Concrete Technology and Design 1000+ MCQ with answer for UPSC IES

1. For walls, columns and vertical faces of all structural members, the form work is generally removed after
A. 24 to 48 hours
B. 3 days
C. 7 days
D. 14 days
Answer : A

2. For a good concrete
A. Aggregates should be hard and durable
B. Water should be free from organic materials
C. Cement should be sufficient to produce the required strength
D. All the above
Answer : D

3. If the slump of a concrete mix is 60 mm, its workability is
A. Very low
B. Low
C. Medium
D. High
Answer : C

4. The compressive strength of 100 mm cube as compared to 150 mm cube is always
A. Less
B. More
C. Equal
D. None of the above
Answer : B

5. Approximate value of shrinkage strain in concrete, is
A. 0.003
B. 0.0003
C. 0.00003
D. 0.03
Answer : B

6. The main reason for providing number of reinforcing bars at a support in a simply supported beam is to resist in that zone
A. Compressive stress
B. Shear stress
C. Bond stress
D. Tensile stress
Answer : C

7. The load factors for live load and dead load are taken respectively as
A. 1.5 and 2.2
B. 2.2 and 1.5
C. 1.5 and 1.5
D. 2.2 and 2.2
Answer : B

8. How long will it take for the concrete to achieve 100% of its strength?
A. 7 days
B. 14 days
C. 21 days
D. 28 days
Answer : D

9. After casting, an ordinary cement concrete on drying
A. Expands
B. Mix
C. Shrinks
D. None of these
Answer : C

10. Minimum thickness of load bearing RCC wall should be
A. 50 mm
B. 100 mm
C. 150 mm
D. 200 mm
Answer : B

11. Permissible compressive strength of M 150 concrete grade is
A. 100 kg/cm2
B. 150 kg/cm2
C. 200 kg/cm2
D. 250 kg/cm2
Answer : C

12. The most commonly used admixture which prolongs the setting and hardening time is
A. Gypsum
B. Calcium chloride
C. Sodium silicate
D. All of the above
Answer : A

13. Percentage of pozzolanic material containing clay upto 80% used for the manufacture of pozzolana cement, is
A. 30 %
B. 40 %
C. 50 %
D. 60 %
Answer : A

14. While designing the pile as a column, the end conditions are nearly
A. Both ends hinged
B. Both ends fixed
C. One end fixed and other end hinged
D. One end fixed and other end free
Answer : C

15. According to Whitney's theory, ultimate strain of concrete is assumed to be
A. 0.03 %
B. 0.1 %
C. 0.3 %
D. 3 %
Answer : C

16. Cement used for normal concrete construction, is obtained by burning a mixture of
A. Siliceous and argillaceous materials
B. Argillaceous and calcareous materials
C. Siliceous and calcareous materials
D. Siliceous, argillaceous and calcareous materials
Answer : D

17. For road pavements, the cement generally used, is
A. Ordinary Portland cement
B. Rapid hardening cement
C. Low heat cement
D. Blast furnace slag cement
Answer : B

18. Modulus of rupture of concrete is a measure of
A. Flexural tensile strength
B. Direct tensile strength
C. Compressive strength
D. Split tensile strength
Answer : A

19. The dimensions of a 35 litre forma for measuring aggregates by volume, are:
A. Length 30 cm, breadth 25 cm, height 30 cm
B. Length 39 cm, breadth 25 cm, height 32 cm
C. Length 27 cm, breadth 27 cm, height 48 cm
D. Length 220 cm, breadth 25 cm, height 40 cm
Answer : C

20. Pick up the correct statement from the following:
A. Sand stones may be divided into calcareous, siliceous and ferruginous sand stones
B. Concrete using sand stones, cracks due to excessive shrinkage
C. Broken bricks produce a concrete having good fire resisting qualities
D. All the above
Answer : D

21. An aggregate which passes through 25 mm I.S. sieve and is retained on 20 mm sieve, is said to be flaky if its least dimension is less than
A. 22.5 mm
B. 18.5 mm
C. 16.5 mm
D. 13.5 mm
Answer : D

22. Log Angles machine is used to test the aggregate for
A. Crushing strength
B. Impact value
C. Abrasion resistance
D. Water absorption
Answer : C

23. The maximum amount of dust which may be permitted in aggregates is
A. 5% of the total aggregates for low workability with a coarse grading
B. 10% of the total aggregates for low workability with a fine grading
C. 20% of the total aggregates for a mix having high workability with fine grading
D. All the above
Answer : D

24. Pick up the correct statement from the following:
A. High percentage of C₃S and low percentage of C₂S cause rapid hardening
B. High percentage of C₃S and low percentage of C₂S make the cement less resistive to chemical attack
C. Low percentage of C₃S and high percentage of C₂S contribute to slow hardening
D. All the above
Answer : D

25. Pick up the incorrect statement from the following:
A. Concrete for which preliminary tests are conducted, is called controlled concrete
B. Bulking of sand depends upon the fineness of grains
C. Concrete mix 1 : 6 : 12, is used for mass concrete in piers
D. All the above
Answer : D

