Main beam mass balance weight structure suitable for full-bridge aeroelastic model and design method of main beam mass balance weight structure

Abstract

The invention relates to the technical field of bridge wind tunnel tests, and discloses a main beam mass balance weight structure suitable for a full-bridge aeroelastic model and a design method of the main beam mass balance weight structure. According to the invention, the connecting pieces forming the counterweight assembly and the plurality of counterweight pieces are arranged to be detachable parts, so that the disassembly and assembly of the counterweight assembly are facilitated as required during the full-bridge aeroelastic model wind tunnel test, and the damage to the full-bridge aeroelastic model in the disassembly and assembly process of the counterweight assembly can be effectively avoided. Meanwhile, according to the counter weight assembly with the design, the number of the counter weight parts can be increased or decreased according to the actual counter weight requirement, so that the precision of mass counter weight is guaranteed as much as possible, and recycling of the counter weight parts can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of bridge wind tunnel tests, and in particular to a main beam mass counterweight structure suitable for a full-bridge aeroelastic model and a design method thereof. Background Art

[0002] The contents in this section merely provide background information related to the present invention and may not constitute prior art.

[0003] As the span of bridges increases, the wind resistance of long-span bridges has gradually become a more significant and important issue. For long-span bridges, it is usually necessary to test the wind resistance of the bridge at various states from construction to completion. At present, the common test method is to conduct a full-bridge aeroelastic model (also known as a "full-bridge aeroelastic model") wind tunnel test.

[0004] In the known full-bridge aeroelastic model wind tunnel tests, the full-bridge aeroelastic model generally adopts a method of simulating the structural shape and stiffness separately. Among them, the structural stiffness is generally simulated by the core beam, and the structural shape is simulated by the box beam outer mold rigidly connected to the core beam. In addition, the box beam outer mold is divided into several outer mold segments along the bridge direction, and a slit is formed between two adjacent outer mold segments. The remaining structural mass characteristics of the full-bridge aeroelastic model are simulated by the core beam, the box beam outer mold and the additional mass counterweight.

[0005] For the additional mass counterweight, the known method is usually to make metal parts such as lead into strips as counterweights, and to bond the counterweights to the outer mold box of each outer mold segment using a two-liquid mixed hardening glue. However, in actual applications, the wind tunnel test of the full-bridge aeroelastic model often requires a test in the completed state before a test in the construction state, and because the quality of the full-bridge aeroelastic model in the completed state and the construction state is quite different, the mass counterweight needs to be disassembled and reinstalled after the test in the completed state. On this basis, if the counterweight is bonded to the outer mold box of each outer mold segment by bonding, there is a high probability of causing damage to the full-bridge aeroelastic model when disassembling and assembling the counterweight, especially the lightweight outer mold of the highway bridge, which may affect the progress of the test and increase the test cost. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide a main beam mass counterweight structure suitable for a full-bridge aeroelastic model, so as to simplify the disassembly and assembly process of the counterweight and reduce the risk of damage to the model when disassembling and assembling the counterweight. At the same time, the present invention also provides a design method for the main beam mass counterweight structure suitable for a full-bridge aeroelastic model.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] On the one hand, the present invention discloses a main beam mass counterweight structure suitable for a full-bridge aeroelastic model, wherein the full-bridge aeroelastic model comprises a box beam outer mold and a core beam, wherein the box beam outer mold comprises a plurality of outer mold segments spaced apart in the direction of the bridge, each of the outer mold segments comprises two outer mold boxes parallel to each other and symmetrically arranged in the left and right directions; each of the outer mold boxes is provided with two fixing members spaced apart in the direction of the bridge;

[0009] The core beam comprises two main core beams arranged along the bridge direction and a secondary core beam arranged in the transverse bridge direction, wherein one of the main core beams sequentially penetrates the outer mold box on the left side of each outer mold segment, and the other main core beam sequentially penetrates the outer mold box on the right side of each outer mold segment; the secondary core beams correspond to the outer mold segments one by one, and the two main core beams in the outer mold box of each outer mold segment are connected through the secondary core beam;

[0010] The main beam mass counterweight structure includes a counterweight assembly disposed in each of the outer mold boxes; the counterweight assembly includes a connecting piece, a plurality of counterweight pieces and a locking piece;

[0011] Both ends of the connecting member are detachably connected to the two fixing members, and the plurality of counterweight members are detachably connected to the connecting member. The locking member is used to lock or unlock the positions of the connecting member and the plurality of counterweight members connected to the connecting member.

[0012] Furthermore, the position of the connecting member in the transverse bridge direction is adjustable.

[0013] Furthermore, both of the fixing members are provided with movable grooves extending in the transverse direction of the bridge;

[0014] Both ends of the connecting member pass through the movable grooves on the two fixing members respectively, and the position of the connecting member passing through the movable groove is locked by the locking member.

