Wind-resistant guardrail for long-span bridge

Abstract

The present invention provides a wind-resistant guardrail for a long-span bridge, including maintenance railings arranged on both sides of the bridge deck, and roadway guardrails arranged on both sides of the roadway of the bridge deck; the maintenance railings include a first transparent area and a first closed area arranged alternately along the bridge direction, and the roadway guardrails include a second transparent area and a second closed area arranged alternately along the bridge direction, and the first closed area and the second closed area on the same side of the bridge deck are arranged in a staggered manner. The invention processes the external structure of the maintenance railings and roadway railings on the bridge to form a semi-enclosed and semi-transparent structure, and the closed areas of the maintenance railings and roadway railings are arranged in a staggered manner, which effectively changes the flow pattern of the airflow around the bridge structure, thereby achieving the purpose of suppressing the vortex-induced vibration of the bridge.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge engineering, and in particular relates to a wind-resistant guardrail for a long-span bridge. Background Art

[0002] With the continuous advancement of construction technology and the rapid development of new materials, the span of modern bridges has continued to increase. Bridge structures are more sensitive to wind and their dynamic response is more prominent. The wind-induced vibration of structures has become a factor that restricts the design of structural stiffness, strength and stability. The aerodynamic force that causes wind-induced vibration of bridges is generated by the interaction between the airflow bypassing the bridge section and the structural vibration response. Among them, vortex-induced vibration is a wind-induced vibration phenomenon that is easy to occur in bridge structures at lower wind speeds. It is a limited amplitude vibration with a high frequency of occurrence and low wind speed. It not only affects the fatigue and strength of the structure, but also reduces the comfort of driving on the bridge deck and even endangers traffic safety. Therefore, the vortex-induced vibration problem of bridges is a very important issue for long-span bridges.

[0003] At present, studies have shown that by appropriately changing the shape of the bridge or adding some guide devices, the flow pattern around the structure can be changed by changing the cross-sectional shape, thereby changing the aerodynamic force acting on the structure, and the purpose of reducing the vortex-induced vibration of the bridge can be achieved. Therefore, it is of great significance to appropriately adjust the shape of the main beam ancillary facilities such as sidewalk railings and vehicle anti-collision guardrails to improve the aerodynamic characteristics of the main beam and reduce wind-induced vibration. Summary of the invention

[0004] The purpose of the present invention is to provide a wind-resistant guardrail for a long-span bridge, change the structural shape of the bridge's maintenance railing and roadway guardrail, and achieve the purpose of reducing the vortex-induced vibration of the bridge.

[0005] The technical solution of the present invention is to provide a wind-resistant guardrail for a large-span bridge, including inspection railings arranged on both sides of the bridge deck, and roadway guardrails arranged on both sides of the roadway of the bridge deck; the inspection railings include a first transparent area and a first closed area arranged alternately along the direction of the bridge, and the roadway guardrails include a second transparent area and a second closed area arranged alternately along the direction of the bridge, and the first closed area and the second closed area on the same side of the bridge deck are staggered.

[0006] Furthermore, the maintenance railing is a metal railing, including a plurality of first columns arranged at equal intervals along the direction of the bridge, with a railing unit between every two adjacent first columns, the first transparent area is composed of 3 to 6 railing units, and the first closed area is composed of a railing unit and a closing member that closes the railing unit.

[0007] Furthermore, a plurality of windshield strips arranged at equal intervals are provided between two adjacent first columns, and the windshield strips are arranged parallel to the first columns.

[0008] Furthermore, the intervals between two adjacent first closed areas are equal.

[0009] Furthermore, the roadway guardrail adopts a combined structure of a lower concrete guardrail and an upper steel guardrail.

[0010] Furthermore, the upper steel guardrail of the carriageway guardrail includes a plurality of second columns arranged at equal intervals along the direction of the bridge, with a guardrail unit between each two adjacent second columns, the second transparent area is composed of 3 to 6 guardrail units, and the second closed area is composed of a guardrail unit and two closing parts for closing the guardrail unit.

[0011] Furthermore, a plurality of cross beams are connected between two adjacent second columns at intervals, and the cross beams are arranged perpendicular to the second columns.

[0012] Furthermore, the intervals between two adjacent second closed areas are equal.

[0013] Furthermore, the first closed area and the second closed area on the same side of the bridge deck are arranged alternately in sequence.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) The wind-resistant guardrail of the large-span bridge provided by the present invention forms a semi-enclosed and semi-transparent structure by processing the external structure of the inspection railing and the roadway railing on the bridge. The closed areas of the inspection railing and the roadway railing are arranged in a staggered structure, which effectively changes the flow pattern of the airflow around the bridge structure, thereby achieving the purpose of suppressing the vortex-induced vibration of the bridge.

