LEA's chemistry of cement and concrete - 2019.pdf

Lea’s Chemistry of
Cement and Concrete

Lea’s Chemistry of
Cement and Concrete
Fifth Edition
Edited by
Peter C. Hewlett
PhD, LLD, BSc, CChem, CSci, FRSC, FIMM, FInstConcTech, FConcSoc
Martin Liska
PhD (Cantab), MSc, A.M.I.C.T.

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Author Biographies
Peter Clive Hewlett is a chartered chemist and scientist turned materials scientist. He is a
Fellow of the Royal Society of Chemistry, Institute of Materials, Minerals and Mining,
Institute of Concrete Technology and the UK Concrete Society.
He combines commercial research in the construction materials sector with academe and
has done so for over 50 years. He has lectured and published extensively and has several
patents. He has held a visiting industrial professorship at the University of Dundee for over
30 years and has an honorary Doctor of Laws degree (Honoris Causa) for work on concrete
durability and surface characteristics. He holds the UK Concrete Society Gold medal (2006)
and is Chairman of the Editorial Board of the Magazine of Concrete Research.
A past President of the UK Concrete Society and Institute of Concrete Technology.
He spent some 25years as researcher and Director of Cementation Research Ltd. before
joining the British Board of Agr
ement as Chief Executive Officer in 1988 dealing with inno-
vative construction products. Past president of the European Union of Agr
ement and the
European Organisation for Technical Approvals.
He was Editor and an author of the fourth edition of Lea’s book and is co-editor of the
fifth edition.
Martin Liska graduated at VSB Technical University of Ostrava, Czech Republic with an
MSc in Mineral Resources. He obtained a PhD degree in the Department of Engineering at
the University of Cambridge, where he studied the fundamental properties and applications
of reactive magnesia cements. Martin then continued at the same institution as a Post-
Doctoral Research Associate to study novel cementitious binders, their fundamental and
engineering properties in a number of geotechnical and geo-environmental applications.
He then moved into the construction industry to work closely with Professor Peter Hewlett
at the David Ball Group, as Research and Development Manager, on alternative binder con-
crete systems based on alkali-activation. This fruitful collaboration has resulted in a pat-
ented technology which is being currently exploited commercially. Martin currently
works as Research and Development Manager at Sika UK. He is responsible for the devel-
opment and deployment of admixtures for concrete and a broad range of cementitious and
hybrid systems, addressing fundamental as well as engineering performance, economics and
sustainability criteria. Martin is the author/co-author of 29 scientific publications and 4
patents. He is a member of the Technical and Educational Committee of the Institute of Con-
crete Technology and is a Board member of the Magazine of Concrete Research.
xix

Pierre-Claude Aı̈tcin is a Professor Emeritus at the Department of Civil Engineering of the
Faculty of Engineering of the Universit
e of Sherbrooke, P. Qu
e., Canada.
He is honorary member of the American Concrete Institute. He received from the
American Concrete Institute the Artur Anderson Award in recognition of outstanding lab-
oratory and field research on the composition, structure and properties of HPC, superplas-
ticisers and silica fume.
From 1990 to 1998 he was scientific director of the Canadian network of centres of
excellence on high performance concrete. In 1998 he participated to the construction of
the cyclo-pedestrian bikeway of Sherbrooke, the first structure built with a Ultra High
Strength Concrete.
He is the author of several technical books on concrete technology
High Performance Concrete (translated in French, Portuguese, Spanish and Check)
Binders for Durable and Sustainable Concrete
Sustainability of Concrete
The Science and Technology of Concrete Admixtures
James J. Beaudoin has been involved in cement and concrete research at the Institute for
Research in Construction (IRC), National Research Council (NRC) of Canada since 1972.
He was elected a Fellow of the Royal Society of Canada in 1999 and received an honorary
doctorate (LLD) from the University of Windsor in 2000. He was awarded a Gold Medal and
appointed Researcher Emeritus by Dr. Arthur Carty (former National Science Advisor to the
Prime Minister) in 2003. He was Head of the Materials Laboratory at IRC from 1989
to 1997.
He was a Principal Researcher for the Ottawa Centre of the Canadian Network of
Centers of Excellence on High Performance Concrete (1990–1998) known as Concrete
Canada. He has served as an adjunct Professor of Civil Engineering at the University of
Ottawa and the Universite Laval since 1987. He led the cement-based nanotechnology
research team at IRC starting in 2003. He was instrumental in bringing the 12th International
Congress on the Chemistry of Cement to Canada in 2007.Dr. Beaudoin continues to have a
significant impact on NRC research pertaining to the nanoscience of cements with his work
on the metamorphosis of C-S-H nanostructure, the development of C-S-H-based nanocom-
posites and the evolution of composition-based models for C-S-H nanostructure. A tribute
symposium was held in his honor in 2014 at the American Concrete Institute meeting in
Washington. He received the ‘Della Roy Lecture Award’ in 2005 at the American Ceramic
Society Annual Meeting. He was also awarded the Copeland Award of the American
Ceramic Society in 1998.Dr. Beaudoin is the author or co-author of five books and
numerous book chapters, encyclopaedia contributions, research journal papers and patents.
John Bensted read Chemistry for his BSc and PhD degrees at the University of London,
before joining Blue Circle Cement at its research division in Greenhithe, Kent. Here he spent
over 17years in research, development, quality control and technical troubleshooting
worldwide for the group’s entire range of cement types. He rose to become a principal sci-
entist, and was awarded the DSc degree of the University of London for his cement research
work. In 1985 he joined British Petroleum at their Sunbury Research Centre, initially as a
senior drilling engineer before becoming a research associate. He directed research pro-
grammes on oilwell cement and functioned as an internal consultant for all aspects of
cement technology for the different BP businesses worldwide. Since 1992 John has become
more involved with academic research in cement and concrete technology as a visiting pro-
fessor at the University of Keele, Greenwich and London (Birkbeck College). He acts as a
consultant in cement technology, operating internationally.
xx Author Biographies

Jannie S.J. van Deventer completed doctorates in chemical engineering, mineral pro-
cessing and business economics in South Africa, where he was Head of Chemical Engi-
neering at the University of Stellenbosch. In 1995 he became Professor of Mineral and
Process Engineering at the University of Melbourne. From 2003 to 2007 he served as Dean
of Engineering. Since 2010 he is an Honorary Professorial Fellow and continues research
into chemically activated cement and mineral processing. Since 2006 Jannie has been the
CEO of Zeobond, which has commercialised low CO2 concrete using activation chemistry.
He previously commercialised computer vision technology in the mineral industry, and con-
tinues to be involved in the commercialisation of metal extraction processes. His publication
record of more than 700 papers includes more than 300 journal papers, many of which are
highly cited. He has received many awards for his research in both mineral processing and
concrete science, and continues to serve on several editorial boards.
Thomas Daniel Dyer is a materials scientist working in the field of civil engineering. He is
senior lecturer within the Discipline of Civil Engineering at the University of Dundee in
Scotland and a member of the Concrete Technology Unit at Dundee.
His research interests centre around the chemistry of cementitious materials, with par-
ticular emphasis on their role in controlling the durability of concrete. Areas of research
have included an examination of the influence of fly ash on the mass transport and chloride
binding properties of concrete, the use of pozzolanic materials to control alkali-silica
reaction. He has published widely in academic journals, contributed towards chapters in
books, and written two books: ‘Concrete Durability’ and ‘Biodeterioration of Concrete’.
Rodney M. Edmeades graduated in Chemistry in 1953 and, following an intensive tech-
nical training course, worked in the cement industry (Blue Circle Group) for 11years.
Joining Cementation Research in 1964, he was appointed a Director in 1977 in charge of
the Materials Technology Section. His work at the time encompassed the investigation
of cement hydration mechanisms and the interaction of admixtures, together with the devel-
opment of materials used in civil engineering, concrete repair, ground engineering and
mining. He co-authored a number of papers and was elected a Member of the Institute
of Concrete Technology in 1988. In that year as a result of a company reorganisation he
became an Associate Director of Trafalgar House Technology, responsible for Construction
Materials, and acted as Senior Consultant to various group units prior to retirement in
May 1995.
Author Biographies xxi

James I. Ferrari is an experienced geomaterials scientist with the Materials and Structures
department at RSK Environment, where he leads the petrography team. He graduated with a
degree in Geology from Keele University in 2008 and joined STATS Limited (now part of
RSK Environment) in the same year. James specialises in the petrographic examination and
consultancy of a wide range of geomaterials used in the built environment including aggre-
gates, stone and slate, concrete and other cementitious materials. In addition, he has expe-
rience in a wide range of physical/chemical testing methods applied to the evaluation of
constructions materials. James has authored a wide range of unpublished commercial
reports addressing subjects including aggregate quality and suitability, AAR assessments
of aggregates and concrete, fire-damaged concrete and many other forms of concrete dete-
rioration. He is an active member of the Applied Petrography Group (affiliated with the
Engineering Group of the Geological Society), and since 2014, has been involved in British
Standard Institute committees for the development of aggregate testing standards. James is
expecting to gain his chartered geologist status in early 2018.
Per Fidjestøl graduated from Norwegian Technical University in 1973 with a degree in
Civil Engineering. He joined Det Norske Veritas working in the area of offshore and marine
structures, including cold climate technology. His main role, however, concerned concrete
technology. In 1986 he joined Elkem Materials and has been engaged in a variety of capac-
ities, mainly related to RD, marketing and technical support in the area of microsilica for
concrete. Per was a fellow of ACI and a member of several technical and board-appointed
committees, including Chairman of the International Activities Committee. He has pub-
lished about 50 technical papers mainly on corrosion and/or microsilica. He was a member
of CEN groups related to microsilica, and was a member of ASTM C-9 on Concrete and
D-18 on Geotechnics.
Herv
e Fryda studied material science at Universit
e Pierre et Marie Curie, Paris, and
received a PhD from Ecole Sup
erieur de Physique Chimie Industrielle in Paris in 1995
on the use of calcium aluminates cement for nuclear waste trapping. After 18 months at
Imperial College, London, he joined the Lafarge group in 1995 to conduct upstream
research on calcium aluminates. He joined Kerneos in 2000 where he has been in charge
to develop new products for different applications (refractory concrete, construction … )
until 2012. From 2012 to 2016 he took the lead of a research group on more fundamental
research on calcium aluminates (hydration, mineralogy, bio deterioration …). Since 2016 he
is Director of Kerneos Research Center in Vaulx-Milieu, France.
xxii Author Biographies

