Multi-scale engineering of alkali-activated concretes for sustainable infrastructure

Lead Research Organisation: University of Leeds
Department Name: Civil Engineering

Abstract

Infrastructure is the foundation of the society and economy of every nation, and enables us to enjoy a high standard of living. Currently 3.5bn people live in urban areas, and this will continue to rise, particularly in developing countries, reaching 6.2bn people by 2050. The provision of infrastructure and housing poses great challenges to be resolved in the coming years, but also offers a unique opportunity to drive significant global change, with the development of cities and the improvement of living standards to eliminate poverty and promote social inclusion being essential for global economic growth.

The enormous amount of resources necessary to fulfil the world's infrastructure requirements, and the urgent need to mitigate climate change, mean that it is essential to move from traditional ways of providing infrastructure (which involve the use of cement, steel and other resources, and emit large volumes of CO2), to more sustainable ways. This will safeguard our future global society. The worldwide demand for Portland cement (a key component of concrete) has doubled in the past 10 years, to more than 4 billion tonnes per year, and this will continue to rise in the coming decades. This accounts for 8% of all worldwide CO2 emissions, and this could increase to as much as 25% by 2050. There is an urgent need for the UK, and the international community, to take up low-carbon best practices as we design and build infrastructure, so that significant reductions in carbon emissions can be achieved rapidly, and a shift towards a low-energy sustainable construction industry occurs.

This Early Career Fellowship research focuses on the design, characterisation and assessment of one of the most promising low-carbon candidates that can be used in place of Portland cement, to produce sustainable and durable concretes. These materials, called alkali-activated cements, can offer carbon emissions savings of 40-80% compared to Portland cement, when used to make a concrete with similar or better performance. However, despite this potential, the performance of alkali-activated materials in the field is unproven, and the processes that are now used for their production also face challenges that need to be resolved for the future-proofing of this technology. So, further research is urgently required to prove that these materials can be produced by sustainable processes using highly available resources, and then serve well under challenging conditions, over periods of decades or more. This particularly means that we must understand the ability of potentially damaging chemical species to move through alkali-activated cements (either through the material itself, or through any cracks which may form as the material shrinks or is damaged). This lies at the heart of the understanding of concrete durability, and requires the development of advanced modelling tools to predict the long-term performance of concretes that are made from these new cements, moving beyond the timescales that can be accessed in the laboratory to describe real-world performance.

The central aim of this Fellowship research is to provide the scientific basis for the use of the UK's natural resources, as well as by-products from other industries such as the production and processing of metals, to produce high-performance, high-durability alkali-activated concretes using conventional and/or novel processes. To achieve this, the Fellowship applicant and her team will use state of the art materials characterisation techniques to make connections between the way alkali-activated cements are produced, and their performance - moving the understanding 'from atoms to applications'. This will open a new pathway to building sustainable infrastructure for the future of the UK and worldwide, further strengthening the nation's current world-leading position in developing and using innovative cements, and opening opportunities for international connections and impact.

Planned Impact

The main beneficiary of this Fellowship research will be the construction industry, as this research will help remove barriers to the usage of alkali-activated cements and concrete in practical large-scale applications. Through partnership with the leading UK producer of alkali-activated/geopolymer cements, Banah UK, as well as European and global experts in waste valorisation, materials and construction technology such as FehS (Institut für Baustoff Forschung) and Zeobond Pty Ltd, impact will be optimised through direct transfer of results into application at all levels of the industry supply chain, from raw materials to finished products. Through partnership with these industry and commercial organisations, as well as the Swiss national laboratory EMPA (which is classified as an academic collaborator within the Fellowship research structure, but which nevertheless is extremely closely engaged with European and international industry), the Fellowship research results will be translated rapidly and effectively into state-of-the-art industry practice, in the UK and internationally.

