ABSTRACT
A probabilistic framework is set up to assess the fatigue life time of structures such as the pipe networks in the nuclear power plants. It incorporates all kinds of uncertainties appearing in the design such as those on the material fatigue strength, structure loading, mechanical model, etc. The paper presents in details the statistical treatment that allows to define probabilistically the number-of-cycles-to-failure of a specimen at constant stress amplitude. Then the random cumulative damage due to random loading and random fatigue strength is defined and two ways to compute it are proposed. They reveal equivalent under certain assumptions. An application example including both kind of randomness is finally given.
