3-37
3-38
3-39
What is the value for D30 for this
soil sample?
1.
3.0
2.
4.8
3.
5.6
4.
6.2
What is the coefficient of
curvature (Cc) of this soil sample?
1.
5.6
2.
12.7
3.
21.9
4.
52.0
What is the classification of this
soil sample?
1. GW
2. GP
3. SW
4. SP
Learning Objective: Identify the
test procedures used in the field
to identify soil characteristics.
3-40.
Why is it also necessary to perform
field identification tests on soils
even when laboratory tests are
required during soil explorations?
1.
To determine which laboratory
tests will be omitted
2.
To minimize the duplication of
laboratory tests samples
3.
To provide duplicate results
for positive identification
4.
To ensure there are no errors
in the laboratory tests
3-41.
What is the best way to gain the
necessary skills required for field
testing?
1.
By working with experienced
technicians
2.
By receiving formal soils
training
3.
By getting the “feel” of the
soil during the laboratory
tests
3-42.
What is the most useful tool for
performing field identification
tests?
1.
A hand auger
2.
A scale or balance
3.
A No. 40 sieve
4.
A No. 200 sieve
3-43.
3-44.
3-45.
3-46.
3-47.
3-48.
When identifying soils in the
field, which of the soil properties
should you include in the
description of the soil?
1.
Color
2.
Percentage of sand
3.
Maximum particle Size
4.
Particle shape
Visual examination is used to
establish which of the following
properties of the soil?
1.
Color
2.
Grain distribution
3.
Cohesiveness of the soil
4.
Grain shape of the fines
When the color of a soil has been
identified through a visual
examination, what other data should
you note regarding the soil
condition at the time of
identification?
1.
Temperature
2.
Maximum particle size
3.
Chemical content
4.
Moisture content
During visual examination of a soil
sample, you notice a yellow color.
What can you conclude about the
soil from this observation?
1.
Organic material is present
2.
Iron oxides are present
3.
The soil has poor drainage
capabilities
4.
Aluminum compounds are present
What is the first step in
approximating grain-size
distribution in field
identification?
1.
Separating the larger particles
2.
Examining the coarse-grained
soil for gradation distribution
3.
Estimating the percentage of
fine-grained soil
4.
Performing the sieve sampling
You have determined the soil to be
coarse-grained and estimated the
fines to be 4 percent. What is the
soil classification of the soil?
1. GW-GM
2. SW-SM
3. GC
4. Gravel or sand, depending on
additional information
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