A liquid tuned mass damper and design method

Abstract

The present application relates to the technical field of building vibration reduction, and provides a liquid tuned mass damper and a design method, wherein the liquid tuned mass damper comprises a mass block, an elastic element and an oscillation plate; one end of the elastic element can be connected to a controlled structure, the mass block is connected to the other end of the elastic element; the oscillation plate is connected to the mass block; the oscillation plate and the elastic element have an included angle in the extension direction; and the oscillation plate can be immersed in a fluid. The liquid tuned mass damper can solve the problems that the existing tuned mass damper only generates inertial mass by the mass block, a mass block with a large mass is required, and a mechanical oil pressure damping element is required, resulting in high manufacturing cost, and the mass block is too heavy to cause a large static load on the controlled structure.

Description

Technical Field

[0001] This invention relates to the field of building vibration reduction technology, and in particular to a liquid tuned mass damper and its design method. Background Technology

[0002] A tuned mass damper (TMD) typically consists of a mass block, a spring, and a damping element. The mass block is connected to the controlled structure via the spring, and the damping element dissipates the vibrational energy of the mass block and the spring. The frequency of the tuned mass damper is adjusted to be close to the frequency of the controlled structure. When the controlled structure vibrates, the tuned mass damper will resonate, thereby transferring most of the vibrational energy of the controlled structure to the mass block and dissipating it through the damping element, thus achieving vibration reduction.

[0003] However, this type of tuned mass damper generates inertial mass only through the mass block. Therefore, when the vibration reduction performance requirement is high, the physical mass of the mass block is also high, which leads to increased material consumption and manufacturing costs of the mass block. In addition, the excessively large mass block will also generate a greater load on the controlled structure, which will have an adverse effect on the stress on the controlled structure. At the same time, current dampers widely use mechanical hydraulic damping elements, which have complex structures, high costs, and will show significant performance degradation after long-term use, requiring replacement, which further increases the cost of use. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of existing tuned mass dampers that generate inertial mass solely from a mass block, requiring a massive mass block and mechanical hydraulic damping elements, resulting in high manufacturing costs and the mass block placing a significant load on the controlled structure. This invention provides a liquid tuned mass damper and its design method.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A liquid-tuned mass damper includes a mass block, an elastic element, and an oscillating plate; one end of the elastic element can be connected to a controlled structure, and the mass block is connected to the other end of the elastic element; the oscillating plate is connected to the mass block; the oscillating plate has an angle with the extension and contraction direction of the elastic element; the oscillating plate can be immersed in a fluid.

[0007] Both the mass block and the spring are based on existing tuned mass dampers, as long as they can provide the functions of inertial mass and buffer energy storage respectively.

[0008] The oscillating plate can be a plate of various shapes, such as round or square plates; the oscillating plate has an angle with the direction of extension and contraction of the elastic element. If a cylindrical spring is used, the surface of the oscillating plate can be perpendicular to the axis of the cylindrical spring; the specific connection structure between the oscillating plate and the mass block depends on the structure of the controlled structure and the location of the fluid, as long as the oscillating plate can be inserted into the fluid; the fluid can be a natural lake or river, or an artificial pool; the fluid can be any liquid that can cause the oscillating plate to oscillate and generate additional mass and damping, such as water or oil; the oscillating plate should preferably be made of a material with sufficient strength and resistance to fluid corrosion.

[0009] The liquid tuned mass damper of this scheme connects an oscillating plate to the mass block, and the oscillating plate can be immersed in the fluid. When the controlled structure vibrates, the vibration energy is transferred to the mass block through the spring, so that the mass block and the controlled structure vibrate together. The oscillating plate also vibrates with the mass block. Since the oscillating plate and the elastic element have an angle between their extension and contraction directions, that is, the plate surface of the oscillating plate has an angle with its motion direction in the fluid, the interaction between the fluid and the oscillating plate will generate additional damping and additional mass on the oscillating plate. This will dissipate vibration energy and increase the inertial mass of this scheme. This scheme can eliminate the mechanical hydraulic damper in traditional tuned mass dampers and relatively reduce the physical mass of the mass block. This solves the problems of existing tuned mass dampers having large mass blocks and using mechanical hydraulic damping elements, resulting in high manufacturing costs, and the excessive weight of the mass block causing a large load on the controlled structure.

