Sprayed concrete technology: the proceedings of the ACI/SCA International Conference on Sprayed Concrete/Shotcrete, 'Sprayed concrete technology for the 21st century' held at Edinburgh University from 10th to 11th September 1996

Book Cover......Page 1
Title......Page 4
Copyright......Page 5
Contents......Page 6
Preface......Page 10
Acknowledgments......Page 13
PART ONE  ADMIXTURES......Page 14
1  Introduction......Page 15
3  Materials, mixtures and operating procedures......Page 17
4.3  Air void characteristics......Page 18
4.4  Salt scaling resistance......Page 19
7  References......Page 20
Abstract......Page 21
1  Introduction......Page 22
2  Mix Design for the Didcot Strengthening Project......Page 23
4  Results of the Didcot Strengthening Project......Page 25
5  Discussion......Page 30
5.2  Experimental Details......Page 31
6.1  Compressive Strength......Page 32
6.2  Effect of air pressure on rebound......Page 33
7  Conclusions......Page 34
9  References......Page 35
Abstract......Page 37
2  Alkali-free, non caustic accelerators......Page 38
3  The consistency control system......Page 39
3.1  The Hvassum Road Tunnel, Norway......Page 40
5  Benefits of modern SFRS......Page 41
5.1  Quality and durability......Page 42
5.3  Technical Properties......Page 43
5.4  Time and Economy......Page 44
7  References......Page 46
Abstract......Page 51
2.2  Alkalifree non-toxic powder accelerators......Page 52
3.1  Chemical reactivity......Page 53
3.2  Early strength and ultimate strength developments......Page 54
3.4  Leaching tests and effluent values......Page 55
4  Tunnel site results......Page 58
PART TWO  APPLICATIONS......Page 60
1  The Problem......Page 61
2  Cathodic Protection......Page 62
3  Realkalisation......Page 63
4  Desalination......Page 64
6  The Repair Process......Page 65
Acknowledgements......Page 67
Introduction......Page 68
Dome design and construction......Page 69
Shotcrete Mix......Page 71
Barrel-Vault Roof Sections......Page 72
Report Card......Page 73
References......Page 74
1  Introduction......Page 75
2  Laminated ferrocement (LFC)......Page 76
3  Horizontal slipform......Page 77
4  Vertical slipform.......Page 78
5  Applications......Page 79
7  References......Page 81
1  Introduction......Page 83
2  Convincing the designers......Page 84
3  Primary and secondary lining......Page 86
4  Advantages......Page 87
5  Research......Page 88
Conclusions......Page 91
1  Introduction......Page 93
2.1  Test arch details......Page 95
2.2  Sprayed concrete strengthening of test arch......Page 96
3.2  Strengthened arch tests......Page 98
3.3  Comparison with MEXE and finite element methods......Page 99
4  Conclusions......Page 101
6  References......Page 102
1  Introduction......Page 103
2  Reinforcing......Page 104
3.1  Ground wires......Page 105
4  Shotcrete application......Page 107
5  Joints......Page 108
6  Quality control......Page 109
Curing......Page 111
6  REFERENCES......Page 112
PART THREE  FIBRES......Page 114
1  Introduction......Page 115
4  Results......Page 116
6  References......Page 120
1  Introduction......Page 121
2.1  Some previous models......Page 122
2.2  Basic concepts of the proposed model......Page 123
3.2  Materials and mix design......Page 124
3.3  Specimen preparation and testing procedure......Page 125
4  Results and discussion......Page 126
6  References......Page 129
PART FOUR  MATERIALS......Page 131
1  Introduction......Page 132
2  Spray cement......Page 133
3  System-requirements for preparation and conveyance of humid aggregates......Page 135
4.2  Testing technique......Page 136
4.3  Test results......Page 137
5  Practical application at site......Page 138
6  Summary......Page 139
7  Reverences......Page 140
Abstract......Page 141
1  Introduction......Page 142
3  Shotcrete supply and application......Page 143
4  Hardened shotcrete properties......Page 146
5  Discussion of Test Results......Page 147
7  Acknowledgements......Page 151
Abstract......Page 152
1.1  Case study 1: Rhuallt Hill......Page 153
2  Design......Page 154
Construction and quality assurance......Page 155
Drainage......Page 157
Specification......Page 158
REFERENCES......Page 159
PART FIVE  REPAIR......Page 160
1  Introduction......Page 161
2.2  Carbonation tests......Page 162
2.4  Half cell potential testing......Page 163
2.5  Petrographic examination......Page 164
3  Appraisal of results......Page 165
4  Repair Options......Page 166
5  Material selection......Page 168
