A similarity-based damage estimating method of offshore structures

摘要

The present invention discloses a method of estimating the damage to an offshore structure based on similarity, capable of exactly estimating a time point where the damage to a target structure is caused. The method includes the steps of: (a) calculating a variation rate of a natural frequency according to the change in a stiffness for each element of a target structure; (b) acquiring acceleration data by an acceleration sensor attached to the target structure; (c) estimating the natural frequency for each inspection cycle through a modal analysis during operation from the acquired acceleration data; (d) estimating a damage state of the target structure and a damage occurrence time of the target structure by analyzing a variation amount of the estimated natural frequency and determining a danger signal; (e) estimating a damage position of the target structure using a matrix of the variation amount of the natural frequency and the variation rate of the natural frequency; and (f) estimating a damage degree of the target structure caused at an estimated damage location.