a

• AASHTO allowable stress design (ASD) method 276–283
  • design example 283–287
  • design procedure 277–283
  • forces on reinforce soil mass 278
• active‐and‐earthquake coefficient 104
• apparent cohesion
  • apparent cohesion equation, Wu‐Pham 141, Eqn. (3‐6)
  • conventional equation 140, Eqns. (3‐1) to (3‐4)
  • definition 137–142
  • in terms of Mohr circles 138–139
  • strength envelope 138–139
  • validity of conventional equation 140–141, 242–246
• apparent confining pressure
  • apparent confining pressure equation, Wu‐Pham 141, Eqn. (3‐5)
  • definition 140
  • in terms of Mohr circles 138–139
• articulated panel facing GRS wall 171
• ASTM D4595 192–193
• ASTM D6637 192–193
• at‐rest earth pressure
  • correlations 61–62
  • definition 60
  • values, suggested 63

b

• backfill material and placement
  • fill compaction 387–388
  • free‐draining backfill 386
  • material criteria 386–387
• bearing capacity of foundation soil
  • bearing capacity factors 322–323
  • Meyerhof equation 322–323, Eqn. (5‐44)
• bin pressure
  • applicability 257
  • concept 257–258
• Boussinesq solution 78–79
• bridge abutment (see NCHRP design method)
• bridge bumps 149, 298
• bridge sill 290

c

• cast‐in‐place full‐height facing GRS wall
  • before & after seismic event 163
  • completed wall photos 162
  • construction photos 162
  • construction sequence 160–161
  • cross section, typical 152, 161
  • earthquake resistance 163–164
  • RRR (reinforced railroad/road with rigid facing) 160–164

• CMU (Concrete Masonry Units)
  • costs 159–160
  • description 159
  • types 159
• compaction‐induced stress (CIS) 116–117, 146–147
• compound failure 233–234
• concrete block facing
  • concrete leveling pad 161, 331, 389
  • sand‐gravel pad 331, 366–367, 386, 389
  • tolerance 390
• concrete block GRS wall
  • advantages and disadvantages 160, 175–176
  • CMU (Concrete Masonry Units) face 159
  • completed wall photos 157–158
  • cross‐section, typical 386
  • deterioration 175–176
  • efflorescence 175–176
  • SRW (Segmental Retaining Wall) face 159
• concrete block GRS wall, construction
  • completed wall photos 157–158
  • concrete footer 368
  • construction photos 369
  • construction sequence 367
  • corners 368, 387, 389
  • cross‐section, typical 386
  • CTI tails 168, 324, 368, 370, 376, 380, 385–386
  • curved face 158, 389
  • facing batter 159, 160, 290, 326–328, 331, 368, 389, 390, 391
• cone penetration test (CPT)
  • correlations 34–35
  • test method 33
• confined load–deformation tests, geosynthetics
  • intrinsic confined test 198
  • pressure‐sensitive geosynthetics 198
  • soil‐confined test 198
• connection force equations
  • equations 258–259, Eqns. (5‐12) to (5‐15)
  • observations from equations 259–261
• connection stability, concrete block facing 233, 255–261
• constrained fill zone 109, 262–266
• Coulomb active analysis
  • analytical solution 86–88, Eqns. (2‐15) & (2‐16)
  • external load on crest 85
  • graphical solution 84–86
• Coulomb analysis
  • Coulomb active analysis 84–91
  • Coulomb analysis with seismic force 102–107
  • Coulomb passive analysis 91–93
  • forces on failure plane at failure 84
  • influence of seepage 94–100
  • Influence of submergence 93–94
  • relative wall movement 100–102
  • soil–wall friction angle 108
• Coulomb passive analysis
  • analytical solution 93, Eqns. (2‐17) & (2‐18)
  • graphical solution 91–92
• creep, GRS
  • design protocol 211
  • field behavior 209
  • finite element analysis 209–210

