Sprayed concrete : properties, design, and application

393 Pages·1995·378.517 MB·English

by  Robins, P. J., Austin, S. A

Sprayed Concrete:
Properties, Design and Application
edited by
.J
S.A.Austin & P .Robins
Senior Lecturers in Structural Engineering,
Department of Civil & Building Engineering,
Loughborough University of Technology,
Loughborough, UK
Whittles Publishing
Typeset by
Whittles Publishing Services,
Published by:
Whittles Publishing,
Roseleigh House,
Latheronwheel, Caithness, KWS 6DW,
Scotland
© 1995 S.A.Austin & P.J.Robins
All rights reserved.
No part of this publication may be reproduced,
stored in a retrieval system, or transmitted,
in any form or by any means, electronic,
mechanical, recording or otherwise
without the prior permission of the Publishers.
British Library Cataloguing in Publication Data
Sprayed Concrete: Properties, Design and
Application
I. Austin, Simon A. II. Robins, Peter J.
620.136
eISBN 978-1-84995-285-9
The publisher assumes no responsibility for any injury and/or damage to persons or property, or
consequential loss, from the use or implementation of any methods, instructions, ideas or materials
contained within this book. All operations should be undertaken in accordance with existing legislation
and recognised trade practice. Whilst the information and advice in this book is believed to be true and
accurate at the time of going to press, the authors and publisher accept no legal responsibility or liability
for any errors or omissions that may be made.
11
Contributors
S.A.Austin Senior Lecturer in Structural Engineering, Department of Civil
and Building Engineering, Loughborough University of
Technology, Loughborough, LE11 3TU
N.Barton Technical Adviser, Norwegian Geotechnical Institute, P.O.Box
3930, Ullevaal Hageby, N-0806 Oslo, Norway
G.Daws Graham Daws Associates Ltd., Amber Business Centre,
Riddings, Derbyshire, DESS 4BR
S.H.Gebler Senior Principal Evaluation Engineer, Construction Technology
Laboratories, Inc., 5420 Old Orchard Road, Skokie, Illinois,
60077-1030, USA
K.Gordon International Marketing Manager, Concrete Repair, Fosroc
International Ltd., 285 Long Acre, Nechells, Birmingham, B7
SJR
£.Grimstad Senior Engineering Geologist, Norwegian Geotechnical
Institute, P.O.Box 3930, Ullevaal Hageby, N-0806 Oslo,
Norway
J.P.Holtmon A!S Veidekke, P.O.Box 111, 1314 Skui, Norway
E.S.King Associate, Mott MacDonald Special Services Division, St Anne
House, 20/26 Wellesley Road, Croydon, CR9 2UL
T.A.Melbye Director, Underground Construction Group, MBT Holding,
Meynadier AG, Vulkanstrasse 110, 8048 Zurich, Switzerland
B.R.Maidl Professor of Construction Process Technology, Tunnel
Construction and Construction Operations, Fakultat for
Bauingenieurwesen, Ruhr-Un iversitat Boch um,
Universitatsstrasse 150, 44801 Bochum, Germany
D.C.Miller Consultant, Compton House, The Paddock, Tickhill,
Doncaster, South Yorkshire, DNl 1 9HS .
D.R.Morgan AGRA Earth & Environmental Limited, 2227 Douglas Road,
Burnaby, B.C., VSC SA9, Canada
O.A.Opsahl Senior Vice President, A/S Veidekke, P.O.Box 111, 1314 Skui,
Norway
A.Palmstrnm Senior Engineering Geologist, Norwegian Geotechnical
Institute, P.O.Box 3930, Ullevaal Hageby, N-0806 Oslo,
Norway
P.J.Robins Senior Lecturer in Structural Engineering, Department of Civil
and Building Engineering, Loughborough University of
Technology, Loughborough
P.Sommavilla Aliva Ltd., Bellikonerstrasse, 218 P.O.Box CH 8967, Widen,
Switzerland
G.Taylor Institute of Concrete Technology, P.O.Box 255, Beaconsfield,
Bucks., HP9 lJE
B.S.Wyatt Cathodic Protection Manager, Tarmac Global, Ward Street,
Wolverhampton, WV2 2PJ
11l
JV
Contents
Section I - Sprayed Concrete as a Construction Material
Introduction to Sprayed Concrete
S.A.Austin
1.1 Why this book? 1
1.2 Terminology 2
1.3 Historical background 2
1.4 Current and future trends 4
References 6
2 Materials 7
P.J.Robins
2.1 Introduction 7
2.2 Cements 7
2.3 Supplementary cementing materials 8
2.4 Aggregates 9
2.5 Admixtures 11
2.6 Fibres 12
2.7 Mesh and bar reinforcement 13
References 14
3 Specialist Pre-blended Materials 16
K.Gordon
3.1 Introduction 16
3.2 Reasons for their use 16
3.3 New construction and repair application 19
3.4 Mining applications 22
3.5 Refractory applications 23
3.6 Effects of spraying 24
3.7 Production methods 27
References 29
4 Production and Installation 31
S.A.Austin
4.1 Introduction 31
4.2 Dry process production 31
4.3 Wet process production 36
4.4 Application 39
4.5 Losses 41
4.6 Preparation, formwork and finishing 47
References 50
