Civil Engineering - UPSC Civil Service Exam Questions MCQs Part 24

1. For Froude number of a hydraulic jump is 5.5. The jump can be classified as a/an:

A.
undularjump
B.
oscillating jump
C.
weak jump
D.

2. A cantilever pin-jointed truss carries one load P at the point Z as shown in the given figure. The hinges in the vertical wall are at A and D. The truss has only three horizontal members AC, CG and GZ.The nature of force in member AB

A.
is tensile
B.
is zero
C.
is compressive
D.
cannot be predicted

3. A saturated stiff clay has unit weight 2 gm/cm3 and unconfined compressive strength 2 kg/cm2. The depth of tension crack that would develop in this clay is

A.
2 m
B.
5 m
C.
10 m
D.
20 m

4. Consider the following statements :1. In a member subjected to uniaxial tensile force the maximum normal stress is the external load divided by the maximum cross-sectional area.2. When the structural member is subjected to uniaxial loading, the shear stress is zero on a plane where the normal stress is maximum.3. In a member subjected to uniaxial loading, the normal stress on the planes of maximum shear stress is less than the maximum.Of these statements :

A.
1 and 2 are correct
B.
1 and 3 are correct
C.
2 and 3 are correct
D.
1, 2 and 3 are correct

5. .The displacement thickness of a boundary layer is

A.
The distance to the point where (v/V) = 0.99
B.
the distance where the velocity v is equal to the shear velocity V∗ that is where v = V∗
C.
the distance by which the main flow is to be shifted from the boundary to maintain the continuity equation
D.
one-half the actual thickness of the boundary layer

6. The axial load which just produces the condition of elastic instability in a column is

7. If R is the radius of the circular railway curve in metres and D is the degree of the curve, then which one of the following is the expression for D ?

A. D = 360/R
B. D = 1080/R
C. D = 1720/R
D. D = 720/R

8. Given below are methods of compaction :1. Vibration technique 2. Flooding the soil 3. Sheeps-foot roller 4. Tandem roller5. Heavy weights dropped from a height.The methods suitable for cohesionless soils include

A. 1, 2 and 3
B. 2, 3 and 4
C. 1, 2 and 5
D. 3, 4 and 5

9. The ratio of torsional moments of resistance of a solid circular shaft of diameter D and a hollow shaft having external diameter D and internal diameter d is given by

A.
B.
C.
D.

10. Consider the following statements relating to triaxial tests :1. Change in length of the specimen in a triaxial shear test is required to be accounted for in the calculation of stresses at failure.2. In 'Drained Triaxial Shear Test', drainage is permitted under a specified all-round pressure until consolidation is complete. The principal stress difference is then applied with no drainage being permitted.3. Unconfined compression test is a special case of triaxial shear test.Of these statements :

A. 1 and 2 are correct
B. 1 and 3 are correct
C. 2 and 3 are correct
D. 1, 2 and 3 are correct

11. The given figure shows the arrow diagram for a particular project. The arrow 'A' is known as

A. critical activity
B. sub-critical activity
C. logic arrow
D. dummy activity

12. In a plane strain problem in XY plane, the shear strain = 12 x 10-6, and the normal strain in X and Y direction = 0, For this state of strain, what is the diameter of the Mohr's Circle of strain ?

A. 6 x 10-6
B. 8 x 10-6
C. 12 x l0-6
D. 24 x l0-6

13. A horizontal fixed beam is fixed at both it ends A and B. During loading, the right support sinks by an amount δ. Flexural rigidity of the beam is uniform and is equal to EI. Length of the beam is L. What is the moment developed at the centre of the beam due to sinking of the support ?

A. 6 EI δ/L2
B. zero
C. 3 EI δ/L2
D. 12 EI δ/L2

14. A lighthouse is visible just above the horizon at a certain station at the sea level. The distance between the station and the lighthouse is 40 km. The height of the lighthouse is approximately

A. 187 m
B. 137.7 m
C. 107.7 m
D. 87.3 m

15. Which of the following are the additional moments considered for design of slender compression member in lieu of deflectiion x and y directions ?(Where Pu is axial load; lex and ley are effective lengths in respective directions; D depth of section ⊥ to major axis; b width of the member)

