Large-span bearing rail layer structural beam system

Abstract

The utility model relates to the technical field of civil engineering, and discloses a large-span rail bearing layer structural beam system which comprises a foundation structure, a frame column, a frame crossing beam and a structural plate. The frame columns are arranged on the upper portion of the foundation structure, the frame crossing beam crosses over the existing structure and is connected with at least two frame columns, the structural plate is arranged above the frame crossing beam and is connected with the frame crossing beam, and in-beam section steel and prestressed tendons are arranged in the frame crossing beam. According to the rail bearing layer structural beam system, the prestressed concrete beam technology and the steel reinforced concrete beam technology are combined, the profile steel and the prestressed tendons are arranged in the frame crossing beam at the same time, and the problem that the design requirement cannot be met due to the fact that the structural size is too large or crack control cannot be achieved when a rail bearing layer structure faces an ultra-large span is solved; under the condition of the same span and load, the structural beam system can effectively reduce the cross section size and the self weight of the beam, and more economically and reasonably meet the requirement of a building for the space below the beam.

Description

Technical Field

[0001] The utility model relates to the technical field of civil engineering, in particular to a large-span track-bearing layer structural beam system. Background Art

[0002] In recent years, the "bridge-in-one" track-bearing structure has become the preferred structural system for large-scale high-speed railway station hubs. This system allows for flexible layout of building functions and the realization of a large-span structural column grid. Typical column spacing for track-bearing structures ranges from 12 to 24 meters. For track-bearing structure main beams with spans greater than 18 meters, prestressed reinforced concrete beams or steel-concrete beams are primarily used to achieve the required span. Prestressed concrete beams are used to improve the performance of the track-bearing and elevated sections of large railway stations during normal use, enhancing the structural bearing capacity. Especially for track-bearing structures with large loads and spans, given the importance and service life (100 years) of railway track-bearing structures, stricter requirements are placed on deformation and crack control of track-bearing beams. In currently constructed railway station "bridge-in-one" track-bearing structures, the maximum span of prestressed reinforced concrete beams is 33 meters. However, as the span increases, the cross-section and deadweight of the prestressed beams significantly increase. Therefore, for larger spans, prestressed concrete beams may not meet the design requirements. Since steel-concrete beams are equipped with steel, they have higher strength, higher elastic modulus and lower material self-weight. Therefore, installing steel sections in concrete beams can effectively improve the strength and rigidity of large-span structural beams and reduce the reinforcement of large-span beams. However, as the span of the structure increases, it is difficult for the steel sections inside the steel-concrete beams to fully exert their strength due to the restrictions on the width of cracks in the track-bearing layer structure in the specifications. Therefore, for larger spans, steel-concrete beams may not meet the design requirements.

[0003] For "bridge-in-a-box" track-bearing structures spanning existing subway stations or sections, conventional prestressed concrete beams or steel-concrete beams generally fail to meet design requirements. (The former require excessively large cross-sections, significantly increasing their deadweight or failing to meet building clearance requirements under the beams; the latter face crack widths that fail to meet regulatory requirements.) Therefore, when the required span or load for the track-bearing layer of a "bridge-in-a-box" design is excessive, the structural beam systems currently used in railway projects may fail to meet design requirements due to factors such as structural safety, crack width control, and building clearance requirements. Utility Model Content

[0004] Based on the above problems, the utility model provides a large-span track-bearing layer structural beam system.

[0005] A large-span track-bearing layer structural beam system comprises: a foundation structure, frame columns, frame cross-beams, and a structural plate;

[0006] The frame columns are arranged on the upper part of the foundation structure, the frame spanning beam spans over the existing structure and is connected to at least two frame columns, the structural plate is arranged above the frame spanning beam and is connected to the frame spanning beam, and the structural plate is provided with rails;

[0007] The interior of the frame crossbeam is provided with internal beam steel and prestressed tendons. Both ends of the internal beam steel extend to the frame columns and are embedded in the interior of the frame columns. A hole is reserved on the frame column, through which the prestressed tendons pass, and the tensioning ends on both sides of the prestressed tendons are respectively fixed on the two outermost frame columns.

[0008] Furthermore, the steel sections in the beam include steel webs, steel flanges and steel stiffening ribs. The steel flanges are vertically connected to both ends of the steel webs. The steel stiffening ribs are arranged parallel to the steel webs, and their two ends are connected to the steel flanges.

[0009] Furthermore, an inner column steel frame is provided in the frame column, and the inner column steel frame is arranged and connected by two I-beams in a cross shape.

[0010] Furthermore, a structural secondary beam is provided at the lower portion of the structural plate, and the structural secondary beam is arranged perpendicular to the prestressed tendons.

[0011] Furthermore, a platform structure is arranged on the structural plate, and the platform structure is located on the side of the rails.

[0012] Furthermore, a platform roof is provided above the platform structure, the platform roof is connected to the roof structure columns, and the lower ends of the roof structure columns are connected to the frame cross beams.

