Maintenance intervention optimisation for existing railway bridges

Maintenance of aging infrastructure is a burden on many organisational budgets, and Life Cycle Cost Analysis (LCCA) is accepted as an effective method to reduce these costs. However, LCCA becomes extremely complex when applied at the individual bridge component level within a large bridge population while considering multiple maintenance strategies, varying deterioration rates and intervention intervals. To address this concern, a decision support model is presented that proposes maintenance actions for future interventions based on a selection of maintenance strategies and given organisational budget constraints. The remaining service life of surrounding components is considered when assessing the most appropriate maintenance actions. Three popular bridge management strategies are considered in this model, comprising refurbishment, upgrade and renewal strategies. The infrastructure manager may apply one of these three strategies at the bridge level to estimate future network budgets or align with existing budgets. The developed decision support application allows "what-if' scenarios to be generated to determine life cycle costs by changing life gained from maintenance actions, maintenance costs, maintenance strategy, discount rate, intervention trigger time and minimum intervention intervals.