Streamlined box girder wind tunnel test model and adjusting method

Abstract

This invention provides a streamlined box girder wind tunnel test model and adjustment method, belonging to the field of wind tunnel testing technology. The model includes a box girder body, a bridge deck railing assembly, and a track assembly. The box girder body has a streamlined closed box girder cross-section structure, with its top surface being the bridge deck and its bottom surface being the girder bottom. The bridge deck railing assembly is installed on the bridge deck, and its railing posts are connected to the box girder body through a first adjustment mechanism, allowing adjustment of lateral position and tilt angle. The track assembly is installed at the bottom of the girder and is connected to the box girder body through a second adjustment mechanism, allowing adjustment of lateral position. This invention integrates railing position adjustment, railing angle adjustment, and track position adjustment into a single model, enabling independent adjustment of multiple parameters within a single model. This eliminates the need to create multiple models for different parameter combinations, reducing testing costs and time, and ensuring the comparability of a series of test data.

Description

Technical Field

[0001] This invention belongs to the field of wind tunnel testing technology, and more specifically, relates to a streamlined box girder wind tunnel testing model and adjustment method. Background Technology

[0002] In bridge wind-resistant design, wind tunnel testing is the core method for verifying the aerodynamic stability of the structure. Among these methods, segmental model testing is widely used due to its cost-effectiveness and flexible parameter adjustment. Streamlined box girders are one of the most common cross-sectional forms in long-span bridges. Their excellent aerodynamic shape can be compromised in completed bridge segments due to the installation of ancillary facilities such as railings and maintenance vehicle tracks. Existing research indicates that bridge deck maintenance walkway railings are the primary sensitive components to vortex-induced vibration, and changes in the position of the maintenance vehicle tracks also significantly affect the vortex-induced vibration response. Therefore, studying the influence of railing position, railing angle, and maintenance vehicle track position on the aerodynamic performance of box girders in wind tunnel testing is a crucial step in wind-resistant optimization design.

[0003] Currently, the segmental models used in wind tunnel tests are mostly fixed models customized for specific parameter combinations. This means that the positions and angles of the guardrails and the position of the maintenance vehicle track are determined during model fabrication and cannot be changed during testing. While some models have adjustment functions, these typically only apply to a single parameter (e.g., only the guardrail angle or the position of a single component is adjustable), and the adjustment methods often rely on manual disassembly and reassembly, which is cumbersome and has limited accuracy. When it is necessary to examine the coupled effects of multiple parameters, researchers often need to fabricate multiple models or repeatedly modify existing models, resulting in long development cycles, high costs, and difficulty in ensuring comparability between different operating conditions. Summary of the Invention

[0004] The purpose of this invention is to provide a streamlined box girder wind tunnel test model and adjustment method, aiming to solve the technical problems of existing streamlined box girder wind tunnel test models lacking the integration of railing position adjustment, railing angle adjustment and maintenance vehicle track position adjustment on the same model, resulting in the need to make multiple sets of models for different parameter combinations, high test costs, long cycles and poor data comparability.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a streamlined box girder wind tunnel test model, comprising: The main body of the box girder is a streamlined closed box girder cross-section structure, with its top surface being the bridge deck and its bottom surface being the girder bottom. A bridge deck railing assembly is installed on the bridge deck of the main body of the box girder, including railing posts and railing beams. The railing posts are connected to the main body of the box girder through a first adjustment mechanism. The bridge deck railing assembly adjusts its lateral position and tilt angle with the help of the first adjustment mechanism. The track main body assembly is disposed at the bottom of the box girder main body. The track main body assembly is connected to the box girder main body through a second adjustment mechanism, and the track main body assembly adjusts its lateral position by means of the second adjustment mechanism.

[0006] In one possible implementation, the first adjusting mechanism includes: The first chute is provided on the main bridge deck of the box girder and extends laterally along the bridge deck; The first sliding connector is slidably connected within the first groove; An angle-adjusting pivot is connected at one end to the first sliding connector and at the other end to the lower end of the railing post. The railing post can rotate relative to the first sliding connector around the angle-adjusting pivot and be positioned at any angle by a locking member to adjust the tilt angle of the bridge deck railing assembly. The bridge deck railing assembly can adjust its lateral position by means of the sliding energy of the first sliding connector. A first position indicator scale is set next to the first slide groove to indicate the position of the first sliding connector; An angle indicator scale is set at the angle adjustment pivot to indicate the tilt angle of the railing post.

