Repair, Rejuvenation and Enhancement of Concrete Proceedings of the International Seminar held at the University of Dundee, Scotland, UK on 5-6 September 2002 Edited by Ravindra K. Dhir Director, Concrete Technology Unit University of Dundee M. Roderick Jones Senior Lecturer, Concrete Technology Unit University of Dundee and Li Zheng Research/Teaching Fellow, Concrete Technology Unit University of Dundee "I1 Thomas Telford Published by Thomas Telford Publishing, Thomas Telford Ltd, 1 Heron Quay, London E14 4JD. www.thomastelford.com Distributors for Thomas Telford books are USA: ASCE Press, 1801 Alexander Bell Drive, Reston, VA 20191-4400, USA Japan: Maruzen Co. Ltd, Book Department, 3-10 Nihonbashi 2-chome, Chuo-ku, Tokyo 103 Australia: DA Books and Journals, 648 Whitehorse Road, Mitcham 3132, Victoria First published 2002 The full list of titles from the 2002 International Congress 'Challenges of Concrete Construction' and available from Thomas Telford is as follows • Innovations and developments in concrete materials and construction • Sustainable concrete construction • Concrete for extreme conditions • Composite materials in concrete construction • Concrete floors and slabs • Repair, rejuvenation and enhancement of concrete A catalogue record for this book is available from the British Library ISBN: 0 7277 3175 0 © The authors, except where otherwise stated All rights, including translation, reserved. 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Printed and bound in Great Britain by MPG Books, Bodmin, Cornwall PREFACE Concrete is a global material that underwrites commercial well-being and social development. Notwithstanding concrete's uniqueness, it faces challenges from new materials, environmental concerns and economic factors, as well as ever more demanding design requirements. Indeed, the pressure for change and improvement of performance is relentless and necessary. The Concrete Technology Unit (CTU) of the University of Dundee organised this Congress to address these issues, continuing its established series of events, namely, Creating with Concrete in 1999, Concrete in the Service of Mankind in 1996, Economic and Durable Concrete Construction Through Excellence in 1993 and Protection of Concrete in 1990. The event was organised in collaboration with three of the world's most recognised institutions: the Institution of Civil Engineers, the American Concrete Institute and the Japan Society of Civil Engineers. Under the theme of Challenges of Concrete Construction, the Congress consisted of three Seminars: (i) Composite Materials in Concrete Construction, (ii) Concrete Floors and Slabs, (iii) Repair, Rejuvenation and Enhancement of Concrete, and three Conferences: (i) Innovations and Developments in Concrete Materials and Construction, (ii) Sustainable Concrete Construction, (iii) Concrete for Extreme Conditions. In all, a total of 350 papers were presented from 58 countries. The Opening Addresses were given by Mr Jack McConnell MSP, First Minister of the Scottish Executive, Sir Alan Langlands, Principal and Vice-Chancellor of the University of Dundee, Mr John Letford, Lord Provost, City of Dundee, Professor Adrian Long, Senior Vice-President of the Institution of Civil Engineers, Dr Taketo Uomoto, Director of the Japan Society of Civil Engineers and Dr Terence Holland, President of the American Concrete Institute. The Congress had six Opening and six Closing Papers dealing with the main themes of the Seminars and Conferences. Opening Papers were presented by Professor Gerard Van Erp, University of Southern Queensland, Australia Dr Peter Seidler, Astradur Industrieboden, Germany and Professor Kyosti Tuttii, Skanska Teknik AB, Sweden, Professor Surendra Shah, Northwestern University, USA, Dr Philip Nixon, Building Research Establishment, UK and Mr Hans de Vries, Ministry of Transport, the Netherlands. Closing Papers were presented by Dr Gier Horrigmoe, NORUT Technology Ltd, Norway, Professor Andrew Beeby, University of Leeds, UK, Professor Peter Robery, FaberMaunsell, UK, Professor Heiki Kukko, VTT Building and Transport, Finland, Dr Mette Glavind, Danish Technological Institute, Denmark and Professor Yoshihiro Masuda, Utsunomiya University, Japan. The Congress was closed by Professor Peter Hewlett, Chief Executive of the British Board of Agrement, UK. The support of 23 International Professional Institutions and 32 Sponsoring Organisations was a major contribution to the success of the Congress. An extensive Trade Fair formed an integral part of the event. The work of the Congress was an immense undertaking and all of those involved are gratefully acknowledged, in particular, the members of the Organising Committee for managing the event from start to finish; members of the International Advisory and National Technical Committees for advising on the selection and reviewing of papers; the Authors and the Chairmen of Technical Sessions for their invaluable contributions to the proceedings. All of the proceedings have been prepared directly from the camera-ready manuscripts submitted by the authors and editing