SPT Relative Density -Army Corps

7/22/2019 SPT Relative Density -Army Corps

1/13

A4 fYhJ

.M 1 11 I

MISCELL NEOUS PAPER M 71 1

ST ND RD PENETR TION TEST NDREL TIVE DENSITY

byK.-J. Melzer

1 1

, t\>\ilf'tbtf< W'TCfi\i".YS f : { P [ R I ~ J ll

VI:CKSotUW

February 1971

Sponsored by U. S. Army Materiel Command

Conducted by U. S. Army Engineer Waterways Experiment Station, Vicksburg, Mississippi

This document has been approved for public release and sale; its distribution is unlimited


2/13

MISCELLANEOUS PAPER M 71 1

STANDARD PENETRATION TEST ANDRELATIVE DENSITYy

K.-J. Melzer

10 101101 O101

February 1971Sponso red by U. S. Army Materiel CommandDA Project No. IT062103A046 Task 03

Conducted by U. S. Army Engineer Waterways Experiment Station Vicksburg MississippiR M Y M RC VICKSBURG M ISS

This docum ent has been approved for pub lic release and sa le; its distribut ion is un limited


3/13

7v v 3 4 - ~

Y)-71-/

FOREWORD

This p ap e r was p rep a red by Dr. K.-J . M elze r as one of thelnited Sta tes ' s contr ibut ions to the Four th P a n Amer1c an Conference on

Soil Mec han1c s and Foundat ion Engineering in San Juan, Puer to Rico, 14-18 June 1971. The confe rence was organ ized as a Reg1onal Conference ofthe In ternat ional Society of Soil Mechanics and F1.undation Engineer ingand as a Specia l ty Confe rence of the A mer i can So< 1ety ot Ct vil Engineers .

The r e s e a r c h repor ted upon h e re i n was based on the au thor ' sdot tn ra l d1sser ta t ion and data col lected in studies < onducted a t the U. S.A r m y Engineer Waterways E x p er imen t Stat ion WES) under DA Pro jec t

T062103A046, Traf f i cab i l i ty and Mobil i ty Resea rch , Task 03, Mobi l Ity Fundamenta l s and Mode l Stud ies , under the sponsorsh ip and guidance of the Research , Development and Enginee r ing Direc to ra te , U. S.Arn1y Mater ie l Com m and .

COL E rn e s t D. Peixot to , CE, was Direc to r of the WES dur ingth is s tudy and prepara t ion of th is paper . Mr. F . R. Brown was Technica lDirec to r .

111

6954


4/13

STANDARD PENETRATION TEST AND RELATIVE DENSITYLa Prueba Norma l de Pene t rac ion y la Densidad Relativa

u s. K. J . Melzer , PhD, Research EngineerA rm y Engineer Waterways Exper iment Stat ionVicksburg, Mississippi U.S.A.SYNOPSIS

Since ground water grea t ly influences penet ra t ion res i s tance of soil ,an empir ica l re la t ion was establ ished between the number of blows ap-plied in the s tandard penetrat ion tes t to sand below ground water leveland the cor responding number applied to a ir dry sand at the same re l -ative densi ty. Also, since the number of blows was found to depend notonly on the re la t ive densi ty but also on the compactibil i ty and the grainsize of the penetra ted sand, an empir ica l relat ion was developed be-tween the number of blows and the re la t ive density, with compactibil i tyand mean gra in d iamete r taken into account . This relat ion was ver i -fied by results f rom labora tory tes ts conducted with a smal l sta t icpene t rome te r .

