settlement_of_shallow_foundations_on_granular_soils (Lutenegger ang DeGroot)

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Soil TypeOverconsolidatedNormallyconsolidatedE,tfPIPeat Clay Silt SandSand andgravel• , • • • •E),t!Pl" E~t!PI " EM/Pi " E.,tfPI ">16 >14 2/3 >12 1/2 >10 1/39-16 2/3 8-14 1/2 7-12 1/3 6--10 l/4Weatheredand/or 7-9 1/2 1/2 1/3 1/4remouldedSlightly fracturedExtremelyRock Other or extremelyfracturedweathered"~ 1/3 "~ 1/2 "~ 2/3Figure 5.28 Values of factor f for Baguelin eta!. (1978).117
5.5 Dilatometer TestMarchetti (1980) suggested that the Dilatometer Modulus, En, could be used to estimate theone-dimensional constrained modulus, M 2 and provided an empirical approach to estimatingsettlement. This was also shown by Schmertmann (1981) to be a reasonable approach as evaluatingsoil stiffness.The DMT has proven especially useful for rapid and economical preliminary estimates ofsettlements of shallow foundations and has been used in a number of different soils as summarizedin Table 5.8. Each DMT produces a predicted modulus value at a particular point in the foundationsoil, and at the particular effective stress condition existing at that point at that tirue. The engineercan calculate this condition by computing total vertical overburden pressure and the equilibriumwater pressure at each point. All soil modulus values are effective stress dependent to varyingdegrees on vertical and horiwntal pre-stress magnitudes, cementation, etc. In some problems it maybe advisable to adjust the DMT -determined modulus values to better match the vertical stresschanges imposed by the structure involved during its construction and service life as outlined bySchmertmann (1986).ITable 5.8 Reported Use of Dilatometer For SettlementPredictions of Shallow FoundationsFoundationISoil TypeIReferencemisc. miSC. Hayes (1986)miSC. miSC. Schmertmann (1986)misc. miSC. Saye & Lutenegger (1988)misc. residual Mayne & Frost (1991)0.9mx 0.9m Sand Skiles & Townsend (1994)I5.5.1 Schmertmann (1986)Schmertmann (1986) recommended a procedure to estimate footing settlements based on thework by Janbu (1963, 1985) in which it was pointed out that among other things, using a siruplemodulus concept could significantly simplify the understanding and calculation of consolidationsettlements. Janbu suggested using the following equation of calculate consolidation settlement:where:[5.112]118
Page 1 and 2:
SETTLEMENT OF SHALLOW FOUNDATIONSON
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ACKNOWLEDGEMENTSThis study was fund
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5.2.6 Alpan (1964) ................
Page 7 and 8:
LIST OF TABLESTable 2.1 Previous In
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Figure 5.9 Schultze and Sherif(l973
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Figure B.8 Updated Douglas Chart (O
Page 13 and 14:
2.0 BACKGROUND - SETTLEMENT OF SHAL
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HORIZONTAL DISPLACEMENT, mm10. 0Not
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3.1 Introduction3.0 DESIGN APPROACH
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4.0 ELASTIC SOLUTIONS FOR ESTIMATIN
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"o2.8-2.4t2.01.61.2(a)iII-~10520.80
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- 0 2:::::>0a::- (!)-Q.1.5 H.......
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2.52.0fl-1 1.5Figure 4.5 Janbu et a
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thus underestimate settlement. A co
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1.00.9 ~--~~~ ~t::$:::"--+-----+---
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1.0~'-o0.90.80.70.60.5~~~-BURLAND\~
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settlement of each layer. The layer
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ifa.=JO" S=Q867xplbxC 80 02 .Cs04 0
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0. I 00. 150.20m'-.NJ:>-~w0w>....<-
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I2IIfvEDG~- ~,..=.33~vc/-""CENTERJL
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" ~...,I...,"~~....."'w 0-~'z z1.0~
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2 - Compute the settlement of one c
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s = settlementq = foundation stress
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4.8 Wahls and Gupta (1994)A method
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Corrections to the SPT blowcount sh
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4.9.1 Standard Penetration TestNume
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there are several techniques that h
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Overconsolidation ratio, OCRFigure
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Table 4.3 Soil Modulus from Standar
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Table 4.5 Soil Modulus from Cone Pe
Page 61 and 62:
Table 4.5 Cont'dReference Relations
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Table 4.6 Other Expressions for Soi
Page 65 and 66:
Table 5.1 Methods to Evaluate Settl
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19. Stroud (1989)20. Berardi eta!.
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-100.-----~-----------------,~-----
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the compression of the layer is cal
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20 40 60 dO 100Std. Penetration Res
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40 60 80 100RELATIVE DENSITY, PER C
Page 77 and 78: VIa..LLI0::JVIS P T- NUMBERS OF BLO
Page 79 and 80: Alp an suggested that the correctio
Page 81 and 82: y = soil total unit weightCw = wate
Page 83 and 84: 1000~-------r----~~--------~-------
Page 85 and 86: 00 0·5 1·0 1·5·Ye2•0Figure 5,
Page 87 and 88: s M~87 !1•D.U/B)p~<=::!::':'"'e11
Page 89 and 90: N = uncorrected blowcountC, = embed
Page 91 and 92: I 2 3UNCONFINED COMPRESSIVE STRENGT
Page 93 and 94: ~-~LU-LU~ eJ:.:t::\:!W~~k-----4----
Page 95 and 96: 5.2.19 Stroud (1989)Stroud (1989) s
Page 97 and 98: 'E-z~161412 J-100WIZI.D8 J-4 J- 1jz
Page 99 and 100: N)'Nq140 IIIN'YINcIIII20 80 I/N'Y 1
Page 101 and 102: The soil stiffness is evaluated usi
Page 103 and 104: 1 •••. ... .,1-: •. .......