[0010] Meanwhile, this scheme uses a combination of elastic elements and oscillating plates. By adjusting the stiffness of the elastic elements and the size of the oscillating plates, the tuning frequency ratio and tuning damping ratio of this scheme can be made close to the optimal frequency ratio and optimal damping ratio, respectively. This reduces the design difficulty of this scheme and makes it easier for the vibration reduction performance of this scheme to approach the optimal value.

[0011] As a preferred embodiment of the present invention, it further includes a limiting mechanism; the limiting mechanism is used to restrict the movement of the mass block along the extension and retraction direction of the elastic element.

[0012] The limiting mechanism can take various forms, such as sliding supports or slide rails and sliders, as long as it can restrict the mass block to move only along the direction of extension and contraction of the controlled structure.

[0013] This solution adds a limiting mechanism to the mass block, ensuring that the controlled structure can only move along the direction of the elastic element's extension and contraction, i.e., the direction of vibration controlled by this solution. This prevents the mass block from moving or rotating in other directions without affecting the vibration reduction effect of this solution, thus avoiding any impact on the vibration reduction effect or the possibility of collision with other structures.

[0014] As a preferred embodiment of the present invention, the limiting mechanism includes a pulley; one end of the pulley is mounted on the controlled structure; and the other end of the pulley abuts against the mass block.

[0015] The other end of the pulley abuts against the mass block. The pulley arrangement can take various forms, such as the pulley directly abutting against the side wall of the mass block, or a dedicated track is provided for the pulley on the side wall of the mass block.

[0016] This solution uses a pulley mechanism as the limiting mechanism. The pulley is not prone to jamming during movement, ensuring reliable operation. Furthermore, the pulley mechanism does not require high processing quality for its traveling surface, reducing the processing difficulty and thus lowering processing costs. In addition, this solution fixes the pulley to the controlled structure. As long as the dimension of the mass block along the extension and contraction direction of the elastic element is greater than the stroke of the elastic element, the connection between the pulley and the mass block can be maintained throughout the entire movement of the mass block along the extension and contraction direction of the elastic element. Compared with other solutions, such as fixing the pulley to the mass block, this solution has smaller dimensional requirements for the controlled structure along the extension and contraction direction of the elastic element, making it easier to adapt to existing building structures.

[0017] As a preferred embodiment of the present invention, a protective sleeve is also included; both the mass block and the elastic element are located within the protective sleeve; the protective sleeve is used to prevent fluid from contacting the elastic element and the mass block.

[0018] The protective sleeve can be of various structural forms, such as a box with an opening in the connection structure between the oscillating plate and the mass block, as long as it can protect the mass block and elastic element from direct contact with the fluid and does not hinder the vibration of the oscillating plate.

[0019] This design includes protective sleeves for the mass block and elastic element to prevent fluid from scouring them and affecting their movement, which in turn would compromise the vibration reduction effect of the design. The protective sleeves also prevent corrosion of the mass block and elastic element under fluid scouring.

[0020] As a preferred embodiment of the present invention, the elastic element is a helical spring.

[0021] One or more helical springs can be installed depending on the actual situation.

[0022] This solution uses a helical spring as the elastic element, which has the advantages of high load-bearing capacity, reliable operation, and low cost.

[0023] As a preferred embodiment of the present invention, the oscillating plate is a PVC material component.

[0024] This solution recommends using PVC material for the oscillating plate, which is lightweight and corrosion-resistant. This reduces the load on the controlled structure and ensures the service life of the oscillating plate.

