基于动态Copula统计拟合应力-强度相关性干涉的可靠性模型

RELIABILITY MODEL OF STRESS-STRENGTH CORRELATION INTERFERENCE BASED ON STATISTICAL FITTING OF DYNAMIC COPULA

为计算机械零部件在动载荷作用下的应力-强度相关性干涉响应可靠度问题,引入描述相关性的Copula函数和随机过程理论,建立动态可靠度计算模型。由于随机积分路径的复杂性,采取离散化思想将随机过程退化为随机变量,计算固定时刻下的可靠度;此外,采取函数拟合优化方法使可靠度数值连续化,基于模型复杂度及拟合残差筛选最优可靠度函数拟合方式。最后,计算验证了方法的有效性与可行性。

In order to estimate the mechanical components′ response reliability under interference of dynamic correlative stress-strength,the Copula function and random process theory were introduced to establish dynamic reliability model.Due to the complexity of random integral,the random process degenerates into random variable,and then the reliability at a fixed time was calculated based on the discretization thought.Furthermore,the function fitting optimization method was adopted to make the reliability value continuous.At the same time,according to model complexity and fitting residual,the optimal reliability function fitting method was selected.Finally,the typical verified example indicates the effectiveness and feasibility of this method.