A semi-active tuned mass damper with adjustable stiffness and adjustable damping

Abstract

The application belongs to the technical field of structural vibration control, and discloses a semi-active tuned mass damper with adjustable stiffness and adjustable damping, wherein an adjustable damping element and an elastic element are connected in parallel to form an elastic-damping combined component, and the elastic-damping combined component is connected in series with another elastic element, so that the real-time continuous adjustment of the equivalent stiffness of the TMD is realized; meanwhile, the adjustable damping element is used to realize the adjustment of the equivalent damping. The damping element can be a magneto-rheological damper or a controllable liquid viscous damper, and the output damping force can be changed by applying current or adjusting the piston transmittance, respectively. The device does not need complex mechanical switching, has a large adjustment range, a fast response, low energy consumption, a simple structure, can adapt to the change of the inherent frequency of a structure and the demand of multi-modal vibration control, and can improve the vibration control effect.

Description

Technical Field

[0001] This invention belongs to the field of structural vibration control technology and relates to a semi-active tuned mass damper with adjustable stiffness and adjustable damping. Background Technology

[0002] A tuned mass damper (TMD) is a typical structural vibration control device widely used in buildings, bridges, and other flexible engineering structures to reduce the structural dynamic response caused by wind-induced vibration, human-induced vibration, seismic response, and other environmental excitations. A traditional TMD typically consists of a mass block, elastic elements, and damping elements, and its vibration reduction effect depends on the precise tuning between the device's natural frequency and the target vibration mode of the main structure.

[0003] However, in actual engineering service, the dynamic characteristics of a structure often change with environmental conditions, load levels, and usage status. For example, factors such as temperature changes, added mass effects, material nonlinearity, and aerodynamic effects can all cause the natural frequency of the structure to drift, thus causing traditional passive TMD to deviate from its optimal tuning state and significantly reduce its vibration reduction performance.

[0004] Furthermore, the vibration response of actual engineering structures typically exhibits significant multimodal characteristics. Taking long-span bridges and highly flexible structures as examples, their wind-induced vibration and seismic response often involve multiple modes, and the dominance of different modes may vary under different operating conditions. Traditional passive TMDs with single-frequency tuning struggle to simultaneously address the vibration control requirements of multiple target modes, often resulting in effectiveness for one mode but insufficient control for others. Therefore, semi-actively tuned mass dampers with adjustable parameters and the ability to adapt to multiple operating conditions and multiple modes have become an important research direction in the field of structural vibration control.

[0005] Among existing semi-actively tuned mass damper (TMD) technologies, the implementation of adjustable damping is relatively mature. By introducing intelligent damping elements such as magnetorheological dampers and controllable fluid viscous dampers, continuous or stepped adjustment of the damping force can be achieved under conditions of low energy consumption and good stability, thereby effectively improving the adaptability and robustness of the TMD under different operating conditions. Therefore, adjustable damping semi-actively tuned mass dampers have been extensively studied and verified in engineering applications and academic research.

[0006] In contrast, the research and engineering application of adjustable stiffness semi-active tuned mass dampers are still in the development stage. Existing technologies mostly employ mechanical methods to achieve stiffness adjustment, such as changing the effective length of the spring, switching different combinations of elastic elements, or using tilting springs and changing their tilt angle to achieve stiffness adjustment within a limited range. These solutions typically suffer from insufficient real-time performance, complex structural forms, large size, and discrete or intermittent stiffness adjustment characteristics, making it difficult to meet the demands for rapid and continuous stiffness adjustment under complex dynamic environments. Furthermore, frequent mechanical switching processes may introduce additional friction and wear, reducing the long-term reliability and service stability of the device.

[0007] Existing research has attempted to replace the damping elements in traditional passive TMDs with adjustable damping elements. By adjusting the output characteristics of the damping elements in real time, equivalent positive or negative stiffness forces can be generated at the dynamic response level, thus realizing a semi-active tuned mass damper with adjustable stiffness. However, the equivalent stiffness adjustment range of such devices is usually quite limited, and as the equivalent stiffness adjustment range increases, a larger equivalent damping is often introduced, thereby affecting operating efficiency.

