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“Looking Back and Looking Ahead”
How Iowa State Shaped a Career in Geotechnical Engineering
Alan LuteneggerP.E. PhD. F. ASCEProfessor of CEE
University of Massachusetts
My Personal-Professional Journey
1975 BS. Construction Engineering
1977 M.S. Geotechnical Engineering
1979 PhD. Geotechnical Engineering
1980 PostDoc Iowa State
1982 NAS Bulgaria
1984-1989 Associate Prof. Clarkson College
1989 – Professor Univ. of Massachusetts
Coordinator – GT Program -10 Years
Department Head - 6 Years
1. Understand the Fundamentals of Soil Mechanics & Soil Behavior
You Don’t Know What Path Your Career Will Take So Learn Basics
Composition
Shear Strength
Consolidation
Modification/Stabilization
2. Understand How Composition May Influence Soil Behavior and
That Soils Are Inherently Complex
Time (min.)
0 500 1000 1500 2000 2500 3000
Sp
ecim
en H
eig
ht
(in
.)
0.750
0.760
0.770
0.780
0.790
0.800
0.810
0.820
0.830
0.840
0.850
Mt. Union, Ia. Paleosol
Initial Dry Unit Weight (Mg/m3)
1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0
Sw
ell
Pre
ssu
re (
kP
a)
0
200
400
600
800
Buckshot Clay
Heiden Clay
34/218 YSP
NLYSP
Vertical Stress (ksf)
0.1 1 10
Se
cim
en H
eig
ht
(in
.)
0.600
0.620
0.640
0.660
0.680
0.700
0.720
0.740
0.760
S.E. Iowa LoessW = 12.7%
Dry Density = 87.2 lbs/ft3
3. Don’t Be Afraid to Be an Expert Witness
Especially if You Think You Can Help Someone
“The Day the House Fell Again?”
4. Understand Surficial Geology
The Best Way to Understand Surficial Geology is to Go Look at it!
5. Be a Life-Long Student and Take Advantage of Opportunities to Learn
Something New
You Won’t Learn Everything at University and You Simply Can’t Learn Everything
Anyway
6. Understand and Appreciate the Classic GT Literature
A Lot of Really Good Fundamental Work Has Already Been Done – But Isn’t in
Textbooks
1960 – 3 GT Journals2017 – 27 GT Journals
Often Simple is Best
Free Swell Test
Linear Shrinkage Test
Fall Cone Test
SPT-Torque Test
Free Swell Test 1956
Lime Content (%)
0 2 4 6 8 10 12 14 16
Fre
e S
we
ll In
dex (
%)
0
200
400
600
800
1000
1200
1400
SWy-2
API-26
34 YSP
TS
Linear Shrinkage Test 1958
Fall Cone1915 & 1951
Age (Hours)
0.1 1 10 100 1000 10000
Undra
ined S
hear
Str
ength
(kP
a)
0
2
4
6
8
10
12
14
16
18
20
Texas Sodium
RS-101
RS-102
Theile RC-32
Gooselake
SHCa-1
SAz-1
Age (Hours)
0.1 1 10 100 1000 10000
Th
ixo
tro
pic
Str
en
gth
Ra
tio
1
2
3
4
5
6
7
8
Texas Sodium
RS-101
RS-102
Theile RC-32
Gooselake
SCHa-1
SAz-1
Water Content (%)
20 40 60 80 100 120 140 160 180 200
Und
rain
ed S
he
ar
Str
en
gth
(kP
a)
1
10
100
1000
10000
0% Lime
2% Lime
6% Lime
SPT-Torque Test - 1988
N60 (blows/0.3m)
0 10 20 30 40 50 60
f s (
kP
a)
0
50
100
150
200
250
300
fs = 4.1 N60
Std-1
Std-3 (donut)
Std-4 (Safety)
Std-2
What’s Going on Now and What’s In the Near The Future?
Finishing Academic Work at UMass - 2018
Completing Several Projects
Helicals & Jacked Piles in Clay
Adhesion of Drilled Piles in
Clay
Changes in Clay Behavior from Bored
Piles
(Meyerhof & Murdock 1949)
Grout Migration
Distance from Grout/Soil Interface (in.)
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Wate
r C
onte
nt (%
)
22
23
24
25
26
27
BBC 0 psi
BBC 5 psi
Distance from Grout/Soil Interface (in.)
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Po
cke
t P
en
etr
om
ete
r (t
sf)
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
BBC 0 psi
BBC 5 psi
Liquidity Index
-0.6 -0.4 -0.2 0.0 0.2 0.4
Cha
ng
e in
Wate
r C
on
ten
t at
So
il/G
rout
Inte
rfa
ce
(%
)
-4
-2
0
2
4
6
8
W/C = 0.6
Tomlinson (1957)
Parsons & Peck (1957)Chicago Clay S
t = 1.8
Water Content (%)
24 25 26 27 28
Undra
ined S
hear
Str
ength
(psf)
1000
Undisturbed
Remolded
104 Days
410 Days
Orrje & Broms (1967)Brunnsbo S
t = 30
Water Content (%)
70 72 74 76 78 80 82 84
Undra
ined S
hear
Str
ength
(ts
f)
0.001
0.01
0.1
1
Undisturbed
Remolded
9 Months
Flatte - 1972
Pipe Piles in Clay
HHF Extraction Piles Oct., 2016
Water Content (%)
15 20 25 30 35 40 45 50 55
De
pth
(ft
.)
0
1
2
3
4
5
6
7
8
9
10
BH1
2875C-1
2875C-2
BH-2
4.5 Open
6 Open
H-Piles in ClayHHF Extracted Piles 2016
Water Content (%)
20 25 30 35 40 45 50 55
Depth
(ft.)
0
1
2
3
4
5
6
7
8
W8 At Pile Surface
W8 At Failure Surface
BH1
BH-2
Soils and Geotechnology in Construction
June 2017
In Situ Testing Techniques in Geotechnical Engineering
December 2017
Design, Installation and Applications of Helical Piles and Anchors
June 2018
Lessons I was Taught(but didn’t know it at the time)
1. Understand the Fundamentals of Soil Mechanics
2. Understand How Soil Composition May Influence Soil Behavior and That Soils are Inherently Complex
3. Understand Surficial Geology
4. Don’t Be Afraid to be an Expert Witness
5. Be a Life-Long Student & Take Advantage of Opportunities to Learn Something New
6. Understand & Appreciate the Literature
Remember
It’s The Journey!