[0015] Furthermore, the plurality of counterweights are equally divided into two groups, the two groups of counterweights correspond to the two fixing members respectively, and the counterweights in each group of counterweights are located on both sides of the corresponding fixing members.

[0016] Furthermore, the connecting member is a screw rod, and a plurality of the counterweights are sleeved on the outer wall of the screw rod;

[0017] The locking member includes a double-stacked washer and a locking nut. The screw rods at opposite ends of each group of the counterweights are sleeved with double-stacked washers, and the locking nut is threadedly connected to the screw rod outside each double-stacked washer.

[0018] Furthermore, the main core beam located in each of the outer mold boxes includes a plurality of longitudinal sections arranged in the longitudinal direction and a plurality of transverse sections arranged in the transverse direction.

[0019] Further, the plurality of longitudinal bridge sections include a first longitudinal bridge section, a second longitudinal bridge section, and a third longitudinal bridge section, and the plurality of transverse bridge sections include a first transverse bridge section, a second transverse bridge section, a third transverse bridge section, and a fourth transverse bridge section;

[0020] One end of the first longitudinal bridge section facing away from the previous outer mold segment is connected to one end of the second transverse bridge section, the other end of the second transverse bridge section is connected to one end of the second longitudinal bridge section, the other end of the second longitudinal bridge section is connected to one end of the third transverse bridge section, and the other end of the third transverse bridge section is connected to one end of the third longitudinal bridge section facing away from the next outer mold segment;

[0021] One end of the first transverse bridge section is connected to the first longitudinal bridge section, and the other end of the first transverse bridge section extends in a direction away from the torsional center of the main beam of the full-bridge aeroelastic model. One end of the fourth transverse bridge section is connected to the third longitudinal bridge section, and the other end of the fourth transverse bridge section extends in a direction away from the torsional center of the main beam of the full-bridge aeroelastic model.

[0022] On the other hand, the present invention discloses a design method for a main beam mass counterweight structure suitable for a full-bridge aeroelastic model, comprising the following steps:

[0023] Step S1. Determine the mass and mass moment of inertia of the scaled full-bridge aeroelastic model per unit length;

[0024] Step S2. Determine the mass per unit length of the core beam and a single outer mold segment in the scaled full-bridge aeroelastic model, and at the same time, determine the mass moment of inertia contribution of the core beam and a single outer mold segment in the scaled full-bridge aeroelastic model;

[0025] Step S3: Determine the counterweight mass and counterweight mass moment of inertia required for a single outer mold segment, and determine the position of a single counterweight assembly and the number of counterweight assemblies in a single outer mold segment.

[0026] Further, in step S2, the mass moment of inertia contribution of the core beam is expressed as:

[0027]

[0028] In the above formula, I b is the mass moment of inertia contribution of the core beam, N is the number of longitudinal members per meter of the core beam, M is the number of transverse members per meter of the core beam, r i is the horizontal distance from the mass center of each member to the torsion center of the cross-section of the aeroelastic model of the full bridge after scaling, l i is the length of the cross member, m i is the mass of a single member of the core beam per linear meter;

[0029] The mass moment of inertia contribution of a single outer mold segment is expressed as:

[0030]

[0031] In the above formula, I s is the mass inertia contribution of a single outer mold segment, b is the distance between the springs located outside the two outer mold boxes of a single outer mold segment in the elastic suspension test, λ is the ratio of the vertical frequency to the torsional frequency measured by the elastic suspension test, m s is the mass of a single outer mold segment per unit length.

[0032] Further, in step S3, the counterweight mass and counterweight mass moment of inertia required for a single outer mold segment are expressed as:

[0033] m t =(mm b -m s )t;

[0034] I t =(II b -I s )t;

[0035] In the above formula, m t is the mass of counterweight required for a single outer mold segment, I t is the mass moment of inertia of the counterweight required for a single outer mold segment, t is the length of a single outer mold segment, m is the mass per unit length of the scaled full-bridge aeroelastic model, m b is the mass of the core beam per unit length, and I is the mass moment of inertia of the scaled full-bridge aeroelastic model per unit length.

[0036] The technical solution of the embodiment of the present invention has at least the following advantages and beneficial effects:

[0037] 1. The present invention sets the connector and multiple counterweights constituting the counterweight assembly as detachable parts, which is conducive to disassembling the counterweight assembly as needed during the wind tunnel test of the full-bridge aeroelastic model, and can effectively avoid damage to the full-bridge aeroelastic model during the disassembly of the counterweight assembly. At the same time, the counterweight assembly of this design can also increase or decrease the number of counterweights according to the actual counterweight demand, so as to ensure the accuracy of the mass counterweight as much as possible, and can realize the recycling of the counterweights.

