### Civil Engineering - UPSC Civil Service Exam Questions MCQs Part 27

1. Vibratory rollers are more useful for compacting which of the following ?

A.
Sandy soils
B.
Silty soils
C.
Clayer soils
D.
Mixed soils

2. What does the wind Rose Diagram (WRD) for orientation of airport runway give ?

A.
Direction of wind
B.
Direction and duration of wind
C.
Direction, duration and intensity of wind
D.
None of the above

3. The head loss caused due to sudden expansion of pipe from area A1 to area A2 and the velocity from V1 to V2 is given by

A.
B.
C.
D.

4. A simply supported continuous beam with two equal spans carries uniformly distributed load w on entire length of the beam. If each span has a length L, the bending moment at the central support is

A.
B.
C.
D.

5. Which one of the follewing represents a circumpolar star ?

A.
Upper culmination above horizon, lower culmination below horizon
B.
Both upper and lower culminations below horizon
C.
Both upper and lower culminations above horizon
D.
Altitude at upper culmination is minimum

6. What is the ratio of maximum shear stress to average shear stress for a circular section ?

A. 2
B.
C.
D.

7. If a circular shaft is subjected to a torque T and a bending moment 'M' the ratio of the maximum shear stress to the maximum bending stress is given by :

A. 2M/T
B. T/2M
C. 2T/M
D. M/2T

8. Which one of the following statements is not correct ?

A. Models are always smaller than the prototypes.
B. Dynamic similarity between a model and a prototype can be verified by equating Reynold's number in a viscous flow.
C. Mach number achieves significance when the velocity of fluid approaches or exceeds the sonic velocity.
D. Distorted models are always exaggerated on a vertical scale.

9. The construction of impounding reservoir is required when

A. average annual flow in the stream is lower than average demand
B. the rate of flow in the stream, in dry season in more than the demand
C. the rate of flow in the stream, in dry season is less than the demand
D. the rate of flow in the stream is equal to the demand

10. The method of plane tabling commonly used for establishing the instrument station is a method of

B. intersection
C. resection
D. traversing

11. A fixed beam of unifrom section is carrying a point load at its mid-span. If the moment of inertia of the middle half length is now reduced to half its previous value, then the fixed end moments will

A. Increase
B. decrease
C. remain constant
D. change their directions

12. The moisture content of a clayey soil is gradually decreased from a large value. What will be the correct sequence of the occurrence of the following limits ?1. Shrinkage limit2. Plastic limit3. Liquid limitSelect the correct answer from the codes given below :

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

13. For the movement of vehicles at an intersection of two roads without any interference, which type of grade separation is generally preferred ?

A. Delta
B. Diamond
C. Trumpet
D. Cloverleaf

14. Which one of the following stresses is independent of yield stress as a permissible stress for steel members ?

A. Axial tensile stress
B. Maximum shear stress
C. Bearing stress
D. Stress in slab base

15. Permissible limit of cant deficiency for Broad Gauge (B.G.) is

A. 50 mm
B. 60 mm
C. 75 mm
D. 88 mm

16. If the line of sight between two stations A and B, on sea, and 80 km apart, makes tangent at point A, then the minimum elevation of the signal required at B (considering the coefficient of refraction "m" = 0.08 and the mean radius of earth as 6400 km) will be

A. 42 m
B. 210 m
C. 420 m
D. 840 m

17. A simply supported beam of uniform cross-section is subjected to a maximum bending moment of 2.25 t.m. If it has rectangular cross-section with width 15 cm and depth 30 cm, then the maximum bending stress induced in the beam will be

A. 50 kg/cm2
B. 100 kg/cm2
C. 150 kg/cm2
D. 225 kg/cm2

18. Consider the following statements regarding underreamed piles :1. They are used in expansive soils.2. They are of perkcast reinforced concrete.3. The ratio of bulb to shaft diameters is usually 2 to 3.4. Minimum spacing between the piles should not be less than 1.5 times the bulb diameter. of these statements :

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

19. What is efflorescence ?

A. Formation of white patches on the brick surface due to insoluble salts in the brick clay
B. Swelling of brick due to presence of carbonaceous matter and gas
C. Deformation of brick due to exposure to rain
D. Impurities in the brick clay which show after burning

20. Consider the following statements regarding a beam of uniform cross-section simply supported at its ends and carrying a concentrated load at one of its third points :1. Its deflection under the load will be maximum.2. The bending moment under the load will be maximum.3. The deflection at the mid-point of the span will be maximum.4. The slope at the nearer support will be maximum.Of these statements :

A. 1 and 3 are correct
B. 2 and 4 are correct
C. 1 and 2 are correct
D. 3 and 4 are correct

21. What is the recommended grade of tar for grouting purpose ?

A. RT - 1
B. RT - 2
C. RT - 3
D. RT - 5

22. Which of the following statements is/are true in relation to the term 'detention period' in a settling tank?1. It may be determined by introducing a dye in the inlet and timing its appearance at the outlet.2. Greater the detention period, greater the efficiency of removal of settleable matter.3. It is the time taken for any unit of water to pass through the setting basin.4. It is usually more than the flowthrough period.Select the correct answer using the codes given below :

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

23. If a soil sample of weight 0.18 kg having a volume of 10-4 m3 and dry unit wt. of 1600 kg/m3 is mixed with 0.02 kg of water then the water content in the sample will be

A. 30%
B. 25%
C. 20%
D. 15%

24. With 'n' variables and 'm' fundamental dimensions in a system, which one of the following statements relating to the application of the Buckingham's Pi Theorem is incorrect ?