Thomas (Tom) Harrison is an independent consultant and Visiting Industrial Professor at
the University of Dundee. After a period working for contractors in the United Kingdom and
then for a small design office in Canada, he joined the Cement Concrete Association in its
Construction Research Department. During this time he achieved a PhD on formwork pres-
sures. He became the Head of Construction and Technology in 1987 when the CCA
became the British Cement Association and then its standards manager. In 1993 he was
head-hunted to become the Technical Director of the British Ready-Mixed Concrete Asso-
ciation where he remained until reaching retirement age. He was chairman of the European
Ready-Mixed Concrete Organisation’s technical and environmental committee for 14 years,
chairman of the BSI Concrete committee for 19 years and actively involved in European and
International standardization. While in the process of reducing his CEN activities, he still
convenes two working groups and one task group. His other activities including writing pub-
lications, acting as an expert witness and being a member of the Board of the Magazine of
Concrete Research.
Arthur Michael Harrisson graduated in geology from the University College of Wales,
Aberystwyth in 1974 and worked for a period with the Institute of Geological Sciences,
now the British Geological Survey, managing drilling programmes and publishing reports
on the assessment of industrial minerals. In 1979 he joined Blue Circle Cement’s Research
Department, where he began a long standing interest in clinker microscopy. During this
period he established and managed a scanning electron microscopy laboratory which carried
out innovative work on clinker mineralogy and cement hydration mechanisms. Since then
he has worked with a number of cement manufacturers both in the United Kingdom and in
several other countries including New Zealand, Malaysia, Australia, Ireland, South Africa
and Spain, either as an employee or as a consultant. His work has included five years as plant
chemist and a similar period as Chief Chemist for Rugby Cement. He has also spent time as a
consultant with Mott MacDonald consulting engineers writing specifications for high per-
formance concrete and acting as expert witness. He now specialises in the assessment of
mineral deposits for use as cement clinker raw materials as well as quality and environ-
mental issues. He currently operates a consultancy from a base in North Wales carrying
out a range of construction industry related projects, primarily raw materials assessments
and clinker microscopy. He has published widely over the years and is a regular contributor
to the International Cement Review.
Duncan Herfort is Chief Scientist at Cementir Holding and Aalborg Portland with global
responsibilities for RD, quality and technical services. As a geologist and geochemist,
with 30years’ experience in the cement industry, he has developed a special interest in
applying high temperature mineralogy and thermodynamics to the challenges faced by
the cement industry. Additional, longstanding activities and responsibilities include regular
lectures for the European Cement Research Academy and the University of Toronto’s
course in Cement Chemistry, industrial advisor to Nanocem, member of the Board of
Editors for Cement and Concrete Research, Guest Professor at the Chinese Building Mate-
rials Academy. He was awarded the fourth Klaus Dyckerhoff prize in 2014.
Author Biographies xxiii

Jason Henry Ideker is an Associate Professor at Oregon State University and Co-Director
of the Green Building Materials Laboratory. He holds a BS in Civil Engineering from The
Georgia Institute of Technology and an MSE and PhD from The University of Texas at
Austin. Dr. Ideker’s main research areas are in service-life of concrete with a focus on
early-age behaviour of high performance cementitious materials, mitigation and test
methods for alkali-silica reaction and durability of calcium aluminate cements. Dr. Ideker
and his group do transformational research where fundamental results are implemented into
improved test methods and specification development. Dr. Ideker is a member of ACI Com-
mittees 201, 231 and 236. Ideker is a co-author of ACI 201.2R-16 Guide to Durable Con-
crete. He is a recipient of the ACI Young Member Award for Professional Achievement. He
is a member of ASTM C01 and C09, and serves on the Executive Board of C09. He chairs
ASTM Subcommittee C09.50—Risk Management for Alkali-Aggregate Reactions. He is
also a member of the RILEM TC258 Avoiding Alkali Aggregate Reaction (AAR) in
Concrete—Performance Based Concept. Dr. Ideker is a three-time recipient of the PCA
Education Foundation Fellowship. Along with Professor Karen Scrivener their International
‘Corvallis Workshops’ has brought together industry, practitioners and academic
researchers to improve concrete performance in three meetings since 2011. Ideker has
authored over 80 publications including peer-reviewed journal articles, research reports,
conference proceedings and book chapters.
Martyn Roderick Jones is Professor of Civil Engineering at the University of Dundee,
Scotland. He is a Charted Civil Engineer and member of the Institution of Civil Engineers.
He serves on CEN committee TC51/104 WG 12 TG5 and is a Board member of the Con-
struction Scotland Innovation Centre. He is an active researcher in the field of cement
science and concrete technology and publishes widely. His work tackles issues of sus-
tainable concrete construction, durability and performance, with a particular focus on estab-
lishing materials appropriate for practical industrial applications.
Harald Justnes is Chief Scientist at SINTEF Building and Infrastructure, Department of
Architecture, Building Materials and Structures. He has been with the Foundation for Sci-
entific and Industrial Research (SINTEF) since 1985. His field of interest covers the chem-
istry of cement, concrete, admixtures and additives (including polymers) from production,
through reactivity, to durability. He was educated at the Institute of Inorganic Chemistry,
Norwegian University of Science and Technology (NTNU), and is now Adjunct Professor
in ‘Cement and Concrete Chemistry’ at Institute of Materials Technology, Section for Inor-
ganic Chemistry, NTNU.
Justnes has been visiting Professor at China Building Materials Academy (CBMA),
Beijing, China, and was appointed Honorary Professor at Xian University of Architecture
and Technology, Xian, China, in 2007.
Related to his contribution to this book, he was award for Outstanding Contributions in
the Development of Chemical Admixtures for Use in Concrete presented at the Sixth
CANMET/ACI International Conference on Superplasticizers and Other Chemical Admix-
tures in Concrete, Nice, France, 2000.
Justnes has authored or co-authored more than 330 papers in journals and conference
proceedings and has been member of the Editorial board of the International Journal Cement
and Concrete Composites, Elsevier, since 2003.
xxiv Author Biographies

Siham Kamali-Bernard is graduated in Civil Engineering from the Ecole Nationale des
Travaux Publics de l’Etat (ENTPE) in 1998 and from the Ecole Normale Sup
erieure de
Cachan (ENS Cachan) in 2003 in France. In 1999, she joined the research team of Professor
Micheline Moranville-Regourd at the LMT-Cachan to prepare her PhD thesis on the
leaching of cementitious materials (experiments and modelling) with the support and the
collaboration of Electricity of France (EDF). From the end of 2003 to 2006, she worked
with Professor Denis Damidot at the Ecole des Mines de Douai, now Institut Mines Telecom
Lille-Douai, on thermodynamical modelling of cementitious systems. She is currently Asso-
ciate Professor at the National Institute of Applied Sciences of Rennes where she continues
to develop research on the microstructure characterisation, mechanical and transport prop-
erties as well as durability of cementitious materials using both experimental and multi-
scale modelling approaches. She has supervised several PhD thesis and has published about
45 international papers on cementitious materials. She is a regular contributor to the Inter-
national Cement Review.
John Lay is Product Quality Director for CEMEX UK Cement and Building Products. He is
a Chartered Chemist and has worked in technical roles for ready mixed concrete, aggregates,
asphalt, cement and building products. He has been involved in British and European stan-
dardization for many years and is a former chairman of the CEN Technical Committee 154
for Aggregates and its BSI mirror committee. His professional career began with work on
the alkali–silica reactivity of aggregates, progressed through measuring and controlling
swelling clays in sands, the thaumasite form of sulphate attack, the increased use of recycled
and secondary aggregates, and innovative asphalt mixtures and asphalt/cementitious com-
posites. His current interests include the effects of alternative fuels and alternative raw mate-
rials in cement manufacture, alkali-activated cements, and the development of lower carbon
multi-component cements.
Robert Lewis was the Technical Marketing Manager at Elkem Silicon Materials. He began
his career as a field technician in 1978 for Tarmac Topmix, Southern Region in the UK. He
immediately took on the City and Guilds courses in Concrete Practice and Technology,
passing them with distinction and credit.
In 1986 he moved to Elkem Materials, joining the technical services of concrete oper-
ations in the UK, eventually becoming the Technical Marketing Manager. In 1999 he was
made a Fellow of the Concrete Society, in 2013 a Fellow of the American Concrete Institute
and in 2017 a Fellow of the Institute of Concrete Technology. In 2017 he was elected to
Chair the British Standards Committee B/517/4 dealing with Pozzolans and it was also
in that year he was elected as Vice President of the Institute of Concrete Technology and
will take over the Presidency in 2019.
In August 2018 he joined Ferroglobe PLC as the Technical Marketing Manager for Silica
Fume for the European and International (non-US) regions. He is the UK expert to the CEN
(European Standards) committee for Silica Fume, and has written, co-authored and pre-
sented numerous papers on microsilica and its use in concrete.
He is currently on 9 committees of the American Concrete Institute, including the Inter-
national Advisory Committee, dealing with Cementitious Grouting and Fire Resistance, and
is currently the Chair of ACI committee 234 ‘Silica Fume’.
Author Biographies xxv

