Seediscussions,stats,andauthorprofilesforthispublicationat:https://www.researchgate.net/publication/299452587

CorrelationbetweenPMTandSPTresultsforcalcareoussoil

Article·March2016

DOI:10.1016/j.hbrcj.2016.03.001

READS

26

1author:

MonaBadrEl-DinAnwar

TheGermanUniversityinCairo

3PUBLICATIONS0CITATIONS

SEEPROFILE

Availablefrom:MonaBadrEl-DinAnwar

Retrievedon:17June2016

HBRC Journal (2016) xxx, xxx–xxx

Housing and Building National Research Center

HBRC Journal

http://ees.elsevier.com/hbrcj

FULL LENGTH ARTICLE

Correlation between PMT and SPT results

for calcareous soil

* Address: Civil Engineering Department, The German University in

Cairo, Egypt.E-mail address: mona.anwar@guc.edu.eg.

Peer review under responsibility of Housing and Building National

Research Center.

Production and hosting by Elsevier

http://dx.doi.org/10.1016/j.hbrcj.2016.03.0011687-4048 � 2016 Housing and Building National Research Center. Production and hosting by Elsevier B.V.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Please cite this article in press as: M.B. Anwar, Correlation between PMT and SPT results for calcareous soil, HBRC Journal (2016), http://dx.doi.org/1hbrcj.2016.03.001

Mona B. Anwar *

Associate Professor, Civil Engineering Department, The German University in Cairo, EgyptAssociate Professor (on leave), Civil Engineering Department, Faculty of Engineering, Helwan University, Cairo, Egypt

Received 26 October 2015; revised 12 February 2016; accepted 1 March 2016

KEYWORDS

Pressuremeter;

SPT;

Calcareous;

Elastic modulus

Abstract The simplicity and low cost of the standard penetration test (SPT) have always been the

major advantages of this test over other field tests. Despite that other field tests (e.g. PMT, CPT,

DMT, . . .) are supposed to provide more reliable results, yet they are still costly and not feasible

in every project. Considering that SPT is available in all site investigation programs for all sizes

of project, it was tempting to provide correlations between SPT results and other field test results.

Through these correlations it will be feasible to estimate the soil parameters and deformation prop-

erties from the SPT number of blows. However, it is believed that correlations will differ, if the

tested soil is calcareous. Furthermore, adopting local correlations is more favorable as it caters

for the geological formation of the site. In this research it is aimed to obtain correlation between

the PMT results and the SPT results for calcareous soil. A site investigation comprising boreholes

with SPT and PMT was carried out near to the Red sea coast in Jeddah. The study was carried out

to develop a local correlation between the results of SPT and PMT considering the effects of soil

gradation and carbonate content. Comparison between the obtained correlation and other available

correlations is also considered.� 2016 Housing and Building National Research Center. Production and hosting by Elsevier B.V. This is

an open access article under the CCBY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Introduction

Pressuremeter test (PMT) was developed by Menard, in 1955to measure the in situ soil deformation properties, Briaud [1].

The pressuremeter consists mainly of a long cylindrical probethat is expanded radially into the surrounding ground. Bytracking the amount of volume of fluid and pressure used ininflating the probe, the data can be interpreted to give a com-

plete stress–strain–strength curve. The insertion of the pres-suremeter in ground depends on its type, either self-boringor pre-boring. PMT is considered theoretically sound in deter-

mining soil parameters and can test larger zone of soil massthan other in situ tests. Yet, PMT requires high level of skill

0.1016/j.

2 M.B. Anwar

and can easily be damaged, and above all it is relatively expen-sive, Mayne et al. [2]. Actually this test is not carried out inconventional geotechnical site investigation for typical pro-

jects, Charif and ShadiNajjar [3]. On the other hand, there isthe Standard Penetration Test (SPT), which is performedduring the advance of the boreholes and is already carried

out in all site investigation programs in nearly all boreholesdue to its simplicity and low cost. Due to the availability ofthe SPT in every site investigation program, it was tempting

to obtain correlations between SPT results (number of blows)and soil properties, namely shear strength parameters and soildeformation characteristic presented by the elastic modulus.Furthermore, correlations were also obtained to relate the

results of the SPT to the results of other field tests (e.g. CPT,PMT, DMT). Nevertheless, despite the many available corre-lations between the SPT and the CPT, there are still limited

number of correlations between the SPT and the PMT. ThePMT provides a direct measurement of the horizontal modulusof soil. This modulus (EPMT) often is presumed to be roughly

equivalent to the Young’s modulus (E), Phoon and Kulhawy[4]. Furthermore, both EH and EV are involved in the responseof the vertical loading. Several investigations found that it was

at most 5% difference between EH and EV, Briaud [1]. Never-theless, soil elastic modulus is the most difficult parameter toobtain as it depends on many factors such as stress level, strainlevel, soil density and stress history, Briaud [5] and Charif and

