Wind tunnel test device and method for suspension bridge segment model

Abstract

The present invention discloses a wind tunnel test device and method for a suspension bridge segment model, comprising a main beam elastic suspension system and a main cable system. The main beam elastic suspension system comprises a main beam segment model, end members, and a spring suspension device. The end members are respectively provided at both ends of the main beam segment model and are suspended in a wind tunnel by the end members and the elastic suspension device. The main cable system comprises main cable models arranged on both sides of the main beam segment model and a rotating device for providing main cable stiffness and damping. The two ends of the main cable model are respectively connected to the end members via the rotating device. The present invention simulates the lateral stiffness of the main cable through the rotating device and provides the vertical and torsional stiffness of the bridge through the spring suspension device, thereby achieving vertical and torsional movement of the main beam and lateral movement of the main cable, more realistically simulating the wind-induced vibration characteristics of the bridge and providing more realistic and reliable test data for the design of long-span suspension bridges.

Description

Technical Field

[0001] The invention relates to a wind tunnel test of a suspension bridge segment model, in particular to a wind tunnel test device and method for a suspension bridge segment model. Background Art

[0002] As transportation infrastructure construction gradually extends to mountainous and coastal areas, bridges, as the primary solution for crossing seas and rivers and overcoming obstacles, are increasingly being built with long-span bridges, and their spans are constantly increasing. Currently, suspension bridges are the predominant long-span bridge structure, with spans far exceeding those of ordinary bridges.

[0003] As the span of suspension bridges continues to increase, the required bearing capacity of suspension bridges is also increasing. The main cable, as the main load-bearing component of the suspension bridge, is also increasing in size. In order to meet navigation requirements, a suspension bridge with four main cables will be set up. These will undoubtedly affect the aerodynamic performance of the main beam section, especially in the middle of the main beam span. On the other hand, relevant studies have found that although the main cable has little effect on the aerodynamic performance of the bridge during small vibrations of the bridge, the main cable will generate a large aerodynamic force during large vibrations of the bridge, thereby affecting the wind-induced vibration performance of the bridge. Therefore, the influence of the main cable needs to be considered in the study of the wind resistance of the suspension bridge. However, the influence of the main cable is rarely considered in the current study of the wind resistance of the suspension bridge, and the development of experimental research methods and experimental equipment is relatively lagging behind. For example:

[0004] Chinese patent publication number CN213068131U discloses an elastic suspension system for wind tunnel experiments on bridge segment models. This system provides bridge stiffness by setting up three sets of springs, but it still only considers the vertical and torsional stiffness of the main beam and cannot consider the influence of the main cable.

[0005] A Chinese patent publication number CN117433742A discloses a wind tunnel test device for a bridge segment model with magnetic levitation suspension. The magnetic levitation suspension support device allows the segment model to vibrate in mid-air, but only the main beam section can be considered.

[0006] Chinese patent publication number CN117516858A discloses a wind tunnel test device for the girder erection stage of suspension bridge construction. Although the device discloses a main cable structure, this solution is only applicable to wind tunnel tests during the bridge construction stage. Due to the lack of components such as bridge towers and supports, wind tunnel tests of the bridge in its completed state cannot be carried out. Summary of the Invention

[0007] The technical problem to be solved by the present invention is: in order to meet the demand of considering the influence of the main cable in the wind resistance research of suspension bridges, the present invention provides a wind tunnel test device for a suspension bridge segment model. In the wind tunnel test, the stiffness and aerodynamic shape of the main cable can be considered to realize large-scale vertical and torsional movement of the bridge segment model and movement of the main cable, thereby more realistically simulating the wind-induced vibration characteristics of the bridge and providing more realistic and reliable test data for the design of long-span suspension bridges.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0009] A wind tunnel test device for a suspension bridge segment model includes a main beam elastic suspension system, the main beam elastic suspension system comprising a main beam segment model, end members, and a spring suspension device. The main beam segment model is provided with the end members at both ends and is suspended in a wind tunnel by the end members and the elastic suspension device. The structural features of the device are as follows:

[0010] It also includes a main cable system, which includes main cable models arranged on both sides of the main beam segment model and a rotating device for providing main cable stiffness and damping, and the two ends of the main cable model are respectively connected to the end members via the rotating device.

