Quiznetik

Design of Steel Structures | Set 4

1. The effective length of a compression member of length L held in position at both ends but not restrained in direction, is

Correct : A. L

2. The live load for a sloping roof with slope 15°, where access is not provided to roof, is taken as

Correct : A. 0.65 kN/m²

3. Pick up the correct statement from the following:

Correct : A. Dead load includes self-weight of the structure and super-imposed loads permanently attached to the structure

4. If N is the number of rivets in the joint, the strength of a riveted joint against shearing of rivets, is given by

Correct : A. Ps = N d2 × Ps

5. The sway bracing is designed to transfer

Correct : D. 50% of the top panel wind load to bottom bracing

6. Column footing is provided

Correct : D. All the above

7. Rolled steel beams are designated by Indian Standard series and its

Correct : B. Depth of section and weight per metre

8. When plates are exposed to weather, tacking rivets are provided at a pitch in line not exceeding (where t is the thickness of the outside plate).

Correct : B. 16 t

9. For a compression member with double angle section, which of the following section will give larger value of minimum radius of gyration?

Correct : B. Unequal legged angles with long legs back to back

10. Pick up the correct statement from the following:

Correct : A. The minimum pitch should not be less than 2.5 times the gross diameter of the river

11. Pitch of tacking rivets, when double angles connected back to back and acting as tension members should not be more than

Correct : C. 1000 mm

12. For a steel grillage footing to support two unequal column loads

Correct : D. All the above

13. In a tension member if one or more than one rivet holes are off the line, the failure of the member depends upon:

Correct : D. All the above

14. The effective length of a compression member of length L, held in position and restrained in direction at both ends, is

Correct : B. 0.67 L

15. By providing sufficient edge distance, which of the following failures of riveted joint can be avoided?

Correct : C. Shear failure of the plate

16. The maximum tensile and compressive bending stress in extreme fibres of rolled I-sections and channels on the effective section, is

Correct : C. 1650 kg/cm2

17. When the ratio of the moment M to axial load P is greater than L/6, the resultant of the compressive bearing pressure which acts at a distance Y from one side, is given by

Correct : B. y = (L/2) - (P/M)

18. The safe working pressure for a spherical vessel 1.5 m diameter and having 1.5 cm thick wall not to exceed tensile stress 50kg/cm2, is

Correct : C. 20 kg/cm2

19. Battening is preferable when the (i) Column carries axial load only (ii) Space between the two main components is not very large (iii) Column is eccentrically loaded The correct answer is

Correct : C. (i) and (ii)

20. For a steel member of slenderness ratio 350, the allowable stress is 76 kg/cm2 if it is

Correct : D. All the above

21. Bearing stiffener in a plate girder is used to

Correct : B. Prevent buckling of web

22. The central deflection of a simply supported steel beam of length L with a concentrated load W at the centre, is

Correct : C. WL3/48EI

23. If d is the distance between the flange angles,

Correct : D. All the above

24. In case horizontal stiffeners are not used, the distance between vertical legs of flange angles at the top and bottom of a plate girder, is known as

Correct : B. Clear depth

25. Pick up the correct statement from the following:

Correct : D. Continuous fillers are supported by main steelbeams

26. The diameter of base of conical flare of a steel stack is ( d is the diameter of the cylindrical part)

Correct : C. More than d

27. The effective length of a compression member of length L held in position and restrained in direction at one end and effectively restrained in direction but not held in position at the other end, is

Correct : A. L

28. Working shear stress on the gross area of a rivet as recommended by Indian Standards, is

Correct : B. 1025 kg/cm2

29. The critical load for a column of length I hinged at both ends and having flexural rigidity El, is given by

Correct : A. Pc = ²EI/l²

30. Length of an outstanding leg of a vertical stiffener, may be taken equal to

Correct : C. 1/25th of clear depth of the girder plus 25mm

31. The economical depth d of a web plate in which allowable bearing stress is fb, and the maximum bending moment is M, as suggested by Rawater and Clark, is

Correct : D. d = 4.5 (M/fb)

32. Minimum pitch of the rivets shall not be less than (Where d is gross diameter of rivet)

Correct : C. 2.5 d

33. For steel members exposed to weather and not accessible for repainting, the thickness of steel should not be less than

