(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
Principles of Geotechnical Engineering (MindTap Course List)
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- A moist soil sample has a total density of 1950 kg/m3, water content of 18%, and specific gravity of solids (Gs) of 2.68. a. Calculate the degree of saturation and voids ratio. b. If the total mass of the sample is 450g, calculate the volume of voids, and the mass of water to be removed if the desired new water content is 12%.arrow_forwardA field unit determination test for the soil, yielded the following data. Moisture content = 12% and moist unit weight = 106 lb/cu.ft. Determine the relative compaction.arrow_forwardA freshly drawn soil core of 10 cm diameter and 5 cm length weighs 700 g. On oven drying at 105°C the core weighs 625 g. Calculate the soil water content on weight and volume basis.arrow_forward
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