The ability to accurately assess, predict and model the durability performance of alkali-activated cements and concretes, from a technically validated basis, will bring a very high degree of impact in both academic and industry circles. This information is the fundamental basis of performance-based standardisation, which are a crucial step to future development of standards enabling the use of innovative non-Portland cements in major infrastructure projects. The detailed modelling work which underpins this performance assessment will be disseminated through knowledge exchange workshops and direct engagement activities, including two specialised courses that will be delivered during the lifetime of the Fellowship research. The Fellowship team will also use these opportunities to gain input from partners and potential end-users regarding their priorities in terms of performance targets andkey degradation mechanisms for in-service applications, and will incorporate this feedback into the modelling work. The specific data underpinning these models will be made available to the developers of the international databases CEMDATA (thermodynamic data for cementitious systems), and SCEnAT and Ecoinvent (international references in the field of life cycle analysis) for inclusion in these widely used database tools, to maximise accessibility of the information to academic and industrial communities working on development and implementation of sustainable construction materials.

The Pathways to Impact plan also targets both social and technical aspects of implementing outcomes from the research in highly populated emerging countries such as Brazil, South Africa, India and Thailand through the current participation of the Fellowship applicant in Global Challenges Research Fund programmes. This will maximise the global impact of the Fellowship research, and will enable to identify future strategies for the development and application of alkali-activated materials, in different geographical regions. The academic aspects of this dissemination will also be linked to two major events, where the Fellowship applicant is part of the organising and scientific committees: ECI Second International Geopolymers Conference, Tomar (Portugal), May 2018, and the RILEM Week and Annual Cement and Concrete Science Conference, Sheffield (UK), September 2020, hosted jointly by RILEM Association and the Cementitious Materials Group of IOM3.
 
Description During the first 18 months of fellowship programme great progress has been made stablishing a new laboratory dedicated to the study of corrosion of steel embedded in concrete. My team and I have been instrumental in supporting the activities of UKCRIC Centre of Infrastructure Materials and Neville Centre of Excellence on Cement and Concrete, at University of Leeds, which has facilitated the development of collaborative research with other Schools within the University, and also has attracted new collaborations with industrialist and practitioners (e.g. Highways England). My team and I have commenced synthesis of low carbon cements, exploring alternative mix design to reduce carbon footprint, while controlling phase assemblage evolution. We are venturing in the next stages of the project developing novel manufacturing routes to produce low-carbon alkali-activated materials involving mechanical and thermal processes to produce reactive powders that will harden with water, similar to conventional cement. Outcomes of our research have been presented in national and international events, as well as publications in peer-review journals. We have also developed several engagement activities to create more awareness of the research we are developing and the importance of it.
Exploitation Route The preliminary research outcomes of this fellowship programme have been presented in national and international conferences, as well as in international specialised scientific committees to create awareness of the existence and success of my team, and also to demonstrate our capacity to deliver world-class research. In over the past six months we have dedicated significant efforts in increasing our engagement with general public/ business/ practitioners with very good acceptance. In the upcoming months my team and I will continue to nourish the new connections that we have developed with the aim of maximise the impact of the outcomes we are currently producing. Net-zero technologies are attracting great interest at present, and this is at the heart of this fellowship, so we will take advantage of this momentum.
Sectors Construction

 
Description CMMI-EPSRC RENACEM: Response to CO2 exposure of concrete with natural supplementary cementitious materials
Amount £449,643 (GBP)
Funding ID EP/T008407/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 07/2019 
End 07/2022
 
Description Design-for-manufacture of 3D concrete printed structural composites (DfM:3DCP)
Amount £577,525 (GBP)
Funding ID EP/S019650/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 06/2019 
End 06/2022
 
Description Maximising waste resources utilisation in future infrastructure development (WISE)/ Royal Society Exchanges 2019 Cost Share
Amount £11,400 (GBP)
Funding ID IEC\R2\192190 
Organisation The Royal Society 
Sector Charity/Non Profit
Country United Kingdom
Start 01/2020 
End 01/2022
 
Description Novel Approach for Vital Infrastructure Post Disaster/ International Programmes - Urban Infrastructure for Well-Being
Amount £251,352 (GBP)
Funding ID UWB190207 
Organisation The British Academy 
Sector Academic/University
Country United Kingdom
Start 11/2019 
End 11/2021
 
