Double air chamber liquid gas mixed damping vertical TLCD control device and design method

Abstract

The application discloses a double-air-chamber liquid-air mixed damping variable cross-section vertical TLCD control device which is composed of a sealed U-shaped pipe, an air damping hole plate, a liquid damping hole plate and tuning liquid. The liquid damping hole plate is arranged at the joint of the horizontal pipe and the vertical pipe. When the liquid column flows through the throttle hole in the shaking process, water head loss is generated, and liquid damping energy consumption is realized. The air damping hole plate is installed on the upper end of the two vertical pipes and is sealed by a cover plate to form a double-air-chamber structure, so that the upper part of the vertical pipe forms two upper and lower gas chambers. When the liquid column moves to cause the gas in the chamber to flow and compress, additional damping force is generated in the process that the gas flows through the hole plate. The application also discloses a design method of the device. The application improves the geometric structure and liquid distribution ratio of the traditional TLCD for controlling horizontal load, realizes vibration control under the action of vertical load of the structure, and is especially suitable for reducing the vertical vibration of a large-span structure and significantly improving the comfort and safety of the structure.

Description

Technical Field

[0001] This invention relates to the field of civil engineering, and more particularly to a vertical vibration control device and design method for large-span building and bridge structural systems. Background Technology

[0002] Long-span structures are widely used in various major infrastructure projects, such as stadiums, airport terminals, and suspension bridges. These structures have not only become important landmarks in modern cities but have also significantly promoted the coordinated development of regional economies and urban functions. However, long-span structures typically possess inherent characteristics such as large spans, light weight, and low damping, making them highly susceptible to significant vibration responses under external dynamic loads (such as crowd loads and wind loads). Such vibrations not only affect the normal use of the structure and the comfort of personnel but, if the vibrations are continuous or excessive in amplitude, may also lead to fatigue damage to components and even jeopardize the overall safety and durability of the structure.

[0003] The tuned liquid column damper (TLCD) is a U-shaped tubular tuned liquid damper (TLD) that applies control force through the regular movement of liquid within horizontal and vertical tubes, and utilizes a small orifice in the horizontal tube to generate damping force. This effectively overcomes the nonlinear characteristics and low effective mass issues of TLDs during large-amplitude swaying. In recent years, TLCDs have been widely applied in research fields such as high-rise buildings, long-span bridges, and offshore platforms. However, a drawback of TLCDs is their limited frequency tuning parameters and primary applicability to low-frequency structures, as their natural frequency depends only on the total length of the liquid within the horizontal and vertical tubes. Therefore, TLCD faces challenges in structural applications with high fundamental frequencies, requiring a shorter liquid length, which makes it difficult to effectively exert its vibration reduction effect. Currently, TLCD devices are mainly used for horizontal vibration control of structures, and are particularly suitable for reducing wind-induced vibrations in high-rise buildings. Summary of the Invention

[0004] The technical problem to be solved by the embodiments of the present invention is to provide a vertical control device for a large-span structure with dual-chamber liquid-gas mixing damping variable cross-section TLCD, which can effectively control different types of vertical vibrations in a large-span structure system by improving the geometric structure and the proportion of liquid length distribution on the basis of the traditional TLCD.

[0005] To address the aforementioned technical problems, this invention provides a dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device, comprising a double-ended sealed U-shaped tube, a first air damping orifice plate, a second air damping orifice plate, a first liquid damping orifice plate, a second liquid damping orifice plate, and a tuning liquid. The U-shaped tube includes two vertical tubes on the left and right sides and a horizontal tube. The first liquid damping orifice plate and the second liquid damping orifice plate are respectively disposed at the connection between the vertical tube and the horizontal tube. The first air damping orifice plate and the second air damping orifice plate are respectively disposed on the upper air column portion of the two vertical tubes, forming two gas chambers. The tuning liquid fills the U-shaped tube, and the two vertical tubes generate a liquid level difference through air pressurization to provide vertical inertial force.

[0006] Furthermore, the ratio of the cross-sectional area of ​​the horizontal pipe to that of the vertical pipe ranges from 0.8 to 1.2.

