中文摘要：

在常规可靠性设计方法的基础上，通过应用模糊数学理论，考虑弹簧应力和强度的不确定性，运用模糊可靠性方法对我国铁路货车新型变刚度弹簧组的模糊可靠度问题进行分析。针对新型变刚度弹簧组的疲劳试验方案，采用经典公式法和常规转换法，并结合数字仿真计算得出模糊可靠度结果。计算结果显示：标准试验方案下各弹簧可靠度均在96％以上；当量挠度试验方案下，除承载内簧可靠度较低外，其余弹簧的可靠度均在98％以上。研究表明，应用模糊可靠性理论评估变刚度弹簧组的可靠度是合理可行的，计算出的模糊可靠度具有较高的准确性。

英文摘要：

On the basis of conventional reliability design method, through the application of the fuzzy mathematics theory and consideration of the uncertainty of spring stress and strength, the issue of fuzzy reliability was investigated and analyzed for a new type variable stiffness spring assembly of domestic railway freight cars by using fuzzy reliability method. In view of the fatigue test project of new type variable stiffness spring assembly, the fuzzy reliability results were obtained by using classical formula method and conventional conversion method in combination with digital simulation. The calculation results showed that the reliability of all the springs was more than 96% under standard fatigue test project. The reliability of all the springs except the load bearing inner spring was more than 98% under equivalent deflection fatigue test project. The research revealed that the use of fuzzy reliability theory to evaluate the reliability of variable stiffness spring assembly was reasonable and feasible and the calculated fuzzy reliability achieved satisfactory accuraey.