has been restricted to minor changes where it was considered absolutely necessary. Dundee Ravindra K Dhir September 2002 Chairman, Congress Organising Committee INTRODUCTION All concrete structures deteriorate as the effects of structural and environmental loading take place over time. Sometimes unforeseen circumstances can occur that produce more rapid degradation than was initially envisaged. Whatever the particular type of exposure or deterioration mechanism involved, all these processes lead to the same point - an unacceptable loss of performance. This may be structural or aesthetic, but the result is that there is a need to repair, rejuvenate or enhance concrete. To enable this, what has happened to the materials involved must be clearly identified, understood and quantified. This is often a difficult task, as there are no 'black boxes' that can record the history of the particular element. The forensics of deterioration can, therefore, be both problematic and costly. Having said this, our understanding of the mechanisms of concrete deterioration has greatly improved over recent years and research has begun to identify, if not quantify, the underlying fundamental chemistry and materials science involved. There are new high technology analytical methods that can probe the nature of concrete down to its nano-scale. Undoubtedly these techniques will provide new insights to the effects of degradation processes and, thereby, enhance repair and rehabilitation methods. Allied to this there has been a growing realisation that there is need for partnership between the scientific and engineering research communities. Without this, research can lack direction and practice can stagnate. Innovation and development are rarely straightforward but there is much to be learned from fast moving, technology-driven industries such as IT and aerospace engineering, where continuous innovation is embraced as a key business process. Even into the 21st century this still seems a paradigm away from our industry. However, even the concrete construction industry does not stand still and is being required to provide ever higher performance for the client, both technically and economically. In turn, this will bring new challenges for the repair industry. Sustainable construction has turned the spotlight on the way we manage our building and infrastructure and far from being seen as a route to taxation of materials and wastes, it should be seen as an opportunity to re-engineer the maintenance methods and end-of-life disposal. The lessons of other industries are that the adoption of these strategies sharpens work practices and enhances productivity, while protecting the environment. All of these point towards the fact that the processes of repair, rejuvenation and enhancement of concrete structures must be intimately woven into initial design and construction and should not be regarded as a separate engineering system that simply turns up when something has gone wrong. It is these systems that provided the basis for this Seminar. The Proceedings of this Seminar; 'Repair, Rejuvenation and Enhancement of Concrete' dealt with these subjects and the issues raised, under three clearly defined themes: (i) Degradation of Concrete in Structures, (ii) Assessment and Repair Techniques and (iii) Enhancement of Existing Structures. Each theme started with a Keynote Paper presented by the foremost exponents in their respective fields. There were a total of 48 papers presented during this International Seminar, which have been compiled to form these Proceeding Dundee R K Dhir September 2002 M R Jones L Zheng ORGANISING COMMITTEE Concrete Technology Unit Professor R K Dhir OBE (Chairman) Dr M D Newlands (Secretary) Professor P C Hewlett British Board of Agrement Professor T A Harrison Quarry Products Association Professor V K Rigopoulou National Technical University of Athens, Greece Dr S Y N Chan Hong Kong Polytechnic University Dr N Y Ho L & M Structural Systems, Singapore Dr M R Jones Dr MJ McCarthy Dr T D Dyer Dr K A Paine Dr L J Csetenyi Dr J E Halliday Dr L Zheng Dr S Caliskan Dr A Iordanidis Ms P I Hynes (Congress Assistant) Mr S R Scott (Unit Assistant) INTERNATIONAL ADVISORY COMMITTEE Dr C Andrade, Director oflETCC Institute of Construction Sciences Eduardo Torroja, Spain Professor G Balazs, Head of Department Budapest University of Technology, Hungary Professor Y Ballim, Associate Professor University of the Witwatersrand, South Africa Professor A Bentur, Head Division of Building Materials Technion Israel Institute of Technology, Israel Professor J M J M Bijen, Professor Delft University of Technology, Netherlands Professor A Brandt, Head of Department Institute of Fundamental Tech Research, Poland Professor K-J Byun, Dean/Professor in Concrete Engineering Yonsei University, Korea Dr J-M Chandelle, Chief Executive CEMBUREAU, Belgium Professor T-P Chang, Professor National Taiwan University of Science & Technology, Taiwan Professor M Collepardi, Professor Politecnico Di Milano, Italy Dr J Duncan, Manager, Building Industry Research BRANZ, New Zealand