Prefabricated beam slab integral structure based on bilateral peg-discrete steel plate mechanical connection and construction method thereof

Abstract

The application provides a prefabricated beam plate integral structure based on bilateral bolt-discrete steel plate mechanical connection and a construction method thereof, and belongs to the technical field of bridge engineering.The application comprises: a prefabricated prestressed concrete beam; a full-thickness prefabricated concrete bridge deck plate, which is prefabricated with a plurality of shear slots; a steel plate connecting piece, which has a plurality of bolts on both sides, the bolts on one side are anchored on the prefabricated prestressed concrete beam, the bolts on the other side are anchored in the shear slots, and the steel plate connecting piece is arranged discretely along the positions of the shear slots; and a vertical spacing is left between the prefabricated prestressed concrete beam and the full-thickness prefabricated concrete bridge deck plate to form a filling layer, and the filling layer is filled with concrete through the shear slots after assembly is completed.The steel plate connecting piece arranged discretely at the positions of the shear slots is used to realize efficient shear force transmission between the beam plate, the filling layer is filled with concrete, the prefabricated beam and the bridge deck plate form an integral stress system, and the advantages of stress continuity, simple construction, durability, and seismic resistance are achieved.

Description

Technical Field

[0001] This invention relates to the field of bridge engineering technology, and in particular to a precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection and its construction method. Background Technology

[0002] In prefabricated bridge structures, a reliable connection between the prestressed / precast concrete beam (PPCB) and the full-depth precast concrete deck panel (FDPC) is crucial for ensuring the structural integrity and durability. Traditional wet joints, welded reinforcing bars, or grouted sleeve connections, while capable of force transmission, suffer from drawbacks such as complex construction, large wet workload, high precision requirements, and insufficient durability and seismic performance. In recent years, mechanically assembled structures using stud-plate connections have gained attention due to their advantages of clearly defined stress distribution, high degree of prefabrication, and convenient assembly. However, current design codes have not fully explored and utilized these novel connection methods between prestressed / precast concrete beams and full-depth precast concrete deck panels. Summary of the Invention

[0003] In view of this, in order to solve the technical problems of traditional prefabricated bridge structures, such as complex construction, large amount of wet work, high precision requirements, and insufficient durability and seismic performance, this invention provides a prefabricated beam-slab integral structure and its construction method based on double-sided studs-discrete steel plate mechanical connection. By setting discretely arranged steel plate connectors at the shear groove position of the FDPC, efficient shear force transfer between beams and slabs is achieved. Concrete is poured into the filling layer to form an integral force system between the prefabricated beam and the bridge deck, so as to ensure the advantages of continuous force, simple construction, durability and seismic performance.

[0004] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a precast beam-slab integral structure based on double-sided studded—discrete steel plate mechanical connection, comprising: Precast prestressed concrete beams; The bridge deck is made of full-thickness precast concrete and has several shear grooves precast on it. The steel plate connectors are welded with several studs on both sides. One stud is anchored to the top surface of the precast prestressed concrete beam, and the other stud is anchored in the shear groove. The steel plate connectors are arranged discretely along the position of the shear groove. A vertical gap is left between the precast prestressed concrete beam and the full-thickness precast concrete bridge deck to form a filling layer between the beam and the deck. After the beam and deck are assembled, concrete is poured into the filling layer through the shear groove.

[0005] Preferably, the vertical spacing is not less than 50mm.

[0006] Preferably, the concrete is ultra-high performance concrete.

[0007] Preferably, steel wires or steel strands are arranged longitudinally along the bridge within the filling layer.

[0008] Preferably, reinforcing steel bars are arranged within the filling layer.

[0009] Preferably, the concrete strength grade of the precast prestressed concrete beam should be higher than that of the full-thickness precast concrete bridge deck.

[0010] Preferably, the concrete strength grade of the full-thickness precast concrete bridge deck should be lower than the concrete strength grade.

[0011] Preferably, the thickness of the steel plate connector is 25mm, the diameter of the stud should not be greater than 25mm, the distance from the edge of the steel plate connector in both directions to the center of the outermost stud should not be less than 4 times the diameter of the stud, and the number of studs anchored to the precast prestressed concrete beam is greater than the number of studs anchored in the shear groove.

[0012] Preferably, the shear groove extends along the thickness direction of the full-thickness precast concrete bridge deck.

