ADHESION PROBLEMS IN THE RECYCLING OF CONCRETE

Transcription

1 ADHESION PROBLEMS IN THE RECYCLING OF CONCRETE

2 NATO CONFERENCE SERIES I II III IV V VI Ecology Systems Science Human Factors Marine Sciences Air-Sea Interactions Materials Science VI MATERIALS SCIENCE Volume 1 Molecular Metals Edited by William E. Hatfield Volume 2 Volume 3 Volume 4 Materials for Advanced Batteries Edited by D. W. Murphy, J. Broadhead, and B. C. H. Steele Adhesion in Cellulosic and Wood-Based Composites Edited by John F. Oliver Adhesion Problems in the Recycling of Concrete Edited by Pieter C. Kreijger

3 ADHESION PROBLEMS IN THE RECYCLING OF CONCRETE Edited by Pieter C. Kreijger Eindhoven University of Technology Eindhoven, The Netherlands Published in cooperation with NATO Scientific Affairs Division PLENUM PRESS NEW YORK AND LONDON

4 Library of Congress Cataloging in Publication Data NATO Advanced Research Institute on Adhesion Problems in the Recycling of Concrete (1980 : Saint-Remy-Ies-Chevreuse, France) Adhesion problems in the recycling of concrete [proceedings! (NATO conference series. VI, Materials science; v. 4) Bibliography: p. Includes index. 1. Concrete-Recycling-Congresses. I. Kreijger, Pieter C. II. Title. III. Series. TA440.N ' AACR2 ISBN-13: : / e-isbn-13: Proceedings of a NATO Advanced Research Institute on Adhesion Problems in the Recycling of Concrete, held November 25-28,1980, in Saint-Remy-Ies-Chevreuse, France Plenum Press, New York A Division of Plenum Publishing Corporation 233 Spring Street, New York, N.Y Softcover reprint of the hardcover 1st edition 1981 All rights reserved No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording, or otherwise, without written permission from the Publisher

5 PREFACE The building explosion during the years will inevitably lead to increased demolition in the next decades since the lifetime distribution of structures no longer fulfills its functional social requirements in an acceptable way. In the building period mentioned there was a great increase in reinforced and prestressed concrete construction. Consequently there is now more and more concrete to be demolished. Increasingly severe demands will be made upon demolition technology, including the demand for human- and environment-friendly techniques. On the other hand, the possibility of disposing of debris by dumping is steadily diminishing, especially close to major cities and generally in countries with a high population density. At the same time in such countries and in such urban areas a shortage of aggregates for making concrete will develop as a result of restrictions on aggregate working because of its effect on the environment and because of the unavailability of aggregate deposits due to urban development. From the foregoing it follows that recycling and re-use of environment- and human-friendly demolished and fragmented building rubble should be considered. The translation of this general problem into terms of materials science is possible by forming clear ideas of adhesion and cohesion: the whole process of demolition, fragmentation, and recycling or re-use of concrete is to break the bonding forces between atoms and molecules and to form new bonds across the interfaces of various particles of either the same nature or a different nature. Studies of these processes are especially important since it is now known that there is a good chance that recycling and re-use of demolished buildings will be economically possible. Consequently an evaluation of existing knowledge applied to the adhesion problems in the recycling of concrete will be of great importance and could be realized by a (first) conference on this topic, bringing together experts who are specialists in physical, chemical, and/or fracture mechanical aspects of materials science, with the aim of discussing and applying their particular knowledge to the adhesion and cohesion aspects mentioned. v

6 vi PREFACE It was a fortunate coincidence that the formulation of the problem as given in the preceding paragraph just fitted in with the program of the Special Program Panel on Materials Science of the Scientific Affairs Division of NATO. Their acceptance of our proposal to hold such a Conference made it possible to realize this Advanced Research Institute on "Adhesion Problems in the Recycling of Concrete" at Saint-R~y.. les-chevreuse, November Without their financial help this A.R.I. would not have been possible. The preparation of the A.R.I. was set up by a Programming and Organizing Committee originally consisting of Dr. L.H. Everett (UK), Dr. G. Frohnsdorff (USA), Prof. Dr. Ing. H.K. Ri1sdorf (W. Germany), Prof. Ir. P.C. Kreijger (The Netherlands), Dr. J.J. Mills (USA), and Prof. Dr. F.R. Wittmann (at that time, The Netherlands). Later on Dr. Everett and Prof. Wittmann had to resign owing to special circumstances. NATO appointed Prof. Kreij ger Director of the A.R.I., and he took care of and is responsible for the realization of the organization. We are grateful to the "Union Technique Interprofessione11e" of the "Federation Nationa1e du Batiment" in Paris for their consent to make use of all facilities of their research center "Domaine de Saint Paul" at Saint-Reny-1es-Chevreuse. Our special gratitude goes to Mrs. M. Geude1in of the "Direction de 1a Recherche," "Relations Internationa1es," who not only made all organizational preparations for a four-day stay of about thirty persons at the research center, but also looked after technical facilities (Mr. Millet) and typing and copying capacity (Mrs. Vallot) during the meetings, and kept exe11ent minutes and prepared reviews of the various discussions at the A.R.I., partly assisted by Mrs. M.J. Rubens as a freelance second secretary. Looking back to this first scientific conference on the recycling of concrete, consisting of a series of invited lectures, giving the state of the art of related background fields, and (eight) workshops under such headings as "Fragmentation," "Contamination," "Recycling," "Re-use," and "Future demolition-friendly materials," with invited introductory lectures, I wish to thank all participants for the cooperative, cheerful, and positive manner in which they approached the assigned work, especially the difficult task of preparing workshop reports. We realize that the success of our discussions was stimulated to a great extent by the great effort that was put into papers and introductory lectures, and our gratitude goes to the authors; we are grateful for all special contributions given during the workshop sessions or later on, and which have been incorporated into these Proceedings.

