随机载荷下材料疲劳寿命可靠性分析的智能仿真系统

将疲劳累积损伤看作是非稳态过程，摒弃了能量均匀耗散及线性累积损伤理论假设，采用神经网络技术准确描述其与材料性能、载荷应力间复杂的非线性映射关系，真实描述了材料疲劳损伤过程；建立了疲劳失效动态准则，综合考虑了材料疲劳性能及载荷的随机性，能够正确反映两者的个体性能及相互关系。并运用离散事件仿真原因，构造了材料疲劳可靠性分析的智能仿真系统，用以准确地进行疲劳可靠性分析。经正火35钢随机载荷疲劳试验验证，其可靠性分析精度较高。

INTELLIGENT SIMULATION SYSTEM FOR ANALYSING FATIGUE LIFE RELIABILITY OF MATERIAL UNDER RANDOM LOADING

Fatigue damage is regarded as an unstable process, and theoretical hypothesis of uniform energy dissipation, linear cumulative damage are avoided. Artificial neural network technology is applied to describe the complicate no linear relationship between fatigue damage, material properties and loading stress, so it can really depict the fatigue damage process of material. Dynamic failure criterion has been set up, which has comprehensively considered the random of material property and loading, it can be used to correctly reflect the individual characters and relationship between them. This paper also adopt discrete simulation theory to build an intelligent simulation system for analyzing fatigue life reliability of material. The test result has proved that the analysis accuracy is very high for normalizing 35 steel under random loading.