scholarly journals Preliminary numerical study on seismic response of ordinary long-span suspension bridges crossing active faults

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Hongyu Jia ◽  
Kang Jia ◽  
Caizhi Sun ◽  
Yanqiang Li ◽  
Chao Zhang ◽  
...  
Keyword(s):  
Finite Element ◽  
Fault Plane ◽  
Numerical Study ◽  
Ground Motions ◽  
Active Faults ◽  
Suspension Bridge ◽  
Element Model ◽  
Suspension Bridges ◽  
Finite Element Software ◽  
Long Span

AbstractThe objective of this paper is to expediently expose the seismic performance pertinent to demand and capacity of general long-span suspension bridges crossing active faults. Firstly three dimensional finite element model of the ordinary long-span suspension bridge is established based on the powerful and attractive finite element software ANSYS. Secondly a series of appropriate fault ground motions with different target final permanent displacements (Tectonic displacements or ground offset) in the direction perpendicular to the fault plane are assumed and applied to the employed long-span suspension bridge. And then the Newmark method is utilized to solve the equation of motion of the long-span suspension bridge structure subjected to fault ground motions in the elastic range. Finally some important conclusions are drawn that the final permanent displacements in the direction perpendicular to the fault plane has significant influence on the seismic responses and demands of general long-span suspension bridges crossing active faults. And the resultant conclusions deliver explicitly and directly specifications and guidelines for seismic design of ordinary long-span suspension bridges across fault-rupture zones.

Nonlinear Stability Analysis of Long-Span Suspension Bridge Cable Tower

2014 ◽  
Vol 1030-1032 ◽  
pp. 802-806
Author(s):  
Xu Luo ◽  
Xin Sha Fu ◽  
Li Xiong Gu ◽  
Lu Rong Cai
Keyword(s):  
Finite Element ◽  
Nonlinear Stability ◽  
Geometrical Nonlinearity ◽  
Suspension Bridge ◽  
Suspension Bridges ◽  
Design Calculation ◽  
Safety Control ◽  
Finite Element Software ◽  
Long Span ◽  
The Stability

The cable tower is the bearing component of long-span suspension bridges, and its structure is very high and bear large force, which determines the stability and is the key of safety control. As for the height of the main tower of a long-span suspension bridge up to 195.3 m, the finite element software ANSYS is used to establish a three-dimensional finite element model (FEM), and the effects of geometric nonlinearity and material nonlinearity on the stability of the main tower are analyzed. The calculation results show that geometrical nonlinearity and material defects have significant influence on the main tower stability, and the nonlinear stability should be considered under wind load in the design calculation.

scholarly journals Probabilistic Assessment of the Safety of Main Cables for Long-Span Suspension Bridges considering Corrosion Effects

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Hao Tian ◽  
Jiji Wang ◽  
Sugong Cao ◽  
Yuanli Chen ◽  
Luwei Li
Keyword(s):  
Probability Model ◽  
Steel Wire ◽  
Suspension Bridge ◽  
Element Model ◽  
Traffic Load ◽  
Suspension Bridges ◽  
Accelerated Corrosion ◽  
Long Span ◽  
Accelerated Corrosion Tests ◽  
Main Cables

This paper presents a reliability analysis to assess the safety of corroded main cables of a long-span suspension bridge. A multiscale probability model was established for the resistance of the main cables considering the length effect and the Daniels effect. Corrosion effects were considered in the wire scale by relating the test results from accelerated corrosion tests to the corrosion stages and in the cable scale by adopting a corrosion stage distribution of the main cable section in NCHRP Report 534. The load effects of temperature, wind load, and traffic load were obtained by solving a finite element model with inputs from in-service monitoring data. The so-obtained reliability index of the main cables reduces significantly after operation for over 50 years and falls below the design target value due to corrosion effects on the mechanical properties of the steel wire. Multiple measures should be taken to delay the corrosion effects and ensure the safety of the main cables in the design service life.

Numerical Simulation of Ultimate of Slings for Three-Tower and Four-Span Suspension Bridge under Tanker Fire

2013 ◽  
Vol 361-363 ◽  
pp. 1187-1193
Author(s):  
Mu Yu Liu ◽  
Wei Tian ◽  
Ying Wang ◽  
Wu Jing
Keyword(s):  
Finite Element ◽  
Failure Time ◽  
Three Dimensional ◽  
Fire Risk ◽  
Suspension Bridge ◽  
Element Model ◽  
Prevention Measures ◽  
Heating Curve ◽  
Finite Element Software ◽  
Three Dimensional Finite Element

Three-dimensional finite element model of Yingwuzhou Yangtze river bridge was established by using the finite element software ANSYS. Since the characteristics of bridge fire differed much from that of buildings, Heating curve HCincwas selected as heating curve caused by tanker fire. Heat loading was imposed on the middle of main span where the tanker fire had taken place of three-tower and four-span suspension bridge . The temperature field and stress, modulus of elasticity, strength of sling changing with time caused by tanker burning in midspan were systematically investigated to obtain the failure time of the sling. The calculation also compared the above results of HCinccurve with that of ISO834 curve. This research can provide some references to fire risk prevention measures of bridge during its service life.

