含缺陷船体纵骨节点疲劳裂纹扩展寿命评估  

Three-dimensional Crack Growth Simulation and Life Prediction in Typical Joints of Ship Hull

作　　者：张淞 徐铁柱 甘进[1,3] 吴卫国[1,3] ZHANG Song;XUTiezhu;GAN Jin;WU Weiguo(School of Transportation,Wuhan University of Technology Wuhan 430063,China;Wuhan Second Ship Design Institute,Wuhan 430064,China;Green&Smart River-Sea-Going Ship,Cruise and Yacht Research Center,Wuhan University of Technology,Wuhan 430063,China)

机构地区：[1]武汉理工大学交通学院,武汉430063 [2]武汉第二船舶设计研究所,武汉430064 [3]武汉理工大学绿色智能江海直达船舶与邮轮游艇研究中心,武汉430063

出　　处：《中国造船》2020年第1期29-40,共12页Shipbuilding of China

基　　金：国家自然科学基金面上项目(51879208)。

摘　　要：船舶纵骨节点往往存在焊接缺陷,焊接缺陷将引发裂纹,大大降低构件的疲劳性能。本文基于断裂力学理论,将焊接缺陷等效成半椭圆型表面裂纹,采用FRANC3D和ABAQUS联合仿真的方法,研究带初始裂纹的船舶舭部纵骨与横舱壁连接节点裂纹的扩展寿命评估方法。分析了初始裂纹位置、形状、裂纹面角度对裂纹扩展寿命的影响规律。并根据纵骨节点试验中的初始缺陷的位置,采用此联合仿真方法模拟了裂纹扩展过程。结果表明初始裂纹位置、形状对扩展寿命影响较大,随着初始裂纹向腹板靠近,寿命变短,裂纹扩展寿命随着初始裂纹形状比的增大而增大。初始裂纹角度对疲劳寿命影响不明显,随着角度增大,寿命变长。通过对试验中初始缺陷的等效简化,在裂纹稳定扩展阶段,仿真得到的裂纹扩展寿命与试验结果吻合较好。Welding defects widely exist in ship welding joints and initialize cracks,greatly reducing the fatigue properties of the welded members.Based on the theory of fracture mechanics,the welding defect is regarded as a semi-elliptical surface crack.Then the predicting method of crack propagation life for the juncture of bilge longitudinal and transverse bulkheads with initial cracks is investigated with the finite element program ABAQUS and a 3D fracture analysis software FRANC3D.The influence of the initial crack location,crack shape and crack orientation on the crack growth life is discussed,and then according to the location of initial defects in the fatigue test,the simulation method is used to simulate the crack propagation process.The results show that the effects of initial crack location and crack shape on crack growth life is significantly.The crack propagation life decreases when the initial crack position moves to the web.Fatigue life is increased with the increase of crack shape ratio.The propagation life is insensitive to initial crack orientation.As the angle increases,the life becomes longer.By comparison,the crack growth life of the simulation is in good agreement with the experimental results in the long crack propagation stage.

关 键 词：纵骨穿舱节点 初始缺陷 扩展寿命 断裂力学 数值仿真 疲劳试验 

分 类 号：U661.43[交通运输工程—船舶及航道工程]