[0025] A design method for a liquid tuned mass damper, applied to a liquid tuned mass damper of the present invention, includes the following steps:

[0026] A. Determine the initial mass m of the mass block based on vibration reduction requirements. T The additional mass coefficient C of the oscillating plate m0 And obtain the total mass ratio Ω; based on the amplitude of the harmonic external load F0 and the stiffness k of the controlled structure. s The formulas for calculating the external load amplitude ratio f and Ω are as follows:

[0027]

[0028]

[0029] In the formula, Ω is the total mass ratio, μ is the physical mass ratio, β is the added mass ratio, and m T Let m be the physical mass of the mass block. s Let ρ be the mass of the controlled structure, ρ be the fluid density, L be the characteristic length of the oscillating plate, and C be the mass of the controlled structure. m0 To initially determine the additional mass coefficient;

[0030] B. The optimal frequency ratio ν of the liquid-tuned mass damper is obtained based on the analytical formulas for Ω, f, and the optimal parameters. opt and optimal damping ratio γ opt ;

[0031] C. According to γ opt Determine the dimensions of the oscillating plate; experimentally measure the actual added mass coefficient C of the oscillating plate. m ;

[0032] D. According to ν opt and C m Determine the stiffness of the elastic element.

[0033] In step A, if higher vibration reduction performance is required, a larger value for m can be used. T and C m0 This results in a higher Ω; conversely, if cost reduction is required, a smaller m can be used. T and C m0 This reduces the size of the mass block and the oscillating plate, thereby reducing costs;

[0034] In step B, the optimal frequency ratio ν opt and optimal damping ratio γ optFor specific calculations, please refer to the existing optimization theory of tuned mass dampers;

[0035] In step C, according to γ opt The dimensions of the oscillating plate are determined by adjusting them through theoretical calculations or experimental analysis, so that the overall tuning damping ratio of this scheme is as close as possible to or equal to γ. opt ;

[0036] In step D, according to v opt and C m Determine the stiffness of the elastic element, that is, adjust the stiffness of the elastic element to make the overall tuning frequency ratio of this scheme as close as possible to or equal to v. opt It should be noted that C m The actual additional mass coefficient C of the oscillating plate measured in step C. m .

[0037] The liquid tuned mass damper design method described in this scheme, applied to a liquid tuned mass damper of this invention, involves first determining the total mass ratio Ω, and then determining the optimal frequency ratio v based on the total mass ratio Ω and the external load amplitude ratio f. opt and optimal damping ratio γ opt Then through the optimal damping ratio γ opt Determine the size of the oscillator plate, and finally use v opt and C m The order of determining the stiffness of elastic elements can be obtained experimentally to obtain the most realistic possible C. m It also participates in the calculation of the elastic element stiffness, thereby making the calculated elastic element stiffness as close as possible to the optimal value, and thus making the tuning frequency ratio of the liquid tuned mass damper designed in this scheme as close as possible to v. opt And achieve the best vibration reduction performance.

[0038] As a preferred embodiment of the present invention, in step B, ν is calculated according to the following formulas. opt and γ opt :

[0039]

[0040]

[0041] The optimal frequency ratio ν of this scheme opt and optimal damping ratio γ opt The calculation formula is derived by introducing the Morison equation and combining it with the specific structure of this scheme. Specifically, after introducing the Morison equation into the liquid tuned mass damper of this scheme, the following formula can be obtained:

[0042]

[0043] In the formula, x s (t) represents the displacement of the controlled structure. The velocity of the displacement of the controlled structure. Let x be the acceleration of the displacement of the controlled structure. T (t) represents the displacement of the mass block. The velocity of the mass block's displacement. Let k be the acceleration of the mass block's displacement. s Let k be the stiffness of the controlled structure. T For the stiffness of the spring, c s The damping of the controlled structure is given by F(t), and the external load is given by c. m For the additional quality coefficient, c d For additional damping coefficient;

[0044] Assume there exists a linear damping coefficient c. T To make the equations of motion equivalent to the above equation, the approximate equivalent linearized equations are given below:

[0045]

