Self-healing concrete ... being tested by ultrasonic pulse velocity apparatus.
Decarbonising the rail network
DR SAKDIRAT KAEWUNRUEN, Senior Lecturer in Railway and Civil Engineering at the University of Birmingham*, highlights to Gulf Construction measures that can help decarbonise railways and boost sustainability.
01 June 2020
While railways are a relatively low-carbon mode of transport, they will have to decarbonise completely in order to support the moves to achieve net zero emissions and to align with United Nations Sustainable Development Goals.
In meeting these decarbonisation targets, digital technologies will play a key role among a number of other aspects that need to be factored into the development of sustainable railway infrastructure, such as:
Sustainable and smart materials
There is much research currently being carried out that focuses on the development of eco-friendly construction and railway materials to produce cleaner and lower-carbon infrastructure. Such low-carbon materials include high-damping and self-healing concrete, 3D printed composites, self-sensing materials that monitor cracks and damage, and many more.
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Figure 1: End-of-life management framework of rolling stocks. |
Lifecycle performance & forensics
There needs to be sustainability-based management of infrastructure throughout the whole asset life. Key insights are derived from forensic investigations of each phase of the lifecycle – through design, construction, operation, maintenance and disposal of infrastructure assets. This research enables the decarbonisation of infrastructure and assets – decarbonisation that strikes the balance with economic, social and ecological concerns at the same time. The outcome of this research has been instrumental in the establishment of a new ISO standard for recycling of rolling stock (see Figure 1).
Infrastructure engineering & resilience
As one of the world’s largest specialist railway research, education and innovation centres, the University of Birmingham’s Centre for Railway Research and Education (BCRRE) is looking to revolutionise the design, construction and maintenance of infrastructure for operational readiness and resilience in uncertain settings.
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Figure 2: Advanced coupling 3D model of train-track-soil interaction for high-speed trains. |
To devise innovative solutions to the effects of extreme events and uncertain demands, it adopt principles of structural mechanics and dynamics in conjunction with field measurements and laboratory experiments. This is done in order to determine robustness, and the vulnerability and resilience of materials, components and structures, for example, to allow the interactions between the train, track and earth for high-speed train passing (Figure 2).
This outcome is critical in enhancing the service life of infrastructure whilst reducing waste and minimising the whole-life cost, energy, and carbon footprint.
These research results have been used for the development of two new ISO/BSI Standards for railway concrete sleepers and for railway plastic sleepers.
Reliability & risks
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Figure 3: Risk-based total track inspection framework over the life cycle. |
As safety is the first priority, reliability and uncertainty should be quantified in order to enrich the safety of infrastructure systems. This also manages risks to yield optimal safety margins in design, construction, maintenance and operation of infrastructure and assets. The insights obtained from research into operational disruptions, crisis responses, structural failures, and derailment risks are vital for the infrastructure assurance frameworks used by many rail authorities (Figure 3).
Artificial Intelligence & data sciences
The sustainable development of infrastructure needs to adopt data science, artificial intelligence (AI), and digitalisation (such as used for the digital twins of Kings Cross, a major railway hub in London), again with consideration for the whole life of the assets (Figure 4). There are a number of innovative and intelligent systems that help optimise total track inspections during disruptions; manage risks and safety at railway stations; benchmark resilience, operations and sustainability; and enable adaptive maintenance of rail infrastructure systems. Collaborating with multiple partners and infrastructure managers for these activities builds much more efficient and effective infrastructure systems, significantly reducing lifecycle cost, energy, and carbon footprint.
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Figure 4: Digital twins of Kings Cross Station to improve lifecycle cost and carbon footprint during operation and maintenance. |
The efficiency and effectiveness of the maintenance of railway infrastructure systems can be improved by considering lifecycle assessment, sustainability, and digitalisation.
A recent project on turnouts established a six-dimensional (6D) building information modelling (BIM) digital twin for lifecycle management of rail infrastructure systems. This so-called Level 3 BIM integrated six dimensions of field data information, based on Revit-2018 and Navisworks-2018 platforms. This was achieved by taking a regular three-dimensional design of the turnout and adding time schedule, costs and sustainability across the whole lifecycle.
The use of BIM for railway infrastructure systems has the potential to improve the overall information flow of planning and design; manufacturing pre-assembly and logistics; construction and installation; operation and management; and demolition of the asset. All of this means it is possible to achieve better performance and quality throughout the lifecycle. Based on integrated information of railway asset infrastructure, the 6D BIM has the ability to assess economic, management and sustainability parameters, and to achieve a balance among them. This insight will significantly benefit collaboration and communication among engineers, project managers, technicians, and senior management.
Net zero energy buildings
The goal of the BCRRE is to adopt digital twins to design, construct and maintain infrastructure systems in order to reduce energy usage to zero. Some work has already shown that retrofitting of existing railway stations can be carried out to achieve net zero energy building status. The BCRRE has helped the industry achieve near-zero energy use in new and existing buildings in railway networks, especially railway stations and office spaces.
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Track vibration ... symptoms of poorly-behaving infrastructure. |
Noise & vibration mitigations
Solving the causes of noise and vibration is a fundamental pillar in sustainability and decarbonisation, as noise and vibration are symptoms of poorly-behaving infrastructure. Excessive vibro-acoustic issues in railway and transport infrastructure can be resolved by using advanced simulations in relation with other previously mentioned themes including infrastructure engineering and resilience; sustainable and smart materials; and AI and data sciences. The BCRRE’s innovative solutions not only bring technological improvements to railway infrastructure but also result in social and well-being benefits to the users of railway.
Systems thinking for greener infrastructures
In addition to the technical speciality themes, we also need to make sure that the complex socio-technical context and a systems-thinking approach are taken into account fully for infrastructure decarbonisation. This will guarantee that externalities and social values are integrated at every stage of lifecycle in the sustainable development of critical railway infrastructure.
* The University of Birmingham’s Centre for Railway Research and Education (BCRRE) is considered to be well-placed to support national and international agendas for delivering decarbonisation, and its technology experts are already leading the way in developing solutions for railways around the world.
