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Geotechnical Properties of Glacigenic Soils
and Slope Stability
David A. FranziCenter for Earth and Environmental Science
SUNY Plattsburgh
• Introduction• Provide background information and
references
• Formulate hypotheses and experimental design
• Articulate workload and final product expectations
• Content and Skills Exercises (data collection & analysis)
• Individual or small group assignments
• Compilation of cohort database
• Interim reports are due upon completion of each exercise
• Capstone Exercise (synthesis)
• Students are encouraged to discuss interpretations but writing is an individual effort
• Emphasize connections between effective writing
General Laboratory Format
Skills and content exercises are organized around a central research question.
Skills & Content Exercises• Morphometry (topographic mapping & cross
sections)
• Sediment Composition (mineral, chemical, and etc.)
• Gravimetric Analyses
• Particle Size Analyses
• Atterberg Limits
• Soil Classification
• Hammer-Seismic Profiling
• Shear Tests
Capstone Exercises• Soils as Engineering Materials
• Glacial Sedimentology and Stratigraphy
• Sediment Provenance
• Slope Stability Analysis
Laboratory Exercises for
Geotechnical Properties of Soils and Mass Wasting
1) Topographic and Geologic Survey (Weeks 1-2)*• Measure stratigraphic section
• Collect and prepare samples for gravimetric and particle-size analyses
• Produce a topographic map and geological cross-section
2) Gravimetric Analysis (Week 2)• Lab analysis runs concurrently with topographic and geological survey exercise,
data are reported with the particle-size analysis
• Determine volumetric water content, porosity and density of soil samples
3) Particle-size Analyses (Weeks 3 and 4)• Sieve and hydrometer (or Coulter Counter) methods• Compile hourly and daily databases
4) Atterberg Limits (Week 5)• Determine liquid and plastic limits on clay soils
5) Soil Classification (Week 6)• Classify soil types using the Unified Soil Classification
6) Slope Stability Assessment (Week 7)
Contentand
Skills
– Synthesis
Landslide Susceptibility Project Structure
*Interim reports are submitted at the end of each exercise. These are edited and included as appendices in the final report
Materials and Supplies• SoilTest Ely Volumeter
• Soil Test Torvane and pocket penetrometer
• Liquid-Limit cups
• Aluminum moisture cans
• Drying oven
• Balance (± 0.001 g)
• Standard surveying equipment
• Shear strength sampling materials and testing apparatus
Laboratory Exercises for
Geotechnical Properties of Soils and Mass Wasting
Nort
h 02 2 4 6 8 10
kilometers
NY
meters
0100 100 200
Example:
Landslide Susceptibility at the Plattsburgh Air Force Base Marina
PAFBmarina
landslide
Saranac River
LakeChamplain
PAFB marina landslide
0 105
meters
North
Contour interval = 1 meter
What factors control slope
processes at the PAFB Marina?
Ele
vatio
n (m
eter
s)
42
40
36
28
34
32
30
38
laminated to thinly bedded marine sand and silt
fossiliferous marine clay
lacustrine varved clay
Massive to ripple cross-laminated
medium to fine sand
diamicton
limestone
water table
colluvium
Approximate extent of
colluvium in 1996
springs
Lake Iroquois breakout deposit
Plattsburgh Air Force Base Marina Section
Lake Champlain
Lake Vermont
ChamplainSea
0 5 10
Horizontal Scale (meters)
Vertical Exaggeration = 2X
West East
Sample No.
Depth Below Top of Section
(m)
Sample Elevation
(m)
Mass Moist
(Mass of Can + Soil +
Water) (g)
Mass Dry
(mass of can + soil)
(g)
Mass of
Can(g)
Sample Volume(cm3)
C1 12.0 30.0 95.15 81.92 37.80 29.15
C2 11.7 30.3 95.16 81.89 38.05 29.15
C3 11.1 30.9 96.00 82.60 38.13 29.15
C4 10.6 31.4 95.75 83.70 36.57 29.15
C5 10.3 31.7 88.11 71.24 37.17 29.15
C6 9.7 32.3 85.59 69.47 38.21 29.15
C7 9.3 32.7 91.97 75.16 38.44 29.15
C8 8.3 33.7 92.12 77.43 38.14 29.15
C9 7.3 34.7 94.95 83.24 36.03 29.15
S1 6.4 35.6 98.91 88.12 38.25 29.50
S2 5.9 36.1 94.61 83.03 36.53 29.50
S3 5.3 36.7 97.36 85.88 38.16 29.50
S4 4.7 37.3 93.15 81.63 37.66 29.50
S5 4.1 37.9 93.66 81.75 36.32 29.50
S6 3.5 38.5 94.57 82.68 37.87 29.50
S7 2.9 39.1 83.90 75.19 30.00 29.50
S8 1.6 40.4 73.41 71.45 30.13 29.50
S9 0.7 41.3 71.80 70.92 30.19 29.50
Elevation at top of section = 42 meters a.s.l.