SINOPSISDebido a que e l agua subter ranea grandemente influve la res i s tenc ia ala penet rac ion de un suelo, se establecio una relacion empfr ica ent ree l numero de golpes en la prueba normal de penet racion (StandardPene t ra t ion Test ) de una a rena bajo e l nivel freat ico y e l cor respond-iente numero en una a rena seca (i .e. sobre el nivel freatico) con lam i s m a densidad re la t iva . Asimismo, porque se encontro que e l nu-mer o de golpes depende no solo de la densidad re la t iva sino tambie nde la comract ic idad y el tam,ano del grano d7 la arena penet rada, sedesar ro l lo una re lac ion emp ir ica entre e l numero de golpes y ladensidad re la t iva tomando en cuenta la compact icidad y e l d iamet romedio granula r . Es ta re lacion se veri f ico con los resul t ados obtenidosen ensayos de l abora tor io ejecutados con un penet romet ro esta t ico

equeno.INTRODUCTION

One of the main problems encountered in subsoi l e xploration is insi tu determinat ion of re la t ive densi ty and re la ted character is t ics ofcohes ionless soi ls . The deep penetrat ion tes t one of the ear l ies t ap-proaches to solution of this problem, yields resul ts that are used toempir ica l ly corre la te cer ta in soi l proper t ies with res i s tance meas -urements . In use today a re not only a varie ty of static and dynamicpene t romete r s but also numerous empir ica l and theoret ical re la t ionsbetween the results f rom speci f ic penet ra t ion techniques and the prop-er t ies of cohesionless soi l s , e .g. results f rom the standard penet ra t iont es t and re la t ive densi ty.The s tandard penetrat ion t es t (SPT) was developed pr imar i ly forsampling cohesive soi ls . Its secondary purpose was to measure

1


5/13

penetrat ion res is tance by counting the number of blows required todr1ve a sample r ft into the soil . The t e s t also is used today in cohesionless soi ls , but pr imar i ly as a method for measur ing penetrat ionres is tance ra ther than for obtaining undisturbed samples .The author 1s aware tha t the re is a cont roversy concerning the applic abili ty of the s tandard penetra t ion t e s t (Moretto, 1963; Irelandet al . , l q70). Nevertheless , a technique will be shown in this paper forevaluating the re la t ive densi ty of sand f rom the number of blows obtained f rom the s tandard penetrat ion tes t by taking into account thecompact ibi l i ty and the grain size of the sand under considerat ion andthe possible exis tence of ground water . Fur the rmore the techniquewill be shown to be applicable to the evaluat ion of re la t ive densi tyf rom penetrat ion res is tance m e a surements with sta t ic cone pene t rome ters . The concept, based on a few genera l considerat ions of whathappens dur ing a cone penetrat ion into sand, is pure ly empir ica l andi t is offered only as a beginning and an encouragement for fur therresearch .

TESTSResults of s tandard penetra t ion tes ts conducted under l abora toryconditions in four sands with different gradat ions (sands 1-4 in table I)

Table I Sand Proper t ies and Types of Tes tSand Source of Data Type of Moisture C om- Coeffi- M eanNo. Pene- Condit ion pact i - cient of Grain

t r om- bi l i ty Uniform- Diametere te r D i ty c d > c :l:c u m

mm1 U. S. Bureau of SPT Air-d ry 2.36 10.0 0.23Reclamation

1 953); Gibbsand Holtz (1957)2 U. S. Bureau of SPT Air-dry 1.31 5.0 1.40Reclamat ion sub-(1953); Gibbs mergedand Holtz (195 7)3 Menzenbach SPT Air-d ry 0.62 zr.o 0.42

(1959)4 Schultze and SPT Air -d ry 0.76 2.4 o. 55Melzer (1965) damp,sub-merged5 Melzer (1971) Cone Air-d ry 0.51 1.5 0.126 Melzer (1971) Cone Air-d ry 0.59 1.5 0.277 Melzer 1 971) Cone Air-d ry 0.63 2.5 0.50

,,,. . C ompac t ibi l i ty D = (emax - emin) / emin according to Terzaghi(1925).As defined by Burmis te r 1938) .2


