N3319116R1004Attachment_1c_-_Performance_Technical_Statement_-_Missile_Warning_Facility_(Pages_778-874).pdf

Point of connection;

Use existing 'SW678' spare switch way

E-602

Point of power connection;

Use existing 'SW678' spare switch way

Approximate location of the site

Antenna Area

Point of Telecom connection;

E-101

Joint Tactical Ground Station (JTAGS) Relocation WO 1335929 Naval Air Station II Sigonella, Sicily, Italy

PART 6 - ATTACHMENTS - Page 6

REPORTS

DEPARTMENT OF THE NAVY

NAVAL FACILITIES ENGINEERING COMMAND

NAVAL FACILITIES EUROPE AFRICA SOUTH WEST ASIA

JOINT TACTICAL GROUND

STATION (JTAGS) RELOCATION

NAS II Sigonella, Italy

CONTRACT NO. N33191-10-D-0202 T.O.0067

GEOTECHNICAL REPORT

FINAL SUBMITTAL

AI&P ALBERTOIZZO&PARTNERS s.r.l.

architecture, engineering, planning & construction management

Via Mergellina n. 2, 80122, Napoli, Italia

November 2014

BLANK PAGE LEFT INTENTIONALLY

JOINT TACTICAL GROUND STATION (JTAGS) RELOCATION - NAS 2 SIGONELLA

JOINT TACTICAL GROUND STATION (JTAGS ) RELOCATION

NAS 2 SIGONELLA (ITALY)

1 GENERAL

2 REFERENCE CODES

2.1 U.S. codes

2.2 Italian codes

3 SUBSOIL INVESTIGATION

4 STRATIGRAPHY

4.1 Geology

4.2 Analysis of subsoil investigations

4.3 Hydrology

5 SOIL PHYSICAL AND MECHANICAL PROPERTIES

5.1 Soil type "A"

6 SEISMIC CLASSIFICATION

6.1 U.S. Code

6.2 Italian code

7 FROST PENETRATION

8 LIQUEFACTION POTETNTIAL

8.1 Expected magnitude

8.2 Grain size distribution

8.3 Standardized number of blows per foot (N1)60

8.4 Expected free field acceleration

8.5 Liquefaction verification

9 SOIL PROPERTIES SUMMARY

10 RECOMMENDATIONS FOR FOUNDATION TYPES

10.1 Ultimate load

10.2 Reaction modulus

11 CONCLUSIONS

12 BIBLIOGRAPHY

13 ANNEX 1 - SUBSOIL INVESTIGATION

1 GENERAL

The purpose of the present geotechnical report is to evaluate physical and mechanical properties of the soils in the U.S. Navy Base located in Sigonella, NAS2 (Italy), for the relocation of the "Joint Tactical

Ground Station (JTAGS)".

With reference to the seismic loads, according to the UFC 3-301-01

Sigonella NAS2 has the following parameters:

Short period spectral acceleration Ss = 1.39

One second period spectral acceleration S1 = 0.92

Peak ground acceleration (PGA) 0.55 g

According to Italian code (DM 14/01/2008), each site is classified with reference to its geographic coordinates, then the reference acceleration at the bedrock is assigned according to delay time considered in the design. Geographic coordinates of the site investigated are the following:

Lat. 37.41, Long. 14.92.

2 REFERENCE CODES

2.1 U.S. codes

UFC 3-301-01 – Structural Engineering with change 1 – May 2014

UFC 3-220-01 – Geotechnical engineering – Nov 2012

UFC 3-220-10n - Soil mechanics – Jun 2005

NCEER 97-0022 - Proceedings of the NCEER Workshop on

Evaluation of Liquefaction Resistance of Soils. - Dec 1997

2.2 Italian codes

Law No. 1086 dated 11/5/71 regarding reinforced concrete and pre-stressed reinforced concrete structures and steel structures.

Seismic Design for Buildings - Act No 64 dated 2/2/74

DM 14 -01-2008 New Technical Norms for building constructions

Circolare 02 febbraio 2009 n. 617/C.S.LL.PP.

