settlement_of_shallow_foundations_on_granular_soils (Lutenegger ang DeGroot)

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The correlation between Kv and relative density, D, presented by Navfac is given in Figure5.10. To obtain an estimate of relative density from the SPT blowcount, the following equations,presented by Bazaraa (1967) are reco=ended:D, = [N/20(1 + 2p')jl 12D, = [N/20(3.25 + 0.5 p')] 112where:for p' ,;; 1.5 ksffor p' 1.5 ksf[5.68][5.69]D, =relative density (decimal)N =uncorrected blowcount at a depth of approximately D + B/2p' = effective overburden stress at a depth of D + B/2Alternatively, Navfac DM7.1 presented a chart for estimating relative density from blowcounts,shown in Figure 5 .11.5.2.18 Burland and Burbidge (1985)Burland and Burbidge (1985) presented another empirical method for using SPT results toestimate settlement offootings on granular soils. This method takes into account the load intensity,the shape of the footing and the depth of influence below the footing. It also considers whether thedeposit is normally consolidated or overconsolidated and is based on a reevaluation of nearly 200published case histories of observed settlements of various size footings.Settlements are calculated from the following expressions:s = 0.14 C,C 1 1c (B/B,) 0·7 (q'/a,) B, for NC soilss = 0.047 C,C 1 1, (B/B,) 0·7 (q'/a,) B, for OC soils and q',;; a',s = 0.14 C,C 1 1, (B/B,) 0·7 ((q'- 0.67 a',)/( a,)) for OC soils and q'> a',[5.70][5.71][5.72]where:s =settlement (in=)C, =shape of factorC 1 = depth of influence correction factorI, =soil compressibility indexB = footing width (in meters)B, =reference width= 0.3 mq' =net footing stress (in kPa)a, =reference stress= 100 kPaa',= preconsolidation stress (in kPa)81
~-~LU-LU~ eJ:.:t::\:!W~~k-----4-----+--~~ o:~ 5~-+~~~~~~~~~~-+---+~~"'~ 4~-&~~-H--~~~--+-~~-4~BOFigure 5.11 Navfac (1982) Correlation Between SPT Blowcount and Relative Density.82
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SETTLEMENT OF SHALLOW FOUNDATIONSON
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ACKNOWLEDGEMENTSThis study was fund
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5.2.6 Alpan (1964) ................
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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
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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
Page 41 and 42: " ~...,I...,"~~....."'w 0-~'z z1.0~
Page 43 and 44: 2 - Compute the settlement of one c
Page 45 and 46: s = settlementq = foundation stress
Page 47 and 48: 4.8 Wahls and Gupta (1994)A method
Page 49 and 50: Corrections to the SPT blowcount sh
Page 51 and 52: 4.9.1 Standard Penetration TestNume
Page 53 and 54: there are several techniques that h
Page 55 and 56: Overconsolidation ratio, OCRFigure
Page 57 and 58: Table 4.3 Soil Modulus from Standar
Page 59 and 60: Table 4.5 Soil Modulus from Cone Pe
Page 61 and 62: Table 4.5 Cont'dReference Relations
Page 63 and 64: Table 4.6 Other Expressions for Soi
Page 65 and 66: Table 5.1 Methods to Evaluate Settl
Page 67 and 68: 19. Stroud (1989)20. Berardi eta!.
Page 69 and 70: -100.-----~-----------------,~-----
Page 71 and 72: the compression of the layer is cal
Page 73 and 74: 20 40 60 dO 100Std. Penetration Res
Page 75 and 76: 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: I 2 3UNCONFINED COMPRESSIVE STRENGT
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 and 128: For different soils Menard suggeste
Page 129 and 130: 5.5 Dilatometer TestMarchetti (1980
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
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~N~~~~~~"' ~0.~100 1.0ii..., c. 10
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Table 5.9 Comparison of Settlement
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6.0 ALLOWABLE BEARING CAPACITY CHAR
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5lr)lr.tl\)J~2~'§ I~t--·/_'f()()/
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7\~' "'--O&nseVery Dense..___ N=5o-
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also noted that "If the pressure co
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6;:.:5~4~~ 3'~~ 2~~tl. I~~',I) 0(c!
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capacity is reduced, the allowable
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6.6 Sowers (1962)Sowers (1962) in L
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301-E~. (2-1 1 9)251-201-l\1050~1-"
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800700~- N'qo- 0.05 qo OOB 8~0_!:!.
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It was stated by Mohan et al. (1971
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1 4f--u.-(")1 2C IIVl'->- 1 0z!;;au
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600(a) D/B = 1 (b) D/B = 0.5 (c) D/
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6050z~- 40c:~0u~ 30/v----/0~ 20 ".0
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250----200 ,........15010050•/...
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q. = NJO.Ol2B (kN/m 2 ) [6.27)Equat
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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
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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
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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
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Parry, R.H.G., 1978. "Estimating Fo
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Schultze, E. and Sherif, G., 1973.
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Tucker, K.D., 1987. "Uplift Behavio
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settlement_of_shallow_foundations_on_granular_soils (Lutenegger ang DeGroot)

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