Civil engineer objective questions – Design of Concrete Structure (Section-3)

51. If the height is equal to length of RCC wall, the percentage increase in strength is

a) 0

b) 10

c) 20

d) 30

52. 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

53. The average permissible stress in bond for plain bars in tension is

a) Increase by 10% for bars in compression

b) Increase by 25% for bars in compression

c) Decrease by  10% for bars in compression

d) Decrease by 25% for bars in compression

54. Maximum distance between expansion joints in structures as per IS: 456 – 1978 is

a) 20m

b) 20m

c) 45m

d) 60m

55. A higher modular ratio shows

a) Higher compressive strength of concrete

b) Lower compressive strength of concrete

c) Higher tensile strength of steel

d) Lower tensile strength of steel

56. Ratio of permissible stress in direct compression and bending compression is

a) Less Than 1

b) Between 1 and 1.5

c) Between 1.5 and 2.0

d) Greater than 2

57. In working stress design, permissible bond stress in the case of deformed bars is more than that in plain bars by

a) 10%

b) 20%

c) 30%

d) 40%

58. Half of the main steel in a simply supported slab is bent up near the support at a distance of x from the centre of slab bearing where x is equal to

a) 1/3

b) 1/5

c) 1/7

d) 1/10

59. If the size of panel in a flat slab is 6m * 6m, then as per Indian standard code, the widths of column strip and middle strip are

a) 3.0 and 1.5 m

b) 1.5 m and 3.0 m

c) 1.5 m and 3.0 m

d) 1.5 m and 1.5 m

60. The permissible diagonal tensile stress in reinforced brick work is

a) About 0.1 N/mm2

b) Zero

c) 0.3 N/mm2 to 0.7 N/mm2

d) About 1.0 N/mm2

61. When shear stress exceeds the permissible limit in a slab, then it is reduced by

a) Increasing the depth

b) Providing shear reinforcement

c) Using high strength steel

d) Using thinner bars but more in number

62. 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

63. The limits of percentage p of the longitudinal reinforcement in a column is given by

a) 0.15% to 2%

b) 0.8% to 4%

c) 0.8% to 6%

d) 0.8% to 8%

64. 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

65. Maximum percentage reinforcement in case of slabs is limited to

a) 2

b) 4

c) 6

d) 8

66. The diameter of ties in a column should be

a) More than or equal to one fourth of diameter of main bar

b) More than or equal to 5 mm

c) More than 5 mm but less than one-fourth of diameter of main bar

d) More than 5 mm and also more than one-fourth of diameter of main bar

67. For the design of retaining walls, the minimum factor of safety against overturning is taken as

a) 1.5

b) 2.0

c) 2.5

d) 3.0

68. The load carrying capacity of a helically reinforced column as compared to that of a tired column is about

a) 5% less

b) 10% less

c) 5% more

d) 10% more

69. Due to circumferential action of the spiral in a spirally reinforced column

a) Capacity of column is decreased

b) Ductility of column reduces

c) Capacity of column is decreased but ductility of column increases

d) Both the capacity of column and ductility of column increase

70. The temperature reinforcement in the vertical of a T-shaped R.C. retaining wall is

a) Not needed

b) Provided equally on inner and front faces

c) Provided more on inner face than on front face

d) Provided more on front face than on inner face

71. Modulus of elasticity of steel as per IS: 456-1978 shall be taken as

a) 20 kN/cm2

b) 200 kN/cm2

c) 200 kN/mm2

d) 2*l06N/cm2

72. For a reinforced concrete section, the shape of shear stress diagram is

a) Wholly parabolic

b) Wholly rectangular

c) Parabolic above neutral axis and rectangular below neutral axis

d) Rectangular above neutral axis and parabolic below neutral axis

73. The main reinforcement in the heel of T-shaped R.C. retaining wall is provided on

a) Top face perpendicular to wall

b) Bottom face perpendicular to wall

c) Both top and bottom faces perpendicular to wall

d) None of the above

74. 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

75. In a counterfort retaining wall, the main reinforcement in the stem at mid span is provided on

a) Front face only

b) Inner front face and inner face

d) None of the above