[0046] Let the external load be F(t) = F0cos(ωt), and assume the damping coefficient of the column structure is c. s =0, introduce the dimensionless parameter ξ T =c T / 2m T ω T The expression for the dynamic amplification factor (DMF) of the controlled structure can be obtained as follows:

[0047]

[0048]

[0049] λ=ω / ω s

[0050] In the formula, λ is the external load frequency ratio, ν is the tuning frequency ratio, and ω is the external load frequency. s The natural frequency of the controlled structure;

[0051] According to Den Hartog's fixed-point theory, at different damping ratios ξ T Below, the DMF of the controlled structure s The curve always passes through two fixed points, P and Q, which indicates that DMF s In the expression, points P and Q are related to ξ T They are independent of each other, when ξ T When the value is 0 and ∞, DMF sThe values ​​of the expressions should be equal, and the optimal parameters can be obtained by minimizing the maximum value of the displacement dynamic amplification factor curve, which is the optimal frequency ratio v of this scheme. opt and optimal damping ratio γ opt Calculation formula.

[0052] As a preferred embodiment of the present invention, step C includes the following steps:

[0053] C1, according to C m0 Several oscillating plates of different sizes were fabricated; the additional damping ratio C of each oscillating plate was measured by free vibration test. d ;

[0054] C2, according to C d With γ opt The size of the oscillating plate is determined by the closest oscillating plate.

[0055] This approach recommends first fabricating several oscillating plates, and then experimentally determining the c-value of each oscillating plate. d The hydrodynamic parameters, including those included, are then selected using c. d With γ opt Using the closest approximating oscillator as the oscillator in this scheme is more convenient and faster than calculating the oscillator size theoretically, and it also yields more accurate hydrodynamic parameters of the oscillator, such as c. d and c m This allows for more accurate calculations in subsequent elastic element designs. d and c m This makes the tuning frequency of this scheme closer to ν. opt .

[0056] In a preferred embodiment of the present invention, the stiffness of the elastic element is calculated in step D according to the following formula:

[0057]

[0058] In the formula, k T ρ is the stiffness of the elastic element, ρ is the density of the fluid, L is the characteristic length of the oscillating plate, and ω is the fluid density. s is the natural frequency of the controlled structure.

[0059] This scheme provides a specific formula for calculating the stiffness of an elastic element. This formula is derived from the natural frequency formula of this scheme. Specifically, the natural frequency ω of this scheme... T The calculation formula is:

[0060]

[0061] The formula for calculating the tuning frequency ratio ν in this scheme is:

[0062]

[0063] Make ν = v opt This formula can then be obtained.

[0064] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0065] 1. The liquid tuned mass damper of this scheme connects an oscillating plate to the mass block, and the oscillating plate can be immersed in the fluid. When the controlled structure vibrates, the vibration energy is transferred to the mass block through the spring, so that the mass block and the controlled structure vibrate together. The oscillating plate will also vibrate with the mass block. Since the oscillating plate and the elastic element have an angle between their extension and contraction directions, that is, the plate surface of the oscillating plate has an angle with its motion direction in the fluid, the interaction between the fluid and the oscillating plate will generate additional damping and additional mass on the oscillating plate. This will dissipate vibration energy and increase the inertial mass of this scheme. This scheme can eliminate the mechanical hydraulic damper in the traditional tuned mass damper and relatively reduce the physical mass of the mass block. This solves the problems of the large mass block mass of the existing tuned mass damper, the use of mechanical hydraulic damping elements, resulting in high manufacturing costs, and the large load that the mass block will place on the controlled structure.

[0066] Meanwhile, this scheme uses a combination of elastic elements and oscillating plates. By adjusting the stiffness of the elastic elements and the size of the oscillating plates, the tuning frequency ratio and tuning damping ratio of this scheme can be made close to the optimal frequency ratio and optimal damping ratio, respectively. This reduces the design difficulty of this scheme and makes it easier for the vibration reduction performance of this scheme to approach the optimal value.

