Assessing time-dependent damage to a cable-stayed bridge through multi-directional ground motions based on material strain measures

2021 ◽  
Vol 227 ◽  
pp. 111417
Author(s):  
Xiaozhen Li ◽  
Peiyao Fu ◽  
Lueqin Xu ◽  
Lifeng Xin
2018 ◽  
Vol 12 (05) ◽  
pp. 1850011 ◽  
Author(s):  
Jiang Yi ◽  
Jianzhong Li ◽  
Zhongguo Guan

To investigate the effectiveness of viscous damper on seismic control of single-tower cable-stayed bridges subjected to near-field ground motions, a 1/20-scale full cable-stayed bridge model was designed, constructed and tested on shake tables. A typical far-field ground motion and a near-field one were used to excite the bridge model from low to high intensity. The seismic responses of the bridge model with and without viscous dampers were analyzed and compared. Both numerical and test results revealed that viscous dampers are quite effective in controlling deck displacement of cable-stayed bridges subjected to near-field ground motions. However, due to near-field effects, viscous damper dissipated most energy through one large hysteresis loop, extensively increasing the deformation and damping force demand of the damper. Further study based on numerical analysis reveals that to optimize deck displacement of cable-stayed bridges during an earthquake, a viscous damper with relatively larger damping coefficient should be introduced under near-field ground motions than far-field ones.


2018 ◽  
Vol 15 (1) ◽  
pp. 1-14
Author(s):  
Ahad Javanmardi ◽  
Zainab Ibrahim ◽  
Khaled Gheadi ◽  
Mohammed Jameel ◽  
Usman Hanif ◽  
...  

Nowadays, development of cable-stayed bridges is increasing around the world. The mitigation of seismic forces to these bridges are obligatory to prevent damages or failure of its structural members. Herein, this paper aimed to determine the near-fault ground motion effect on an existing cablestayed bridge equipped with lead-rubber bearing. In this context, Shipshaw cable-stayed bridge is selected as the case study. The selected bridge has a span of 183.2 m composite deck and 43 m height of steel tower. 2D finite element models of the non-isolated and base isolated bridges are modelled by using SAP2000. Three different near-fault ground motions which are Tabas 1978, Cape Mendocino 1992 and Kobe 1995 were subjected to the 2D FEM models in order to determine the seismic behaviour of the bridge. The near-fault ground motions were applied to the bridge in the longitudinal direction. Nonlinear dynamic analysis was performed to determine the dynamic responses of the bridge. Comparison of dynamic response of nonisolated and base isolated bridge under three different near-fault ground motions were conducted. The results obtained from numerical analyses of the bridge showed that the isolation system lengthened the period of bridge and minimised deck displacement, base shear and base moment of the bridge. It is concluded that the isolation system significantly reduced the destructive effects of near-fault ground motions on the bridge.


2008 ◽  
Vol 08 (04) ◽  
pp. 627-643 ◽  
Author(s):  
G. T. MICHALTSOS ◽  
I. G. RAFTOYIANNIS ◽  
T. G. KONSTANTAKOPOULOS

This paper deals with the stability of the pylons of a cable-stayed bridge under the action of time-dependent loads, due to the vibration of the bridge deck. The stability of such problems of cable-stayed bridges is solved by a technique developed in the Laboratory of Metal Structures and Steel Bridges, of National Technical University of Athens (NTUA), as well as Bolotin's technique for the solution of nonlinear problems of dynamic stability. Three cases are studied: pylons with damping, pylons under forced vibration, and pylons subjected to an arbitrary external dynamic load. Useful relations are established by the aforementioned solution method, examples for a variety of pylons are presented, and interesting results regarding the stability of each case are given in diagrams.


2012 ◽  
Vol 246-247 ◽  
pp. 131-135
Author(s):  
Bao Fu Wang ◽  
Zhong Ren Feng ◽  
Xiong Jiang Wang ◽  
Bai Ben Chen

In this paper, non-uniform dynamic analysis of a cable-stayed bridge is carried out using the large mass method. The Ed Yangtze River highway bridge, constructed in Hubei province, is chosen as a numerical example. In the non-uniform dynamic analysis, various wave velocities are used for the travelling ground motion. Displacements and internal forces solutions obtained for the spatially varying ground motions are compared with those of the uniform excitation. It is observed that the velocity of the ground motion greatly influences the response of the bridge and the variability of the ground motions should be included in the time-history analysis of cable-stayed bridges.


2014 ◽  
Vol 875-877 ◽  
pp. 998-1002
Author(s):  
Wei Bing Luo ◽  
Ji Ming Fan ◽  
Ji Lv ◽  
Li Ya Zhang ◽  
Cui Cui Wu

The seismic responses under the action of far-fault and near-fault ground motions of the bridge tower structure of the long-span cable-stayed bridge are numerically discussed by means of the model of the bottom consolidation of the column. The results show that the responses of tower of the cable-stayed bridge correlate well with the properties of the ground motions. The seismic responses of the model have much larger values under the near-fault velocity pulse-like ground motions than those of the counterpart. The frequency of system reduces as the flexibility of structure decreases because of the rigid foundation; The displace response of tower shows that the rigid foundation has little influence on the seismic response of the cable-stayed bridge, while the acceleration response of the tower implies that rigid foundation has adverse effect. Thus, consideration of the soil-pile-superstructure interaction can be meaningful both in theory and reality during the seismic design of long-span cable-stayed bridge structure.


2011 ◽  
Vol 250-253 ◽  
pp. 3397-3400
Author(s):  
Yong Bin Ma ◽  
Yong Feng Du

A spectrum analysis is one in which the results of a modal analysis are used with a known spectrum to calculate displacements and stresses in the model. It is mainly used in place of a time-history analysis to determine the response of structures to random or time-dependent loading conditions such as earthquakes, wind loads, ocean wave loads, jet engine thrust, rocket motor vibrations, and so on. The paper is to analysis displacements and stresses of a cable-stayed bridge that is used with a known earthquake spectrum.


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