Longitudinal Vibration Control of Long-Span Railway Cable-Stayed Bridge

2011 ◽  
Vol 255-260 ◽  
pp. 1795-1799
Author(s):  
De Shan Shan ◽  
Yuan He ◽  
Li Qiao
Keyword(s):  
Vibration Control ◽  
Longitudinal Vibration ◽  
Time History ◽  
Bending Moment ◽  
Element Model ◽  
Viscous Dampers ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Two Parameters ◽  
Main Girder

As the floating type cable-stayed bridge has no longitudinal constraint between the main girder and the pylon, it may cause the main girder a large longitudinal displacement and the root of tower a large longitudinal bending moment, and affect the normal use and safety of the bridge under the earthquake or the train braking. It is an important part of the design to select an appropriate vibration control scheme. Taking a long-span railway bridge for example, this paper build the finite element model and analyses the damping effect in the view of train braking, moreover, the present study also examines the dynamic behavior with focus on two parameters of damping coefficient C and damping exponent αof the viscous dampers through dynamic time-history analysis. The results show that setting viscous dampers with the reasonable parameters can reduce the vibration and the response of the bridge by train braking and have a good energy dissipation effect.

Geometric Nonlinear Effect on Large Span Cable-Stayed Bridge

2014 ◽  
Vol 638-640 ◽  
pp. 942-946
Author(s):  
Shuang Rui Chen ◽  
Quan Sheng Yan
Keyword(s):  
Linear Method ◽  
Bending Moment ◽  
Nonlinear Effects ◽  
Element Model ◽  
Vertical Displacement ◽  
Displacement Effect ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Geometric Nonlinear ◽  
Main Girder

It is introduced that three main factors cause geometric nonlinear effects of long span cable-stayed bridge: large displacement effect, cable sag effect, and the combination of bending moment and axial force effect. The iteration method of geometrical nonlinear problem is also introduced. The bridge deformation was calculated by establishing a plane truss finite element model of a long-span single tower cable-stayed bridge under consideration of nonlinearity and compared with that done with linear method. It is concluded that nonlinearity influenced differently to the bending moment of main girder, the displacement of tower root and the vertical displacement of girder.

Based on Nonlinear Viscous Dampers Seismic Behavior Research of a Long Span Cable-Stayed Bridge

2011 ◽  
Vol 255-260 ◽  
pp. 1214-1219 ◽  
Author(s):  
Hong Yu Jia ◽  
Shi Xiong Zheng ◽  
Lei Yang ◽  
Ming Qiang Xia
Keyword(s):  
Seismic Behavior ◽  
Vertical Direction ◽  
Time History ◽  
Longitudinal Direction ◽  
Relative Displacement ◽  
Sensitivity Study ◽  
Damping Coefficient ◽  
Viscous Dampers ◽  
Long Span ◽  
Two Parameters

The seismic behavior research of Fengdu Bridge with nonlinear viscous dampers will be conducted to investigate two parameters of damping coefficient C and damping exponent ξ through nonlinear dynamic time-history analysis. Simultaneously, the analysis results are compared with the seismic response without viscous dampers and proposed control methods and formulas of a reasonable selecting damping coefficient C and damping exponent ξ are provided. The parameters sensitivity study indicates that setting dampers in longitudinal direction of bridge can reduce the relative displacement of key positions and the response of the bridge, the beneficial effect of the isolation in the longitudinal direction, but important amplification occurs in the vertical direction for relatively high frequency components. Moreover, the reference of application of nonlinear viscous damper will be provided for similar projects.

scholarly journals Seismic Response Mitigation of a Long-Span Tower Bridge with Two Types of Constraint System

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Li Xu ◽  
Qingfei Gao ◽  
Junhao Zheng ◽  
Chuanhui Ding ◽  
Kang Liu
Keyword(s):  
Element Model ◽  
Main Beam ◽  
Seismic Load ◽  
Viscous Damper ◽  
Viscous Dampers ◽  
Damping Effect ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Drift Frequency ◽  
Nonlinear Finite Element Model