“Redazione della mappa di pericolosità sismica”, Istituto Nazionale di Geofisica e Vulcanologia (INGV) - April 2004

3 SUBSOIL INVESTIGATION

A subsoil survey has been carried out by the firm “SIDERCEM” between September and October 2014, attached as annex and considered a part of the present report. The survey consisted in the drilling of 8 boreholes, one 30m deep and seven 10m deep, with SPT tests, with the retrieval of undisturbed samples for laboratory testing, and installation of four open pipe piezometers. Another firm under Government responsibility has inspected the borings during drilling and retrieved soil samples to perform environmental tests, not part of the present report.

The main in situ tasks of such survey are summarized in the following tables.

Table 1: Subsoil survey - continuous boreholes.

Boreholes

S1 S2 S3 S4 S5 S6 S7 S8

Length (m) 30.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0

SPT 8 2 2 2 2 3 3 3

Undisturbed samples 2 -- 1 -- -- 1 1 1

In the following table the laboratory tests performed on the retrieved samples are summarized, where it is also indicated the classification of each sample according to the stratigraphy described in the following chapter.

Table 2 - subsoil survey: laboratory tests.

Boring Sample Depth Soil Quality class Grain size1. Att. 2 TX(CU)3 Oed4 DS.5

S1 1 13.9 - 14.5 A Q5 X X X

S1 2 21.9 - 22.4 B Q5 X X X

S3 1 9.0 - 9.5 A Q5 X X X X

S6 1 2.0 - 2.3 A Q5 X X X

S7 1 5.3 - 5.8 A Q5 X X X

S8 1 4.1 - 4.6 A Q5 X X X X X

1 Grain size analysis (ASTM-D422, UNI CEN ISO/TS 17892-4/2005).

2 Atterberg limits (ASTM-D423, D424, D4318/UNI CEN ISO/TS 17892-12/2005).

3 Triaxial test Consolidated - Undrained (ASTM D2166/ UNI CEN ISO/TS 17892-9/2005).

4 Oedometer test (ASTM D2435/ UNI CEN ISO/TS 17892-5/2005).

5 Direct shear test (ASTM-D3080/ UNI CEN ISO/TS 17892-10/2005).

4 STRATIGRAPHY

4.1 Geology

The investigated area is included between Catania and Siracusa municipalities, and is reported in the sheet n. 269 "Paternò" of the Italian geological map scale 1:100000. Sigonella NAS 2 Base is located in the middle of Catania plain, an area of tectonic subsidence covered by recent fluvial deposits laid by Simeto River. Despite the proximity with Etna volcano, alluvial deposits instead of pyroclastic are mostly found in the area at issue within the depth of engineering interest.

4.2 Analysis of subsoil investigations

NAS2 area is almost flat, and in the past such uniformity has been reflected in the properties of superficial layers. The subsoil section is made mainly by a succession of clayey layers, with significant sandy and silty components.

Ground water has been found at 2.5 m below ground.

The plot of grain size analyses against depth indicates a general prevalence of silty and clayey lithology.

In next figure are plotted the number of blows per foot and the number of blows per foot standardized with respect to lithostatic pressure against depth. What is visible is a substantial uniformity in the count of values, with a light increase with depth. Values are aligned around the number of 12 blows. N1,60 gives a better comprehension of soil strength, since the standardized number of blows is strictly depending on the confining pressure, and consequently literature correlations work better with the modified N1,60 values.

0,0001 0,001 0,01 0,1 1 10 100

P d (mm)

S1-1

S1-2

S3-1

S6-1

S7-1

S8-1

LW BND

UP BND

0 20 40 60 80 100 z ( m

% in peso

A L S G

Figure 1: Grain size analyses plotted vs depth.

0 10 20 30 40 z (m

NSPT

0 10 20 30 40 z (m

N1,60

Figure 2: NSPT and N1,60 values plotted vs depth.

4.3 Hydrology

Four piezometers have been installed in the boring logs. Captation depth has been located between 1 and 10 m; due to the not negligible sandy fraction in the superficial layers, open pipe piezometers have been used.

Detected water table levels are shown in the following table.

-5

-4,5

-4

-3,5

-3

-2,5

-2

-1,5

-1

-0,5

18/ 09/ 2014 18/ 10/ 2014

Z b el ow g ro un d (m

Readings s2 s3 s7 s8

Serie9

Figure 3: ground water level.

Water table measurements have generally shown values around -2.5

m. In any case, open pipe piezometers will allow a monitoring of ground water level also during the future months. At present state, it has been assumed that maximum water level elevation is at -2.5 m below ground.

Figure 4: Borings location.

