Engineering Questions with Answers - Multiple Choice Questions
MCQs on Trapezoidal Dam as Inclined Side Phase
1 - Question
Calculate the eccentricity of a trapezoidal dam with a distance between the centre of gravity and point where the resultant cuts the base is 5m. The bottom width of the dam is 3m.
a) 2.5m
b) 3.5m
c) 4.5m
d) 5m
View Answer
Answer: b
Explanation: The eccentricity (e) = Z – b/2.
Z= distance between the centre of gravity and point where the resultant cuts the base is 5m.
= 5-3/2 = 1.5m.
2 - Question
Which of the following is not a failure of retaining wall?
a) Structural slide
b) Shear sliding
c) Crushing
d) Slope pitching
View Answer
Answer: c
Explanation: Crushing Failure is related to dams. The retaining walls are the structures constructed to store earth on one side especially in case of hill or ghat roads.
3 - Question
________ pressure which occurs commonly in dams.
a) Passive earth pressure
b) Active earth pressure
c) Soil moisture tension
d) Wind pressure
View Answer
Answer: b
Explanation: Active earth pressure is exerted by backfill on retaining walls. It is also called as practical pressure. It occurs commonly in dams.
4 - Question
_________ failures contribute 40% to earthen dams.
a) Seepage
b) Structural
c) Hydraulic
d) Natural
View Answer
Answer: c
Explanation: On the basis of various investigation reports and case studies, hydraulic failures contribute about 40% of failures to earthen dams. The rest of the failures is shared by seepage failures and structural failures.
5 - Question
Which of the following filters are also known as chimney drains?
a) Horizontal filter
b) Inclined filter
c) Rock toe
d) Toe drain
View Answer
Answer: b
Explanation: The filters which are laid across the outer slope of the impervious core are called as inclined filters. They are also known as Chimney drains. They are provided mainly to collect the seepage emerging out of the core.
6 - Question
Zoned earthen dams are also known as ______
a) Heterogeneous dams
b) Core wall dams
c) Homogeneous dams
d) Hydraulic dam
View Answer
Answer: a
Explanation: The dams are constructed on shallow pervious foundations in this dam section about outer zones are made fairly pervious material and the inner most zoning called “hearting” is done was fairly impervious material. It is also known as heterogeneous dam.
7 - Question
___________ dams are built with key trenches.
a) Heterogeneous earth dam
b) Homogeneous earth dam
c) Earth Dam with Core wall
d) Rolled fill dam
View Answer
Answer: c
Explanation: The outer zones of this dam are made of pervious material as in zoned dam. In this case, it is essentially build cut-off wall (cut-off trench) built quite deep preferably upto impervious rock layer in the foundation.
8 - Question
Line of seepage is also known as __________
a) Hydraulic gradient
b) Phreatic line
c) Seepage gradient
d) Hydraulic seepage line
View Answer
Answer: b
Explanation: The line within the dam section below which there are positive hydrostatic pressures in a dam and above the line the hydrostatic pressures are negative. It gives a divide line between dry and saturated soils.
9 - Question
____________ represents the top stream line.
a) Phreatic line
b) Hydraulic gradient line
c) Seepage gradient
d) Hydraulic seepage line
View Answer
Answer: a
Explanation: Phreatic line is also called a line of seepage or saturation line. The phreatic line represents the top streamline and hence helps us in drawing the flow net.
10 - Question
The hydrostatic pressures on phreatic line are equal to____
a) Zero
b) Maximum
c) Minimum
d) Constant
View Answer
Answer: a
Explanation: The hydrostatic pressure on phreatic line is equal to atmospheric pressure and hence equal to zero, the flow through the body of the dam below the phreatic line reduces the effective weight of the soil and thus reduces the shear strength of the soil.
11 - Question
Expand MWL?
a) Minimum water level
b) Maximum water level
c) Meagre water level
d) Most wind level
View Answer
Answer: b
Explanation: The water level that is attained during floods is called the maximum water level. The dams and spillway sections are designed to withstand water pressure at this level.
12 - Question
______ is the difference of Level between full reservoir level and top of the dam.
a) Net free board
b) Gross free board
c) Design free board
d) Over free board
View Answer
Answer: b
Explanation: In dams, in order to prevent the overtopping during peak floods, a sufficient margin is provided between the full reservoir level and top of the dam. This is known as gross free board.
13 - Question
By keeping the phreatic line within the downstream toe, the ___________ can be avoided.
a) Piping
b) Gullying
c) Sloughing
d) Over topping
View Answer
Answer: c
Explanation: If the filter at downstream side toe is choked then also the downstream too becomes saturated. In such circumstances, some erosion occurs in downstream to this causes sloughing. To avoid this phreatic line must be within the downstream toe.
14 - Question
Springs(closely coiled) are examples of _____________
a) stiffness
b) hardness
c) toughness
d) creep
View Answer
Answer: a
Explanation: The property of a material or substance which offers resistance to bending action and measures the load required to be applied is called stiffness. It is denoted by s or k. Springs are the best examples of stiffness.
15 - Question
Perennial canals are also known as ________
a) Inundation canal
b) Productive canal
c) Feeder canal
d) Permanent canal
View Answer
Answer: d
Explanation: The canal which is fed by a permanent source of supply is said to be a permanent Canal. It has also regulatory works. This canal is also sometimes known as a perennial canal.