Background

Modelling freight transport is generally difficult due to the large spectrum of requirements and transport alternatives which exist. Most computational models are very aggregated; for example, the flow of goods is only studied in terms of tonnes and general average transport costs per tonne-kilometre for different transport modes.

In contrast, we wanted a model that allows disaggregated studies and is suited both for overall as well as more detailed analysis.

Our Solution

Transrail TSDA (Transport System Design and Analysis) is a computational model for analysis and design of freight transport systems. It lets you compare market potential for different systems out of a productional and technical standpoint, and to do resource planning based on market potential and expected transport volumes. However, the program may also be used to analyse the competitiveness of different transport modes for specific shipments and commodities.

The method of analysis centres on quantifying a transport scenario with wagonload (train), bimodal and truck transport, based on the goods flow. The scenario encompasses technical production units and transport routes for the different modes.

For each shipment and commodity, the analysis is done by

  • Computing transport cost based on available types of load devices (railway cars, bimodal units, trucks) with a detailed cost estimate for each mode.
  • Choosing a transport mode (wagonload, intermodal or truck) based on lowest cost, including a consideration of whether or not the load device will run empty or loaded on the return trip. Other criteria may be added.
  • Computing minimal empty transport of the load devices with a view to achieve a balanced system.
  • Computing flows of load devices in different relations and nodes in the transport network.

The cost estimates are so detailed that analyses can be done both on the basis of annual flows and for individual shipments.

A more detailed description of the TSDA model is available on request.