[0008] Therefore, there is an urgent need to propose a new technical solution with a simple structure, reasonable control method, and the ability to achieve real-time and continuous adjustment of the stiffness of a semi-active tuned mass damper within a large range while maintaining the safety and stability of semi-active control. This solution can make up for the shortcomings of existing semi-active tuned mass dampers in terms of stiffness adjustability and further improve their vibration control effect under complex working conditions and variable environmental conditions. Summary of the Invention

[0009] To address the problems of existing semi-active tuned mass dampers where stiffness adjustment relies on mechanical structure, lacks real-time performance, and has a limited adjustment range, this invention proposes a semi-active tuned mass damper with adjustable stiffness and adjustable damping. This device, while maintaining the safety and stability of the semi-active control system, achieves real-time, continuous, and independent adjustment of the equivalent stiffness and damping parameters of the TMD (tunable mass damper) through a reasonable combination of adjustable damping elements and elastic elements. This improves the vibration control effect of the device under complex working conditions and changing structural dynamic characteristics.

[0010] A semi-actively tuned mass damper comprises a mass subsystem, an elastic subsystem, and a damping subsystem. The mass subsystem is identical to that of a conventional TMD, and its mass is denoted as [mass]. The damping subsystem employs a magnetorheological damper or a controllable liquid viscous damper, whose viscous damping coefficient can be adjusted in real time, denoted as . (The horizontal line above the parameter indicates that the parameter is adjustable in real time); the elastic subsystem consists of two parts connected in series, the first part being the stiffness coefficient. The first part is an elastic element, and the second part is an elastic-damped composite member, consisting of a stiffness coefficient. Elastic elements and adjustable damping elements Parallel configuration. Adjusted in real time. This allows for the alteration of the dynamic characteristics of the elastic-damped composite component, thereby enabling real-time adjustment of the equivalent stiffness of the semi-active tuned mass damper; through real-time adjustment... It can realize real-time adjustable equivalent damping of semi-active tuned mass dampers.

[0011] The technical solution of this invention:

[0012] A semi-active tuned mass damper with adjustable stiffness and adjustable damping includes a mass block 1, a first damping element 2, a first elastic element 3, a second damping element 4, a second elastic element 5, a connecting element 6, and a limiting element 7.

[0013] Mass block 1 is used to provide tuning mass. It is connected to the controlled main structure through an elastic subsystem and a damping subsystem, and mass block 1 can generate relative motion with respect to the controlled main structure in a predetermined direction.

[0014] The first damping element 2 is disposed between the mass block 1 and the controlled main structure, and serves as the damping subsystem of the semi-active tuned mass damper. Its viscous damping coefficient can be adjusted in real time.

[0015] The first elastic element 3, the second damping element 4, and the second elastic element 5 together form an elastic subsystem and are disposed between the mass block 1 and the controlled main structure; wherein, the second damping element 4 and the second elastic element 5 are connected in parallel to form an elastic-damping combined component, and the elastic-damping combined component is arranged in series with the first elastic element 3.

[0016] The connecting element 6 is disposed between the elastic-damping combined member and the first elastic element 3 to realize the connection between the two;

[0017] The limiting element 7 is used to limit the direction of motion of the mass block 1, prevent the mass block 1 from moving in an unexpected direction during vibration, and ensure the operational safety of the semi-active tuned mass damper.

[0018] Equivalent stiffness coefficient of semi-actively tuned mass damper and equivalent damping coefficient They are respectively:

[0019]

[0020] in, and These are the stiffness coefficients of the first elastic element 3 and the second elastic element 5, respectively. and These are the viscous damping coefficients of the first damping element 2 and the second damping element 4, respectively, and both are adjustable in real time. The steady-state vibration frequency of the controlled main structure;

[0021] The natural frequency of a semi-actively tuned mass damper Damping ratio They are respectively:

[0022]

[0023] in, The mass of mass block 1;

[0024] As can be seen from equation (1), by adjusting the viscous damping coefficient of the second damping element 4 in real time... This enables real-time adjustment of the equivalent stiffness coefficient of the semi-actively tuned mass damper; when At that time, the equivalent stiffness coefficient of the semi-actively tuned mass damper ;when At that time, the equivalent stiffness coefficient of the semi-actively tuned mass damper Therefore, the equivalent stiffness coefficient of the semi-active tuned mass damper is in arrive Continuous adjustment is achieved between them; when At that time, the equivalent stiffness coefficient of the semi-actively tuned mass damper The adjustable range is arrive The natural frequency corresponding to the semi-actively tuned mass damper exist and The connection between them is adjusted; by increasing the size of the first elastic element 3 The second elastic element 5 The ratio between these two values ​​can further expand the equivalent stiffness coefficient of the semi-actively tuned mass damper. and the natural frequency of the semi-actively tuned mass damper The adjustable range.

