GEO TERMS: FLOW OF WATER THROUGH SOIL Flashcards
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
A. parallel to stratification is always greater than that
perpendicular to stratification
physical properties of a permeant which influence permeability are _____
A. viscosity only
B. unit weight only
C. both viscosity and unit weight
D. none of the above
C. both viscosity and unit weight
the coefficient of permeability of soil _____
A. does not depend upon temperature
B. increases with the increase in temperature
C. increases with the decrease in temperature
D. none of the above
B. increases with the increase in temperature
during seepage through a direction of seepage is always _____
A. parallel to equipotential lines
B. perpendicular to stream lines
C. perpendicular to equipotential lines
D. none of these
C. perpendicular to equipotential lines
the seepage force in a soil is _____
A. perpendicular to equipotential lines
B. proportional to the exit gradient
C. proportional to the head loss
D. all the above
D. all the above
Stoke’s law is valid only if the size of particle is _____
A. less than 0.0002 mm
B. greater than 0.2 mm
C. between 0.2 mm and 0.0002 mm
D. all of the above
C. between 0.2 mm and 0.0002 mm
pick up the correct statement from the following:
A. the permeability of the coarse grained soils may be reduced by grouting
B. the process of injecting fluids (i.e. grouts) into the pores space of the soil is called grouting
C. the grouting increases the soil strength
D. all the above
D. all the above
select the correct statement:
A. the greater the viscosity, the greater is permeability
B. the greater the unit weight, the greater is permeability
C. the greater the unit weight, the smaller is permeability
D. unit weight does not permeability
B. the greater the unit weight, the greater is permeability
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
D. both A and B
the critical exist 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
D. both A and C
Stoke’s law states that the velocity at which a grain settles out of suspension, the other factors remaining constant is dependent upon _____
A. shape of grain
B. weight of grain
C. size of grain
D. shape, size and weight of grain
D. shape, size and weight of grain
the phreatic line in an earth dam may be _____
A. circular
B. elliptical
C. parabolic
D. a straight line
C. parabolic
in a flow net…
A. flow lines and equipotential lines cross each other at right angles
B. fields are rectangles whose length is twice the breadth
C. smaller the dimensions of the field, smaller will be the hydraulic gradient and velocity of flow through it
D. for homogeneous soil, the curves are smooth and circular
A. flow lines and equipotential lines cross each other at right angles
which of the following methods is more suitable for the determination of permeability of clayey soil?
A. constant head method
B. falling head method
C. horizontal permeability test
D. none of the above
B. falling head method
if Nf, Nd, and H are total number flow channels, total number of potential drops and total hydraulic head differences respectively, the discharge q through the complete flow is given by (where K is a constant)
A. q = √H (Nf/Nd)
B. q = KH (Nd/Nf)
C. q = KH (Nf/Nd)
D. q = KH √(Nf/Nd)
C. q = KH (Nf/Nd)
a critical hydraulic occur when _____
A. flow is in upward direction
B. seepage pressure is in upward direction
C. effective pressure is zero
D. all the above
D. all the above
which of the following methods is best suited for determination of permeability of coarse-grained soils?
A. constant head method
B. falling head method
C. both the above
D. none of the above
A. constant head method
if there is no impervious boundary at the bottom of a hydraulic structure, stream lines tend to follow _____
A. a straight line
B. a parabola
C. a semi-ellipse
D. a semi-circle
C. a semi-ellipse
flow net is used for the determination of _____
A. quantity of seepage
B. hydrostatic pressure
C. seepage pressure
D. all the above
D. all the above
Stoke’s law does not hold good if the size of particle is smaller than _____
A. 0.0002 mm
B. 0.002 mm
C. 0.02 mm
D. 0.2 mm
A. 0.0002 mm
quick sand is a _____
A. type of sand
B. flow condition occurring in cohesive soils
C. flow condition occurring in cohesionless soils
D. flow condition occurring in both cohesive and cohesionless soils
C. flow condition occurring in cohesionless soils
the total discharge from two wells situated near to each other is _____
A. sum of the discharges from individual wells
B. less than the sum of the discharges from individual wells
C. greater than the sum of the discharges from individual wells
D. equal to larger of the two discharges from individual wells
B. less than the sum of the discharges from individual wells
the property of a soil which permits water to percolate through it is called _____
A. moisture content
B. permeability
C. capillarity
D. none of these
B. permeability
the critical exist gradient of seepage water in soils is _____
A. directly proportional to the voids ratio
B. inversely proportional to the specific gravity
C. directly proportional to the specific gravity
D. none of these
C. directly proportional to the specific gravity
Darcy’s law is applicable to seepage id a soil is _____
A. homogenous
B. isotropic
C. incompressible
D. all of the above
D. all of the above
pick up the correct statement from the following:
A. the phenomenon of quicksand generally occurs in the cohesionless soil
B. at critical hydraulic gradient, the saturated sand becomes quick
C. the critical gradient depends on the void ratio and the specific gravity
D. all of the above
D. all of the above
