Time-variant reliability analysis of ship grillage structure

Material characteristics, environmental conditions and loading characteristics under the time domain features shall be taken into consideration so as to effectively evaluate the reliability of ship grillage structure. Moreover, the method of time-variant reliability serves as an effective approach to solve the problem. In the paper, based on the loading environmental features of ships during the enlistment, research has been conducted on the changing of material geometrical and mechanical characteristics with time under the corrosive action. Furthermore, on the basis of time-variant theory, the timevariant model of section modulus as well as bending strength concerning the ship grillage structure has been established, thus generating a time-variant reliability analysis method integrated with out-crossing rate and First Order Second Moment(FOSM) method. Besides, the paper analyzes the time consecutiveness of ship grillage structure reliability based on the time-variant reliability cases of certain ship grillage structure under the corrosion environment while the failure probability of the ship during the enlistment has been accurately predicted.