[0038] 2. The present invention makes it possible to adjust the distance from the counterweight assembly to the torsional center of the main beam of the full-bridge aeroelastic model by setting the position of the connecting piece of the counterweight assembly in the transverse direction of the bridge to be adjustable, so as to meet the differences in the mass moment of inertia of the counterweight under various working conditions.

[0039] 3. The present invention uses double-stack washers and locking nuts to lock the positions of the connector and its counterweight, which can effectively prevent the counterweight assembly from loosening under the influence of wind-induced vibration in the full-bridge aeroelastic model wind tunnel test, thereby improving the stability and reliability of the counterweight assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of the structure of a single outer mold segment in the full-bridge aeroelastic model provided in Example 1 of the present invention;

[0041] Figure 2 for Figure 1 An enlarged view of the structure at A in the middle shows the structure in a single outer mold box;

[0042] Figure 3 A schematic structural diagram of a single counterweight assembly and two fixing members thereof provided in Example 1 of the present invention;

[0043] Figure 4 It is a structural schematic diagram of a single outer mold segment undergoing an elastic suspension test in Example 2 of the present invention.

[0044] Icons: 10-outer mold segment, 11-outer mold box, 12-transverse connecting beam, 13-fixing part, 14-movable groove, 20-main core beam, 21-first longitudinal bridge section, 22-second longitudinal bridge section, 23-third longitudinal bridge section, 24-first transverse bridge section, 25-second transverse bridge section, 26-third transverse bridge section, 27-fourth transverse bridge section, 30-auxiliary core beam, 40-counterweight assembly, 41-connecting part, 42-counterweight part, 43-locking part, 431-double-stacked washer, 432-locking nut, 50-spring, 60-laser target, 70-laser displacement meter. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described in conjunction with specific implementation methods below. The same figure marks in the accompanying drawings represent the same components. It should be noted that the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described 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.

[0046] Compared to the embodiments shown in the drawings, feasible embodiments within the scope of the present invention may have fewer components, other components not shown in the drawings, different components, differently arranged components, or differently connected components, etc. In addition, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as multiple separate components.

[0047] Example 1

[0048] Embodiment 1 of the present invention discloses a main beam mass counterweight structure suitable for a full-bridge aeroelastic model, wherein the full-bridge aeroelastic model described in the embodiment of the present invention can be a double-box-beam full-bridge aeroelastic model.

[0049] In this embodiment, the full bridge aeroelastic model may include a box beam outer mold and a core beam. The box beam outer mold may include a plurality of outer mold segments 10 spaced apart in the direction of the bridge, so as to form a slit between two adjacent outer mold segments 10. Figure 1 As shown, when the full-bridge aeroelastic model is a double-box-beam full-bridge aeroelastic model, each outer mold segment 10 may further include two outer mold boxes 11 that are parallel to each other, and the two outer mold boxes 11 are basically arranged in a left-right symmetric manner with the torsion center of the main beam of the full-bridge aeroelastic model as the center. Furthermore, each outer mold segment 10 may also include a transverse connecting beam 12, and the two outer mold boxes 11 are connected by the transverse connecting beam 12.

[0050] The core beam may include two main core beams 20 arranged along the bridge direction and a secondary core beam 30 arranged transversely to the bridge direction. Figure 1 As shown, one of the main core beams 20 sequentially penetrates the outer mold box 11 on the left side of each outer mold segment 10, and the other main core beam 20 sequentially penetrates the outer mold box 11 on the right side of each outer mold segment 10. Further, the two main core beams 20 have a basically identical structure, and the two main core beams 20 can be symmetrically distributed with the torsion center of the main beam of the full-bridge aeroelastic model as the center.

[0051] The secondary core beams 30 correspond to each outer mold segment 10 one by one, and the main core beams 20 in the two outer mold boxes 11 of each outer mold segment 10 are connected through the secondary core beams 30. Figure 1 In the embodiment, one end of the auxiliary core beam 30 is connected to the main core beam 20 in the outer mold box 11 on the left side of each outer mold segment 10, and the other end of the auxiliary core beam 30 is connected to the main core beam 20 in the outer mold box 11 on the right side of each outer mold segment 10. The auxiliary core beam 30 corresponding to each outer mold segment 10 can pass through the transverse connecting beam 12 of each outer mold segment 10, and the auxiliary core beam 30 can be fixedly connected to the transverse connecting beam 12. The auxiliary core beam 30 and the two main core beams 20 can be an integrated structure.

[0052] The main core beam 20 located in each outer mold box 11 of each outer mold segment 10 may include a plurality of longitudinal segments arranged in the longitudinal direction and a plurality of transverse segments arranged in the transverse direction.