6/13

w ere used d ~ v e l o p the ~ o n e p t ~ i s u s sed here in . Its applicabi l i ty tothe determ1nat lon of re lahve dens1ty f rom s ta t ic penetra t ion res i s tancewas evaluated f ro m cone penet rometer t e s t s conducted recent ly at theU S .. Ar.my. E.ngineer ~ t e r w y s Exper iment Station (WES}, Vicksburg,MlSSlSSlppl, 1n th ree d1fferent sands (sands 5-7 in table I), a lso underca reful ly control led l abora to ry condi t ions . The WES t e s t s w ere conducted with a mechanica l cone p en e t ro mete r ; the cone has a based i ame t e r of 2 _em and an apex angle of 30 degrees . This penet rometerwas not developed for deep penet ra t ions but for explorat ion of the topl ay e r (0 to l 5 em) of the soilunder cons iderat ion. The penet ra t ion speed in these t e s t s was0.03 m / s .A detai led descr ip t ion ofthe var ious so i l s and t e s t p ro ced u res is not within the scopeof th is paper ; there fo re onlycer ta in per t inen t proper t i es ofthe seven sands are l i s ted intable I, toge ther with thesources of data and the penet rome te rs used. Grain-s izedis t r ibu t ion cu rves a re p r e sented in fig. 1.

INFLUENCE O F GROUNDW A T E RIn a permeab le sand with agiven relat ive densi ty Dr the

SAN GR VEL

Gro 1n s1ze, mmFig . 1 Grain-Size Distr ibut ionCurves of Sands Invest igated

n u mb er of blows N of the s tandard penet ra t ion t e s t is smal le r belowground-water level than above the g round w ate r (Menzenbach , 1959;Rodin, 196 1; and Gawad, 1964). Some invest iga t ions s eem to indica tetha t the magni tude of th is difference depends on N and, there fo re onD r which is direct ly re la ted to N . But because most resul ts w erebased on f ield t e s t s in which re la t ive densi ty could se ldom be m e a s ured accura te ly the re is some doubt as to whether the relat ive densi tyabove the ground-water level was , in fact, the same as that below.To examine the effect of ground w at e r mo re closely the resul tsof the l abora to ry t e s t s on sand 4 ( table I}, which was tes ted not only ina i r - d r y and d am p s ta tes but a l so submerged, w ere evaluated as follows: The number of blows N counted in t e s t s conducted at a cer ta indepth and a t a cer ta in re la t ive densi ty with no ground w ate r presen twas compa red with the number of blows N f ro m t e s t s conductedbelow ground water a t the s ame depth and the same re la t ive densi ty. As ta t i s t ical analysis of the dq.ta yielded a l inear relat ion between N andN (fig. 2) for th is sand. In fact , this relat ion shows that for low Nva lue s the d ec reas e (in percen tage of N) f ro m N to N is l a rge rthan for high N values and the difference there fo re depends on re l ative densi ty . A s imi l a r evaluat ion of the resul ts of tes ts on sand 2,the only othe r sand without s i l t par t ic les for which resul ts f ro m t e s t sin a i r -d r y and submerged s ta tes were avai lable , shows the data pointsc lus te r ing fair ly well around the re la t ion between N and N forsand 4. F r o m these resul t s a caut ious conc lus ion might be drawn tha tfor medium and co a r s e sands the relat ion between N and N 1sm o r e o r l e s s independent of sand type.

3


7/13

4 0 ~ ~

0c:J30. ._-

01l>0

0z

-Of

E:Jz 10 N =5.27Correlat1on coeff1c1ent r :0 .909

Numberof data po1nts n=370and 4t:: and 20 ~ ~ ~ ~ ~ ~ ~10 20 30Number of blows N below ground water

Fig. 2 Influence of Ground Water onthe Number of Blows in the StandardPene t ra t ion Tes t

The number of blows issmal l e r below ground water thanabove because the effective unitweight of the sand in a sub merged s ta te is smal l e r than ina dry o r wet s tate and becausethe dynamic act ion of the penet ra t ing sampler causes a quicksand effect, a t l eas t in veryloose to medium-dense sands ,resul t ing in decreased penetrat ion res is tance . Therefore thenumber of blows measuredbelow the ground-water l eve l inmedium and coar se sands shouldbe corrected for these influences by means of the re la t ionin fig. 2 before an es t imate ofrelat ive density is made .

RELATIVE DENSITY EVALUATED FROM NUMBEROF BLOWSIn recent years compar i son of re la t ive density valuesevaluated f rom the number ofblows by various exis t ing re lat ions somet imes led to contras t ing resul ts Doscher, 1967; Tavenase t al. 1970), possibly because near ly al l such relat ions were developed

f rom resul ts of tes ts conducted in different types of sands . These dev iations a re not too surpr i s ing; however , the influence of the sand typeon the number of blows can be taken into account by re la t ively s implemeans .

