Geotech Flashcards
Ratio of volume of voids and volume of soil.
Porosity
Ratio of volume of voids and volume of soil solids.
Void Ratio
Ratio of volume of water and volume of soil.
None of the above
Which is true for porosity?
0 < n < 100
Which is true for void ratio?
0 < e
Which is true for degree of saturation?
0 ≤ S ≤ 100
When the seepage pressure becomes equal to the pressure due to submerged weight of a soil, the effective pressure is reduced to zero and the soil particles have a tendency to move up in the direction of flow. This phenomenon is generally known:
Quick Condition/Boiling Condition/Quick Sand
What is soil in civil engineering?
The unaggregated and uncemented deposits of minerals and organic particles covering the earth’s crust
If the ground water table in a soil formation rises as resulting of flooding, the bearing capacity of the soil:
Decreases
One of the following foundation conditions does not affect the bearing capacity of the supporting soil.
Load imposed onto the soil
A process by which water-saturated soil sediment temporarily loses strength and acts as a fluid.
Liquefaction
Volume change in saturated soils caused by the expulsion of pore water from loading?
Primary Consolidation
Negative skin friction on piles..
- Is caused due to relative settlement of the soil
- Is caused in soft clays
- Decreases the pile capacity
- All of the above
A decrease in water content results in a reduction of the volume of soil in:
Liquid state, Plastic state, Semi-solid state (All of these)
The water content in a soil sample when it continues to loose weight without loosing the volume, is called
Shrinkage limit
The admixture of coarser particles like sand or silt to clay causes
Decrease in both liquid limit and plasticity index
An index used to identify the swelling potential of clay soils is called
Activity
The property of a soil which permits water to percolate through it
Permeability
Which of the following methods is best suited for determination of permeability of coarse grained soils?
Constant Head Method
Which of the following methods is best suited for determination of permeability of fine grained soils?
Falling Head Method
Terzaghi’s bearing capacity factors Nc, Nq and Nγ are functions of
Angle of internal friction only
Coefficient of earth pressure at rest is: (A). Less than active earth pressure but greater than passive earth pressure (B). Greater than active earth pressure but less than passive earth pressure (C). Greater than both the active earth pressure and passive earth pressure (D). Less than both the active and passive earth pressures
Option B
The average coefficient of permeability of natural deposits: A. Parallel to stratification is always greater than that perpendicular to stratification B. Parallel to stratification is always less than that perpendicular to stratification C. Is always same in both directions D. Parallel to stratification may or may not be greater than that perpendicular to stratification
Option A
The quantity of seepage of water through soils is proportional to: A. Coefficient of permeability of soil / B. Total head loss through the soil / C. Neither A nor B / D. Both A and B
Option D
The critical exit gradient of seepage water in soils, increases with: A. An increase in specific gravity / B. A decrease in specific gravity / C. A decrease in void ratio / D. Both A and C
Option D
Who is the father of modern soil mechanics?
Karl Terzhagi
Rise of water table above the ground surface causes: A. Equal increase in pore water pressure and total stress B. Equal decrease in pore water pressure and total stress C. Increase in pore water pressure but decrease in total stress D. Decrease in pore water pressure but increase in total stress
Option A
The shear strength of a soil: A. Is directly proportional to the angle of internal friction of the soil B. Is inversely proportional to the angle of internal friction of the soil C. Decreases with increase in normal stress D. Decreases with decrease in normal stress
Option D
Effective stress on soil: A. Increases voids ratio and decreases permeability B. Increases both voids ratio and permeability C. Decreases both voids ratio and permeability D. Decreases voids ratio and increases permeability
Option C
The coefficient of compressibility of soil, is the ratio of
strain to stress
What is the largest grain that passes a no. 200 sieve in millimeters?
0.074
Section 302.2.2 of the National Structural Code of the Philippines provides that the slope of cut surfaces of the ground shall be no steeper than is safe for the intended use and shall be no steeper that:
1 to 2
The fraction of soils passing which sieve number is used for Atterberg Limits tests of soils:
40
Coefficient of consolidation of a soil is affected by
Both compressibility and permeability
If the sand in-situ is in its densest state, then the relative density of sand is:
1
Accurate determination of water content, is made by
Oven Drying Method
cobbles
particles with a diameter larger than 75 mm
gravel
particle sizes from 4.75 to 75 mm
sand
particle sizes from 0.075 mm to 4.75 mm
fines
particles smaller than 0.075 mm (silt and clay)