Correct : C. 8 mm

34. The slenderness ratio of a column supported throughout its length by a masonry wall is

Correct : A. Zero

35. Outstanding length of a compression member consisting of a channel, is measured as

Correct : B. Nominal width of the section

36. The side thrust T on the tie rods provided at the end beam of jack arch of rise R, is calculated from the formula

Correct : C. T = WL/8R

37. Intermediate vertical stiffeners in a plate girder need be provided if the depth of web exceeds

Correct : B. 85 t

38. For the buildings having a low permeability, the internal wind pressure acting normal to the wall and roof surfaces is taken as (Where p is basic wind pressure)

Correct : B. ±0.2 p

39. If is the maximum allowable bending stress in a tension member whose radius of gyration is and depth is 2y, the required cross sectional area is given by

Correct : A. A = My/fr²

40. The load on a lintel is assumed as uniformly distributed if the height of the masonry above it, is upto a height of

Correct : B. 1.25 times the effective span

41. Maximum pitch of rivets, used in steel stacks, is limited to

Correct : B. 10 t

42. According to IS: 800-1962, the coefficient of expansion of steel per degree centigrade per unit length, is taken as

Correct : C. 0.000012

43. If R is the reaction on the bearing plate, the minimum moment of. inertia of the bearing stiffener provided at the support of a plate girder of overall depth D, the maximum thickness of the compression flange T, carrying total load W, is

Correct : B. (D3T/250) × (R/W)

44. As per IS: 800, in the plastic design, which of the following pairs are correctly matched? Working Loads Load factor (i) Dead load 1.7 (ii) Dead Load + imposed load 1.7 (iii) Dead load + load due to wind or 1.3 seismic forces (iv) Dead load + imposed load + load 1.7 due to wind or seismic forces Of these statements

Correct : A. (i) and (ii) are correct

45. Effective length of a column effectively held in position and restrained in direction at both ends, is

Correct : B. 0.67 L

46. Pick up the correct statement from the following:

Correct : D. All the above

47. Effective length of a column effectively held in position and restrained in direction at one end but neither held in position nor restrained in direction at the other end, is

Correct : D. 2 L

48. If the thickness of thinnest outside plate is 10 mm, then the maximum pitch of rivets in tension will be taken as

Correct : B. 160 mm

49. The connection of one beam to another beam by means of an angle at the bottom and an angle at the top, is known as

Correct : C. Seated connection

50. The effective length of a battened strut effectively held in position at both ends but not restrained in direction is taken as

Correct : C. 1.5 L

51. The method of design of steel framework for greatest rigidity and economy in weight, is known as

Correct : C. Fully rigid design

52. For a cantilever beam of length built-in at the support and restrained against torsion at the free end, the effective projecting length is

Correct : B. l = 0.75 L

53. The least permissible clear dimension of the web of thickness t in the panel of a plate girder, is restricted to

Correct : D. 180 t

54. Bearing stiffeners are provided at (i) The supports (ii) The mid span (iii) The point of application of concentrated loads The correct answer is

Correct : C. Both (i) and (iii)

55. Pick up the correct statement from the following:

Correct : D. All the above

56. If d is the distance between the flange angles, the vertical stiffeners in plate girders are spaced not greater than

Correct : C. 1.5 d

57. If d is the distance between the flange angles of a plate girder, vertical stiffeners are provided at a distance not greater than

Correct : B. 1.25 d but not less than 0.33 d

58. A second horizontal stiffener is always placed at the neutral axis of the girder if the thickness of the web is less than

Correct : C. Both (c) and (b)

59. The strength of ISA 125 = 75 × 10 mm used as a tie member with its longer leg connected at the ends by 27 mm diameter rivets, is

Correct : D. 26,075 kg

60. The effect of racking forces is considered in the design of (i) Lateral braces (ii) Chord members The correct answer is

Correct : A. Only (i)

61. For a column of height fixed in position and direction both at its top and bottom, its effective length, is

Correct : C. ½ L

62. A tension member, if subjected to possible reversal of stress due to wind, the slenderness ratio of the member should not exceed

Correct : D. 350

63. Pick up the correct statement from the following:

Correct : D. All the above

64. Under a concentrated load, bearing stress fb in a beam is given by (where b is the length of the bearing plate and h is the depth of the root of the fillet).

