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- Smith, Andrew, et al.
(författare)
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Estimating the relative cost of track damage mechanisms : combining economic and engineering approaches
- 2017
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Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit. - : Sage Publications. - 0954-4097 .- 2041-3017. ; 231:5, s. 620-636
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Tidskriftsartikel (refereegranskat)abstract
- This paper proposes a new, two-stage methodology to estimate the relative marginal cost of different types of vehicles running on the rail infrastructure. This information is important particularly where the infrastructure managers wish to differentiate the track access charges by vehicle type for the purpose of incentivizing the development and use of more track-friendly vehicles.EU legislation requires that the European infrastructure managers set the access charges based on the incremental (marginal) cost of the running trains on their networks. The novelty of the approach derives from the combination of: (1) engineering simulation methods that estimate the track damage caused by the rail vehicles; and (2) econometric methods that estimate the relationship between the actual maintenance costs and the different damage mechanisms. This two-stage approach fills an important gap in the literature, given the limitations of the existing single-stage engineering or econometric approaches in obtaining the relative marginal costs for different types of damage.The authors demonstrate the feasibility of the method using 45 track sections from Sweden, for which the data on maintenance costs are available together with relevant track and vehicle data for 2012 (supplied by the Swedish Transport Administration). The authors demonstrate the feasibility of producing summary, section-level damage measures for the three damage mechanisms (wear, rolling contact fatigue, and track settlement), which can be taken forward to the second stage. The econometric results of the second stage indicate that it is possible to obtain sensible relationships between cost and the different damage types, and thus produce relative marginal costs by the damage mechanism and in turn the vehicle type. Based on this feasibility study, tracksettlement has been found to be the most expensive (in terms of maintenance cost) of the three mechanisms, followed by the rolling contact fatigue and then the wear. Future applications should focus on larger datasets in order to produce the required degree of precision on the estimation of the marginal cost.
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| 2. |
- Smith, Andrew S. J., et al.
(författare)
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Estimating the damage and marginal cost of different vehicle types on rail infrastructure : Combining economic and engineering approaches
- 2015
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Ingår i: Stephenson Conference Research for Railways 2015. - : Institution of Mechanical Engineers. - 9781510855830 ; , s. 265-274
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Konferensbidrag (refereegranskat)abstract
- EU legislation requires that European infrastructure managers set access charges based on the marginal cost of running trains on their networks. Two methods have been used in the literature for this purpose. Top-down methods relate actual costs to traffic volumes. Bottom-up methods use engineering models to simulate damage and then translate damage into costs based on assumptions about interventions and their unit costs. Whilst top down methods produce sensible results for marginal cost overall, they have struggled to differentiate between traffic types. The challenge for bottom-up approaches is how to translate damage into cost, with numerous assumptions being required which may be invalid. This paper proposes a new, two stage approach to estimating the marginal cost of rail infrastructure usage. The first stage uses engineering models to simulate damage caused by vehicles on the network. The second stage seeks to establish a statistical relationship between actual costs and damage. It is thus possible to convert damage estimates into costs using actual cost data, rather than through a set of potentially invalid assumptions as in previous approaches. Only the first stage is implemented in this paper. We show that it possible to produce total (annualised) damage measures for three damage mechanisms on five actual track sections in Sweden. Once extended, it will be possible to model the relationship between damage and actual costs for the first time; and thus better understand the relative costs of the different damage mechanisms and in turn inform the level and structure of track access charges.
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