[0007] In one possible implementation, the first regulating mechanism further includes: The railing drive unit is located inside the box girder body and its power output end passes through the box girder body and is connected to the first sliding connector. The railing drive unit is used to drive the first sliding connector to slide in the first groove.

[0008] In one possible implementation, the second regulating mechanism includes: The second chute is provided on the bottom of the main beam of the box girder and extends laterally along the bottom of the beam. The second sliding connector is slidably connected within the second slide groove and can be positioned at any position to adjust the lateral position of the track main body assembly; The second position indicator scale is located next to the second slide groove and is used to indicate the position of the second sliding connector.

[0009] In one possible implementation, the second regulating mechanism further includes: The track drive unit is located inside the box girder body and its power output end passes through the box girder body and is connected to the second sliding connector. The track drive unit is used to drive the second sliding connector to slide in the second groove.

[0010] In one possible implementation, the railing post is provided with a height adjustment structure, and the railing beam is slidably connected to the railing post through the height adjustment structure to adjust the height of the railing beam relative to the bridge deck.

[0011] In one possible implementation, the first regulating mechanism and the second regulating mechanism are each electrically connected to a control unit, which is used to control the operation of the first regulating mechanism and the second regulating mechanism.

[0012] In one possible implementation, a cavity is formed in the main body of the box girder adjacent to the first sliding groove. An elongated through hole is formed on the inner sidewall of the first sliding groove, and the elongated through hole communicates with the cavity. Multiple baffles are arranged in the cavity along the transverse direction of the main body of the box girder and are used to cover the first sliding groove. The multiple baffles pass through the elongated through hole and can slide along the width direction of the first sliding groove to form a covered state covering the first sliding groove and an open state opening the first sliding groove. At least one of the baffles is arranged to avoid the first sliding connector.

[0013] In one possible implementation, a pusher for pushing the baffle plate to slide is provided inside the cavity.

[0014] The beneficial effects of the streamlined box girder wind tunnel test model provided by this invention are as follows: Compared with the prior art, the adjustment of the railing position, the adjustment of the railing angle and the adjustment of the maintenance vehicle track position are integrated into the same wind tunnel test model. Researchers only need to make one model to complete a series of tests with multiple parameters and multiple combinations. There is no need to make a new model for each parameter combination, which greatly reduces the model making cost and time cycle.

[0015] The three parameters—the lateral position of the railing, the tilt angle of the railing, and the lateral position of the maintenance vehicle track—are each independently adjustable and do not interfere with each other. Different parameter configurations can be freely combined according to the needs of the experiment to systematically study the independent and coupled effects of each parameter on the aerodynamic performance of the box girder.

[0016] All adjustments were performed on the same model, avoiding deviations in experimental data caused by manufacturing errors between different models, and ensuring the consistency and comparability of data from a series of experiments.

[0017] The first and second adjustment mechanisms are integrated into the bridge deck and bottom of the box girder body, reducing interference with the aerodynamic shape of the model itself and ensuring the accuracy of wind tunnel test results.

[0018] This invention also provides a method for adjusting a streamlined box girder wind tunnel test model, comprising the following steps: S1: Determine the lateral position parameters of the bridge deck railing assembly, the tilt angle of the bridge deck railing assembly, and the lateral position parameters of the main track assembly according to the wind tunnel test plan; S2: Use the first adjustment mechanism to adjust the position of the bridge deck railing assembly, move it to the target position and adjust it to the target angle, and then lock it; S3: Use the second adjustment mechanism to adjust the position of the main track assembly and move it to the target position, then lock it; S4: Place the adjusted streamlined box girder wind tunnel test model in the wind tunnel for aerodynamic performance testing; S5: Repeat steps S1 to S4, and conduct a series of wind tunnel tests under different parameter combinations of bridge deck railing component positions, bridge deck railing component angles, and track main component positions to obtain aerodynamic performance data under different parameter combinations. The adjustment method for a streamlined box girder wind tunnel test model provided by this invention has the same beneficial effects as the aforementioned streamlined box girder wind tunnel test model, and will not be repeated here. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of a streamlined box girder wind tunnel test model provided in an embodiment of the present invention; Figure 2 for Figure 1 Enlarged view of some of the structures in the image; Figure 3 for Figure 1 or Figure 2 A partial structural diagram of the bridge deck railing assembly; Figure 4 for Figure 1 or Figure 2 A structural schematic diagram of the beam bottom and the main track components; Figure 5 for Figure 4 Enlarged view of the middle section structure; Figure 6 for Figure 5 Another implementation diagram; Figure 7 for Figure 1 Schematic diagram of the left-middle end structure.