A.
B.
C.
D.

16. A close-coiled helical spring has 100 mm mean diameter and is mada of 20 turns to 10 mm diameter steel wire. The spring carries an axial load of 100 N Modulus of rigidity is 84 GPa. The shearing stress developed in the spring in N/mm2 is

A. 120/π
B. 160/π
C. 100/π
D. 80/π

17. Consider the following statements pertaining to plane table survey :1. Two-point problem is solved by mechanical method.2. Three-point problem is solved by Bessel's method.3. In two point problem, auxiliary station is required.Of these statements :

A. 1 and 2 are correct
B. 1 and 3 arc correct
C. 2 and 3 are correct
D. 1, 2 and 3 are correct

18. If a member is subjected to tensile stress of px, compressive stress of py and tensile stress of pz along the x, y and z directions respectively, then the resultant strain 'ex' along the 'x' direction would be (E is Young's modulus of elasticity, μ is Poisson's ratio)

A.
B.
C.
D.

19. A cantilever is subjected to a uniformly distributed load W over its whole length 'L' and a concentrated upward force W at its free end. The deflection of the free end is

A. zero
B.
C.
D.

20. The local sidereal time (LST) is always

A. ahead of the local mean time (LMT) by about 2 hours per month
B. behind LMT by about 2 hours per month
D. equal to LMT

21. Consider the following statements :I: To insert a 28 mm nominal diameter rivet, 29.5 mm rivet hole is made.II: Provision is made to allow temperature expansion of the bolt.

A. both I and II are true
B. I is true but II is false
C. I is false but II is true
D. both I and II are false

22. Consider the following statements :A : For beams, I-sections are more economical than rectangular section. R : Most of the material is concentrated away from the centroid. Of these statements :

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is try but R is false
D. A is false but R is true.

23. Two different granular soils are placed in a permeameter tube and flow is allowed to take place under a constant total head. The total head and pressure head at point A in centimeters, are respectively.

A. 75, 75
B. 25, 75
C. 25, 25
D. 75, 25

24. When the degree of consolidation is 50%, the time factor is about

A. 0.2
B. 0.5
C. 1.0
D. 2.0

25. General shrinkage in cement concrete is caused by

A. carbonation
B. stresses due to external load
C. drying the starting with a stiff consistency
D. drying starting with a wetter consistency.

26. The distribution system configuration shown in the following figure is called

B. grid iron system
D. ring system

27. The phenomenon of reflection cracking is observed in which of the following ?

A. Bituminous overlays provided over cracked cement concrete pavements
B. Cement concrete overlays provided over cracked bituminous pavements.
C. Bituminous overlays constructed in cold weather
D. Cement concrete overlays provided over cement concrete pavements.

28. What are the gases produced by landfills primarily comprised of?

A. Carbon monoxide and hydrogen sulphide.
B. Methane and carbondioxide
C. Sulphur dioxide and nitrogendioxide
D. Ethane and oxygen.

29. Consider the following statements regarding specific energy of flow in an open channel :1. There is only one specific energy curve for a given channel.2. Alternate depths are the depths of flow at which the specific energy is the same.3. Critical flow occurs when the specific energy is minimum.Of these statements :

A. 1 and 2 are correct
B. 1 and 3 are correct
C. 2 and 3 are correct
D. 1, 2 and 3 are correct

30. A motor shaft rotating with a speed of 90 rpm decelerates uniformly when the motor is switched off and stops in 40 sec. The number of revolutions made by the shaft in this time would be

A. 10
B. 20
C. 30
D. 40

31. Which one of the following statements is correct ?The portal method of structural analysis is generally suitable for

A. tall buildings
B. low-rise buildings
C. low-rise buildings with uniform framing
D. low-rise buildings with non-uniform framing.

32. How high should a helicopter pilot rise at a point. A just to see the horizon at point B, if the distance AB is 40 km ?

A. 101.75 m
B. 110.50 m
C. 107.75 m
D. 105.50 m

33. A cantilever beam 'A' with rectangular cross-section is subjected to a concentrated load at its free end. If width and depth of another cantilever beam 'B' are twice those of beam A, then the deflection at free end of the beam 'B' as compared to that of 'A' will be

A. 6.25%
B. 14%
C. 23.6%
D. 28%

34. A bar of square section is subjected to a pull of 10000 kg. If the maximum allowable shear stress on any section is 500 kg/cm2, then the side of the square section will be

A. 5 cm
B. 10 cm
C. 15 cm
D. 20 cm

35. A clay sample has a void ratio of 0.54 in dry state. The specific gravity of soil solids is 2.7. What is the shrinkage limit of the soil ?