[0053] Further, in a specific embodiment of the present invention, Figure 2 As shown, the plurality of longitudinal bridge sections may include a first longitudinal bridge section 21, a second longitudinal bridge section 22, and a third longitudinal bridge section 23, and the plurality of transverse bridge sections may include a first transverse bridge section 24, a second transverse bridge section 25, a third transverse bridge section 26, and a fourth transverse bridge section 27.

[0054] Among them, the end of the first longitudinal bridge section 21 facing away from the previous outer mold segment 10 is connected to one end of the second transverse bridge section 25, the other end of the second transverse bridge section 25 is connected to one end of the second longitudinal bridge section 22, the other end of the second longitudinal bridge section 22 is connected to one end of the third transverse bridge section 26, and the other end of the third transverse bridge section 26 is connected to the end of the third longitudinal bridge section 23 facing away from the next outer mold segment 10. At this time, the second transverse bridge section 25, the second longitudinal bridge section 22 and the third transverse bridge section 26 together form a right-angle groove protruding toward the torsion center of the main beam of the full-bridge aeroelastic model. And the aforementioned connection between the auxiliary core beam 30 and the main core beam 20 can be the connection between the auxiliary core beam 30 and the second longitudinal bridge section 22, and the connection position of the two can be located at the center of the second longitudinal bridge section 22.

[0055] One end of the first transverse bridge section 24 is connected to the first longitudinal bridge section 21, and the other end of the first transverse bridge section 24 extends in a direction away from the torsion center of the main beam of the full-bridge aeroelastic model. One end of the fourth transverse bridge section 27 is connected to the third longitudinal bridge section 23, and the other end of the fourth transverse bridge section 27 extends in a direction away from the torsion center of the main beam of the full-bridge aeroelastic model. This is conducive to improving the structural strength of the outer mold box 11.

[0056] Further, continue to refer to Figure 2 , two fixing members 13 spaced apart in the longitudinal direction can be set in each outer mold box 11 of each outer mold segment 10, and each fixing member 13 is arranged along the transverse direction. Among them, the second longitudinal section 22 of the main core beam 20 in each outer mold box 11 passes through two fixing members 13 at the same time. Among them, the fixing member 13 can be a plate-shaped stiffening plate. The function of the two fixing members 13 is to further improve the structural strength of the outer mold box 11 and provide a mounting carrier for the counterweight assembly 40 to be described below.

[0057] In this embodiment, combined with Figure 1 or Figure 2As shown in the figure, the main beam mass counterweight structure may include a counterweight assembly 40 disposed in each outer mold box 11. In other words, each outer mold box 11 is provided with a counterweight assembly 40. For example, this embodiment shows a situation where each outer mold box 11 is provided with a counterweight assembly 40. Of course, in other embodiments of the present invention, the number of counterweight assemblies 40 in each outer mold box 11 is not limited thereto.

[0058] Further, see Figure 3 As shown, each counterweight assembly 40 includes a connecting member 41, a plurality of counterweight members 42, and a locking member 43. The two ends of the connecting member 41 are detachably connected to the two fixing members 13. The plurality of counterweight members 42 are detachably connected to the connecting member 41, and the locking member 43 is used to lock or unlock the position of the connecting member 41 and the plurality of counterweight members 42 connected to the connecting member 41.

[0059] It can be understood that the counterweight assembly 40 constructed by adopting the method is based on the fact that the connecting member 41 and the plurality of counterweight members 42 are all detachable parts, so it is conducive to disassembling and assembling the counterweight assembly 40 in each outer mold box 11 as needed during the full-bridge aeroelastic model wind tunnel test, and can effectively avoid damage to the full-bridge aeroelastic model during the disassembly and assembly of the counterweight assembly 40. At the same time, the counterweight assembly 40 of this design can also increase or decrease the number of counterweight members 42 according to the actual counterweight demand, so as to ensure the accuracy of the mass counterweight as much as possible, and can realize the recycling and reuse of the counterweight members 42.

[0060] For example, counterweights 42 of different masses can be prepared in advance so as to configure a counterweight assembly 40 with a mass that meets the requirements as needed. For example, counterweights 42 of masses of 50g, 20g, 10g, 5g and 1g can be prepared in advance for use.

[0061] Secondly, considering that the counterweight mass moment of inertia required under different working conditions is different, in order to be able to meet the counterweight mass moment of inertia under various working conditions, the embodiment of the present invention further limits the position of the connecting member 41 in the transverse bridge direction to be adjustable. In this way, for different working conditions, it is only necessary to adjust the position of the connecting member 41 in the transverse bridge direction to change the distance from the entire counterweight assembly 40 to the torsional center of the main beam of the full-bridge aeroelastic model, so as to meet the counterweight mass moment of inertia under various working conditions.