Gravimetric and Volumetric Data for Glacial Lacustrine and Marine Deposits at the Plattsburgh Air Force Base Marina
16
f
b
sat
1.0 2.21.4 1.8
Soil Density
(g/cm3)(%)
0 6020 40
Porosity (), Vol. Moist. Cont. ()
0 8
Mean(1 error bar)
Particle Size
()
Plattsburgh Air Force Base Marina Section
thinly laminated to
thinly bedded, unfossiliferous, marine fine sand and silt
generally unfossiliferous,
laminated to
thinly bedded, marine
fine sand and silt
calcareous till
thinly laminated
varved lacustrine
clay
fossiliferous, thinly
laminated marine clay
32
38
34
36
42
40
Ele
vatio
n (m
eter
s a.
s.l.)
medium sand
water table
0 168
Mean(1 error bar)
Plattsburgh Air Force Base Marina Section
6040200
LL
n
PL
(Kg/m2)(%)()
630
Torvane Shear Strength
Particle Size Atterberg LimitsWater Content (%)
thinly laminated to
thinly bedded, unfossiliferous, marine fine sand and silt
calcareous till
thinly laminated
varved lacustrine
clay
fossiliferous, thinly
laminated marine clay
32
38
34
36
42
40
Ele
vatio
n (m
eter
s a.
s.l.)
medium sand
water table
generally unfossiliferous,
laminated to
thinly bedded, marine
fine sand and silt
Plattsburgh Air Force Base Marina Section
ChittickCarbonate
Loss on Ignition
840
(%)(%)
Microfauna
(specimens/gram)(3-pt avg., max = 10)
10500 15105
12,990 cal. y.b.p.
Candona Forams
Total
LOI550
LOI1000
Total
Calcite
Dolomite
thinly laminated to
thinly bedded, unfossiliferous, marine fine sand and silt
calcareous till
thinly laminated
varved lacustrine
clay
fossiliferous, thinly
laminated marine clay
32
38
34
36
42
40
Ele
vatio
n (m
eter
s a.
s.l.)
medium sand
generally unfossiliferous,
laminated to
thinly bedded, marine
fine sand and silt
water table
Ele
vatio
n (m
eter
s)
42
40
36
28
34
32
30
38
laminated to thinly bedded marine sand and silt
fossiliferous marine clay
lacustrine varved clay
Massive to ripple cross-laminated
medium to fine sand
diamicton
limestone
water table
colluvium
Lake Iroquois breakout deposit
0 5 10
Horizontal Scale (meters)
Vertical Exaggeration = 2X
West East
Removal of lateral support by beach erosion
Weak, saturated clays
Ground-water sapping at the base of the sand section
Railroad activity (ground vibrations?) and drainage diversions
Seasonal & long-term controls on Lake Champlain
water level
INSTRUCTOR JOINT STUDENT
• Define learning objectives and skills
• Set reasonable expectation levels
• Pose the question
• Provide background information and references
• Articulate workload and final product expectations
• Familiarize yourself with the question – READ LITERATURE!
• Formulate hypothesis(es)
• Design experiments • Define project focus• Plan field work• Assign working
groups and tasks
• Anticipate Contingencies
• Data Collection
• Mentor and Advise
• Data Analysis
• Data Synthesis
Iterative Process
• Assessment• Communicate
Results
PRE-PROJECT
ENDPROJECT
Advantages of Long-Term Projects
• Provides time for students to reflect and contemplate their results–students receive feedback at interim steps;
• Stimulates student interest and creativity;
• Integrates skills and content from discrete exercises;
• Links learning to real-world issues and problems;
• Real data always produce unexpected teaching points that enhance the planned learning activity;
• Engages students in all facets of a project (planning, execution and reporting);
• Reinforces learning from other courses and experiences (e.g. knowledge of regional geology, effective writing mathematics, spreadsheets, and etc.);
• Helps ease the transition from the mindset of student to professional geoscientist.
Summary
Exportability
• Site Availability
May be a problem for some campuses but most activities can be derived from local consultant or municipal case studies.
• Equipment Cost
Small-scale projects can be implemented for
several hundred to a few thousand dollars
• Time Constraints
Macomb Mtn. Landslide, Adirondack Mountains, NY
Additional Slides
• Fall semester residential program featuring 5 inter-related, upper-division undergraduate environmental science and geology classes
• Constructivist pedagogy; emphasis upon small-group, project-based learning
• Day-long course format provides pedagogical flexibility that;
• Creates an informal student-centered learning environment
• Allows seamless integration of lecture instruction and field or laboratory projects
• Facilitates inclusion of long-term projects
• Increases effective geographic range for field excursions
• Affords time for reflection and contemplation
AESP Model:
Rethinking Class Time
Applied Environmental Science Program
SUNY Plattsburgh and The William H. Miner Agricultural Research Institute
Oblique Aerial Photograph
Toe of Slide – Bob Fuller for Scale
Slump at Whallonsburg, NYJuly, 1987
Slump at Whallonsburg, NYJuly, 1987
Jack Ridge Sampling Clay at Head Scarp
Fissures in Overconsolidated Clays at Head Scarp
Toe of Secondary Slump
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