The dissertation for obtaining a scientific degree of a Сandidate of Technical Sciences (Ph. D.), specialty 05.22.20 – operation and repair of vehicles. – Dnipro National University of Railway Transport named after Academician V. Lazaryan, Dnipro, 2020.
The dissertation contains the results obtained by the author, which together solve the scientific and practical problem of increasing the efficiency of transporting grain cargo by rail to seaports by improving the operating system of the rolling stock.
The aim of the study is to increase the efficiency of the wagon fleet in the transportation of grain to sea ports through the introduction of senders routing of wagon flows. The scientific results obtained in the thesis, as well as the developed methods, can be used to improve and evaluate the system of organization of wagon flows for the transportation of grain cargo by rail to ports for export, planning the distribution of grain cars for loading and traction rolling stock for grain trains.
More than 95% of Ukrainian grain export is carried out through seaports; more than 60% of grain cargoes are delivered to ports by rail. The analysis shows that the existing system of rail transportation of grain goods for export often shows its inefficiency. Among the main problems are the considerable dispersion and low loading capacity of the stations, the deterioration of wagons and the imperfect system of handling them, the shortage of locomotive traction, and the organization of transportation mainly by wagon consignments. One of the ways to increase the competitiveness of domestic grain on world markets is to build an effective system for operating rolling stock of railway transport in organizing export transportation.
The analysis showed that the existing elevator and port infrastructure, as well as its development dynamics, give reason to positively assess the opportunities for mastering promising volumes of Ukrainian grain export. Grain is transported from linear elevators to ports by rail (up to 70% of the volume), road (about 30%) and river (up to 3%) transport.
One of the key problems of the existing system of rail transportation of grain cargo is the significant dispersion of grain loading stations. One way to solve this problem is to concentrate loading grain at the nodal stations.
The dissertation found that rail transport is more competitive than road transport at distances of more than 150 km when transported in Ukrzaliznytsia wagons and at distances of more than 500 km in new own wagons. It was determined that the minimum additional costs that are associated with the accumulation of cargo for the route train are achieved with a period of 4 ... 6 days and a distance of road transport up to 30 km.
Given the stochastic nature of the railways work, it is advisable to use simulation modeling to evaluate the effectiveness of various options for the technology of rail transportation of grain cargo to sea ports. For this purpose, in the dissertation, the simulation model of freight transportation in the railway direction was improved by taking into account the possibility of organizing the movement of shipping routes from hub loading stations, in particular according to a schedule.
In the dissertation, a methodology has been developed for choosing nodal stations and concentration areas of grain loading for the formation of route trains, which is based on the use of cluster analysis apparatus, set theory and multicriteria optimization. This methodology allows to take into account both the set of infrastructural and technological parameters of the transport network and operational and economic criterions of effectiveness.
The task of forming loading concentration areas around the node stations is formalized as a multi-criteria optimization problem. In the final decision, 70 stations were included in 24 districts of grain loading concentration, which, with minimal additional costs, provides the maximum total volume of grain loading by route trains of about 7.5 million tons per year.
Studies carried out using the developed simulation model showed that the use of sender routing reduces the wagon turnover when transporting grain to the port by 27%, and the use of technology for the movement of route trains by schedule allows to reduce the wagon turnover by 50% and increase its productivity up to 2 times, by compared to carloads.