Description PERFoRM - Marie Sklodowska-Curie Individual Fellowship
Amount € 212,000 (EUR)
Organisation European Commission 
Sector Public
Country European Union (EU)
Start 06/2019 
End 06/2021
 
Title Exploiting in-situ solid-state NMR spectroscopy to probe the early stages of hydration of calcium aluminate cement - data 
Description NMR spectra. 27Al direct excitation spectra recorded as a function of time during the reaction of calcium aluminate cement with water at 20°C. 27Al direct excitation spectra recorded as a function of time during the reaction of calcium aluminate cement with water at 60°C. The first 27Al MQMAS spectrum recorded during the reaction of calcium aluminate cement with water at 20°C. The last 27Al MQMAS spectrum recorded during the reaction of calcium aluminate cement with water at 20°C. The last 27Al MQMAS spectrum recorded during the reaction of calcium aluminate cement with water at 60°C. 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? Yes  
 
Description Collaboration with Federal Institute for Materials Research and Testing (BAM - Germany) 
Organisation BAM Federal Institute for Materials Research and Testing
Country Germany 
Sector Public 
PI Contribution My team and I provide expertise in the area of alkali-activated technology, particularly in the development of alternative manufacturing routes to produce alkali-activated cements. As an extension of our research activities in this area, a recently funded Marie Sklodowska Curie Individual Fellow (Dr Juan Pablo Gevaudan), will study the interaction of steel with these novel materials, using a multi-technique imaging and spectroscopic approach using the UKCRIC Centre of Infrastructure Materials at University of Leeds, and will extend his research work evaluating the feasibility of applying newly developed electrochemical tests for assessment of steel corrosion in highly alkaline concretes.
Collaborator Contribution Colleagues at BAM will be hosting for 4 months a Marie Sklodowska Curie Individual Fellow (Dr Juan Pablo Gevaudan), who will be exploring the applicability of novel electrochemical techniques developed at BAM for the assessment of steel corrosion in highly alkaline environments. The objective of these secondment is to strengthen collaboration between colleagues at BAM and my team, including direct contribution to the activities both teams have committed to developed within the scope of the European Federation of Corrosion Task Group 11.
Impact The research activities of this collaboration will initiate in June 2019, hence we do not have output to report at this stage.
Start Year 2019
 
Description Collaboration with Universidad de La Plata (Argentina) 
Organisation University of La Plata
Country Argentina 
Sector Academic/University 
PI Contribution As part of an ongoing Royal Society Cost Share Exchanges grant with CONICET Argentina, my team and I will be conducting regular visit to colleagues at Universidad de La Plata for knowledge exchange in technologies enabiling maximise valorisation/ utilisation of construction demolishion wastes for development of low carbon, durable and economical concrete in Argentina and elsewhere. During the first visit this year, members of my team will participate in an open workshop on the topic of the grant. This will be followed by the visit of Prof. Yury Villagrant to U. Leeds later in 2020.
Collaborator Contribution Prof. Villagran has been instrumental in the preparation of a grant that has been successfully funded by Research Foundation Flanders (FWO) in collaboration between U. Ghent (Belgium), U. Graz (Austria), PSI (Switzerland) and U. Leeds, for the development and assessment of recycled aggregate hybrid concretes. This will enable to strengthen our research links and capitalise from the collaboration initiated through the Royal Society exchanges cost share grant.
Impact As this is a new collaboration no outcomes can be reported yet.
Start Year 2019
 
Description Partnership with Ghent University (Belgium) 
Organisation University of Ghent
Country Belgium 
Sector Academic/University 
PI Contribution I am named partners in a grant recently funded by the Research Foundation Flanders (FWO) where my team and I will contribute performing advance imaging in recycled aggregate hybrid concretes, for evaluation of the pore structure and chemical features characteristic of the interfacial transition zone between recycled aggregates and new concrete matrices. As part of these activities members of my team will be visiting U. Ghent, and we will host members of the projects in the UKCRIC National Centre for Infrastructure Materials.
Collaborator Contribution Colleagues at U. Ghent (led by Prof. Nele de Belie) lead this partnership through the project titled 'Carbonation performance of concretes with recycled aggregates and hybrid binders' funded by FWO.
Impact This is a new partnership and outcomes have not been generated yet.
Start Year 2020
 