[0011] The present invention adds a main cable system to the wind tunnel test device of the suspension bridge segment model. The main cable model in the main cable system simulates the actual main cable shape according to the geometric scale ratio. The rotating device provides the main cable stiffness and damping. At the same time, the main cable model is connected to the main beam segment model through the rotating device, thereby allowing the main cable model to rotate around the rotating bearing, simulating the movement mode of the main cable rotating around the main beam suspension point on an actual bridge. In this way, in the wind tunnel test, the stiffness and aerodynamic shape of the main cable can be taken into account, and large-scale vertical and torsional movement of the bridge segment model and the main cable movement can be achieved. The wind-induced vibration characteristics of the bridge can be simulated more realistically, providing more realistic and reliable test data for the design of long-span suspension bridges.

[0012] Preferably, the rotating device comprises a rigid rod and a rotating bearing, one end of the rigid rod is connected to the main cable model, and the other end is connected to the rotating bearing, and the rotating bearing is installed on the end member.

[0013] Preferably, a second spring is mounted between the rigid rod and the end member.

[0014] Preferably, the rotating device further comprises a fixing plate, wherein the fixing plate is fixedly connected to the end member, and one end of the second spring is connected to the fixing plate, and the other end is connected to the rigid rod.

[0015] Preferably, a plurality of second spring connection points are provided on the fixing plate.

[0016] Preferably, the end member includes an end plate, an end shaft and a rigid end rod, the end plate is fixed to the end of the main beam segment model, one end of the end shaft is connected to the end plate, and the other end is connected to the end rod, and the two ends of the end rod are respectively connected to the elastic suspension device.

[0017] Preferably, the elastic suspension device includes at least eight first springs distributed at the four corners of the main beam segment model, the first springs are vertically installed in the wind tunnel, and one end of the first spring is fixedly connected to the inner wall of the wind tunnel, and the other end is fixed to the end rod.

[0018] Based on the same inventive concept, the present invention also provides a method for conducting a wind tunnel test using the suspension bridge segment model wind tunnel test device, wherein:

[0019] The main beam segment model simulates the aerodynamic shape of the main beam in strict accordance with the geometric scale ratio, reflecting the aerodynamic performance of the main beam;

[0020] The spring suspension device suspends the main beam segment model through the end member and the first spring, so as to simulate the stiffness and damping characteristics of the bridge, and provides vertical and torsional stiffness for the main beam segment model, allowing the main beam segment model to vibrate vertically and torsionally;

[0021] The main cable model simulates the actual main cable shape according to the geometric scale ratio;

[0022] The rotating device is used to connect the end member of the main cable model and the main beam segment model, and provides main cable stiffness and damping through its movement relative to the main beam segment model;

[0023] The main cable model is connected to the rotation bearing installed on the end member through a rigid rod, allowing the main cable model to rotate around the rotation bearing, simulating the movement of the main cable on an actual bridge connected to the main beam through a hanger rod and rotating around the main beam hanging point;

[0024] The rigid rod is connected to the end member via a second spring, thereby increasing the rigidity of the main cable model. The rigidity of the main cable model can be adjusted by changing the size and installation position of the second spring.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The wind tunnel test device for suspension bridge segment models provided by the present invention simulates the lateral stiffness of the main cable through a rotating device and provides the vertical and torsional stiffness of the bridge through a spring suspension device, thereby realizing the vertical and torsional movement of the main beam and the lateral movement of the main cable. It can more realistically simulate the wind-induced vibration characteristics of the bridge (including the movement process and aerodynamic influence of the main cable during large-scale vibration of the bridge), providing more realistic and reliable test data for the design of long-span suspension bridges.

[0027] 2. The main cable model of the present invention can be resized and is suitable for wind tunnel testing of suspension bridges with different structural parameters;

[0028] 3. The end components of the main cable system and the main beam elastic suspension system of the present invention are detachable and easy to disassemble and install. They are applicable to any main beam segment model. When other main beam segment models are used for testing, there is no need to make a separate main cable system, thereby reducing the testing cost.

