实测载荷谱疲劳裂纹曲线预测模型

PREDICTION MODEL FOR FATIGUE CRACK LENGTH UNDER REAL-TIME MEASURED SPECTRUM

采用历时8年实测载荷谱进行裂纹扩展实验,构建预测裂纹长度的新陈代谢模型并对比试验结果与预测结果在不同条件下的误差,分析结果表明:该模型结合无损检测技术,无需大量试验拟合材料常数即可有效预测裂纹长度,预测结果准确;能够减少载荷分散性和材料分散性对于预测结果的影响,大幅提高预测结果可靠性;该模型也可以应用于腐蚀疲劳环境中的裂纹长度预测。

In this paper,the crack propagation test was carried out under the real-time measured load spectrum for eight years. A metabolic model is constructed to predict crack length and the errors between the experimental results and the predicted results under different conditions is compared. The analysis results show that the model,combining with nondestructive testing techniques,could effectively predict crack length without fitting the material constants using a large number of tests. This model can also reduce the influence of load dispersion and material dispersion to prediction results,so that it greatly improves the reliability of prediction results. Moreover,this model can be applied to predict crack length in corrosion environment.