[0013] Secondly, the present invention provides a construction method for the above-mentioned precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection, comprising the following steps: Step (1), Factory prefabrication of steel plate connectors: Processing discrete mechanical connection components with double-sided studs welded to the steel plate; Step (2), Installation of precast prestressed concrete beam and full-thickness precast concrete bridge deck: During the reinforcement binding stage of the precast prestressed concrete beam, fix the steel plate connector at the designed position on its top surface, and ensure that the bottom of the steel plate connector is in close contact with the top surface of the precast prestressed concrete beam and fixed with the template. Step (3) Pre-reservation of full-thickness precast concrete bridge deck and shear groove: When the full-thickness precast concrete bridge deck is prefabricated in the factory, shear grooves are reserved at the corresponding positions of the steel plate connectors. Step (4) On-site assembly and positioning: hoist the precast prestressed concrete beam and the full-thickness precast concrete bridge deck to make the shear groove and the steel plate connectors correspond precisely, and leave a vertical gap between them to form a filling layer; Step (5) Filling layer pouring: Pour concrete into the filling layer through the shear groove to complete the overall connection.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The stress distribution is clear: the steel plate is clearly positioned and its bottom is tightly attached to the top surface of the precast prestressed concrete beam (PPCB), and the shear force transmission path is direct.

[0015] Dispersed and uniform: Steel plates are discretely arranged along the shear groove, resulting in uniform stress distribution and flexible construction.

[0016] Overall performance: After the infill layer is poured, the precast prestressed concrete beam (PPCB) and the full-thickness precast concrete bridge deck (FDPC) are integrated, reducing interface slippage.

[0017] Compatible with prestressing: Full-thickness precast concrete bridge deck (FDPC) can be prestressed in the factory, with the infill layer steel wire / steel strand working together to transfer force.

[0018] High durability: The dense and impermeable filling layer of ultra-high performance concrete (UHPC) enhances the structural durability and fatigue performance.

[0019] Highly efficient assembly: Components are prefabricated in the factory and can be quickly assembled on site, eliminating the need for complex wet joint operations.

[0020] Good economic efficiency: Reduces the amount of steel bars used and the longitudinal steel plate arrangement, thus reducing material and construction costs.

[0021] Simple construction: It avoids the problem of difficult concrete pouring caused by excessively dense reinforcement in precast prestressed concrete beams (PPCBs) in traditional connections. Attached Figure Description

[0022] Figure 1 This is an overall schematic diagram of the present invention; Figure 2 This is a 3D view of the steel plate connector; Figure 3 This is the front view of the steel plate connector; Figure 4 This is a front view of another dimension of the steel plate connector; Figure 5 This is a bottom view of the steel plate connector; In the diagram, 1. Precast prestressed concrete beam; 2. Full-thickness precast concrete bridge deck; 3. Steel plate connectors; 4. Infill layer. Detailed Implementation

[0023] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] like Figure 1-5 As shown, this invention provides a precast beam-slab integral structure based on double-sided studded-discrete mechanical connection (DMC), comprising: Precast prestressed concrete beams (PPCBs), serving as the main load-bearing components, are concrete beams typically prefabricated in a factory or off-site, then transported to the construction site for installation. This improves construction efficiency, reduces on-site wet work, and makes quality control easier. Prestressing is applied to the concrete to enhance its tensile strength. For example, prestressing is usually achieved by tensioning steel bars or strands, thereby generating compressive stress in the concrete to counteract the tensile stress caused by external loads, enhancing the structure's load-bearing capacity and durability.

[0025] Full-thickness precast concrete bridge deck 2 (FDPC) with several precast shear grooves arranged discretely for installing the steel plate connectors 3 (DMC) described below.

[0026] The steel plate connector 3 (DMC) has several studs welded to both sides. One stud is anchored to the top surface of the precast prestressed concrete beam 1, and the other stud is anchored in the shear groove. Several steel plate connectors 3 are discretely arranged along the shear groove. The steel plate connector 3 (DMC) is preferably discretely arranged along the longitudinal direction of the bridge to avoid the material waste of traditional continuous steel plates.

[0027] A vertical spacing is provided between the precast prestressed concrete beam 1 (PPCB) and the full-thickness precast concrete bridge deck 2 (FDPC) to form an infill layer 4 between the beam and deck. After the beam and deck are assembled, concrete is poured into the infill layer 4 through the shear groove to form an integral load-bearing interface. Preferably, the vertical spacing is not less than 50mm. The concrete is preferably ordinary concrete or ultra-high performance concrete (UHPC).

[0028] In this invention, the precast prestressed concrete beam 1 (PPCB), the full-thickness precast concrete bridge deck 2 (FDPC), and the steel plate connector 3 (DMC) can all be manufactured in the factory, eliminating the need for complex wet joint operations during on-site assembly and significantly improving construction efficiency. The discrete connection method accommodates construction errors and avoids the difficulties in concrete pouring caused by excessively dense reinforcement in traditional methods.

