1

Challenges and Opportunities

in Geotechnology(a personal view, from the USA, in 2005)

W(H)YDOC - ENPC 2005

J. Carlos SantamarinaGeorgia Institute of Technology

Particulate Materials (soils view)

XVIII-XIX General - Coarse Coulomb, Darcy, Hertz, Reynold

1910: Fine soils (through 1950’s) Gouy & Chapman, Goldschmidt, Lambe & Mitchell

1920: Saturation (dynamic 1960's) Terzaghi, Biot

1950: p’-q-e (through 1960’s) Taylor, Roscoe, Schofield

1960: Unsaturated/mixed fluid Aitchison, Bishop, Morgenstern & Fredlund

Small-strain (through 1990's)

1980: Energy coupling Mitchell

1990: Soils at high σ' - crushing Bolton, Tanaka

Lightly cemented soils Tatsuoka, Fahey

2

Particle Forces – Spherical Particles

Skeletal

Weight

Buoyant

Hydrodynamic

Capillary

Electrical

attraction

repulsion

Cementation

2d'N σ=3

ws d)6/G(W γπ=3

ww d)6/(VolU γπ=γ⋅=

dv3Fdrag µπ=

dTF scap π=

dt24

AAtt 2

h=

dec0024.0pRe o8 ct10

o−=

dtT tenσπ=

boundary-determined

particle-level

contact-level

µN

mN

nN

µm mm

Att

Fcap

WN 100 kPa

diameter d

forc

e

123Skeletal

Weight

Buoyant

Hydrodynamic

Capillary

Electrical

attraction

repulsion

Cementation

Force Balance: Deformation, Strength …

3

Watson (1950's): DNA

nih.gov

Fascinating …. but, is it important?

Geotechnology: Fascinating !

Are we on the asymptote?

What are the important questions in our field ?

Meaningful research ?

4

A Few Challenges

Population Growth

< 1.0 %1.0-1.5 %1.5-2.1 %2.1-3.0 %

> 3.0 %No information

www.un.org

5

1950 1975 2001 2015 1 New York 12.3 1 Tokyo 19.8 1 Tokyo 26.5 1 Tokyo 27.2 2 New York 15.9 2 São Paulo 18.3 2 Dhaka 22.8 3 Shanghai 11.4 3 Mexico City 18.3 3 Mumbai 22.6 4 Mexico City 10.7 4 New York 16.8 4 São Paulo 21.2 5 São Paulo 10.3 5 Mumbai 16.5 5 Delhi 20.9 6 LA 13.3 6 Mexico City 20.4 7 Calcutta 13.3 7 New York 17.9 8 Dhaka 13.2 8 Jakarta 17.3 9 Delhi 13.0 9 Calcutta 16.7 10 Shanghai 12.8 10 Karachi 16.2 11 Bs As 12.1 11 Lagos 16.0 12 Jakarta 11.4 12 LA 14.5 13 Osaka 11.0 13 Shanghai 13.6 14 Beijing 10.8 14 Bs As 13.2 15 Rio de J. 10.8 15 Manila 12.6 16 Karachi 10.4 16 Beijing 11.7 17 Manila 10.1 17 Rio de J. 11.5 18 Cairo 11.5 19 Istanbul 11.4 20 Osaka 11.0 21 Tianjin 10.3

www.un.org

Urban Population Growth

Tokyo: 26 M

6

México: 18 M

San Pablo: 18 M

7

John Bazemore, AP.

http://www.nigeriaportal.com/images/lachaos.gif

Transportation

http://www.tripledub.com/MT/archives/P3120046.jpg

Drinking water

a personal experience …

8

Health

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80 90 100

Healthy Life Expectancy [yr]

Nu

mb

er o

f Co

un

trie

s

Data: http://www3.who.int

Health

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80 90 100

Healthy Life Expectancy [yr]

Nu

mb

er o

f Co

un

trie

s

JapanSwitzerlandSwedenAustraliaFranceIcelandItalyAustriaSpainNorwayGreeceNew ZealandGermanyFinlandDenmarkNetherlands

SudanSenegalEritreaCongoHaitiGuineaNigeriaSouth AfricaKenyaNamibiaCameroonEthiopiaChadUgandaLiberiaMozambiqueMaliSomaliaCongoRwandaBurundiAfghanistanNigerBotswanaZimbabweZambiaMalawiAngolaSierra Leone