• curved Mohr–Coulomb failure envelopes 37–42

d

• design, GRS vs. GMSE 232–235
• design methods, GMSE
  • comparison of design reinforcement layouts 236–240
  • earth pressure approach 235–236
  • slope stability approach 235
• direct shear test
  • interpretation of test data 16–17
  • φ_peaks vs. φ_residual 17, 18
• drainage, GRS walls 392
  • geocomposite drainage strips 393
• drained strength of clays
  • applicable conditions 49–50
  • determination 49–54
  • excavation in clay 50–51
  • excavation vs. embankment 50–52
  • non‐durable geomaterials 50
  • rise in free water level 49–50
• ductility strain, geosynthetics 245

e

• eccentricity vs. overturning failure, GRS 317, 320
• effective stress 13
• efflorescence 175–176
• elevated temperature, creep (see SGIP test)
• equivalent fluid density 113–116
• excavation in clay 50–51
• external stability, GRS
  • base sliding failure 233–234, 317, 319, 320–321
  • bearing failure 233–234, 322–323
  • eccentricity/lift‐off failure 232–235, 317, 321–322
  • overall slope failure 233–235, 329–330
  • overturning failure 233–235, 317, 320

f

• facing failure 233
• facing, GRS wall construction
  • concrete block facing 366–368, 388–390
  • natural rock facing 392
  • precast full‐height panel facing 376–379, 390–391
  • timber facing 380–383, 391
  • wrapped‐face geotextile facing 371–376, 390
• facing rigidity 250, 255
• failure of GMSE, causes 240–241
• field‐scale experiments, GRS 129–136
• finite element analysis, GRS 148, 201, 219
• flexible retaining walls 110–111
• frost penetration depth 113
• full‐height precast panel facing GRS wall
  • advantages 165
  • attributes 164, 377
  • completed wall photo 167
  • construction photos 166, 379
  • construction sequence 378
  • cross‐section, typical 164, 376
  • flexible connection 164, 377
  • IFF (independent full‐height facing) 164–166
• functions, geosynthetics
  • containment of soil or liquid 182
  • drainage 182
  • filtration 182
  • reinforcing 182
  • separation 182

g

• gabion facing GRS wall 173
• geocell mattress 188–189
• geocells 188–189
• geocomposites 189–190
• geogrids
  • biaxial 187–188
  • flexible geogrids 187–188
  • stiff geogrids 187–188
  • triaxial 187–188
  • uniaxial 187–188
• geosynthetic inclusion (see geosynthetic reinforcement)
• geosynthetic reinforcement
  • advantages and disadvantages 224–225
  • creep 201–204
  • definition 181
  • drainage 223–224
  • filtration 223–224
  • half‐lives 181
  • history 181
  • load–deformation behavior 191–201
  • load–deformation test, confined in soil 197–199
  • load–deformation test, pressure‐confined 198–199
  • load–deformation test, unconfined 191–197
  • load–deformation–time relationship 211–214
  • orientation, placement 384–385
  • overlapping, placement 194, 384
  • secant modulus 200–201
  • soil–geosynthetic interface bonding 218–223
  • stress relaxation 211–218
  • synergistic effect 182
  • types 182
• geosynthetic reinforcement placement, construction 384–386
• geosynthetics
  • costs 191
  • definition 181
  • description 190
  • functions 182–183
  • global market 181
  • types 182
• geotextile fibers
  • filaments 183
  • silt films 184
  • staple fibers 183–184
• geotextiles
  • geotextile fibers 183–184
  • knitted geotextiles 187
  • nonwoven geotextiles 184–187
  • woven geotextiles 184–185
• GMSE ix–x, 123
• GRS ix–x, 123–127
• GRS walls 152–173
  • advantages & disadvantages 128–129
  • common types 152
• GRS‐IBS 142, 240
• GRS‐NLB 314–332

i

• interface pullout formula
  • applied pullout force, determination 222
  • coefficient of friction, determination 222
  • displacements along reinforcement, determination 222–223
  • formula 220, Eqn. (4‐1)
• internal stability, GRS
  • embedment requirement 330–331
  • facing connection requirement 331–332
  • reinforcement length requirements 235, 246, 249, 265–266, 329
  • reinforcement stiffness requirement 242–246, 324
  • reinforcement strength and ductility requirements 242–246, 325
  • spacing requirement 126, 240
• internally stabilized soil wall 123–124

