载荷多次作用下材料的寿命分布及可靠性评估

Fatigue Life Distribution and Reliability Assessment of Material under Random Repeated Load

为对载荷多次作用下材料的疲劳可靠性进行评估,首先从随机载荷作用的统计学意义出发,基于顺序统计量理论建立了材料疲劳寿命的概率分布模型;然后考虑随机载荷作用次数的影响,建立了载荷多次作用下材料疲劳可靠性的计算模型;最后利用45#钢试样的疲劳试验数据对所建模型的有效性进行验证。结果表明:实验结果和理论分析结果接近,所建模型能够对材料的疲劳寿命分布及可靠性进行有效评估,对随机载荷多次作用下材料的动态可靠性评估具有一定借鉴意义。

In order to evaluate fatigue reliability of materials under random repeated load, the statistic meaning of random re-peated load is considered. Firstly, the probability distribution model of fatigue life of materials is constructed based on the or-der statistic theory. Then, the influence of random load action times is considered, and a fatigue reliability assessment modelis proposed. Finally, the validity of the proposed model is demonstrated by the experimental data of 45 steel. The result showsthat results are similar to the experimental results and theoretical analysis,and proposed model can effectively evaluate fatiguelife distribution and reliability of materials, and can provide some guiding significances for dynamic reliability assessment ofmaterials under random repeated load.