settlement_of_shallow_foundations_on_granular_soils (Lutenegger ang DeGroot)

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results are available immediately at the end of the test boring and may be used immediately in theanalysis. The test is considered applicable for the majority of granular soil deposits in theCommonwealth.A typical site investigation at a single bridge pier or abutment location at a site might be asfollows:1- Four (4) SPT boring with continuous SPT's conducted throughoutthe anticipated zone of influence of the foundation.2- Four (4) DCT profiles conducted continuously from the ground surfaceto the anticipated depth of influence of the foundation.3- Two (2) pressuremeter borings with six to eight (6 to 8) PMT'sperformed in each boring;orTwo (2) plate load tests conducted on a 1 ft. square rigid plate at theanticipated depth of the foundation.This proposed site investigation appears to represent a significant commitment of time, resources,and cost, however, it is estimated that this work could be performed in two working days with a crewof two drillers (driller & helper) and two technicians. There is no doubt that such an investigationrepresents an increase in overall cost of the site investigation however, as previously indicated theoverall cost savings, averaged out over a complete project, is considered to be siginficant.9.2 Improvements in Settlement AnalysisSerious consideration should be given to adapting more advanced and appropriate methodsof predicting settlements based on the discussions presented in Section 5 of this report. Preferenceshould be given to those techniques which recognize the variation is stiffness parameters withincreasing levels of stress and strain and which recognize that the deformation behavior of granularsoil is intimately linked to the ultimate bearing capacity. Modifications to the elastic approach ofcalculating settlements appear to be the most desirable. Methods which are almost entirely basedon empirical observations between penetration resistance and measured settlements have limitedappeal and should generally be discontinued unless a study is undertaken to establish correlationsfor specific geologic deposits in a relatively limited geographic area.The following settlement methods are generally considered to have the highest probabilityof success:1- Stroud (1989) Method (SPT)2- Wahls and Gupta (1994) Method (SPT)3- Menard and Rousseau (1962) Method (PMT)205
4- Martin (1987) Method (PMT)5- Parry (1978) Method (PLT)In addition, initial, preliminary estimates of settlement should be made using the upper-bond generalload-settlement relationship developed as a part of this project and described in Section 7 forappropriately sized footings and by using the extrapolation approach summarized by Burland eta!.(1977).206
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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) ................
Page 7 and 8:
LIST OF TABLESTable 2.1 Previous In
Page 9 and 10:
Figure 5.9 Schultze and Sherif(l973
Page 11 and 12:
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
Page 17 and 18:
3.1 Introduction3.0 DESIGN APPROACH
Page 19 and 20:
4.0 ELASTIC SOLUTIONS FOR ESTIMATIN
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"o2.8-2.4t2.01.61.2(a)iII-~10520.80
Page 23 and 24:
- 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
Page 63 and 64:
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
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VIa..LLI0::JVIS P T- NUMBERS OF BLO
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Alp an suggested that the correctio
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y = soil total unit weightCw = wate
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1000~-------r----~~--------~-------
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00 0·5 1·0 1·5·Ye2•0Figure 5,
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s M~87 !1•D.U/B)p~<=::!::':'"'e11
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N = uncorrected blowcountC, = embed
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I 2 3UNCONFINED COMPRESSIVE STRENGT
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~-~LU-LU~ eJ:.:t::\:!W~~k-----4----
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5.2.19 Stroud (1989)Stroud (1989) s
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'E-z~161412 J-100WIZI.D8 J-4 J- 1jz
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N)'Nq140 IIIN'YINcIIII20 80 I/N'Y 1
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The soil stiffness is evaluated usi
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1 •••. ... .,1-: •. .......
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5.2.21 Anagnostopoulos eta!. (1991)
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Ll.p' = (2P cos 6 8)/rcz 2 [5.91]Ad
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0~·Illso ·~100 II~\~ 0••100 "
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5.3.5 Schmertmann (1970)In what may
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4.- Use Equation 5.95 to calculate
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Soil Type.QJNsandy silt 2.5sand & g
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IOr---.----,,---,---,,,---,---,----
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Table 5.5 Influence Factors for Ber
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Table 5.6 Reported Use ofPressureme
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q' =net footing pressureB = footing
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In order to recognize the strain ar
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For different soils Menard suggeste
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5.5 Dilatometer TestMarchetti (1980
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Method B - Special MethodThis metho
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OCR= [K(OC)/(1-sin ~ )](1 10·' sin
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Figure 5.29 Settlement Ratio as a f
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5.6.2 Barata (1973)B arata also poi
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6"';_;51 v = o , 1~ c~ 4 o/:;0-~ "'
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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
Page 149 and 150:
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
Page 161 and 162:
301-E~. (2-1 1 9)251-201-l\1050~1-"
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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
Page 179 and 180: 0 2 4B,FT10 12Qo =ALLOWABLE BEARING
Page 181 and 182: 0 0 010c"' E~-V> "' 8.£~0-V>drr!'?
Page 183 and 184: Table 6.2 (continuted)Method lxlm 1
Page 185 and 186: 7.0 LOAD-SETTLEMENT BEHAVIOR OF SPR
Page 187 and 188: The value of Q/Q, 1 , is essentiall
Page 189 and 190: Figure 7.3 Nondimensional Load-Sett
Page 191 and 192: 120~-------------------------------
Page 193 and 194: z00 0.7:5w 0.6f- <t~ 0.5~:::J 0.4--
Page 195 and 196: qb(s/0=5%)0.5 1.0 150~6-....2"~zUJ
Page 197 and 198: tDr= 59%q'YB0 20 40 6040 t,-Dr= 47%
Page 199 and 200: The bearing capacity factors are a
Page 201 and 202: 7.3 Review of Load TestsInitially,
Page 203 and 204: Table 7.2 Normalized Load-Settlemen
Page 205 and 206: Table 7.3 Normalized Load - Settlem
Page 207 and 208: Table 7.4 Normalized Load- Settleme
Page 209 and 210: 0.9* •+.•t * ' '........... ,
Page 211 and 212: 1.0'I' i 'I' i0.9~"' i "'v :'I' "'
Page 213 and 214: 8.0 SETTLEMENTS FROM CYCLIC LOADING
Page 215: 9.0 RECOMMENDATIONSBased on the res
Page 219 and 220: Berardi, R., Jamiolkowski, M., and
Page 221 and 222: Engineering." Proceedings of the 2n
Page 223 and 224: Garga, V.K., and Quin, J.T., 1974.
Page 225 and 226: 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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