[0062] The position of the connecting member 41 in the transverse direction can be adjusted in the following manner but is not limited thereto.

[0063] like Figure 3As shown, both fixing members 13 are provided with movable grooves 14 extending in the transverse bridge direction. At this time, the two ends of the connecting member 41 pass through the movable grooves 14 on the two fixing members 13 respectively, and the position of the connecting member 41 passing through the movable grooves 14 is locked by the locking member 43. In this way, when it is necessary to adjust the position of the connecting member 41 in the transverse bridge direction, first operate the locking member 43 to unlock the position of the connecting member 41, and then change the position of the connecting member 41 in the transverse bridge direction by moving the connecting member 41 in the movable grooves 14 on the two fixing members 13. After the connecting member 41 moves to the predetermined position, the locking member 43 can be used to lock the position of the connecting member 41. The operation is simple and convenient. Moreover, by adopting this method, the position of the connecting member 41 can be adjusted without removing the counterweight 42 on the connecting member 41.

[0064] In order to further optimize the structural design of the counterweight assembly 40 and make the counterweight more uniform, continue to refer to Figure 3 The plurality of counterweights 42 detachably connected to the connecting member 41 can be equally divided into two groups. The two groups of counterweights 42 correspond to the two fixing members 13 respectively, and the counterweights 42 in each group of counterweights 42 can be located on both sides of the corresponding fixing member 13.

[0065] For example, in Figure 3 In the illustrated counterweight assembly 40, a single counterweight assembly 40 includes eight counterweights 42. At this time, the eight counterweights 42 are equally divided into two groups, and each group of counterweights 42 has four counterweights 42. In addition, the four counterweights 42 in each group of counterweights 42 are located on both sides of the corresponding fixing member 13. Further, one of the four counterweights 42 can be arranged on the outside of the corresponding fixing member 13 (that is, the side of the fixing member 13 facing away from the other fixing member 13), and the remaining three of the four counterweights 42 can be arranged in sequence on the inside of the corresponding fixing member 13 (that is, the side of the fixing member 13 facing the other fixing member 13).

[0066] Secondly, considering that the wind-induced vibration in the full-bridge aeroelastic model wind tunnel test may cause the counterweight assembly 40 to loosen, thereby causing adverse effects on the test. To this end, the present invention further improves the structure of the connecting member 41 and the locking member 43, in the hope of preventing the counterweight assembly 40 from loosening during the test.

[0067] Specifically, combined Figure 3 As shown, the connecting member 41 can further be a screw rod with an external thread on the outer wall. At this time, the plurality of counterweights 42 can be components sleeved on the outer wall of the screw rod. For example, the counterweight 42 can be a component with a hole for the screw rod to pass through.

[0068] The locking member 43 may include a double-stacked washer 431 and a locking nut 432. The double-stacked washer 431 is mounted on the screw rods at opposite ends of each group of counterweights 42, and the locking nut 432 is threadedly connected to the screw rod on the outside of each double-stacked washer 431 (i.e., the side away from the corresponding counterweight 42).

[0069] It is understandable that the double-stack washer 431 is also called a loose-proof washer. The double-stack washer 431 generally includes two opposed washers, and the two washers are each provided with a larger first tooth portion on one side opposite to the other, and the two washers are each provided with a smaller second tooth portion on the other side. Among them, the side of the washer provided with the first tooth portion can be called the large tooth surface of the washer, and the first tooth portion on the large tooth surface can be processed into a large tooth bevel, and the side of the washer provided with the second tooth portion can be called the small tooth surface of the washer, and the second tooth portion on the small tooth surface can be processed into radial straight teeth or arc teeth. In actual application, the large tooth surfaces of the two washers of a single double-stack washer 431 can be wedge-engaged to achieve the self-locking function of the double-stack washer 431, and the small tooth surface of the washer close to the locking nut 432 can be wedged into the corresponding locking nut 432, so that after the locking nut 432 is pre-tightened, the position of the screw rod and the counterweight 42 on the screw rod can be reliably locked, thereby effectively preventing the counterweight assembly 40 from loosening under the influence of wind-induced vibration.

[0070] Example 2

[0071] Embodiment 2 of the present invention discloses a design method for a main beam mass counterweight structure suitable for a full-bridge aeroelastic model. The full-bridge aeroelastic model and the main beam mass counterweight structure described in this embodiment may be the full-bridge aeroelastic model and the main beam mass counterweight structure described in the above-mentioned embodiment 1.

[0072] Through this design method, at least the counterweight mass and counterweight mass moment of inertia required for a single outer mold segment 10 in the full-bridge aeroelastic model can be calculated, and the distance from the counterweight assembly 40 corresponding to each outer mold box 11 to the torsional center of the main beam of the full-bridge aeroelastic model and the number of counterweight assemblies 40 required for a single outer mold segment 10 can be obtained.

