(a)
Calculate the dry unit weight of the soil.
(a)
Answer to Problem 3.4P
The dry unit weight of the soil is
Explanation of Solution
Given information:
The diameter of the cylindrical mold
The height of the cylindrical mold
The weight of the compacted soil
The moisture content
The specific gravity of the soil solids
Calculation:
Calculate the volume of the mold
Substitute
Calculate the dry unit weight of the soil
Substitute 4 lb for W,
Hence, the dry unit weight of the soil is
(b)
Calculate the void ratio of the soil.
(b)
Answer to Problem 3.4P
The void ratio of the soil is
Explanation of Solution
Given information:
The diameter of the cylindrical mold
The height of the cylindrical mold
The weight of the compacted soil
The moisture content
The specific gravity of the soil solids
Calculation:
Refer to part (a).
The dry unit weight of the soil
Consider the unit weight of water
Calculate the void ratio of the soil
Substitute 2.72 for
Hence, the void ratio of the soil is
(c)
Calculate the degree of saturation of the soil.
(c)
Answer to Problem 3.4P
The degree of saturation of the soil is
Explanation of Solution
Given information:
The diameter of the cylindrical mold
The height of the cylindrical mold
The weight of the compacted soil
The moisture content
The specific gravity of the soil solids
Calculation:
Refer to part (b).
The void ratio of the soil is 0.568.
Consider the unit weight of water
Calculate the degree of saturation
Substitute 2.72 for
Hence, the degree of saturation of the soil is
(d)
Calculate the additional water needed to achieve
(d)
Answer to Problem 3.4P
The required additional water to achieve
Explanation of Solution
Given information:
The diameter of the cylindrical mold
The height of the cylindrical mold
The weight of the compacted soil
The moisture content
The specific gravity of the soil solids
Calculation:
Refer to part (b).
The void ratio of the soil is 0.568.
Consider the unit weight of water
Calculate the saturated unit weight of the soil
Substitute 2.72 for
Calculate the unit weight
Substitute 4 lb for W and
Calculate the additional water needed to achieve
Substitute
Therefore, the additional water needed is
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Chapter 3 Solutions
EBK PRINCIPLES OF GEOTECHNICAL ENGINEER
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- Fundamentals of Geotechnical Engineering (MindTap...Civil EngineeringISBN:9781305635180Author:Braja M. Das, Nagaratnam SivakuganPublisher:Cengage Learning