【摘要】 点腐蚀作为海水浸没带腐蚀的一种主要形式,是现役船舶,特别是老龄船结构的重大安全隐患.为了研究点腐蚀对钢板的抗压极限承载能力的影响,文中对未穿透低碳钢板开展了非线性有限元分析.计算结果表明,单侧点腐蚀引起的偏心对钢板的极限抗压能力有显著影响.点腐蚀越密集(DOP越大),板越薄(β越大),点腐蚀深度改变造成板的极限承载能力差异越大,DOP达到或超过20%时尤其显著.大部分船体板属于典型的柔性板(β为3左右),海水全浸带腐蚀现象严重,点腐蚀密度大,仅采用点腐蚀密集度参数DOP来表征板点腐蚀破坏程度还有所欠缺,薄壁效应需要给予充分考虑.更多还原

【Abstract】 As one of main corrosion type of immersed ship hull,pitting corrosion could bring about heavy damage even accident to in-service ships,particularly old aged ships.To investigate effects of pits on ultimate compressive strength of mild steel plates,a series of non-linear FEM analysis on plates with non-through pits are undertaken in the paper.It is presented that eccentricity induced by one-side pits has considerable effects on ultimate compressive capacity of plates.The more intense the pits are(the larger DOP),or / and the thinner the plate is(the larger β),the difference of ultimate compressive capacity caused by change of pits depth is more serious,especially when DOP reaches or beyond 20%.Moreover,majority of ship applied plates belongs to typical slender plates(β≥3),hence under severe immersed corrosion,it is not enough to occupy DOP exclusively to represent the extent of damage caused by pits,"thin-plate effect" should be given ample consideration.更多还原