Donald E. Macphee is a Professor of Chemistry at the University of Aberdeen. His interest
in cement chemistry, and in phase diagrams, began when he joined Professor FP Glasser’s
group in 1984. He later took up a position at CSIRO in Australia in 1989, where he led the
Cement and Concrete Technology Group at the Division of Building, Construction and
Engineering, gaining experience in the application of cement chemistry in concrete tech-
nology, before returning to a faculty position at Aberdeen in 1992. He research on cementi-
teous systems has included phase equilibria studies, novel binders, processing and non-
destructive characterisation methodologies, and more recently, cements and concretes as
photocatalyst supports. He has published over 100 journal and conference papers, is a
member of the editorial boards of Cement and Concrete Research and Materiales de Con-
strucción and he is a Fellow of the Royal Society of Chemistry (CChem FRSC).
Michael J. McCarthy is Reader in Civil Engineering in the School of Science and Engi-
neering at the University of Dundee, Scotland, UK, where he also obtained his bachelor and
doctoral degrees. He has carried out research on a range of topics in the cement and concrete
materials, and construction technology areas over the past 25 years. Much of this has
addressed practical issues and has been in collaboration with industry. His work on fly
ash in concrete has included the use of material, (i) covering a range of properties to EN
450-1, (ii) following wet storage in stockpiles and lagoons, including processing, (iii) in
ternary blends for optimum durability performance, (iv) at high volumes in cement and
(v) produced from modern power stations, e.g., using co-combustion or supercritical tech-
nology. He has also investigated fly ash in cementitious grouts and in lime stabilisation of
soil, for reducing expansive effects caused by sulfate. He has given several invited lectures
on his research and is the author of more than 100 publications.
Sidney Mindess is an Emeritus Professor in the Department of Civil Engineering, Uni-
versity of British Columbia, Vancouver, Canada, where he taught from 1969 till his
retirement in 2005. He is the author or co-author of more than 300 publications on civil engi-
neering materials, primarily dealing with cement and concrete. He is a fellow of the
American Ceramic Society, the Canadian Society for Civil Engineering, the American Con-
crete Institute, and RILEM. He has lectured on cement and concrete worldwide, and was at
various times a Marine Technology Visiting Fellow at Imperial College, United Kingdom,
and a Lady Davis Fellow at the Technion, Israel. He was also one of the original researchers
in the Canadian Network of Centres of Excellence dealing with high performance concrete.
His current research interests include fibre reinforced concrete, durability of concrete, sus-
tainability of cement and concrete, and service life prediction.
xxvi Author Biographies

Micheline Moranville-Regourd is Honorary Professor of the Ecole Normale Sup
erieure de
Cachcan, and formerly a researcher in the Thematic Unit Microstructure and Durability of
Building Materials at the Laboratory of Mechanics and Technology of the ENS. She has also
been Associate Professor at the University of Sherbrooke, Quebec, Canada.
After her doctoral thesis in the physical sciences, prepared at the Solid-State Physics
Laboratory at the University of Orsay, she pursued, in this same laboratory, the study of
the crystalline structure, the polymorphism and the solid solutions of silicates and silicates.
Calcium aluminates of Portland cement. Head of the Microstructures Department of the
CERILH (Center of Study and Research of the Hydraulic Binders Industry) and Master
of Conferences at the National School of Bridges and Chaussees, she turned to the study
of hydration mechanisms cementitious materials and their alteration in aggressive
environments.
She has been sought out in many areas of expertise in France and abroad. At the ENS de
Cachan, she directed during the last decade doctoral theses combining physics, mechanics,
thermics and chemistry, modelling and validating the multi-scale behaviour of building
materials in different aggressive environments.
Kevin A. Paine graduated with a PhD in civil engineering from the University of Not-
tingham in 1998 for his work on prestressed fibre reinforced concrete. He joined the Con-
crete Technology Unit at the University of Dundee as a Research/Teaching Fellow (later
promoted to Lecturer) where he published widely on the use of industrial by-products
and recycled materials as cements and aggregates. In 2007 he was appointed Senior Lecturer
(translated to Reader in 2015) within the BRE Centre for Innovative Construction Materials
at the University of Bath. His most recent research has concentrated on development of
nanotechnologically enhanced cements and self-healing and self-sensing concretes. He sits
on a number of RILEM technical committees and is an editorial board member for the Insti-
tution of Civil Engineers’ Construction Materials journal. He has published, lectured and
examined on cement science and concrete technology around the world.
John Lloyd Provis completed Bachelors degrees in Applied Mathematics and Chemical
Engineering at the University of Melbourne (Australia), in 2002, and a PhD from the same
university in 2006. He joined the University of Sheffield (United Kingdom) in 2012 as Pro-
fessor of Cement Materials Science and Engineering, and since 2016 has also been Head of
the Sheffield Engineering Graduate School. He was awarded the 2013 RILEM Robert
L’Hermite Medal for his work on geopolymers and alkali-activated cements, and in
2015 was presented with an honorary doctorate by Hasselt University, Belgium. He is Chair
of RILEM Technical Committee 247-DTA and a member of the RILEM Technical Activ-
ities Committee, a Fellow of the Institute of Materials, Minerals and Mining (IoM3), a
Voting Member of committees of ASTM and ACI, and Associate Editor of the journals
Cement and Concrete Research, Materials and Structures and Advances in Cement
Research.
Author Biographies xxvii

Karen Louise Scrivener obtained her PhD at Imperial College in 1984. She worked for
Lafarge in France for 6 years, before being appointed as a Professor and Head of the Lab-
oratory of Construction Materials, at EPFL, Switzerland in 2001. Her research focusses on
understanding the chemistry and microstructure of cement-based materials and improving
their sustainability. She is editor-in-chief of the leading academic journal Cement and Con-
crete Research and was made a fellow of the Royal Academy of Engineering in 2014.
Ian Sims is a Director of RSK Environment Ltd. in the United Kingdom, where he is respon-
sible for Materials Consultancy and Expert Witness Services. He graduated in geology at
Queen Mary College (London University) in 1972 and then undertook doctoral research
in concrete technology, including AAR in the British Isles, and his PhD was awarded in
1977. Ian joined Sandberg LLP in London in 1975 and gained wide experience with con-
struction geomaterials. In 1996, he moved to STATS Limited, which joined RSK Group
PLC in 2008. He has specialised for over 40years in concrete, its constituents and all aspects
of AAR. Between 1988 and 2014, Ian was Secretary of the RILEM Technical Committees
on AAR, when he was awarded RILEM Fellowship. As a Fellow of the Geological Society,
he was Secretary for four sequential Engineering Group working parties, producing report-
books on Aggregates, Stone and Clay materials and construction in Hot Deserts, also being
an editor for the current edition of Aggregates and for Clays; Ian received the Society’s
Engineering Group Award and later the Coke Medal. He has served on many other com-
mittees, including chairing the editorial panel for ICE’s journal Construction Materials
and currently chairing the British Standards committee on Aggregates. Ian’s book publica-
tions include Concrete Petrography: A Handbook of Investigative Techniques, and Alkali-
Aggregate Reaction in Concrete: A World Review, both now in their second editions.
Peter del Strother graduated from the University of Bristol in 1971 with a BSc in
mechanical engineering. After experience in steam turbine commissioning and plant opti-
misation in large scale industrial food processing he joined ICI in 1979 as a construction
engineer. In the mid 1980s he was appointed manager of a wet process kiln and two rotary
lime kilns at Buxton, Derbyshire. In 1989 he joined Castle Cement as General Manager of
their one million ton per annum Clitheroe works. In 1997 he became Technical General
Manager for the three Castle Cement works, which now belong to the Heidelberg Group
of companies and trade as Hanson Cement. In this position he focused on troubleshooting
and plant optimisation on wet, long dry, preheater and precalciner kilns and was responsible
for process and combustion aspects of the introduction of a range of alternative fuels. Circa
2000 he carried out geological and chemical assessment for a major quarry extension. Inde-
pendently from his employer he undertook a geology degree by research, for which he was
awarded an MPhil at the University of Manchester. In a ‘hands on’ process engineering role
he has worked on all stages of the cement production process from quarry chemistry control
to cement milling, including the impact of the process on emissions to atmosphere. He intro-
duced the routine use of mass and heat balances and through increased understanding of
volatile cycles markedly improved kiln run factors. In the 2000s he was responsible for
the conceptual design of a 2600 te/day PC kiln, designed to maximise use of waste-derived
fuels, and as commissioning manager saw the project through to completion. After retiring
he set up a cement consultancy company, PJDS Consulting Ltd. He has carried out week
long audits in cement works in Africa and Europe. He has also carried out training seminars
on subjects from cement chemistry to kiln operation.
xxviii Author Biographies

Bruno Touzo has a doctorate degree in materials science from the University of Orleans,
France. After a post-doctoral position in the University of Aberdeen, Scotland working on
cements and clinkers, he joined the Lafarge Research Centre in the Aluminates Cement
Division. He later joined Kerneos (now part of Imerys) in research, development and pro-
duction. He is currently manager of the Imerys Technical Centre in Tianjin, China.
His main topics are linked to high temperature materials, such as the design of new
cements, clinkers and refractories.
Edwin A.R. Trout is a librarian by profession, he joined the British Cement Association in
1995 to manage its specialist library, originally established in 1937. In 2006 Edwin trans-
ferred, with the ownership of the library, to The Concrete Society for whom he now works.
He is also Secretary of the Cement Industry Suppliers’ Form and Executive Officer of the
Institute of Concrete Technology. Over the years Edwin has developed in interest in early
concrete construction and the history of the cement industry, and has written articles for
several technical or historical periodicals, including three papers for Construction History
Journal. He won a prize for a research paper on early cement mills and his book, Some
writers on concrete, was published by Whittles in 2013. He is currently member of the
fib Task Group: History of Concrete Structures.
Alexander Wilson is a geologist and Principal Engineer who worked for Schlumberger
Oilfield Services for 29 years. He is a Chartered Energy Engineer. Prior to joining Schlum-
berger in 1987 he worked for Gearhart Geodata Services for 5 years as a Wellsite Geologist
and Petrophysicist. He has extensive expertise in the research and development of oilfield
chemical products, including well cements and fracturing fluids.
Author Biographies xxix