The stress of the main tower of a cable-stayed bridge depends on the connection type between the tower and deck. In order to study the most suitable longitudinal damping mode for a long-span cable-stayed bridge. In this article, a nonlinear finite element model is established based on a large span concrete cable-stayed bridge with a main span of 680 m. Without considering the influence of the transverse constraint, the damping effect of the elastic connection device and the viscous damper is simulated when the longitudinal seismic load is input. The results show that the stiffness of the main beam is increased by installing the elastic connection device, so the longitudinal drift frequency of the main beam is increased, but the stiffness of the structure is not changed by installing the viscous damper. Both viscous dampers and elastic connection structures can reduce the longitudinal displacement of the beam end, but viscous dampers are more favorable for the stress of the main tower. In terms of damping effect, viscous dampers are more suitable for long-span cable-stayed bridges, but, in terms of economy and parameter control, elastic connection devices have more advantages.

scholarly journals Vibration response of railway cable-stayed bridges under high-speed train braking loads

2020 ◽  
Vol 165 ◽  
pp. 04053
Author(s):  
Long Lu
Keyword(s):  
High Speed ◽  
Longitudinal Vibration ◽  
Bending Moment ◽  
Vibration Response ◽  
Design Parameters ◽  
High Speed Train ◽  
Fluid Viscous Dampers ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Longitudinal Response

With the increase of the running speed of high-speed trains, the longitudinal vibration of the long span railway cable-stayed bridge under train loads has increased significantly. And the probability of high-speed train braking is greater than earthquake. The excessive vibration response will affect the serviceable of the cable-stayed bridge. Fluid viscous dampers (FVDs) and elastic cables (ECs) which are widely used in seismic design of the bridge are adopted to control the longitudinal vibration response of the cable-stayed bridge induced by train braking loads. The influence of the design parameters of FVDs and ECs on the response of the bridge is studied. And the effectiveness of FVDs and ECs on mitigating the longitudinal response of the bridge is also discussed. It is found that installing FVDs and ECs between the deck and the tower is very efficient in reducing the longitudinal vibration of the railway cable-stayed bridge subjected to train braking loads, especially the longitudinal displacement of the deck and the bending moment of the tower.

scholarly journals Seismic Response Reduction of Megaframe with Vibration Control Substructure

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Jun-Qi Huang ◽  
Xun Chong ◽  
Qing Jiang ◽  
Xian-Guo Ye ◽  
Han-Qin Wang
Keyword(s):  
Vibration Control ◽  
Seismic Response ◽  
Element Model ◽  
Viscous Dampers ◽  
Lead Rubber Bearings ◽  
Standard Value ◽  
Rubber Bearings ◽  
Rare Earthquake ◽  
Tuning Frequency ◽  
Two Parameters

Megaframe with vibration control substructure (MFVCS) is a tuned mass damper system, which converts the substructures into the tuned mass. In this study, a kind of MFVCS using both lead-rubber bearings and viscous dampers to connect the vibration control substructure with the megaframe was proposed. Then, based on a validated finite element model, a parametric analysis was conducted to study the effect of two parameters, the tuning frequency (i.e., the frequency of the substructure) and the damping provided by the lead-rubber bearings and viscous dampers on the seismic response reduction of the MFVCS under both frequent and rare earthquakes (i.e., probability of exceedance of 63% and 2% in 50 years, resp.). Furthermore, the optimized values of these two parameters were achieved. The results indicated that (1) the proposed MFVCS could provide a considerable seismic response reduction under frequent earthquake and showed a strong robustness; (2) the optimized values of the frequency ratio (ratio of tuning frequency to the megaframe’s natural frequency) and damping scale factor (ratio between the investigated damping and a standard value) were 0.96 and 1.0, respectively; and (3) the seismic response reduction of the MFVCS under rare earthquake was lower than that under frequent earthquake.

Study on Optimized Shock Absorption Design of a Floating Cable-Stayed Bridge

2013 ◽  
Vol 438-439 ◽  
pp. 874-878
Author(s):  
Sheng Ping Wu ◽  
Li Xu ◽  
Zhen Zheng Fang
Keyword(s):  
Time History ◽  
Bending Moment ◽  
Longitudinal Direction ◽  
Seismic Action ◽  
Viscous Dampers ◽  
Cable Stayed Bridge ◽  
Optimal Damping ◽  
Floating System ◽  
Longitudinal Bending ◽  
Dynamic Time

