHPC shell to form the main beam body; The precast slabs in the positive bending moment zone and the precast slabs in the negative bending moment zone are respectively hoisted to their corresponding areas; Grouting connection: UHPC material is poured into the grouting connection area reserved on the precast slab, and the shear connector and embedded parts are anchored by the UHPC material, so that the precast slab, the steel beam and the UHPC shell form an integral whole; The prestressed tendons are tensioned according to the preset tension control stress value.

9. The construction method of the semi-prefabricated steel and UHPC plate shell prestressed continuous composite beam according to claim 8, characterized in that, The arrangement of the steel beam along the entire length of the continuous beam includes: placing the steel beam in the UHPC shell along the length of the continuous beam, and placing the steel reinforcement cage inside the cavity of the UHPC shell; The step of arranging the steel beam only in the positive bending moment zone of the continuous beam includes: placing the steel beam at the designed position in the positive bending moment zone, and hoisting the connecting components and the steel reinforcement cage into the UHPC shell cavity in the negative bending moment zone and fixing them; wherein, the connecting components are at least one of the following structures: reverse cross L-shaped bent steel bars, inverted cross U-shaped bent steel bars, steel plates with welded L-shaped bent steel bars and studs, and steel plates with welded studs.

10. The construction method of the semi-prefabricated steel and UHPC plate shell prestressed continuous composite beam according to claim 9, characterized in that, The grouting connection step specifically includes: The shear connector on the steel beam is embedded into the third grouting zone of the precast slab in the positive bending moment zone, and UHPC material is injected into the grouting connection zone. The pre-embedded connectors on the precast slab in the negative bending moment zone are embedded into the fourth grouting zone of the precast slab in the positive bending moment zone. When the steel beams are arranged along the entire length of the continuous beam, the embedded parts on the UHPC shell and the shear connectors on the steel beams are respectively embedded into the second grouting area and the first grouting area corresponding to the precast slab in the negative bending moment area; and UHPC material is injected into each grouting connection area. When the steel beams are only arranged in the positive bending moment zone of the continuous beam, the connecting components and embedded parts are respectively embedded in the corresponding first grouting zone and second grouting zone, and UHPC material is injected into each grouting connection zone.

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