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.

Track properties for formation of pickup trains The problem of tracks for formation of pickup trains, with the analysis and proposal of possible solutions, is considered in the paper. Proposed solutions are derived from the results of simulations, which are based on the information obtained from the Belgrade and Lapovo marshalling yards. it was established that processes realized in these train stations are discrete with stochastic elements, and so the simulation models selected for solving this problem have been adapted accordingly, and have proven to be implementable and efficient. The results obtained show that the current practice in solving this issue has not been appropriate, that it does not provide good results and, hence, that it has to be changed.

Uvjeti za simultano formiranje višegrupnih teretnih vlakova Formiranje višegrupnih teretnih vlakova predstavlja jedan od kompleksnijih problema željezničkog prometa. Višegrupni vlakovi se sastavljaju od većeg broja grupa vagona koje treba sortirati u kompoziciju prema redoslijedu međukolodvora na pruzi. U radu je prikazana analiza tehničko-tehnoloških uvjeta koji bitno utječu na efekte primjene metoda simultanog formiranja vlakova. Razmatrani su efekti pojedinih metoda značajni za planiranje kolosiječnih kapaciteta i kvalitetu rada kolodvora. Istraživanje u ovom radu doprinosi procesu planiranja u cilju poduzimanja odgovarajućih mjera prije izgradnje kolodvora.