The Study of Storm Loading Simulation Model for Fatigue Strength Assessment of Ship Structural Members

摘要

Tomita (1992) proposed a storm loading simulation model for a ship hull structural fatigue strength assessment. They analyzed encountered wave data collected from large number of ships and introduced the random loading model. The model simulates the encountered wave state history of an ocean going ship. But, the statistical character of wave data is not consistency with a wave frequency table to calculate a long-term distribution of wave-induced load, such as Hobgen's wave frequency table. The purpose of this study is to introduce a new storm loading simulation model which is consistent with a long-term wave frequency table. Applying the storm loading model to calculate a ship structural response in the ocean, both the long-term distribution of the wave -induced response for extreme load and the time history of response for fatigue assessment of structure can be obtained directly. We demonstrate a fatigue strength analysis employing a crack propagation low.