Data: http://www3.who.int

ChileCosta RicaUruguayPanamaMexicoArgentinaDominicaVenezuela

Korea

9

(Annual Energy Review 2003 -www.eia.doe.gov

0

100

200

300

400

500

600

700

1960 1980 2000 2020 2040

Year

En

erg

y [1

015 B

Tu]

production

consumption

Energy Consumption

Production and Consumption by Region

(Annual Energy Review 2003)

0

50

100

150

Production Consumption

North, Centraland SouthAmerica

WesternEurope

E. Europe& FormerU.S.S.R

MiddleEast

Africa Asia and Oceania

En

erg

y [1

015

Btu

]

10

Energy Consumption in USA - Sources

http://www.eia.doe.gov

Petroleum 37%

Natural Gas 24%

Coal 24%

Uranium 8%

Propane 2%Hydropower 3%

Biomass 3%

Geothermal, Wind & Solar 0.5%

Carbon Emission

EE/FSU is Eastern Europe/Former Soviet Union

(Int. Energy Agency)

0 1 2 3 4 5 6 7

1997

2020

China

EE/FSU

Western Europe

South Korea

Canada

United States

Metric Tons of Carbon per Person

11

Global Warming

geographical distribution of annual-mean temperature rise on land surface. The result is difference between the mean temperature during 1971-2000 and the mean temperature during 2071-2100 http://www.jamstec.go.jp

Hydrates

12

Opportunities

Bio-mediated Geochemistrycementation

clogging

gas generation

13

TEM - http://www.danforthcenter.org/

Bio-technology

Bacillus subtilis

~1 µm

0.001

0.01

0.1

1

10

100

1000

10000

0.001 0.01 0.1 1 10 100 1000Particle size [µ m]

Dep

th [

m]

Possible pore size reduction by grain

crushing

Pores > 1 µm Throats > 1 µm

Pores > 1 µm Throats < 1 µm

Pores < 1 µm Throats < 1 µm

Montmorillonite

Illite

KaoliniteSilt Sand

with Rebata-Landa

14

0.001

0.01

0.1

1

10

100

1000

10000

0.001 0.01 0.1 1 10 100 1000Particle size [µ m]

Dep

th [

m]

Mobilization

Limit of soil skeleton consolidation

Limit of particle buckling

Limit of mechanical loading

Diffusive nutrient transport

(3a)

(3b)

(4)

(5)

(1)

(6)

(2)

Trapped Motile

Montmorillonite

Illite

KaoliniteSilt Sand

with Rebata-Landa

0.001

0.01

0.1

1

10

100

1000

10000

0.001 0.01 0.1 1 10 100 1000Particle size [µm]

Dep

th [m

]

ACTIVE AND MOTILE

Possible pore size reduction by grain

crushing

Trapped but may open channels

TRAPPED

Trapped and indented

(spore-forming species might be dormant)

DEAD

with Rebata-Landa

15

Nano-Technologyinherently geo

Nano-technology

1959: Feynman "There’s plenty of room at the bottom"

1981: Binning y Rohrer … STM … Nobel prize

1990: Eigler … nano-manipulation

2000: Clinton ... National Initiative on nano-technology

16

Montmorillonite: Nano-Particle

MDL / www.soils.wisc.edu/virtual_museum/index.html

Si tetra

Si tetra

Al octa

O=

O=

9.6 Å

Dry

In Water

C

H

OH

Na

C

H

CO

H2O

Polymer-based Control NaPAA:

with Palomino

17

Polymers sticking out

http://www.macleans.school.nz/students/science/Funscience/marcie_2.jpg

touching a van der Graaf generator…

Tip radius: 20 nm Stiffness :0.58 N/m

Laser beam

Photodector

Atomic Force Microscopy

with Wang

18

1

0 50 100 150 20030

10

10

30

50

nm

nN

Immersed in water

nN

nm

1

0 50 100 150 20030

10

10

30

50

nm

nN

Dry, ambient RH

nN

nm

with Wang

Information Technologyconcurrent developments

19

Submicron electronic devicesMore than 30 nano-technology research centers in the US.

2000's

Rapid growth in digital memory and storage capabilities. IBM Deep Blue defeats G. Kasparov (1997)World wide web.

1990's

Personal computers & CD players, commercial cellular phonesTexas Instrument: single-chip digital signal processorGrowth of micromachining

1980's

Microprocessors: computers = chipConsumer electronics begin transition to digitalA.M. Cormack and G. Hounsfield receive the noble prize for computerized tomography

1970's

Computers emerge. Growth of digital signal processing - FFT by Tukey and Cooley

1960's

Sony pocket-size transistor radio. Shannon message can be encoded and transmitted in "bits" Integrated circuits at Texas Instruments (1958).