ShadiNajjar [3].Attempts have been made to correlate the EPMT with the

NSPT. Ohya et al. [6] proposed correlations for both clay soil

and cohesionless soil in Japan, Fig. 1. The correlations are wellknown, yet they are fairly weak, Phoon and Kulhawy [4].

Briaud et al. [7] presented a database of preboring pres-

suremeter test data and other field tests data (i.e. CPT andSPT). The sites were located in USA, 36 of them were sandformation sites and 44 were clay formation sites. Best fit

regressions were performed for the entire database. Eq. (1)presents the correlation proposed for the EPMT with NSPT insand. However, the scatter in the correlations was found verylarge. This drastic scatter made these correlations useless in

design, Briaud [1], Fig. 2a.

Eo ðkPaÞ ¼ 383Nblows

30 cm

� �; EoðtsfÞ ¼ 4N

blows

ft

� �ð1Þ

In 2008, Yagiz et al. [8] proposed correlations between NSPT

and EPMT results for sandy silty clayey soil based on 15 bore-holes in Turkey. The borehole depths were 5–8 m, and the tests

were carried out at depth 1.5–2 m only. Regression analysiswas undertaken and best fit regression between the parametersin a linear combination with 95% confidence level. The corre-lation is presented by Eq. (2). Fig. 2b presents the correlation,

based on only 15 results.

Em ¼ 388 Ncor þ 4554 ð2ÞIn 2010, Bozbey and Togrol [9], proposed a correlation

based on case study of 182 tests in Turkey as given in Eqs.

(3.a) and (3.b):

For Sandy soil : EPMT ðMPaÞ ¼ 1:33ðN60Þ0:77 ðr2 ¼ 0:82Þð3:aÞ

For Clayey soil : EPMT ðMPaÞ ¼ 1:61ðN60Þ0:71 ðr2 ¼ 0:72Þð3:bÞ

Please cite this article in press as: M.B. Anwar, Correlation between PMT and SPThbrcj.2016.03.001

Another correlation was given by Kenmogne et al. [10]based on site investigation data in Cameroon. The correlationwas linear and is given in Eq. (4).

Em ¼ b�N ð4Þwhere

b = 2–8 for gravely sand.

=2–20 for clayey sand.

Cheshomi and Ghodrati [11] presented correlations for siltysand and silty clay soil based on case study in Iran (38 tests for

silty clay soil and 16 tests for silty sand soil) given by Eqs. (5.a)and (5.b). These correlations are valid only for the range ofNSPT measured in site (i.e. 9–50 number of blows).

For silty sand : EPMT=Pa ¼ 9:8N60 � 94:3 ðr ¼ 0:79Þ ð5:aÞ

For silty clay : EPMT=Pa ¼ 10N60 � 26:7 ðr ¼ 0:85Þ ð5:bÞAs presented above, the available correlations between the

EPMT and the NSPT are either highly scattered (i.e. small corre-lation factor) or based on limited number of results. Yet theyare representing local correlations that are developed within

specific geologic setting. Reference to Phoon and Kulhawy[4] local correlations is preferable to generalized global correla-tions, but they need to be accurate, which leads to the need of

more studies and data to develop these correlations into moremature state. However, all cases using empirical correlationsshould be with caution as it is linking two items together that

are not directly related, Kulhawy [12]. Another factor needs tobe considered when adopting those correlations. This factor isthat these correlations are based on tests carried out in silic-

eous soil. Many references such as SPT, ElKateb and Ali[13], Kulhawy and Mayne [14], Ahmed et al. [15], Vafeianet al. [16], Schneider and Lehane [17] are discussing the differ-ence in behavior between calcareous or carbonate soil and

siliceous soil under field tests especially destructive tests. It isvery likely that destructive testing as SPT can possibly breakcementation of calcareous sand and may crush the actual sand

particles resulting in change in the physical properties of thesoil matrix, Charif and ShadiNajjar [3], which implies the needfor specific correlations for this type of soil. The aim of this

research was to provide correlation between the PMT andSPT results to be able to obtain the soil moduli taking intoconsideration the soil gradation and its calcareous nature.

