Time dependent reliability analysis of railway sleepers subjected to corrosion

摘要

Prestressed concrete sleepers, as a major component of railway infrastructure, are prone to many environmental deterioration or load induced damages during their service lives. Therefore, an accurate prediction of their remaining service life is of paramount importance for proper allocation of maintenance management budgets. In this study, the remaining cross sectional area of corrosion affected prestressing wires is modeled as a nonstationary Gaussian process while other time-invariant uncertainties, that is, geometrical properties and load affects, are modeled as random variables. Hence, the timed-dependent reliability of these assets are calculated using the first passage theory and the corresponding outcrossing rate of the stochastic process from the safe domain. The merit of this analytical method is its efficiency and accuracy in perdition of remaining service life. The applicability of this method is shown on a B70 PSC sleeper designed based on UIC-713 code and it is found that pitting corrosion in chloride-laden environment extremely diminishes the service life of these assets.