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CONTENTS
5 Physical Properties 52
P.J.Robins
5.1 Introduction 52
5 .2 Plastic properties 52
5.3 Compressive strength 54
5.4 Flexural strength 57
5.5 Flexural toughness 63
5.6 Impact resistance 72
5.7 Bond to substrate 72
5.8 Shrinkage 75
5.9 Water absorption 77
5.10 Permeability 79
5 .11 F reeze!thaw resistance 79
5.12 Reinforcement corrosion 81
References 82
Section II Design and Installation
6 Materials Selection, Specification and Quality Control 87
S.A.Austin
6.1 Scope 87
6.2 Mix selection and design 87
6.3 Reinforcement selection and design 91
6.4 Specification 98
6.5 Quality control and testing 105
References 109
7 Design for Structural Application 113
E.S.King
7.1 Introduction 113
7.2 Choice of material and method - new structures 113
7.3 Choice of material and method - existing structures 118
7.4 Structural design - new structures 123
7.5 Structural design - existing structures 125
7.6 Detailed design - new structures 127
7.7 Detailed design - existing structures 130
7.8 Specification of material - new structures 133
7. 9 Specification of material - existing structures 139
7.10 Quality assurance 142
7.11 Examples 143
7.12 Conclusions 148
References 148
8 Design of Tunnel Support 150
N.Barton, £.Grimstad and A.Palmstrnm
8.1 Introduction 150
8.2 The New Austrian Tunnelling Method (NATM) 151
8.3 Norwegian Method of Tunnelling 157
8.4 Conclusion 168
References 170
Vl
CONTENTS
9 Equipment for the Production of Sprayed Concrete 171
B.R.Maidl and P.Sommavilla
9.1 Spraying methods 171
9.2 Mixture preparation and placement 180
9.3 Dry spraying equipment 181
9.4 Wet spraying equipment 185
9.5 Automatic nozzle operation 190
9.6 Auxiliary equipment 196
9.7 Equipment for repair work 199
9.8 Special requirements for work in mines 202
References 202
10 Construction Practice and Quality Control 204
S.H.Gebler
10.1 Site set-up 204
10.2 Crew organization 204
10.3 Scaffolds and other equipment 207
10.4 Substrate surface preparation 208
10.5 Formwork 209
10.6 Joints 209
10.7 Steel reinforcement 210
10.8 Batching and mixing 212
10.9 Shotcrete placement 214
10.10 Finishing, curing and climate 218
10.11 Quality assurance 221
References 227
11 Special Sprayed Concretes 229
D.R.Morgan
11.1 Introduction 229
11.2 Cementing materials 230
11.3 Supplementary cementing materials 231
11.4 Admixtures 232
11.5 Fibre reinforcement 235
11.6 Mixture proportioning 237
11.7 Batching, mixing and supply 240
11.8 Application and plastic properties 244
11.9 Properties of hardened sprayed concrete 248
11.10 Applications 259
11.11 Future developments 262
References 263
12 Site Safety 266
D.Miller
12.1 Introduction 266
12.2 Plant and equipment 266
12.3 Materials 267
12.4 Working environment 267
12.5 Work stations 269
12.6 Protective clothing 270
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CONTENTS
12.7 Welfare facilities 272
12.8 Training and certification 272
12.9 Associated operations 273
12.10 Accidents 274
12.11 Conclusion 274
References 275
Section III - Applications
13 New Construction 276
G.Taylor
13.1 Introduction 276
13.2 Reasons for use 276
13.3 Structural form 277
13 .4 Special uses 279
13.5 Substrates 280
13.6 Formwork 280
13.7 Reinforcement 281
13.8 Finishes 282
13.9 Economics 283
13.10 Examples 284
Bibliography 286
14 Repair 287
G.Taylor
14.1 Introduction 287
14.2 Diagnosis of defect causes 288
14.3 Preparation 288
14.4 Reinforcement treatment 289
14.5 Mixes 291
14.6 Procedures 291
14.7 Curing 293
14.8 Examples and case studies 293
Bibliography 296
15 Rock Stabilization and Underground Support 297
G.Daws
15 .1 Introduction 297
15.2 Slope stabilization 297
15.3 Underground support 304
15.4 Rockbolting systems 308
References 313
Appendix 15.1 Test procedure to investigate the effectiveness of
resin anchored rockbolts 314
16 Shotcrete for Rock Support 317
T.Melbye, O.Opsahl andJ.Holtmon
16.1 Introduction 317
16.2 Dry-mix method 318
Vlll
CONTENTS
16.3 Wet-mix method 322
16.4 Mix design for wet spraying 324
16.5 Steel-fibre spayed concrete for rock support 331
16.6 New advanced shotcrete admixtures 336
16.7 The MEYCO TCC system 340
16.8 Example of wet-mix shotcrete 345
16.9 Equipment 346
16.10 Active mechanisms of shotcrete on rock 348
16.11 Spraying techniques 352
16.12 Outlook: The potential for shotcrete applications 356
Bibliography 356
17 Cathodic Protection of Reinforced Concrete 357
B.S.Wyatt
17.1 Introduction 357
17.2 Anode systems 358
17.3 Overlays for anodes 364
17.4 Selection and design of anode systems 367
17.5 Conclusions 371
References 373
Index 375
IX