[0029] The steel plate connector 3 (DMC) is tightly attached to the top surface of the precast prestressed concrete beam 1 (PPCB), and the shear force is directly transferred through the studs, with a clear path. The discrete arrangement of the steel plate connector 3 (DMC) ensures uniform stress distribution and avoids stress concentration. After the infill layer 4 is poured, interface slippage is reduced, and the precast prestressed concrete beam 1 (PPCB) and the full-thickness precast concrete bridge deck 2 (FDPC) form an efficient integrated load-bearing system. There is no need to arrange continuous steel plates longitudinally, reducing steel consumption. This simplifies the construction process, shortens the construction period, and reduces overall costs. The high density of the concrete infill layer 4 improves the structure's impermeability and fatigue performance.

[0030] In this invention, steel wires or steel strands are arranged along the longitudinal direction of the bridge in the filling layer 4 to cooperate with the prestressing arrangement of the bridge deck and ensure the continuity of the force transmission path and the coordination of the force.

[0031] In this invention, reinforcing steel bars are arranged within the filling layer 4 to further improve the strength or ductility of the studs.

[0032] In this invention, since the full-thickness precast concrete bridge deck 2 (FDPC) reaches its limit state before the precast prestressed concrete beam 1 (PPCB), the concrete strength grade of the precast prestressed concrete beam 1 should be higher than that of the full-thickness precast concrete bridge deck 2.

[0033] In this invention, the concrete strength grade of the full-thickness precast concrete bridge deck 2 should be lower than that of the concrete to ensure effective force transmission and comply with design principles such as "weak components, strong anchorage and strong connection".

[0034] In this invention, the thickness of the steel plate connector 3 is 25mm to ensure uniform stress on both sides of the studs. The stud diameter should conform to the specifications, such as not exceeding 25mm, and the total stud height should meet the requirements of the "Technical Specification for Post-Anchoring of Concrete Structures" (JGJ 143-2013) to avoid shearing and edge damage in the concrete. To avoid edge damage in the concrete, the upper flange width of the precast prestressed concrete beam 1 (PPCB) should be sufficiently large to allow for sufficient crack development space during the stress process.

[0035] The size of the steel plate connector 3 (DMC) is determined by the number and spacing of studs in the precast prestressed concrete beam 1 (PPCB). In this invention, the distance from the edge of the steel plate connector 3 (DMC) in both directions to the center of the outermost stud should be no less than four times the stud diameter. The welding of the studs to the steel plate in the steel plate connector 3 (DMC) should meet current national standards to ensure that shearing does not occur at the weld. The number of studs anchored to the precast prestressed concrete beam 1 is greater than the number of studs anchored in the shear groove. The spacing of the studs (transverse and longitudinal) should comply with the requirements of the "Steel Structure Design Standard" (GB 50017-2017) to avoid the stud group effect. If the stud group effect cannot be avoided, the filling material of the shear groove should be of high compressive strength (such as UHPC).

[0036] In this invention, the shear groove extends along the thickness direction of the full-thickness precast concrete bridge deck 2, that is, the depth of the shear groove is the thickness of the full-thickness precast concrete bridge deck 2 (FDPC). The dimensions of the shear groove should be determined by the spacing of the studs. The dimensions of the shear groove can be calculated according to the following empirical formula (Raed Tawadrous & George Morcous):

[0037] Where: A—Longitudinal length of the shear groove (parallel to the traffic direction) B—The lateral length of the shear groove (perpendicular to the traffic direction) a—Longitudinal spacing of the studs b—lateral spacing of the studs m — Number of longitudinal studs (single row) n — Number of transverse studs (single row) dh — Nail head diameter Ct—Construction tolerance (different construction precision requirements, it is recommended to take 50mm) (all units are mm).

[0038] Secondly, the present invention provides a construction method for the above-mentioned precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection, comprising the following steps: Step (1), Factory prefabrication of steel plate connectors 3: Processing discrete mechanical connection components with double-sided studs welded to the steel plate (such as...) Figure 1 (As shown).

[0039] Step (2), Installation of precast prestressed concrete beam 1 (PPCB) and full-thickness precast concrete bridge deck 2 (FDPC): During the reinforcement binding stage of precast prestressed concrete beam 1 (PPCB), fix the steel plate connector 3 (DMC) to its designed position on the top surface, ensuring that the bottom of the steel plate connector 3 (DMC) is in close contact with the top surface of precast prestressed concrete beam 1 (PPCB) and fixed with the template, so as to avoid any relative displacement of the steel plate during the process of pouring concrete or arranging reinforcement of precast prestressed concrete beam 1 (PPCB).

[0040] Step (3), full-thickness precast concrete bridge deck 2 (FDPC) and shear groove reservation: when the full-thickness precast concrete bridge deck 2 (FDPC) is precast in the factory, a shear groove is reserved at the position of the corresponding steel plate connector 3.