[0016] (2) Through wind tunnel tests on actual bridges, it was found that the vortex-induced vibration amplitude of the bridge was reduced from 375 mm to 57.1 mm by using the wind-resistant guardrail of the large-span bridge provided by the present invention, and the effect was very obvious.

[0017] The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the structure of the wind-resistant guardrail of the long-span bridge in the embodiment of the present invention;

[0019] Figure 2 is a schematic structural diagram of an inspection railing in an embodiment of the present invention;

[0020] Figure 3 is a schematic structural diagram of a roadway guardrail in an embodiment of the present invention;

[0021] Figure 4 It is a vortex vibration amplitude curve diagram of a bridge using conventional maintenance railings, roadway guardrails and a bridge using the wind-resistant guardrail of the present invention.

[0022] Explanation of the accompanying drawings: 1. Bridge deck; 2. Roadway guardrail; 3. Maintenance railing; 4. First column; 5. First transparent area; 6. First closed area; 7. Closure piece one; 8. Railing unit; 9. Wind shield; 10. Lower concrete guardrail; 11. Second column; 12. Second closed area; 13. Second transparent area; 14. Closure piece two; 15. Guardrail unit; 16. Crossbeam. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and 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 orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0025] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of the present invention, unless otherwise specified, "multiple" and "several" mean two or more.

[0026] like Figure 1 , Figure 2 and Figure 3As shown, this embodiment provides a wind-resistant guardrail for a long-span bridge, including an inspection railing 3 arranged on both sides of a bridge deck 1, and a roadway guardrail 2 arranged on both sides of a roadway of the bridge deck 1; the inspection railing 3 includes a first transparent area 5 and a first closed area 6 arranged alternately along the bridge direction, and the roadway guardrail 2 includes a second transparent area 13 and a second closed area 12 arranged alternately along the bridge direction, and the first closed area 6 and the second closed area 12 on the same side of the bridge deck 1 are arranged in a staggered manner, that is, the first closed area of ​​the inspection railing 3 corresponds to the second transparent area 13 of the roadway guardrail 2, and the second closed area 12 of the roadway guardrail 2 corresponds to the first transparent area 5 of the inspection railing 3. Optimally, the first closed area 6 and the second closed area 12 on the same side of the bridge deck 1 are arranged alternately in sequence. In this embodiment, by specially processing the external structure of the inspection railing 3 and the roadway railing 2 on the bridge, the inspection railing 3 and the roadway railing 2 are made semi-closed and semi-transparent, and the closed areas of the two are arranged in a staggered structure, which effectively changes the flow pattern of the airflow around the bridge structure, thereby achieving the purpose of suppressing the vortex-induced vibration of the bridge.

[0027] Specifically, the inspection railing 3 is a metal railing, which is arranged at the edge positions on both sides of the bridge deck 1, and the roadway guardrail 2 adopts a combined guardrail, that is, a combined structure of a lower concrete guardrail 10 and an upper steel guardrail.

[0028] Refine the structure of the maintenance railing 3, such as Figure 2 As shown, the inspection railing 3 includes a number of first columns 4 arranged at equal intervals along the bridge direction, a railing unit 8 is provided between each two adjacent first columns 4, and the spacing between two adjacent first columns 4 is generally 1.5-2m. The first transparent area 5 is composed of 3-6 railing units 8, and the airflow acting on the surrounding of the bridge structure can flow through the first transparent area 5. In this embodiment, the first transparent area 5 is specifically composed of 3 railing units 8; the first closed area 6 is composed of a railing unit 8 and a closure member 7 that closes the railing unit 8. The closure member 7 can be a sealing plate. The airflow acting on this first closed area 6 is blocked by the closure member 7, so that it flows around the first transparent area 5, thereby achieving the purpose of changing the flow pattern of the airflow around the bridge structure and suppressing the vortex-induced vibration of the bridge. Optimally, the spacing between two adjacent first closed areas 6 is equal, that is, the number of railing units 8 in each of the first transparent areas 5 is the same, so that the aerodynamic force acting on the inspection railing 3 is evenly distributed. Furthermore, a plurality of equally spaced windshield strips 9 are provided between two adjacent first columns 4, and the windshield strips 9 are arranged parallel to the first columns 4. The provision of the windshield strips 9 can not only enhance the strength of the inspection railing 3, but also further change the flow pattern of the airflow around it.

