Tribo-corrosion-fatigue behaviors of the parallel wires of main cable in the suspension bridge

Abstract

The suspension bridge in service is subjected to the coupling effects of dead load, vehicle load, wind load and corrosive environment. These factors cause the tribo-corrosion-fatigue behaviors of parallel steel wires of main cable, which seriously affect the load-bearing safety of the main cable. Therefore, it is of great significance to investigate tribo-corrosion-fatigue behaviors of steel wires and the saddle materials. The self-made test rig was developed to carry out tribo-corrosion-fatigue tests between the parallel steel wires, and between the steel wire and saddle groove. Tribo-corrosion-fatigue behaviors (friction coefficient, wear profile, failure area, wear mechanism and wear coefficient) of main cable wires was revealed by high speed digital microscope and scanning electron microscope. The results show that the friction coefficient shows a trend of rapid increase – decrease – increase – stabilization. It decreases with increasing contact load as compared to an increase with increasing fatigue load. The wear width and depth both increase nearly linearly with increasing cycles, while the failure area increases nearly parabolically. As the contact load and fatigue load increase, the wear width and depth increase, and the corrosion of wear area is more obvious. The wear coefficient decreases first and then increases with the increase of cycles. The wear mechanisms are mainly adhesive wear, abrasive wear, fatigue wear and corrosion wear. The increase of contact load and fatigue load promotes the wear deterioration behaviors of cable wires. The results have fundamental significance to ensure the load-bearing safety of the main cable and improve the service safety of the suspension bridge.