摘要
船舶与海洋工程结构中由于材料本身缺陷或服役过程中产生的细小裂纹,使结构不可避免地产生裂纹损伤,造成应力集中而破坏。为了研究含裂纹缺陷低合金钢构件的裂纹扩展行为,以应用广泛的Q345钢为研究对象,基于近场动力学(Peridynamics,PD)理论提出一种改进的双参数PD方法。首先考虑PD力的非局部长程力特性,推导对应的键刚度系数;其次,根据含裂纹缺陷Q345钢拉伸破坏的线性和非线性的力学行为,构建双参数PD本构力函数的基本形式。通过研究不同双裂纹间距、长度和角度的Q345钢裂纹扩展行为,与试验结果对比验证本文改进的双参数PD方法的准确性,并且给出交变荷载情形下疲劳裂纹扩展的计算方法。结果可为船舶钢构件的优化设计和断裂预防提供参考。
In ship and ocean engineering,structures inevitably encounter crack damage due to material de-fects or microcracks generated during their service time,which causes stress concentration and structural fail-ure.To better simulate the crack propagation behavior of steel members with defects,Q345 steel was taken as the research object in this paper,an improved two-parameter peridynamic(PD)model was proposed based on the PD theory.The internal length effect of long-range forces was considered and the corresponding expres-sions of coefficient were deduced firstly.Furthermore,the basic form of the constitutive force function of the two-parameter PD was constructed based on the linear and nonlinear mechanical behaviors of the failure pro-cess of Q345 steel with defects.The crack propagation behaviors of Q345 steel with different crack distance,length and angle were studied and compared with the experimental results,which verified the accuracy of the present work.Then,the calculation method of fatigue crack propagation under alternating load was given.The research results may provide a reference for the optimization design and failure prevention of steel mem-bers in ocean engineering.
作者
李双
吕海宁
黄小华
杨建民
LI Shuang;LÜHai-ning;HUANG Xiao-hua;YANG Jian-min(State Key Laboratory of Ocean Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Yazhou Bay Institute of Deepsea SCI-TECH,Shanghai Jiao Tong University,Sanya 572000,China;Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education,Guangxi University,Nanning 530004,China)
出处
《船舶力学》
EI
CSCD
北大核心
2024年第1期103-114,共12页
Journal of Ship Mechanics
基金
国家自然科学基金资助项目(51979159)
上海市科委“科技创新行动计划项目”(19DZ1207300)。
