船舶力学
船舶力學
선박역학
JOURNAL OF SHIP MECHANICS
2015年
5期
541-552
,共12页
张鼎%黄小平%崔维成
張鼎%黃小平%崔維成
장정%황소평%최유성
风暴模型%波浪诱导应力%单一曲线模型%焊接残余应力%表面裂纹%疲劳裂纹扩展预报
風暴模型%波浪誘導應力%單一麯線模型%銲接殘餘應力%錶麵裂紋%疲勞裂紋擴展預報
풍폭모형%파랑유도응력%단일곡선모형%한접잔여응력%표면렬문%피로렬문확전예보
storm model%wave-induced stress%unique curve model%residual stress%surface crack%fatigue crack growth predication
风暴模型是Tomita等提出的用来评估船舶结构疲劳强度的一种随机波浪载荷简化模型,它能表达波浪载荷是与时间相关的随机过程。文中介绍了风暴模型及波浪诱导应力短期分布的基本特征。将风暴模型和裂纹扩展率单一曲线模型及焊趾表面裂纹应力强度因子的计算方法结合起来,探讨了复杂载荷作用下船舶结构疲劳裂纹扩展预报方法。并用权函数法计算了给定残余应力分布的表面裂纹应力强度因子。预报了对接焊接接头焊趾处表面裂纹在风暴波浪载荷作用下的疲劳裂纹扩展行为,结果表明风暴的大小、顺序,初始裂纹尺寸及残余应力对裂纹扩展行为影响明显。合理的风暴模型参数及初始裂纹尺寸的确定对船舶结构的疲劳寿命预报是非常重要的。
風暴模型是Tomita等提齣的用來評估船舶結構疲勞彊度的一種隨機波浪載荷簡化模型,它能錶達波浪載荷是與時間相關的隨機過程。文中介紹瞭風暴模型及波浪誘導應力短期分佈的基本特徵。將風暴模型和裂紋擴展率單一麯線模型及銲趾錶麵裂紋應力彊度因子的計算方法結閤起來,探討瞭複雜載荷作用下船舶結構疲勞裂紋擴展預報方法。併用權函數法計算瞭給定殘餘應力分佈的錶麵裂紋應力彊度因子。預報瞭對接銲接接頭銲趾處錶麵裂紋在風暴波浪載荷作用下的疲勞裂紋擴展行為,結果錶明風暴的大小、順序,初始裂紋呎吋及殘餘應力對裂紋擴展行為影響明顯。閤理的風暴模型參數及初始裂紋呎吋的確定對船舶結構的疲勞壽命預報是非常重要的。
풍폭모형시Tomita등제출적용래평고선박결구피로강도적일충수궤파랑재하간화모형,타능표체파랑재하시여시간상관적수궤과정。문중개소료풍폭모형급파랑유도응력단기분포적기본특정。장풍폭모형화렬문확전솔단일곡선모형급한지표면렬문응력강도인자적계산방법결합기래,탐토료복잡재하작용하선박결구피로렬문확전예보방법。병용권함수법계산료급정잔여응력분포적표면렬문응력강도인자。예보료대접한접접두한지처표면렬문재풍폭파랑재하작용하적피로렬문확전행위,결과표명풍폭적대소、순서,초시렬문척촌급잔여응력대렬문확전행위영향명현。합리적풍폭모형삼수급초시렬문척촌적학정대선박결구적피로수명예보시비상중요적。
Storm model proposed by Tomita and coworkers is a simplified random loading model for fatigue strength assessment of ship structures. The time dependent random wave loading can be expressed by the storm model. The basic characteristics of storm model and short-term distribution situation of wave-induced stress are described. Storm model is combined with a unique crack growth rate curve and SIF calculation e-quations for surface crack in the weld toe, and the procedure to predict the fatigue crack growth behavior of ship structures under complex loading conditions is discussed. Weight function is used to calculate SIF of surface crack under given residual stress distribution. Fatigue crack growth behavior of surface crack at weld toe of butt welded joint in ship hull under storm wave loading condition is predicted. The results show that the size and order of storms, the initial size of crack and residual stress have significant effect oncrack growth behavior. Reasonable storm model parameters and initial crack size are very important for fa-tigue life prediction of ship structures.