[0021] Explanation of reference numerals in the attached figures: 1. Box girder main body; 11. Long strip through hole; 12. Baffle plate; 13. Pusher; 2. Bridge deck railing assembly; 21. Railing post; 22. Railing beam; 23. Height adjustment structure; 3. Track main assembly; 4. First adjustment mechanism; 41. First slide groove; 42. First sliding connector; 43. Angle adjustment shaft; 44. First position indicator scale; 45. Angle indicator scale; 46. Railing drive unit; 5. Second adjustment mechanism; 51. Second slide groove; 52. Second sliding connector; 53. Second position indicator scale; 54. Track drive unit; 6. Support roller; 7. Frame; 8. Control unit. Detailed Implementation

[0022] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0024] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0025] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0026] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0027] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0028] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0029] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0030] Currently, in wind tunnel tests, the position and angle of the railings and the position of the maintenance vehicle track have a significant impact on the aerodynamic performance of the box girder. However, existing segmental models lack adjustment mechanisms that integrate these three factors into the same model. Usually, multiple models need to be made for different parameter combinations, which is costly, time-consuming, and results in poor data comparability.

[0031] To address the aforementioned technical problems, this invention provides a streamlined box girder wind tunnel test model that integrates railing position adjustment, railing angle adjustment, and maintenance vehicle track position adjustment into a single unit, aiming to achieve independent and precise adjustment of multiple parameters on a single model.

[0032] Please refer to the following: Figures 1 to 2 The following is a detailed description of a streamlined box girder wind tunnel test model provided in this application, with reference to the accompanying drawings. A streamlined box girder wind tunnel test model includes a box girder body 1, a bridge deck railing assembly 2, and a track body assembly 3.

[0033] The main body of the box girder 1 is a streamlined closed box girder cross-section structure, with its top surface being the bridge deck and its bottom surface being the girder bottom. The main body of the box girder 1 is manufactured according to the scale of the actual bridge (such as 1:30, 1:40, 1:50), and the material can be metal (such as stainless steel, aluminum alloy), wood, or photosensitive resin 3D printing material, to ensure that the model has sufficient rigidity and dimensional stability, while also facilitating the processing of structures such as grooves on its surface.

[0034] The bridge deck railing assembly 2 is installed on the bridge deck of the box girder body 1, near both sides, and includes railing posts 21 and railing beams 22. The railing posts 21 are connected to the box girder body 1 through a first adjustment mechanism 4. The bridge deck railing assembly 2 can be adjusted in lateral position and tilt angle by means of the first adjustment mechanism 4. The railing posts 21 are vertically arranged, and the railing beams 22 are horizontally connected to the sides of the railing posts 21, located between two adjacent railing posts 21. That is, the railing beams 22 do not contact the bridge deck. The two ends of the railing beams 22 are fixedly connected to two adjacent railing posts 21 respectively, forming an integral structure.

[0035] The track main body component 3 is located at the bottom of the box girder main body 1. The track main body component 3 is connected to the box girder main body 1 through the second adjustment mechanism 5. The track main body component 3 adjusts its lateral position with the help of the second adjustment mechanism 5.

[0036] The present invention provides a streamlined box girder wind tunnel test model, which, compared with the prior art, integrates the adjustment of the railing position, the adjustment of the railing angle, and the adjustment of the maintenance vehicle track position on the same wind tunnel test model. Researchers only need to make one model to complete a series of tests with multiple parameters and combinations, without having to make a new model for each parameter combination, which greatly reduces the model making cost and time cycle.

[0037] The three parameters—the lateral position of the railing, the tilt angle of the railing, and the lateral position of the maintenance vehicle track—are each independently adjustable and do not interfere with each other. Different parameter configurations can be freely combined according to the needs of the experiment to systematically study the independent and coupled effects of each parameter on the aerodynamic performance of the box girder.

[0038] All adjustments were made on the same model, avoiding deviations in experimental data caused by manufacturing errors between different models, and ensuring the consistency and comparability of data from a series of experiments.

[0039] The first adjustment mechanism 4 and the second adjustment mechanism 5 are integrated into the bridge deck and bottom of the box girder body 1 to reduce interference with the aerodynamic shape of the model itself and ensure the accuracy of the wind tunnel test results.

