Tackling freight derailment
The working group has participated in bowtie risk analysis workshops, to understand the risks, identify control measures for those risks, and to evaluate the strength of each control. The bowtie diagram resulting from those workshops illustrates that work. A report on the bowtie risk analysis was published in November 2016. This report describes the working group’s analysis of the most effective measures to be taken to reduce the risk of freight derailments. It is accompanied by a set of appendices that contain details of the methodology for the workshops.
The first interim report summarising the activities of the group was published in February 2016. For further information please also see the ORR report on 'Recent freight derailments: the interaction of track, vehicle and freight container load, and potential areas for improvements.' The second interim report, which provides a further update on the activities of the group was published in October 2017.
In April 2018, RSSB published a research report summarising the University of Huddersfield investigation of the effects of longitudinal and lateral offset loading on the risk of derailment for container-carrying-wagons travelling on twisted track. The work utilised multi-body vehicle dynamics simulations (such as VAMPIRE®) and resulted in proposals for new industry thresholds for offset container loads.
Most recently an updated freight derailment risk analysis report on risk of derailments due to combinations of track twist, wagon fault and offset load in container and hopper wagons was published by RSSB in May 2018. This is designed to support duty holders in assessing potential safety improvement projects. It is available to RSSB members on SPARK.