[0029] 4. The present invention adopts a main beam segment model, which can be set to the structural parameters of the bridge in the completed state or the construction state. The aerodynamic shape of the completed state can also be easily changed to the construction state, so that the solution of the present invention is applicable to both the completed state and the construction state of the bridge, and has a wider applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 Schematic diagram of the structure of the device of the present invention.

[0032] Figure 2 Schematic diagram of the main cable system.

[0033] Figure 3 A side view of the main cable system.

[0034] In the picture:

[0035] Elastic suspension system 1; main beam segment model 101; end plate 102; end shaft 103; rigid end rod 104; first spring 105;

[0036] Main cable system 2; main cable model 201; rigid rod 202; rotation bearing 203; fixing plate 204; bolt 205; second spring 206; second spring 207; fixed end 208; bolt hole 209. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with specific preferred embodiments, but the scope of protection of the present invention is not limited thereby.

[0038] In the description of the present invention, it should be noted that the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0040] See also Figure 1 - Figure 3 An embodiment of a wind tunnel test device for a suspension bridge segment model of the present invention includes a main beam elastic suspension system 1 and a main cable system 2.

[0041] The main beam elastic suspension system 1 includes a main beam segment model 101, end components, and a spring suspension device. The main beam segment model 101 is a rigid structure and simulates the aerodynamic shape of the main beam in strict accordance with the geometric scale ratio, which can largely reflect the aerodynamic performance of the main beam. The end components include end plates 102, end shafts 103, and rigid end rods 104. The end plates 102 are fixed to the two ends of the main beam segment model 101 through one end of the end shaft 103 to ensure the stability of the additional flow field of the main beam segment model 101. The rigid end rods 104 are fixed to the other end of the end shaft 103. The spring suspension device mainly consists of eight first springs 105 distributed at the four corners of the main beam segment model 101. The first springs 105 are vertically installed in the wind tunnel, and one end of the first spring 105 is fixedly connected to the inner wall (top or bottom) of the wind tunnel, and the other end is fixed to the end rod 104. The first spring 105 is connected to the end rod 104 and is used to provide vertical and torsional stiffness to the rigid main beam segment model 101, allowing the bridge to vibrate vertically and torsionally.

[0042] The main cable system 2 includes a main cable model 201 and a rotation device. The main cable model 201 simulates the shape of an actual main cable at a geometric scale and is arranged in parallel on both sides of the main beam segment model 101. The rotation device includes a rigid rod 202, a rotation bearing 203, a fixing plate 204, a bolt 205, a second spring 206, a second spring 207, a fixed end 208, and a bolt hole 209. The main cable model 201 is connected to the rotation bearing 203 via the rigid rod 202, allowing the main cable model 201 to rotate around the rotation bearing 203, simulating the movement of a main cable on a real bridge connected to the main beam via a hanger rod and rotating around the main beam suspension point. The fixing plate 204 is detachably mounted to the end plate 102 of the end member via bolts 205, and the rotation bearing 203 is mounted on the fixing plate 204. The second spring 206 and the second spring 207 are installed between the fixing plate 204 and the rigid rod 202.

[0043] The second spring 206 and the second spring 207 are used to increase the stiffness of the main cable model 201, and a plurality of bolt holes 209 are provided on the fixing plate 204. The fixed ends 208 of the second spring 206 and the second spring 207 adjust the stiffness of the main cable model 201 by connecting with different bolt holes 209 and changing their own sizes.

[0044] The wind tunnel test device for a suspension bridge segment model with a main cable provided by the present invention simulates the lateral stiffness of the main cable through a rotating device, provides the vertical and torsional stiffness of the bridge through a spring suspension device, realizes the vertical and torsional movement of the main beam and the lateral movement of the main cable, more realistically simulates the wind-induced vibration characteristics of the bridge, and provides more realistic and reliable test data for the design of long-span suspension bridges.