5 SOIL PHYSICAL AND MECHANICAL PROPERTIES

Since one single soil type has been identified, all samples can be assigned to "soil type A". In the following pages the physical and mechanical properties of such material will be investigated, based on the results of the field and laboratory tests performed in the 2014 survey.

5.1 Soil type "A"

Six samples have been analyzed, all undisturbed type. All values show very limited scattering; unit weight is around 19 kN/mc, representative porosity index "e0" may be set equal to 0.80, water content equal to 30% and consistency index 0.8. Since the values of the degree of saturation are always above 96%, it is assumed that the soil is fully saturated.

The plot in "Casagrande plasticity chart" indicates that the soil follows definitively in the "high plasticity" field; according to ASTM D2487 soil classification is generally CH, except for sample S7-1 classified as

"CL".

0 20 40 60 80 100

Ip

Wl (%)

Figure 5: Soil A - Casagrande plasticity chart.

2,5

7,5

12,5

17,5

22,5

27,5

10 12 14 16 18 20 22 z ( m kN/mc

0,8

0,80,8

0,8

2,5

7,5

12,5

17,5

22,5

27,5

0,00 0,40 0,80 1,20 1,60 2,00 z ( m e

2,5

7,5

12,5

17,5

22,5

27,5

0 20 40 60 80 100 z ( m w (%)

0,8

0,8

2,5

7,5

12,5

17,5

22,5

27,5

0,0 0,5 1,0 1,5 2,0 2,5 3,0 z ( m

Ic

Figure 6: Soil A - Physical properties.

Grain size analyses indicate that all samples, except for S7-1, have more than 90% in weight passing #200 sieve, with fine percentage included between 40 and 60%. According to grain sizes, soil is not liquefiable.

As indicated in previous paragraphs, representative number of blows per foot has been set equal to 12. In the table at next page the details of all tests are shown.

Due to grain sizes, SPT tests have been interpreted in terms of undrained shear strength; according to the most common correlations, its value is equal to cu=0.6 x NSPT, in this case 0.6 x 12 = 72.0 kN/m2

Boring Z1 Z2 Z D N1 N2 N3 N sigma'v n1,60

S5 1,6 2,05 1,8 0,45 3 5 7 12 3,285 37 S8 2 2,45 2,2 0,45 2 5 8 13 4,005 32 S3 2,3 2,75 2,5 0,45 3 5 7 12 4,545 26 S4 2,3 2,75 2,5 0,45 4 4 5 9 4,545 20 S6 2,3 2,75 2,5 0,45 3 5 7 12 4,545 26 S7 2,7 3,15 2,9 0,45 4 4 7 11 5,265 21 S1 3 3,45 3,2 0,45 4 5 7 12 5,805 21 S2 3 3,45 3,2 0,45 4 3 5 8 5,805 14 S6 4 4,45 4,2 0,45 4 4 4 8 7,605 11 S7 4 4,45 4,2 0,45 5 5 6 11 7,605 14 S5 4,4 4,85 4,6 0,45 7 10 11 21 8,325 25 S2 4,5 4,95 4,7 0,45 3 3 5 8 8,505 9 S8 4,7 5,15 4,9 0,45 4 5 6 11 8,865 12 S3 5,5 5,95 5,7 0,45 3 4 5 9 10,305 9 S6 5,8 6,25 6,0 0,45 6 7 11 18 10,845 17 S4 6 6,45 6,2 0,45 4 5 9 14 11,205 12 S1 6,2 6,65 6,4 0,45 2 4 5 9 11,565 8 S8 6,3 6,75 6,5 0,45 2 3 4 7 11,745 6 S7 8,3 8,75 8,5 0,45 11 11 12 23 15,345 15 S1 8,9 9,35 9,1 0,45 6 9 12 21 16,425 13 S1 16,4 16,85 16,6 0,45 3 4 5 9 29,925 3 S1 19,3 19,75 19,5 0,45 5 8 10 18 35,145 5 S1 22,4 22,85 22,6 0,45 4 7 8 15 40,725 4 S1 25,5 25,95 25,7 0,45 3 4 7 11 46,305 2 S1 28,5 28,95 28,7 0,45 5 6 9 15 51,705 3

Figure 7: Soil A - SPT tests.

Rupture parameters

Three consolidated undrained shear tests have been performed on samples retrieved at different depths; their results have been summarized in next figure, plotted in a Lambe chart.

