Geotechnical Engineering

Well Hydraulics

Question 1
Marks : +2 | -2
Pass Ratio : 100%
The pumping-in test was devised by _________
U.S. Bureau of soil and PRA
U.S. Bureau of reclamation
Indian standard of Bureau
None of the mentioned
Explanation:
The U.S. bureau of Reclamation (Earth Manual, 1960) has devised two types of pumping-in test.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
Volume of water dv entering the well, when the head recuperates by dh is ___________
dV=A/dh
dV=A.dh
dV=Khdt
dV=K.A
Explanation:
Volume of water entering the well, when the head recuperates by dh is given by the equation: dV=Adh
Question 3
Marks : +2 | -2
Pass Ratio : 100%
When two wells, situated near each other is discharged,the total discharge will __________
Increases
Decreases
Remains the same
None of the mentioned
Explanation:
When two wells are discharged, their drawdown curves intersect within their radii of zero drawdown. Thus the total discharge is increased.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
The value of specific yield SY, of an aquifer depends on ___________
Grain size
Compaction of stratum
Grain shape
All of the mentioned
Explanation:
Since specific yield is the volume of water drained, the drainage of water depend on grain size, shape and compaction of stratum in the soil.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
For fine-grained soil,the value of K/A as specified by Marrio is _________
1.00
0.50
0.25
2.00
Explanation:
For fine-grained type of soil, the value of K/A is 0.25 cubic meter per hour, per sq. m of the area under 1m depression head.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
The co-efficient of transmissibility (T) of an aquifer is given by which of the following equation?
T=b k
T=b/k
T=(b k)2
T=k/b
Explanation:
The coefficient of transmissibility T is equals the field of co-efficient of permeability K multiplied by the aquifer thickness b:
Question 7
Marks : +2 | -2
Pass Ratio : 100%
The type of hydraulics of flows towards open well is __________
Radial flow
Bottom flow
Adjacent flow
All of the mentioned
Explanation:
If the well is open, radial flow takes place all around the well and there is no flow from the bottom of the well.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
The discharge of an open well can be determined by, which of the following method?
Constant head test
Falling head test
Recuperation test
None of the mentioned
Explanation:
In the recuperation test, water level can be depressed to any level and the discharge from the well can be calculated.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
Dupuit’s theory states that, the Darcy’s law equation is not valid near_________
Well face
Top Surface of well
Sides of the well
All of the mentioned
Explanation:
Since the flow of water is not horizontal near wall and the flow no longer remains laminar. Thus, Darcy’s law equation is not valid near the well face.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
According to Dupuit’s theory,the velocity of flow is proportional to__________
Sine of hydraulic gradient
Tangent of hydraulic gradient
None of the mentioned
All of the mentioned
Explanation:
Based on the assumption proposed by Dupuit’s theory, the velocity of flow is proportional to the tangent of the hydraulic agent instead of its sine.