[0067] 2. The liquid tuned mass damper design method of this scheme, applied to a liquid tuned mass damper of this invention, involves first determining the total mass ratio Ω, and then determining the optimal frequency ratio ν based on the total mass ratio Ω and the external load amplitude ratio f. opt and optimal damping ratio γ opt Then through the optimal damping ratio

[0068] γ opt Determine the size of the oscillator plate, and finally use v opt and C m The order of determining the stiffness of elastic elements can be obtained experimentally to obtain the most realistic possible C. m It also participates in the calculation of the elastic element stiffness, thereby making the calculated elastic element stiffness as close as possible to the optimal value, and thus making the tuning frequency ratio of the liquid tuned mass damper designed in this scheme as close as possible to v. opt And achieve the best vibration reduction performance. Attached Figure Description

[0069] Figure 1This is a front view schematic diagram of the liquid tuned mass damper in Example 1 installed on a bridge;

[0070] Figure 2 This is a front view schematic diagram of the liquid tuned mass damper in Example 2 installed on a floating platform;

[0071] Figure 3 This is a flowchart illustrating the design method of the liquid tuned mass damper in Example 3;

[0072] Icons: 1-Mass block; 2-Elastic element; 3-Oscillating plate; 4-Limiting mechanism; 5-Connecting rod; 6-Protective sleeve. Detailed Implementation

[0073] The present invention will now be described in detail with reference to the accompanying drawings.

[0074] To make the objectives, technical solutions, and advantages of this invention clearer, the 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 and not intended to limit the invention.

[0075] Example 1

[0076] like Figure 1 As shown, the liquid tuned mass damper used in this embodiment includes a mass block 1, an elastic element 2, and an oscillating plate 3; one end of the elastic element 2 can be connected to the controlled structure, and the mass block 1 is connected to the other end of the elastic element 2; the oscillating plate 3 is connected to the mass block 1; the oscillating plate 3 and the elastic element 2 have an angle in their extension and contraction directions; the oscillating plate 3 can be immersed in the fluid.

[0077] Specifically, the controlled structure in this embodiment is a bridge, with a natural river flowing beneath it. If there is no natural river or lake beneath the bridge, an artificial fluid source is required, such as constructing a water tank beneath the bridge. In this embodiment, a liquid tuned mass damper is installed in the box girder of the bridge, wherein the mass block 1 is connected to the top surface of the box girder of the bridge via an elastic element 2. The elastic element 2 is specifically a helical spring, with its axis arranged vertically, enabling the mass block 1 and the oscillating plate 3 to vibrate vertically, thereby controlling the vertical vibration of the bridge. The elastic element 2 comprises two sets, which are symmetrically arranged relative to the centerline of the bridge.

[0078] The oscillation plate 3 is a square plate, specifically made of PVC material; for example... Figure 2 As shown, the direction a2 of the oscillating plate 3 forms an angle α with the axis a1 of the elastic element 2, specifically, α = 90°, meaning the oscillating plate 3 is arranged horizontally; since the mass block 1 is located in the box girder of the bridge in this embodiment, and is relatively far from the fluid below the bridge, therefore... Figure 1As shown, in this embodiment, the oscillating plate 3 is connected to the bottom surface of the mass block 1 by multiple connecting rods 5, so that the oscillating plate 3 can be immersed in the fluid under the bridge; diagonal braces are also provided between adjacent connecting rods 5 to ensure the reliability of the connection between the oscillating plate 3 and the mass block 1; the bottom of the box girder has openings corresponding to the connecting rods 5 to avoid obstructing the movement of the oscillating plate 3.

[0079] A limiting mechanism 4 is also provided on the bridge to restrict the mass block 1 to move only relative to the controlled structure along the extension and retraction direction of the elastic element 2. Specifically, the limiting mechanism 4 in this embodiment is a pulley mechanism, which is set in the opening at the bottom of the box girder corresponding to the connecting rod 5, so as to guide the up and down movement of the connecting rod 5, thereby restricting the mass block 1 and the oscillating plate 3 to move only up and down.

