Modeling of Tuned Liquid Damper With Submerged Nets

An analytical model for describing the effectiveness of tuned liquid damper (TLD) with submerged nets for suppressing horizontal vibration of structures is proposed. Dissipation energy due to the liquid motion under sinusoidal excitation is calculated based on nonlinear shallow water wave theory. In particular, the effects of hydraulic resistance produced by nets installed in a tank on the performance of TLDs are examined. The results of dissipation energy theoretically obtained are confirmed by experiments. To show the effectiveness of the proposed analytical model for TLD-structure interaction problems, the case in which TLD with nets is installed on top of a pylon of a cable-stayed bridge is described and the calculated results are compared with the actual experimental data. In the calculation, it is shown that the optimal damping factor, as is the case for tuned mass dampers (TMD), can be produced by the nets, and the effectiveness of TLD with nets are demonstrated.

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Modeling of Deepwater-Type Rectangular Tuned Liquid Damper With Submerged Nets

Journal of Pressure Vessel Technology ◽

10.1115/1.2883724 ◽

1999 ◽

Vol 121 (4) ◽

pp. 413-422 ◽

Cited By ~ 22

Author(s):

S. Kaneko ◽

O. Yoshida

Keyword(s):

Hydrodynamic Force ◽

Wave Theory ◽

Finite Amplitude ◽

Tuned Liquid Damper ◽

Damping Force ◽

Dissipation Energy ◽

Actual Structure ◽

High Rise ◽

Modeling Methodology ◽

Liquid Depth

An analytical model for describing the effectiveness of deepwater-type tuned liquid damper (TLD) with submerged nets for suppressing horizontal vibration of structures is proposed. TLD is a damping device for suppressing the vibration of long-period structures such as high-rise buildings, tall towers, the pylons of cable-stayed bridges, and so on. The damping force is created by the hydrodynamic force caused by the sloshing of water contained in rectangular tanks located on top of such structures. In this study, we proposed the dynamical model for analyzing deepwater-type TLD (DTLD) where the liquid depth is deep compared with the length of the rectangular tank. In particular, the effect of hydraulic resistance produced by submerged nets installed in the tank is examined intensively. In the analysis of DTLD, employing finite amplitude wave theory, we obtained the hydrodynamic force and the dissipation energy by using Galerkin method, taking the effect of submerged nets into account. The calculated results thus obtained are compared with experimental results, by which the validity of the modeling methodology is confirmed. Finally, the case in which DTLD with nets is installed on an actual structure is investigated both theoretically and experimentally and the performance of DTLD is illustrated.

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Pylons of cable-stayed bridges: a comparison

Canadian Journal of Civil Engineering ◽

10.1139/l88-071 ◽

1988 ◽

Vol 15 (4) ◽

pp. 516-523 ◽

Cited By ~ 2

Author(s):

Fakhry Aboul-Ella

Keyword(s):

Key Words ◽

Static Analysis ◽

Analytical Model ◽

Soil Structure ◽

Soil Mechanics ◽

Soil Structure Interaction ◽

Structure Interaction ◽

Cable Stayed Bridge ◽

Fixed Base ◽

Cable Stayed Bridges

A new analytical model for the static analysis of cable-stayed bridges is presented taking into consideration the effect of soil–structure interaction. Bridges having pylons and piers of different degrees of restraint, such as fixed or hinged base pylons, fixed base piers, and pile-supported piers, are analyzed and compared to investigate the effect of these restraints on the response of the entire cable-stayed bridge system. The validity of the assumption of fixed support for pylons or piers is also examined. Key words: bridges, cables, foundation, towers, pylons, piers, piles, caissons, soil mechanics.

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Study on human-induced vibration of a cable-stayed bridge without backstays located in abrupt valley

Advances in Structural Engineering ◽

10.1177/13694332211020397 ◽

2021 ◽

pp. 136943322110203

Author(s):

Yanru Wu ◽

Junxin Li ◽

Qing Sun

Keyword(s):

Empirical Formula ◽

Dynamic Instability ◽

Vertical Vibration ◽

Comfort Level ◽

Tuned Mass Dampers ◽

Dynamic Simulations ◽

Maximum Acceleration ◽

Cable Stayed Bridge ◽

Crowd Density ◽

Lateral Modes

This research aims to assess the pedestrian comfort and to control human-induced vibration of an arch tower cable-stayed bridge without backstays located in canyon. Dynamic simulations of human-induced vibration were carried out with a mode-by-mode approach, and the results indicated that a total of seven lateral and vertical modes of the bridge may suffer from excessive vibrations at the design crowd density. Based on the periodic walking force, the structure response under pedestrian loads was evaluated performing dynamic analyses with two Finite Element models of the footbridge. A single tuned mass damper (STMD) control system was developed for control of human-induced vibration, which consisted of four tuned mass dampers mounted on the mid-span of bridge to enhance damping ratios of lively modes. The results indicate that the maximum acceleration for the first-order lateral and second-order vertical vibration at the design crowd density exceed the associated threshold values referring to the comfort level 1 (CL1) Criteria. The critical pedestrian number of lateral dynamic instability estimated by the Dallard’s empirical formula is much smaller than the dynamic design pedestrian number; and the Dallard’s empirical formula is applicable to estimate the critical pedestrian number of lateral dynamic instability for this bridge by comparing with Pedroe Inês footbridge. The damping ratios for both the vertical and lateral modes increase appreciably after installing the tuned mass dampers and no evidence of large-amplitude vibrations has been observed, leading to the realization of satisfactory comfort levels, which can provide reference for vibration reduction design of this kind of bridge.

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Effect of Pile-Soil-Structure Interaction on the Cable-Stayed Bridge in Response to the Earthquake

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.539.731 ◽

2014 ◽

Vol 539 ◽

pp. 731-735 ◽

Cited By ~ 1

Author(s):

Yu Chen

Keyword(s):

Finite Element ◽

Seismic Response ◽

Soil Structure ◽

Response Spectrum ◽

Three Dimensional ◽

Soil Structure Interaction ◽

Structure Interaction ◽

Finite Element Software ◽

Cable Stayed Bridge ◽

Three Dimensional Finite Element

In this thesis, based on the design of a 140+90m span unusual single tower and single cable plane cable-stayed bridge, free vibration characteristics and seismic response are investigated; three dimensional finite element models of a single tower cable-stayed bridge with and without the pile-soil-structure interaction are established respectively by utilizing finite element software MIDAS/CIVIL, seismic response of Response spectrum and Earthquake schedule are analyzed respectively and compared. By the comparison of the data analysis, for small stiffness span cable-stayed bridge, the pile-soil-structure interaction can not be ignored with calculation and analysis of seismic response.

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