Floating system of cable-stayed bridges under seismic action will produce larger longitudinal bending moment and displacement, in order to ensure the safety of the structure, damping measures should be taken in longitudinal direction. Taking a mainspan for 416 m of the cable-stayed bridge as an example, four different damper layout schemes were analyzed by nonlinear dynamic time history method. The results show that installing viscous dampers at the abutment location to function better comparing with other three cases. For getting the best damping effect, the optimal parameters of damper are analyzed. The investigation indicates that adding viscous dampers can significantly reduce the girder movements, and the reduction depends on damper parameters. Finally, the optimal damping parameters with ξ=0.3 and C=10000 can be chosen for this cable-stayed bridge.

scholarly journals Dynamic Response Evaluation of Long-Span Reinforced Arch Bridges Subjected to Near- and Far-Field Ground Motions

2018 ◽  
Vol 8 (8) ◽  
pp. 1243 ◽  
Author(s):  
Iman Mohseni ◽  
Hamidreza Lashkariani ◽  
Junsuk Kang ◽  
Thomas Kang
Keyword(s):  
Ground Motion ◽  
Dynamic Performance ◽  
Time History ◽  
Bending Moment ◽  
Element Model ◽  
Structural Performance ◽  
Far Field ◽  
Inelastic Behavior ◽  
Earthquake Loads ◽  
Arch Bridges

This study assessed the structural performance of reinforced concrete (RC) arch bridges under strong ground motion. A detailed three-dimensional finite element model of a 400 m RC arch bridge with composite superstructure and double RC piers was developed and its behavior when subjected to strong earthquakes examined. Two sets of ground motion records were applied to simulate pulse-type near- and far-field motions. The inelastic behavior of the concrete elements was then evaluated via a seismic time history analysis. The concept of Demand to Capacity Ratios (DCR) was utilized to produce an initial estimate of the dynamic performance of the structure, emphasizing the importance of capacity distribution of force and bending moment within the RC arch and the springings and piers of the bridge. The results showed that the earthquake loads, broadly categorized as near- and far-field earthquake loads, changed a number of the bridge’s characteristics and hence its structural performance.

Dynamic Characteristics of a Long-Span Cable-Stayed Bridge

2011 ◽  
Vol 480-481 ◽  
pp. 1496-1501
Author(s):  
Liu Hui
Keyword(s):  
Finite Element ◽  
Dynamic Characteristics ◽  
Iteration Method ◽  
Natural Frequencies ◽  
Element Model ◽  
Vibration Modes ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Subspace Iteration ◽  
Floating System

In order to study the dynamic characteristics of a super-long-span cable-stayed bridge which is semi-floating system, the spatial finite element model of this cable-stayed bridge was established in ANSYS based on the finite element theory.Modal solution was conducted using subspace iteration method, and natural frequencies and vibration modes were obtained.The dynamic characteristics of this super-long-span cable-stayed bridge were then analyzed.Results showed that the super-long-span cable-stayed bridge of semi-floating system has long basic cycle, low natural frequencies, dense modes and intercoupling vibration modes.

scholarly journals Layout Optimization of Rail Expansion Joint on Long-Span Cable-Stayed Bridge for High-Speed Railway

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Xiaopei Cai ◽  
Wanli Liu ◽  
Kaize Xie ◽  
Wenjun Zhu ◽  
Xiyuan Tan ◽  
...  
Keyword(s):  
High Speed ◽  
Field Tests ◽  
Element Model ◽  
Longitudinal Force ◽  
Main Beam ◽  
Expansion Joint ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Small Resistance ◽  
Set Up

Continuous welded rail (CWR) has been widely applied to the Chinese high-speed railways. It is interesting to reduce the effect of rail longitudinal force on the long-span cable-stayed bridges. Taking the pile-soil interaction into account, the finite element model of CWR on the long-span cable-stayed bridge is established based on the bridge-track interaction theory. The rail longitudinal force can be reduced and the track stability can be improved significantly by installing Rail Expansion Joint (REJ). The layout scheme of REJ plays a controlling role on designing CWR on bridges. Results show that the unidirectional REJ should be laid on both ends of the long-span cable-stayed bridge. Switch rails of REJ are set up on the main beam, stock rails are laid on the simply supported beams and crossing over beam joints, and several-meter long small resistance fasteners need to be laid on the sides of stock rails to reduce the fixed pier longitudinal force near the main beam. The range of REJ laid on cable-stayed bridge is mainly determined by temperature, rail breaking, and seismic condition; the bending and braking loads have little influence on it. Multiple field tests are carried out to prove the validity of the numerical model and the design methodology.

Sign in / Sign up

Export Citation Format

Share Document