[0080] Example 2

[0081] like Figure 2 As shown, the liquid tuned mass damper used in this embodiment includes a mass block 1, an elastic element 2, and an oscillating plate 3; one end of the elastic element 2 can be connected to the controlled structure, and the mass block 1 is connected to the other end of the elastic element 2; the oscillating plate 3 is connected to the mass block 1; the oscillating plate 3 and the elastic element 2 have an angle in their extension and contraction directions; the oscillating plate 3 can be immersed in the fluid.

[0082] Specifically, the controlled structure in this embodiment is a floating platform, with an ocean or lake below it as a fluid. The liquid tuned mass damper in this embodiment is installed on the bottom surface of the float support of the floating platform, wherein the mass block 1 is connected to the bottom surface of the float support through an elastic element 2. The elastic element 2 is specifically a helical spring, whose axis is arranged in the vertical direction, so that the mass block 1 and the oscillating plate 3 can vibrate up and down in the vertical direction, thereby controlling the vertical vibration of the floating platform.

[0083] Since the mass block 1 and the elastic element 2 in this embodiment are located on the bottom surface of the float support and below the water surface, a protective sleeve 6 is also provided on the outside of the mass block 1 and the elastic element 2; the mass block 1 and the elastic element 2 are both located inside the protective sleeve 6; the protective sleeve 6 is used to prevent fluid from contacting the elastic element 2 and the mass block 1; specifically, in this embodiment, the counterweight chamber on the bottom surface of the float support is used directly as the protective sleeve 6 to save costs; the bottom surface of the counterweight chamber is open to avoid obstructing the movement of the oscillating plate 3 and its associated structures.

[0084] The vibrating plate 3 is a square plate, specifically made of PVC material; the surface of the vibrating plate 3 and the elastic element 2 have an angle, specifically, the angle is ninety degrees, that is, the vibrating plate 3 is arranged horizontally.

[0085] Example 3

[0086] like Figure 3As shown, the design method of a liquid tuned mass damper used in this embodiment, applied to a liquid tuned mass damper of the present invention, includes the following steps:

[0087] A. The initial mass m of mass block 1 is determined based on the vibration reduction requirements. T The additional mass coefficient C of the oscillating plate 3 m0 And obtain the total mass ratio Ω; based on the amplitude of the harmonic external load F0 and the stiffness k of the controlled structure. s The external load amplitude ratio f is obtained;

[0088] B. The optimal frequency ratio v of the liquid-tuned mass damper is obtained from the analytical formulas of Ω, f, and the optimal parameters. opt and optimal damping ratio γ opt ;

[0089] C. According to γ opt Determine the dimensions of the oscillating plate 3; experimentally measure the actual added mass coefficient C of the oscillating plate 3. m ;

[0090] D. According to v opt and C m Determine the stiffness of elastic element 2.

[0091] In step A, if higher vibration reduction performance is required, a larger value for m can be used. T and C m0 This results in a higher Ω; conversely, if cost reduction is required, a smaller m can be used. T and C m0 This reduces the size of mass block 1 and oscillating plate 3, thereby reducing costs;

[0092] Specifically, the formula for calculating Ω can be found in the following equation:

[0093] Ω=μ+β

[0094]

[0095]

[0096] In the formula, Ω is the total mass ratio, μ is the physical mass ratio, β is the added mass ratio, and m T Let m be the physical mass of block 1. s Let ρ be the mass of the controlled structure, ρ be the fluid density, L be the characteristic length of the oscillating plate 3, and C be the mass of the controlled structure. m0 To initially determine the additional mass coefficient; specifically, in this embodiment, L of the square oscillating plate 3 is the side length of the square.

[0097] The formula for calculating the external load amplitude ratio f can be found in the following formula:

[0098]

[0099] In the formula, f is the ratio of external load amplitude, F0 is the external load amplitude, and k s The stiffness of the controlled structure;

[0100] In step B, v is calculated according to the following formulas respectively. opt and γ opt :

[0101]

[0102]

[0103] Step C specifically includes the following steps:

[0104] C1, according to C m0 Several oscillating plates 3 of different sizes were fabricated; the additional damping ratio C of each oscillating plate 3 was measured through free vibration tests. d ;

[0105] C2, with C d With γ opt The closest size of the oscillating plate 3 is used as the size of the oscillating plate 3 in this embodiment.