l

• lateral earth pressure (due to surcharge)
  • diagrams 78–79
  • examples 274–275
• lateral earth pressure, GRS walls
  • bin pressure 257–258
  • example profiles 256–257
  • vs. lateral soil stress 255–256
• lateral movement, wall face
  • general methods 249–250
  • Wu‐Pham lateral movement model 250–252
• limiting equilibrium analysis 64
• load‐carrying capacity, GRS
  • comparison with conventional equation 245–246
  • comparisons with measured data 142, 242–247
  • conventional equation 140, Eqn. (3‐4)
  • load‐carrying capacity equation, Wu‐Pham 141–142, Eqn. (3‐7), 243, Eqn. (5‐2)
  • W‐factor, the 141
• load–deformation behavior, geosynthetics
  • aspect ratio effect 194–195
  • load–deformation relationships, typical 194–195
  • strain rate effect 196
  • temperature effect 196–197
• load–deformation–time relationship, geosynthetics
  • conversion of curves 212–214
  • creep curve 211–212
  • isochronous curve 211–212
  • relaxation curve 211–212, 214–216
• long‐term reduction factors, AASHTO
  • creep 253–254
  • installation damage 253
  • long‐term degradation 253
• long‐term strength, geosynthetics
  • AASHTO equation 252, Eqn. (5‐11)
  • ductility and long‐term factor F_dl 255
  • long‐term design strength, recommended 254–255
  • reduction factors 252

m

• maximum soil particle size, GRS 243, 244
• mechanical property tests, geosynthetics
  • creep tests, confined 203–204
  • load–deformation tests, confined 197–199
  • load–deformation tests, unconfined 191–197
  • pullout tests 218–221
  • Soil–Geosynthetic Interactive Performance (SGIP) test 204–209
• mini pier experiments, GRS 129–131
• Minimum Average Roll Value (MARV) 252, 325, 336, 344, 354
• Mohr circle of stress 4–7
  • pole of Mohr circle 7–13
  • sign convention 6–7
• Mohr–Coulomb failure criterion
  • failure envelope 14–15
  • in terms of effective stress 14–15, Eqn. (1‐6)
  • in terms of principal stress 15, Eqns. (1‐7) & (1‐8)
  • in terms of total stress 14, Eqn. (1‐5)
  • stresses on failure plane at failure 14
• Mohr–Coulomb strength parameters 14–16, 21–22, 37–38, 50, 119, 329
• Mononobe–Okabe analysis 102–105

n

• NCHRP design method (for GRS bridge abutments) 287–314
  • angular distortion 298
  • bearing pressure, allowable 288, 291–293
  • bridge abutment 287–314
  • correction factor for sill width 291–292
  • design example 298–314
  • design procedure 288–298
  • integrated sill 290
  • isolated sill 290
  • required conditions 288
• NCHRP test abutments 293
• non‐durable geomaterials 50
• non‐load bearing (GRS‐NLB) GRS walls 314–358
  • bearing failure 322–323
  • broken crest 317, 319
  • connection strength 331–332
  • design examples 332–358
  • design procedure 316–332
  • ductility of geosynthetic reinforcement 325
  • eccentricity/lift‐off failure 317, 320, 321–322
  • embedment 330–331
  • facing batter 331
  • facing requirements 330–332
  • lateral sliding failure 319, 320–321
  • level crest and sloping crest 317–318
  • required conditions 314–315
  • rotational slide‐out failure 329–330
  • stiffness of geosynthetic reinforcement 324
• nonwoven geotextiles
  • heat bounded 184–186
  • needle punched 184–186
  • resin bounded 184–186

p

• permittivity
  • definition 223
  • determination 224
• plane strain test
  • plane strain condition 28
  • plane strain vs. triaxial 28
  • side wall lubrication 28–29
  • test setup 28–29
• plate load test
  • load‐settlement relationships of non‐prestressed sands 36
  • test method 35
• pole of Mohr circle
  • definition 7
  • examples 8–13
  • how to locate 7–8
• polyester (PET) 183–184, 191, 196, 201, 211
• polyethylene (PE) 183–184, 191, 196, 201, 211
• polypropylene (PP) 183–184, 187, 191, 201, 211
• porewater pressure dissipation, GRS 149–151
• potential failure modes, GMSE & GRS
  • compound failure 233–234
  • external stability, GRS 232–235
  • facing stability 233, 255–261
  • internal stability, GMSE 232–235
  • internal stability, GRS (see internal stability, GRS)
• precast full‐height panel facing GRS wall (see full‐height precast panel facing GRS wall)
• pullout failure 232, 246–249
• pullout stability, group
  • evaluation methods 232, 246–249
  • rule of three 248–249
  • safety factor, a single layer 247, Eqn. (5‐5)
  • safety factor, group 248–249, Eqns. (5‐6) to (5‐8)