7 PREFACE ~i In line with the foregoing, the Proceedings of this A.R.I. are composed of four parts: Part 1 - Organization of the A.R.I. Part 2 - Lectures, discussions, and general discussion. Part 3 - Introductory lectures to workshops, workshop reports, and contributions to workshops. Part 4 - Concluding remarks. The information that has become available reveals numerous opportunities for new and demanding research in this field and should provide helpful directions to those who are already involved with this research, to those who wish to enter the field, and to those who are responsible for making administrative decisions. Finally I want to thank my secretary, Mrs. D.M. Vermeltfoort Danen, for her organizational assistance and the care taken with all correspondence. Eindhoven December 1980 Pieter C. Kreijger

8 CONTENTS PART ORGANIZATION Introduction Program Participants Proceedings PART 2 LECTURES, DISCUSSIONS, AND GENERAL DISCUSSION Introduction and stating the problems - p c. Kreij ger Additional information given during the presentation: Case study of the Netherlands - P.C. Kreijger The structure of concrete: a macroscopic view - C.D. Pomeroy 2.2 Discussion 3.1 Principles of adhesion - bonding in cement and concrete - D. Tabor 3.2 Discussion Contamination problems in the recycling of concrete - J.F. Young Discussion Fracture energy of concrete - H.K. Hilsdorf and S. Ziegeldorf Discussion Adsorption sensitive fracture and fragmentation - J.J. Mills Discussion ix

9 x CONTENTS Economics of concrete recycling in the United States - S. Frondistou-Yannas Discussion General Discussion PART 3 INTRODUCTORY LECTURES TO WORKSHOPS, MINUTES OF WORKSHOPS, WORKSHOP REPORTS, AND CONTRIBUTIONS TO WORKSHOPS Workshop 1 - Fragmentation of plain and reinforced concrete Minutes of workshop 1 - M. Geudelin 1.2 Contribut ions Demolition techniques for concrete structures - P. Lind sell Observed energy - dissipative features of crackpro pagation in mortar - S. Mindess and S. Diamond Workshop 4 - Fragmentation of prestressed concrete Introductory lecture: Demolition of prestressed concrete structures - P. Lindsell Minutes of workshop 4 - M. Geudelin Contributions Explosives for localized cutting in concrete - C. Molin Workshop 5 - Contamination effects on fragmentation, fibre and polymer concrete Introductory lecture: Materials characterization for fragmentation - S.P. Shah Report on workshop 5 - S. Mindess Contributions Correlation between fracture toughness and zeta potential of cementstone - A.T.F. Neerhoff Workshop 8 - Fragmentation of all types of concrete - research needs Minutes of workshop 8 - M. Geudelin Contributions Recommended flow chart for future research activities concerning demolition and fragmentation of concrete - O. Ishai Workshop 2 - Recycling of concrete (aggregates for use in concrete) Introductory lecture: Crushed concrete as concrete aggregate - B. Mather

10 CONTENTS Minutes of workshop 2 - M. Geudelin Report on workshop 2 - S. Frondistou-Yannas Contributions Classification of recycled aggregate, proposed in the Netherlands - P.C. Kreijger Fragmentation and recycling of reinforced concrete, some research results - Ir. C. De Pauw... The role of a polymeric interlayer in improving mechanical characteristics of recycled concrete - o. Isbai.... Workshop 3 - Re-use of concrete (other than as aggregate) Introductory lecture: Recycling of concrete into new applications - R.L. Berger and S.H. Carpenter Minutes of the presentation of the introductory lecture - M. Geudelin Report on workshop 3 - C.D. Pomeroy Contributions Example of re-use of concrete in France - R. Sierra Reflecting properties of a road surface - J.H. de Boer 7. Workshop 7 - Contamination effects on recycling and re-use Introductory comments - G. Frohnsdorff 7.2'.1 Minutes of workshop 7 - M. Geudelin Report on workshop 7 - G. Frohnsdorff 7.3 Contributions The effect of gypsum on length change and strength of portland- and portland blastfurnace cementstone specimen - P.C. Kreijger The influence of contaminants on the quality and the behaviour of recycled concrete - Ir. H. Lambotte and Ir. C. De Pauw Workshop 8 - Future demolition-friendly materials. Introductory comments - D.M. Roy Minutes of workshop 6 - M. Geudelin Contributions Some notes regarding the performance of waste materials and concrete in building components - P C. Kreij ger PART 4 CONCLUDING REMARKS Concluding remarks - P.C. Kreijger List of Participants Index xi