Why can the GB150 stress analysis method not be used for fatigue-resistant vessels?
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Why can the GB150 stress analysis method not be used for fatigue-resistant vessels? I would appreciate some advice from fellow sailors.
Since the relationship curve between alternating stress amplitude and number of cycles is not applied, it is unknown how many cycles can be performed. . . Personal opinion
This post was last edited by zhangjuhua on 2015-9-6 at 21:28. The tables used in it take static loads into consideration, and the calculations are based on conventional allowable stresses; therefore, the values remain constant at the same temperature. In contrast, fatigue-resistant containers are subjected to dynamic loads, and their equivalent or equivalent allowable stresses vary depending on specific conditions – they may not be the same even at the same temperature, as they are influenced by factors such as the number of cycles, stress amplitude, and mode of loading. This is why it’s difficult to obtain results for fatigue analysis simply by referring to tables, as there are many more influencing factors compared to the case of static loads
Fatigue analysis is based on stress analysis; the stress analysis phase identifies the high-stress areas required for fatigue analysis, after which fatigue analysis is conducted to determine whether the material can withstand the corresponding number of cycles. Stress analysis is the first step in fatigue analysis; only after that is a cyclic load applied to determine whether the container is safe.
When the expected total number of cycles N is >= 1000, fatigue analysis design must be carried out, along with stress analysis design, regardless of whether peak stresses are present or not. N