[0013] Furthermore, the frame columns are cast in concrete, and ordinary steel bars in beams are arranged inside the concrete columns.

[0014] Furthermore, the foundation structure is buried under the ground surface and a safety distance is left between it and the existing structure.

[0015] The present invention has the following beneficial effects: the track-bearing layer structural beam system of the present invention combines prestressed concrete beam technology with steel-concrete beam technology, and arranges steel sections and prestressed tendons in the frame cross beam at the same time, thereby solving the problem that the track-bearing layer structure cannot meet the design requirements due to excessive structural dimensions or crack control when facing an ultra-large span, and realizes the demand for a larger span while ensuring the bearing capacity; in addition, the structural beam system of the present invention can effectively reduce the cross-sectional size of the beam and its own weight under the conditions of the same span and load, and more economically and reasonably meet the building's demand for space under the beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the along-track cross-section of the structural beam system of the utility model;

[0017] Figure 2It is a schematic cross-sectional diagram of the vertical rail of the structural beam system of the utility model;

[0018] Figure 3 This is a schematic diagram of the planar structure of the utility model after the structural beam system hides the platform ceiling;

[0019] Figure 4 It is a plan view of the foundation structure in the structural beam system of the utility model;

[0020] Figure 5 This is a cross-sectional schematic diagram of the frame cross beam at the frame column in the structural beam system of the utility model;

[0021] Figure 6 This is a cross-sectional schematic diagram of the frame spanning beam in the structural beam system of the present invention, away from the frame column.

[0022] In the figure: 1-foundation structure; 2-existing structure; 3-frame column; 4-steel frame in column; 5-frame cross beam; 6-section steel in beam; 601-section steel web; 602-section steel flange; 603-section steel stiffening rib; 7-prestressed tendons; 701-tensioning end; 702-channel; 8-structural secondary beam; 9-structural plate; 10-platform structure; 11-platform ceiling; 12-ceiling structural column; 13-ordinary steel bars in beam. DETAILED DESCRIPTION

[0023] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0024] refer to Figures 1 to 4 The utility model provides a large-span track-bearing layer structural beam system, including: a basic structure 1, frame columns 3, frame cross beams 5 and a structural plate 9.

[0025] The foundation structure 1 is buried in the soil and serves as the lowest layer of the structural beam system to bear and transfer pressure. Typically, the foundation structure 1 is constructed of concrete combined with a steel cage. The size and shape of the foundation structure 1 are sufficient to bear the load above it. Since the foundation structure 1 is buried below the surface, a sufficient safety distance must be left from other existing structures 2 underground. The safety distance is determined based on the specific geological conditions and the burial depth of the existing structures 2.

[0026] In this embodiment, the existing structure 2 is two parallel subway tunnels, and the number of foundation structures 1 is not less than two. When two foundation structures 1 are used in conjunction with the frame cross beam 5 to cross the existing structure 2, the foundation structure 1 is set on the outside of the subway tunnel; when the existing structure 2 to be crossed is very wide, the foundation structure 1 can also be arranged between the existing structures 2, but a safe distance between the foundation structure 1 and the existing structure 2 needs to be ensured.

[0027] Frame columns 3 are positioned and fixed above foundation structure 1, with their upper half located above ground. Frame columns 3 are cast from concrete and contain conventional beam reinforcement 13. Typically, frame columns 3 and foundation structure 1 are integrally cast. Frame columns 3 also contain internal steel bars 4, which are formed by two I-beams arranged in a cross-shaped pattern. These two I-beams are welded together for secure connection.

[0028] A slotted cavity is provided in the middle of the upper half of the frame column 3, through which the frame crossbeam 5 is installed. The frame crossbeam 5 is inserted into the frame column 3 and spans over the existing structure 2. In addition to ordinary steel mesh, the interior of the frame crossbeam 5 is also equipped with beam profiles 6 and prestressed tendons 7.

[0029] refer to Figure 5 and Figure 6 The longitudinal direction of the steel section 6 in the beam is arranged along the longitudinal direction of the frame cross beam 5. Both ends of the steel section 6 in the beam extend to the frame column 3 and are embedded in the interior of the frame column 3. The steel section 6 in the beam includes a steel web 601, a steel flange 602 and a steel stiffening rib 603. The steel web 601 is vertically arranged inside the frame cross beam 5. The upper and lower sides of the steel web 601 are respectively welded with steel flanges 602 vertically. The steel web 601 and the steel flange 602 are in an I-beam structure. In order to increase the bearing capacity of the steel web 601, steel stiffening ribs 603 are arranged in parallel on the left and right sides of the steel web 601. The upper and lower sides of the steel stiffening rib 603 are welded and fixed to the steel flange 602.

