Research lead: Dr Rupert Myers
What is the problem?
Infrastructure systems are essential to society and underpin the nature of the built environment (spatial distribution, type, etc.), since they provide numerous basic services, e.g.: transport (road, rail, etc.); energy (electricity distribution and transformation, etc.); water (sewage, water treatment, etc.). Their high social importance, and characteristically long lifetimes and high initial investments, are key reasons why infrastructure systems are usually both constructed and operated by an organisation. E.g., the London Underground, initially constructed and operated by the Metropolitan Railway in the mid-1800s, is currently operated by Transport for London.
These key aspects distinguish the ‘product’ life cycles of an infrastructure system (Kia, Wong, and Cheeseman 2020), i.e., including construction, use, and end-of-life stages, as ‘service-oriented’ rather than ‘production-oriented’, whereas the latter is common to most other products, e.g., clothes and fast-moving consumer goods. Therefore, infrastructure systems already embody the core ‘service-oriented’ element of the circular economy. The key for a sustainable infrastructure system is thus to reliably deliver its social service(s) without excess cost(s) (to the managing organisation and society) and environmental impacts.
How does our research address this?
Opportunities to improve infrastructure systems exist along their whole life cycles. During use, regular field sampling and measurement of durability indicators should be implemented to predictively spotlight material degradation, enabling smaller targeted maintenance rather than larger and more costly repairs. Data-driven approaches and sensor technology will be key here, and provenance of infrastructure materials in databases will be built up. These data will underpin a good understanding of the quantity and quality of this ‘material bank’, which should be leveraged at end-of-life to facilitate reuse and recycling; the infrastructure manager will take on the role of a material supplier.
What have we achieved so far?
Here, the potential of reuse and recycling to reduce environmental impacts should be balanced with component and build complexity, e.g., modular/upgradable/replicable vs. in-situ/unique construction, since simpler materials and components are more readily recycled, and facilitate reduced construction complexity. This balance should also account for environmental benefits that may be achieved through use of multi-functional materials and components, e.g., permeable concrete (Kia, Wong, and Cheeseman 2020). Therefore, infrastructure systems should preferably employ simple and multi-functional materials and components, which in turn must be facilitated through good materials selection and design.
During the early stages in the design process, functional subsystems should be systematically developed to meet the social need(s)/service(s) of the whole infrastructure system, and, complementarily/concurrently, scenarios of their embodiments should be screened using life cycle assessments at this same (whole system) level. This use of life cycle assessment to authentically indicate environmental performance of the infrastructure system, i.e., of the (physical) ‘product’ life cycle rather than (conceptual) ‘project’ life cycle, must be driven/sought by the infrastructure owner-operator and facilitated by other key stakeholders (e.g., capital investors), and go beyond check-box type certifications: a sustainable infrastructure system must reliably provide its service(s) and meet both the specified product-based and project-based life cycle economic and environmental performance criteria. Ultimately, this assessment must demonstrate benefits to the owner-operator, material suppliers, designer, investors, and other key stakeholders along the infrastructure life cycle.
Related researchers: Rupert Myers, Arnab Majumdar, Chris Cheeseman
More information
- https://www.nature.com/articles/s41467-020-17583-w - CO2 uptake in cementitious materials over their lifetimes
- https://pubs.acs.org/doi/10.1021/acs.est.9b05550 - life cycle environmental impacts of alternative cements
- RICE project focuses on component-level substitution and associated changes in environmental impacts
- Assessing Material Efficiency in Buildings which focusses on building-level substitutions.
- SysTeM project – policy analysis of component-level substitutions in buildings to translate the research findings into policy recommendations
Related publications
- Pamenter, S., & Myers R.J. (under review) A review of measures to decarbonise the cementitious materials cycle. Journal of Industrial Ecology
- Kia, A., Wong, H.S. & Cheeseman, C.R. (2020) High-strength clogging resistant permeable pavement. International Journal of Pavement Engineering. 1-12 DOI: https://doi.org/10.1080/10298436.2019.1600693