[0040] In some embodiments, please refer to Figures 1 to 2 The first adjustment mechanism 4 includes a first slide groove 41, a first sliding connector 42, an angle adjustment shaft 43, a first position indicator scale 44, and an angle indicator scale 45.

[0041] The first sliding groove 41 is provided on the bridge deck of the box girder body 1 and extends laterally along the bridge deck; the first sliding connector 42 is slidably connected to the first sliding groove 41; one end of the angle adjusting shaft 43 is connected to the first sliding connector 42 and the other end is connected to the lower end of the railing post 21. The railing post 21 can rotate relative to the first sliding connector 42 around the angle adjusting shaft 43 and be positioned at any angle by a locking device (existing technology, such as a locking nut) to adjust the tilt angle of the bridge deck railing assembly 2. The bridge deck railing assembly 2 can adjust its lateral position by means of the sliding of the first sliding connector 42; the first position indicator scale 44 is provided on the side of the first sliding groove 41 to indicate the position of the first sliding connector 42; the angle indicator scale 45 is provided at the angle adjusting shaft 43 to indicate the tilt angle of the railing post 21. There are multiple first sliding grooves 41, which are arranged at intervals along the length of the box girder body 1. There are multiple railing posts 21, each corresponding to a multiple first sliding grooves 41. The bridge deck railing assembly 2 includes multiple railing posts 21 and multiple railing beams 22. There are four sets of bridge deck railing assemblies 2, with each pair of sets located near the two sides of the box girder body 1.

[0042] Specifically, the first groove 41 is an elongated groove structure, and its cross-sectional shape can be a T-groove, a dovetail groove, or a rectangular groove, used to provide linear sliding guidance for the first sliding connector 42. Preferably, the first groove 41 adopts a T-groove structure to prevent the first sliding connector 42 from coming out of the groove opening when subjected to vertical tension.

[0043] By using a locking element, the angle of the railing post 21 after rotation can be fixed by passing through the angle adjustment shaft 43. The angle adjustment shaft 43 is a hinge or similar material found in the prior art, which allows the railing post 21 to swing or rotate to adjust its tilt angle. The tilt angle referred to in this invention is the angle between the railing post 21 and the bridge deck. With the above structure, the bridge deck railing assembly 2 can slide along the first slide groove 41 via the first sliding connector 42 to adjust its lateral position, and at the same time, it can adjust its tilt angle by rotating the railing post 21 around the angle adjustment shaft 43. The lateral position adjustment and the tilt angle adjustment are independent of each other and do not interfere with each other.

[0044] Specifically, the first position indicator scale 44 is a scale line arranged along the length of the first slide groove 41. The operator can accurately know the current lateral position parameters by reading the scale value corresponding to the first sliding connector 42.

[0045] The angle indicator scale 45 is an angle scale dial set on the angle adjustment shaft 43. The operator can accurately know the current tilt angle parameter by reading the angle scale value corresponding to the railing post 21.

[0046] By using the combination of the first position indicator scale 44 and the angle indicator scale 45, the operator can accurately record the position and angle parameters after each adjustment, ensuring that the same working condition can be accurately reproduced in different test batches.

[0047] Optionally, limiting members (existing technology) are provided at both ends of the first slide groove 41 to limit the sliding range of the first sliding connector 42 and prevent the first sliding connector 42 from sliding out of the first slide groove 41.

[0048] Optionally, a dust cover (not shown in the figure) is provided at the opening of the first slide groove 41 to cover the opening of the first slide groove 41 in the non-adjusted state, so as to prevent dust or debris from falling into the slide groove and affecting the sliding accuracy.

[0049] In some embodiments, please refer to Figures 1 to 2 The first adjustment mechanism 4 also includes a railing drive unit 46. The railing drive unit 46 is placed inside the box girder body 1 and its power output end passes through the box girder body 1 and is connected to the first sliding connector 42. The railing drive unit 46 is used to drive the first sliding connector 42 to slide in the first slide groove 41 to realize the automatic adjustment of the lateral position of the bridge deck railing assembly 2.

[0050] Specifically, the railing drive unit 46 is a linear drive module, which can be any of the following: a micro stepper motor with a lead screw and nut mechanism, a micro servo motor with a gear and rack mechanism, or an electric push rod. In this embodiment, the railing drive unit 46 is preferably an electric push rod, which is fixedly installed inside the box girder body 1. One end is fixedly connected to the box girder body 1, and the other end passes through the side wall of the first groove and connects to the first sliding connector 42, thereby driving the first sliding connector 42 to slide along the first slide groove 41.

