Tracks - Articles and news items
Rail industry news / 7 September 2016 /
Britpave, the transport infrastructure association, has published a new report which calls for the examination of whole life cost benefits to be a perquisite for rail track investment and highlights the benefits of the concrete slab track
Rail industry news / 1 September 2016 /
The Mayor of London has marked 75 percent completion of Crossrail whilst on-board the first Elizabeth line station-to-station journey from Custom House to Canary Wharf.
Rail industry news / 21 June 2016 /
Loughborough University have issued an invitation to tender for the development of failsafe railway track switch.
Rail industry news / 30 June 2015 /
An £8.5 million research programme known as Track to the Future (T2F) has launched this month aiming to develop railway tracks for the future.
Issue 4 2013 / 1 August 2013 /
The liberalisation of European railways, particularly the free network access of passenger and freight traffic, have a basic influence on the construction of new lines and the maintenance and upgrading of tracks of ÖBBInfrastruktur AG. This article outlines the essential characteristics of track systems including track substructure.
Line layout and cross sections
Operating trains on a line that allows high speeds for passenger trains and low speeds for freight trains requires careful consideration about track alignment design. The maximum allowable values of cant deficiency (Imax = 130mm) and a max. cant excess (Emax = 110mm) enables expectable rail wear and reduced maintenance costs. A maximum gradient of 12.5‰ guarantees a load of 1,000 tonnes per freight train. A minimum radius of 3,000m enables a comfortable train speed of 200km/h, but 250km/h for trains with low axle loads is also possible.
The invention of the ‘Viennese Curve’ – a transition curve calculated for the centre of gravity of a vehicle – reduces lateral track forces and rail wear. In addition, this transition curve guarantees a full compensation of the rate of change of the lateral acceleration at the points of discontinuity – as a result, new and better passenger comfort will occur.
Issue 4 2013 / 1 August 2013 /
Since 2002, track strategies at the Austrian Federal Railways (ÖBB) have been based on life-cycle cost calculations1. These basic strategies have been adopted due to new technologies – for example the use of under sleeper pads, changing price levels, and the phenomena of rail contact fatigue2 (RCF).
The basic data for defining life-cycle cost based strategies are so-called standard elements. These standard elements are track sections with a set of defined parameters (traffic load, alignment, type of super-structure, dewatering system, sub-layers, sub-soil quality). For all relevant standard elements, working cycles have been worked out defining the demand of maintenance for the entire life-cycle and the economic service life. These cycles exist for different types of super-structure taking into account rail profile, rail steel grade, and the type of sleepers as there are concrete sleepers with under sleeper pads, conventional concrete sleepers and wooden ones (see Figure 1).
These standard elements are cross-checked with real track sections facing these parameters and with the information provided by a data warehouse showing the deterioration function of track over time based on time periods of 12 years.