考虑累积塑性的船舶裂纹板剩余极限强度  

Residual Ultimate Strength of Hull Cracked Plates Based on Accumulative Plasticity

作　　者：张春涛 王靖[1] 邓军林 ZHANG Chuntao;WANG Jing;DENG Junlin(Fishery Machinery and Instrument Research Institute of Chinese Academy of Fishery Sciences,Shanghai 200092,China;Department of Naval Architecture and Ocean Engineering,Beibu Gulf University,Guangxi Qinzhou 535011,China)

机构地区：[1]中国水产科学研究院渔业机械仪器研究所,上海200092 [2]北部湾大学船舶与海洋工程,广西钦州535011

出　　处：《船舶工程》2020年第9期86-92,共7页Ship Engineering

基　　金：广西自然科学基金重点项目(No.2019GXNSFDA245035);北部湾大学高级别培育项目(No.2016PY-GJ08)。

摘　　要：研究表明在恶劣海洋环境中船体结构整体断裂破坏往往是低周疲劳破坏和累积塑性破坏的耦合结果。为考虑这两者耦合作用的影响,更为真实评估船体结构的极限承载力,文章基于累积塑性和低周疲劳裂纹扩展损伤准则,从理论上分析平面内低周疲劳载荷下裂纹板的残余极限强度,经过一系列数值模拟,首先讨论低周疲劳载荷对裂纹扩展行为的影响,然后随着疲劳裂纹扩展的发展,主要讨论初始变形、焊接残余应力、裂纹扩展长度对承受低周疲劳载荷的船体裂纹板极限强度的影响。研究表明,数值模拟与试验结果较为吻合,极限承载力随着轴向压缩载荷循环次数的增加而降低,且裂纹板由于塑性应变累积,承载能力下降更为显著。The study shows that the overall fracture failure of hull structures is often the coupling result of low-cycle fatigue failure and progressive plastic failure in harsh ocean environment.To consider the coupling effect and make evaluation results on the ultimate bearing capacity of hull structure more practical,the residual ultimate strength of cracked plates subjected to the in-plane low-cycle fatigue loading will be analyzed theoretically on the basis of the accumulative incremental plastic deformation and the low-cycle fatigue crack propagation.After a series of numerical simulations,the effect of low-cycle fatigue crack propagation behavior is discussed firstly,and then with the fatigue crack propagation moving forward,the effect of the initial deformation,the welding residual stress,the crack propagation length on the residual ultimate strength of cracked plates subjected to the low-cycle fatigue load are mainly discussed.The research shows that the ultimate bearing capacity decreases with the increase of axial compression load cycles,and the reduction of the bearing capacity of the cracked plate is more significant due to plastic strain accumulation.

关 键 词：累积塑性 裂纹板 低周疲劳压缩载荷 剩余极限强度 

分 类 号：U661.43[交通运输工程—船舶及航道工程]