邮轮甲板结构冗余度的可靠性研究

Reliability research on redundancy of cruise deck structure

开展船体结构冗余度的可靠性研究,对于保证船体结构在局部损伤(如永久的局部变形、裂纹或焊缝失效)之后不会导致整个加筋板甚至船体梁的破坏具有重要意义。本文拟合了损伤前后扶强材单元承载力比值与扶强材柔度的关系,提出损伤加筋板极限承载力计算的逐步迭代法。以邮轮甲板结构为研究对象,构造邮轮甲板结构冗余度可靠性计算的极限状态方程,基于概率统计的方法,确立邮轮甲板结构的极限强度、波浪弯矩和静水弯矩等随机变量的随机模型和概率特性;采用一次二阶矩法计算一艘极地邮轮甲板结构冗余度的可靠性指标和失效概率,讨论了上层建筑不同参与度对甲板结构冗余度的影响。结果表明,该极地邮轮甲板结构具有足够的冗余度,所提方法对于其它船型的冗余度评估具有借鉴作用。

It is of great significance to carry out the reliability research on the redundancy of hull structures to ensure that the entire stiffened plates or even the hull girders will not be damaged after local damage(such as permanent local deformation,crack or weld failure).In this paper,the relationship between the ratio of the element bearing capacity of stiffeners before and after damage and the flexibility of stiffeners was fitted,and a step-by-step iterative method for calculating the ultimate bearing capacity of damaged stiffened slabs was proposed.With a cruise deck structure taken as the research object,the limit state equation for the reliability calculation of the redundancy of the cruise deck structure was constructed.Model and probabilistic characteristics,the reliability index and failure probability of the deck structure redundancy of a polar cruise ship were calculated by the first-order second moment method,and the influence of different superstructure participation degrees on the deck structure redundancy was discussed.The results show that the deck structure of the polar cruise ship has sufficient redundancy,and the proposed method can be used as a reference for the redundancy evaluation of other ship types.