Foreword
Producing the fifth edition of a book that first appeared over three-quarters of a century ago is a brave undertaking. Inevitably
the subject will have moved on, but how much of the appeal of the original—and of its subsequent revisions—might be lost
with the changes? To what extent should changes in style and even the opportunities provided by new methods of book pro-
duction be embraced, are the fundamentals just as relevant; perhaps they need a more modern interpretation?
The editors for this fifth edition—Peter Hewlett and Martin Liska, both well-known names in the subject area with
decades of experience gained mostly working in the Industry on both in-house RD and on making research advances from
many sources more accessible to practitioners, and their team of 30 authors drawn from 4 continents—have certainly been
assiduous in their task. To take one simple indicator: the average number of references listed at the ends of the 17 chapters is
over 200, with the largest being 581 and the total 3540.
Despite assertions that ‘the younger generation only uses “on line”’ or that ‘Google is now our primary source’, there is
something comforting about actually having the material in one’s hand, being able to browse freely and knowing that within
those book covers resides much of what we may need to consult over the coming years. Also that it has been lovingly
assembled, carefully evaluated and presented in a form designed to make the substance accessible, the advice clear and
its pedigree available. Thus a revision of an ‘old friend’ provides the experienced with the chance to gain access to a more
up-to-date version of their favourite repository of information, knowledge and guidance; for those coming new to the book at
this stage it proves the value of accumulated scholarship and wisdom distilled into an accessible form.
Because my background has, very largely, been in steel construction, unlike the author of the Foreword to the previous
edition, George Somerville—someone I had known and respected for almost 50years—I am not qualified to pronounce on the
technical changes, the new topics selected for inclusion or even the decision that some earlier material no longer merits
retention. But I do know something about books of this type from my own field, where ‘The Steel Designers’ Manual’, first
produced in 1952 by a group of four authors similarly employed in the business of making the latest technical advances more
accessible to practitioners, is now in its seventh edition, with the decision to move to a multiauthor format having been taken
with the fifth edition. It, too, has long been regarded as the first place to look for guidance, with well-thumbed copies being a
staple feature on the shelves of every office, and of a considerable number of individuals with an interest in the subject.
I have no doubt that the fifth edition of Lea’s will be welcomed by those already wedded to its predecessors, will be a
pleasant surprise to those coming to the book for the first time and will be just as treasured as its ancestors.
Professor D.A. Nethercot
OBE, FREng, FTSE, NAE, Emeritus Professor of Civil Engineering
Imperial College London, United Kingdom
xxxi

Preface
The first edition of this book represented the dedicated work of both F.M. Lea and C.H. Desch and up to the third edition that
of Lea. In that regard the first edition cannot be emulated. The technical width, depth and rigour of the first three editions stand
as testimony to those authors. The fourth edition and now the fifth edition of F.M. Lea’s book is intended to follow the
tradition of the previous four. The other editions were noted reference works being a combination of knowledge based
fundamental understanding and the pragmatic application of such knowledge relating to cements and concretes, their devel-
opment and responsible exploitation.
One of the problems in putting together a substantial book such as this is that it takes a considerable time to compile.
During that time technical issues move on and we were very aware of maintaining the book’s currency up to publication.
However, the book is a reference work and hopefully assists users to appreciate both what went before and yet provides
a platform from which technical projections can be made underwriting progress in both cement and concrete development
and usage.
We were very conscious that the previous edition 4 comprising 16 chapters and 19 contributors, some of whom have
regretfully passed away, was beyond our individual capability in producing this edition. As a consequence we have called
upon others to address particular topics and aspects. This fifth edition has some 17 chapters and 32 contributors enhancing the
range of widely differing issues about cements and concretes.
First published in 1935 by Lea and Desch the book has evolved with previous edition 4 being a substantial restructuring of
the book.
Edition 5 is more of a combination of revision and rewrite. We were very aware of the substantial previous work for
edition 4 and wish to acknowledge the input of the then chapter authors who are not included in this edition. These are Robert
G. Blezard, Bev Brown, Alain Capmas, Margi Eglinton, Fredrik P. Glasser, Peter J. Jackson, Eric E. Lachowski, C. David
Lawrence, Franco Massazza and Ivan Odler. It is due to their previous contributions that gave the root to the present edition
and we wish to acknowledge that.
As such the book is an in depth compendium of scientific and technological information focussed on specific aspects of
cements and concretes. As with all materials development, application and usage engineering compromise is better achieved
when supported by good science.
The fourth edition was published in 1998 and reprinted in 2001. Over the last 20years there have been many changes
covering concreting materials, manufacture and use as well as research resulting in fundamental and practical understanding.
The aim of edition 5 is to present these changes and update the knowledge that exists.
Edition 5 has two new additional chapters, namely chapters 16 and 17 entitled ‘Geopolymers and Other Alkali-Activated
Materials’ and ‘The Influence of the Water:Cement Ratio on the Sustainability of Concrete’. The former is not a new topic but
the interest in and the application of these types of materials is increasing due to environmental, sustainability and enhanced
performance concerns that have growing relevance and acceptance.
Chapter 5 in edition 4 entitled ‘The Burning of Portland Cement’ has, in principle, been incorporated into Chapters 2 and 4
of the current edition.
The main purpose of the book remains unchanged dealing with the chemistry, physics and materials science of cements
and concretes and coupling that information with both manufacture and application.
The reality is that cements, concretes and their components are global and to this day concrete is by far the most widely
used construction material. Cements and concretes are adaptable but complex. Understanding this complexity and presenting
it in a manner that assists technological development and advancement is the purpose of this book.
Cements and concrete over the last 83years since the first edition was published have changed hugely. Such changes can
create uncertainty. To imbue confidence depends on understanding the fundamental materials science issues governing com-
position, manufacture and application. It is hoped that edition 5 engenders such confidence.
This edition, as did edition 4 opens with a chapter, newly authored, on the history of calcareous cements. It is presented in
some detail both textually and visually recording the origins and evolvement of cements.
xxxiii

Chapter 2 deals with ‘The Manufacture of Portland cement’. It has been newly authored covering revisions and updating.
Likewise for Chapters 3 and 4.
Issues dealt with Chapter 5 of edition 4 have been incorporated into current Chapter 4.
We have indicated in parentheses the chapter numbers in edition 4 where appropriate for those wishing to compare the
present edition with that previously.
Current Chapters 5 (6), 6(7) and 7 (8) have all been newly authored.
Current Chapter 8 (9) has been rewritten and re-authored presenting a current statement concerning low energy cements.
Chapters 9 (10), 10 (11) and 11 (12) have been updated but retain the style and content of edition 4 chapters with
considerable new material in Chapter 9 (10).
Chapter 12 (13) includes three new authors and deals with calcium aluminate cements and has been expanded incorpo-
rating applications as well as updated technical detail.
Chapter 13 (14) includes two new co-authors and incorporates magnesium oxide based cements.
Chapter 14 (15) also has an additional co-author and has been substantially expanded covering recent changes in admix-
tures, particularly the newer superplasticisers.
Chapter 15 (16) has two additional co-authors and new material.
Chapter 16 is a new chapter and has a new author reflecting current trends and interest in geopolymers and alkali
activation. The energy, sustainability and performance agendas will have to consider these new materials and their various
combinations along with other chemically based options.
Chapter 17 is also a new chapter and author dealing with the critical role of water in concrete. Most of concretes attributes
and limitations depend upon water addition, retention, interaction and removal. These matters are dealt with.
As with the fourth edition it has taken some while to produce edition 5. We hope the style and intent and standard of Lea’s
book has been maintained.
Concrete is and will continue to respond to the needs of the living world and no doubt a sixth edition will emerge as
required. A maintained legacy to Lea that we hope he would be proud of. As concrete evolves so will Lea’s book.
A book such as this requires sustained commitment and I (Peter Hewlett) wish to acknowledge the contribution of my
colleague Dr. Martin Liska both as co-editor and chapter author for his tireless and committed contribution to this work.
We also wish to acknowledge and thank all the authors of chapters that have contributed to this book. Their contribution
cannot be over-estimated and we as editors are indebted to them. We also wish to acknowledge those that have given advice,
encouragement and occasional criticism. These people know who they are and we thank them sincerely.
This type of book is a referenced and indexed work and as such is likely to be used when looking for particular information
and therefore, perhaps, only occasionally. Using the references and indexes widens the scope of enquiry and provides further
detail against particular topics. To aid the search for information the book has both author and subject indexes. As a
consequence the reader/user of this book will, it is hoped, appreciate the individual subject disciplines and their linkage
to cement and concrete. Nature disregards our artificial divisions of convenience but they do help us to understand and gives
structure to enquiry.
The users of this book are likely to be researchers, teachers, lecturers, students, consultants, designer/specifying practising
engineers and perhaps, on occasions lawyers.
Edition 4 was well received and it is gratifying to find copies around the world on people’s desks, in libraries, laboratories
and production plants as well as the offices of architects, civil engineers and the lockers of students. It is our hope edition 5
will be equally welcomed and used.
Finally we wish to dedicate this work to all who have an interest in and association with these remarkable materials we
simply call cement and concrete.
Professor Peter Clive Hewlett
Dr. Martin Liska
xxxiv Preface

International Cement Congresses
1918 First International Symposium on the Chemistry of Cement, London, January 1918. Published in: The setting of
cements and plasters – a general discussion. Transactions of the Faraday Society (London, 1918): 14: 1–69.
1938 Second International Symposium on the Chemistry of Cement, Stockholm, 1938. Published by
Ingeni€
orsvetenskapsakademien, Stockholm, 1938.
1952 Third International Symposium on the Chemistry of Cement, London, 1952. Published by the Cement and Concrete
Association, London, 1954.
1960 Fourth International Symposium on the Chemistry of Cement, Washington, 1960. Published by the National Bureau
of Standards, Monograph 43, US Government Printing Office, Washington DC, 1962.
1968 Fifth International Symposium on the Chemistry of Cement, Tokyo, 1968. Published by the Cement Association of
Japan, Tokyo, 1969.
1974 Sixth International Symposium on the Chemistry of Cement, Moscow, 1974. Published by Stroyizdat, Moscow,
1976.
1980 Seventh International Symposium on the Chemistry of Cement, Paris, 1980. Published by Editions Septima, Paris,
1980.
1986 Eighth International Symposium on the Chemistry of Cement, Rio de Janeiro, 1986. Published by FINEP, Rio de
Janeiro, 1986.
1992 Ninth International Symposium on the Chemistry of Cement, New Delhi, 1992. Published by the National Council
for Cement and Building Materials, New Delhi, 1992.
1997 Tenth International Symposium on the Chemistry of Cement, Gothenburg, 1997. Published by Amarkai AB and
Congrex G€
oteborg AB, G€
oteborg, 1997.
2003 Eleventh International Symposium on the Chemistry of Cement, Durban, 2003. Published by the Cement and
Concrete Institute, 2003.
2007 Twelfth International Symposium on the Chemistry of Cement, Montreal, 2007. Published by the Cement
Association of Canada, 2007.
2011 Thirteenth International Symposium on the Chemistry of Cement, Madrid, 2011. Published by Instituto de Ciencias
de la Construccion ‘Eduardo Torroja’, 2011.
2015 Fourteenth International Symposium on the Chemistry of Cement, Beijing, 2015. Published by China Building
Materials Press [in press].
xxxv