When a cone or a s tandard penetrat ion t es t sample r pene t ra tes acohesionless soil , the grains a re displaced. The forces requi red fordisp lacement depend not only on the re la t ive density but also on compactibi l i ty in that the grains in a highly compact ible soi l can be dis placed with l ess difficulty than in a soil with a low compact ibi l i ty butthe same relat ive densi ty . Thus, penetrat ion res is tance is grea te r forthe l a t te r case . Ear l ie r invest igat ions with penetrometers support th isreasoning Kolbuszewski, 1957; Muhs, 1969). On the other hand, penet rat ion res is tance i s grea ter in a soi l with l a rge-d iamete r grains thanin a soil with smal l e r gra ins . For example , when a gravel and a sandw1th the same re la t ive densi ty and compact ibi l i ty a re penetrated, penet ra t ion res is tance is greater in the gravel . Thus, compact ibi l i ty andg ra in size the l a t te r character ized by the mean diameter influencethe re la t ion between re la t ive densi ty and the number of blows when thes tandard penetra t ion tes t is used.The genera l fo rm of one proposed relat ion Schultze and Melzer ,196 5) for the determinat ion of re la t ive density f rom the number ofblows, with overburden taken into considerat ion, is:

Dr = a 1 log N - a 2yD a 3 (1)where Dr = re la t ive densi ty in percent ; N = number of blows per 30em of penetrat ion; y = unit weight of the over lying soil; D = depth of

4


8/13

the point of the penet ra t ion t e s t belowthe soi l su r face ; yD = effect ive over -burden pres su re in kg/cm2; and a 1az and a3 are constants . F o reas ie r in terpreta t ion and compar i sonit is as su med that the tes ts w ere con-ducted at the soil sur face which l eadsto yD :: 0 and equat ion 1 becomes

2)f two sands are as su med to have

different compact ib i l i t ies and a3 = 0the re la t ion between re la t ive densityand number of blows can be plot ted asshown in fig. 3a.At the s ame relat ive densi ty , the

n u mb er of blows inc r eases with de -creas ing compact ib i l i ty . Angle 13whose tangent co r r e s ponds to constanta1 in equat ion 2, can then be seen toinc rease with increas ing compact ib i l -i ty . On the other hand, if two sandsare assumed to have the s ame com-pact ib i l i ty 13 = constant) and the samere la t ive densi ty , the number of blowsi nc rea se s with the m e a n grain diam -e te r (fig . 3b). Thus, the in tersect ionon the relat ive densi ty axis which isequivalent to constant a3 in equat ion2, dec rease s with increas ing meandiameter .

The above considerat ions w ereval idated by using the resul t s of t e s t swith sands 1, 2, 3, and 4. f equat ion2 in i ts genera l fo rm is valid for a l l

....a

-II

a

Sand( 0 =2)

Dr:orlog N + a 303 =0

t a n n ~ o

Number of blows log N0 RelatiOn between a and

-i+

Sand(dm=1)

Sandand gravel(dm: 8 )

a ,= ton n canst03 0

Number of blows log N.Q. Relot1on between a3 and dm

Fig . 3 Influence of Compact -ibi l i ty and Grain D iamete ron Number of Blows

sands (this point is not under discuss ion in this paper) , correspondingequat ions for sands 1, 2, and 3 can be establ ished . Constants a1 anda3 for the re la t ion between re la t ive densi ty and number of blowsmeas u red above ground water are given in table II.