Site characterization

The soil under study is located in Jeddah area, relatively near

to the Red Sea coast. The soil formation comprised ofinterbedded layers of silty/clayey sand with silty/clayey graveland sandy gravel, which is known as Wadi deposits. Cementa-tion was observed at some depths. Such layers continued from

ground surface down to 20 m depth. The in-situ compactnessof these layers was found generally to be medium dense to verydense. Layers of the cohesive soil were encountered at shallow

depths of 1.5 m in some boreholes and as deep as 18 m inothers. The thickness of the sandy lean clay layer ranged from1.5 to 3 m or more. The carried out site investigation com-

prised of many boreholes with depths ranging from 20 to50 m. PMT was carried out in 17 BHs and SPT was alsocarried out at depth interval of 1.5 m. Groundwater was

results for calcareous soil, HBRC Journal (2016), http://dx.doi.org/10.1016/j.

Fig. 1 Relationship between EPMT and NSPT value. Source: Ohya et al. [6].

Fig. 2a Example of correlations in sand from PMT data base.

Source: Briaud et al. [7].

Fig. 2b Relationship between measured and predicted Em.

Source: Yagiz et al. [8].

Correlation between PMT and SPT results 3

encountered at depths ranging from 4 m to 10 m. Laboratorytests (e.g. soil gradation, Atterberge limits, chemical analysis)

were carried out to determine the index properties of soil whichwere used in soil classifications. The soil had carbonate contentin the form of CaCo3 in average range of 5–20%, with some

samples showing higher carbonate content up to 40%. Referenceto modified Clark and Walker system, this soil is termed calcare-ous soil, Peuchen et al. [18]. Based on the gradation tests, soil

showed very wide range of fine contents and gravel contents.Accordingly, to be able to study the correlation between NSPT

and EPMT results, soil was divided into three groups based on

the D50 values which are reflected on the gravel contents as well.Table 1 and Fig. 3 present the three soil groups.

Standard penetration tests were carried out in the boreholesfollowing ASTM D1586 [19]. Tests were carried out at 1.5 m

Please cite this article in press as: M.B. Anwar, Correlation between PMT and SPThbrcj.2016.03.001

intervals. Fig. 4a presents the results of NSPT with depth forthe 17 BHs. The PMT was also carried out at the same depthinterval following the ASTM D4719 [20]. The pressuremeter

tests were executed using the Prebored, G type Menard pres-suremeter. The excavation for the PMT was carried out inthe cleaned bottom of the boreholes to drill hole to fit the

BX size probe. Fig. 4b presents the change of the obtainedEPMT with depth for the 17 BHs.

Results and discussion

The relation between the NSPT and the corresponding EPMT atsame levels was plotted for the three soil groups presented in

Table 1. Regression analysis was carried out to calculate theleast squares fit for the given points and the R-squared valueswere calculated to determine the accuracy of the relation. For

soil Group 1, the relation between NSPT and EPMT is presentedin Fig. 5. Values of the EPMT were normalized by the atmo-spheric pressure Pa (101 kPa). It is shown from figure thatthe scatter is relatively accepted relative to the correlations

results for calcareous soil, HBRC Journal (2016), http://dx.doi.org/10.1016/j.

Table 1 Soil groups.

D50 Fines content Gravel content Max. gravel size Remarks

Group 1 <0.25 25–50% <25% 610 mm Fines are silt or clay with low plasticity

Group 2 0.25–1 15–30% 20–40%

Group 3 >1 0–20% 35–70% Up to 100 mm

0

50

100

0.001 0.01 0.1 1 10 100

Group 1 Group 2Group3

Diameter (mm)

% p

ass

Fig. 3 Ranges of gradation for the 3 groups of soil used in the

current study.

y = 33.927x0.803

R² = 0.7104

10

100

1000

10000

10 100 1000

Soil Group 1

NSPT (blows/30)

E PM

T / P

a

Fig. 5 Relation between (EPMT/Pa) and (NSPT) for soil Group 1.

4 M.B. Anwar

proposed in the literature. The obtained correlation is pre-sented in Eq. (6).