[0041] Step (4), On-site assembly and positioning: Hoist the precast prestressed concrete beam 1 (PPCB) and the full-thickness precast concrete bridge deck 2 (FDPC) to ensure precise alignment of the shear groove and the steel plate connector 3 (DMC), with a vertical gap reserved between them to form a filling layer 4. This process requires the full-thickness precast concrete bridge deck 2 (FDPC) and the precast prestressed concrete beam 1 (PPCB) to be designed and coordinated at the same stage to avoid mismatches. When assembling components on the construction site, the precast prestressed concrete beam 1 (PPCB) and the full-thickness precast concrete bridge deck 2 (FDPC) need to be separated, with a separation height of not less than 50mm.

[0042] Step (5), Filling Layer 4 Pouring: Concrete is poured into filling layer 4 through the shear groove to complete the overall connection. If reinforcing bars or wires are required, they should be arranged before pouring the concrete to complete the structure as follows. Figure 2 As shown.

[0043] In summary, this invention, through the combination of a discrete arrangement of double-sided studs and steel plates with a shear groove structure, has the advantages of a clear force path and direct transmission. Its discrete connection ensures uniform force distribution and flexible construction. By pouring concrete filling layer 4, the prestressed concrete beam (PPCB) and the full-thickness precast concrete bridge deck 2 (FDPC) achieve efficient overall stress distribution, reduce interface slippage, are compatible with the factory prestressing of the full-thickness precast concrete bridge deck 2 (FDPC), and improve the structural durability and fatigue performance. At the same time, the factory prefabrication and rapid on-site assembly of components greatly improves assembly efficiency, saves material costs, avoids the problem of excessively dense reinforcement in traditional connections, and combines economy with ease of construction.

[0044] The above description is merely a preferred embodiment of the present invention. However, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention should be covered within the scope of protection of the present invention.

Claims

1. A precast beam-slab integral structure based on double-sided studded—discrete steel plate mechanical connection, characterized in that, include: Precast prestressed concrete beams; The bridge deck is made of full-thickness precast concrete and has several shear grooves precast on it. The steel plate connectors are welded with several studs on both sides. One stud is anchored to the top surface of the precast prestressed concrete beam, and the other stud is anchored in the shear groove. The steel plate connectors are arranged discretely along the position of the shear groove. A vertical gap is left between the precast prestressed concrete beam and the full-thickness precast concrete bridge deck to form a filling layer between the beam and the deck. After the beam and deck are assembled, concrete is poured into the filling layer through the shear groove.

2. The precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection according to claim 1, characterized in that, The vertical spacing shall not be less than 50mm.

3. The precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection according to claim 1, characterized in that, The concrete is ultra-high performance concrete.

4. The precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection according to claim 1, characterized in that, The filling layer contains steel wires or steel strands arranged longitudinally along the bridge.

5. The precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection according to claim 1, characterized in that, The filling layer contains reinforcing steel bars.

6. The precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection according to claim 1, characterized in that, The concrete strength grade of the precast prestressed concrete beam should be higher than that of the full-thickness precast concrete bridge deck.

7. The precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection according to claim 1, characterized in that, The concrete strength grade of the full-thickness precast concrete bridge deck should be lower than that of the concrete itself.

8. The precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection according to claim 1, characterized in that, The thickness of the steel plate connector is 25mm, the diameter of the stud should not be greater than 25mm, the distance from the edge of the steel plate connector in both directions to the center of the outermost stud should not be less than 4 times the diameter of the stud, and the number of studs anchored to the precast prestressed concrete beam is greater than the number of studs anchored in the shear groove.

9. A precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection according to claim 1, characterized in that, The shear groove extends along the thickness direction of the full-thickness precast concrete bridge deck.

10. A construction method for a precast beam-slab integral structure based on double-sided studded-discrete steel plate mechanical connection according to any one of claims 1-9, characterized in that, Includes the following steps: Step (1), Factory prefabrication of steel plate connectors: Processing discrete mechanical connection components with double-sided studs welded to the steel plate; Step (2), Installation of precast prestressed concrete beam and full-thickness precast concrete bridge deck: During the reinforcement binding stage of the precast prestressed concrete beam, fix the steel plate connector at the designed position on its top surface, and ensure that the bottom of the steel plate connector is in close contact with the top surface of the precast prestressed concrete beam and fixed with the template. Step (3) Pre-reservation of full-thickness precast concrete bridge deck and shear groove: When the full-thickness precast concrete bridge deck is prefabricated in the factory, shear grooves are reserved at the corresponding positions of the steel plate connectors. Step (4) On-site assembly and positioning: hoist the precast prestressed concrete beam and the full-thickness precast concrete bridge deck to make the shear groove and the steel plate connectors correspond precisely, and leave a vertical gap between them to form a filling layer; Step (5) Filling layer pouring: Pour concrete into the filling layer through the shear groove to complete the overall connection.

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