[0007] Furthermore, the ratio of the opening area of ​​the first air damping orifice plate, the second air damping orifice plate, the first liquid damping orifice plate, and the second liquid damping orifice plate is 40%-60%.

[0008] Furthermore, the ratio of the height difference between the liquid levels in the two vertical pipes to the total length of the liquid is in the range of 0.8-0.9.

[0009] Furthermore, the top of the two vertical pipes is provided with a water flow hole and an air valve mounting hole.

[0010] Accordingly, this invention also provides a design method for a dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device. The structural parameters of the aforementioned dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device are designed using the following method:

[0011] S1: Analyze the structure by establishing a structural model using finite element software, and calculate the mass and low-order frequencies of the controlled structure.

[0012] S2: Calculate the mass of the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device using the following formula. Stiffness and damping coefficient :

[0013]

[0014]

[0015]

[0016] in, and These represent the optimal frequency ratio and optimal damping ratio of the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device and the controlled structure, respectively. This is the mass ratio, which is equal to the ratio of the mass of the dual-chamber liquid-gas mixing damped variable cross-section vertical TLCD control device to the mass of the first-order mode of the controlled structure. It is typically taken as 0.01-0.05. and These represent the first-order modal mass and first-order frequency of the structure, respectively.

[0017] S3: Determine the total length of the liquid in the vertical TLCD control device with dual-chamber liquid-gas mixing damping based on the following formula. Vertical pipe liquid level difference and horizontal pipe length :

[0018]

[0019]

[0020] in, For the lower liquid level height in the vertical pipe, This represents the cross-sectional area of ​​the vertical pipe. This is the cross-sectional area of ​​the horizontal pipe;

[0021] S4: Calculate the initial pressure value of the gas chamber in the vertical pipe on the low liquid level side using the following formula. Initial pressure value of the gas chamber in the vertical tube on the side with the higher liquid level :

[0022]

[0023]

[0024]

[0025] in, It is a variable index. , These are the distances between the first air damping orifice plate and the lower liquid level, and the distances between the second air damping orifice plate and the higher liquid level, respectively. It is the natural angular frequency.

[0026] It also includes S5: placing the first air damping orifice plate and the second air damping orifice plate in the middle of the air cavity, and with a total height of The relationship formula yields the distance between the first air damping orifice plate and the lower liquid level. The distance between the second air damping orifice plate and the higher liquid level .

[0027] It also includes S6: when the calculated gas pressure cannot be achieved in engineering, change the parameter values ​​including the height of the sealing column, the cross-sectional area ratio, and the liquid density, and repeat the process of S3-S4 above.

[0028] Implementing the embodiments of this invention has the following beneficial effects: This invention improves upon the geometry and liquid distribution ratio of traditional TLCDs, enabling vibration control under vertical loads. It is particularly suitable for reducing vertical vibrations in large-span structures caused by pedestrians, vehicles, and wind loads, significantly improving structural comfort and safety. This invention features a simple structure, low cost, and significant damping effect. Building upon the traditional head loss energy dissipation mechanism, it further introduces additional head loss due to variable cross-section corners and air damping energy dissipation mechanisms, expanding its energy dissipation pathways. Simultaneously, the device provides a rich set of frequency tuning parameters (such as liquid density, air pressure, and cross-sectional area ratio) to handle various structural systems, possessing wide-band vibration reduction capabilities, and is particularly suitable for parameter optimization of already installed structures. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device of the present invention;

[0030] Figure 2 This is a plan view of the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device of the present invention;

[0031] Figure 3 This is a diagram of a vertical TLCD coupling model of a crowd-large-span structure-single-chamber structure;

[0032] Figure 4 It is a single-chamber vertical TLCD with different mass ratios installed on the floor slab under the action of single-person synchronous walking. / Normalized acceleration response under ( )

[0033] Figure 5 It is a comparison of the acceleration response before and after the installation of a single-chamber vertical TLCD on the floor slab under the action of 20 people walking simultaneously. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.

