31. Which of the following test is used to estimate soundness of ordinary Portland Cement?
- Mortar bar test
- Abram’s slump cone test
- Flow table test
- Le Chatelier’s test
32. The setting time of cement can be increased by the addition of
- Calcium chloride
- Hydrogen peroxide
33. Fineness for OPC should not be less than in (mm3/g × 102)
34. IS code for Portland pozzolona cement is
- IS 269
- IS 1489
- IS 455
- IS 3466
35. Amount of water required for soundness test is (in percentage)
(where P is percentage of water corresponding to standard consistency)
- 0.85 P
- 0.78 P
- 0.75 P
- 0.87 P
36. As per IS 10262, OPC is divided into how many grades?
37. Which compound has maximum percentage proportion in cement?
38. The volume of 50 kg cement bag will be
- 1.25 cmt.
- 0.034 cmt.
- 0.283 cmt.
- 0.050 cmt.
39. What is the maximum permissible additives in cement for construction as per IS code?
40. Initial setting time of cement shall not be less than
- 60 min.
- 30 min.
- 75 min.
- 45 min.
41. Which test is carried out to know about free limit in cement?
- Soundness test
- Consistency test
- Setting time test
- Fineness test
42. White cement is white in colour due to
- use of limestone and china clay free from metal oxides
- its modified manufacturing process
- specific chemical treatment given to ordinary cement
- none of these
43. The total percentage of dicalcium silicate and tricalcium silicate in all types of Portland cement is around
44. The main advantage of adding pozzolanas in cement is
- longer life
- reduced cost and permeability of concrete
- slower setting time
- faster setting time
45. In Vicat’s apparatus, the cross-sectional area of needle used is ______, and time to penetrate _______ is used to measure initial setting time of cement.
- 10 mm2, 20-25 min
- 1 mm2, 33-35 min
- 5 mm2, 5 min
- 1 mm2, 0.5 min
46. Soundness test is carried out on cement to determine
- sound penetration capacity of cement
- the presence of sound material in cement
- the presence of uncombined lime in cement
- none of these
47. The fineness of cement is expressed as
48. In fineness test of Rapid Hardening Portland Cement (RHPC) the residue on IS sieve No. 9 should not be more than
49. In dry process of cement manufacturing rotary klin in charged at a temperature
- Less than 1200°C
- Between 1300°C and 1450°C
- Between 1500°C and 1800°C
- More than 1800°C
50. What percentage of bound water by weight of cement is required for chemical reaction with Portland cement compounds?
51. The fineness of cement can be found out by sieve analysis using IS sieve number
52. Based on the heat released upon hydration, arrange the following four compounds of the cement (1. C3S, 2. C2S, 3. C3A 4. C4AF) in descending order.
- 3, 1, 4, 2
- 1, 2, 3, 4
- 3, 4, 1, 2
- 3, 4, 2, 1
53. The minimum compressive strength (MPa) of 53 grade Ordinary Portland Cement after 72 hours should not be less than
54. Blast furnace slag has approximately
- 45% calcium oxide and about 35% silica
- 50% alumina and 20% calcium oxide
- 25 % magnesia and 15% silica
- 25% calcium sulphate and 15% alumina
55. Which of the following is the first one to participate in hydration reaction of cement paste?
- Dicalcium silicate
- Tricalcium silicate
- Tricalcium aluminate
- Tetracalcium aluminoferrite
56. Green colour of cement is caused by
- Magnesium oxide
- Iron oxide
- Carbon pigments
- Chromium dioxide
57. Fineness of cement is measured in the units of
58. Refractory cement is rich in
59. Deficiency of which of the following oxide causes reduction in setting time of cement
60. The minimum water-cement ratio for a workable concrete is