Department
of Earth Science Northeastern
Illinois University
INTRODUCTION
TO GEOTECHNICAL ENGINEERING
ESCI
340
Spring,
2007
Review for Exam
#2 (March 15,
2007)
Dr. Sanders
By the end of
today's class, you should be able to do the following:
* (DELETED) Solve
weightvolume
problems that ask you to use the values of some
soil properties to calculate the values of others.
* Using index cards,
construct soil phase diagrams that represent the relative
proportions of mineral, fluid, and gas phases of a soil. Cut the
index cards apart to separate the phases. Please use the
following color scheme:
mass: green cards

weight:
blue cards 
volume:
yellow cards

F (HINT: what is the mass of the gas phase of a soil?)

F (HINT:
what is the weight of the gas phase of a soil?) 
You will need
two volume cards! 
* Using a poster sheet and a pen, arrange the cards to
represent the following properties of soil:
q moisture content (w)
q porosity
(n)
q degree of
saturation (S)
q
unit weight
:
s unit
weight of the soil sample (g)
s unit
weight of water (g_{w})
s dry unit
weight (g_{d})

q density
:
s density of the soil
sample (r)
s dry
density (r_{d})
s density of water
(r_{w})
q specific gravity of
solids (G_{s})
q void ratio (e)
q relative density
(D_{r}) 
* (DELETED) Answer
Practice Problems 4.14.3 (p. 113), 4.6 and 4.7 (p.114).
*
(DELETED) Explain how to derive Equations 4.27, 4.29, and 4.30 in the
textbook
on p. 107.
*
(DELETED) Homework for Thursday: as a group (groups assigned in class)
show how
to derive Equation 4.28.
Laboratory
Determination and Analysis of Grain Size and Plasticity
Lab Methods
* Show how to perform the sieve test portion
of a grain size
distribution analysis (presentation
by Maureen and Evelyn).
* Explain how to use the hydrometer
method to determine the grain size
distribution of the fine portion of a soil sample (presentation by Rob
J and Rob B).
* Explain the use of the term
"percent finer".
Analyzing the
Results; Grain Size Distribution Graphs
*
Looking at a grain
size distribution graph, differentiate between
sediment samples that are poorly graded
and those that are well
graded.
* Using a grain size distribution graph, read off the D_{10}, D_{30},
and D_{60}, and calculate
the coefficient
of uniformity (C_{u}).
* Construct grain size distribution curves for the sample analyses
distributed in class, and those reported
in Problem 4.12 on p. 124.
Fines and
Plasticity
* Explain
the meaning of the engineering term "fines" as it applies to grain
size,
and describe the difference between silt and clay.
* Explain the difference between soil in a liquid, solid, and
semisolid state.
* Explain what the Atterberg limits
of a soil tell us.
* Show how to determine the liquid
limit, plastic limit,
and plasticity index of a
soil sample in the laboratory.
Describing and
Classifying Soils
* Use the ASTM Visual Manual procedure to investigate and
describe the
characteristics of a soil sample (presentation
by Krys and Hossein).
* Use the USDA texture triangle to classify a soil sample.
* Use the
USCS classification system to classify a soil on the basis of
lab tests. (Presentation
by
Jeff.)
* Use the AASHTO classification system to classify a soil sample.
Site Exploration
and Characterization
* Describe the standard methods for characterizing a site in
terms of
its geotechnical aspects. (Presentation
by Matt and Dustin.)
Department
of Earth Science  Northeastern
Illinois
University
© 2007 Laura L. Sanders. Last updated
March 8, 2007.