Page 105 and 106: 5.2.21 Anagnostopoulos eta!. (1991)
Page 107 and 108: Ll.p' = (2P cos 6 8)/rcz 2 [5.91]Ad
Page 109 and 110: 0~·Illso ·~100 II~\~ 0••100 "
Page 111 and 112: 5.3.5 Schmertmann (1970)In what may
Page 113 and 114: 4.- Use Equation 5.95 to calculate
Page 115 and 116: Soil Type.QJNsandy silt 2.5sand & g
Page 117 and 118: IOr---.----,,---,---,,,---,---,----
Page 119 and 120: Table 5.5 Influence Factors for Ber
Page 121 and 122: Table 5.6 Reported Use ofPressureme
Page 123 and 124: q' =net footing pressureB = footing
Page 125 and 126: In order to recognize the strain ar
Page 127: For different soils Menard suggeste
Page 131 and 132: Method B - Special MethodThis metho
Page 133 and 134: OCR= [K(OC)/(1-sin ~ )](1 10·' sin
Page 135 and 136: Figure 5.29 Settlement Ratio as a f
Page 137 and 138: 5.6.2 Barata (1973)B arata also poi
Page 139 and 140: 6"';_;51 v = o , 1~ c~ 4 o/:;0-~ "'
Page 141 and 142: and circular foundation; 4B for str
Page 143 and 144: ~N~~~~~~"' ~0.~100 1.0ii..., c. 10
Page 145 and 146: Table 5.9 Comparison of Settlement
Page 147 and 148: 6.0 ALLOWABLE BEARING CAPACITY CHAR
Page 149 and 150: 5lr)lr.tl\)J~2~'§ I~t--·/_'f()()/
Page 151 and 152: 7\~' "'--O&nseVery Dense..___ N=5o-
Page 153 and 154: also noted that "If the pressure co
Page 155 and 156: 6;:.:5~4~~ 3'~~ 2~~tl. I~~',I) 0(c!
Page 157 and 158: capacity is reduced, the allowable
Page 159 and 160: 6.6 Sowers (1962)Sowers (1962) in L
Page 161 and 162: 301-E~. (2-1 1 9)251-201-l\1050~1-"
Page 163 and 164: 800700~- N'qo- 0.05 qo OOB 8~0_!:!.
Page 165 and 166: It was stated by Mohan et al. (1971
Page 167 and 168: 1 4f--u.-(")1 2C IIVl'->- 1 0z!;;au
Page 169 and 170: 600(a) D/B = 1 (b) D/B = 0.5 (c) D/
Page 171 and 172: 6050z~- 40c:~0u~ 30/v----/0~ 20 ".0
Page 173 and 174: 250----200 ,........15010050•/...
Page 175 and 176: q. = NJO.Ol2B (kN/m 2 ) [6.27)Equat
Page 177 and 178: fl(m)6 600~N.:::~~"2 ~~M"5 500-~~4
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0 2 4B,FT10 12Qo =ALLOWABLE BEARING
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0 0 010c"' E~-V> "' 8.£~0-V>drr!'?
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Table 6.2 (continuted)Method lxlm 1
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7.0 LOAD-SETTLEMENT BEHAVIOR OF SPR
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The value of Q/Q, 1 , is essentiall
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Figure 7.3 Nondimensional Load-Sett
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120~-------------------------------
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z00 0.7:5w 0.6f- <t~ 0.5~:::J 0.4--
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qb(s/0=5%)0.5 1.0 150~6-....2"~zUJ
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tDr= 59%q'YB0 20 40 6040 t,-Dr= 47%
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The bearing capacity factors are a
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7.3 Review of Load TestsInitially,
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Table 7.2 Normalized Load-Settlemen
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Table 7.3 Normalized Load - Settlem
Page 207 and 208:
Table 7.4 Normalized Load- Settleme
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0.9* •+.•t * ' '........... ,
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1.0'I' i 'I' i0.9~"' i "'v :'I' "'
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8.0 SETTLEMENTS FROM CYCLIC LOADING
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9.0 RECOMMENDATIONSBased on the res
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4- Martin (1987) Method (PMT)5- Par
Page 219 and 220:
Berardi, R., Jamiolkowski, M., and
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Engineering." Proceedings of the 2n
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Garga, V.K., and Quin, J.T., 1974.
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Kovacs, W.D., Evans, J.C. and Griff
Page 227 and 228:
Meigh, A.C., 1963. "Discussion on S
Page 229 and 230:
Parry, R.H.G., 1978. "Estimating Fo
Page 231 and 232:
Schultze, E. and Sherif, G., 1973.
Page 233:
Tucker, K.D., 1987. "Uplift Behavio
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settlement_of_shallow_foundations_on_granular_soils (Lutenegger ang DeGroot)

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