Defining Degradation Processes of Switches Crossings for Maintenance Renewal Planning

Approximately 25 percent of the budget for the maintenance and renewal of railway tracks is used for the switches (points) and crossings (S&C). While in the mean time the budget expenditure for the maintenance and renewal of plain track is optimized with e.g. the help of decision support systems, for S&C this support stays rather rudimentary. One of the identified causes thereof is the lack of insight in the degradation and deterioration process of S&C. This study aims at identifying the relationships between degradation and/or deterioration and the use of S&C (amount of trains and their weight, speed etc.) including parameters which might influence this relationship, e.g. soil quality. Different databases from the Swiss Federal Railways are combined and several statistical techniques are used to analyse the results. The article presents the first results for complete S&C renewals.