Project NONIs - development of optimized and sustainable insulated rail joint systems

Insulated rail joints are critical elements of the traffic control system that are submitted to heavy dynamic loads. Apart from turnouts, these joints contribute to about 40% of railway disruptions in Austria, significantly causing train delays. The objective of this project is to develop a more sustainable insulated rail joint system by investigating new design strategies and materials. This paper deals in the first instance with the analysis of data gathered from insulated rail joints by the measurement car of the Austrian Federal Railways. The data analysis is primarily based on the rail surface signal and longitudinal level signal. As the signals from the measurement runs are shifted in relation to each other, it is necessary to carry out a stationing process. After creating time series for 150 insulated rail joints, the 14 with a deterioration rate above 0.1 mm/year were defined as “Hot-Spots”. The comparison between these "Hot-Spots" and the entire data set indicates that insulated rail joints in tracks with concrete sleepers perform better than on those with wooden sleepers. The rail profile 49E1 is rarely represented in the tracks of the entire data set, but counts for almost the half of the "Hot-Spots", while the rail profile 60E1 seems to have a positive impact. The steel grade appears to have a rather small impact on the occurrence of “Hot-Spots”. However, the steel grades for the turnout areas were not available, which may affect this result. Further steps in the project are in situ measurements and the analysis of the newly obtained data, the design of a validated simulation model, the development, installation, and monitoring of a prototype. As a result, an intervention will be proposed in order to protect the ballast from high deterioration due to defect insulated rail joints.