船舶工程焊接接头完整性评估与疲劳寿命预测技术综述

介绍了船体结构中含缺陷的焊接接头完整性评估以及疲劳寿命预测方法,对结构完整性评估的K准则、COD准则、J积分准则、SINTAP/FITNET安全性评定方法以及评定流程、国内外标准进行介绍。并对焊接接头的疲劳强度影响因素,如平均应力、残余应力以及接头几何形状应力集中等进行了分析;介绍了焊接接头疲劳寿命预测的常用方法,如基于名义应力的评估方法、基于断裂力学的评估方法、基于损伤力学的评估方法以及其它疲劳评估方法等。此外,还对基于断裂力学法建立的焊接残余应力与疲劳裂纹扩展寿命之间的函数关系进行了介绍,该方法实现了对含残余应力的焊接结构疲劳寿命的精确预测。

A Review on Integrity Evaluation and Fatigue Life Prediction Technology of Welded Joint in Ship Engineering

Integrity assessment and fatigue life prediction of welded joints containing defects in hull structures are introduced, and the K criteria, COD criteria, J integral criterion, SINTAP/FITNET safety assessment method and process, and domestic and international standards for structural integrity assessment are introduced. The factors affecting the fatigue strength of welded joints, such as the average stress, residual stress and stress concentration in the joint geometry, are also analyzed. Common methods for fatigue life prediction of welded joints are introduced, such as nominal stress-based assessment methods, fracture mechanics-based assessment methods, damage mechanics-based assessment methods and other fatigue assessment methods. In addition, the functional relationship between the welded residual stress and fatigue crack extension life established based on the fracture mechanics method is introduced, which can realize the accurate prediction of fatigue life of welded structures containing residual stress.