Abbreviated Formulae
The following abbreviated formulae are used in the text:
C ¼ CaO, A ¼ Al2O3, S ¼ SiO2, F ¼ Fe2O3, T ¼ TiO2
M ¼ MgO, K ¼ K2O, N ¼ Na2O, H ¼ H2O, S ¼ SO3, c ¼ CO2
Thus, for example:
C3S ¼ 3CaO . SiO2 C2F ¼ 2CaO . Fe2O3
C2S ¼ 2CaO . SiO2 C4AF ¼ 4CaO . Al2O3 . Fe2O3
C3A ¼ 3CaO . Al2O3 C3MS2 ¼ 3CaO . MgO . 2SiO2
CA ¼ CaO . Al2O3 KC23S12 ¼ K2O . 23CaO . 12SiO2
C2AS ¼ 2CaO . Al2O3 . SiO2 NC8A3 ¼ Na2O . 8CaO . 3Al2O3
xxxvii

1
The History of Calcareous Cements
Edwin A.R. Trout
‘Cements may be defined as adhesive substances capable of uniting fragments or masses of solid matter to a compact whole.
Such a definition embraces a large number of very different substances having little in common with one another but their
adhesiveness’ and these very differences have ‘tended to bring about a restriction of the designation to one group of adhesive
substances, namely, to the plastic materials employed to produce adhesion between stones, bricks c in the construction of
buildings and engineering works’. As these contain ‘compounds of lime as their principal constituents … the term ‘cements’
in this restricted sense then becomes equivalent to ‘calcareous cements’’.
That, in excerpt, is how Cecil H. Desch described the scope of the first edition of this book, written jointly with Sir Fred-
erick Lea in 1935, but with the opening pages drawn verbatim from his earlier book of 1911.1
After the passage of more than a
century, this expresses the topic succinctly enough, and excludes from present consideration—which concentrates on cal-
careous cements, a term first published by Higgins2
in 1780—a multitude of organic, bitumen- or oil-based materials with
which the development of building materials has long been entwined.
1.1 PREHISTORY
Lime occurs in many natural forms and for several millennia different chalks and limestones have been burnt to make a range
of building materials that harness their cementing qualities. In modern usage, however, we should distinguish between pure
and hydraulic ‘limes’ and gypsum-based plasters and the stronger, harder ‘cements’ that contain a greater proportion of
siliceous materials. But until the time of the Industrial Revolution, such a distinction would not have been made.
Numerous authors have mined prehistory for precedents in the use of cementitious binders. Their inclusion depends upon
an accommodating definition of ‘cement’, but the following are ancient examples of the practical exploitation of cementitious
reactions: the religious structure at Gobekli Tepe in Anatolia, erected 12,000–10,000BCE, in which pillars are set in a ter-
razzo floor of burnt limestone and clay; and the city of Catal Hayuk, 9000BCE, where gypsum plaster was used as the base for
decorative frescos. Then at Yiftah’el in Galilee, a double-layered concrete floor of 30–60mm was discovered in 1985 that
dated from 7000BCE. The binder was quicklime, made from burning limestone in wood-fired kilns at temperatures of
850°C–900°C, and mixed with stone and water: evidence of an advanced production process from quarrying and crushing
to kiln construction and temperature management. Chemical analysis indicated a composition of calcium carbonate and a
small quantity of silica, and physical test results from cube samples returned strengths of 34MPa in the lower layer and
45MPa for the upper.3
A 250mm thick floor at Lepenski Vir, in Serbia, was cited for many years as the earliest known concrete.4
There the sand
and gravel was bound with a red limestone calcined to make quicklime. Quicklime was also used as stucco for the protection
of walls in Minoan Crete, around 2000BCE.5
Production of cementitious materials in ancient Egypt commenced perhaps as early as the fourth millennium BCE, when
mortar was used as bedding for masonry. Limestone was abundant in the Nile valley, but the fuel to achieve temperatures of
850°C–1000°C required to burn it, was not. So largely for that reason the ancient Egyptians used impure gypsum (CaSO4),
which formed a hemi-hydrate when burned at the lower temperatures that could be achieved easily with small fires at about
170°C. The earliest Egyptian cements then were essentially gypsum plasters. Plasters and cements based upon gypsum would
have had adequate strength, but, because they would have been soluble in water, limited durability. In the arid climate of
Egypt, however, this was not a disadvantage in practice and cements of this kind were used successfully until the Roman
period.6
According to the controversial contention advanced by Dr. Joseph Davidovits in the 1980s, one possible application of the
Egyptian mastery of low-heat cements was the casting in situ of a ‘geopolymeric limestone concrete’7
for the construction of
the Great Pyramids at Giza, rather than the placing of quarried natural stone. Such technology would depend upon a catalyst
triggering the inherent chemistry to form an artificial stone, much like the Egyptian development of synthetic sandstone
known as faience. Whatever the final conclusion of that debate, and whatever binders they used, it seems certain that the
Egyptians prepared and made use of concrete by at least 1950BCE, when the production process was illustrated on a panel
in Thebes, as reproduced in Fig. 1.1.8
Lea’s Chemistry of Cement and Concrete. https://doi.org/10.1016/B978-0-08-100773-0.00001-0
© 2019 Elsevier Ltd. All rights reserved. 1

To the east of Egypt, beyond Sinai, lay the desert kingdom of Nabataea—in the arid region to the south of Judea, around
the city of Petra in modern Jordan. Here the Nabataeans developed a system of subterranean cisterns to capture and store
water, which they proofed with a cementitious lining. Ancient fire pits have been discovered in modern times that contain
evidence of limestone calcination, suggesting a conscious effort to produce a calcareous mortar.9
1.2 THE CLASSICAL WORLD
It is to the Greeks of their golden age, however, that we owe a technological leap forward. The first use of a natural pozzolan
appears to date from about 500BCE. Lime mortars used in the southern Aegean were enhanced by the inclusion of volcanic
tuff from the island of Thera (now known as Santorini), to produce a material with greatly improved water resistances and
durability. An ancient cistern in Kamiros on the island of Rhodes illustrates the successful use of this material, combining
lime with ‘Santorin earth’ and fine sand in a ratio by volume of 6:2:1. Indeed Santorin earth has continued to be used in the
modern world, in combination with Portland cement or lime. Of its use in major structures that in the Suez Canal is perhaps
the best known example.10
As with much of their culture, the Romans borrowed heavily from the Greeks, and it is the use of volcanic ash that is
perhaps most distinctive of Roman binders. Indeed the very word ‘pozzolana’ derives from the Roman place name,
Puteoli—or Pozzuoli in Italian—in the district of Vesuvius, whence the ash was obtained.
There is a species of sand which naturally, possesses extraordinary qualities. It is found under Baiae and the territory in the neigh-
bourhood of Mount Vesuvius; if mixed with lime and rubble, it hardens as well under water as in ordinary buildings.11
The earliest major building thought to use pozzolana was the theatre at Pompeii, at the heart of this district, dating
from 75BCE.12
Pozzolana was a red or purple volcanic tuff found in locations around the Bay of Naples and the name
has since been extended to an entire class of materials that shares its mineralogical characteristics. One such is the
Rhenish tuff known as ‘trass’ that was found originally on Rome’s imperial border, yet continues to be used to the
present day.
The use of pozzolana was advocated by a Roman writer, Marcus Vitruvius Pollio (known to us now simply as
Vitruvius), whose De Architectura was written in 25BCE. He expanded on the theme of cement and its use in con-
struction, proposing alternative raw materials too and describing their use. If pozzolana were not available, Roman
builders might add brick or tile dust to the lime to achieve similar effects: ‘if to river or sea sand, potsherds ground
and passed through a sieve, in the proportion of one-third part, be added, the mortar will be the better for use’.13
There
is evidence that such use occurred also in the Minoan civilisation in Crete and so may represent another borrowing from
Greek practice.
Recent studies have replicated the Roman recipe, heating limestone to form quicklime, and adding water and volcanic ash
in a ratio of three parts ash to one part lime. The mortar was then mixed with four-inch volcanic fragments to make concrete.
Investigation by X-ray revealed clusters of Stratlingite crystals that act like micro fibres in counteracting crack formation by
reinforcing the interfacial zones and enhancing durability.14
But it was not just in the combination of materials that the Romans excelled. Their methods and standards of workmanship
also were rigorously applied. Pliny the Elder in his Natural history (CE c.78), when describing a concrete composed of
FIG. 1.1 Panel from Thebes.
2 Lea’s Chemistry of Cement and Concrete

quicklime, sand and silex, or flint, recommended that ‘the floor and walls built of this material should all alike be beaten with
iron bars’.15
Indeed in the 18th century the Frenchman Rondelet examined Roman mortars and came to the conclusion that
their excellence depended on the thoroughness of mixing and extensive ramming during placement. Certainly remaining
Roman works often exhibit a remarkable degree of density in their material composition that such care in preparation would
explain. Sophisticated structures such as the famous Pantheon (CE 128—Fig. 1.2) with its 43m-diameter dome and the multi-
level aqueduct at Pont du Gare (CE 150) bear testimony to the Roman achievement.
Roman practice evolved over the succeeding centuries of Republic and Empire, and its essence has been recorded by more
than archaeological remains. Of all the varied output of Latin literature the De Architectura of Vitruvius, though its treatment
of cement is not extensive, was to carry the flame of construction technology through the Dark Ages that followed the fall of
Rome. A copy was retained in Charlemagne’s scriptorum and was the source of many of the later mediaeval copies that have
survived today.
1.3 THE MIDDLE AGES
The Roman legacy was variously maintained or swept aside in the realms that arose in western Europe during and after
the Migration Period. In Britannia the 400-year-old Romano–British civilisation was succeeded by a Germanic Anglo-
Saxon culture in which construction practices were overwhelmingly based on timber. Evidence of lime burning does
exist—implied, for instance, by an 8th century mortar mill found in Northamptonshire16
—but the quality of mortar
is thought to have declined because of low kiln temperatures (and consequentially incomplete burning), the absence
of pozzolanic additions, and poor mixing. As church builders turned to masonry in the century or so before the Conquest,
and stone built castles were introduced by the Normans, the demand for mortar increased and by the 12th century quality
had improved. What had almost become a lost art in the early mediaeval period experienced a revival in the high Middle
Ages, manifested in better standards of burning, grinding and sieving. In a reflection of this improvement lime is men-
tioned by Bartholomew Anglicus in his encyclopaedic compendium of 1240, entitled De Proprietatibus Rerun. In it an
entry reads: ‘Lyme … is a stone brent; by medlynge thereof with sonde and water sement is made’, though this middle
English translation of the original Latin did not appear until 1397.17
The commonly held confusion of the terms ‘cement’
FIG. 1.2 The Pantheon, Rome.
The History of Calcareous Cements 3