Experimental points are well interpolated by a line that intercept "t" axe at 30 kPa, and grows with an angle of 12 degs. The diagram represents the relationship between undrained cohesion and cell pressure

(that means depth). For a given depth value, the undrained cohesion may be obtained by the following:

3726.0

12tan

1tan z sen sen sen senC c c cu cu cu u

0,00

50,00

100,00

150,00

200,00

250,00

0,00 100,00 200,00 300,00 400,00 500,00 600,00 700,00 t( kP a) s(kPa)

Soil A - undrained parameters

S1-2

S3-1

S8-1 c=30 beta=12

Figure 8: Soil A - Undrained parameters.

These results have been also plotted in a diagram having on the ordinate axis a depth equivalent to the consolidation pressure; in the same diagram the values of SPT tests are reported in terms of undrained parameters.

0,00 50,00 100,00 150,00 200,00 250,00 300,00 z( m

Cu(kPa)

TX - CIU test - SC soil - undrained parameters

S1-2

S3-1

S8-1

0.26gz+37

Cu by SPT

Figure 9: Soil A - Undrained cohesion vs depth.

The results are consistent between lab and in situ tests; to perform a conservative analysis, a value of 40 kPa will be adopted for undrained cohesion in the first 5.0 m, and 60 kPa below 5.0 m.

CIU tests have been also used to estimate drained parameters, by measuring water pressure at rupture. This allows also an evaluation of

Skempton coefficient "A" for water overpressure in undrained soil

31 Au . Average value determined in such tests is 0.40; since soil is saturated below 2.5 m, for design purposes it may be assumed that the other coefficient B is equal to 1.

0,00

0,20

0,40

0,60

0,80

1,00

1,20

1,40

1,60

1,80

2,00

0 100 200 300 400 500 600 700 800

A c(kPa)

TX - CIU test - Soil A - A parameter

S1-2

S3-1

A average

Figure 10: - "A" Skempton coefficient average value.

In a Lambe chart, experimental points in terms of drained pressures are well interpolated by a line that intercept the "t" axis at 20 kPa, and grows with an angle of 20. In terms of mechanical parameters, c'=20 and

'=21, being tan' arcsen .

0,00

50,00

100,00

150,00

200,00

250,00

0,00 100,00 200,00 300,00 400,00 500,00 600,00 700,00 t( kP a) s(kPa)

Soil A - drained parameters

S1-2

S3-1 c=20 beta=20

Figure 11: Soil A - drained parameters.

Drained parameters derived by CIU tests are fully consistent with direct shear drained test, as is shown in next figure.

A small scattering has been noted between peak resistance and residual values.

0 100 200 300 400 500 ta u (k Pa sigma' (kPa)

A soil c=20 fi=21

S6-1

S3-1

Figure 12: Soil A - Drained parameters by Direct shear tests.

Deformability parameters

A preliminary deformability estimate has been performed by correlations with the SPT tests results. In particular, Webb correlation has been adopted to obtain the oedometric modulus:

E = 3.16 x 12 + 15.8 = 53.7 kg/cm2 = 5266 kPa

Four oedometric tests have been performed on soil A, their results have been plotted in the following figure. Except for sample S7-1, experimental points are well interpolated by a normal consolidation line having Cc=0.25 with e0=0.9 at a reference pressure of 100 kPa, and by an unloading - reloading line having Cs=0.05.

Representative oedometric modulus may be obtained by the simple relation:

0 log

302.2 p p

Cc e Eoe

At 10 m depth, with a vertical pressure equal to 19x10-

10x8.5=105kPa, plus an increment of 100 kPa due to the extra load applied by the building:

kPaEoe 3439205 log

25.0

9.01 302.2

This value is consistent with in situ tests determinations.

0,01

0,11

0,21

0,31

0,41

0,51

0,61

0,71

0,81

0,91

0,1 1 10 100 1000 10000 e p' (kg/cmq) s3-1 s7-1 s7-1

Serie7

Serie8

Serie9

Serie10 s1-1

Figure 13: Soil A - Oedometric tests.

A representative value of 4000 kPa has been adopted.

Consolidation pressure values have been determined on the oedometric curves; Over consolidation ratio is always close to unity, taking also into account the subsoil nature and its deposition mechanism it is reasonable to assume that the soil is normally consolidated.

