01.08.15
University of Nottingham researchers investigate use of ‘new materials’ for improving railway drainage
Source: RTM Aug/Sep 15
Dr Alec Marshall, lecturer in geomechanics at the University of Nottingham’s Department of Civil Engineering, writes for RTM on research into railway drainage systems, for which he is principal investigator.
Researchers at the University of Nottingham have recently begun a project to investigate the use of ‘new materials’ within rail-track drainage systems.
Reliable drainage solutions are critical for ensuring the long-term and cost-effective provision of railway infrastructure due to the detrimental effects of water (e.g. accelerated deterioration of ballast and loss of alignment). Ineffective drainage and excessive amounts of water may even cause catastrophic failure of railway infrastructure systems, which represent a real threat to public safety.
Much of the UK railway drainage infrastructure is old and in need of repair or replacement. In addition to current requirements, climate change is predicted to result in more extreme weather and flash flood events, which will put railway drainage systems under increasing strain, with more likelihood of disruption to rail services. The UK railway industry is also experiencing significant growth in the number of passengers and the amount of freight carried, which reduces the opportunities available to carry out maintenance. In light of these issues, railway drainage system modernisation is considered to be a key factor for improving railway network safety and capacity, and ensuring the infrastructure’s resilience to changing weather and climate events.
Current railway drainage, where it exists, tends to rely on ‘old technology’ – materials and methods that have been in use for decades. These methods can provide effective drainage, but their installation and maintenance is costly, and their long-term performance has been shown to be insufficient.
With modern advances in materials science providing benefits to many engineering sectors, the question arises – can a more modern approach to railway drainage improve things? The Nottingham researchers’ aim is to answer this question. They’ll investigate if and how more modern ‘new materials’ can be applied within railway drainage systems to improve performance and to reduce installation and maintenance time and costs.
Materials that have been recently developed will be assessed alongside those newly applied within railway drainage systems. The range of materials considered will include Expanded Polystyrene (EPS) – a lightweight and strong material with good chemical resistance.
The project team will use a range of experimental testing, including trials of a new material drainage system within a full-scale railway track model, as well as advanced small-scale physical modelling using the University of Nottingham geotechnical centrifuge. Numerical models will also be developed to gain a better understanding of the effects of key parameters within the drainage system.
An important component of the project is the development of tools to allow for the assessment of the full life-cycle costs of the developed new material drainage solutions. These tools will aim to help railway operators make informed decisions relating to the selection of track and drainage system maintenance and repair solutions. Advanced tools will also be developed which will provide a better understanding of the inter-relationships between railway drainage performance and other railway systems, including other infrastructure assets and rail operation services.
The project fosters a multi-disciplinary approach to developing engineering solutions, with expertise from several technical areas, including geotechnics, transportation infrastructure design and performance, as well as asset management.
The research team includes members of the Nottingham Centre for Geomechanics (NCG) and the Nottingham Transportation Engineering Centre (NTEC). The Nottingham team will be working closely with rail industry experts from project partners AECOM and Aspin Group, who will provide invaluable advice to help steer the project, as well as access to sites, equipment, and materials. The project will also benefit from involvement of staff from Network Rail.
The project is funded by the Engineering and Physical Sciences Research Council (EPSRC), the Department for Transport, and the Rail Safety and Standards Board (RSSB).
The successful completion of the project will allow the development of modern railway drainage solutions which incorporate new lightweight, easy to install, and cost-effective materials. The lifecycle cost assessment tools developed as part of this project will enable railway operators to make informed decisions about railway maintenance and repair, and ensure that end-uses of the railway get the best service possible.