Fretting fatigue tests and microstructure analysis of bridge stay cable wires

Abstract

Saddle systems are a popular method for supporting the cables at the pylons of cable-stayed bridges. Fretting fatigue failure of bridge stay cables is a major design consideration for saddle systems. Current design provisions require large-scale tests of these anchoring systems. However, such tests are costly and time-consuming. With this in mind, the current paper presents a small-scale fretting fatigue setup to evaluate the fretting fatigue behavior of bridge stay cable wires at saddle supports. In this paper, fretting tests are conducted on bare and galvanized wires. Hourglass samples are then used to evaluate the material properties and plain fatigue performance of the studied wires. Finally, the microstructure of the wires is evaluated, and the influence of defects on the fretting fatigue life of the wires is discussed.