[0035] The first aspect of this invention provides a vertical control device for a large-span structure, a dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD, such as... Figure 1 and Figure 2As shown, the system includes a double-sealed U-shaped tube, a first air damping orifice plate 110, a second air damping orifice plate 110b, a first liquid damping orifice plate 113, a second liquid damping orifice plate 113b, and a tuning liquid 109. The U-shaped tube includes two vertical tubes on the left and right sides and a horizontal tube. The two vertical tubes are connected by U-shaped plates 101 and their tops are sealed by U-shaped plate end caps 102. The horizontal tube is formed by U-shaped plates 103 and 104 connected on four sides, and its top and bottom are sealed by U-shaped plates 105 and 106, respectively. The first liquid damping orifice plate 113 and the second liquid damping orifice plate 113b... The first air damping orifice plate 110 and the second air damping orifice plate 110b are respectively set at the connection between the vertical pipe and the horizontal pipe, and are respectively set in the upper air part of the two vertical pipes to form an upper gas chamber 111 and a lower gas chamber 112. The end cover plate 102 of the U-shaped plate is provided with a water injection hole 107 and an air valve mounting hole 108. The tuning liquid 109 is injected through the water injection hole 107, and pressurized air is input into one of the vertical pipes through the air valve mounting hole 108 to generate a liquid level difference.

[0036] In this embodiment, the height difference of the liquid level in the vertical pipe ( ) accounts for ( ) of the total length of the liquid For most of the components, the optimized reference value is between 0.8 and 0.9, while the length of the liquid column in the vertical tube (the lower liquid level height in the vertical tube) is... - The height of the horizontal pipe should be at least half of the horizontal pipe height and the greater of the liquid sloshing displacement. The reference value for the ratio of the cross-sectional area of ​​the horizontal pipe to the vertical pipe should be between 0.8 and 1.2. The optimal opening ratio of the throttling orifice (the ratio of the cross-sectional area of ​​the orifice to the cross-sectional area of ​​the water pipe) should be between 0.4 and 0.6. The damping orifice plate can be installed in the middle of the gas chamber, dividing the single chamber evenly. The reference value for the opening area ratio of the damping orifice plate is recommended to be 40%.

[0037] If this embodiment is used in a high-frequency structure, the initial value of the cross-sectional area ratio of the horizontal tube and the vertical tube can be 0.8-1.0. If it is applied to a low-frequency structure, the initial value of the cross-sectional area ratio of the horizontal tube and the vertical tube can be 1.0-1.2.

[0038] In the test model of this embodiment, acrylic glass was chosen as the tubing material due to its good toughness and transparency, and it is widely used in test models of devices such as TLD, TLCD, and sealed TLCD. Although acrylic glass was used in this embodiment, materials such as iron, steel, or PVC can also be used to suit different practical needs.

[0039] The closed vertical tube structure at both ends of this embodiment provides greater air spring stiffness, making it suitable for higher frequency floor structure systems, such as the floor structure fundamental frequency requirement of GB50010-2010 "Code for Design of Concrete Structures," which generally requires a minimum of 3.0 Hz. The structure with one closed end, where only the air column within the sealed end dominates the air spring stiffness, is suitable for lower frequency structural systems, such as long-span pedestrian bridge structures. Furthermore, by evacuating and reducing the initial air pressure to negative pressure, its applicability to ultra-low frequency long-span suspension bridges and other structural types can be enhanced.

[0040] Water inlet 107 is used for liquid mass adjustment. Considering the high sealing requirements of dual-chamber liquid-gas mixing damping variable cross-section vertical TLCDs, especially in the testing of vertically sealed TLCDs, it is crucial to obtain the pressure change and displacement values ​​of the liquid during sloshing. This inlet is designed to be used for connecting an external digital pressure sensor. By fixing a hose connector, a hose is connected to the sensor connector (such as a nozzle type) to monitor the pressure inside the pipe.

[0041] The air valve mounting hole 108 is connected to an external air pump and other devices to adjust the air pressure in the pipe, thereby changing the height difference of different liquid levels in the vertical pipe. It is suitable for frequency adjustment of devices that have been installed on the structure.

