Development of railway ballast geometry index using automated measurement system

•A non-contact and automated ballast geometry inspection method was developed.•The new method performs more accurate and less time-consuming inspection of ballast conditions.•A new railway ballast layer geometry index was developed.•Using the new index, an improved/optimized maintenance approach was established.•It prioritizes required repair actions and provides more accurate allocation of machinery. Ballast layer Geometry condition is an important criterion in the railway track maintenance since the track stability strictly depends on the ballast geometry. Currently, a visual inspection is a method of monitoring ballast layer geometry which is considerably costly and time-consuming. Addressing the limitations of the current ballast maintenance approach, a new ballast layer geometry index was established, using an automated measurement system. This index is a function of deficits and excess of ballast in the track. A new maintenance approach was developed based on the new index, providing the possibility of quickly measuring ballast profile for faster and more accurate ballast maintenance. To examine the practicability and applicability of the new method/index, the results of a comprehensive field measurement were used. By illustrating the effectiveness of the new index in the field, it was shown that the new approach can significantly improve the current maintenance methods. It provides the possibility of fast and easy recording ballast layer geometry and maintaining optimum ballast conditions.