Scheduling preventive railway maintenance activities

In this paper we provide some useful methods for finding optimal track possession intervals for carrying out preventive maintenance works in such a way that the inconvenience for the train operators and the infrastructure possession time is minimised. In our models mostly the train free periods are used for carrying out routine maintenance works, namely the hours between two consecutive train operations. Moreover, we give an approach for the situation when these train free periods are not long enough for carrying out the track maintenance works. This is the case if projects have to be performed on some links. This paper puts forward a model aimed at scheduling in the best possible way the preventive railway maintenance works. Solutions to the model are developed using several heuristic approaches. These heuristics provides good solutions in a reasonable computation time.