[0042] Liquid density is also a key parameter for tuning frequency. In this example, low-cost pure water is used as the liquid, but other liquids with different densities or viscosities, such as water-ethanol mixtures, oils, or glycerin, can be selected as needed. The use of viscous liquids enhances energy dissipation during sloshing. Furthermore, the damping performance can be further improved by changing the shape of the pipe cross-section. This invention enhances the damping effect by designing a variable cross-section, utilizing the energy dissipation generated when the liquid flows through corners.

[0043] This embodiment is mainly used for vibration control of a single mode of structure, especially low-order modes that contribute significantly to the structural response. For multi-mode vibration control, it is similar to using multiple TMDs and multiple TLCDs. By combining multiple dual-chamber liquid-gas hybrid damping variable cross-section vertical TLCD units, multiple tuning parameters (such as in-tube air pressure, liquid length, cross-sectional area ratio, etc.) are fully utilized to achieve control of multiple modes of the structure, thereby improving the robustness and control effect of the dual-chamber liquid-gas hybrid damping variable cross-section vertical TLCD.

[0044] The second aspect of this invention provides a design method for a dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device, which designs the structural parameters of the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device of the first aspect.

[0045] S1: In terms of structural control design, based on the modal parameters (frequency, mode shape, and mass) of the controlled structure, the optimization parameter design method proposed by Den Hartog can be applied to design the parameters (mass) of the vertical TLCD of the double-chamber variable cross-section liquid-gas hybrid damping. Stiffness and damping coefficient For determining the modal parameters such as frequency and mode shape of the controlled structure, low-order modes are usually the primary focus. A common method is to establish a structural model using finite element software and perform modal analysis on the structure to automatically calculate the mass, low-order frequencies, and mode shapes of the controlled structure.

[0046] S2: Calculate the mass of the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device using the following formula. Stiffness and damping coefficient :

[0047]

[0048]

[0049]

[0050] in, and This represents the optimal frequency ratio and optimal damping ratio between the dual-chamber liquid-gas mixing damped variable cross-section vertical TLCD control device and the controlled structure. This is the mass ratio, which is equal to the ratio of the mass of the dual-chamber liquid-gas mixing damped variable cross-section vertical TLCD control device to the mass of the first-order mode of the controlled structure. It is typically taken as 0.01-0.05. and These represent the first-order modal mass and first-order frequency of the structure, respectively.

[0051] In the above:

[0052] ;

[0053] .

[0054] S3: Frequency Design

[0055] The initial values ​​of the structural parameters of the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device are set, including the initial cross-sectional area ratio of the horizontal tube and the vertical tube. / Length coefficient of vertical pipe liquid level difference The vertical pipe has a lower liquid level. and liquid density Based on experience, the following ratios are determined: for low-frequency structures, the initial ratio of the cross-sectional area of ​​the horizontal to vertical tubes can be 1.0-1.2; for high-frequency structures, the initial ratio can be 0.8-1.0. The length coefficient for the liquid level difference in the vertical tube can be 0.8-0.9. The liquid column height in the vertical tube should be at least half the height of the horizontal tube, i.e., the lower liquid level height in the vertical tube. The height should be at least 1.5 times that of the horizontal pipe; the tuning liquid is usually water, with a density of 1000 kg / m³. 3 .

[0056] The initial values ​​of the total height and the cross-sectional area of ​​the vertical tube of the dual-chamber liquid-gas hybrid damping variable cross-section vertical TLCD control device are determined based on the installation space constraints: if installed inside the controlled structure, the total height of the dual-chamber liquid-gas hybrid damping variable cross-section vertical TLCD must be less than the net height of that floor; the cross-sectional area of ​​the vertical tube is determined based on the horizontal projection dimensions of the reserved installation space. This ensures full utilization of the installation space to achieve the expected damper mass and inertial force design requirements.

