Concrete Technology MCQ – Aggregate MCQ

61. The strength of concrete mainly depends on

1. quality of course aggregates
2. water cement ratio
3. fineness of cement
4. quality of fine aggregates

62. The breaking up of cohesion in a mass of concrete is called

1. segregation
2. creep
3. workability
4. bleeding

63. Plain cement concrete is strong in taking

1. shear stress
2. tensile stress
3. compressive stress
4. all of three mentioned here

64. In fresh concrete, if sugar is added and concrete is mixed. The observed effect is

1. no effect
2. delay in setting time of cement concrete
3. improvement in concrete strength
4. acceleration in setting time of cement concrete

65. Rebound hammer test is useful for determination of _________ of hardened concrete.

1. permeability
2. compressive strength
3. tensile strength
4. shear strength

66. The ratio of tensile strength to compressive strength of concrete is about

1. 1/10
2. 1/2
3. 1/20
4. 1/5

67. The maximum bulking of sand is likely to occur at a moisture content of

1. 5%
2. 8%
3. 11%
4. 14%

68. Organic matter in water for making concrete should not be more than

1. 1,000 ppm
2. 3,000 ppm
3. 10,000 ppm
4. 15,000 ppm

69. Shrinkage of concrete depends upon the

1. relative humidity of the atmosphere
2. passage of time
3. applied stress

Which of these statements is/are correct?

1. ii and iii
2. i and ii
3. i, ii and iii
4. i alone

70. The split tensile strength of M15 grade concrete when expressed as a percentage of its compressive strength is

1. 15 to 20%
2. 10 to 15%
3. 25 to 30%
4. 20 to 25%