[0051] like Figure 1 and Figure 7 As shown, the wiring harness connected to the electric push rod passes through the inside of the box girder body 1 and is led out from the side of the box girder body 1. Support rollers 6 and frames 7 are respectively set at both ends of the box girder body 1. One end of the support roller 6 is fixedly connected to the end of the box girder body 1, and the frame 7 is used to support the support roller 6. A control panel is set at the other end of the support roller 6. The wiring harness passes through the inside of the support roller 6 and is electrically connected to the control panel. Thus, the operator can control the railing drive unit 46 by operating it on the control panel during wind tunnel operation, and realize the online dynamic adjustment of the lateral position of the bridge deck railing assembly 2.

[0052] By setting up the guardrail drive unit 46, operators do not need to disassemble or manually operate the model each time they make adjustments. This is especially suitable for working conditions where the guardrail position needs to be changed multiple times during wind tunnel operation to capture changes in aerodynamic response, which greatly improves test efficiency and safety.

[0053] In some embodiments, please refer to Figures 4 to 5 The second adjustment mechanism 5 includes a second slide groove 51, a second sliding connector 52, and a second position indicator scale 53. The second slide groove 51 is disposed on the bottom of the box girder body 1 and extends laterally along the bottom of the beam; the second sliding connector 52 is slidably connected within the second slide groove 51 and can be positioned at any position to adjust the lateral position of the track body assembly 3; the second position indicator scale 53 is disposed beside the second slide groove 51 and is used to indicate the position of the second sliding connector 52. The structure of the second slide groove 51 is the same as that of the first slide groove 41, and will not be described again here. It is used to provide linear sliding guidance for the second sliding connector 52. There are multiple second slide grooves 51 and they are spaced apart along the length of the box girder body 1. There are two sets of track body assemblies 3, both of which are connected to the second adjustment mechanism 5.

[0054] When the second sliding connector 52 slides along the second slide groove 51, the track body moves accordingly, thereby adjusting the lateral position of the track body assembly 3. The second position indicator scale 53 is a scale line arranged along the length of the second slide groove 51. The operator can accurately obtain the current lateral position parameters of the track body assembly 3 by reading the scale value corresponding to the second sliding connector 52. Through the second position indicator scale 53, the operator can accurately record the track position parameters after each adjustment, ensuring that the same working condition can be accurately reproduced in different test batches.

[0055] The sliding direction of the second sliding connector 52 is parallel to the sliding direction of the first sliding connector 42, so that the bridge railing assembly 2 and the track main body assembly 3 can be adjusted in position along the same transverse coordinate system, which facilitates the establishment of the correspondence between the position changes of the two components and the aerodynamic performance in the analysis of test results.

[0056] Limiting elements are provided at both ends of the second slide groove 51 to limit the sliding range of the second sliding connector 52, prevent the second sliding connector 52 from sliding out of the second slide groove 51, and prevent the track main body assembly 3 from colliding with other parts of the box girder main body 1 during the adjustment process.

[0057] Preferably, a dust cover (not shown in the figure) is provided at the opening of the second slide groove 51 to cover the opening of the second slide groove 51 in the non-adjusted state, so as to prevent dust or debris from falling into the slide groove and affecting the sliding accuracy.

[0058] In some embodiments, please refer to Figures 4 to 5The second adjustment mechanism 5 also includes a track drive unit 54. The track drive unit 54 is located inside the box girder body 1, and its power output end passes through the box girder body 1 and is connected to the second sliding connector 52. The track drive unit 54 is used to drive the second sliding connector 52 to slide within the second slide groove 51. The track drive unit 54 has the same structure as the guardrail drive unit 46 mentioned above, and will not be described again here. The wiring harness connected to the track drive unit 54 passes through the box girder body 1 and is led out and electrically connected to the control panel. The operator can remotely control the online dynamic adjustment of the lateral position of the track body component 3 through the external control panel during wind tunnel operation, realizing coordinated operation with the guardrail position adjustment.

[0059] The track drive unit 54 is located in the cavity of the box girder body 1 adjacent to the second slide groove 51. One end is fixedly connected to the box girder body 1, and the other end is connected to the second sliding connector 52. The position of the second sliding connector 52 can be adjusted by its extension and retraction adjustment.

