1000+ Concrete Technology and Design Multiple Choice Question Answer [Solved]

1. Increase in the moisture content in concrete
A. Reduces the strength
B. Increases the strength
C. Does not change the strength
D. All of the above
Answer : A

2. To ensure constant moisture content in aggregates
A. Area of each aggregate pile should be large
B. Height of each aggregate pile should not exceed 1.50 m
C. Aggregate pile should be left for 24 hours before aggregates are used
D. All the above
Answer : D

3. Pick up the correct statement from the following:
A. Water cement paste hardens due to hydration
B. During hardening cement binds the aggregates together
C. Cement provides strength, durability and water tightness to the concrete
D. All the above
Answer : D

4. The property of the ingredients to separate from each other while placing the concrete is called
A. Segregation
B. Compaction
C. Shrinkage
D. Bulking
Answer : A

5. The diameter of the Vicat plunger is 10 mm and its length varies from
A. 20 mm to 30 mm
B. 30 mm to 40 mm
C. 40 mm to 50 mm
D. 50 mm to 60 mm
Answer : C

6. An excess of flaky particles in concrete aggregates
A. Decreases the workability
B. Increases the quantity of water and sand
C. More than 15% are not desirable
D. All the above
Answer : D

7. A concrete having a slump of 6.5 cm, is said to be
A. Dry
B. Earth moist
C. Semi-plastic
D. Plastic
Answer : D

8. Pick up the incorrect statement from the following:
A. Space between the exterior walls of a warehouse and bag piles should be 30 cm
B. Cement bags should preferably be piled on wooden planks
C. Width and height of the pile should not exceed 3 m and 2.70 m respectively
D. None of these
Answer : D

9. An aggregate is said to be flaky if its least dimension is less than
A. 1/5th of mean dimension
B. 2/5th of mean dimension
C. 3/5th of mean dimension
D. 4/5th of mean dimension
Answer : C

10. In counterfort retaining walls, the main reinforcement in the stem at support is
A. Not provided
B. Provided only on inner face
C. Provided only on front face
D. Provided both on inner and front faces
Answer : B

11. The factor of safety for
A. Steel and concrete are same
B. Steel is lower than that for concrete
C. Steel is higher than that for concrete
D. None of the above
Answer : B

12. Transport of concrete by pumps, is done for a distance of
A. 100 m
B. 200 m
C. 300 m
D. 400 m
Answer : D

13. 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

14. Joints in concrete structures, are provided
A. To reduce the tensile stresses likely to be developed due to evaporation of water
B. To minimise the change in the dimensions of the slab
C. To minimise the necessary cracking
D. All the above
Answer : D

15. The compaction of concrete, improves
A. Density
B. Strength
C. Durability
D. All the above
Answer : D

16. Pick up the correct statement from the following:
A. Continuous grading is not necessary for obtaining a minimum of air voids
B. The omission of a certain size of aggregate is shown by a straight horizontal line on the grading curve
C. The omission of a certain size of aggregate in concrete increases the workability but also increases the liability to segregation
D. All the above
Answer : D

17. For quality control of Portland cement, the test essentially done is
A. Setting time
B. Tensile strength
C. Consistency
D. All the above
Answer : D

18. According to IS: 4561978, the column or the strut is the member whose effective length is greater than
A. The least lateral dimension
B. 2 times the least lateral dimension
C. 3 times the least lateral dimension
D. 4 times the least lateral dimension
Answer : C

19. Addition of pozzolana to cement
A. Decreases workability
B. Increases strength
C. Increases heat of hydration
D. None of these
Answer : D

20. For concreting tunnel linings, transportation of concrete is done by
A. Pans
B. Wheel borrows
C. Containers
D. Pumps
Answer : D

21. According to IS: 4561978, the maximum reinforcement in a column is
A. 2 %
B. 4 %
C. 6 %
D. 8 %
Answer : C

22. In a spherical dome the hoop stress due to a concentrated load at crown is
A. Compressive everywhere
B. Tensile everywhere
C. Partly compressive and partly tensile
D. Zero
Answer : B

23. Pick up the correct statement from the following:
A. Segregation is necessary for a workable concrete
B. Consistency does not affect the workability of concrete
C. If the concrete mix is dry, the slump is maximum
D. None of these
Answer : D

24. If 50 kg of fine aggregates and 100 kg of coarse aggregates are mixed in a concrete whose water cement ratio is 0.6, the weight of water required for harsh mix, is
A. 8 kg
B. 10 kg
C. 12 kg
D. 14 kg
Answer : C

25. If the various concrete ingredients i.e. cement, sand and aggregates are in the ratio of 1:3:6, the grade of concrete, is
A. M 100
B. M 150
C. M 200
D. M 250
Answer : A

