Estimating Modal Parameters from Free Vibration Response of Jacket-type Platforms

摘要

Accurate estimate of the modal frequencies and damping ratios of arnstructure is crucial to many practical engineering problems, includingrndamage detection, structural health monitoring, etc. This article introducesrnthe Prony’s method for identifying multiple modal frequencies andrndamping ratios from a measured response time series associated with arnfree vibration motion. Based on data synthesized from a sophisticatedrnfinite element model for a realistic offshore jacket-type platform, werndemonstrate that the modal parameters estimated from the proposedrnmethod agree well with those computed from the finite element modelrndirectly.