[0045] Application Case 1

[0046] The main beam segment model 101 is connected to four first springs 105 through end components such as end plates 102, end shafts 103 and rigid end rods 104. The main beam segment model 101 is suspended in the wind tunnel through the first springs 105, and vertical and torsional stiffness are provided to the main beam segment model 101; the main cable system 2 is fixed to the end plate 102 through a fixing plate 204 and bolts 205, and the main cable model 201 is connected to the rotating bearing 203 through a rigid rod 202, allowing the main cable model 201 to rotate around the rotating bearing 203; the second springs 206 and 207 in the main cable system 2 are connected to the rigid rod 202 and the fixing plate 204 to increase the stiffness of the main cable model 201. The main cable stiffness is adjusted by changing the size of the second springs 206 and 207 and the connection position of the second springs 206 and 207 and the fixing plate 204.

[0047] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make many possible changes and modifications to the technical solution of the present invention using the technical content disclosed above, or modify it into an equivalent embodiment with equivalent changes. Therefore, any simple modification, equivalent change, and modification made to the above embodiment in accordance with the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A wind tunnel test apparatus for a suspension bridge segment model, comprising a main beam elastic suspension system, the main beam elastic suspension system comprising a main beam segment model, end members, and a spring suspension device. The main beam segment model is provided with the end members at both ends and is suspended in a wind tunnel by the end members and the elastic suspension device. The apparatus is characterized by: It also includes a main cable system, which includes main cable models arranged on both sides of the main beam segment model and a rotating device for providing main cable stiffness and damping, and the two ends of the main cable model are respectively connected to the end members via the rotating device.

2. The suspension bridge segment model wind tunnel test device according to claim 1, characterized in that: The rotating device includes a rigid rod and a rotating bearing. One end of the rigid rod is connected to the main cable model, and the other end is connected to the rotating bearing. The rotating bearing is installed on the end member.

3. The suspension bridge segment model wind tunnel test device according to claim 2, characterized in that: A second spring is mounted between the rigid rod and the end member.

4. The suspension bridge segment model wind tunnel test device according to claim 3, characterized in that: The rotating device further includes a fixing plate fixedly connected to the end member, one end of the second spring is connected to the fixing plate, and the other end is connected to the rigid rod.

5. The suspension bridge segment model wind tunnel test device according to claim 4, characterized in that: A plurality of second spring connection points are arranged on the fixing plate.

6. The suspension bridge segment model wind tunnel test device according to claim 1, characterized in that: The end member includes an end plate, an end shaft and an end rod. The end plate is fixed to the end of the main beam segment model. One end of the end shaft is connected to the end plate, and the other end is connected to the end rod. Both ends of the end rod are respectively connected to the elastic suspension device.

7. The suspension bridge segment model wind tunnel test device according to claim 6, characterized in that: The elastic suspension device includes at least eight first springs distributed at the four corners of the main beam segment model. The first springs are connected in series in pairs and vertically installed in the wind tunnel, and one end of the first spring is fixedly connected to the inner wall of the wind tunnel, and the other end is fixedly connected to the end rod.

8. A method for conducting a wind tunnel test using the suspension bridge segment model wind tunnel test apparatus according to any one of claims 1 to 7, characterized in that: The main beam segment model simulates the aerodynamic shape of the main beam in strict accordance with the geometric scale ratio, reflecting the aerodynamic performance of the main beam; The spring suspension device suspends the main beam segment model through the end member and the first spring, so as to simulate the stiffness and damping characteristics of the bridge, and provides vertical and torsional stiffness for the main beam segment model, allowing the main beam segment model to vibrate vertically and torsionally; The main cable model simulates the actual main cable shape according to the geometric scale ratio; The rotating device is used to connect the end member of the main cable model and the main beam segment model, and provides main cable stiffness and damping through its movement relative to the main beam segment model; The main cable model is connected to the rotation bearing installed on the end member through a rigid rod, allowing the main cable model to rotate around the rotation bearing, simulating the movement of the main cable on an actual bridge connected to the main beam through a hanger rod and rotating around the main beam hanging point; The rigid rod is connected to the end member via a second spring, thereby increasing the rigidity of the main cable model. The rigidity of the main cable model can be adjusted by changing the size and installation position of the second spring.

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