A. 8.5%
B. 10.0%
C. 17.0%
D. 20.0%

36. Consider the following statements related to Los Angeles Abrasion test on aggregates :1. It evaluates hardness of source - rock2. It has a coefficient of variation of about 30 percentWhich of the statements given above is/are correct ?

A. 1 only
B. 2 only
C. Both 1 and 2
D. Neither 1 nor 2

37. A bar of uniform cross-section of 400 mm2 is loaded as shown in the figure. The stress at section 1-1 is

A. 50 N/mm2
B. 100 N/mm2
C. 25 N/mm2
D. 200 N/mm2

38. Due to settlement of support at A of propped cantilever shown in the figure given below, what is the vertical reaction at B ?

A.
B.
C.
D.

39. A wooden plank (sp. gr. 0.5) 1 m x 1 m x 0.5 m floats in water with 1.5 kN load on it with 1 m x 1 m surface horizontal. The depth of plank lying below water surface shall be

A. 0.178 m
B. 0.250 m
C. 0.403 m
D. 0.500 m

40. A parabolic vertical curve is to be set out connecting two uniform grades of +0.6% and +.0%. The rate of change of grade is to be 0.06% per 30 m. The length of the curve will be

A. 66 2/3 m
B. 133 1/3 m
C. 200 M
D. 266 2/3 m

41. For an activity 201-207 in an AOA network, the EET values, LET values and activity duration are shown in the figure. Between free float, interference float and independent float, which one of the following is the correct sequence in the decreasing magnitude order ?

A. Free float - Interference float - Independent float
B. Free float - Independent float - Interference float
C. Interference float - Free float - Independent float
D. Interference float - Independent float - Free float

42. Consider the following statements :1. Dock is a marine structure for mooring up vessels, loading and unloading of passengers and/or cargo.2. Dry dock is generally used only for carrying out repairs, inspections and painting.3. Wet dock is an enclosed or partially enclosed basin provided with locks and entrance gate to keep the water level at a fairly constant level.Which of the statements given above are correct ?

A. 1, 2 and 3
B. 2 and 3
C. 1 and 2
D. 1 and 3

43. Which one of the following statements is true to trickling filter sludge ?

A. It has a comparatively low sludge volume index
B. It is more difficult to dewater than activated sludge
C. It has a comparatively low concentration of sludge solids
D. It is bulky

44. In the case of a column of length 'l', moment of inertia of cross-section 'I' and Young's modulus of the material of the column 'E' being hinged at both ends, the buckling load, according to Euler's colum

A.
B.
C.
D.

45. What is the correct sequence of the following steps in the graphical determination of stresses in the members of a loaded plane truss ?1. Vector diagram to determine the end reactions.2. Space diagram.3. Stress diagram.Select the correct answer using the codes given below :

A. 1, 2, 3
B. 1, 3, 2
C. 2, 1, 3
D. 2, 3, 1

46. A steel rod of 16 irim diameter has been used as a tie in a bracing system, but may subject to possible reversal of stress due to the wind. What is the maximum permitted length of the member ?

A. 1600 mm
B. 1400 mm
C. 1200 mm
D. 1000 mm

47. The total number, of independent equations that form the Lacey's regime theory is

A. 2
B. 3
C. 4
D. 6

48. The following methods are used for structural analysis :1. Macaulay method 2. Column analogy method3. Kani's method 4. Method of sectionsThose used for indeterminate structural analysis would include

A. 1 and 2
B. 1 and 3
C. 2 and 3
D. 2, 3 and 4

49. In the case of S2 water surface profile (y = depth of flow, y0 = normal depth, yc = critical depth)

A. y0 > yc > y
B. yc > y0 > y
C. yc > y > y0
D. y > yc > y0

50. A summit vertical curve is to be set joining + 2 percent grade with -3 percent grade. If the tangents interest at an elevation of 60 m and the rate of change of grade is - 1 percent per 100 m, then the elevation of the beginning point of the vertical curve will be

A. 58.5 m
B. 57.5 m
C. 55.0 m
D. 52.5 m