Description Partnership with U. Texas at Austin (USA) 
Organisation University of Texas at Austin
Country United States 
Sector Academic/University 
PI Contribution As an extension of the relationship between U. Texas at Austin and my team, we have successfully securing an NSF-EPSRC lead agency grant (RENACEM, EP/T008407/1), evaluating the response of concretes with natural supplementary cementitious materials (SCMs) when exposed to CO2. This new project will sponsor research across U. Leeds, U. Sheffield and U. Texas at Austin until 2023. My team and I will centre on characterisation of UK natural clays/ soils to be used as potential SCMs and will develop the underpinning science required to understand the mechanisms leading to their potential degradation due to CO2 exposure.
Collaborator Contribution Colleagues at U. Texas at Austin are developing the knowledge and understanding required to identify processing technologies to maximise reactivity of SCMs, centred in assessing clays/ soils/ pumices abundant in the US. In collaboration with colleagues from Oregon State University and EMPA, the team and U. Texas at Austin will develop new models for service life prediction of concretes produced with natural SCMs, coupling thermodynamic and multi-physics modelling.
Impact This is a new partnership, hence no outcomes have been generated yet.
Start Year 2019
 
Description 2nd Meeting - RILEM TC 281- Carbonation of Concrete with Supplementary Cementitious Materials 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Study participants or study members
Results and Impact The 2nd RILEM Technical Committee (TC) 281-CCC meeting was held in TU Delft, The Netherlands during RILEM week. This international TC bring together expertise from academia, industry, practitioners as well as policymakers on understanding the response of modern concretes when exposed to CO2. As Deputy-Chair of the TC and coordinator of the Working Group in Carbonation of Alkali-Activated Materials, I presented some of the published results in the topic, as well as the outcome of an international round robin evaluating the feasibility of adopting different testing conditions, for assessment of performance of these materials. The presentation of these results sparked questions and discussions particularly from industry participants, as it highlights the needs of creating more suitable testing methodologies to determine performance of alkali-activated concretes when exposed to CO2. This has aided in motivation for the development of a critical review currently under preparation compiling existing data in the topic.
Year(s) Of Engagement Activity 2018
 
Description 3rd Yorkshire Cement and Concrete Science Symposium 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Professional Practitioners
Results and Impact 35 members of the Civil Engineering Materials Research Unit (U. Leeds) & Cements@Sheffield (U. Sheffield) attended this symposium, which included 10 technical presentations and a final discussion session to identify collaboration opportunities and synergies between the projects developed at both institutions. At present we are in the development of 3 grant applications with participation of both institution, and research from both teams will gain access to the facilities available through the Henry Royce Institute and UKCRIC, capitalising in recent government investments.
Year(s) Of Engagement Activity 2020
 
Description Colloquium in multi-scale characterisation of porous materials 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact In an effort of increase the visibility of existing new facilities and centres linked to my research (e.g. Bragg Centre for Materials Research, UKCRIC National Centre for Infrastructure Materials, Institute of Fluid Dynamics) this colloquium brought together attendees across different School of the Faculty of Engineering with interest in characterisation of porous materials. Although it was intended to be a small local event, we >40 attendees, really engaged with the activity. Several attendees have request to develop more activities such as this one, as it was well received to identify academics to develop potential collaboration projects, and also the facilities and support available, linked to the ongoing projects developed by my team.
Year(s) Of Engagement Activity 2020
 
Description Interview for The World - A co-production of the BBC World Service, Public Radio International and WGBH in Boston 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact This radio interview was centred in discussing greener alternatives infrastructure materials that can be used for production of sustainable concretes.
Year(s) Of Engagement Activity 2018
URL https://www.pri.org/stories/2018-07-19/concrete-production-uses-ton-sand-and-emits-lot-carbon-here-a...
 
