To further study the law of strength degradation, the residual strength degradation model is established based on the definition of fatigue damage, considering the interaction of various uncertain factors and time factors in service environment. Combined with equivalent damage model, a nonlinear cumulative damage model is proposed, which takes the interaction among loading loads into account and improves the accuracy of calculation. Additionally, the equivalent transformation of multistage load is studied using interval theory. According to the interval dynamic nonprobability reliability prediction model, a dynamic reliability analysis of the interval model is carried out. Dynamic reliability of the component is analyzed under multistage load accumulation damage to verify the effectiveness of the method.

中文翻译：

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基于强度退化的多级载荷下机械零件的区间动态可靠性分析

为了进一步研究强度退化的规律，在疲劳损伤定义的基础上，考虑了服务环境中各种不确定因素和时间因素的相互作用，建立了残余强度退化模型。结合等效损伤模型，提出了一种非线性累积损伤模型，该模型考虑了载荷之间的相互作用，提高了计算精度。此外，使用区间理论研究了多级载荷的等效变换。根据区间动态非概率可靠性预测模型，对区间模型进行了动态可靠性分析。在多级载荷累积损伤下分析了部件的动态可靠性，以验证该方法的有效性。