Testing of Concrete in Structures: Fourth Edition

More documents

Recommendations

Info

Partially destructive strength tests 109load method gave much closer agreement between correlations for differentaggregate types (34).The chief advantage of the internal fracture test lies in the ability to usea general strength calibration curve for natural aggregates relating only tothe loading method. Despite the variability, localized surface nature anddamage caused, this may be of particular value in situations where a strengthestimate of in-situ concrete of unknown age or composition is required.This is especially true for slender members with only one exposed surfacewhere cores or other direct techniques are not possible. The accuracy ofstrength estimate will be similar to that obtained by small cores but withconsiderable savings of time, expense and disruption.4.2.2.2 ESCOTThis test was proposed by Domone and Castro (118) in1987. Designed as adrilled-hole method, the test works on an expanding sleeve principle whichcauses internal fracture of the concrete at a depth of just under 20 mmbelow the surface, with a conical failure zone of between 100 and 200 mmdiameter. The test is much simpler than the Capo test, and although loadis applied by a torquemeter, no bearing ring is required as in the internalfracture test with load applied internally in a less concentrated manner.Laboratory correlations with compressive strength were shown to besimilar in nature but better than for the internal fracture test, and comparablein accuracy to the modified ASTM pull-out approach described inSection 4.2.1.2. Despite its potential advantages over the internal fracturetest, the method has not been subsequently developed.4.2.2.3 The Capo testThis has been developed in Denmark (1) as an equivalent to the Lok-testfor situations where use cannot be preplanned. The basic geometry of theLok-test described in Section 4.2.1.1 has been maintained, although thepull-out insert consists of an expanding ring inserted into an undercutgroove. The name is based on the expression ‘cut and pull-out’, and theprocedure consists of drilling a 45 mm deep, 18 mm diameter hole, afterwhich a 25 mm groove is cut at a depth of 25 mm using a portable millingmachine illustrated in Figure 4.22. The expanding ring insert is then placedand expanded in the groove, as shown in Figure 4.23, and conventionalLok-test pulling equipment can be used as described previously. Testingmust continue to pull out the plug of concrete, and the ring may be recovered,recompressed and re-used up to three or four times.Extensive laboratory testing programmes (107) have shown that thebehaviour of this test is effectively identical to the Lok-test and that thestrength calibration and reliability may be regarded as the same. It is claimed
110 Partially destructive strength testsFigure 4.22 Capo test equipment.Figure 4.23 Capo test configuration.that the entire testing operation, including drilling, may be completed inabout ten minutes, and the equipment is available in the form of a comprehensivekit. In Denmark this method has been accepted as equivalent tothe Lok-test and has been used on a number of projects for in-situ strengthdetermination in critical zones (1). The method is also covered by BS 1881:Part 207 and the new BS EN 12504-3. The potential areas of application are
Page 3 and 4:
Also available from Taylor & Franci
Page 5 and 6:
First published 1982by Surrey Unive
Page 7 and 8:
viContents2.3 Theory, calibration a
Page 9:
viiiContents7.5 Tests for freeze-th
Page 12 and 13:
Prefacexiwish to study particular m
Page 14 and 15:
Chapter 1Planning and interpretatio
Page 16 and 17:
Planning and interpretation of in-s
Page 18 and 19:
Page 20 and 21:
Page 22 and 23:
Page 24 and 25:
Page 26 and 27:
Page 28 and 29:
Page 30 and 31:
Page 32 and 33:
Page 34 and 35:
Page 36 and 37:
1.6 InterpretationPlanning and inte
Page 38 and 39:
Page 40 and 41:
Page 42 and 43:
Page 44 and 45:
Page 46 and 47:
Page 48 and 49:
Page 50 and 51:
Surface hardness methods 37Figure 2
Page 52 and 53:
Page 54 and 55:
Surface hardness methods 41influenc
Page 56 and 57:
Surface hardness methods 43cases ab
Page 58 and 59:
2.3.2 CalibrationSurface hardness m
Page 60 and 61:
Page 62 and 63:
Surface hardness methods 49(i) Conc
Page 64 and 65:
Chapter 3Ultrasonic pulse velocitym
Page 66 and 67:
Ultrasonic pulse velocity methods 5
Page 68 and 69:
Page 70 and 71:
Page 72 and 73: Ultrasonic pulse velocity methods 5
Page 94 and 95: 3.5 Reliability and limitationsUltr
Page 96 and 97: Partially destructive strength test
Page 104 and 105: 4.1.1.4 Reliability, limitations an
Page 134 and 135: Cores 121discussed in Chapter 1, re