Sand a lNo.1 46.12 38.33 30.64 31.7

Table II. Constants a1 and a3 (Equation 2)and a4 and a5 (Equation 3)

a3 Pen e t ro me t e r Sand a4 a5No.31.1 SPT 5 71.2 53.938 .2 SPT 6 7 5. 5 45.042.5 SPT 7 77.2 35.239 .2 SPT

Penet rometer

ConeConeCone

Plots of compact ib i l i ty D versus constant a1 (fig . 4a) andmean grain d iameter dm ve rsus constant a3 fig. 4b) show agreementwith the genera l considerat ions concerning the inf luence of D and

5


9/13

dm shown in fig. 3. As happens often, the re is one point (sand 1, fig.4b) that diminishes the validation. However , i f the fact is taken intoaccount that the data came f rom th ree sources and, therefore , maycontain some sca t ter , i t is surpr is ing that only one point is an out l ier .Thus, a t l eas t the genera l t rend of the observat ions concerning the in fluence of compactibi l i ty and grain s ize seems to be reasonable .

RELATIVE DENSITY EVALUATED FROM CONEPENETRATION RESISTANCETo conf i rm the above t rend and check whether the genera l concept is appl icable to the relat ion between relat ive densi ty and re s i s t ance to penet ra t ion of s tat ic cone penetrometers , the resu l ts of tes tswith sands S, 6, and 7 were analyzed as descr ibed above. A s ta t i s t ica lanalysis showed that the re la t ion between relat ive densi ty and average(0 - to l S -c m depth) cone penetrat ion res is tance qc for a specif ic sandcan be descr ibed bes t by a function of the genera l form:

D r = a4 log qc + as (3)Constants a4 and a forPlots of compactibil i?y D sands S, 6, and 7 are l i s ted in table II.versus constant a4 (fig. Sa) and mean

2.6

2.2

....~ 1 8-.0

TI

I-- - - .- - _. ....___

l r- lk 1--

I--x Sand 1

1o - 1 - t- - 0 Sand 23I0.6 ._ _ _._ ~ 4 ~

30 34 3 8 4 2 '6 soConstant a1

Q : Influence of 0 on o1E 1 s . . . . . - - . , . . - - - - ,EE0 , 2

....QlE oe00

30 34

Sando Sand

SandSand

38 42 46Constont a3

. ?.:_ Influence of dm on o3

123I

Fig. 4 Factors Affect ing Relat ion Between Relative Densi tyand Numbe r of Blows

6

0.7

-...u o.s0Q .E0u

0.5

I

/ 0 Sandt: Sando Sand70 80Constant a4..a.. Influence of D on a4

E o.s.E

567

91T

Jo.4 ~ - - - - - - -I-lE o . 3 t - - - + - - - - - ~ - - - + - - ~0-6c:0 0-21----+----+--___; : : - . . l

01c:0

I 0.1l :0 Sand 56 Sand 6e Sand 7

0 ~ 3 5 - - - - , ~ o - - - - ~ , s ~ - - - - s ~ o - - - - ~ s ~ s . . _ConstantA lnf l uence of dm on

Fig. S Factors Affect ing Relat ion Between Relative Densi tyand Pene t ra t ion Resis tance


10/13

gra in d iameter dm versus constant as (fig. 5b) show the same t rendobserved in the resul t s with sands 1-4, even though the overal l variat ion of D' and dm was not as broad in the cone penetra t ion tes ts asin the s tandard penet ra t ion t e s t s ; soi l select ion was l imi ted in the c onet e s t s by the capaci ty of the p r e s s u r e measu r in g device. Fur thermore ,the c one penet rometer , because of i ts grea te r sensi t ivi ty, respondedmuch mo re to a change in the mean grain d iameter than did the penet r o m e t e r in the s tandard penetra t ion tes t .

CONCLUSIONSIn the s tandard penet ra t ion test the number of blows measu red

for a given re la t ive densi ty is l a rger when the t e s t is conducted abovethe ground-water level than when i t i s conducted in submerged sand,at l eas t in m ed iu m and coa rse sands . Thus, before any es t imate ofre la t ive densi ty can be made, the number of blows counted below theg round-water l eve l must be cor rec ted for this inf luence. The cor rec t ion c an be made by means of the empir ica l ly es tabl ished re la t ion infig. 2. The number of blows depends not only on the relat ive densi ty,but also on the compact ib i l i ty and the mean gra in d iameter of the cons idered sand fig. 3). Based on a quali ta t ive explanation, an empir ica lre la t ion c an be used quanti ta t ively to take into account the effect ofcompact ib i l i ty and m e a n gra in diameter on the constants of a given r e l a t ion between re la t ive densi ty and number of blows (fig. 4). Compact ibi l i ty and m e a n gra in d iameter can be determined f rom dis turbedsamples t aken f ro m the boreho le in which the s tandard penetra t iont e s t is c onducted.The cone penet ra t ion res i s t ance in the s tat ic penetrometer tes tswas influenced by compact ib i l i ty and mean gra in diameter of the in vest igated sands in quali tat ively the same way as the number of blowswas influenced (fig. 5).