Oedometric tests allow also the determination of consolidation coefficient Cs and permeability coefficient k, which are required to study consolidation processes.

Experimental values are represented by the values 1.0E(-9) mm/s for the permeability and 3.0E(-2) mm2/s for the consolidation.

Details of the tests are available in the investigations report.

1,00E-08 3,00E-08 5,00E-08 7,00E-08 9,00E-08 z( m k(mm/s)

A soil - permeability at sample scale s1-1 s3-1 s8-1

0,00E+00 1,00E-02 2,00E-02 3,00E-02 4,00E-02 z( m

Cv(mmq/s)

A soil - consolidation coefficient at sample scale s1-1 s3-1 s8-1

Figure 14: Unit A - permeability (k) and consolidation (Cv) coefficients.

6 SEISMIC CLASSIFICATION

6.1 U.S. Code

The U.S. code classifies the foundation soils on the basis of the shear waves velocity (or similarly of the number of blows per foot) in the upper 30 m. Five different soil categories (A, B, C, D, E) for which the parameters of the response spectra are given, plus one (F) requiring specific analysis.

The classification has been made on the basis of the number of blows per foot.

bpf

N h N iSPT i

SPT 12

0.30

,30, 30, The values of NSPT,30 fall definitively in the middle of the “type E” field.

It should be said that the classification made on the basis of SPT tests is usually very conservative.

6.2 Italian code

Italian codes classify the foundation soils on the basis of the shear wave velocity (or similarly of the number of blows per foot) in the upper

30 m. In particular, five different soil categories (A, B, C, D, E) are identified for which the parameters of the response spectra are given, plus two (S1 and S2) requiring specific analysis.

Following the procedure that involves the undrained cohesion, the classification is between class "D" and "C". Conservatively, it has been assumed a class "D".

kPa c h c iu i u 60

,30, 30, Finally, since the area is unequivocally flat, the site is classified within the topographic category “T1”

7 FROST PENETRATION

According to UFC 3-310-01 frost penetration assumed for Sigonella is 127 mm. To prevent differential settlements due to the groundwater freezing, the base of all the foundations structures shall be located not less than 127 mm below the actual ground level.

8 LIQUEFACTION POTENTIAL

8.1 Expected magnitude

The expected magnitude for the seismic events in the Italian peninsula may be obtained by the document “Redazione della mappa di pericolosità sismica – rapporto finale” (INGV, 2004). In this document, in order to define the seismic threat, the whole national territory has been divided in seismogenetic areas, for which the maximum expected moment magnitude is given.

Sigonella falls in the seismic zone n. 935 “Iblei”, the maximum expected moment magnitude is 7.29.

8.2 Grain size distribution

A study has been performed on the grain size distribution to determine the “Uniformity coefficient“ Uc, defined on each curve as the

60% passing diameter versus the 10% passing diameter. Since the value is typically higher than 3.5, the upper and lower bounds of grain size distribution for soils suitable of liquefaction has been defined. Retrieved samples fall clearly outside the boundaries, thus it is assumed that the soil is not suitable of liquefaction for grain size distribution.

8.3 Standardized number of blows per foot (N1)60

Most of the simplified methods for the evaluation of the liquefaction potential assume as soil resistance parameter the number of blows per foot NSPT. The value must be standardized to an effective stress of 100 kPa (10 t/m2) and to an energetic performance of the 60% in the test execution. The following correction factor may be adopted:

SPT

v a

SPTN N

p

NCN

601 ' where pa is the atmosphere pressure, and ’v0 is the effective pressure at the stratum elevation.

According to the defined stratigraphy, the value of CN has been combined with the effective number of blows per foot, to obtain the standardized value within 20 m depth. The following figure shows the result of the analysis, plotted every 2 m.

0 2 4 6 z (m

CN

0 5 10 15 20 25 30 35 40 45 50 z (m

NSPT, (N1)60

(N1)60

NSPT

Figure 15: Standardized number of blows per foot vs depth.

8.4 Expected free field acceleration

U.S. Code

Expected free field ground acceleration has been defined on the basis of the design spectral response acceleration at short period SDS, divided by 2.5.

SDS = 2/3 x SMS, with SMS = Fa x Ss.