26. 'Ware house pack' of cement means
A. Full capacity of the ware house
B. Pressure exertion of the bags of upper layers
C. Pressure compaction of the bags on lower layers
D. Packing the ware house
Answer : C

27. Proper proportioning of concrete, ensures
A. Desired strength and workability
B. Desired durability
C. Water tightness of the structure
D. All the above
Answer : D

28. The factor which affects workability, is
A. Water content and its temperature
B. Shape and size of the aggregates
C. Air entraining agents
D. All the above
Answer : D

29. For a concrete mix 1:3:6 and water cement ratio 0.6 both by weight, the quantity of water required per bag, is
A. 10 kg
B. 12 kg
C. 14 kg
D. 16 kg
Answer : C

30. The effect of adding calcium chloride in concrete is (i) To increase shrinkage (ii) To decrease shrinkage (iii) To increase setting time (iv) To decrease setting time The correct answer is
A. (i) and (iii)
B. (i) and (iv)
C. (ii) and (iii)
D. (ii) and (iv)
Answer : B

31. Which of the following R.C. retaining walls is suitable for heights beyond 6 m?
A. L-shaped wall
B. T-shaped wall
C. Counterfort type
D. All of the above
Answer : C

32. The minimum cover to the ties or spirals should not be less than
A. 15 mm
B. 20 mm
C. 25 mm
D. 50 mm
Answer : C

33. Le-Chatelier's apparatus is used for testing
A. Soundness of cement
B. Hardness of cement
C. Strength of cement
D. Durability of cement
Answer : A

34. According to ISI recommendations, the maximum depth of stress block for balanced section of a beam of effective depth d is
A. 0.43 d
B. 0.55 d
C. 0.68 d
D. 0.85 d
Answer : A

35. High temperature
A. Increases the strength of concrete
B. Decreases the strength of concrete
C. Has no effect on the strength of concrete
D. None of these
Answer : B

36. Pick up the incorrect statement from the following. While performing preliminary test on concrete
A. Proportions of the material and water should be the same as to be used at the work site
B. Cement should be mixed by hand in order to maintain uniformity
C. Concrete mix should be stored in air-tight containers
D. Concrete ingredients should be kept at a temperature of 37° ± 2°C
Answer : D

37. Pick up the correct statement from the following:
A. The free water is the amount of water added while mixing and the amount of water held on the surface of the aggregates prior to mixing
B. The total water is the free water and the amount actually absorbed by the aggregates
C. Neither (a) nor (b)
D. Both (a) and (b)
Answer : D

38. An ideal ware house, is provided
A. Water proof masonry walls
B. Water proof roof
C. Few windows which remain generally closed
D. All the above
Answer : D

39. Workability improved by adding
A. Fly ash
B. Hydrated lime
C. Calcium chloride
D. All the above
Answer : D

40. A construction joint is provided where
A. Bending moment is small
B. Shear force is small
C. The member is supported by other member
D. All the above
Answer : D

41. Setting time of cement increases by adding
A. Gypsum
B. Hydrogen peroxide
C. Calcium chloride
D. Sodium oxide
Answer : A

42. Construction joints are generally provided in concrete
A. Roads
B. Retaining walls
C. Lining of canals
D. All the above
Answer : D

43. If the effective working time is 7 hours and per batch time of concrete is 3 minutes, the output of a concrete mixer of 150 litre capacity, is
A. 15,900 litres
B. 16,900 litres
C. 17,900 litres
D. 18,900 litres
Answer : D

44. The process of proper and accurate measurement of concrete ingredients for uniformity of proportion, is known
A. Grading
B. Curing
C. Mixing
D. Batching
Answer : D

45. Pick up the correct statement from the following:
A. According to the petrological characteristics, concrete aggregates are classified as heavy weight, normal weight and light weight
B. According to the shape of the particles, concrete aggregates are classified as rounded irregular, angular and flaky
C. According to the surface texture of the particles, the concrete aggregates are classified as glassy, smooth, granular, rough, crystalline, honey combed and porous
D. All the above
Answer : D

46. Workability of concrete for a given water content is good if the aggregates, are
A. Rounded aggregate
B. Irregular aggregate
C. Angular aggregate
D. Flaky aggregates
Answer : A

47. Critical section for shear in case of flat slabs is at a distance of
A. Effective depth of slab from periphery of column/drop panel
B. d/2 from periphery of column/capital/ drop panel
C. At the drop panel of slab
D. At the periphery of column
Answer : B

48. The size of fine aggregates does not exceed
A. 2.75 mm
B. 3.00 mm
C. 3.75 mm
D. 4.75 mm
Answer : D

49. In a counterfort retaining wall, the main reinforcement in the stem at mid span is provided on
A. Front face only
B. Inner face only
C. Both front face and inner face
D. None of the above
Answer : A

50. The surface where two successive placements of concrete meet, is known as
A. Contraction joint
B. Expansion joint
C. Construction joint
D. Both (a) and (b)
Answer : C