scholarly journals Wind-driven damage localization on a suspension bridge

2016 ◽  
Vol 11 (1) ◽  
pp. 11-21 ◽  
Author(s):  
Marco Domaneschi ◽  
Maria Pina Limongelli ◽  
Luca Martinelli
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Damage Identification ◽  
Structural Response ◽  
Suspension Bridge ◽  
Element Model ◽  
Damage Localization ◽  
Damage Scenarios ◽  
Long Span Bridges ◽  
Long Span

The paper focuses on extending a recently proposed damage localization method, previously devised for structures subjected to a known input, to ambient vibrations induced by an unknown wind excitation. Wind induced vibrations in long-span bridges can be recorded without closing the infrastructure to traffic, providing useful data for health monitoring purposes. One major problem in damage identification of large civil structures is the scarce data recorded on damaged real structures. A detailed finite element model, able to correctly and reliably reproduce the real structure behavior under ambient excitation can be an invaluable tool, enabling the simulation of several different damage scenarios to test the performance of any monitoring system. In this work a calibrated finite element model of an existing long-span suspension bridge is used to simulate the structural response to wind actions. Several damage scenarios are simulated with different location and severity of damage to check the sensitivity of the adopted identification method. The sensitivity to the length and noise disturbances of recorded data are also investigated.

The Influence of the Cable Parameters on Vibration Characteristics of a Long-Span Suspension Bridge

2013 ◽  
Vol 694-697 ◽  
pp. 476-480
Author(s):  
Hai Qing Zhu ◽  
Xie Dong Zhang
Keyword(s):  
Dynamic Characteristics ◽  
Optimization Design ◽  
Suspension Bridge ◽  
Element Model ◽  
Suspension Bridges ◽  
Cable System ◽  
Long Span ◽  
Long Span Bridge ◽  
The World ◽  
Set Up

The type of suspension bridge is used all over the world because of its long span. But the cable system which forced the main load is vulnerable to damage and corrosion. In order to discuss the dynamic characteristics of typical long-span suspension bridges, a finite-element model of a typical long-span bridge was set up with ANSYS, and its top ten frequencies and vibration types were calculated. What’s more the dynamic characteristics under the variations such as modulus of elasticity, sectional size of the cable system, initial strain of the cable, as well as the deficiency of suspender cable were discussed. According to the analysis, the researchers got the conclusion that how the cable system impacts the whole bridge and which suspender cable plays the most significant role. Moreover, the results could serve as some valuable references for the optimization design and preservation of long-span suspension bridges.

Mechanics Characteristics Study for Cable-Stayed-Suspension Bridges

2011 ◽  
Vol 243-249 ◽  
pp. 1817-1825
Author(s):  
Jing Qiu ◽  
Rui Li Shen ◽  
Huai Guang Li
Keyword(s):  
Finite Element ◽  
Suspension Bridge ◽  
Simulation Method ◽  
Suspension Bridges ◽  
Preliminary Design ◽  
Structural System ◽  
Long Span Bridges ◽  
Long Span ◽  
Element Simulation ◽  
Mechanics Characteristics

As a composite structure, the cable-stayed-suspension bridge is characterized by relatively new structure, great overall stiffness and long-span capacity, which has been proposed for the design of some extra long-span bridges. In order to research further into the mechanics characteristics of this type of structural system, the proposed preliminary design of a cable-stayed-suspension bridge with a main span of 1800m is analyzed by means of finite element simulation method. The advantages on overall stiffness in the cable-stayed-suspension bridge are summarized in comparison with the three-span suspension bridge and the single-span suspension bridge. Then, the reasons for the fatigue of the longest suspension cables in the cable-stayed-suspension bridge are also discussed in this paper.

Influence of Central Buckle on Dynamic Behavior of Long-Span Suspension Bridge with Deck-Truss Composite Stiffening Girder

2013 ◽  
Vol 838-841 ◽  
pp. 1096-1101 ◽  
Author(s):  
Feng Jiang Qin ◽  
Jin Di ◽  
Jie Dai ◽  
Guang Ling Li
Keyword(s):  
Finite Element ◽  
Large Scale ◽  
Great Influence ◽  
Suspension Bridge ◽  
Element Model ◽  
Vibration Modes ◽  
Element Analysis ◽  
Long Span ◽  
Main Cable ◽  
Central Buckle

A 3-D finite element model for Yueyang Dongting Lake bridge was established with a large scale general finite element analysis software, and the subspace iteration method was adopted to analyze the natural vibration characteristics of the bridge, meanwhile, the influences of settings different types of central buckles at the mid-span of the main spans between the main cables and girder on the dynamic behaviors of the long-span suspension bridge with deck-truss composite stiffening girder were studied. The results show that compared with only setting short hanger cable at mid-span, the the whole rigidity of suspension bridge is raised and the natural frequencies increase by the setting central buckle, but various types of vibration modes are affected in different extents; among all of these vibration modes, the antisymmetric vibration and Longitudinal floating of stiffening girder are most obviously affected. The stiffness of central buckle has a great influence on the vibration of main cable, while compared with only setting short hanger cable, the vibration of main cable increases 7.32% while setting the rigid central buckle. The conclusions of this paper provide theoretical basis for the using of central buckle in long-span suspension bridge.

Sign in / Sign up

Export Citation Format

Share Document