and ‘mortar’ is anticipated here; ‘sement’ is used for mortar, as was generally the case in early usage, though ‘mortar’
had already appeared in English by 1290.18
Mediaeval mortar was made from non-hydraulic lime that weathered easily on exposure, but in major buildings such as
castles and cathedrals, the elements were designed to act in compression and so the low bond strength of masonry mortar
was of minor consequence. Beside jointing, lime mortar was also used for hearting—the mortar-bound rubble core of walls,
filling the void between skins of dressed stone—as at Reading abbey, and for foundations, as at the 13th century Salisbury
cathedral.
After the 14th century excellent mortar is found, the sand generally washed to remove fine particles dirt or clay, and by
the 17th century pozzolanic trass (cited in documents of the day as ‘tarras’ or ‘tarrice’) was often added. In addition to
experience gained in practice, the example of Rome must be acknowledged for much of the improvements gained in
the early modern period. The Renaissance saw a revival in the understanding and appreciation of classical civilisation,
across the spectrum of culture and scholarship, and where the architecture of the ancients was applauded, so the associated
technology was sought.
A copy of De Architectura was rediscovered in 1414, by Poggio Barccioline at St Gallen abbey, and the first printed
edition was published in 1486 by Fra Giovanni Sulpitius. A scholarly edition, complete with woodcut illustrations, was pre-
pared in 1511 by the Franciscan monk, antiquary and member of the Freres du Pont, Fra Giovanni Giocondo,19
and the text
was translated successively into Italian (1520s), German (1528), French (1547), Spanish (1582) and eventually into
English (1692).
Architects such as Alberti (1404–72), de l’Orme (1515–70) and above all, Palladio (1508–1580)—whose I Quattro
libri dell’Architettura of 1570 had such influence on architecture in both Italy and England—all cited Vitruvius in their
writing.
Likewise, in a book of more practical utility, Joseph Moxon of Wakefield (1627–91) quoted Vitruvius in the plain English
of his Mechanick Exercises, or the Doctrine of Handy Works, 1685.20
Trass, supplied from the Rhineland through the
Netherlands to England, became an increasingly accepted addition to lime during the 17th century.
1.4 THE AUGUSTAN AGE
Trass was used in the 1660s for what was then the largest English engineering project to have been attempted: the mole at
Tangier, constructed between 1663 and 1683, following the city’s acquisition on Catherine of Braganza’s marriage to Charles
II. The project was directed by Sir Henry Shere. Shere was advised by, among others, Genoese engineers who recommended
and supplied pozzolana from Italian sources. Anticipating future investigations, he experimented with a series of mortar for-
mulations to determine the optimum mix for setting and hardening under water.
In England the restoration ushered in a new era of scientific experimentation and discovery, with parallels found in
the Enlightenment of 18th century France and all across Europe, and though far from the forefront of endeavour, the
improvement of binders and the search for hydraulic cements was not ignored. An early authority was Bernard Forest
de Belidor whose Science des ingenieurs of 1729 touched on mortar, and was followed by the four-volume Architecture
hydraulique in 1737–53. Although he promoted the use of trass, he also perpetuated the widely held error that the purer
the limestone the better the lime, with marble the apogee and chalk the nadir. In his later work he proposed a method of
placing foundations under water, as tried at the harbour of Toulon, using a mixture of 12 parts pozzolana or trass, 9 of
quicklime and 6 of sand. After slaking the quicklime, the constituents were mixed with seawater, and a combination of
pebbles and slag or cinders added. Having partially hardened the concrete was reworked and lowered into the sea in
crates. This use of pozzolana at Toulon was the subject of a later study published in 1778 by Barthelemy-Fauja de
Saint Fond.
Similar aims were attempted by George Semple in 1752, when reconstructing the foundations of Essex Bridge across the
Liffey. Here he filled a cofferdam with ‘small stones, grave, sharp clean sand and finely powdered lime, thrown in promis-
cuously so as to mix equally together’.21
(In the usage of the day, ‘promiscuously’ simply meant, ‘intimately mixed’.) But like
Bellidor, he accepted that the best limestone yielded the best lime.
The late 17th century, and then the reign of Queen Anne, saw a considerable increase in the use of brickwork for domestic
building, and an adaptation of earlier buildings to suit the classically inspired precepts of fashionable taste, with new wings,
porticos and facades. Not only was lime mortar being used for hydraulic engineering, but for increasingly for bricklaying and
as stucco, or render marked to look like dressed stone. Demand for the latter led to the development of a class of materials
known as oil cements, which may be thought of now as an ‘evolutionary dead end’: In his Sir Frederick Lea Memorial
Lecture, John Newman set out a list of patents, as reproduced in Table 1.1, that traces the ultimately doomed pursuit of such
cements (Tables 1.2–1.3).

Nonetheless, though the medium was oil, the purpose to which these cements were put acted as a stimulant to the later
Roman and Portland cements, as we shall see. The great leap forward in this period was the investigation into hydraulic lime
conducted by John Smeaton in the 1750s.
1.5 JOHN SMEATON, 1756
Smeaton was the first in England to undertake a scientific investigation into why certain limes would set under water and what
it was that moderated its rate of hardening. Commissioned to replace Rudyard’s wooden lighthouse on the Eddystone Rocks,
the second such structure there to have been destroyed by the elements, he commenced a series of experiments in 1756 to find
a suitable masonry mortar that would withstand the frequent drenching of this storm swept location off the south west coast
near Plymouth. It has been said of him that in doing so, ‘the results he arrived at were very remarkable not only for their
practical utility, but also as an illustration of the ease with which a very acute observer may stop short of the attainment
of a great truth’.22
Contradicting the contemporary belief that the hardest stones yield the best limes—‘Its acquisition of hardness under
water did not depend upon the hardness of the stone; in as much as chalk lime appeared to be as good as that burnt from
Plymouth marble’23
—he discovered that the best raw material for a ‘water lime’ was, in fact, impure limestone. Those
limes that did set underwater all contained a naturally occurring proportion of clay, varying between 6% and 20%: ‘The
fitness of lime for water-building depended on the amount and composition of clay impurity.’ Smeaton tested 300 lime-
stones and the best of these appeared to be Aberthaw Blue Lias, occurring on either side of the Bristol Channel and
typically containing 86.2% calcium carbonate and 11.2% clay. Added to this he found that the Roman practice of com-
bining pozzolana—in his case an unwanted consignment from Civita Veccia purchased from a merchant in Plymouth—
gave the best results for his purposes, though he also considered trass and ‘some ferruginous substance of a similar
nature’ as alternatives. He even tried burnt ironstone and forge scales. His preferred proportion of pozzolana to calcined
lime was 50:50.24
TABLE 1.1 Patents for Cements Granted in the 18th Centurya
Date Name Medium Possible Fillers
1737 Alexander Emerton Pail and oil Stone dust, powdered glass, sand
1765 Rev Dr. Daniel Wark Oil Stone dust, marble drift sand, clay, brick dust, brown sugar, lime, various calcareous earths
1772 Charles Rawlinson Linseed oil Whiting, sea-coal, brick dust, white and red lead
1773 John Liardet Drying oil Any absorbent matter, lead, sand, gravel
1776 John Liardet Oil Calcined and pulverised calcereous matter, white or red lead, sand, marble, mineral powder
1777 John Johnson Oil As above but with addition of serum of blood
a
Listed by Newman.17
TABLE 1.2 Analyses and Computed Compound Composition of Cementa
Analysis by % of Weight Compound Composition
Source Date CaO SiO2 Al2O3 Fe2O2 C3S C2S Total
English 1849–55 58.50 20.40 5.90 3.80 38 30 68
German 1865 59.00 24.10 7.30 2.80 4 66 70
English 1880 59.40 22.40 7.80 4.20 13 54 67
German 1880 60.80 22.10 5.90 3.00 36 35 71
English 1890 59.10 22.80 8.00 3.40 9 59 71
French 1890 60.70 23.20 7.20 2.80 18 53 71
German 1890 61.50 22.50 7.50 3.20 24 46 70
English 1905 60.20 22.30 7.10 4.10 22 47 69
American 1905 61.10 21.80 7.40 3.30 29 41 70
English 1925 62.30 21.50 7.00 2.80 39 32 71
English 1950 63.10 21.40 5.80 2.70 51 23 74
English 1960–3 64.77 21.60 5.65 2.57 51.6 23 74.6
a
Selected figures abstracted from Halstead 1961/2.6

This hydraulic combination was used to seal the 1493 interlocking granite blocks with which the Eddystone Lighthouse—
Fig. 1.3—was eventually completed in 1759, resisting the constant spray over the foundations. The construction was so suc-
cessful that the lighthouse stood in situ until its replacement by a larger structure in 1882—and relocation to Plymouth Hoe,
where it remains to this day—and Smeaton’s hydraulic lime mixture was specified for government contracts until as late as
1867 when Portland cement was finally substituted during the extension of the Chatham Dockyard.25
Having searched for a lime that would set under water Smeaton didn’t quite discover cement, but he did help point the way
for others to follow, and his findings—which he finally published in 1791—directly influenced the subsequent development
of both natural and artificial cements.
Until Smeaton’s Narrative was published in 1791, however, other investigators remained unaware of his conclusions.
Notable among these was ‘Bry’ (Bryan, sometimes rendered Brindley)26
Higgins, whose Experiments and observations made
with the view of improving the art of composing and applying calcareous cements and of preparing quick-lime was published
in 1780, just months after obtaining a patent for hydraulic cement-based stucco. His experiments, and they were extensive,
were to investigate the principles governing the ‘induration’ (or hardening) and strength of cements in order to produce a
mortar that was better than the Roman equivalent. He prepared mixtures from various sources of lime and sand, recording
their characteristics, and subjected the resulting specimens to a range of exposure conditions. The data thus obtained enabled
Higgins to comment on the choice of constituents and the optimum proportions when mixed. He also examined the effects of
organic admixtures such as ox blood and linseed oil, and additions including various types of ash. The specification he finally
patented was for a mixture of quartzitic sand with a binder that combined equal quantities of bone ash with a finely ground
lime that ‘heats the most in slaking and which slakes the most when watered’.27
Although Higgins appears to have been
unaware of Smeaton, he did cite other researchers of the day—including a Monsieur Loriot whose New discovery in the
art of building was published in 1774—and quoted from the classical source, Vitruvius.
Despite his experiments Higgins’s patented stucco proved unstable in practice, and the output of other investigators, such
as Perronet and Fourcroy de Ramecourt in France, remained ephemeral. Commercially successful cement finally came in
1796 with the patenting of ‘Roman cement’ by the Rev. James Parker.
1.6 JAMES PARKER’S DISCOVERY OF ROMAN CEMENT, 1796
In 1791, the year of Smeaton’s eventual publication, Parker was the leaseholder of a plot of land on the riverside at Northfleet,
and from 17 May, the patentee of a process of calcining chalk and limestone. In 1796, having been in business and Northfleet
FIG. 1.3 Smeaton’s Eddystone lighthouse.