Soil Group 1 : EPMT=Pa ¼ 33:92ðNSPTÞ0:803 ðR2 ¼ 0:71Þð6Þ

The same procedures were carried out for soil Group 2 and

the results are presented in Fig. 6 and the correlation is givenby Eq. (7). The regression analysis for soil Group 2 showedless accuracy for the obtained correlation as the calculatedR-squared was found to be only 0.385. This higher scatter

can be referred to the higher gravel content which increasesthe inconsistency of the SPT results. This inconsistency is

-15

-10

-5

0

5

10

150 100 200 300

NSPT

Lev

el(M

SL -

m)

(a)

Fig. 4 Field

Please cite this article in press as: M.B. Anwar, Correlation between PMT and SPThbrcj.2016.03.001

referred to either refusal under the SPT spoon due to gravel,or crushing of gravel under the impact which, in both cases,

will give misleading SPT results

Soil Group 2 : EPMT=Pa ¼ 38:428ðNSPTÞ0:7385 ðR2 ¼ 0:385Þð7Þ

The same trend was observed in soil Group 3 as presentedin Fig. 7 and by Eq. (8). The higher increase in gravel contentsadded to its large diameter (up to 100 mm) weakened therelation more and more which is reflected in the calculated

R-squared.

-15

-10

-5

0

5

10

150 100 200 300 400

EPMT - (MPa) (b)

test results.

results for calcareous soil, HBRC Journal (2016), http://dx.doi.org/10.1016/j.

0.7385y = 38.428xR² = 0.3851

10

100

1000

10000

10 100 1000

Soil Group 2

NSPT (blows/30)

E PM

T/ Pa

Fig. 6 Relation between (EPMT/Pa) and (NSPT) for soil Group 2.

y = 178.14x0.4398

R² = 0.1205

10

100

1000

10000

10 100 1000

Soil Group 3

NSPT (blows/30)

E PM

T/ Pa

Fig. 7 Relation between (EPMT/Pa) and (NSPT) for soil Group 3.

0

500

1000

1500

0 50 100

E PMT /P

a

N SPT (blows/30cm)

Predicted by the proposed correla�onYagiz et al 2008 Sandy silty clayey soilBozbey & Togrol 2010 Sandy soil

Fig. 8 Relation between (NSPT) and the predicted (EPMT/Pa).

Correlation between PMT and SPT results 5

Soil Group 3 : EPMT=Pa ¼ 178:14ðNSPTÞ0:4398 ðR2 ¼ 0:12Þð8Þ

Based on the above regression analysis, it can be concludedthat the applicability of correlation between the EPMT andNSPT is eliminated by the increase in gravel content and gravel

diameter.To compare the correlation of soil Group 1 with those pre-

sented in the literature, the predicted values of E, using Eq. (6)

for soil Group 1, were plotted versus the measured NSPT andpresented in Fig. 8. Correlations cited from Yagiz et al. [8]and Bozbey and Togrol [9] were also used to predict the Evalues for the measured NSPT and results are presented in

Fig. 8. Other correlations from the literature were limitedeither to small range of NSPT Cheshomi and Ghodrati [11] orhaving drastic scatter, Briaud [1] and Ohya et al. [6]. It is

noticed from the figure that the results from the proposedcorrelation is higher than those of the literature.

The difference can be attributed to the different soil and

geologic formation, calcareous nature and cementation insome depths. Accordingly, as stated above local correlations

Please cite this article in press as: M.B. Anwar, Correlation between PMT and SPThbrcj.2016.03.001

are preferred than global ones to cater for the site specificformation.

Conclusions

The proposed correlation, for soil Group 1, is considered aslocal correlation for this formation in Jeddah and also can

be considered applicable for soils having the same gradationand similar geologic formation. The proposed correlation forsoil Group 1 shows good accuracy relative to the published

correlations. The increase in gravel content changed the behav-ior and reduced the coefficient of correlation in soil Groups 2and 3. The proposed correlation for soil Group 1 provideshigher values for the elastic modulus for the same NSPT relative

to the correlations found in the literature and this is due to thedifference in soil (e.g. gravel content) and geological forma-tion, its calcareous nature and its tendency to break under

the SPT which reduces the equivalent NSPT.

Conflict of interests

The author wish to confirm that there is no known conflicts ofinterest associated with this publication and there isn’t anyfinancial support for this work that could have influenced its

outcome.

References

[1] J.L. Briaud, The Pressuremeter, first ed., A.A. Balkema,

Rotterdam, Netherland, 1992.