[0073] Specifically, the design method may include the following steps:

[0074] Step S1. Determine the mass and mass moment of inertia of the scaled full-bridge aeroelastic model per unit length. It is worth noting that the unit length in this embodiment may be per linear meter.

[0075] Wherein, in step S1, the mass and mass moment of inertia of the scaled full-bridge aeroelastic model per unit length can be determined based on the main beam mass, main beam mass moment of inertia and geometric scale ratio of the full-bridge aeroelastic model.

[0076] First, the geometric scale ratio of the full-bridge aeroelastic model is determined according to the span of the actual bridge and the size of the wind tunnel test section. The geometric scale ratio of the full-bridge aeroelastic model is expressed as:

[0077] C L =1 / n=l / L;

[0078] In the above formula, C L is the geometric scale ratio of the full-bridge aeroelastic model, n is the inverse of the geometric scale ratio, L is the main beam span of the actual bridge, and l is the main beam span of the full-bridge aeroelastic model.

[0079] On this basis, the geometric scale ratio of the mass of the scaled full-bridge aeroelastic model and the geometric scale ratio of the mass moment of inertia are determined. The geometric scale ratio of the mass of the scaled full-bridge aeroelastic model and the geometric scale ratio of the mass moment of inertia are expressed as follows:

[0080] C M =1 / n 2 ;

[0081] C I =1 / n 4 ;

[0082] In the above two formulas, C M is the geometric scale ratio of the mass of the scaled full-bridge aeroelastic model, C I is the geometric scale ratio of the mass of the scaled full-bridge aeroelastic model.

[0083] Then, the mass and mass moment of inertia of the scaled full-bridge aeroelastic model per unit length are expressed as:

[0084] m=M P ·C M ;

[0085] I=I P ·C I ;

[0086] In the above two equations, m is the mass per unit length of the scaled full-bridge aeroelastic model, I is the mass moment of inertia per unit length of the scaled full-bridge aeroelastic model, and M is P is the actual mass of the bridge per linear meter, I P is the mass moment of inertia per linear meter of the actual bridge.

[0087] Step S2. Based on step S1, determine the mass per unit length of the core beam and a single outer mold segment 10 in the scaled full-bridge aeroelastic model, and at the same time, determine the mass moment of inertia contribution of the core beam and a single outer mold segment 10 in the scaled full-bridge aeroelastic model.

[0088] It should be noted that the mass moment of inertia contribution described in this embodiment can be understood as the proportion of mass moment of inertia. For example, the mass moment of inertia contribution of the core beam can be understood as the proportion of the mass moment of inertia of the core beam in the mass moment of inertia of the entire scaled full-bridge aeroelastic model. Correspondingly, the mass moment of inertia contribution of a single outer mold segment 10 can be understood as the proportion of the mass moment of inertia of a single outer mold segment 10 in the mass moment of inertia of the entire scaled full-bridge aeroelastic model.

[0089] In step S2, the mass of the core beam per unit length can be directly calculated according to the size of the core beam and the material density, and is recorded as m b The mass per unit length of a single outer mold segment 10 can be directly weighed after the processing of the single outer mold segment 10 is completed, and is recorded as m s .

[0090] In step S2, the mass moment of inertia contribution of the core beam and the single outer mold segment 10 of the scaled full-bridge aeroelastic model can be based on the mass m of the core beam per unit length. b and the mass m of a single outer mold segment 10 per unit length s to be sure.

[0091] Among them, the mass moment of inertia contribution of the core beam is expressed as:

[0092]

[0093] In the above formula, I b is the mass inertia contribution of the core beam, N is the number of members along the bridge per meter of the core beam, M is the number of members across the bridge per meter of the core beam, r i is the horizontal distance from the mass center of each member to the torsion center of the aeroelastic model of the full bridge after scaling, l i is the length of the cross member, m i is the mass of a single member of the core beam per linear meter, and:

[0094] It should be noted that the aforementioned longitudinal bridge members and transverse bridge members refer to the longitudinal extension part and transverse extension part of the main core beam 20 in each outer mold box 11, respectively. For example, as shown in Reference 2, in the main core beam 20 in each outer mold box 11 described in Example 1, the first longitudinal bridge section 21, the second longitudinal bridge section 22 and the third longitudinal bridge section 23 can be regarded as longitudinal bridge members, and the first transverse bridge section 24, the second transverse bridge section 25, the third transverse bridge section 26 and the fourth transverse bridge section 27 can be regarded as transverse bridge members.

