Analysis on Fatigue Load Effects of Bridge Cables Based on Traffic Load Simulation

Cold drawn high-strength wire (first in use the last century) is an important kind of high-strength building steel. The wire, 3~5 times stronger than the widely used low alloy structural steel, is used in China as a major element in bridge cables and prestressed structures. However, the wires are subject to fracture. As the fracture may cause serious consequences, it is necessary to have in-depth study of the cause of wire fracture. This paper tries to study the wire fracture from the perspective of fatigue load. First, data of various types of cable bridge are collected for the construction of a finite element model of typical cable bridge in order to calculate the influence line of cable element. Real traffic load is then investigated to obtain stress history and fatigue stress spectrum for the cable wire. Finally, impact of fatigue load is determined.