Caso de Estudo: Análise mecanica e fractográfica de um cabo de a？o pré-esfor？ado

this paper presents results of a failure analysis study to characterize the damage phenomenon that occurred in prestressed steel cables of a suspension bridge. this study includes: material characterization using chemical, microestrutural and hardness analysis; fractographic analysis by scanning electron microscopy (sem); mechanical tests of the material in static tension; fatigue tests (s-n curves). the fatigue tests were carried out in laboratory air only and in the laboratory air also but after previous exposure in tap water to simulate the working environment of the cables. fractured surfaces for more than 50% of the rods were brittle failure type and the remains were ductile failure (cup-and cone type). due to the characteristics of the work environment (close to a river) stress corrosion was also observed.