Time-dependent reliability model of components with strength degradation based-on gamma process

In the evaluation of structural reliability, failure is defined as the event in which stress exceeds a strength that is liable to deterioration. A method is presented to consider stochastic loading and strength degradation for computing the time-dependent reliability of a structural component. The deterioration process is modeled as a gamma process, which is a stochastic process with independent non-negative increments having a gamma distribution with identical scale parameter. The stochastic process of loads is generated by a Poisson process. Numerical analysis of example shows this time-dependent reliability model provides accurate results.