Correct : B. fb = W/(b + 2h tw

65. For double angles carrying tension, placed back to back and connected to either side of the gusset plate, the sectional area of the section, is equal to cross sectional area of

Correct : C. The section minus area of rivet holes

66. If fbt and fc are the co-existent bending tensile stress and shear stress in a member, the equivalent stress fc is

Correct : C. fbt² + 3fc²)

67. When a large value of radius of gyration is not requiredChannels are placed back to back

Correct : B. Channel flanges are kept outward

68. Minimum thickness of web in a plate girder, when the plate is accessible and also exposed to weather, is

Correct : B. 6 mm

69. If d is the distance between the flange angles, the vertical stiffeners in plate girders without horizontal stiffeners, are spaced at a distance not less than

Correct : C. 0.33 d

70. To minimize the total cost of a roof truss, the ratio of the cost of truss to the cost of purlins shall be

Correct : B. 2

71. In factory buildings, the horizontal beams spanning between the wall columns supporting a wall covering, are called

Correct : C. Girts

72. A structural member subjected to tensile force in a direction parallel to its longitudinal axis, is generally known as

Correct : D. All the above

73. According to the Unwin's formula, if is thickness of the plate in mm, the nominal diameter of the rivet, is

Correct : C. d = 1.91 t

74. If the area of cross-section of a single angle discontinuous strut is 30 cm2 and allowable working stress corresponding to its slenderness ratio is 625 kg/cm2, the safe load carrying capacity of the member, is

Correct : C. 15 tonnes

75. The minimum thickness of a steel plate, which is directly exposed to weather and is not accessible for cleaning and repainting, should be:

Correct : C. 8 mm

76. For determination of allowable stress in axial compression, Indian Standard Institution has adopted

Correct : D. Secant formula

77. When the axis of load lies in the plane of rivet group, then the most heavily loaded rivet will be the one which moment in any rivet.)

Correct : D. Gives the minimum angle between the two forces Fa and Fm

78. The minimum edge distance of a rivet line connecting two or more plates, is kept equal to 37 mm plus (where t is the thickness in mm of the thinner outside plate).

Correct : B. 4 t

79. Minimum spacing of vertical stiffeners is limited to (Where d is the distance between flange angles)

Correct : B. d/3

80. The rolled steel I-sections are most commonly used as beams because these provide

Correct : D. All the above

81. If P is the wind pressure in kg/cm2 , v is the velocity in km/hour and K is a constant of proportionality, then

Correct : C. P = Kv2

82. As per IS : 875, for the purposes of specifying basic wind velocity, the country has been divided into

Correct : C. 6 zones

83. Study the following statements. (i) Top lateral bracing prevents the sides-way buckling of the chord. (ii) Sway bracing keeps the rectangular shape of the bridge cross-section. (iii) Sway bracing transfers the load from top of end posts to bearings. The correct answer is

Correct : B. Both (i) and (ii)

84. The greatest gauge of long rivets should not exceed (where d is the diameter of the holes).

Correct : D. 8 d

85. The shape factor of an isosceles triangle for bending about the axis parallel to the base is:

Correct : D. all

86. Water pressure in a 80 cm water main is 10 kg/cm2. The minimum thickness of themetal required for the water main, not to be stressed more than 200 kg/cm2, is

Correct : C. 2 cm

87. The beams supporting the steps of a stair are generally known as Headers

Correct : C. Spandrel beams

88. With usual notations of the letters, the shear stress fs at any point of the crosssection is given by

Correct : A. fs =FQ/It

89. If W and L are the total superimposed load and the span of a plate girder in metres, the approximate self weight (W) of the girder, is taken as

Correct : C. M = WL/300

90. Maximum permissible slenderness ratio of a member normally acting as a tie in a roof truss, is

Correct : D. 350

91. The capacity of the smallest pressed steel tank is 1000 litre

Correct : C. 2450 litre

92. When the depth of a plate girder is at least times the depth of vertical leg of the flange angles, the girder is known as deep plate girder, if is

Correct : D. 8

93. If the pitch is 6 cm and rivet value is 4 tonnes, the number of rivets required for a riveted connection carrying an eccentric load of 15 tonnes at a distance of 30 cm from the centre line, is

Correct : B. 8

94. The difference between gross diameter and nominal diameter for the rivets up to 25 mm diameter is

Correct : B. 1.5 mm

95. Pick up the correct statement from the following:

Correct : D. All the above

96. The greatest permissible clear dimension of the web of thickness t in the panel of a plate girder, is restricted to

Correct : D. 270 t

97. The maximum slenderness ratio of a compression member carrying both dead and superimposed load is

Correct : A. 180

98. Effective length of a column effectively held in position at both ends and restrained in direction at one end, is

Correct : C. 0.85 L

99. As per IS : 800, for compression flange, the outstand of flange plates should not exceed

Correct : B. 16 t

100. If the unsupported length of a stanchion is 4 metres and least radius of gyration of its cross-section is 5, the slenderness ratio of the stanchion, is

Correct : C. 80