System Reliability Under Time Varying Loads: I

This is the first part of an investigation of time variant structural system reliability under multiple loadings. The formulation of the problem in the context of outcrossing of a vector random process of a safe domain is examined. Methods of evaluating reliability of series systems and plastic frames are developed. Emphasis is on use of existing time invariant reliability methods and methods of load combination. Simple and well‐defined loading and structural systems are used to develop basic understanding of the problems. Extensive Monte Carlo simulations are carried out to verify the analytical methods. For the foregoing systems whose reliabilities do not depend on the loading sequence and loading path, a load coincidence analysis in conjunction with an efficient time invariant reliability analysis may give good, conservative estimates of the failure probability.