26. In reinforced concrete footing on soil, the minimum thickness at edge should not be less than
A. 100 mm
B. 150 mm
C. 200 mm
D. 250 mm
Answer : B

27. Under normal conditions using an ordinary cement, the period of removal of the form work, is:
A. 7 days for beam soffits
B. 14 days for bottom slabs of spans 4.6 m and more
C. 21 days for bottom beams over 6 m spans
D. All the above
Answer : D

28. The internal dimensions of a ware house are 15 m × 5.6 m, and the maximum height of piles is 2.70 m, the maximum number of bags to be stored in two piles, are
A. 1500 bags
B. 2000 bags
C. 2500 bags
D. 3000 bags
Answer : D

29. The centroid of compressive force, from the extreme compression fiber, in limit state design lies at a distance of (Where x_u is the depth of neutral axis at the limit state of collapse)
A. 0.367 x_u
B. 0.416 x_u
C. 0.446 x_u
D. 0.573 x_u
Answer : B

30. The recommended value of modular ratio for reinforced brick work is
A. 18
B. 30
C. 40
D. 58
Answer : C

31. Workability of concrete is measured by
A. Vicat apparatus test
B. Slump test
C. Minimum void method
D. Talbot Richard test
Answer : B

32. An aggregate is known as cyclopean aggregate if its size is more than
A. 4.75 mm
B. 30 mm
C. 60 mm
D. 75 mm
Answer : D

33. Grading of sand causes great variation in
A. Workability of concrete
B. Strength of concrete
C. Durability of concrete
D. All the above
Answer : D

34. 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

35. 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

36. According to Whitney's theory, depth of stress block for a balanced section of a concrete beam is limited to
A. 0.43 d
B. 0.537 d
C. 0.68 d
D. 0.85 d Where d is effective depth of beam
Answer : B

37. A continuous beam is deemed to be a deep beam when the ratio of effective span to overall depth (1/D) is less than
A. 1.5
B. 2.0
C. 2.5
D. 3.0
Answer : C

38. If fineness modulus of sand is 2.5, it is graded as
A. Very fine sand
B. Fine sand
C. Medium sand
D. Coarse sand
Answer : B

39. Pick up the correct proportions of chemical ingredients of cement
A. Lime : Silica : Alumina : Iron oxide : 63 : 22 : 6 : 3
B. Silica : Lime : Alumina : Iron oxide : 63 : 22 : 6 : 3
C. Alumina : Silica : Lime : Iron oxide : 63 : 22 : 6 : 3
D. Iron oxide : Alumina : Silica : Lime : 63 : 22 : 6 : 3
Answer : A

40. Slump test of concrete is a measure of its
A. Consistency
B. Compressive strength
C. Tensile strength
D. Impact value
Answer : A

41. The high strength of rapid hardening cement at early stage, is due to its
A. Finer grinding
B. Burning at high temperature
C. Increased lime cement
D. Higher content of tricalcium
Answer : C

42. The grade of concrete M 150 means that compressive strength of a 15 cm cube after 28 days, is
A. 100 kg/cm2
B. 150 kg/cm2
C. 200 kg/cm2
D. 250 kg/cm2
Answer : B

43. In the method of voids for determination of the quantity of cement paste, it is assumed that
A. Voids in coarse aggregates are filled by fine aggregates
B. Voids in fine aggregates are filled by the cement paste
C. Volume of fine aggregates is equal to total voids in coarse aggregates plus 10% extra
D. All the above
Answer : D

44. Pick up the correct statement from the following:
A. A highly absorptive aggregate reduces the workability of concrete considerably
B. The specific gravity of aggregate is important for the determination of the moisture content
C. The absorption and porosity of an aggregate influence the property of the concrete
D. All the above
Answer : D

45. The slab is designed as one way if the ratio of long span to short span is
A. Less than 1
B. Between 1 and 1.5
C. Between 1.5 and 2
D. Greater than 2
Answer : D

46. The strength and quality of concrete, depend upon:
A. Grading of aggregates
B. Surface area of aggregates
C. Shape of aggregates
D. All the above
Answer : D

47. The process of hardening the concrete by keeping its surface moist is known
A. Placing
B. Wetting
C. Curing
D. Compacting
Answer : C

48. According to IS : 382-1963, a good aggregate should be
A. Chemically inert
B. Sufficiently strong
C. Hard and durable
D. All the above
Answer : D

49. The final operation of finishing floors, is known as
A. Screeding
B. Floating
C. Trowelling
D. Finishing
Answer : C

50. Permissible compressive strength of M 300 concrete grade is
A. 100 kg/cm²
B. 150 kg/cm²
C. 200 kg/cm²
D. 300 kg/cm²
Answer : D