本文针对船舶在中垂中拱等危险时刻，船体板遭受较大的弯曲塑性时，船体板三维表面裂纹的深度方向裂尖CTOD与船体板的最外层纤维等效塑性应变的关系进行研究。并采用有限元分析方法探讨了在纯弯曲状态下裂纹形状因子、裂纹深度和板厚等不同影响因素对裂尖处CTOD的影响，并基于有限元模拟的数据，提出了船体板表面裂纹在弯曲状态下基于应变关系的CTOD估算公式。
Based on ship under the situation of hogging and sagging, hull plate subjected to large plastic bending, three-dimensional surface crack depth direction crack tip CTOD of hull plate and the relationship between the equivalent plastic strain of the outermost fibers of the hull plate is studied.And using the method of finite element analysis discussed different influence factors on the crack tip of CTOD, such as shape factor of crack, crack depth and thickness under pure bending, and based on the data of finite element simulation, puts forward the strain-based CTOD estimate formula of hull plate surface crack subjected to large plastic bending.
2018,40(6): 35-39 收稿日期：2018-04-20
DOI：10.3404/j.issn.1672-7649.2018.06.008
分类号：U661.42
基金项目：广西自然科学基金面上资助项目（No.2016GXNSFAA380033）；广西中青年教师基础能力提升项目（No.2017KY0809）；钦州学院高级别培育资助项目（No.2016PYGJ08）
作者简介：杜波(1979-),男,硕士,讲师,研究方向为结构安全性与性能
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