and Lambeth during the intervening years, he took out another patent for ‘a certain cement or terras to be used in aquatic and
other buildings and stucco work’,28
a material we would now describe as a natural cement. An account of Parker’s discovery
was published retrospectively, describing it as ‘purely accidental’.
When on a visit to the Isle of Sheppey, he was strolling along under its high cliffs on the northern side and was struck with the singular
uniformity of character of the stones upon the beach and which were also observable sticking in the cliffs here and there. On the
beach, however, the accumulation of ages, they lay very thick. He took home with him two or three in his pocket and without any
precise object in view, threw one onto the parlour fire from which in the course of the day it rolled out thoroughly calcined. In the
evening he was pleased to recognise his old friend upon the hearth, and the result of some unpremeditated experiments with it has
been the introduction to this country of a strong, durable and valuable cement.29
Parker’s patent specifies the reduction to powder of ‘certain stones or argillaceous products called noddles of clay’.30
These, known today as septaria, he described in turn as ‘concretions of clay containing veins of calcareous matter …’,
traces of iron oxide giving the resulting cement a characteristically brown colour. Once ground the cement was mixed
in proportions of two measures of water to five of powder, the mixture setting within 10–20minutes, either in or out
of water.
In March and April 1796, just prior to the grant of patent on 28 June, the eminent engineer Thomas Telford tested the new
material and wrote to his client that he considered himself ‘fully justified in recommending to the Directors to use
Mr. Parker’s Composition, in place of Dutch Tarras, in constructing of the Pier at Lochbay in Skye’.31
Besides marine appli-
cations, Telford also proposed its use for cisterns, arches, flat roofs and, when mixed with lime, as stucco.
Bringing his new material to market, Parker named it ‘Roman cement’ in a promotional pamphlet headed Roman
cement, artificial terras and stucco, presumably for the hydraulic qualities which enabled it to take the place of the
pozzolanas currently available. Certainly the precedence of classical Rome was widely appreciated at the time, and pre-
vious investigations into cement production had cited the Romans’ example, such as Loriot’s Cement and artificial
stone: justly supposed to be that of the Greeks and Romans in 1774, and de la Faye’s Recherche sur la preparation
que les Romains donnoient a la chaux in 1787. However, despite Telford’s endorsement and the protection afforded
by his patent, Parker found business slow and he soon sold his rights to Samuel Wyatt, who traded henceforth as Parker
and Wyatt.
Septaria—the cement stones used as the raw material for Roman cement—were to be found around the British Isles,
particularly in the Thames estuary at Sheppey and Harwich, and off the Yorkshire coast. When Parker’s patent expired in
1810, a considerable industry built up in these and other locations, and Roman cement became the leading cement of the
first half of the 19th century. The first new entrant was James Frost at Harwich in 1807—government contracts protecting
him from prosecution for breach of patent—followed in 1810 by Messrs. Francis and White at Blackfriars, in 1811 by
James Grellier at Sheerness and William Atkinson at Sandsend, Yorkshire, and by Samuel Shepherd at Faversham in
1813. Sundry other companies were established in Kent, Essex and along the Thames during the 1820s, as well as on
the Humber, and in Derbyshire and Glasgow in the 1830s. Manufacture of Roman cement commenced in Somerset
and Staffordshire in the 1840s.32
Mr. J. Mitchell of Sheerness Dockyard conducted a series of experiments on the various sources of Harwich and
Sheppey septaria, the results of which were recorded by Pasley,33
but perhaps the best known demonstration of the qual-
ities of Roman cement was a test to destruction of an ‘Experimental Brick Beam’ erected for the Southampton Railway
near its London terminus in Vauxhall. This beam, built of brickwork, had an unsupported span of 21ft 4in. between
piers. Burdened with a suspended cradle loaded with pig iron, it bore nearly 11 t without deflection or cracks for almost
2 years. The Civil Engineer and Architect’s Journal described it as ‘a surprising proof of the strength of adhesion of
Roman cement’.34
Eventually, in February 1838, it was loaded as an experiment witnessed by the Council of the Insti-
tution of Civil Engineers and many Fellows of the Royal Society. It broke only when the suspended weight—illustrated
in Fig. 1.4—reached about 30¼ t.
Parker was not the only pioneer at the turn of the century, however, and nor was the British industry alone in
manufacturing cement. Developments in Britain had parallels in America and France too. In 1796 a French military engineer
named Lesage discovered the hydraulic properties of pebbles on the beach at Boulogne-sur-Mer and commenced production,
and across the Atlantic, in 1817, Canvas White found a natural cement rock in the state of New York. By 1818 natural cements
derived from argillaceous magnesian limestone were being produced at Rosendale in the United States and were used initially
for building the Erie Canal. An American industry developed and from an output of 300,000 barrels in its first decade, pro-
duction rose to an annual peak of 9,868,179 barrels in 1899.35
Likewise in Europe the manufacture of Roman cement was
gradually taken up during the century, especially in the German states, Switzerland and the diverse provinces of the Austro-
Hungarian Empire, as indicated in Fig. 1.5.

1.7 FRENCH INVESTIGATION, 1805–13
As Enlightenment gave way to Revolution in France, the Napoleonic Empire developed a legacy of scholarship and practical
experiment, given greater prominence by the exigencies of war and the requirements of naval and military engineering.
Among the most prominent investigators were the following36
:
1787. Jean Antoine Chaptal, chemist: experimented in making artificial pozzolana by calcining clays and schists found in
Languedoc, and tested at the harbour of Cette.
1805. M. Gratien le Pere, Engineer-in-chief at Cherbourg: experimented with calcined shale, especially of Haineville, to
replace the wartime shortage of pozzolana needed for works at the port of Cherbourg.
1807. J.B. Vitalis, Professor of Chemistry at Rouen: analysed hydraulic limestone near Rouen, discounting manganese
and proposing clay as the source of hydraulicity. Also experimented on local earths to convert to artificial pozzolana and
tested in the Seine.
1808. M. Daudin, engineer of roads and bridges, engaged on the Canal du Midi: investigated the properties of natural and
artificial pozzolanas, and proposed the use of calcined siliceous iron ore as a substitute for pozzolana (silica 50%, iron
oxide 31%, alumina 16% and manganese oxide 3%).
1807. M. Fleuret, Professor of Architecture at the Royal Military College at Paris: used tile dust or iron slag to supplement
the lime that he mixed with sand or ground stone when manufacturing artificial stone at his own factory.
1812. Jean Rondelet, architect: drawing heavily on Vitruvius, he described good practice in making and using mortar, and
offered the results of experiments into crushing strength and adhesion.
1813. Collet Descotils, Professor of Chemistry at the School of Mines: analysed Senoches limestone and found it con-
tained silica that, after calcinations, proved to be soluble in acids. He attributed its hydraulic properties to this combination
of soluble silica with lime.
FIG. 1.4 Experimental brick beam erected in front of Messrs. Francis and Sons Roman cement manufactory, Nine Elms, near Vauxhall Bridge.
(From the Civil Engineer and Architect’s Journal; Mar. 1838;1:135.)

This period of experimentation culminated in the work of Louis Joseph Vicat, the only one of his contemporaries whose name
is readily recalled today, continuing as it does in that of test apparatus and a modern manufacturing company.
1.8 LOUIS JOSEPH VICAT, 1812–18
Vicat trained as a civil engineer and in 1812, just a few years after graduating from the Ecole des Ponts et Chaussees, was
commissioned to build a bridge over the Dordogne at Souillac. The challenges of this site, however, acted as a catalyst for
his career defining experimentation with suitable materials with which to fulfil the project, and which he wrote up and
published in 1818 as Recherches experimentales sur les chaux de construction, les beton et les mortiers ordinaries, illus-
trated in Fig. 1.6.
This work tabulated the findings of his tests on 15 sources of lime, and later he set out the first systematic classification of
limes and hydraulic limes. Drawing on the data—and referring to the classical authors Vitruvius and Pliny, and the British
investigators Smeaton and Parker—he proposed a theory of the setting and hardening of lime mortars in water, even coining
the term ‘hydraulic’ (or ‘hydraulique’ in French).37
He applied his conclusions to the invention of an artificial hydraulic lime,
a calcined mix of powdered limestone and slaked lime with clay. He experimented with the grinding process and firing tem-
peratures, and established the optimum proportions of constituent materials. His specification was for limestone (43m3
),
slaked lime (34.55m3
) and clay (5.76m3
), ground in a wet mill and burnt for sixdays with 150 m3
of wood. Having reported
his preliminary findings in 1817, he demonstrated his hydraulic lime a year later to the French Academy of Sciences, which
approved its use unhindered by patents. His suggestion that hydraulic limes or cements could be produced artificially by firing
blends of chalk (or limestone) and clay was taken up by others—including Maurice St Leger at Meudon near Paris, and
FIG. 1.5 Location of the principal Roman cement plants in 19th century Europe (Weber128
).