[0060] In some embodiments, please refer to Figure 3 A height adjustment structure 23 is provided on the railing post 21. The railing beam 22 is slidably connected to the railing post 21 through the height adjustment structure 23 to adjust the height of the railing beam 22 relative to the bridge deck. Specifically, the height adjustment structure 23 includes an adjustment groove arranged along the height direction of the railing post 21 and a connecting slider that slides within the adjustment groove. The end of the railing beam 22 is fixedly connected to the connecting slider, which can slide up and down along the adjustment groove, thereby driving the railing beam 22 to rise and fall relative to the bridge deck.

[0061] Specifically, a locking bolt is provided on the connecting slider. When the railing beam 22 slides to the target height, the connecting slider is fixed in the current position in the adjusting groove by tightening the locking bolt, thereby achieving the height positioning of the railing beam 22.

[0062] Preferably, the adjusting groove is a T-groove structure, and the connecting slider is a T-shaped slider adapted to the T-groove, so as to prevent the connecting slider from coming out of the adjusting groove when subjected to outward pulling force, thereby improving the connection reliability.

[0063] Preferably, a height indicator scale is provided next to the adjusting slide to indicate the current position of the connecting slider, that is, the current height value of the railing beam 22 relative to the bridge deck. Through the height indicator scale, the operator can accurately record the height parameters after each adjustment to ensure that the same height condition can be accurately reproduced in different test batches.

[0064] Limiting parts are provided at both ends of the adjusting slide to limit the sliding range of the connecting slider and prevent the railing beam 22 from coming off the upper end of the railing post 21 or hitting the lower end structure during the adjustment process.

[0065] By setting the height adjustment structure 23, the streamlined box girder wind tunnel test model of this embodiment further realizes the independent adjustment of the railing height. That is, it integrates the independent adjustment functions of four parameters, namely the railing lateral position, railing tilt angle, railing height and track lateral position, on the same model, which further expands the research dimensions and applicable scope of the model.

[0066] In some embodiments, please refer to Figure 1 The first adjusting mechanism 4 and the second adjusting mechanism 5 are electrically connected to a control unit 8, which is used to control the operation of the first adjusting mechanism 4 and the second adjusting mechanism 5. The control unit 8 is the control panel mentioned above, which can control the operation of the railing drive unit 46 of the first adjusting mechanism 4 and the track drive unit 54 of the second adjusting mechanism 5, thereby realizing the adjustment of the railing lateral position and the track lateral position.

[0067] To seal the openings of the first slide 41 and the second slide 51 and prevent dust, debris, and other impurities from entering the slides during wind tunnel testing and affecting sliding accuracy and test results, in some embodiments, please refer to [the relevant documentation / reference needed]. Figures 5 to 6 A cavity is formed inside the box girder body 1 adjacent to the first sliding groove 41 and the second sliding groove 51. The inner sidewalls of the first sliding groove 41 and the second sliding groove 51 are provided with elongated through holes 11, which communicate with the cavity. Multiple baffles 12 are arranged transversely along the box girder body 1 to cover the first sliding groove 41 and the second sliding groove 51. The multiple baffles 12 pass through the elongated through holes 11 and can slide along the width direction of the first sliding groove 41 and the second sliding groove 51 to form a covered state covering the first sliding groove 41 and the second sliding groove 51 and an open state opening the first sliding groove 41 and the second sliding groove 51. At least one baffle 12 is arranged to avoid the first sliding connector 42 or the second sliding connector 52. Figure 6 The shield 12 located on the right is relatively large. In actual use, shields 12 of different sizes or areas can be selected according to the specific scenario to cover the slot.

[0068] A cavity is located inside the bridge deck of the box girder body 1 and beside the first chute 41. The cavity extends along the length of the first chute 41, and its width is greater than the width of the first chute 41. Its depth is sufficient to accommodate multiple side-by-side baffles 12. An elongated through hole 11 extends along the length of the first chute 41. Its length matches the length of the first chute 41, and its width matches the thickness of the baffle 12, allowing the baffle 12 to pass through and slide freely.