[0095] Among them, the mass moment of inertia contribution of a single outer mold segment 10 can be obtained as follows Figure 4 The elastic suspension test shown is obtained. Figure 4In the elastic suspension test shown, springs 50 are suspended on both upper and lower sides of the outer side of each outer mold box 11 of a single outer mold segment 10, and a laser target 60 is provided near the outer edge of each outer mold box 11. The laser target 60 is used for the laser displacement meter 70 to identify and measure the vertical frequency and torsional frequency of the entire test system. It can be understood that the elastic suspension test for a single outer mold segment 10 described here is a test method known in the prior art, and will not be described in detail here.

[0096] Furthermore, the mass moment of inertia contribution of a single outer mold segment 10 can be expressed as:

[0097]

[0098] In the above formula, I s is the mass moment of inertia contribution of a single outer mold segment 10, and b is Figure 4 The spacing between the springs 50 located outside the two outer mold boxes 11 of a single outer mold segment 10 in the elastic suspension test shown, λ is the ratio of the vertical frequency to the torsional frequency measured by the elastic suspension test.

[0099] Step S3 . Based on step S1 and step S2 , determine the counterweight mass and counterweight mass moment of inertia required for a single outer mold segment 10 , and determine the position of a single counterweight assembly 40 and the number of counterweight assemblies 40 in a single outer mold segment 10 .

[0100] In step S3, the counterweight mass and counterweight mass moment of inertia required for a single outer mold segment 10 can be expressed as:

[0101] m t =(mm b -m s )t;

[0102] I t =(II b -I s )t.

[0103] In the above two formulas, m t is the mass of counterweight required for a single outer mold segment 10, I t is the mass moment of inertia of the counterweight required for a single outer mold segment 10 , and t is the length of a single outer mold segment 10 .

[0104] On this basis, the distance from a single counterweight assembly 40 to the torsion center of the main beam of the scaled full-bridge aeroelastic model can be obtained, wherein the distance from a single counterweight assembly 40 to the torsion center of the main beam of the scaled full-bridge aeroelastic model is expressed as:

[0105]

[0106] In the above formula, r ti is the distance from a single counterweight assembly 40 to the torsion center of the main beam of the scaled full-bridge aeroelastic model, m ti is the mass of a single counterweight assembly 40, I ti is the mass moment of inertia of a single counterweight assembly 40. And, m ti and I ti It can be further expressed as:

[0107]

[0108] In the above two formulas, K is the number of counterweight assemblies 40 required for a single outer mold segment 10 .

[0109] It can be seen that when actually configuring the counterweight assembly 40, it is only necessary to reasonably configure the number of counterweight assemblies 40 in a single outer mold segment 10 and the mass and mass moment of inertia of a single counterweight assembly 40 according to the actual working conditions, so that the total mass and total mass moment of inertia of the counterweight assembly 40 in a single outer mold segment 10 meet the counterweight mass m required by the single outer mold segment 10. t and the counterweight mass moment of inertia I t , the final full-bridge aeroelastic model can meet the relevant test requirements.

[0110] In combination with the contents described in Example 1, it can be seen that when a single counterweight assembly 40 includes multiple counterweights 42, counterweights 42 with different masses can be prepared in advance, so that a counterweight assembly 40 with a mass that meets the requirements can be configured later according to the above formula. For example, counterweights 42 with masses of 50g, 20g, 10g, 5g, and 1g can be prepared in advance for use.

[0111] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A main beam mass counterweight structure suitable for a full-bridge aeroelastic model, characterized in that: The full-bridge aeroelastic model comprises a box girder outer mold and a core girder, the box girder outer mold comprises a plurality of outer mold segments spaced apart in the direction of the bridge, each of the outer mold segments comprises two outer mold boxes parallel to each other and symmetrically arranged in the left and right directions; each of the outer mold boxes is provided with two fixing members spaced apart in the direction of the bridge; The core beam comprises two main core beams arranged along the bridge direction and a secondary core beam arranged in the transverse bridge direction, wherein one of the main core beams sequentially penetrates the outer mold box on the left side of each outer mold segment, and the other main core beam sequentially penetrates the outer mold box on the right side of each outer mold segment; the secondary core beams correspond to the outer mold segments one by one, and the two main core beams in the outer mold box of each outer mold segment are connected through the secondary core beam; The main beam mass counterweight structure includes a counterweight assembly disposed in each of the outer mold boxes; the counterweight assembly includes a connecting piece, a plurality of counterweight pieces and a locking piece; Both ends of the connecting member are detachably connected to the two fixing members, and the plurality of counterweight members are detachably connected to the connecting member. The locking member is used to lock or unlock the positions of the connecting member and the plurality of counterweight members connected to the connecting member.

2. The main beam mass counterweight structure suitable for the full-bridge aeroelastic model according to claim 1 is characterized in that: The position of the connecting member in the transverse bridge direction is adjustable.

