Abstract
Over the past decade, there has been a notable increase in mathematical models for determining optimal intervention programmes – that is, those with the highest net benefits. These increasingly sophisticated models rely on an increasing amount of accurate infrastructure information, which is often not available for infrastructure managers. They are, therefore, confronted with the question of which data they should collect and what accuracy these have to have in order that intervention programmes determined with sophisticated optimisation model are reliably optimal. In this paper, it is shown how infrastructure managers can estimate the required information accuracy when determining optimal railway intervention programmes. The required accuracy of the input information is defined by determining the ranges of values over which (a) the optimal intervention programme does not change, (b) the optimal intervention programmes can be considered similar and (c) the net benefit obtained by an intervention programme can be considered near optimal. The ranges are determined for one variable at a time considering the estimated values of the infrastructure manager as default values. The method is illustrated for a railway line in Switzerland using a constrained network flow model to determine the optimal intervention programmes.
Highlights
One of the tasks of railway infrastructure managers is the development of intervention programmes – that is, the interventions to be executed on the railway infrastructure in the planning period and how they are to be combined (Adey, 2019)
This paper proposes a method for estimating the required accuracy of input information when determining optimal intervention programmes for railway networks using a mathematical optimisation model
The required accuracy is defined by the range of values of the input variables over which (a) the optimal intervention programme does not change, (b) the optimal intervention programme can be considered similar (c) and the net benefit obtained by an intervention programme can be considered near optimal
Summary
One of the tasks of railway infrastructure managers is the development of intervention programmes – that is, the interventions to be executed on the railway infrastructure in the planning period and how they are to be combined (Adey, 2019). They have to consider the different types of assets and interventions, their complex relationships, how their execution affects the service provided by the infrastructure and the available resources Optimisation models, such as the one presented in the paper by Burkhalter and Adey (2018), enable the determination of the optimal intervention programme considering all these aspects, where the optimal intervention programme is the one with the maximal net benefit. The net benefit considers thereby the costs related to and the benefits achieved by the execution of the interventions Such optimisation models require a large amount of infrastructure information that needs to be estimated and defined by the infrastructure manager, which is always coupled with uncertainties, meaning that the actual value of input variable may vary from its estimated value. There, the infrastructure manager had to determine the intervention programme for a realworld railway network consisting of a 17 km long single-track line (Figure 2)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