[0029] Refine the structure of the roadway guardrail 2, such as Figure 3As shown, the upper steel guardrail of the carriageway guardrail 2 includes a plurality of second columns 11 arranged at equal intervals along the direction of the bridge, and the interval between two adjacent second columns 11 is generally 1.5 to 2 m. Optimally, the second columns 11 of the carriageway guardrail 2 on the same side of the bridge deck 1 can be arranged one-to-one with the first columns 4 of the maintenance railing 3. There is a guardrail unit 15 between each two adjacent second columns 11. The second transparent area 13 is composed of 3 to 6 guardrail units 15. The airflow acting on the periphery of the roadway guardrail 2 can flow through the second transparent area 13. In this embodiment, the second transparent area 13 is specifically composed of 3 guardrail units 15. The second closed area 12 is composed of a guardrail unit 15 and a closure member 14 that closes the guardrail unit 15. The closure member 14 can be a sealing plate. The airflow acting on the second closed area 12 is blocked by the closure member 14, so that it flows around to the second transparent area 13, thereby achieving the purpose of changing the flow pattern of the airflow around the roadway guardrail 2 and suppressing the vortex-induced vibration of the bridge. Optimally, the spacing between two adjacent second closed areas 12 is equal, that is, the number of guardrail units 15 in each of the second transparent areas 13 is the same, so that the aerodynamic force acting on the roadway guardrail 2 is evenly distributed. Furthermore, a plurality of cross beams 16 are connected between two adjacent second upright posts 11 . The cross beams 16 are arranged perpendicular to the second upright posts 11 . The provision of the cross beams 16 enhances the strength of the roadway guardrail 2 .

[0030] A wind tunnel test was conducted on a bridge with a special treatment on the appearance of the inspection railing and the roadway guardrail according to this embodiment and a bridge with a conventional inspection railing and the roadway guardrail not treated. The test process is the prior art and will not be repeated here. The test results are shown in FIG. Figure 4 As shown, Figure a shows the test results of conventional inspection railings and roadway guardrails without treatment, and Figure b shows the test results of the inspection railings and roadway guardrails with special treatment in this embodiment. The test results show that the amplitude of the vortex-induced vibration of the bridge is reduced from 375mm to 57.1mm by using the wind-resistant guardrail of the large-span bridge of this embodiment, and the effect is very obvious.

[0031] The above examples are merely illustrative of the present invention and do not constitute a limitation on the protection scope of the present invention. All designs that are the same or similar to the present invention fall within the protection scope of the present invention.

Claims

1. A wind-resistant guardrail for a long-span bridge, characterized in that: It includes maintenance railings arranged on both sides of the bridge deck, and roadway guardrails arranged on both sides of the roadway of the bridge deck; the maintenance railings include a first transparent area and a first closed area alternately arranged along the direction of the bridge, and the roadway guardrails include a second transparent area and a second closed area alternately arranged along the direction of the bridge, and the first closed area and the second closed area on the same side of the bridge deck are staggered.

2. The wind-resistant guardrail for a long-span bridge according to claim 1, characterized in that: The maintenance railing is a metal railing, including a plurality of first columns arranged at equal intervals along the direction of the bridge, with a railing unit between every two adjacent first columns, the first transparent area is composed of 3 to 6 railing units, and the first closed area is composed of a railing unit and a closing member that closes the railing unit.

3. The wind-resistant guardrail for a long-span bridge according to claim 2, characterized in that: A plurality of windshield strips arranged at equal intervals are provided between two adjacent first upright posts, and the windshield strips are arranged parallel to the first upright posts.

4. A wind-resistant guardrail for a long-span bridge as claimed in claim 1 or 2, characterized in that: The distances between two adjacent first closed areas are equal.

5. The wind-resistant guardrail for a long-span bridge according to claim 1, characterized in that: The roadway guardrail adopts a combined structure of a lower concrete guardrail and an upper steel guardrail.

6. The wind-resistant guardrail for a long-span bridge according to claim 5, characterized in that: The upper steel guardrail of the carriageway guardrail includes a plurality of second columns arranged at equal intervals along the direction of the bridge, with a guardrail unit between each two adjacent second columns, the second transparent area is composed of 3 to 6 guardrail units, and the second closed area is composed of a guardrail unit and two closing parts for closing the guardrail unit.

7. The wind-resistant guardrail for a long-span bridge according to claim 6, characterized in that: A plurality of cross beams are connected between two adjacent second columns at intervals, and the cross beams are arranged perpendicular to the second columns.

8. A wind-resistant guardrail for a long-span bridge as claimed in claim 1 or 6, characterized in that: The distances between two adjacent second closed areas are equal.

9. The wind-resistant guardrail for a long-span bridge according to claim 1, characterized in that: The first closed area and the second closed area on the same side of the bridge deck are arranged alternately in sequence.

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