3. The main beam mass counterweight structure suitable for the full-bridge aeroelastic model according to claim 2 is characterized in that: Both of the fixing members are provided with movable grooves extending in the transverse direction of the bridge; Both ends of the connecting member pass through the movable grooves on the two fixing members respectively, and the position of the connecting member passing through the movable groove is locked by the locking member.

4. The main beam mass counterweight structure suitable for the full-bridge aeroelastic model according to claim 1 is characterized in that: The plurality of counterweights are equally divided into two groups, the two groups of counterweights correspond to the two fixing members respectively, and the counterweights in each group of counterweights are located on both sides of the corresponding fixing members.

5. The main beam mass counterweight structure suitable for the full-bridge aeroelastic model according to claim 4 is characterized in that: The connecting piece is a screw rod, and the plurality of counterweight pieces are sleeved on the outer wall of the screw rod; The locking member includes a double-stacked washer and a locking nut. The screw rods at opposite ends of each group of the counterweights are sleeved with double-stacked washers, and the locking nut is threadedly connected to the screw rod outside each double-stacked washer.

6. The main beam mass counterweight structure suitable for a full-bridge aeroelastic model according to claim 1 is characterized in that: The main core beam located in each of the outer mold boxes includes a plurality of longitudinal sections arranged in the longitudinal direction and a plurality of transverse sections arranged in the transverse direction.

7. The main beam mass counterweight structure suitable for the full-bridge aeroelastic model according to claim 6 is characterized in that: The plurality of longitudinal bridge sections include a first longitudinal bridge section, a second longitudinal bridge section, and a third longitudinal bridge section; the plurality of transverse bridge sections include a first transverse bridge section, a second transverse bridge section, a third transverse bridge section, and a fourth transverse bridge section; One end of the first longitudinal bridge section facing away from the previous outer mold segment is connected to one end of the second transverse bridge section, the other end of the second transverse bridge section is connected to one end of the second longitudinal bridge section, the other end of the second longitudinal bridge section is connected to one end of the third transverse bridge section, and the other end of the third transverse bridge section is connected to one end of the third longitudinal bridge section facing away from the next outer mold segment; One end of the first transverse bridge section is connected to the first longitudinal bridge section, and the other end of the first transverse bridge section extends in a direction away from the torsional center of the main beam of the full-bridge aeroelastic model. One end of the fourth transverse bridge section is connected to the third longitudinal bridge section, and the other end of the fourth transverse bridge section extends in a direction away from the torsional center of the main beam of the full-bridge aeroelastic model.

8. A design method for the main beam mass counterweight structure suitable for a full-bridge aeroelastic model, characterized in that: The following steps are involved: Step S1. Determine the mass and mass moment of inertia of the scaled full-bridge aeroelastic model per unit length; Step S2. Determine the mass per unit length of the core beam and a single outer mold segment in the scaled full-bridge aeroelastic model, and at the same time, determine the mass moment of inertia contribution of the core beam and a single outer mold segment in the scaled full-bridge aeroelastic model; Step S3: Determine the counterweight mass and counterweight mass moment of inertia required for a single outer mold segment, and determine the position of a single counterweight assembly and the number of counterweight assemblies in a single outer mold segment.

9. The design method of the main beam mass counterweight structure applicable to the full-bridge aeroelastic model according to claim 8 is characterized in that: In step S2, the mass moment of inertia contribution of the core beam is expressed as: In the above formula, I b is the mass moment of inertia contribution of the core beam, N is the number of longitudinal members per meter of the core beam, M is the number of transverse members per meter of the core beam, r i is the horizontal distance from the mass center of each member to the torsion center of the cross-section of the aeroelastic model of the full bridge after scaling, l i is the length of the cross member, m i is the mass of a single member of the core beam per linear meter; The mass moment of inertia contribution of a single outer mold segment is expressed as: In the above formula, I s is the mass inertia contribution of a single outer mold segment, b is the distance between the springs located outside the two outer mold boxes of a single outer mold segment in the elastic suspension test, λ is the ratio of the vertical frequency to the torsional frequency measured by the elastic suspension test, m s is the mass of a single outer mold segment per unit length.

10. The design method of the main beam mass counterweight structure applicable to the full-bridge aeroelastic model according to claim 9, characterized in that: In step S3, the counterweight mass and counterweight mass moment of inertia required for a single outer mold segment are expressed as: m t =(m-m b -m s )t; I t =(I-I b -I s )t; In the above formula, m t is the mass of counterweight required for a single outer mold segment, I t is the mass moment of inertia of the counterweight required for a single outer mold segment, t is the length of a single outer mold segment, m is the mass per unit length of the scaled full-bridge aeroelastic model, m b is the mass of the core beam per unit length, and I is the mass moment of inertia of the scaled full-bridge aeroelastic model per unit length.

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