[2] P. Mayne, B.R. Christopher, J. DeJong, Manual of Subsurface

Investigations, FHWA NHI-01-031, 2001.

[3] K.H. Charif, A.M. ShadiNajjar, Comparative study of shear

modulus in calcareous sand and sabkha soils, ASCE,

GeoCongress 2012, Oakland, California, United States, March

25–29, 2012.

[4] K. Phoon, F. Kulhawy, Evaluation of geotechnical variability,

Can. Geotech. J. 36 (4) (1999) 625–639, http://dx.doi.org/

10.1139/t99-039.

results for calcareous soil, HBRC Journal (2016), http://dx.doi.org/10.1016/j.

6 M.B. Anwar

[5] J.L. Briaud, Introduction to Soil Moduli, Geotechnical News,

June 2001, BiTech Publishers Ltd, Richmond, B.C., Canada,

(geotechnicalnews@bitech.ca).

[6] S. Ohya, T. Imai, M. Matsubara, Relation between N value by

SPT and LLT pressuremeter results, in: Proceeding, 2nd

European Symposium on Penetration Testing, Amsterdam,

vol. I, 1982, pp. 125–130.

[7] J.L. Briaud, A. Noubani, A. Kilgore, L.M. Tucker, Correlation

between Pressuremeter data and other parameters, Research Report,

Civil Engineering, Texas A&M University, 1985 (Cited from J.L.

Briaud, The Pressuremeter, A.A. Balkema, Rotterdam, 1992).

[8] S. Yagiz, E. Akyol, G. Sen, Relationship between the standard

penetration test and the pressuremeter test on sandy silty clays: a

case study from Denizli, Bull. Eng. Geol. Environ. 67 (3) (2008)

405–410.

[9] I. Bozbey, E. Togrol, Correlation of standard penetration test

and pressuremeter data a case study from Estunbol, Turkey,

Bull. Eng. Geol. Environ. 69 (2010) 505–515.

[10] E. Kenmogne, J.R. Martin, S.A. Geofor, Correlation studies

between SPT and Pressuremeter tests, in: Proceedings of the

15th African Regional Conference on Soil Mechanics and

Geotechnical Engineering, 2011.

[11] A. Cheshomi, M. Ghodrati, Estimating Menard pressuremeter

modulus and limit pressure from SPT in silty sand and silty clay

soils. A case study in Mashhad, Iran, Int. J., Geomech. Geoeng.

10 (3) (2014) 194–202.

[12] F. Kulhawy, On the evaluation of static soil properties, in:

Honoring Fred H. Kulhawy (Ed.), Foundation Engineering in

Please cite this article in press as: M.B. Anwar, Correlation between PMT and SPThbrcj.2016.03.001

the Face of Uncertainty, Geotechnical Special Publication

ASCE, 2013, pp. 56–76.

[13] T.M. ElKateb, H.E. Ali, CPT-SPT correlations for calcareous

sand in Persian Gulf area, in: 2nd International Symposium on

Cone Penetration Testing. California, vol. 2, May 2010.

[14] F. Kulhawy, P. Mayne, Manual on estimating soil properties for

foundation design, in: Report no. EPRI-EL-6800, Electric

Power Research Institute, EPRI, 1990.

[15] S.M. Ahmed, S.W. Agaiby, A.H. Abdel-Rahman, A unified

CPT-SPT correlation for non-srushable and crushable

cohesionless soil, Ain Shams Eng. J. 5 (2014) 63–73.

[16] M. Vafeian, D.W. Airey, J.P. Carter, M.K. Islam, Analysis of

pressuremeter tests in calcareous soils, Engineering for

Calcareous Sediments. Proceedings of the Second International

Conference on Engineering for Calcareous Sediments, Bahrain,

February 1999.

[17] J.A. Schneider, B.M. Lehane, Evaluation of cone penetration

test data from a calcareous dune sand, in: 2nd International

Symposium on Cone Penetration Testing, California, May 2010.

[18] J. Peuchen, Ruijter, S. Geodemoed, Commercial characterization

of calcareous soils, in: Proceedings of the Second International

Conference on Engineering for Calcareous Sediments, Bahrain,

1999.

[19] ASTM D1586, Standard Test Method for Penetration Test and

Split-Barrel Sampling of Soils.

[20] ASTM D4719-07, Standard Test Methods for Prebored

Pressuremeter Testing in Soils.

results for calcareous soil, HBRC Journal (2016), http://dx.doi.org/10.1016/j.