r

• Rankine active analysis
  • coefficient of active earth pressure, K_A 68
  • development, Mohr circles 64–65
  • failure surfaces 72–74
  • mathematical solution 66–68
  • walls of inclined backface 70–72
• Rankine analysis
  • assumptions 80–82
  • external loads on crest 78–80
  • inclined crest 73–74
  • inclined crest with inclined surcharge 74–77
  • inclined surcharge 73–74
  • influence of submergence 77–78
  • magnitude of wall movement 81
  • modes of wall movement 81–82
  • Rankine active analysis 64–65
  • Rankine passive analysis 65–66
  • relative soil–wall movement, implied 72
• Rankine passive analysis
  • coefficient of passive earth pressure, K_P 68
  • development, Mohr circles 65–66
  • failure surfaces 72–74
  • mathematical solution 66–68
• Rankine vs. Coulomb analysis
  • applicability 109–110
  • comparison 107–109
• reduced‐scale experiments, GRS 146
• reinforcing mechanisms, GRS 136–151
  • apparent cohesion 137–142
  • apparent confining pressure 137–142
  • compaction‐induced stress, increase 146–147
  • lateral deformation, restrain 148
  • pore water pressure dissipation, accelerate 149–151
  • potential failure wedge, stabilize 148–149
  • soil ductility, improve 150–151
  • soil integrity, preserve 149–150
  • suppression of soil dilation 143–146
• reinforced soil 123–127
  • stress distribution 126–127
  • triaxial test behavior 125
• reinforced soil foundation (RSF) 295, 330
• reinforcement length, minimum
  • GRS walls 233–235, 265–266
  • minimum lengths, various design guides 261
  • research and case histories 262–265
  • truncated base walls 261, 264–265, 266, 294, 317, 320, 348–358, 385
• reinforcement loads, determination
  • isochronous curves 216–218
  • isotach model 216–218
  • load–deformation relationship 216–218
• reinforcement spacing
  • typical ix–x, 126, 240
  • vs. reinforcement strength, GRS 242–246
• reinforcement stiffness, GRS 242–246
• reinforcement strength, GRS
  • conventional equation 242, Eqn. (5‐1)
  • reinforcement strength equation, Wu‐Pham 244–245, Eqns. (5‐3) & (5‐4)
• relative soil–wall movement, Coulomb analysis
  • negative‐δ case 100–102
  • positive‐δ case 100–102
• retained earth 283
• rigid retaining walls
  • compaction‐induced stress 116–117
  • design chart, NAVFAC 114–115
  • drainage, common measures 94–95
  • equivalent fluid density 113–116
  • proportions, common 112
  • shear strength parameters 119
  • stability evaluation 117–119
  • types 110–111
• rise in free water level in clay 49–50
• rock facing GRS wall 170

