Availability Approach to Optimizing Railway Track Renewal Operations

This paper proposes a multiobjective optimization approach for planning railway ballast, rail, and sleeper renewal operations. The objective is to support an informed decision that considers not only the railway track life-cycle cost (LCC) but also the track occupation times required to perform interventions. Two objective functions were minimized, as follows: (1)railway track unavailability caused by railway track maintenance and renewal operations, and (2)railway track components' LCC. Furthermore, to rationalize the renewal strategy, the model considers a multicomponent formulation that assesses, in time and space, the opportunistic combination of railway track renewal activities. A numerical application of the model on a real case study (Lisbon-Oporto line) is developed and discussed. The results show the interest of using this simple multiobjective optimization approach to obtain a decision-making process to support the scheduling of major railway track renewal works with an informed LCC-unavailability trade-off. (C) 2013 American Society of Civil Engineers.