An experimental-finite element method based on beach marks to determine fatigue crack growth rate in thick plates with varying stress states
An experimental-finite element method based on beach marks to determine fatigue crack growth rate in thick plates with varying stress states
复制标题
基于滩痕的实验有限元方法确定不同应力状态厚板的疲劳裂纹扩展速率
DOI：
10.1016/j.engfracmech.2018.04.015
复制
发表时间：
2018-06
影响因子：
5.4
通讯作者：
Guedes Soares Carlos
中科院分区：
文献类型：
--
作者：
Yue Jingxia;Dong Yan;Guedes Soares Carlos
疲劳裂纹扩展速率与应力状态之间的关系对于疲劳寿命的估计具有重要意义，特别是对于具有复杂应力状态的厚焊结构。本文提出了一种混合实验-有限元方法，旨在获得相应的平面应力和平面应变状态下的疲劳裂纹扩展速率。提出了一种静态载荷标记方法，在已知循环次数下对单侧缺口弯曲试件的一系列裂纹前缘进行标记，并采用非线性有限元法对其进行分析，通过局部约束因子来评估其应力状态。在考虑非正交网格影响的情况下，采用1/4节点位移法计算厚度中心及平面应变和平面应力状态近似存在并随裂纹扩展保持不变的表面位置的应力强度因子。应用j积分法和虚拟裂纹闭合技术，验证了方法处理实际裂纹体问题的性能。裂纹长度增量根据裂纹前缘轮廓确定。根据国家标准GB/T 6398-2000，测定了平面应变和平面应力状态的Theda/dN-ΔKcurves，并与正常疲劳裂纹扩展速率试验结果进行了比较。利用该曲线对循环拉伸载荷作用下t型板焊接接头焊趾半椭圆表面裂纹的疲劳裂纹扩展行为进行了评价，并将分析结果与实验结果进行了比较。利用混合方法确定的曲线成功地预测了实验中观察到的渐近裂纹形状。
The relation between the fatigue crack growth rate and stress state is significant for fatigue life estimation, especially for thick-welded structures with complex stress states. This paper proposes a hybrid Experimental-Finite Element Method aimed to obtain the fatigue crack growth rate corresponding to plane stress and plane strain states. A static load marking method is proposed to mark a series of crack fronts in a single edge notched bending specimen at known numbers of cycles, which is analysed by nonlinear finite element method to evaluate the stress state by a local constraint factor. Stress intensity factor at the center of the thickness and the surface position where plane strain and plane stress states approximately exist and remain unchanged with crack propagation, is calculated by the 1/4-node displacement method with consideration of non-orthogonal mesh influence. TheJ-integral method and the virtual crack closure technique are also applied to check the performance of the methods in dealing with the actual cracked body problem. Crack length increments are determined based on the crack front profiles. Theda/dN-ΔKcurves of plane strain and plane stress states are determined and compared with the results from normal fatigue crack growth rate tests according to Chinese standard: GB/T 6398-2000. The fatigue crack growth behavior of a semi-elliptical surface crack located at the weld toe of a T-plate welded joint subjected to cyclic tension loading is assessed based on the curves and the analytical results are compared with the experimental results. The asymptotic crack shape observed in experiments is successfully predicted by using the curves determined by the hybrid method.
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DOI：
10.1111/j.1460-2695.1992.tb01307.x
发表时间：
1992-07
影响因子：
3.7
作者：
G. Wang;B. Palmberg;A. Blom
通讯作者：
G. Wang;B. Palmberg;A. Blom
影响因子：
5.3
作者：
H. W. Liu
通讯作者：
H. W. Liu
影响因子：
5.4
作者：
B. Josefson;T. Svensson;J. Ringsberg;T. Gustafsson;J. D. Maré
通讯作者：
B. Josefson;T. Svensson;J. Ringsberg;T. Gustafsson;J. D. Maré
影响因子：
5.4
作者：
A. Hobbacher
通讯作者：
A. Hobbacher
DOI：
10.1007/978-94-007-6680-8
发表时间：
2013
期刊：
--
影响因子：
--
作者：
M. Kuna
通讯作者：
M. Kuna