A. With experience, pi terms can be written simply by inspection of variables in a flow system
B. Buckingham's pi theorem is not directly applicable in compressible flow problem
C. Buckingham's pi theorem yields dimensionless pi terms given by the difference between the number of variables and the number of fundamental dimensions
D. Buckingham's pi theorem reduces the number of variables by the number of fundamental dimensions involved.

25. Two sources generate noise levels of 90 dB and 94 dB respectively. The cumulative effect of these two noise levels on the human ear is

A. 184 dB
B. 95.5 dB
C. 94 dB
D. 92 dB

26. A cohesionless soil having an angle of shearing resistance of φ, is standing at a slope angle of i. The factor of safety of the slope is tan i

A.
B. tan i - tan φ
C.
D. tan φ - tan i

27. Sewage sickness occurs when

A. Sewage contains pathogenic organisms
B. sewage enters the water supply system
C. sewers get clogged due to accumulation of solids
D. voids of soil get closed due to continuous application of sewage on a piece of land

28. A steel cable of 2 cm diameter is used to lift a load of 500π kg. Given that, E = 2 x 106 kg/cm2 and the length of the cable is 10 m, the elongation of the cable due to the load will be

A. 0.5 cm
B. 0.25
C. 1 cm
D. 1/π cm

29. Consider the following statements regarding tensile test diagrams for carbon steel with varying carbon contents :As the carbon content increases1. the ultimate strength of steel decreases 2. the elongation before fracture increases3. the ductility of the metal decreases 4. the ultimate strength increases.Of these statements :

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

30. Negative skin friction on a pile under vertical compressive load acts

A. downwards and increases the load carrying capacity of the pile
B. downwards and reduces the load carrying capacity of the pile
C. upwards and increases the load carrying capacity of the pile
D. downwards and maintains the same load carrying capacity of the pile

31. The defect which develops due to uncontrolled and non-uniform loss of moisture from wood is known as which one of the following ?

A. Kont
B. Shake
C. Warping
D. Cross grain

32. Consider the following statements in respect of the critical depth of flow in a prismatical rectangular channel:1. For known specific emergy, discharge is minimum.2. For known discharge, the specific energy is minimum.Which of the statements given above is/are correct ?

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

33. On the basis of the data given in the following figures, the bending moment under the load would work out to

A. 2 kN.m
B. 4 kN.m
C. 6 kN.m
D. 12 kN.m

34. What is the innermost portion of approach zone which is the most critical portion from obstruction viewpoint, called ?

A. Outer horizontal surface
B. Conical surface
C. Inner horizontal surface
D. Clear zone

35. A circular plate 100 mm diameter is welded to another plate by means of 6 mm fillet weld. If the permissible shearing stress in the weld equals 10 kg/mm2, then the greatest twisting moment that can be resisted by the weld will be

A. 424 π kg.m
B. 300 π kg.m
C. 212 π kg.m
D. 60 π kg.m

36. A fixed beam is subjected to ment M0 as shown in the figure. The fixed end moments will be :

A. zero
B. M0
C. M0/2
D. 2M0

37. Consider the following steps :1. Driving sheet piles surrounding a vibration-receiving structure.2. Digging a trench around a source of vibration.3. Placing rubber mountings between a machine causing vibration and its base. Active isolation of vibration can be achieved by

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

38. Two reservoirs at different surface elevations are connected by a set of two pipes A and B of same diameter and length in parallel. If the friction factor of A is 4 times that of the pipe B, what is the ratio of the discharge in A to that in B ?

A. 0.25
B. 4.0
C. 2.0
D. 0.5

39. Which of the following should be employed to provide lateral support to the beams ?1. Bracing of compression flanges.2. Shear connectors.3. Bracing of tension flanges4. Embedding compression flanges into R.C.C. slab.Select the correct answer using the codes given below :

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

6. What is the ratio of maximum shear stress to average shear stress for a circular section ?

A. 2
B.
C.
D.

7. If a circular shaft is subjected to a torque T and a bending moment 'M' the ratio of the maximum shear stress to the maximum bending stress is given by :

A. 2M/T
B. T/2M
C. 2T/M
D. M/2T

8. Which one of the following statements is not correct ?

A. Models are always smaller than the prototypes.
B. Dynamic similarity between a model and a prototype can be verified by equating Reynold's number in a viscous flow.
C. Mach number achieves significance when the velocity of fluid approaches or exceeds the sonic velocity.
D. Distorted models are always exaggerated on a vertical scale.

9. The construction of impounding reservoir is required when

A. average annual flow in the stream is lower than average demand
B. the rate of flow in the stream, in dry season in more than the demand
C. the rate of flow in the stream, in dry season is less than the demand
D. the rate of flow in the stream is equal to the demand

10. The method of plane tabling commonly used for establishing the instrument station is a method of

B. intersection
C. resection
D. traversing