Demand oriented system for the design of time allowances in railway operation (ATRANS 1)

• Applicant: Professor Dr.-Ing. Ullrich Martin
• Subject Area: Traffic and Transport Systems, Intelligent and Automated Traffic
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 257920233

As the framework for this research, and in order to make an efficient use of the railway infrastructure, a demand oriented system for the design of time allowances will be developed. The system includes a situation-specific algorithmization of the recovery and buffer times, thereby taking into account the dependence existing between recovery and headway-buffer times. In the timetable construction phase, radically different functions are used for the description of the recovery and buffer times. While buffer times are used for the reduction of secondary delays, recovery times are intended to reduce timetable related primary delays. In the operation phase, however, it can be observed, in comparison to the timetable construction phase, that there exists a complex interaction between these two components of time. For example, in the case of a train delayed by an earlier train upstream, there is the possibility that the delayed train is able to reduce its (secondary) delay through a downstream recovery time in subsequent train movements. This little example already shows the potential of suitable recovery time arrangement in regards to the quality of operation. Therefore, an objective of the research described in this application lies in the analytical formulation of the relationship between buffer and recovery times. However, in order to make this relationship usable for timetable construction purposes, route bundles are first identified. These route bundles consist of several individual routes in a given or generated route structure, between which exists a high temporal mutual dependence. Within these route bundles, the buffer and recovery times, based on the formulated analytical relationship, are going to be split among the involved number of trains in such a way that at a given quality of operation, the total consumption time (i.e. total blocking time + total buffer time), for the construction of the routes, is minimized. The temporal and spatial distribution of the buffer and recovery times is formulated through algorithmic general rules. If the total consumption time for the construction of routes can be reduced by adjusting the buffer and recovery times, then the difference would be available as a reserve for the insertion of additional routes. Thus through the optimization of the routes structure, in regards of the suitable allocation of the recovery time, an efficient use of the infrastructure can be achieved.The results obtained, within the framework of this joint project, are used as the basis for the development of other two projects, in which algorithms for the apportioning of freight demand on the system routes (ATRANS 2.2) and the evaluation of assignments (ATRANS 2.1) are considered.

• DFG Programme: Research Grants