James Frost and Colonel Pasley in England—and independently confirmed by the experiments of Johann Friedrich John
(1782–1847) of Berlin, a Professor of Chemistry, in his Uber Kalk und Mortel (1819).38
On the other hand, practical experiments undertaken during the repair of the French fortress at Strasbourg convinced Vicat’s
contemporary, General Treussart, that the ancient use of pozzolana in lime mortar was a preferable substitute for naturally
hydraulic limes than its artificial alternative. The pamphlet Treussart published in 1829 challenged opinions expressed by Vicat.
1.9 EARLY SPECIFICATIONS FOR ARTIFICIAL CEMENTS, 1811–30
Although the production of Roman cement expanded considerably after the expiry of Parker’s patent in 1810, there were
several early attempts to artificially replicate the naturally cementitious qualities of septaria. Edgar Dobbs of Southwark
was among the first in England, filing a patent in 1810 for a mixture of three parts of chalk, one part of clay and one of
ash ‘such as is sold by the dealers in breeze’,39
but his business was short-lived. James Frost, having commenced in Roman
cement, also turned to the manufactured product. Travelling to France he sought the advice of Vicat before bringing his exper-
iments to a conclusion with a patent dated 1822 for a material he named ‘British Cement’.
I select such limestones or marls or magnesian limestones or marls as are entirely or nearly free from any admixture of alumina or
argillaceous earth, and contain from 9% to 40%. of siliceous earth, or silica, or combinations of silica and oxide of iron, the silica
being in excess and in a finely divided state, and break such selected materials into small pieces, which are then calcined in a kiln …
until all carbonic acid be expelled, and … the calcined material is to be ground to a fine powder ….40
Frost ground his materials according to local practice, rather than Vicat’s preferred method, though he adopted the
Frenchman’s use of the wash mill. He set up a works in 1825 at Swanscombe, on the Thames in Kent, from which he intro-
duced his product to the market. It was first used at Hungerford Market, for foundations and stucco. British Cement was
FIG. 1.6 Vicat and the first edition of his Recherches Experimentales, 1818.

lightly calcined and sold at a cheaper price than Roman cement, having a ‘cohesive strength’ of about two thirds when tested
in 1837.41
Its quality relative to other cements may be gauged by the following tensile strengths at 11days: Frost’s British
cement (17.6 lbs./in.2
); Francis’s Roman cement (30.6 lbs./in.2
)—and Pasley’s (see below) (34.9 lbs./in.2
).42
Experimenting with artificial cements shortly after Frost commenced production was Lt. Col. Charles (later Gen.
Sir Charles) William Pasley, the officer commanding the Royal Engineers’ establishment at Chatham from its foun-
dation in 1812 and who is portrayed in Fig. 1.7. In 1826 he introduced a course in Practical Architecture and turned his
attention to the challenge of making an artificial Roman cement. He instigated an extensive series of experiments, and
visited Frost at Swanscombe in 1828 to compare materials and methods. Eventually he proposed a mixture of five parts
of chalk to two parts clay, specifying the blue clays of the Medway mudflats, and published his conclusions in 1830:
Observations, deduced from experiment, upon the natural water cements of England and on the artificial cements that
may be used as substitutes for them. He went on to write in much greater detail 8 years later and, by the time of its
second edition in 1847, his Observations on Limes, calcareous cements, etc. was the standard text on the subject in
English.
Another contemporary of Frost was William Lockwood. With Roman cement being used largely for stucco and archi-
tectural modelling, Lockwood—the proprietor of a building firm in Woodbridge, Suffolk, which in 1804 had become
agents for Parker and Wyatt’s Roman cement—was drawn to the idea of producing a stone-coloured cement by careful
selection of the sources of lime used. In 1817 he toured the country for appropriate limestone: to the East Midlands, to
Dorset, and to Bristol and South Wales. At some point between 1819 and 1822 Lockwood extended his operations to
premises in Spitalfields and, with James Pulham placed in charge, began the small-scale production of an experimental
stone-coloured cement for his firm’s own use. Swansea lime was considered to combine adequate quality with ease of
availability by sea. Joined by his son William Jr. in 1822, Lockwood set up in full-scale manufacture in Woodbridge,
using lime from Swansea and Barrow, and a windmill for grinding. Significantly, in view of Joseph Aspdin’s patent of
1824, Lockwood was already trading as a ‘Portland and Roman cement manufacturer’ in 1823, as attested by the trade
directories of that year.43
FIG. 1.7 General Sir Charles Pasley.

1.10 ASPDIN’S PATENT FOR PORTLAND CEMENT, 1824
Joseph Aspdin’s patent for Portland cement is the most famous of its kind by far, and the direct progenitor of the present
Portland cement manufacturing industry. It is reproduced here as Fig. 1.8. However its wording is obfuscatory, either by
oversight or design, as no useful information is supplied regarding the relative proportions of limestone and clay, the kiln
temperature, the duration of firing or the fineness of grinding.
I take a specific quantity of limestone such as that generally used for making and repairing roads, after it is reduced to a puddle or
powder; but if I cannot procure a sufficient quantity of the above from the roads, I obtain the limestone itself and I cause the puddle or
powder, or the limestone as the case may be, to be calcined. I then take a specific quantity of argillaceous earth or clay and mix them
in water to a state approaching impalpability, either by manual labour or machinery. After this proceeding I put the above mixture
into a slip pan for evaporation, either by the heat of the sun or by submitting it to the action of fire or steam conveyed in flues or pipes
under or near the pan, until the water is entirely evaporated. Then I break the said mixture into suitable lumps and calcine them in a
furnace similar to a limekiln till the carbonic acid is entirely expelled. The mixture so calcined is to be ground, beat or rolled to a fine
powder and is then in a fit state for making cement or artificial stone. This powder is to be mixed with a sufficient quantity of water to
bring it to the consistency of mortar and thus applied to the purposes wanted.44
Although the name ‘Portland cement’ is introduced—from its association with the qualities and prestige of the then fash-
ionable Portland stone which cement stuccos were designed to emulate; a comparison also made by Higgins in 1780 and
Smeaton in 1791—it is certain that the material specified was somewhat removed from the cements of today.
‘Nothing more than a hydraulic lime’, Blezard argued in the previous edition of this chapter: ‘its mineralogy was
completely different, as was its hydraulic activity.45
It offered ‘little evidence of CaO–SiO2 interaction’, he states
elsewhere,46
as the firing temperature was ‘too low for compound synthesis’. Nonetheless, Aspdin’s patent marks an essential
step in the development that led to the Portland cements of today. Aspdin’s gravestone of 1855 is clearly inscribed ‘Inventor
of the Patent Portland Cement’.47
Despite doubts as to the quality of Aspdin’s early binders, often expressed by historians of the industry, double burning the
limestone and the fine subdivision achieved by slaking during the intermediate stage would have represented an advance on
the light burning of wet-mixed chalk and clay such as Frost and others relied on.48
Aspdin is known to have used a kiln of glass
furnace design rather than the traditional limekiln.49
The importance of a thorough amalgamation of materials is recognised in
the specification of ‘a state approaching impalpability’.50
It is also without doubt that Aspdin and his sons produced cement
with commercial success for many years into the Portland era.
1.11 THE ‘PROTO-PORTLAND’ ERA, 1824–44
For the early years of production, in which it seems likely that kiln temperatures failed to reach the point of incipient fusion or
vitrification (i.e. around 1450°C, at which clinker forms), Blezard proposed the term ‘Proto-Portland’.51
This was a period in
FIG. 1.8 British patent No. 5022 (21 October 1824) granted to Joseph Aspdin.

which the technology, while constantly improving, had not achieved the characteristics we would recognise today as a true
Portland cement, regardless of the name under which it was marketed.
Aspdin was a bricklayer and builder from Leeds, whose experiments with cement from 1811 onward indicate a
familiarity with the work of fellow Yorkshireman John Smeaton, and his own contemporaries, Parker, Frost and
others. Indeed a copy of the 1813 edition of Smeaton remains with his descendants. Having registered his patent
on 21 October 1824, and a supplementary one the following year, Aspdin established a factory in Kirkgate,
Wakefield—depicted as Fig. 1.9—where he continued to manufacture until 1838. He resumed production at a nearby
site in 1839 and relocated to Ings Road in 1848. When the cement industry consultant and publicist Henry Reid
visited in 1870s, he considered the cement had been much improved during these 20years. However, there is little
evidence to adduce for this: Reid was writing years after the event, having visited replacement works, while the claim
by Joseph’s son William Aspdin that Brunel had employed Portland cement in repairing the Thames Tunnel in 1828
does not bear scrutiny.52
Blezard went on to characterise two further periods—those of Meso-Portland and Normal Portland cements—which we
will also consider below.
1.12 WILLIAM ASPDIN AND ‘MESO-PORTLAND’ CEMENTS
In July 1841 William left the family firm in Wakefield and made his way to the capital where by the summer of 1843 he had
become involved with cement manufacture in Rotherhithe at a works owned by J.M. Maude, Son Co. An announcement by
this firm made it clear that Portland cement was being introduced to the London market, its manufacture locally overcoming
the high cost of carriage from Yorkshire. But this same announcement indicated it was a new cement: ‘as a consequence of
improvements introduced in the manufacture … it is stronger in its cementive qualities, harder, more durable, and will take
more sand than any other cement now used’.53
Clinkering or over-burning had been found to improve strength, even if one
can only presume the discovery was accidental.
It was not long before this new Portland cement was investigated. In 1843 the contractors rebuilding the Houses of Par-
liament, Messrs. Grissell and Peto, undertook comparative tests. They summarised the results, illustrated in Fig. 1.10, in a
letter of 13 November, acknowledging ‘very satisfactory evidence of the superiority of your cement’.54
Mixed with three
parts sand, Portland cement was more than double the strength of Roman. Positive publicity and some influential advocacy
followed shortly afterwards, while the threat of shortages and taxation, and a building site disaster at Euston in 1848, under-
mined the previous dominance of Roman cement.
Responding to the evident potential of this improved ‘meso-Portland’, and ‘attracted by the flourish of trumpets, that was
then being made about the new cement’,55
the long-established Roman cement firm J.B. White and Sons turned to its man-
ufacture in 1844. The company’s works at Swanscombe were under the direction of Isaac Johnson who, having studied chem-
istry in his spare time, attempted to emulate the rival firm’s product. First seeking a chemical analysis of Maude and Aspdin’s
cement, he experimented with additions of bone ash, then with the mineral constituents of septaria respectively from Sheppey
FIG. 1.9 Joseph Aspdin’s first cement works at Kirkgate, Wakefield.

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