Bridge deck pavement for improving vertical natural vibration frequency of pedestrian overpass

Abstract

The utility model belongs to the field of bridge structures, and relates to a bridge deck pavement for improving the vertical natural vibration frequency of a pedestrian overpass, which comprises shear reinforcements arranged on a bridge deck top plate, the shear reinforcements are connected with a steel box girder top plate through welding, a layer of reinforcement mesh is arranged on the top surface of a rigid pavement, and the thickness of a reinforcement mesh protective layer is 3cm. And the reinforcing mesh is connected with the shear reinforcing steel bars through welding. After the shear steel bars and the steel bar meshes are laid, a C40 shrinkage-compensating fine stone concrete rigid pavement layer with the thickness of 8-10 cm is poured to replace an original mortar layer with the thickness of 5-6 cm, so that the main beam structure forms a similar steel-concrete superposed beam structure, the inertia moment of the cross section of the main beam is effectively increased (the bending-resistant inertia moment of the cross section is 1.3 times larger than that of the rigid pavement layer), and the vertical natural vibration frequency of the structure is improved.

Description

Technical Field

[0001] The utility model belongs to the field of bridge structures and relates to a bridge deck pavement for improving the vertical natural vibration frequency of a pedestrian bridge. Background Art

[0002] Pedestrian bridges located in the core area of ​​the city generally use steel structure pedestrian bridges with light structure and little impact on the current traffic. However, steel structure is a flexible structure with low structural fundamental frequency, which is easy to resonate and has low comfort when pedestrians walk. Therefore, the "Technical Specifications for Urban Pedestrian Bridges and Pedestrian Tunnels" (CJJ69-95) requires that the vertical natural frequency of the upper structure of the pedestrian bridge should not be less than 3Hz. The vertical natural frequency of the structure reflects the inherent dynamic characteristics of the structure, which only depends on its own mass and stiffness distribution. Directly increasing stiffness and reducing mass are also ways to increase the frequency. However, for the steel box continuous beam structure, the increase in structural stiffness by increasing the thickness of the steel plate is almost proportional to the corresponding increase in structural mass. The effect is not obvious, and at the same time it increases the construction cost and welding construction difficulty. Increasing the beam height will make the structure look bulky and lose the light appearance of the steel structure bridge, affecting the bridge landscape. The increase in the calculated height of the web also brings about the problem of local stability of the web. To this end, we propose a bridge deck pavement that increases the vertical natural frequency of the pedestrian bridge. Utility Model Content

[0003] In view of this, the purpose of the utility model is to provide a bridge deck pavement that improves the vertical natural frequency of a pedestrian bridge, so as to solve the problem of insufficient vertical natural frequency of a steel structure pedestrian bridge proposed in the above background technology.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a bridge deck pavement for improving the vertical natural frequency of a pedestrian bridge, including a steel box girder top plate of the pedestrian bridge, characterized in that: the top surface of the steel box girder top plate of the pedestrian bridge is provided with shear steel bars, a steel mesh is laid on the shear steel bars, a C40 shrinkage compensating fine stone concrete rigid pavement layer is cast on the steel box girder top plate of the pedestrian bridge and is connected to the steel box girder top plate of the pedestrian bridge through shear steel bars and the steel mesh, and a surface stone pavement is laid on the C40 shrinkage compensating fine stone concrete rigid pavement layer.

[0005] Optionally, a plurality of groups of shear steel bars are provided between the steel mesh and the top plate of the steel box girder of the pedestrian overpass, and the shear steel bars are arranged in a plum blossom shape.

[0006] Optionally, the shear reinforcement member is in a double L-shape, and a reinforced base is provided on the bottom surface of the foundation corresponding to the top surface of the steel box girder top plate of the pedestrian bridge.

[0007] Optionally, the thickness of the C40 shrinkage compensating fine aggregate concrete rigid paving layer is 8 to 10 cm.

[0008] The beneficial effects of the utility model are as follows: the utility model replaces the original 5-6cm mortar layer with a 8-10cm thick C40 shrinkage compensating fine stone concrete rigid pavement layer, so that the main beam structure forms a similar steel-concrete composite beam structure, effectively increasing the main beam section inertia moment (section bending inertia moment is 1.3 times greater than that without a rigid pavement layer), thereby increasing the vertical natural frequency of the structure; the measure of adding a rigid pavement layer to the bridge deck can effectively increase the structural fundamental frequency, and through the setting of shear reinforcement, the pavement and the steel plate can be more closely combined and jointly stressed, and the construction is convenient, and the durability of the bridge deck pavement is improved. It will not bring about a significant increase in cost.