[0069] Multiple baffles 12 are arranged in the cavity along the transverse direction of the box girder body 1 (i.e., the width direction of the first slide groove 41). Each baffle 12 is a rectangular thin plate, the length direction of which is consistent with the width direction of the first slide groove 41, and the width direction of which is consistent with the length direction of the first slide groove 41. Each baffle 12 can slide independently along the width direction of the first slide groove 41. When a baffle 12 slides along the width direction toward the first slide groove 41 and passes the elongated through hole 11, the baffle 12 covers the opening of the first slide groove 41, forming a shield for the corresponding section of the first slide groove 41; when the baffle 12 slides back into the cavity along the width direction away from the first slide groove 41, the baffle 12 opens the corresponding section of the first slide groove 41.

[0070] When the first sliding connector 42 or the second sliding connector 52 needs to slide, the corresponding baffle 12 (i.e., the baffle 12 that hinders sliding) can be retracted into the cavity first, and then the sliding can proceed. After sliding, the baffle 12 that does not cover the first groove 41 or the second groove 51 will slide out of the cavity again, thus achieving the blocking of the groove opening. The first sliding connector 42 or the second sliding connector 52 is not interfered with by the baffle 12 during the sliding process, and at the same time, the baffle 12 can effectively cover the remaining areas of the first groove 41 and the second groove 51.

[0071] For example, through the cooperation of multiple baffles 12, this embodiment can achieve segmented coverage of the first slide groove 41: in the section corresponding to the current position of the first sliding connector 42, the baffle 12 corresponding to that section is in an open state to ensure the normal sliding of the first sliding connector 42; while in other sections not currently occupied by the first sliding connector 42, the corresponding baffle 12 is in a covered state to prevent impurities from entering the first slide groove 41.

[0072] Adjacent baffles 12 do not contact each other, but are provided with sliding fit structures, such as slide rails and slide grooves, to keep each baffle 12 stable during sliding and prevent tilting or jamming. Each baffle 12 has a sealing strip at one end near the first slide groove 41 or the second slide groove 51. When the baffle 12 is in the covered state, the sealing strip abuts against the edge of the groove of the first slide groove 41 or the second slide groove 51 to form a seal, further improving the dustproof effect.

[0073] To achieve automatic pushing of the baffle 12 and automatic switching between two states, in some embodiments, please refer to... Figures 5 to 6A pusher 13 is installed inside the cavity to push the baffle plate 12 to slide. Specifically, the pusher 13 is fixedly installed inside the cavity, and its pushing direction is set along the width direction of the first slide groove 41. The power output end of the pusher 13 is connected to the corresponding baffle plate 12 to drive the baffle plate 12 to slide back and forth along the width direction of the first slide groove 41. The pusher 13 can be any one of an electric push rod, a micro cylinder, an electromagnet, or a micro stepper motor with a lead screw and nut mechanism. In this embodiment, the pusher 13 is preferably an electric push rod, thereby driving the baffle plate 12 to switch between a covered state and an open state.

[0074] The wiring harness of the pusher 13 passes through the main body 1 of the box girder and is led out and electrically connected to the control panel. By operating the control panel, the pushing control of each pusher 13 can be realized, thereby satisfying the sliding control of multiple baffles 12, that is, the automatic blocking and opening of the slot is realized. When open, it is conducive to the sliding of the first sliding connector 42.

[0075] This invention also provides a method for adjusting a streamlined box girder wind tunnel test model, comprising the following steps: S1: Determine the lateral position parameters of the bridge deck railing assembly 2, the tilt angle of the bridge deck railing assembly 2, and the lateral position parameters of the track main body assembly 3 according to the wind tunnel test plan; S2: Use the first adjustment mechanism 4 to adjust the position of the bridge deck railing assembly 2, move it to the target position and adjust it to the target angle, and then lock it; S3: Use the second adjustment mechanism 5 to adjust the position of the track body assembly 3 and move it to the target position, then lock it; S4: Place the adjusted streamlined box girder wind tunnel test model in the wind tunnel for aerodynamic performance testing; S5: Repeat steps S1 to S4 to conduct a series of wind tunnel tests under different parameter combinations of the positions of the bridge deck railing component 2, the angle of the bridge deck railing component 2, and the positions of the main track component 3, and obtain aerodynamic performance data under different parameter combinations.

[0076] The adjustment method for a streamlined box girder wind tunnel test model provided by this invention has the same beneficial effects as the aforementioned streamlined box girder wind tunnel test model, and will not be repeated here.