s

• secant angle of friction 38, 39–42
• seepage, Coulomb analysis
  • chart for walls with a vertical drain 97–98
  • fundamental force diagram 96–97
  • inclined drain 97–98
  • vertical drain 97–100
• seismic effect, Coulomb analysis 102–107
  • design example 105–107
  • Mononobe‐Okabe earthquake coefficients 102–105, Eqns. (2‐19) to (2‐23)
  • seismic coefficient of acceleration 105
• sequence of construction with rigid facing 376, 393
• serviceability stiffness, GRS (see reinforcement stiffness, GRS)
• SGIP test
  • elevated temperature, creep 205–207
  • general concept 204–205
  • modified SGIP test 207–208
  • test procedure 205
  • unique features 209
• shear strength of cohesionless soil 37–43
  • curved failure envelope for c=0 40–41
  • curved failure envelope for c≠0 41–42
  • p‐q diagram 38–39
  • strength values, ϕ', typical 43
  • test data, interpretation 37–42
• shear strength of cohesive soil 43–55
  • compacted clay 44
  • determination, undrained strength of clay 43–45
  • drained strength of clays 49–50
  • empirical correlations, undrained strength 45–47
  • stiff clay 54–55
  • undrained shear strength of clays 43–49
  • variation with depth, undrained strength 47–49
• shear strength of silts 55
• shear strength tests
  • cone penetration test (CPT) 33–35
  • direct shear test 16–17
  • plane strain test 28–29
  • plate load test 35–37
  • standard penetration test (SPT) 30–33
  • triaxial test 17–27
  • vane shear test 29–30
• site and foundation preparation, construction 383–384
• soil dilation, suppression
  • dilation angle, ψ 145
  • effects 143–144
  • influence of reinforcement spacing 145
  • measured behavior 144–145
  • measured behavior from reduced‐scale tests 146
• soil wall (see internally stabilized soil wall)
• soil–geosynthetic composites (SGC) 132–136, 232–235
  • ductility and long‐term factor (F_dl) 245, 255
  • experiments, field‐scale 132–134
  • load‐carrying capacity 242–243
  • measured behavior from experiments 135–136
  • reinforcement design parameters 243
  • reinforcement stiffness, required 243–244
  • reinforcement strength, required 244–245
  • specimen size 133–134
• soil–geosynthetic interface tests
  • applications of test methods 219–220
  • direct shear interface test 218–220
  • pullout test 218–220
  • test methods 218–221
  • types of direct shear interface test 221
• soil–reinforcement interaction (see SGIP test)
• soil–wall interface friction angle and adhesion, typical values 108
• Specifier's Guide, geosynthetics 200–201
• SRW (Segmental Retaining Wall) units
  • costs 159–160
  • description 159
  • types 159
• standard penetration test (SPT)
  • blow count N and standardized N₆₀ 31–33
  • correlations 31–32
  • test method 30–31
• steepened slope 59
• stress at point
  • Cauchy Formula 3–5, Eqn. (1‐2)
  • Mohr circle of stress 6–7
  • pole of Mohr circle 7–13
  • stress tensor 4–5
  • stress vector 2–3
• stress relaxation, geosynthetics
  • definition 211
  • full‐scale experiment 214–217
• synthetic polymers, geosynthetics
  • general behavior 183
  • types 183

t

• tiebacks, quasi 232–235, 236
• timber facing GRS wall
  • advantages and disadvantages 176–177
  • cross‐section, typical 152, 381
  • Denver test wall, the 168–169, 236–237
  • facing detail 168
• timber facing GRS wall, construction
  • completed wall photos 167, 383
  • construction photos 382
  • construction sequence 381
• tire facing GRS wall 172
• transmissivity
  • definition 223
  • determination 224
• triaxial test
  • drainage conditions 21
  • influence of soil initial state 24–26
  • loading paths 26–27
  • strength envelopes, idealized 24–25
  • test setup 19
  • two stages 18–20
  • σ‐ε relationship, typical 20–21
• truncated base walls (see reinforcement length, minimum)

u

• unconfined compression experiments, GRS 129–130, 131–132
• unconfined load–deformation tests, geosynthetics
  • biaxial test 191–192
  • grab tensile test 191–192
  • plane strain test 191–192
  • wide‐width tensile test 191–194
• U.S. Forest Service (USFS) design method
  • design example 271–276
  • design procedure 266–271

w

• wedge analysis (see Coulomb analysis)
• welded wire mesh facing GRS wall 172
• Westergaard solution 80
• W‐factor, the 141
• wheel loading 273
• wick drain 281, 298
• woven geotextiles
  • fibrillated yarn 184
  • monofilament yarn 184, 185
  • multifilament yarn 184, 185
  • silt film yarn 184, 185
  • spun yarn 184
• wrapped‐face GRS wall
  • advantages and disadvantages 173–175
  • bed‐sheet wall, the 173–174
  • completed wall photos 153–154
  • experiences with 156
  • geotextile wrapped‐face walls 153–154, 371–373
  • shotcrete face 154, 372–373
  • vegetated face 155
  • wire‐mesh wrapped‐face walls 153–154, 374–376
• wrapped‐faced GRS wall, construction
  • completed wall photos 153–155
  • construction photos 370–371
  • construction sequence 372, 375
  • cross‐section, typical 372, 375