[0025] As can be seen from equation (2), the viscous damping coefficient of the first damping element 2 is... Viscous damping coefficient of the second damping element 4 Changes in all these factors will affect the equivalent damping coefficient of the semi-actively tuned mass damper. This has an impact. Specifically, the viscous damping coefficient of the second damping element 4... The adjustment of stiffness and damping characteristics changes the equivalent damping characteristics of the system, and also causes a change in the equivalent stiffness coefficient. To avoid strong coupling between stiffness adjustment and damping adjustment, and to achieve independent and precise control of the damping parameters, the equivalent damping coefficient of the semi-active tuned mass damper is mainly adjusted by regulating the viscous damping coefficient of the first damping element 2. accomplish.

[0026] The material and structure of the mass block 1 are not limited, and the mass size can be set according to the mass of the controlled structure and the vibration control requirements.

[0027] The first damping element 2 can be an adjustable damping element such as a magnetorheological damper or a controllable liquid viscous damper. The viscous damping coefficient can be adjusted under the action of an external control signal. If it is a magnetorheological damper, the adjustment is achieved by applying current. The larger the current, the greater the output damping force of the magnetorheological damper at a given speed, and the corresponding viscous damping coefficient also increases. If it is a controllable liquid viscous damper, the adjustment is achieved by changing the piston porosity. The smaller the porosity, the greater the damping force, and the corresponding viscous damping coefficient also increases.

[0028] The first elastic element 3 can be a helical tension spring or a helical compression spring, preferably made of spring steel wire, and preferably has a circular cross-sectional shape.

[0029] The second damping element 4 can be an adjustable damping element such as a magnetorheological damper or a controllable liquid viscous damper, and the viscous damping coefficient can be adjusted under the action of an external control signal.

[0030] The second elastic element 5 can be a helical tension spring or a helical compression spring, preferably made of spring steel wire, and preferably has a circular cross-sectional shape.

[0031] The connecting element 6 should have sufficient rigidity, strength and durability, and its material and structural form are not specifically limited.

[0032] The limiting element 7 should have sufficient rigidity, strength and durability, and its material and structural form are not specifically limited.

[0033] The beneficial effects of the present invention include: (1) By rationally combining adjustable damping elements and elastic elements, the real-time and continuous adjustment of the TMD equivalent stiffness and equivalent damping parameters is achieved without relying on complex mechanical structures or frequent mechanical switching; (2) The stiffness adjustment is achieved by adopting a semi-active control method, the energy consumption during the operation of the device is low, and no external energy is input to the controlled main structure, ensuring the safety and stability of the system operation; (3) The stiffness adjustment range is large, which can adapt to the large changes in the vibration frequency of the main structure and the multi-mode vibration control requirements; (4) The device has a simple structure, the control strategy and control algorithm are easy to implement, and it has good engineering feasibility. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the theoretical model of a semi-active tuned mass damper used for horizontal vibration control.

[0035] Figure 2 This is a schematic diagram of the theoretical model of a semi-active tuned mass damper used for vertical vibration control.

[0036] In the figure: 1 mass block, 2 first damping element, 3 first elastic element, 4 second damping element, 5 second elastic element, 6 connecting element, 7 limiting element. Detailed Implementation

[0037] The specific embodiments of the present invention will be described in detail below with reference to the technical solutions and accompanying drawings.

[0038] like Figure 1 and Figure 2 As shown, a semi-active tuned mass damper with adjustable stiffness and adjustable damping includes a mass block 1, a first damping element 2, a first elastic element 3, a second damping element 4, a second elastic element 5, a connecting element 6, and a limiting element 7.

[0039] Mass 1 is used to provide a tuned mass, which is connected to the controlled main structure through an elastic subsystem and a damping subsystem, and mass 1 is capable of relative motion with respect to the controlled main structure in a predetermined direction.

