Improvement of Prediction Accuracy of Hull Fatigue Life using a Fatigue Damage Sensor

Abstract

SummaryThe characteristics of Fatigue Damage Sensors (FDS) that are in use for fatigue life estimation of monitoring structural members in ship structures are discussed in order to improve prediction accuracy of estimated fatigue life exposed to random wave loads such as storms under various loading conditions peculiar to ship structures. Coefficients affected by loading histories against constant amplitude loading and mean stress levels are introduced for the estimation procedure using FDSs and confirmed by a series of fatigue testing and numerical simulations. This newly proposed fatigue life estimation procedure using obtained coefficients is checked by comparison results of fatigue test for large size structural model on which FDSs and strain gauges are provided simultaneously and to which random loads by assumption of storm patterns are applied under various mean stress levels.