Fur the r r esea rch should be conducted to conf i rm and extend theb a s i c emp i r i ca l concept developed. A rea l s tandardizat ion of the

s t an d a r d penet ra t ion t e s t would be useful so that evaluat ions basedon the resul t s f ro m various r esea rch agenc ies would be mo re valid.REFERENCES

Burmis t e r , D. M. (1938), HThe Grading-Densi ty Rela t ion of GranularM a te r i a l s , Proceed ings of the American Society for Test ing Mater i als , Phi ladelphia , Pennsylvania , Vol 38, P a r t II, p 587.Doscher , H D. (1967), Rela t ionsh ips Between Sounding Resis tanceand Soil P r o p e r t i e s , Journa l of the Indian National Society of SoilMechanics and Foundat ion Engineer ing, New Delhi, Vol 6, No. 3,pp 313-33 7.Gawad, T. E. (1964), Study of the Natural and Mechanical P r o p e ~ t i e sof the Soil Forming the Sides of Suez Canal , ' ' Repor t No o 21, Engineerin g Depar tment , Res ea rch Center , Soil Mechanics and o u n ~ a t i o n Engineering Division, United Arab Republic Suez Canal Author i ty , SuezC anal Authori ty P re s s , Ismai l ia , Egypt.

6954


11/13

Gibbs, H. J . and Holtz, W. G. (1957), Resea rch on Determining theDensity of Sands by Spoon Penet ra t ion Tes t ing , Proceedings of theFourth International Conference on Soil Mechanics and Foundation Engineering, London, Butterworths Scientif ic Publications, London, Vol 1,p 35.Ireland, H. 0 . et al. (1970), The Dynamic Penet ra t ion Test: A Standard That Is Not Standardized, ' ' Geotechnique, Institution of Civil Engineers , London, Vol 20, No.2 , pp 185-192.Kolbuszewski, J . (1957), Discussion contribution, Proceedings of theFourth International Conference on Soil Mechanics and Foundation Engineering, London, Butterworths Scientif ic Publications, London, Vol 3,pp 126-128.Melzer , K.- J . (1971 ), Measur ing Soil Proper t i e s in Vehicle MobilityResearch; Relative Density and Cone Penet ra t ion Resis tance , Technical Report No. 3-652, Report 4 (in preparat ion) , U. S. Army EngineerWaterways Exper iment Station, CE, Vicksburg, Mississippi .Menzenbach, E. 1959), ' 'Die Anwendbarkeit von Sonden zur Prufungder Fest igkei tseigenschaf ten des Baugrundes , Forschungsber ichtedes Landes Nordrhein-Westfalen, No. 713, Westdeutscher Verlag,Koln.Moretto, 0 . (1963), Discussion contribution, Proceedings of the SecondPan Amer ican Conference on Soil Mechanics and Foundation Engineer ing, Sao Paulo, Vol 2, p 533.Muhs, H. (1969), Neue Erkenntnisse tiber die Tragfahigkeit vonf lachgegrundeten Fundamenten aus Grossversuchen und ihre Bedeutungfur die Berechnung, Die Bautechnik, Wilhelm Erns t Sohn, Berl in,Vol 46, p 181.Rodin, S. (1961), Exper iences with Penet rometers , with Part icu larReference to the Standard Penet ra t ion Tes t , Proceedings of the FifthInternational Conference on Soil Mechanics and Foundation Engineer ing, Par i s , Dunod, Par i s , Vol l , pp 517-521.Schultze, E. and Melzer , K.- J . (1965), The Determinat ion of the D ensi ty and the Modulus of Compress ib i l i ty of Non-Cohesive Soils bySoundings, Proceedings of the Sixth International Conference on SoilMechanics and Foundation Engineering, Montreal , Univers i ty of Toronto Pre s s , Vol 1, pp 354-358. ,Tavenas, F. e t al. (1970), Etude des sables submerges par echant i l -lonnage non r emanie , Canadian Geotechnical Journal , National Resea rch Council of Canada, Ottawa, Vol 7, pp 37-53.Terzaghi , K. (1925), Erdbaumechanik auf bodenphysikal ischer Grundlage, F. Deuticke, Leipzig.U.S . Bureau of Reclamat ion (1953), Second Progress Repor t of R esearch of the Penet ra t ion Resis tance Method of Subsurface Explorat ion, Report No. EM - 356, Design and Construct ion Division, Ear thMater ia ls Labor a tory, Denver , Color ado.

