Prediction of Fatigue Strength of Extra-Large Container Ships Based on Spectrum Analysis

With the rapid development of maritime transportation industry, container ships have quickly become the mainstream ship model due to their advantages of fast shipping speed, high handling efficiency, and low operating costs. At the same time, their large-opening structure has resulted in poor performance in bending strength, torsional strength and other mechanical properties. In order to ensure the structural safety performance of extra-large container ships, it is necessary to conduct an in-depth research on its fatigue damage and strength life. Based on the spectrum analysis, this paper takes the model 8601ETP extra-large container ship as an example, and adopts finite element modeling to obtain distribution range of the alternating stress; it also uses SN curve and linear cumulative damage theory to predict the fatigue damage and strength life of the container ship. The research results show that the fatigue damage of the extra-large container ship at full load is significantly more severe than that at no load; the degree of structural damage at the position of the keyhole is greater than that at the position of the hatch corner, so it is the hotspot for the fatigue damage analysis and strength check of extra-large container ships. This study provides certain theoretical reference and data support for improving the safety performance of large container ships, and it also enriches the theory of fatigue strength evaluation.