[0057] The total length of the liquid in the vertical TLCD control device with variable cross-section and liquid-gas mixing damping in a dual-chamber configuration is determined according to the following formula. Vertical pipe liquid level difference and horizontal pipe length :

[0058]

[0059]

[0060] in, For the lower liquid level height in the vertical pipe, This represents the cross-sectional area of ​​the vertical pipe. This is the cross-sectional area of ​​the horizontal pipe;

[0061] With the damping orifice plate placed in the middle of the air cavity, the heights of the upper and lower air chambers of the left and right limbs are equal, and then the total height is calculated as follows. The relationship can be used to determine the height of the gas chamber in the left limb. and right lower extremity gas chamber .

[0062]

[0063] S4: Calculate the initial pressure value of the gas chamber in the vertical pipe on the low liquid level side using the following formula. Initial pressure value of the gas chamber in the vertical tube on the side with the higher liquid level :

[0064]

[0065]

[0066]

[0067] in, It is a variable index. , These are the distances between the first air damping orifice plate and the lower liquid level, and the distances between the second air damping orifice plate and the higher liquid level, respectively. It is the natural angular frequency.

[0068] When the calculated gas pressure is not a value that can be achieved in engineering, change the initial value of one parameter while keeping the other parameters unchanged, and repeat S3-S4 until the gas pressure can be achieved in engineering.

[0069] Check the time history results of the liquid in the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device to ensure that the liquid column water level of the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD is not lower than the water level of its horizontal section during the oscillation process.

[0070] The dual-chamber liquid-gas hybrid damping variable cross-section vertical TLCD of this embodiment is highly applicable to structures with different frequencies. This device has a rich set of frequency tuning parameters, including the pressure inside the sealing column, the height of the sealing column, the liquid density, and the cross-sectional area ratio. Through independent adjustment or coupled control of these parameters, the inherent frequency can be controlled, making it particularly suitable for post-installation frequency tuning scenarios. This effectively solves the technical pain points of traditional TLCD devices, such as "difficult frequency tuning after installation" and "narrow frequency adaptation range due to reliance on only the liquid length as a single frequency tuning parameter."

[0071] Specifically, before installation, parameters such as the initial pressure of the sealing column, the cross-sectional area ratio, the height of the sealing column, and the liquid density can be independently adjusted or coupled with multiple parameters to allow the device to flexibly adapt to structural systems with different frequency characteristics from low to high frequencies. After installation, if the fundamental frequency of the structure changes, there is no need to disassemble and adjust the main structure of the device. Simply by changing the initial pressure of the sealing column, the device's natural frequency can be quickly readjusted, ensuring continuous and efficient control of structural vibration.

[0072] Meanwhile, based on the traditional TLCD head loss energy dissipation mechanism, this device further introduces the additional head loss of the horizontal and vertical pipe cross-section corners and the small hole air damping energy dissipation mechanism, thereby expanding the energy dissipation path and improving the vibration reduction performance of this embodiment.

[0073] In this embodiment, the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device can be installed on the floor using methods such as bolt connection, welding connection, embedded part connection, concrete pouring connection, and bracket support connection. Bolt connection and welding connection directly fix the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD to the floor structure. Embedded part connection involves pre-embedding connectors in the floor structure during the construction phase, and then installing the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD onto the embedded parts. Concrete pouring connection involves installing the vertical TLCD inside the floor slab, with its base plate connected to the distributed reinforcing steel bars of the floor slab, and then pouring concrete. Bracket support connection uses brackets to support the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD on the floor; the brackets can be adjusted as needed to adapt to different installation positions and heights. Alternatively, a combination of bolts and brackets can be used to fix the dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD. By fixing the dual-chamber liquid-gas hybrid damping variable cross-section vertical TLCD to the first-order modal position of the controlled structure using the above installation method, when the structure (such as a tower) vibrates due to external excitation (such as earthquake or wind load), the dual-chamber liquid-gas hybrid damping variable cross-section vertical TLCD moves with the structure. The internal liquid sloshes due to inertia and gravity. At the same time, the head loss effect caused by the liquid sloshing through the throttling orifice, the head loss at the variable cross-section corner, and the damping effect generated when the gas flows through the air damping orifice plate are used to provide damping energy dissipation. Combined with the restoring force generated by the liquid sloshing, the vertical vibration response of the structure is reduced, and its vibration reduction efficiency is maximized.

