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Considerations on influences and interrelations between structural design and functional planning are imperative for raising the cost and operational effectiveness of marshaling yards in the context of managing wagonload services. This article focuses on multistage train classification, which rearranges a set of wagons from inbound trains to create a set of multigroup outbound trains in a proper form. Previous papers on the subject of multistage train classification were limited to considerations on the optimal classification schedule addressing the number of sorting steps as a primary objective. In contrast, this article proposes a model for overall optimization of the classification schedule and sidings layout, simultaneously addressing the number of sorting steps and the total number of wagon movements in the objective function. The model is created on a binary integer programming formulation. A Variable Neighborhood Search (VNS) heuristic is developed due to the computational complexity of the problem. Numerical experiments validate the formulated model and demonstrate the efficiency of the VNS meta‐heuristic approach.

Purpose: This paper considers the evaluations of project alternatives at the early stages of infrastructure project developments. Although it is expected to make important decisions at project early stages, it is rarely possible to obtain reliable data for exact evaluations. To deal with low quality data and the existence of uncertainties, this paper extends the evaluation problem to the fuzzy environment. Methods: We propose group decision making process for early stage evaluations of infrastructure projects. The evaluation approach utilizes combination weighting and compromise ranking. We integrate subjective and objective weighting methods to specify criteria weights. Afterwards, we use the VIKOR method to rank alternatives in the presence of conflicting criteria. Results: As a case study, we illustrate the evaluation problem within a railway line reconstruction project. Specifically, the proposed approach is efficiently applied to evaluate and rank several route alternatives considered within the reconstruction project of the regional line Pančevo-Vršac at Serbian railway network. Conclusions: The provided example illustrates the applicability of the proposed approach to deal with the evaluations at the early stage of the railway line reconstruction. The existence of uncertainties at early stages of project developments is common, so the proposed method is also applicable for other linear infrastructure in transport sector.

This paper examines a problem of forming the pick-up trains by conventional methods (the Futhner method and Special method), aiming at establishing basic characteristics of track facilities and values of shunting operations indicators important for evaluation of the effects of these methods application. The problem under consideration has so far not been examined in the literature to a sufficient extent, although in practice it has been proved to be necessary. For this reason, in this work a simulation study has been undertaken the results of which have to give the values and measures for assessing the quality of station/yard operations, as well as the assessment of new-designed station solutions

Multi-group trains have potential to take a substantial segment in realizing wagonload services. Multi-group train formation is a complex marshalling procedure which composes a train by sorting wagons according to their destinations. The order of wagons corresponds to the disposition of destinations on the train route. The determination of rational sorting schedules should be based on a comprehensive approach addressing different quantitative and qualitative indicators which are conflicting and uncertain. In order to address these conditions, we proposed a new approach for fuzzy multi-criteria evaluation of simultaneous train formation methods. In this paper we evaluate simultaneous train formation methods and provide recommendations for the rational application of elementary, triangular and geometric sorting schedules regarding different scales of sorting task complexity.