Professor RI Gilbert, Head of School University of New South Wales, Australia Professor S Ikeda, Professor Yokohama National University, Japan Professor B L Jensen, Danish Technological Institute, Denmark Dr H Justnes, Chief Scientist SINTEF Civil & Environmental Engineering, Norway Professor V Kristek, Head of Department Czech Technical University, Czech Republic Dr A K H Kwan, Associate Dean of Engineering University of Hong Kong, Hong Kong Professor F de Larrard, Director MMCER LCPC Centre de Nantes, France INTERNATIONAL ADVISORY COMMITTEE (CONTINUED) Professor R W Lindberg, Professor Tampere University of Technology, Finland Dr H-U Litzner, Senior Chief Executive German Concrete Society (DBV), Germany Mr J E McDonald, Research Civil Engineer US Army Corp of Engineers, USA Professor S Mirza, Professor McGill University, Canada Mr J V Paiva, Head, Building Department LNEC, Portugal Dr T Philippou, Manager Heracles General Cement Company, Greece Mr S A Reddi, Deputy Managing Director Gammon India Limited, India Professor F Saje, Professor of Concrete Structures University of Ljubljana, Slovenia Professor S P Shah, Director ACBM Northwestern University, USA Professor HER Sommer, Consultant Austria Dr S Tangtermsirikul, Head of School of Civil Engineering Thammasat University, Thailand Professor K Tuutti, Director Skanska Teknik AB, Sweden Professor T Uomoto, Head of Uomoto Concrete Laboratory University of Tokyo, Japan Dr O H Wallevik, Head of Concrete Division Icelandic Buidling Research Institute, Iceland Professor T H Wee, Associate Professor National University of Singapore, Singapore Professor M A Yeginobali, Director, R&D Institute Turkish Cement Manufacturers Association, Turkey Professor H M Z Al-Abideen, Deputy Minister Ministry of Public Works and Housing, Saudi Arabia NATIONAL TECHNICAL COMMITTEE Professor S A Austin Professor of Structural Engineering, Loughborough University Professor A W Beeby Professor of Structural Design, The University of Leeds Professor T Broyd Research & Innovations Director, W S Atkins Professor J H Bungey Head of Department, The University of Liverpool Mr N Clarke Publications Manager, The Concrete Society Mr G Cooper Development Director, Fosroc International Ltd Mr S J Crompton Divisional Manager, RMC Readymix Ltd Dr S B Desai OBE Visiting Professor, University of Surrey Professor R K Dhir OBE (Chairman) Director, Concrete Technology Unit, University of Dundee Dr K Elliott Senior Lecturer, University of Nottingham Dr S Garvin Director (Scotland), Building Research Establishment Professor F P Glasser Professor, University of Aberdeen Mr P G Goring Technical Director, John Doyle Construction Professor T A Harrison BRMCA Consultant, Quarry Products Association Professor P C Hewlett Chief Executive, British Board of Agrement Mr A Johnson Divisional Director and Manager, Mott MacDonald Special Services Dr M R Jones Senior Lecturer, Concrete Technology Unit, University of Dundee Professor R J Kettle Head of Department, Aston University Mr P Livesey National Technical Services Manager, Castle Cement Limited NATIONAL TECHNICAL COMMITTEE (CONTINUED) Professor A E Long Dean of Faculty of Engineering, Queens University Belfast Mr N Loudon Senior Technical Adviser, Highways Agency Mr A C Mack Operations Director, Bovis Lend Lease (Scotland) Ltd Professor P S Mangat Head, Civil Engineering & Construction, Sheffield Hallam University Mr G G T Masterton Director, Babtie Group Professor G C Mays Deputy Principal, Cranfield University Professor W J McCarter Professor, Heriot-Watt University Dr J Moore Director, Standards & Technical, British Cement Association Dr P J Nixon Director, Centre for Concrete Construction, Building Research Establishment Mr M Peden Partner, W.A. Fairhurst & Partners Dr W F Price Senior Research Manager, British Cement Assocation Professor P C Robery Divisional Director - Midlands, Maunsell Ltd Mr J M Ross Chairman, Blyth & Blyth Consulting Engineers Dr R H Scott Reader in Engineering, University of Durham Dr I Sims Director (Materials), STATS Limited Professor G Somerville OBE Independent Consultant Mr P Titman Quality and Environment Manager, Edmund Nuttall Ltd Dr P R Vassie Research Fellow, Transport Research Laboratory Professor S Wild Head, Building Materials Research Unit, University of Glamorgan COLLABORATING INSTITUTIONS Institution of Civil Engineers, UK American Concrete Institute Japan Society of Civil Engineers SPONSORING ORGANISATIONS WITH EXHIBITION Aggregate Industries pic Babtie Group British Board of Agrement British Cement Association Building Research Establishment Caledonian Slag Cement Castle Cement Limited CEMBUREAU, Belgium Danish Technological Institute, Denmark Degussa Construction Chemicals, Italy Dundee City Council Elkem Materials Ltd FaberMaunsell Fosroc International Ltd Heidelberg Cement, Germany Heracles General Cement Company, Greece Institution of Civil Engineers John Doyle Construction Lafarge Cement UK Makers UK Ltd MBT Admixtures Netzsch Instruments, Germany North East Slag Cement Palladian Publications RMC Readymix Ltd Rugby Cement ScotAsh Ltd