[0074] This invention uses a representative dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD (damping orifice plate fully open, at this time, = =0, = = Taking this as an example, the structural parameter design method of the vertical TLCD with dual-chamber liquid-gas hybrid damping and variable cross-section according to the present invention will be explained. Under this specific parameter setting, the damping orifice is completely open and there is no damping effect. At the same time, the upper and lower air chambers are unobstructed and the air pressure is balanced, which is equivalent to the height of the air chambers on the left and right limbs. , The value is 0, and since the cross-sectional areas of the horizontal and vertical pipes are equal, both are 0. This makes the dual-chamber system functionally and structurally equivalent to a single-chamber vertical TLCD. Therefore, this example will use this equivalent single-chamber vertical TLCD model as the analysis object, selecting the third floor slab (maximum longitudinal span of 32 m) of a five-story integrated cultural and sports center as the analysis object. Considering the large span of this floor slab and the building's function as an exhibition hall, it is prone to comfort issues due to vibrations caused by people. Therefore, MATLAB numerical simulation is used to calculate the dynamic response of the structure before and after the installation of this equivalent single-chamber vertical TLCD under the action of single and multiple people walking synchronously.

[0075] (1) Pedestrian load simulation

[0076] like Figure 3 To simulate pedestrian loads, a common and simple Fourier series load model is adopted, and the load expression is as follows:

[0077]

[0078]

[0079]

[0080]

[0081] in, This indicates the pedestrian's weight, typically taken as 750 N; Walking frequency (Hz) For the first The first phase angle, usually taken as 0, (=1, 2, 3…) represents the harmonic numbers. The dynamic load factor is typically one of the first three orders. The loading time of pedestrian loads is determined by the walking speed and loading length. This is combined with the first-order frequency of the structure (…). Based on the requirements of 2.54 Hz and relevant specifications, the step frequency was set to 2.54 Hz to obtain a larger response. Secondly, the number of pedestrians to be loaded was determined; based on the structure's function and specifications, a crowd density of 0.34 people / m² was selected. 2 (Slightly denser), and based on the floor area (64) 39 m 2 The maximum number of pedestrians to be loaded was determined to be 60. Further designs were implemented with different numbers of pedestrians, including single-person, 20-person, and 40-person loads. Single-person excitation was used to verify the accuracy of the loading position, while multi-person excitation was used to simulate the actual structural dynamic response, revealing the influence of the single-chamber vertical TLCD on the structural dynamic response under different numbers of pedestrians.

[0082] The initial mass ratio was set at 0.02. Based on the modal parameters and optimization parameter design formulas of the structure, the mass, damping, and stiffness of the single-chamber vertical TLCD were determined sequentially to be 7300 kg, 3100 N, and so on. s / m and 1774500 N / m.

[0083] Considering that the vertical inertial force of the vertical TLCD mainly depends on the mass of the liquid due to the height difference in the vertical tube, five different mass ratios were designed ( / ), that is, the vertical height difference of the liquid mass ( ) and total mass of liquid ( The ratios of the vertical TLCD mass ratios were set to 0.0, 0.2, 0.4, 0.6, and 0.8 to verify the effectiveness of the single-chamber vertical TLCD-structure coupling equation and to investigate the contribution of the vertical tube height difference mass to vibration reduction performance. Taking single-person loading as the analysis object, the normalized peak acceleration response of the structure under different mass ratios in the single-chamber vertical TLCD was calculated using numerical simulation, as shown in the attached figure. Figure 4 As shown.

[0084] For a single-chamber vertical TLCD system, the expression for the natural angular frequency of the single-chamber vertical TLCD is as follows:

[0085]

[0086] The corresponding structure—the coupling matrix equation of a single-chamber vertical TLCD—can be expressed as:

[0087]

[0088] In the formula, , and These represent the mass, stiffness, and damping of the structure, respectively. , and These represent the acceleration, velocity, and displacement of the structure, respectively. This is the head loss coefficient.