[0106] In step D, the stiffness of elastic element 2 is calculated according to the following formula:

[0107]

[0108] In the formula, k T ρ is the stiffness of elastic element 2, ρ is the density of the fluid, L is the characteristic length of the oscillating plate 3, and ω is the stiffness of elastic element 2. s is the natural frequency of the controlled structure.

[0109] The above are merely preferred embodiments of the present invention and are 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 design method for a liquid tuned mass damper, applied to a liquid tuned mass damper, characterized in that: The liquid-tuned mass damper includes a mass block (1) and an elastic element (2), and also includes an oscillating plate (3); one end of the elastic element (2) can be connected to the controlled structure, and the other end of the elastic element (2) is connected to the mass block (1); the oscillating plate (3) is connected to the mass block (1); the surface of the oscillating plate (3) has an angle with the extension and contraction direction of the elastic element (2); the oscillating plate (3) can be immersed in the fluid; The design method for the liquid tuned mass damper includes the following steps: A. Determine the mass of the mass block (1) based on the vibration reduction requirements. and the additional mass coefficient of the oscillating plate (3) And obtain the total mass ratio According to the amplitude of the simple harmonic external load and the stiffness of the controlled structure Obtain the external load amplitude ratio ; and The calculation formulas are as follows: In the formula, The ratio of total mass. The ratio of physical mass. For the additional mass ratio, Let be the physical mass of the mass block. For the quality of the controlled structure, For fluid density, The characteristic length of the oscillating plate. To initially determine the additional mass coefficient; B. According to , The optimal frequency ratio of the liquid-tuned mass damper is obtained from the analytical formula of the optimal parameters. and optimal damping ratio ; C. According to The dimensions of the oscillating plate (3) are determined; the actual added mass coefficient of the oscillating plate (3) is experimentally measured. ; D. According to and Determine the stiffness of the elastic element (2).

2. The design method of a liquid tuned mass damper according to claim 1, characterized in that, The liquid tuned mass damper also includes a limiting mechanism (4); the limiting mechanism (4) is used to restrict the movement of the mass block (1) along the extension and retraction direction of the elastic element (2).

3. The design method of a liquid tuned mass damper according to claim 2, characterized in that, The limiting mechanism (4) includes a pulley; one end of the pulley is installed on the controlled structure; the other end of the pulley abuts against the mass block (1).

4. A design method for a liquid tuned mass damper according to any one of claims 1 to 3, characterized in that, The liquid-tuned mass damper also includes a protective sleeve (6); the mass block (1) and the elastic element (2) are both located inside the protective sleeve (6); the protective sleeve (6) is used to prevent fluid from contacting the elastic element (2) and the mass block (1).

5. A design method for a liquid tuned mass damper according to any one of claims 1 to 3, characterized in that, The elastic element (2) is a helical spring.

6. A design method for a liquid tuned mass damper according to any one of claims 1 to 3, characterized in that, The oscillating plate (3) is a PVC material component.

7. The design method of a liquid tuned mass damper according to claim 1, characterized in that, In step B, calculate according to the following formulas respectively. and : 。 8. The design method of a liquid tuned mass damper according to claim 1 or 7, characterized in that, Step C includes the following steps: C1, according to Several oscillating plates (3) of different sizes were fabricated; the additional damping ratio of each oscillating plate (3) was measured by free vibration test. ; C2, according to and The closest oscillating plate (3) determines the size of the oscillating plate (3).

9. A design method for a liquid tuned mass damper according to claim 1 or 7, characterized in that, In step D, the stiffness of the elastic element (2) is calculated according to the following formula: In the formula, It is the stiffness of the elastic element (2). For the density of the fluid, The characteristic length of the oscillating plate (3) is... The natural frequency of the controlled structure.

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