8


12/13

Unclas s i f edSe Clunty aaaificatlon

DOCUMENT CONTROL DATA. R DSecuri ty c lae 11/cal lon o l IIIIa, body o l abeltact and lndex /n J o ta t / 11 muet be when Ute 0 w11all report Ia claeellledj

1. ORIG IN A TI N G A C T IV I TY Co rporate aut/tot ) z.. R E P O R T SE C U R I TY CLASSIF I CA TIO NU . S. Army Engineer Waterw ays Expe r iment Station Unclassif iedVicksburg, Mi ss . 2b. GROUP

3. R E P O R T T I T L ESTANDARD PENE TRATION T EST AND RE LA TIVE DENSITY

4. DESC RI P T I V E N O T E S Type o l tepott and Inclus ive datee)Final Repor t

11 . AU THOR (S) F i r t IMUJI4, middle In it ia l, laet n ame)

Kl aus Ju rgen Melzere . R E P O R T O A TE 7a . TO T A L N O . O F P A G E S 7b N O . O F REFSF eb r uary 1971 10 15. CO N T R A C T O R GR A N T N O. N . O RI G I NA TO R S R E P O R T N U W8ER(S)b. P RO J E C T N O. 1T06 2l 03A046 Miscel l aneous Paper M - 71 lc. Task 03 8b . O T H ER R E P O R T NO(S) An, o t l tor mmobere .,._,_,be aeeftrtedt i t le report)d.

10. O IS TR I 8 U T ION STA T EM E N TThis document has been approved for publ ic re lease and sale; i ts d is t r ibutionis unlimited .

11 . s u P P LE M E N T A R Y N o T E S Paper to be presented a ta . SP ON SO RING M I L I T AR Y AC T I V I T YFour th Pan American Conference on Soil U. S. Army Materiel CommandMechanics and Foundat ion Engineering, Washington, D . C .San Juan, Puer to Rico, 14- 18 June 197 1

13 . A 8 S T R A C TSince ground water grea tl y influences penetrat ion res is tance of so i l , an empiricalrela t ion was establ ished between the number of b l ows applied in the s tandard p ene -t rat ion tes t to sand below ground -water leve l and the corresponding number appl iedto a ir - dry sand at the same relat ive density . Al so , since the number of b lows wasfound to depend not only on the re l ative density but also on the compact ib i li t y and thegrain size of the penetrated sand, an empir ica l relat ion was deve loped between thenumber of b l ows and the re l at ive density, with compact ibi l i ty and mean g r ain diam -e te r taken into account . This r e l a t ion was verif ied by resu l ts fro)'n l abo r atory tes tscqnducted with a sm all s ta t ic pene t rometer .

DD , .= 473l l laPLAC S DO OIIlW 147S I . IAN a4 WN I CN ISo e a o L T a o AlllWY u sa .

security Ciaaalflcatlon


13/13

Unclassif iedSecurity la meation

1 L INK A LINI< 8 L IN < CKEY wo. -os

. - o LE W OLE W . -oL IE W

Ground waterPenetra t ion res is tanceenetrometersSandsSoil proper t ies

Unclassif ied

Documents

SPT Relative Density -Army Corps