sample problems with solved answers. very useful for practice solvingFull description
Answers to questions about liquid limit, the liquid limit test, using the attenberg device, etc.Full description
soil mechanics
Descripción completa
Chen W.F Mizuno E.
Chen W.F Mizuno E.
INTRODUCTION TO SOIL MECHFull description
SOIL MECHANICS LABORATORY MANUAL
introduction for soil mechanicsFull description
Title
Mehanika tla
Advanced Soil Mechanics by B.M.das
mnbmnbmbmDescription complète
Full description
Soil Mech
Basic and Applied Soil Mechanics Gopalranjan And ASR RaoDescripción completa
Basic and Applied Soil Mechanics Gopalranjan And ASR RaoFull description
mnbmnbmbmDescripción completa
Soil Mechanics Reviewer for Civil engineering
CHAPTER 1: SOIL PROPERTIES
The total volume of a given soil sample can be expressed as: =
+
=
+
+
Where: V V V V
= volume of soil soil solids = volume volume of voids voids = volume volume of of water water in the the void voidss = volume volume of air air in the the voids voids
Assume that the weight of air is negligible, the total weight of the sample as: =
+
where: W = weight of soil soilds soilds W = weig weight ht of wa wate terr
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Phase Relationships: The water content or moisture content (w) is the ratio of the weight of water to the weight of soil solids, i.e. w=
W W
The degree of saturation or saturation ratio (S) is the ratio of the volume of water to the total volume of void spaces, i.e. =
The degree of saturation can range between the limits of zero for a completely dry soil and one (or 100%) for a fully saturated soil.
The void ratio (e) is the ratio of the volume of voids to the volume of soil solids, i.e. =
The porosity (n) is the ratio of the volume of voids to the total volume of soil, i.e. =
As V = V + V , void ratio and porosity are interrelated as follows: =
1−
and =
1+
The specific volume (v) is the total volume which contains a unit volume of solids, i.e. =
=1+
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The air content or air void ratio (A) is the ratio of volume of air to the total volume of soil, i.e. =
The bulk unit weight (γ) of a soil is the ratio of the total mass to the total volume, i.e. =
The specific gravity of the soil particles (G s) is given by =
=
where ρs is the particle density.
Other important relationships are listed below:
=
= −
= (1 − )
;
1+
+
=
1+
For a completely dry soil (S = 0): =
1+
For a completely saturated soil (S = 1): =
+ 1+
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The relative density (I D) is used to express the relationship between the in-situ void ratio (e), or the void ratio of a sample, and the limiting values e max and emin representing the loosest and densest possible soil packing states respectively. The relative density is defined as: 1 =
− −
=
(
)
1 (
)
−
1
−
1 (
)
Thus, the relative density of a soil in its densest possible state (e = emin) is 1 (or 100%) and in its loosest possible state (e = e max) is 0.
Direction: Select the correct answer for each of the following questions. Mark only one answer for each item by shading the circle corresponding to the letter of your choice on the answer sheet provided. No solution, no credit points. Erasures means wrong.
1. A soil sample weighs 14.46 N and has a volume of 0.000991 m3. The specific gravity is 2.65. The volume of air is 0.000167 m 3. Find the dry unit weight of the original soil sample (kN/m 3). A. 15.62 C. 10.24 B. 13.25 D. 17.85 2. Soil solids have a specific gravity of 2.71. Find the unit weight of the solids in SI units (kN/m 3). A. 26.6 C. 169.1 B. 27.1 D. 2.71 Situation 1: A mold having a volume of 0.10 ft 3 was filled with moist soil. The weight of the soil in the mold was found to be 12.00 lb. The soil was oven-dried and the weight after drying was 10.50 lb. The specific gravity of solids was known to be 2.70. 3. Determine the water content. A. 12.5% C. 38.6% B. 14.3% D. 24.0% 4. Find the void ratio. A. 0.605 C. 0.143 B. 0.386 D. 0.377 5. Find the porosity. A. 0.604 C. 0.143 B. 0.386 D. 0.377 6. Find the degree of saturation. A. 14.3% C. 63.8% B. 100% D. 24.0% 7. Find the total unit weight (lb/ft3). A. 120 C. 165 B. 105 D. 62.4 8. Find the dry unit weight (lb/ft3). A. 120 C. 165 B. 105 D. 62.4
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Situation 2: One cubic meter of wet soil weighs 19.80 kN. If the specific gravity of soil particles is 2.70 and water content is 11%: 9. Find the void ratio. A. 0.558 C. 0.485 B. 0.425 D. 0.510 10.Find the dry unit weight (kN/m 3). A. 17.84 C. 18.85 B. 18.03 D. 16.54 11.Find the degree of saturation (%). A. 0.613 C. 0.582 B. 0.532 D. 0.700 Situation 3: From the following data of a soil sample: Sample size 3.81 cm dia. × 7.62 cm ht. Wet weight = 1.668 N Oven-dry weight = 1.400 N Specific gravity = 2.70 12.Determine A. 19.55 B. 17.25 13.Determine A. 16.12 B. 16.55 14.Determine A. 19.79 B. 19.20 15.Determine A. 0.445 B. 0.587 16.Determine A. 82.55% B. 80.31%
the water content (%). C. 18.68 D. 19.14 the dry unit weight (kN/m 3). C. 14.68 D. 16.21 the bulk unit weight (kN/m 3). C. 19.01 D. 19.24 the void ratio. C. 0.611 D. 0.644 the degree of saturation (%). C. 79.34% D. 74.72%
17.A soil has bulk density of 20.1 kN/m 3 and water content of 15%. Calculate the water content (%) if the soil partially dries to a density of 19.4 kN/m 3 and the void ratio remains unchanged.
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A. 11% B. Choice B
C. Choice C D. Choice D
Situation 4: The porosity of a soil sample is 35% and the specific gravity of its particles is 2.70. 18.Calculate its void ratio. A. 0.54 C. 0.44 B. 0.26 D. 0.33 19.Calculate its dry unit weight. A. 18.39 C. 21.02 B. 19.92 D. 17.22 20.Calculate the saturated unit weight. A. 23.05 C. 20.65 B. 21.39 D. 22.35 21.Calculate the submerged unit weight. A. 13.24 C. 10.84 B. 11.58 D. 12.54 22.Given the phase diagram shown, what is the most nearly value of the porosity?
A. 0.42% B. 3.3%
C. 9.1% D. 30.20%
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23.The mass specific gravity of a fully saturated specimen of clay having a water content of 30.5% is 1.96. On oven drying, the mass specific gravity drops to 1.60. Calculate the specific gravity of clay. A. 2.50 C. 2.65 B. 2.70 D. 2.77 24.A soil sample with a grain specific gravity of 2.67 was filled in a 1000 ml container in the loosest possible state and the dry weight of the sample w as found to be 14.75 N. It was then filled at the densest state obtainable and the weight was found to be 17.70 N. The void ratio of the soil in the natural state was 0.63. Determine the density index in the natural state. A. 49.25% C. 45.22% B. 59.25% D. 55.11% 25.The dry unit weight of a sand sample in the loosest state is 13.34 kN/m 3 and in the densest state, it is 21.19 kN/m 3. Determine the density index of this sand when it has a porosity of 33%. Assume the grain specific gravity as 2.68. A. 0.511 C. 0.655 B. 0.605 D. 0.525