[0030] Both the frame columns 3 and the frame cross beams 5 are provided with pre-reserved holes 702. Prestressed tendons 7 pass through these holes 702, and their tensioning ends 701 are fixed to the two outermost frame columns 3. When the frame cross beams 5 are close to the frame columns 3, the prestressed tendons 7 are arranged in the lower half of the frame cross beams 5. When the frame cross beams 5 are far from the frame columns 3, the prestressed tendons 7 are arranged in the middle or upper middle portion of the frame cross beams 5. This ensures that the prestressed tendons 7 play a more effective load-bearing role. This embodiment employs a one-end or two-end tensioning construction method for tensioning the prestressed tendons 7. For one-end tensioning, a jack is used to tension the tendons on the frame columns 3. Shorter tendons 7 can be tensioned and anchored in one go. If the tendons 7 extend beyond the jack's travel, tensioning will not be achieved in one go. However, once the elongation reaches 150-200 mm, the oil should be immediately returned for a second tensioning operation. Each tensioning elongation should not exceed 200 mm.

[0031] refer to Figure 1A structural plate 9 is provided above the frame cross beam 5 and is connected to the frame cross beam 5. The structural plate 9 is also cast using high-strength concrete combined with steel bars. Rails and a platform structure 10 are provided on the structural plate 9, with the platform structure 10 located on either side of the rails. A platform ceiling 11 is provided above the platform structure 10 and is connected to ceiling columns 12. The lower ends of the ceiling columns 12 are connected to the frame cross beam 5. When the ceiling columns 12 are steel columns, their lower ends are fixed to the frame cross beam 5. When the ceiling columns 12 are concrete structures, the ceiling columns 12 and the frame cross beam 5 are integrally formed.

[0032] A structural secondary beam 8 is provided at the lower portion of the structural plate 9 and is arranged perpendicular to the prestressed tendons 7. The structural secondary beam 8 is used to connect the multiple structural plates 9 into one body and increase the bearing capacity of the structural plates 9.

[0033] The structural beam system of the present invention can effectively improve the structural span and structural bearing capacity of the track-bearing layer, while having the advantages of high crack resistance of prestressed beams and high bearing capacity of steel-concrete beams. While meeting the requirements of bearing capacity and crack control, it can reduce the dead weight of the frame cross beam 5, making the design more economical and reasonable.

[0034] The above description is merely a preferred embodiment of the present invention and does not represent all possible forms of the present invention. The scope of protection of the present invention is not limited to such specific descriptions and embodiments. Various other modifications and improvements based on the technical teachings disclosed in the present invention without departing from the essence of the present invention are still within the scope of protection of the present invention.

Claims

1. A large-span track-bearing layer structural beam system, characterized in that: include: A foundation structure (1), frame columns (3), frame cross beams (5), and a structural plate (9); The frame columns (3) are arranged on the upper part of the foundation structure (1); the frame cross beam (5) spans over the existing structure (2) and is connected to at least two of the frame columns (3); the structural plate (9) is arranged above the frame cross beam (5) and is connected to the frame cross beam (5); and a rail is arranged on the structural plate (9); The frame crossbeam (5) is provided with an inner beam steel (6) and a prestressed tendon (7), and both ends of the inner beam steel (6) extend to the frame column (3) and are embedded in the frame column (3); a hole (702) is reserved on the frame column (3), and the prestressed tendon (7) passes through the hole (702), and the tensioning ends (701) on both sides of the prestressed tendon (7) are respectively fixed on the two outermost frame columns (3).

2. The long-span track-bearing layer structural beam system according to claim 1, characterized in that: The inner steel section (6) of the beam comprises a steel web (601), a steel flange (602) and a steel stiffening rib plate (603), wherein the steel flange (602) is vertically connected to both ends of the steel web (601), and the steel stiffening rib plate (603) is arranged parallel to the steel web (601), and its two ends are connected to the steel flange (602).

3. The long-span track-bearing layer structural beam system according to claim 1, characterized in that: An inner column steel frame (4) is provided in the frame column (3), and the inner column steel frame (4) is composed of two I-beams arranged and connected in a cross shape.

4. The large-span track-bearing layer structural beam system according to claim 1, characterized in that: A structural secondary beam (8) is provided at the lower portion of the structural plate (9), and the structural secondary beam (8) is arranged perpendicular to the prestressed tendons (7).

5. The large-span track-bearing layer structural beam system according to claim 1, characterized in that: A platform structure (10) is arranged on the structural plate (9), and the platform structure (10) is located on the side of the rails.

6. The large-span track-bearing layer structural beam system according to claim 5, characterized in that: A platform roof (11) is provided above the platform structure (10), and the platform roof (11) is connected to a roof structure column (12), and the lower end of the roof structure column (12) is connected to the frame cross beam (5).

7. The large-span track-bearing layer structural beam system according to claim 1, characterized in that: The frame column (3) is cast by concrete, and ordinary steel bars (13) are arranged inside the frame column.

8. The long-span track-bearing layer structural beam system according to any one of claims 1 to 7, characterized in that: The foundation structure (1) is buried under the ground surface and a safety distance is left between the foundation structure (1) and the existing structure (2).

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