摘要
为了在估算结构疲劳强度时计及残余应力释放的作用,合理地解释在以往焊接接头疲劳试验中不能解释的试验结果,借助三维弹塑性有限元法,研究了FPSO典型焊接接头在任意变幅循环载荷作用下的残余应力释放规律,建立了在任意变幅循环载荷作用下残余应力释放大小与残余应力和外载荷大小之间的计算公式,从而定量地分析了残余应力的释放,提高了疲劳强度估算的准确性和可靠性。
Structural members of FPSO＇s hull often undergo fairly large static loading before they enter service or variable amplitude cyclic loading when they are in service. The combined effect of applied stress and high initial residual stress is expected to cause the residual stress relaxation. Hence, the effect of residual stress relaxation must be considered for fatigue strength assessment of this kind of structure. In this paper, residual stress relaxation of some typical weld connections in ship-shaped structures is investigated with 3-D elastic-plastic finite element method. The relation of the magnitude of residual stress relaxation, residual stress and the applied load under variable amplitude cyclic loading is revealed. Through quantitative analysis of residual stress relaxation, the veracity and reliability of fatigue strength assessment are improved, and some fatigue behaviors of these kinds of weld joints in experiments could be explained reasonably.
出处
《中国造船》
EI
CSCD
北大核心
2008年第4期52-60,共9页
Shipbuilding of China
