This paper deals with the use of Petri nets in modelling railway network and designing appropriate control logic for it to avoid collision. Here, the whole railway network is presented as a combination of the elementary models – tracks, stations and points (switch) within the station including sensors and semaphores. We use generalized mutual exclusion constraints and constraints containing the...

This paper deals with the use of Petri nets in modelling railway network and designing appropriate control logic for it to avoid collision. Here, the whole railway network is presented as a combination of the elementary models – tracks, stations and points (switch) within the station including sensors and semaphores. We use generalized mutual exclusion constraints and constraints containing the...

Ž . Swiss Federal Railways SBB inspect their railway tracks at regular intervals. The first step of track renewal planning is a geotechnical study. Inspection is focused on the thickness of the ballast, on subsoil material penetrating upwards into the ballast and on geotechnical properties of subgrade and subsoil materials. Up to now, the inspection has been done mainly by digging trenches at e...

The maintenance of railway track is highly relevant for the service quality and safety. This task demands huge technical and human resources. Therefore an optimal deployment of the available resources is crusial for the cost-effectiveness of railway operation. Furthermore, the track geometry maintenance activities need to be planned up to two years in advance. For this reason the French railway...

car body acceleration is an important factor affecting track safety and ride comfort, which are two primary aspects of railway systems. though track level is an important source of wagon body acceleration, no quantitative relation between them is available and the aim of this paper is to propose a method to address this issue. to do so, car body acceleration is determined using a 10 dof simulat...

In an open railway access market, the provisions of railway infrastructures and train services are separated and independent. Negotiations between the track owner and train service providers are thus required for the allocation of the track capacity and the formulation of the services timetables, in which each party, i.e. a stakeholder, exhibits intelligence from the previous negotiation experi...

This paper describes a new approach to optimisation of railway track maintenance and renewal works via genetic algorithms. Decision support systems and genetic algorithms are used in this study to optimise railway track maintenance and renewal activities. The results obtained in the scope of this study show that planned maintenance and renewal management systems can be developed and successfull...

The optimal track allocation problem (OPTRA), also known as the train routing problem or the train timetabling problem, is to find, in a given railway network, a conflict-free set of train routes of maximum value. We propose a novel integer programming formulation for this problem that is based on additional ‘configuration’ variables. Its LP-relaxation can be solved in polynomial time. These re...

Railway track-bed materials are mostly in unsaturated state, and their hydro-mechanical properties depend strongly on their water contents or suctions. In France, problematic soils such as collapsible loess and swelling marl can be origin of instability problems for new lines for high speed trains, while the hydro-mechanical behaviour of interlayer soil formed mainly by interpenetration of ball...

This paper features a method of synthesizing the track irregularities by which the alignment may be analytically represented by a pseudo-stochastic function, as well as the implementation of such a method in the numerical simulation of the dynamic behaviour of the railway vehicles. The method described in Part I relies on the power spectral density of the track irregularities, as per ORE B 176 ...