STRUCTURAL RELIABILITY-ANALYSIS OF MARINE DIESEL-ENGINE SHAFTING SYSTEMS - AN EQUIVALENT STATIONARY PROCESS APPROACH TO THE LEVEL-CROSSING PROBLEM

This paper is concerned with the level crossing problem of a stress ab ove some limit. The problem arises when the structural reliability of a diesel engine shafting system is examined. The first excursion failu re probability is derived for the case that the stress on the shaft is a one-frequency cyclostationary random process. A new method is intro duced where the cyclostationary random process is replaced with an equ ivalent stationary one, defined to have an envelope process with the s ame upcrossing rate as the envelope of the original cyclostationary pr ocess. Both processes are assumed to have the same probability of upcr ossing a specific threshold. The agreement between this approach, whic h results in an analytical expression, and the ''exact,'' computationa lly time-consuming ''Markov approach'' presented in earlier work is ex cellent.