6  Site operations......Page 169
8  References......Page 170
1  Introduction......Page 171
2  Current position in wet and dry process sprayed concrete......Page 172
3  Concrete Repair Scenarios......Page 173
4  Pumping and spraying trials......Page 177
5.  Conclusions and further work......Page 180
References......Page 181
1  Introduction......Page 182
2.1  Workability and ease of placing......Page 183
2.4  Basic requirements......Page 184
3.1  History......Page 185
3.2.5  Direct tensile strength.......Page 186
3.3  Experimentation......Page 187
5  References......Page 189
1  Introduction......Page 191
3.1  Altofts River Bridge......Page 192
3.2  River Aire Bridge......Page 194
3.3  Motorway Overbridge Deflection Points......Page 196
3.4  Oxford Road Bridge Abutment Repairs......Page 197
6  Acknowledgements......Page 198
2  Causes......Page 199
3.  Slab Scaling:......Page 200
5  Rehabilitation......Page 201
7  Surface preparations......Page 202
9  Quality Control Requirements......Page 203
Sprayed Base Coat......Page 204
13  Conclusions......Page 205
1  Introduction......Page 207
2  Model studies......Page 208
4  Material properties......Page 210
5  Structural performance......Page 211
8  References......Page 214
1  Introduction......Page 216
2  Details of bridge sites......Page 217
3.1  Monitoring equipment......Page 218
4  Details of repair materials......Page 219
5  Preliminary results and discussion......Page 221
6  Interim conclusions......Page 223
8  References......Page 224
PART SIX  SPECIFICATION......Page 226
1  Introduction......Page 227
3.  Shotcrete quality and quantity......Page 229
4.  Shotcrete failure, its significance and the avoidance of failure......Page 230
5.1  Types of rockbolt......Page 231
5.2  Rockbolt proof tests......Page 232
5.3  Proof tests at the east portal of the Ayran tunnel......Page 233
6.2  Rock bolts......Page 235
7  References......Page 236
1  Defining Standards......Page 237
3  Concrete/Shotcrete BeginningsS......Page 238
5  Standards Sources......Page 239
5.2  ASTM......Page 240
6  Properties of Shotcrete......Page 241
7.2  Manufacture/Production......Page 242
8  Future Standards......Page 243
9  Closure......Page 244
1  Standards......Page 245
3  Requirements for Repair by Sprayed Concrete......Page 247
4  References......Page 249
1  Introduction......Page 250
2.2  Properties of Concrete......Page 251
2.5  Plant......Page 252
3.1  General......Page 253
3.3  Workmanship demonstration......Page 254
3.5  Marking......Page 255
Acknowledgements......Page 257
Appendix No. 1......Page 258
PART SEVEN  SPRAY PROCESS......Page 259
1  Introduction......Page 260
3  Materials and Method......Page 262
Aggregate Velocity vs Size......Page 263
Fiber Velocity vs Shape......Page 264
6  References......Page 266
1.1  Bingham model......Page 269
1.2  Ageing......Page 271
1.3  Effect of composition and description of the workability box......Page 273
2  Pumpability......Page 274
3.1  Relationship between shootability and rheology......Page 275
3.3  Workability box......Page 277
4  Conclusion......Page 278
6  References......Page 279
PART EIGHT  TEST METHODS AND PERFORMANCE......Page 280
1  Introduction......Page 281
2  Performance Testing......Page 282
3  In-Situ Testing......Page 283
4  Interpretation of Pull-Off Tests......Page 284
6  References......Page 286
Abstract......Page 287
2  Perspective......Page 288
3  Review of repair envelope and predicting dimensional stability......Page 289
4.1  Silica fume......Page 290
4.6  Polymer......Page 291
5  Discussion of selected mix designs......Page 292
7  Field observation......Page 293
8  Laboratory results......Page 294
9  Field performance......Page 295
12  References......Page 296
13  Acknowledgments......Page 297
Abstract......Page 298
2.1  Base slab details......Page 299
2.2  Sprayed concrete details......Page 300
2.3  Experimental procedures......Page 301
3.1  Mechanical tests......Page 302
3.2  Slant shear test results......Page 303
3.3  Petrographic report......Page 304
4  Experimental investigation—phase II......Page 305
4.1  Reinforced Sprayed Concrete Curtailment......Page 306
4.3  Horizontal shear study—Double shear test......Page 307
5  Experimental results—phase II......Page 309
5.1  Horizontal shear capacity—comparison......Page 310
6.1  Phase I......Page 313
6.2  Phase II......Page 314
7  Acknowledgements......Page 315
Author Index......Page 316
Keyword index......Page 317