[0089] The above equations of motion can be solved using conventional numerical integration algorithms. This invention takes the Newmark-β algorithm as an example to calculate the dynamic response of the structure before and after the installation of the vertical TLCD and the response of the vertical TLCD (both are acceleration, velocity and displacement relative to the ground).

[0090] From the appendix Figure 4 It can be seen that as the mass ratio ( / With the increase of mass ratio, the acceleration response of the structure decreases significantly. When the mass ratio is 0.0, i.e. there is no height difference in the liquid in the vertical tube, the vibration reduction effect is not obvious, and the vibration reduction rate is 1.75%. As the mass ratio increases from 0.0 to 0.6, the vibration reduction rate increases to 52.63%, which fully verifies the effectiveness of the vertical TLCD mechanical model and its vibration reduction performance.

[0091] A representative comparison of the acceleration response of structures with and without a single-chamber vertical TLCD was selected under the action of 20 people walking synchronously. (See...) Figure 5 (a) and 5(b) in the example.

[0092] Depend on Figure 5 As shown in (a), the time history curves of the structural acceleration response before and after the installation of the single-chamber vertical TLCD have a high degree of agreement, both conforming to the first-order vibration mode characteristics of the structure, i.e., the acceleration response gradually increases from the beginning, reaches a peak at about 10 s, and then gradually decreases. After the installation of the single-chamber vertical TLCD, the acceleration of the structure decreases significantly. Furthermore, from... Figure 5 As shown in (b), the dominant frequencies of the acceleration response are basically the same, which are the first-order frequencies of the structure. Moreover, the spectral values ​​at these frequencies are significantly reduced. The above results not only verify the accuracy of the loading, but also further verify that a good resonance was generated between the vertical TLCD and the structure.

[0093] Table 1 shows the peak acceleration and vibration reduction rate of the structure before and after the installation of the single-chamber vertical TLCD under different pedestrian loads. Based on the relevant specifications for the structure's function and comfort, the determined comfort limit is 0.15 m / s². 2 .

[0094] Table 1:

[0095]

[0096] According to the comparison in Table 1, under the action of single-person and multi-person synchronous walking, the acceleration response of the structure is significantly reduced after installing the single-chamber vertical TLCD. Under the action of 20 people walking synchronously, the peak acceleration of the floor slab decreases from 0.223 m / s². 2 Reduced to 0.126 m / s 2 This satisfies the comfort limit of 0.15 m / s specified in the standard. 2 Furthermore, the average vibration reduction rate under all loading conditions was 43.17%, which further verifies the rationality of the vertical TLCD parameter design and its contribution to the vibration reduction performance of large-span structures.

[0097] This embodiment demonstrates that the key parameter of the vertical tube height difference mass improves the vibration reduction performance of the device, and the device of the present invention can further improve the comfort of large-span structures under vertical loads.

[0098] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A dual-chamber liquid-gas mixing damping variable cross-section vertical TLCD control device, characterized in that, The system includes a double-sealed U-shaped tube, a first air damping orifice plate, a second air damping orifice plate, a first liquid damping orifice plate, a second liquid damping orifice plate, and a tuning liquid. The U-shaped tube comprises two vertical tubes (left and right) and a horizontal tube. The first and second liquid damping orifice plates are respectively disposed at the connection points of the vertical tubes and the horizontal tubes. The first and second air damping orifice plates are respectively disposed in the upper air sections of the two vertical tubes, forming two gas chambers, upper and lower. The tuning liquid is filled with... Within the U-shaped tube, two vertical tubes generate a liquid level difference through air pressurization; the cross-sectional area ratio of the horizontal tube and the vertical tube ranges from 0.8 to 1.2; the opening area ratio of the first air damping orifice plate, the second air damping orifice plate, the first liquid damping orifice plate, and the second liquid damping orifice plate is 40% to 60%; the ratio of the liquid length corresponding to the liquid level difference between the two vertical tubes to the total liquid length ranges from 0.8 to 0.9; and the tops of the two vertical tubes are provided with water flow holes and air valve mounting holes.

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