上层建筑端部结构疲劳试验与分析研究

疲劳评估的关键问题是选取准确的S-N曲线,为合理预报特殊部位结构的疲劳寿命,需要对特殊结构的S-N曲线进行验证,有效的验证手段是采用模型试验的方法进行研究。通过全船有限元分析计算,分析主要部位的应力分布情况,选取模型试验目标结构。根据关心区域的实际结构形式,结合试验条件设计目标节点疲劳强度试验模型。根据试验结果,以双对数线性模型进行S-N曲线绘制,并与规范S-N曲线进行比较,选取接近的S-N曲线对目标节点进行疲劳寿命预报。

Fatigue test and analysis of end of superstructure

The key point of the fatigue assessment is the selection of an exact S-N curve. The S-N curves of special structure need to be validated for the rational prediction of the structural fatigue life of particular positions. The model test method is effective for the validation. The stress distribution of the main structure is analyzed by the finite element calculation to select the target structure for the model test. The fatigue test model of the target node is designed based on the practical structure of the concerned region and the experimental condition. According to the fatigue test results for the target node, the S-N curve is drawn by the double logarithm linear model. The obtained S-N curve is then compared with the standard S-N curve to select the more precise one for the fatigue life prediction of the target node.