Dynamic reliability modeling for system analysis under complex load

The traditional stress-strength interference (SSI) model regards the strength and the stress as two continuous random variables, but in practical engineering, the strength may be a stochastic degradation process. Besides continuous working load, a mechanical system often suffers from shock loads as well. How to calculate the dynamical reliability under complex load is a challenge that needs to be resolved. This paper proposes a generalized dynamic reliability model for the calculation of system reliability under complex load. The proposed model is available for system reliability problems under deterministic strength degradation or stochastic strength degradation processes. Six sigma and Gauss-Legendre quadrature formula are adopted to calculate the system reliability. A case study under three different conditions is presented to illustrate the application of the proposed model. The accuracy of the proposed method is compared with MCS.