目前,多数系统可靠型模型的建立,皆假设系统由相同的零件组成或者认为系统的所有零件承受相同的载荷。但多数情况下,系统由不同零件组成,每个零件承受不同的载荷。假设每个零件承受的载荷、强度均服从三参数威布尔分布。考虑系统中零件失效的相关性,在不作失效独立假设的前提下,对不同载荷进行归一化处理,基于可靠性干涉模型建立相应的串、并联系统静态可靠性模型。应用顺序统计量理论建立载荷多次作用时等效载荷的累积分布函数和概率密度函数,通过对不同等效载荷的归一化处理建立载荷多次作用下系统可靠性模型。运用蒙特卡罗方法对系统静态可靠性评价模型和载荷多次作用下系统可靠性模型进行了仿真实验,验证了该模型的正确性。
Most reliability models are developed on the assumption that the systems consist of the same parts and all the parts bear the same load. But in most cases, the systems consist of different parts and every part bears different loads. In present work, the stress and strength of each part were assumed to conform to the three-parameter Weibull distribution and failure dependence of the parts were taken into consideration. The static reliability models for series and parallel systems are developed based on reliability interference model by normalizing different loads without the precondition of failure independence assumption. Based on the order statistic theory, the cumulative distribution function and probability density function of the equivalent load under the effect of the load for multiple times were established, and the reliability models of failure-dependent systems under the effect of the load for multiple times were developed by normalizing different equivalent loads. The Monte Carlo method was then applied to the simulation experiments for the static reliability models and the reliability models of failure-dependent systems under the effect of the load for multiple times, and the results show that the model proposed is effective.