WorksheetsSoil Composition and Basic Weight-Volume Definitions
Total questions: 28
Worksheet time: 24mins
Using the phase diagram notation, which expression correctly represents total volume VT of a soil mass?
VT = Va + Vw + Vs
VT = Ww + Ws
VT = Va + Ww + Ws
VT = Vv − Vs
From the phase diagram, what is the weight of air in the soil column?
Equal to WT
Equal to Ws
Equal to Ww
Zero weight
Moisture Content is defined as
w = Ws / Ww
w = Ww / WT
w = Ww / Ws
w = WT / Ww
A sand specimen has Vs = 500 cm³ and VT = 1000 cm³. Compute the void ratio e.
Typical ranges are shown for void ratios. Which statement best compares sands and clays?
Sands often 0.4–1.0; clays typically 0.3–1.5
Sands often 0.3–1.5; clays typically 0.4–1.0
Sands often 1.5–3.0; clays typically 0.1–0.2
Sands often 0.1–0.2; clays typically 2.0–3.5
In a soil phase diagram, the degree of saturation S is defined as
S = Vw / VT × 100%
S = Vv / VT × 100%
S = Ws / Ww × 100%
S = Vw / Vv × 100%
What is the degree of saturation for a dry soil?
S = 100%
S = 50%
S = 0%
S = 25%
Water content w is defined as the ratio of the weight of water to the weight of soil solids times 100%. Which statement is most accurate about w?
It is based on volumes, not weights
It can exceed 100% in certain clays
It cannot exceed 100% by definition
It equals the degree of saturation
In the illustrated soil column with equal volumes of air and water in the voids, the void ratio is given as e=1.0. If the volume of solids is 0.5 m3, what is the total volume of water Vw?
0.25 m3
0.75 m3
0.50 m3
1.00 m3
Using the same column, what are the porosity n and degree of saturation S of this soil?
n= 25%, S=50%
n= 50%, S=50%
n= 50%, S=100%
n= 25%, S=25%
The specific gravity of a soil Gs is defined as (a) .
A saturated soil sample has total volume VT = 0.20 m3 and total weight WT = 3.6 kN. Calculate its total unit weight γT and choose the correct value.
16 kN/m3
18 kN/m3
12 kN/m3
9 kN/m3
Which expression correctly defines dry unit weight for this sample?
γd = WT / VT
γd = Ws / Vs
γd = Ws / VT
γd = Ww / Vv
You are asked to compare two identical soils: one dry and one fully saturated. Which change best explains why the saturated unit weight is greater?
Solids weight Ws increases with saturation
Air removal reduces total volume VT
Void ratio e decreases to zero
Added water increases total weight WT
A soil element has Vs = 1 m3, void ratio e = 0.8, and degree of saturation S = 0.75. Using the phase relations, compute the water content w. Assume Gs = 2.65. Show your reasoning and final value.
A soil specimen has total volume VT = 1 m3, porosity n, and degree of saturation S. Which expression correctly gives the water volume Vw in terms of n and S ?
Vw equals n divided by S
Vw equals S times n
Vw equals S divided by n
Vw equals one minus S n
For a soil with VT = 1 m3, solids specific gravity Gs and water unit weight γw, the dry unit weight γd is derived as which expression?
γd equals Gsγw(1 − n)
γd equals Gsγw(1 + ω)
γd equals γwSn over Gs
γd equals Gs(1 − n) over γw
A soil layer has porosity n and water mass Ww. If solids mass Ws = Gs γw (1 − n), what is the water content w in terms of S, n, and Gs?
A soil problem gives void ratio e and water content w. Which setup best supports solving unknowns using a phase diagram?
Assume VT equals 2 cubic meters and estimate entries
Assume air volume equals 1 cubic meter and ignore entries
Assume Vw equals 1 cubic meter and skip entries
Assume Vs equals 1 cubic meter and fill entries
A sand has Gs = 2.65 and n = 0.35. Using γd = Gsγw(1 − n) / (1 + e) is incorrect. Choose the correct dry unit weight formula from the table given these variables.
γd = Gsγw(1 − n)
γd = (Gs + n)γw
γd = Gsγw / (1 + n)
γd = Gsγw(1 − n) / (1 − e)
Given wet mass 174.2 g and dry mass 148.4 g for the specimen, compute the water mass in grams.
(a)
Compute the water content w as a percentage using masses above. Provide value to one decimal place in %.
(a)
For Gs = 2.71 and γw = 9.81 kN/m³, compute Ws in kN for Vs = 1 m³. Provide value to two decimal places.
(a)
For a saturated soil, using Ww = 4.625 kN and γw = 9.81 kN/m³, compute void volume Vv in m³. Provide value to two decimal places.
(a)
Compute degree of saturation S in % using Vw = 0.47 m³ and Vv = 0.57 m³. Provide value to one decimal place.
(a)
If the oven-dry mass were 150.0 g instead of 148.4 g, what happens to w?
w decreases
w increases
w remains unchanged
w becomes undefined
If Vw remains 0.47 m³ but air occupies 0.20 m³, compute S in %. Provide value to one decimal place.
(a)
A geotechnical lab estimates e = 0.95, Gs=2.7 and natural moisture content near 22% for a wind-deposited silt–sand. The degree of Saturation in % of this soil is
(a)