[0040] The first damping element 2 is disposed between the mass block 1 and the controlled main structure, serving as the damping subsystem of the semi-active tuned mass damper, and its viscous damping coefficient can be adjusted in real time.

[0041] The first elastic element 3, the second damping element 4, and the second elastic element 5 together form an elastic subsystem, which is disposed between the mass block 1 and the controlled main structure. Among them, the second damping element 4 and the second elastic element 5 are connected in parallel to form an elastic-damping combined component, which is arranged in series with the first elastic element 3.

[0042] The connecting element 6 is disposed between the elastic-damping composite member and the first elastic element 3 to achieve a reliable connection between the two.

[0043] The limiting element 7 is used to limit the direction of movement of the mass block 1, preventing the mass block 1 from moving in an unexpected direction during vibration, thereby ensuring the operational safety of the device.

[0044] Semi-active tuned mass dampers can be used for horizontal or vertical vibration control, and their theoretical models are illustrated as follows: Figure 1 and Figure 2 As shown.

[0045] Equivalent stiffness coefficient of elastic subsystem The equivalent damping coefficient of the damping subsystem They are respectively:

[0046]

[0047] in, and These are the stiffness coefficients of the first elastic element 3 and the second elastic element 5, respectively. and The damping coefficients of the first damping element 2 and the second damping element 4 are adjustable in real time. The steady-state vibration frequency of the controlled main structure is given by .

[0048] The natural frequency of a semi-actively tuned mass damper Damping ratio They are respectively:

[0049]

[0050] in, Let be the mass of mass block 1.

[0051] The above description is merely a preferred embodiment of the present invention and should not be considered as any limitation thereof. Any equivalent changes, modifications, or improvements made by those skilled in the art to the above embodiments when utilizing the technical solutions of the present invention should be considered as falling within the protection scope of the present invention.

Claims

1. A semi-active tuned mass damper with adjustable stiffness and adjustable damping, characterized in that, The semi-active tuned mass damper includes a mass block (1), a first damping element (2), a first elastic element (3), a second damping element (4), a second elastic element (5), a connecting element (6), and a limiting element (7). The mass block (1) is used to provide the tuning mass, which is connected to the controlled main structure through the elastic subsystem and the damping subsystem, and the mass block (1) can generate relative motion with respect to the controlled main structure in a predetermined direction. The first damping element (2) is set between the mass block (1) and the controlled main structure, and serves as the damping subsystem of the semi-active tuned mass damper. Its viscous damping coefficient can be adjusted in real time. The first elastic element (3), the second damping element (4) and the second elastic element (5) together form an elastic subsystem and are disposed between the mass block (1) and the controlled main structure; wherein, the second damping element (4) and the second elastic element (5) are connected in parallel to form an elastic-damping combined component, and the elastic-damping combined component is arranged in series with the first elastic element (3); The connecting element (6) is disposed between the elastic-damping composite member and the first elastic element (3) to realize the connection between the two; The limiting element (7) is used to limit the direction of motion of the mass block 1 and prevent the mass block (1) from moving in an unexpected direction during vibration. Equivalent stiffness coefficient of semi-actively tuned mass damper and equivalent damping coefficient They are respectively: in, and The stiffness coefficients of the first elastic element (3) and the second elastic element (5) are respectively; and These are the viscous damping coefficients of the first damping element (2) and the second damping element (4), respectively, and both are adjustable in real time. The steady-state vibration frequency of the controlled main structure; The natural frequency of a semi-actively tuned mass damper Damping ratio They are respectively: in, Let the mass of mass block (1) be denoted as .

2. The semi-active tuned mass damper with adjustable stiffness and adjustable damping according to claim 1, characterized in that, The first damping element (2) is a magnetorheological damper or a controllable liquid viscous damper.

3. The semi-active tuned mass damper with adjustable stiffness and adjustable damping according to claim 1, characterized in that, The first elastic element (3) and the second elastic element (5) are spiral tension springs or spiral compression springs, and their material is spring steel wire. The cross-sectional shape of the first elastic element (3) is circular.

4. The semi-active tuned mass damper with adjustable stiffness and adjustable damping according to claim 1, characterized in that, The second damping element (4) is a magnetorheological damper or a controllable liquid viscous damper.

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