Essential Tunnel Engineering Objective Questions For Competitive’s

1.In compressed air tunneling, the volume of free air provided is

6 mJ per second per m2 of face area
6 m3 per minute per m2 of face area
20 m3 per minute per m2 of face area
6 m3 per hour per m2 of face area

ANSWER : : 6 m3 per minute per m2 of face area

2.The needle beam method of tunnelling (i) is suitable for soils in which roof can stand for few minutes without support (ii) is suitable for brick lining (iii) is suitable for concrete lining (iv) requires large number of trench jacks Of these statements

only (i) is correct
(i), (ii) and (iv) are correct
(i), (iii) and (iv) are correct
(i) and (ii) are correct

ANSWER : : (i), (ii) and (iv) are correct

3.Assertion A : When rock conditions are favorable, it will not be necessary to take up concrete lining concurrently with the driving operations till the full length of the tunnel has been driven through rock. Reason R : A tunnel through rock, hard or soft, does not need any concrete lining. Select your answer based on the coding system given below:

Both A and R are true and R is the correct explanation of A.
Both A and R are true but R is not the correct explanation of A.
A is true but R is false.
A is false but R is true.

ANSWER : : A is true but R is false.

4.Assertion A : English method of tunneling requires more time as compared to other methods of tunneling. Reason R : In English method of tunneling, the masons and excavators have to work alternately. Select your answer based on the coding system given below :

Both A and R are true and R is the correct explanation of A.
Both A and R are true and R is not the correct explanation of A.
A is true but R is false.
A is false but R is true.

ANSWER : : Both A and R are true and R is the correct explanation of A.

5.What is the correct sequence of the following events of construction of a shaft in rock ? 1 drilling and blasting 2 timbering 3 pumping 4 mucking Select the correct answer usiny the codes given below Codes :

1,2,3,4
1,4,2,3
2,1,4,3
2,4,1,3

ANSWER : : 1,4,2,3

6.Which one of the following is a component of a shield for tunneling ?

liner plate
trench jack
stiffener
cutting edge

ANSWER : : cutting edge

7.Ribs are used for strengthening and stiffening the liner plate for tunnels of diameter greater than

2 m
3 m
4 m
5 m

ANSWER : : 3 m

8.Drift method of tunnelling is used to construct tunnels in

soft grounds
rock
self supporting grounds
broken grounds

ANSWER : : rock

9.Which of the following are percussion drills ? (i) shot drill (ii) diamond drill (iii) wagon drill (iv) churn drill Of these statements

(i) and (ii) are correct
(iii) and (iv) are correct
(i) and (iv) are correct
(ii) and (iii) are correct

ANSWER : : (iii) and (iv) are correct

10.Consider the following situations. # Soil is soft. # Volume of existing surface traffic on the alignment is heavy. # Track is at a deeper level. # Water table is high. In the construction of Metro Railways, “Cut and Cover” method of construction is suitable in situations listed at

1 and 2
1 and 3
1 and 4
2 and 3

ANSWER : s: c

11.Which of the following is not a component of the shield ?

propelling jacks
liner plate
hood
tail

ANSWER : : liner plate

12.The correct sequence of drilling equipment for increasing size of holes in tunnels is

wagon drill, churn drill, shot drill
wagon drill, shot drill, churn drill
shot drill, churn drill, wagon drill
churn drill, wagon drill, shot drill

ANSWER : : wagon drill, churn drill, shot drill

13.In “full face” method of constructing tunnels, the first operation relates to

removal of bottom portion
excavation of one drift in the center
removal of top portion
excavation being done along the periphery

ANSWER : : excavation being done along the periphery

14.Which of the following lining material is useful for shield driven tunnels in sub aqueous regions ?

stone masonry
timber
cast iron
cement concrete

ANSWER : s: c

15.Drifters can be used to drill

only up holes
only down holes
horizontal or up holes
horizontal, down or up holes

ANSWER : : horizontal, down or up holes

16.Which one of the following is considered to be an advantage of the heading and benching method of tunnel construction?

It is suitable for construction in unstable rocks.
In this method, it is easy to install timber support.
Tunnelling can be continuous and the work can be expedited.
In case of excessive water, it is easy to take correct steps.

ANSWER : : Tunnelling can be continuous and the work can be expedited.

17.American method of tunneling i) is suitable for large sized tunnels ii) is no,’ suitable for railway or highway tunnel’s iii) requires heavy timbers Of these statements

only (i) is correct
(i) and (iii) are correct
(ii) and (iii) are correct
(i) and (ii) are correct

ANSWER : : only (i) is correct

18.If ‘N’ is the number of shafts used, then the total number of feces available for attacking the excavation and construction in tunnels are

2N
N + 2
2 N + 1
2 N + 2

ANSWER : : d

19.Which one of the following tunneling methods is used for laying under ground sewers ?

Needle beam method
Army method
German method
Italian method

ANSWER : : Army method

20.A good blast with a good yield is obtained if the cut hole is

normal to face
inclined at 45� to the face
inclined at 15� to the face
inclined at 30� to the face

ANSWER : : inclined at 45� to the face

21.As compared to a single free face, if a charge of explosive is placed equidistant from two faces, then the yield

remains same
decreases
increases by 2.25 times
increases by 3.5 times

ANSWER : : increases by 2.25 times

22.In Belgium method of tunnelling

construction of side walls is completed before invert and roof arch are built.
construction of roof arch is completed before side walls and invert are built.
construction of invert is completed before side walls and roof arch are built.
construction of invert and side walls is completed before roof arch is built.

ANSWER : : construction of roof arch is completed before side walls and invert are built.

23.The most suitable soil for compressed air tunneling is

silt
sand
clay
gravel

ANSWER : : clay

24.If ‘D’ is the diameter of tunnel in metres, then the thickness of lining in mm, as per the empirical formula is given by

42 D
82 D
104 D
124 D

ANSWER : : 82 D

25.Which of the following methods of tunneling is used for long tunnels at great depths ?

Army method
Needle beam method
Austrian method
English method

ANSWER : : Austrian method

26.What is the correct sequence of the following events in rock tunnelling? # marking tunnel profile # loading explosives and blasting # checking misfire # mucking # removing foul gas # setting up and drilling # guniting Select the correct answer using the codes given below. Codes:

1,6,5,3,4,2,7
1,2,6,3,5,4,7
1, 6,2, 5,4, 3, 7
1,6,2,5,3,4,7

ANSWER : : 1,6,2,5,3,4,7