Page 136 and 137: Figure 5.1 Core cutting drill.
Page 138 and 139: Cores 125of the location and size o
Page 140 and 141: Cores 127Figure 5.3 Point load test
Page 142 and 143: Cores 129Figure 5.4 Excess voidage
Page 144 and 145: Cores 131where r = bar diameter c
Page 146 and 147: Cores 133The strength differences b
Page 148 and 149: Cores 135from flexurally cracked te
Page 150 and 151: Cores 1371.0Ratio of measured core
Page 152 and 153: Cores 1393 applied to the 95% confi
Page 154 and 155: 6.1 In-situ load testingLoad testin
Page 156 and 157: Load testing and monitoring 143It w
Page 158 and 159: Load testing and monitoring 145Figu
Page 160 and 161: Figure 6.5 Test load on roof slab u
Page 162 and 163: Load testing and monitoring 149to e
Page 170 and 171: Load testing and monitoring 157Long
Page 172 and 173:
Load testing and monitoring 159Deve
Page 174 and 175:
Load testing and monitoring 161is t
Page 176 and 177:
Load testing and monitoring 163Ligh
Page 178 and 179:
Load testing and monitoring 165Tabl
Page 180 and 181:
Load testing and monitoring 167gaug
Page 182 and 183:
Load testing and monitoring 169(iii
Page 184 and 185:
Load testing and monitoring 171pref
Page 186 and 187:
Load testing and monitoring 173stra
Page 188 and 189:
Load testing and monitoring 17528Me
Page 190 and 191:
Durability tests 177DC electric cur
Page 192 and 193:
Durability tests 179the rate of cor
Page 194 and 195:
Durability tests 181Figure 7.5 Prof
Page 196 and 197:
Durability tests 183in detail to gi
Page 198 and 199:
Durability tests 185cement concrete
Page 200 and 201:
Durability tests 187Figure 7.11 Typ
Page 202 and 203:
Durability tests 189Figure 7.15 Whe
Page 204 and 205:
Durability tests 191concrete. Engin
Page 206 and 207:
Figure 7.18 Four-probe resistivity
Page 208 and 209:
Durability tests 195Although the pr
Page 210 and 211:
Durability tests 197(v) Evaluating
Page 212 and 213:
Area %10090807060504030201000Decrea
Page 214 and 215:
Durability tests 201Some studies ha
Page 216 and 217:
Durability tests 203It is well esta
Page 218 and 219:
Durability tests 205in which the wa
Page 220 and 221:
Durability tests 207Adsorbed layerL
Page 222 and 223:
Durability tests 209applied head an
Page 224 and 225:
Durability tests 211reading should
Page 226 and 227:
Durability tests 213Figure 7.30 Mod
Page 228 and 229:
Durability tests 215A water permeab
Page 230 and 231:
Durability tests 217types, strength
Page 232 and 233:
Durability tests 219at 105 ± 5 C
Page 234 and 235:
Durability tests 221although ultras
Page 236 and 237:
Chapter 8Performance and integrity
Page 238 and 239:
Performance and integrity tests 225
Page 240 and 241:
Page 242 and 243:
Page 244 and 245:
Page 246 and 247:
Page 248 and 249:
Page 250 and 251:
Page 252 and 253:
Page 254 and 255:
Page 256 and 257:
Page 258 and 259:
Page 260 and 261:
Page 262 and 263:
Page 264 and 265:
Page 266 and 267:
Page 268 and 269:
Figure 8.22 ‘Coma’ mini maturit
Page 270 and 271:
Page 272 and 273:
Page 274 and 275:
Chapter 9Chemical testing and allie
Page 276 and 277:
Chemical testing and allied techniq
Page 278 and 279:
Page 280 and 281:
Page 282 and 283:
Page 284 and 285:
Page 286 and 287:
Page 288 and 289:
Page 290 and 291:
Page 292 and 293:
Page 294 and 295:
Page 296 and 297:
Table 9.1 Comparison of chloride an
Page 298 and 299:
Page 300 and 301:
Page 302 and 303:
Page 304 and 305:
Page 306 and 307:
Page 308 and 309:
Appendix ATypical cases of test pla
Page 310 and 311:
Appendix A 297UPV: mean velocity =
Page 312 and 313:
Adopt estimated in-situ standard de
Page 314 and 315:
Appendix A 301without cores, it may
Page 316 and 317:
Appendix A 303(iii) ProposalsVisual
Page 318 and 319:
Appendix BExamples of pulse velocit
Page 320 and 321:
Appendix B 307Figure B3thusestimate
Page 322 and 323:
Appendix CExample of evaluation of
Page 324 and 325:
Appendix C 311Table C1No. of cores
Page 326 and 327:
References 31317 Carino, N.J. Nonde
Page 328 and 329:
References 31558 BS EN 12504-2 Test
Page 330 and 331:
References 31796 Nasser, K.W. and A
Page 332 and 333:
References 319134 Stoll, U.W. Compr
Page 334 and 335:
References 321175 Basheer, P.A.M.,
Page 336 and 337:
References 323209 Andrade, C. and M
Page 338 and 339:
References 325244 Kreijger, P.C. Th
Page 340 and 341:
References 327282 Bungey, J.H., Sha
Page 342 and 343:
References 329322 Tawhed, W. and Ga
Page 344 and 345:
References 331358 Jenkins, D.R. and
Page 346 and 347:
References 333399 Polivka, M., Kell
Page 348 and 349:
Index 335chemicalanalysis 6, 34, 12
Page 350 and 351:
Index 337optical fibres 162-3, 170o
Page 352 and 353:
Index 339water content 261, 263, 26
show all

Testing of Concrete in Structures: Fourth Edition

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?