1950's

The first digital computer by H.H. Aiken (1944). Transistor at Bell Labs (1947 – Nobel Prize: J. Bardeen, W. Brattain, and W. Shockley). Digital signal processing starts.

1940's

Car radios and portable radios become common.1930's

The field of consumer electronics starts with the sale of radios and electronic phonographs. 1920's

I. Fredholm introduces the concept of the generalized inverse for an integral operator (1903). 1910's

Mechanical calculators Schickard (1592-1635), Pascal (1623-1662), Leibniz (1646-1716). H. Hollerith (1860-1929) electronic counting for the 1890 US census; later founds IBM.

Before 1900

1.E+03

1.E+05

1.E+07

1.E+09

1970 1980 1990 2000 2010

Year

Tra

nsi

sto

rs p

er C

hip

40048080

8086

8028680386

80486

Pentium & 80786

Pentium IIIPentium IV

Microelectronics – Moore's Law

data from J. Birnbaum and A. Akinwande

doubles

24 months

20

0.00001

0.001

0.1

10

1000

100000

1950 1960 1970 1980 1990 2000 2010Year

Kilo

byt

es p

er d

olla

r

Storage

(data from Kurzweil 2001)

doubles

14 months

0.000001

0.0001

0.01

1

100

10000

1000000

100000000

1900 1920 1940 1960 1980 2000

Year

(Cal

cula

tions

/sec

ond)

/ $1

000

Calculations per second

(data from Kurzweil 2001)

doubles19 months

21

Communications

(data from Kurzweil 2001)

0.0001

0.01

1

100

10000

1000000

100000000

1940 1950 1960 1970 1980 1990 2000 2010

Year

MB

ytes

per

sec

ond

0.0000001

0.00001

0.001

0.1

10

MB

ytes

per

sec

on

d p

er $

doubles10 months

doubles

7 months

wireless

Sensors - MEMS

22

Cantilever displacement sensor

Yaralioglu et al 1998

Micro-electrical mechanical systems MEMS

Motor (U. Colorado Boulder)

Micro-electrical mechanical systems MEMS

23

Micro-mirror array (Bell Labs)

Micro-electrical mechanical systems MEMS

http://www.fiso.com

Fiber optic based pressure transducer

24

Signal Processingsensor data in digital form

-1

0

1

2

0 10 20 30 40 50 60 70 80 90 100

Days

Wat

er L

evel

[m

]

Den

nis

(7/4

)

Em

ily (7

/9)

Kat

rina

(9/2

9)

Rita

(11/

23)

Signals → Information

25

1 signal

2 signals

4 signals

8 signals

16 signals

32 signals

64 signals

128 signals

256 signals

512 signals

1024 signals

2048 signals

Even in the presence of noise ..!

Rebata-Landa

Data Fusion

http://www.pc.rhul.ac.uk/zanker/teach/PS1061/L6/braille.JPG

http://sunsite.tus.ac.jp/multimed/pics/animals/bat.jpg

26

•boundary deformations → volumetric strain field ( )' ' 'c f oC logε = σ σ

•travel time S-waves → shear wave velocity field ( )' '

sV2kPa

β

⊥ σ + σ = α

P

•electrical resist. → electrical conductivity field ( )soil fluid fluidelec elec c elecn f C , ',σ = σ = σ σ

travel time EM waves → EM wave velocity field ( ) ( )EM cc

V f w f C , ''

= = = σκ

fuse multisensor data → infer the field of mean effective stress in soil mass.

Data-fusion in geotechnology

Databasesfrom medicine ….

to geotechnology

27

(Bronowski 1973)

Systematic Organization of Information

Mendeleev (1860's)

coefficient of uniformity, Cu

1 2 3 4 5 6 10

1.4

1.2

1.0

0.8

0.6

min

imum

em

inm

axim

um e

max

0.8

0.6

0.4

0.2

Packing density

28

Fraser 1935. Youd 1973. Shimobe and Moroto 1995. Miura et al. 1998. Maeda, 2001. Cubrinovski and Ishihara 2002

coefficient of uniformity, Cu

1 2 3 4 5 6 10

1.4

1.2

1.0

0.8

0.6

min

imum

em

inm

axim

um e

max

0.8

0.6

0.4

0.2

0.1 0.3 0.5 0.7 0.9

0.9

0.7

0.5

0.3

max

i

rNr

roundness ∑=sp

heri

city

0.1 0.3 0.5 0.7 0.9

0.9

0.7

0.5

0.3

max

i

rNr

roundness ∑=sp

heri

city

Packing density

Critical State Friction Angle

?