[0077] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A streamlined box girder wind tunnel test model, characterized in that, include: The main body of the box girder is a streamlined closed box girder cross-section structure, with its top surface being the bridge deck and its bottom surface being the girder bottom. A bridge deck railing assembly is installed on the bridge deck of the main body of the box girder, including railing posts and railing beams. The railing posts are connected to the main body of the box girder through a first adjustment mechanism. The bridge deck railing assembly adjusts its lateral position and tilt angle with the help of the first adjustment mechanism. The track main body assembly is disposed at the bottom of the box girder main body. The track main body assembly is connected to the box girder main body through a second adjustment mechanism, and the track main body assembly adjusts its lateral position by means of the second adjustment mechanism.

2. The streamlined box girder wind tunnel test model as described in claim 1, characterized in that, The first adjustment mechanism includes: The first chute is provided on the main bridge deck of the box girder and extends laterally along the bridge deck; The first sliding connector is slidably connected within the first groove; An angle-adjusting pivot is connected at one end to the first sliding connector and at the other end to the lower end of the railing post. The railing post can rotate relative to the first sliding connector around the angle-adjusting pivot and be positioned at any angle by a locking member to adjust the tilt angle of the bridge deck railing assembly. The bridge deck railing assembly can adjust its lateral position by means of the sliding energy of the first sliding connector. A first position indicator scale is set next to the first slide groove to indicate the position of the first sliding connector; An angle indicator scale is set at the angle adjustment pivot to indicate the tilt angle of the railing post.

3. The streamlined box girder wind tunnel test model as described in claim 2, characterized in that, The first adjustment mechanism further includes: The railing drive unit is located inside the box girder body and its power output end passes through the box girder body and is connected to the first sliding connector. The railing drive unit is used to drive the first sliding connector to slide in the first groove.

4. The streamlined box girder wind tunnel test model as described in claim 1, characterized in that, The second adjustment mechanism includes: The second chute is provided on the bottom of the main beam of the box girder and extends laterally along the bottom of the beam. The second sliding connector is slidably connected within the second slide groove and can be positioned at any position to adjust the lateral position of the track main body assembly; The second position indicator scale is located next to the second slide groove and is used to indicate the position of the second sliding connector.

5. The streamlined box girder wind tunnel test model as described in claim 4, characterized in that, The second adjustment mechanism also includes: The track drive unit is located inside the box girder body and its power output end passes through the box girder body and is connected to the second sliding connector. The track drive unit is used to drive the second sliding connector to slide in the second groove.

6. The streamlined box girder wind tunnel test model as described in claim 1, characterized in that, The railing posts are equipped with height adjustment structures, and the railing beams are slidably connected to the railing posts through the height adjustment structures to adjust the height of the railing beams relative to the bridge deck.

7. The streamlined box girder wind tunnel test model as described in claim 1, characterized in that, The first adjustment mechanism and the second adjustment mechanism are each electrically connected to a control unit, which is used to control the operation of the first adjustment mechanism and the second adjustment mechanism.

8. The streamlined box girder wind tunnel test model as described in claim 2, characterized in that, A cavity is formed inside the box girder body adjacent to the first sliding groove. An elongated through hole is provided on the inner sidewall of the first sliding groove, and the elongated through hole communicates with the cavity. Multiple baffles are arranged in the cavity along the transverse direction of the box girder body and are used to cover the first sliding groove. The multiple baffles pass through the elongated through hole and can slide along the width direction of the first sliding groove to form a covered state covering the first sliding groove and an open state opening the first sliding groove. At least one of the baffles is arranged to avoid the first sliding connector.

9. A streamlined box girder wind tunnel test model as described in claim 8, characterized in that, The cavity is equipped with a pusher for pushing the baffle plate to slide.

10. The adjustment method for a streamlined box girder wind tunnel test model as described in claim 1, characterized in that, Includes the following steps: S1: Determine the lateral position parameters of the bridge deck railing assembly, the tilt angle of the bridge deck railing assembly, and the lateral position parameters of the main track assembly according to the wind tunnel test plan; S2: Use the first adjustment mechanism to adjust the position of the bridge deck railing assembly, move it to the target position and adjust it to the target angle, and then lock it; S3: Use the second adjustment mechanism to adjust the position of the main track assembly and move it to the target position, then lock it; S4: Place the adjusted streamlined box girder wind tunnel test model in the wind tunnel for aerodynamic performance testing; S5: Repeat steps S1 to S4 to conduct a series of wind tunnel tests under different parameter combinations of bridge deck railing component positions, bridge deck railing component angles, and track main component positions to obtain aerodynamic performance data under different parameter combinations.

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