中国舰船研究2016，Vol.11Issue(2)：51-57,7.DOI:10.3969/j.issn.1673-3185.2016.02.008
厚钢板疲劳裂纹扩展前缘应力状态试验与数值仿真
Investigation on the stress state along the crack front in the fatigue crack growth rate test for thick high strength steel plates
摘要
Abstract
Complex environmental loads would unavoidably lead to the fatigue damage in marine struc⁃tures, and the case worsens in high strength steel thick-welded structures which have typical tri-axial stress and the feature of brittleness. To study the stress state along the crack front, a standard fatigue crack growth rate test for high strength steel Q370QE with a thickness of 36 mm is conducted, and the correspond⁃ing material parameters and the threshold of stress intensity factor are obtained. Next, the abnormal behav⁃ior of a crack front during crack growth and the stress state along crack front during crack growth are ana⁃lyzed with the finite element method. Accordingly, the varying tendency of crack front shape could be quali⁃tatively defined. Finally, local constraint factors are introduced in order to quantitatively describe the stress state along the crack front with the growth of fatigue crack based on plasticity analysis, which provides prop⁃er explanation to why the crack front changes from slant to flat with the crack growing. The calculated stress intensity factor could only describe the stress state in the center area, but distortion is inevitable on the sur⁃face, while the local constraint factor can fully describe the stress state along the crack tip zone.关键词
疲劳裂纹扩展速率试验/有限元分析/裂纹前缘应力状态/应力强度因子/局部约束因子Key words
fatigue crack growth rate test/finite element analysis/stress state along the crack front/stress intensity factor/local constraint factor分类
交通工程引用本文复制引用
党之凡,乐京霞,董岩..厚钢板疲劳裂纹扩展前缘应力状态试验与数值仿真[J].中国舰船研究,2016,11(2):51-57,7.基金项目
国家自然科学基金资助项目（51009111）；中央高校基本科研业务费专项资金资助项目 （）
