Geotechnical Engineering

Well Hydraulics

Question 1
Marks : +2 | -2
Pass Ratio : 100%
The parabolic depression in the aquifer is called as __________
Cone of depression and Drawdown curve
Parabolic curve
None of the mentioned
All of the mentioned
Explanation:
The parabolic depression formed when water is pumped from the aquifer through well can be called as cone of depression or the drawdown surface.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
An open well has relatively larger diameter at __________
Base
Middle
Top
Near the bottom
Explanation:
As the velocity of water is larger at the base, the width of base widens up and its diameter increases.
Question 3
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 4
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 5
Marks : +2 | -2
Pass Ratio : 100%
In Recuperation test, the expression (K/A ) is known as ___________
Specific yield and Specific capacity
Coefficient of permeability
None of the mentioned
All of the mentioned
Explanation:
K/A is known as the specific yield or specific capacity of an open well, in cubic meter per hour per square meter of the area through which water percolates.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
Dupuit’s theory was later modified by _________
Thiem
Darcy
Alam Singh
Louden
Explanation:
The theory proposed by Dupuit’s on radial flow was modified by Thiem in 1906.
Question 7
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 8
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 9
Marks : +2 | -2
Pass Ratio : 100%
Specific yield of unconfined aquifer indicates __________
Water capacity
Volume of water
Water retained
All of the mentioned
Explanation:
Specific yield is an indication of the water yielding capacity of an unconfined aquifer.
Question 10
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.