According to Fema 450 Fa in site class “E” is equal to 0.9, hence:

33.0 5.2

39.19.03 g ag

Italian code

Expected free field ground acceleration has been defined on the basis of the reference value on a type “A” subsoil (Bedrock). Italian code assigns to design site a value of 0.2257. The initial spectral acceleration is obtained by multiplying such value by an “S” factor, given by Ss x ST, with

ST is equal to 1, and Ss is given by:

63.12257.0273.250.140.280.150.140.290.0 0

F

Reference ground acceleration is:

3679.02257.063.1

8.5 Liquefaction verification

According to what is reported in the above paragraph, it can be said that:

The expected magnitude (7.29) is higher than 5;

The expected free field ground acceleration (0.33 g according to US code, 0.37 g according to Italian code) is higher than 0.10 g;

The depth of the ground water level (2.0 m below ground) is definitively lower than 15 m below ground;

The standardized number of blows per foot (15) is lower than

30;

The grain size distribution curves do not fall into the upper and lower bound defined by the code.

Despite the other parameters, according to grain size distribution the site is not suitable of liquefaction.

9 SOIL PROPERTIES SUMMARY

The above study allowed the identification of the following soil type:

Soil type A (CH according to UFC 3-220-10n)

Physical and mechanical properties are reported in the following table:

Table 1: Soil properties.

Soil type

(kN/m³)

Deformability

(kPa)

Rupture

Peak=Residual

(degs) C’ (kPa) Cu (kPa)

A CH 19.0 Eed = 4000 21 20

40 (0 to 5. m)

60 (below 5.

m)

The water table has been detected at 2.5 m below ground.

Frost protection depth is 127 mm below the current ground level according to UFC 3-301-01.

Soil is completely flat, hence there are no stability issues.

10 RECOMMENDATIONS FOR FOUNDATION TYPES

10.1 Ultimate load

Subsoil properties allow the use of shallow foundations for one/two story buildings. For higher buildings it is suggested a detailed study that takes into account the real building structure and dimensions, to compare the use of deep and shallow foundations. To avoid interference with ground water, the foundation level should be not lower than 2.0 m below ground.

Due to soil heterogeneity, ultimate load will be computed both in drained and undrained conditions, assuming the most conservative values.

In undrained conditions the ultimate load is independent of foundation dimensions, hence:

kPacNcDNqPult u 2064014.5 at ground level.

To perform the analysis in drained conditions, a tentative footing 2.0 x 2.0 has been envisaged below most heavily loaded columns.

Assuming a footing depth equal to 2.0 m, by Brich - Hansen formula:

2/4.640

0.2 0.100.192.6208.150.20.1907.7 mkN

B NcNcDNqPult cq

In case the foundation is cast at ground level, value in drained conditions is reduced down to 372 kN/m2.

Undrained conditions are the most conservative.

According to US standards, design load is obtained by ultimate load dividing by 3: Pdes = 206/3 = 69 kN/m2.

In case isolated footings are adopted, they will be connected one to each other by tie beams to minimize differential settlement. Beams must be stiff enough to minimize differential, a minimum thickness of 0.6 m is suggested, to be checked in the structural analysis depending on the building dimensions.

The superficial layer containing roots, topsoil and organic particles must be removed. A backfill with 30 cm deep coarse grained soil layer compacted at 98% of max ASTM D1586 is suggested.

10.2 Reaction modulus

Reaction modulus order of magnitude is still function of footing dimensions. For the isolated footing 2.0x2.0 m:

0.2 m kN

B

E k oed

11 CONCLUSIONS

As result of the present analysis, a design stratigraphy has been provided for the site at issue.

Subsoil is adequate to carry loads of shallow foundations in case of small structures (basements - one to two stories).

For seismic purposes, soil is a type "E" according to US code, type

"D" according to Italian code.

Water level is at -2.5 m below grade, frost penetration depth is 127 mm.

The soil is not suitable of liquefaction.

Suggested shallow foundation depth is 2.0 m below ground.

Napoli, 10/10/2014

12 BIBLIOGRAPHY

SHIOI Y., FUKUI J. - Application of N-value to design of foundations in Japan (Proceedings of the second European symposium on penetration testing, Amsterdam), 1982

DENVER, H - Modulus of elasticity for sand determined by SPT and CPT (Proceedings of the second European symposium on penetration testing, Amsterdam), 1982

VIGGIANI, Carlo - Fondazioni (2003)

BOWLES, Joseph - Foundation analysis and design (1996)

13 ANNEX 1 - SUBSOIL INVESTIGATION