10

20

30

40

50

0 0.2 0.4 0.6 0.8 1

Roundness R

CS

fric

tion

angl

e

cv

rotational frustration (e?)

vs. chain collapse (e?)

cv 42 17 Rφ = − ⋅

29

http://www.brgm.fr/

Information: GIS for Paris

Geophysicssensing at boundaries - inversion

30

(Mat. Eval. 1999)

Medical Diagnosis

GPR

(Oristoglio and Birken, 2002)

31

Inversion Mathematics - Tomography

Unknown internal conditions

?

32

33

1

4

2

3

Discretize into pixels

34

S1 R1

1

4

2

∗h1,1 h1,2

3

2

2,1

1

1,111 V

hVh

t +=→

S1

S2

R3

∗

R4

R1

R2

1

4

2

∗h1,1 h1,2

3

2

2,1

1

1,111 V

hVh

t +=→

h2,3 h2,4

4

4,2

3

3,222 V

hVh

t +=→

35

S1

S2

S3 S4

R3

∗∗

∗

R4

R1

R2

1

4

2

∗

3

⋅

=

4

3

2

1

4,42,4

3,31,3

4,23,2

2,11,1

4

3

2

1

V/1

V/1V/1V/1

h0h00h0h

hh00

00hh

t

ttt

⋅

=

N

k

1

N,Mk,M1,M

N,ik,i1,i

N,1k,11,1

M

i

1

V/1...

V/1...V/1

h...h...h...............h...h...h

...............h...h...h

t...

t...tN

1

36

0 100 200 300 400 500 600 70016

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

Time [microsec]

Mea

usre

d Si

gnal

Soil = innate sensing system

Tomography: Stress imaging

Before Loading

With Loading

Difference

(Simulations with ART)

37

spatial variability of permeability(3)pore pressure in observation wells

evolution of stiffness and attenuation(2)earthquake induced ground vibration

stress-strain soil parameters along the piledeformation data along a pile

coef. consolidation, secondary compressiontime-varying building settlement

tomographic image, or Vs(z) from SASW (1)geophysical data

location and timing of leak pollutant concentration in the subsurface

coefficient of consolidation, hydraulic conduct.time-varying pore pressure in an oedometer

constitutive parametersforce and deformation data - triaxial test

Inverted ValuesMeasured Values

Inverse Problems: Ubiquitous in Geotech

Remote Sensingsensors + signal processing

38

39

Teotihuacan

40

Tectonic displacement field after the 1994 Northridge earthquake Ref.:Pelzer, 2003

Synthetic Aperture Radar

Ground surface subsidence induced by changes in groundwater in Phoenix, ArRef.:Tatlowand Buckley 2003

41

Closing Thoughts

Soils have taken a remarkable journey in the last 100 yr

Soil characterization is changing…

42

Soil characterization is changing…

potentially short timerequired long timeComprehensive characterization

one may be sufficientmanyNumber of tests

as much as neededvery limitedInferred information per test

comprehensive inverse problemsimplest inversion Interpretation - Inversion

many, spatial and/or temporalvery fewMeasurements

extensive, multisensorminimal instrumentationInstrumentation

heterogeneous fieldhomogeneous fieldField conditions sought

complex boundary conditionssimplest possibleBoundaries

a few, information-rich testsmany simple tests Philosophy

New ParadigmOld Paradigm

Soil characterization is changing…

43

HB Calendar

Design&construction are changing:

known adequate safetyprobably over designedSafety

important potential savingshigher than neededTotal construction cost

comprehensive inversionjust measured dataInferred information

continuous - extensively usedminimal - limited useInterpretation

continuous monitoring sporadic measurementsDuring construction

spatially distributed, multi-modeminimalSensor system

adequate/optimal designsafe designPhilosophy

New ParadigmOld Paradigm

The Observational Method in the information age

Design&construction are changing:

44

Martell, 1999

Yet… still a ways to go…

It will not be about resources…

(Goodman)

Terzaghi (1920s)

45

We are not lacking challenges or opportunities

There are countless fascinating questions - chose important ones

Dedication, commitment, passion avoid alienations: e-mail, phone …

The best way to predict the future is to create it (Alan Kay)

Engineers: actors of change and creation

Promote creative attitude and a creative collective community

About choices…

Sleeping Beach – Antoni Pitxot – Museu Dali

Soils remain fascinating …

46

Thank You