摘要
以材料属性和载荷为随机变量,以控制分叉裂纹扩展的修正Paris-Erdogan公式为基础,结合建立在随机有限元法基础上的四阶矩可靠性分析方法,提出了基本变量服从任意分布时,二维分叉裂纹扩展寿命可靠度的计算方法,裂纹扩展方向采用最大周向应力准则。以平面二维分叉裂纹为例分析了其扩展寿命及可靠度变化规律,结果表明,随着裂纹的扩展,平板剩余寿命逐渐缩短,剩余寿命对设计寿命的可靠度随着裂纹扩展而逐渐降低。
Stochastic finite element method,fourth moment reliability method were employed to present a reliability-based method for crack growth life of structures with non-normal random variables in which material properties and applied loadings were considered as random parameters.Taking reliability-based analysis for crack growth life of a plate with a bifurcated crack and subjected to constant distributed stress at updown edges of the plate as a numerical example in which Paris-Endogan formula were used and the direction of the crack propagation followed the maximum circumferential stress criterion.The numerical results show that the fatigue life of the plate with moment method;reliabilitybifurcated crack are longer than that of the plate without bifurcated crack for the same crack growthsize,and the life reliability of the plate is descendent as the crack grows.
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2010年第22期2722-2725,共4页
China Mechanical Engineering
基金
国家高技术研究发展计划(863计划)资助项目(2007AA04Z442)
国家自然科学基金资助重点项目(50875039)
"十一五"国家科技支撑计划资助项目(2009BAG12A02)
沈阳市人才资源开发专项资金资助项目(2007010103001)
沈阳市科学技术计划科技攻关项目(1071057-9-00)
关键词
裂纹扩展寿命
分叉裂纹
非正态随机参数
四阶矩法
可靠性
crack propagation life
bifurcated crack
non-normal random parameter
fourth moment method
reliability
