A Reliability Modeling for Multi-Component Systems Considering Random Shocks and Multi-State Degradation

In practical engineering, uncertain failure modes can result in the system failure. To evaluate and enhance the reliability of multi-component systems, a general model is developed in this study, which considers two competing failure, the nonfatal failure and the catastrophic failure. The nonfatal failure is due to internal degradation damages from external uncertain shocks and the catastrophic failure is due to external extreme random shocks. The system is considered to be out of work in the situation that either the damage from random shocks or the total degradation exceeds the thresholds. Moreover, the uncertainty analysis theory for multi-state system is utilized to calculate the effect of uncertain shocks in the process of degradation. Two numerical examples are proposed to show the application. To demonstrate the influence of parameters on reliability, the sensitivity analysis is performed. Meanwhile, to verify the accuracy of the proposed model, the Monte Carlo Simulation is utilized here. The results of the proposed model are compared, and they accord well with the Monte Carlo Simulation.