[0009] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and will be apparent to those skilled in the art based on the following examination and research, or can be taught from the practice of the present invention to some extent. The objectives and other advantages of the present invention can be achieved and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be described in detail below in conjunction with the accompanying drawings, in which:

[0011] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0012] Figure 2 It is a schematic diagram of A of the present utility model.

[0013] Reference numerals: 1. Pedestrian bridge steel box girder top plate; 2. Shear reinforcement; 3. Steel mesh; 4. C40 shrinkage-compensating fine stone concrete rigid pavement; 5. Surface stone pavement; 6. Strengthened base DETAILED DESCRIPTION

[0014] The following describes the implementation of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. The following embodiments and the features in the embodiments can be combined with each other without conflict.

[0015] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present utility model. In order to better illustrate the embodiments of the present utility model, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0016] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "back" and the like indicate directions or positional relationships, they are based on the directions or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0017] See also Figure 1 The utility model provides a bridge deck pavement for improving the vertical natural frequency of a pedestrian bridge, including a pedestrian bridge steel box girder top plate 1, a shear steel bar 2 is arranged on the top surface of the pedestrian bridge steel box girder top plate 1, a steel mesh 3 is laid on the shear steel bar 2, a cast-in-place C40 shrinkage compensating fine stone concrete rigid pavement layer 4 is connected to the pedestrian bridge steel box girder top plate 1 through the shear steel bar 2 and the steel mesh 3, and finally a surface stone pavement 5 is laid on the cast-in-place C40 shrinkage compensating fine stone concrete rigid pavement layer 4.

[0018] In this embodiment, the shear steel bars 2 are connected to the top surface of the steel box girder top plate 1 of the pedestrian overpass by welding, the steel mesh 3 is laid on the shear steel bars 2, and the cast-in-place C40 shrinkage compensating fine stone concrete rigid pavement layer 4 is poured. The C40 shrinkage compensating fine stone concrete rigid pavement layer 4 is firmly connected to the steel box girder top plate 1 of the pedestrian overpass through the shear steel bars 2 and the steel mesh 3. At the same time, the steel mesh 3 can make the C40 shrinkage compensating fine stone concrete rigid pavement layer 4 have better durability to prevent cracking. Finally, the surface stone pavement 5 is laid on the C40 shrinkage compensating fine stone concrete rigid pavement layer 4.

[0019] In this embodiment, the shear steel bars 2 are connected to the steel box girder top plate 1 by welding, the shear steel bars 2 have a diameter of 16 cm, the steel bar spacing is 30 cm×30 cm, the steel mesh 3 has a steel bar diameter of 8 cm, the spacing is 10 cm×10 cm, the steel mesh 3 has a protective layer thickness of 3 cm, and the steel mesh and shear steel bars are connected by welding.

[0020] In this example, see Figure 2Arranging a reinforcing base 6 on the bottom surface of the shear reinforcement 2 can make the shear reinforcement 2 more stable and more closely connected with the top plate 1 of the steel box girder of the pedestrian bridge.

[0021] The working principle of the utility model is as follows: the C40 shrinkage compensating fine stone concrete rigid pavement layer 4 is connected to the steel box girder top plate 1 of the pedestrian bridge through shear steel bars 2 and steel mesh 3, so that the entire bridge structure forms a steel-concrete composite beam structure, which effectively increases the moment of inertia of the main beam section and increases the section stiffness, thereby improving the vertical natural frequency of the pedestrian bridge.

[0022] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the utility model.

Claims

1. A bridge deck pavement for increasing the vertical natural frequency of a pedestrian bridge, including a top plate of a steel box girder of the pedestrian bridge, characterized in that: The top surface of the steel box girder top plate of the pedestrian overpass is provided with shear reinforcement, on which a steel mesh is laid, a C40 shrinkage compensating fine stone concrete rigid pavement layer is cast on the steel box girder top plate of the pedestrian overpass and connected to the steel box girder top plate of the pedestrian overpass through shear reinforcement and steel mesh, and a surface stone pavement is laid on the C40 shrinkage compensating fine stone concrete rigid pavement layer.

2. The bridge deck pavement for increasing the vertical natural frequency of a pedestrian bridge according to claim 1 is characterized in that: Several groups of shear steel bars are arranged between the steel mesh and the top plate of the steel box girder of the pedestrian overpass, and the shear steel bars are arranged in a plum blossom shape.

3. The bridge deck pavement for increasing the vertical natural frequency of a pedestrian bridge according to claim 1 is characterized in that: The shear reinforcement member is in a double L-shape, and a reinforced base is provided on the bottom surface of the foundation which is aligned with the top surface of the steel box girder top plate of the pedestrian bridge.

4. The bridge deck pavement for increasing the vertical natural frequency of a pedestrian bridge according to claim 1 is characterized in that: The thickness of C40 shrinkage compensating fine stone concrete rigid pavement layer is 8 to 10 cm.

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