Optimal inspection plan for deteriorating structural members using stochastic models with application to buried pipelines

The deterioration of structural systems is unavoidable after their long time in service. To ensure the safety of these systems, an effective inspection strategy with a minimal cost is essential. This paper presents an analytical approach for determining the optimal inspection plan using a cost-based criterion in which structural damage and failure are modeled as stochastic processes. This allows the consideration of the correlation of damages at different times in the reliability-based inspection plan. An example is provided to illustrate the application of the proposed methodology, taking the number of inspection actions and the critical damage level at which repair is performed as the optimization variables. The proposed procedure provides a fast solution for the optimization of an inspection plan with superior performance over those based on simulation. In addition, correlation has a big impact on the result of an optimal inspection plan matching that of the cost of failure. © 2019 American Society of Civil Engineers.