Analysis and Experiments on the Secondary Stresses of the Parallel Wire Cable in Suspension Bridge

Suspension-bridge cables are constructed from strands of galvanized steel wire. They are failure-critical structural members, so a fundamental understanding of their mechanics is imminently important in quantifying suspension bridge safety. The load-carrying capabilities of such strands after local wire failures have been the subject of many theoretical studies utilizing analytical equations and finite-element analysis. Little experimental data, however, exists to validate these models.Over the past five years we have developed a methodology for measuring stress/strain transfer within parallel wire strands of suspension bridge cables using neutron diffraction [1,2]. In this paper we describe the design and verification of parallel cable strands used in our studies. We describe the neutron diffraction strain measurements performed on standard 7-wire and expanded 19-wire models in various configurations at both the Los Alamos National Laboratory Spectrometer for Materials Research at Temperature and Stress (LANL SMARTS) and at the Oak Ridge National Laboratory VULCAN Engineering Materials Diffractometer (ORNL VULCAN). Particular attention is placed on the challenges of aligning and measuring multibody systems with high strain gradients at body-to-body contact points.

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Effect of Tensile Load for Detecting Broken Wires of Parallel Wire Cable Based on Guided Waves

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.325-326.848 ◽

2013 ◽

Vol 325-326 ◽

pp. 848-851

Author(s):

Bo Ming Wu ◽

Ji Dong Zhang ◽

Jian Dong Zhang ◽

Cong Ming Zhu ◽

Xin Jun Wu ◽

...

Keyword(s):

Guided Waves ◽

Tensile Load ◽

Condition Assessment ◽

Parallel Wire ◽

Bridge Safety ◽

Parallel Wire Cable

Condition assessment of cables has gained more attention for the bridge safety. The cable is under tensile load in service. The effect of tensile load for detecting broken wires on parallel wire cable based on guided waves is investigated. The sample cable with broken wires under several levels of tensile load is detected using guided waves based on the magnetostrictive effect. The amplitude of flaw echo increases monotonically with the increasing of tension. The results indicate that the tensile load brings benefit for detecting broken wires in the parallel wire cable.

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Damage propagation monitoring and fatigue properties of parallel wire cable

10.1117/12.817479 ◽

2009 ◽

Author(s):

C. Lan ◽

W. Zhou ◽

H. Li

Keyword(s):

Fatigue Properties ◽

Parallel Wire ◽

Damage Propagation ◽

Parallel Wire Cable

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Guidelines for Inspection and Strength Evaluation of Suspension Bridge Parallel Wire Cables

10.17226/23338 ◽

2004 ◽

Cited By ~ 4

Author(s):

◽

Keyword(s):

Suspension Bridge ◽

Strength Evaluation ◽

Parallel Wire

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Fatigue Properties Assessment of Corroded Cable

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.413-414.757 ◽

2009 ◽

Vol 413-414 ◽

pp. 757-764 ◽

Cited By ~ 3

Author(s):

Cheng Ming Lan ◽

Hui Li

Keyword(s):

Monte Carlo ◽

Fatigue Life ◽

Fatigue Test ◽

Fatigue Properties ◽

Test Results ◽

Original Design ◽

Parallel Wire ◽

Parallel Wire Cable ◽

As Stress ◽

Wire Fatigue

Based on fatigue test results of corroded wires obtained from dissection of actual parallel wire cables which were used on a certain domestic cable-stayed bridge, the fatigue properties of corroded parallel wire cable are investigated by the method of Monte Carlo simulation in this paper. The results of fatigue life and corrosion degree of corroded wire are presented. Comparisons between the original design information and fatigue test results, it can be seen that corrosions make the fatigue lives of wires decreasing sharply. The fatigue life of individual wire is described by Weibull distribution considered some useful parameters such as, stress range, mean stress, mean static strength and length effects. The effects of percentage of broken wire, cable S-N curve parameter on cable fatigue life are discussed. It can be seen that the cable fatigue lives are controlled by a small fraction of the cable wires with the shortest fatigue lives. Finally, the S-N curves of cable are calculated by Monte Carlo simulations based on the results of individual wire fatigue test, and compared with the results of cable fatigue test.

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