Description Invited talk for the Microlab Colloquium - TU Delft - The Netherlands 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Around 20 academics, researchers and postgraduate students of the Faculty of Civil Enginering & Geosciences, as well as from the Netherlands Organisation for Applied Scientific Research (TNO) attended the Microlab colloquium, where I presented my research in utilising alkali-activated cements and concretes in extreme environments, such as encapsulation/ immobilisation of radioactive nuclear wastes. All attendees were very interested in the research outcomes presented, and made several questions about the chemistry of these materials and the advantages over other types of cementitious grouts. This discussion created major awareness of the applicability of these innovative cements in application beyond civil construction.
Year(s) Of Engagement Activity 2019
 
Description Invited talk for the Royal Academy of Engineering Research Day - Leeds City Region 2019 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact I was an invited speaker at the Royal Academy of Engineering Research Day organised by the Faculty of Engineering at the University of Leeds, presenting the new trends in infrastructure materials for 'cementing the future infrastructure'. I particularly emphasised the key role of concrete in our societal development, and also the great opportunities to increase sustainability of future infrastructure by development and adoption of low-carbon cements, such as alkali-activated materials. Several members of the audience from industry were particularly interested in the research I am conducting in this topic, and the advanced characterisation techniques available in the UKCRIC Centre of Infrastructure Materials housed at the University of Leeds.
Year(s) Of Engagement Activity 2019
URL https://engineering.leeds.ac.uk/events/event/362/royal_academy_of_engineering_research_day_-_leeds_c...
 
Description LafargeHolcim Research and Innovation Centre - Workshop on durability of low carbon concretes 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact LafargeHolcim is the largest produced of cement in the world with >250 cement plants across 75 countries. As part of their research portfolio to decrease the CO2 emissions associated with this industry, they are very interested in developing alternative/ low carbon solution that can be rapidly implemented and commercialised. This company invited a team of 5 international experts in alkali-activation technology, including me, to discuss research needs and the way forward to enable this technology to read a point of readiness that will enable its commercialisation at a global scale. Discussion about the future of low carbon concretes took place. A formal collaboration among my research team and LafargeHolcim will take place during the upcoming months through the development of grant proposals co-sponsored by this organisation.
Year(s) Of Engagement Activity 2020
 
Description The Conversation article 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Media (as a channel to the public)
Results and Impact This article intended to bring awareness to the general public of the properties and developments made in concrete technology, particularly when this material is exposed to extreme environments, through comparison of those environments with those created in the Star Wars saga. The article has been read >30000 and re-published in yahoo news, paidforarticles.com and uktopnews.com
Year(s) Of Engagement Activity 2020
URL https://theconversation.com/how-did-the-rebels-beat-the-empire-in-star-wars-the-answer-is-closer-to-...
 
Description University of Leeds research spotlight - Going with the flow, the hidden science of fluid dynamics 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact This article aimed to highlight the relationship between studying concrete durability and fluid dynamics principles, to highlight the multi-disciplinary and multi-scale approach required to understand how concretes interact and respond to the CO2 in the environment. This article has sparked conversation with colleagues from different disciplines to develop more accurate modelling tools for service life prediction of concrete structures.
Year(s) Of Engagement Activity 2020
URL https://www.leeds.ac.uk/spotlight-article/80/
 
Description University of Leeds research spotlight - Making concrete greener 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact This press release intended to create awareness of the research efforts my research and I are investing in developing low carbon materials for sustainable infrastructure development, linked to the ongoing research grants we are developing, including the EC fellowship. This article is featured in the main page of the School of Civil Engineering at U. Leeds and has given great visibility to my research to current and future students at all levels, as well as colleagues and broader audiences.
Year(s) Of Engagement Activity 2019
URL https://eps.leeds.ac.uk/collaborations-impact/doc/research-spotlight-making-concrete-greener