1000+ Design of Steel Structures Multiple Choice Question Answer [Solved]

1. The critical stress on a column for elastic buckling given by Euler's formula, is
A. f_c = ?²E/(I/r)²
B. f_c = (I/r)²/ ?E
C. f_c = (I/r)/ ?E
D. f_c = ?²E/(I/r)
Answer : A

2. The effective length of a double angle strut with angles placed back to back and connected to both the sides of a gusset plate, by not less than two rivets, is
A. 0.5 L
B. 0.67 L
C. 0.85 L
D. 2 L
Answer : C

3. A column splice is used to increase
A. Length of the column
B. Strength of the column
C. Cross-sectional area of the column
D. None of these
Answer : A

4. A single angle in tension is connected by one leg only. If the areas of connecting and outstanding legs are respectively a and b, net effective area of the angle, is
A. a - [b/{1 + 0.35 (b/a)}]
B. a + [b/{1 + 0.35 (b/a)}]
C. a - [b/{1 + 0.2 (b/a)}]
D. a + [b/{1 + 0.2 (b/a)}]
Answer : B

5. The effect of racking forces is considered in the design of (i) Lateral braces (ii) Chord members The correct answer is
A. Only (i)
B. Only (ii)
C. Both (i) and (ii)
D. None of the above
Answer : A

6. IS : 800 - 1971 recommends that in a splice plate the number of rivets carrying calculated shear stress through a packing greater than 6 mm thick, is to be increased by 2.5% for every
A. 1.00 mm thickness of packing
B. 1.50 mm thickness of packing
C. 2.0 mm thickness of packing
D. 2.50 mm thickness of packing
Answer : C

7. Pick up the correct statement from the following:
A. The slenderness ratio of lacing bars for compression members should not exceed 145
B. The minimum width of lacing bar connected with rivets of nominal diameter 16 mm, is kept 50 mm
C. The minimum thickness of a flat lacing bar is kept equal to onefortieth of its length between inner end rivets
D. All the above
Answer : D

8. A steel beam supporting loads from the floor slab as well as from wall is termed as
A. Stringer beam
B. Lintel beam
C. Spandrel beam
D. Header beam
Answer : C

9. In a built up beam actual bending compressive stress f_bc is given by (when y₁ is the distance of the edge of the beam from the neutral axis).
A. f_bc = (M/I_xx) × y?
B. f_bc = (I_xx/M) × y?
C. f_bc = (I_xx/M) + y?
D. f_bc = (M/I_xx) + y?
Answer : A

10. The beam outside a wall upto floor level above it, is known as
A. Rafter
B. Purlin
C. Spandrel beam
D. Lintel
Answer : C

11. The maximum permissible slenderness ratio of compression member carrying dead and superimposed load, is
A. 180
B. 200
C. 250
D. 350
Answer : A

12. Generally the purlins are placed at the panel points so as to avoid
A. Axial force in rafter
B. Shear force in rafter
C. Deflection of rafter
D. Bending moment in rafter
Answer : D

13. If the thickness of a structural member is small as compared to its length and width, it is classified as
A. One dimensional
B. Two dimensional
C. Three dimensional
D. None of these
Answer : B

14. 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
A. 26,000 kg
B. 26,025 kg
C. 26,050 kg
D. 26,075 kg
Answer : D

15. If f_bt and f_c are the co-existent bending tensile stress and shear stress in a member, the equivalent stress f_c is
A. ?(f_bt² + f_c²)
B. ?(f_bt² + ½f_c²)
C. ?(f_bt² + 3f_c²)
D. ?(f_bt² - 3f_c²)
Answer : C

16. The minimum width B of a solid casing for a cased beam, is equal to
A. B = b + 25 mm
B. B = b + 50 mm
C. B = b + 75 mm
D. B = b + 100 mm
Answer : D

17. Allowable working stress corresponding to the slenderness ratio of double angles placed back to back and connected to one side of a gusset plate, is reduced to
A. 50 %
B. 60 %
C. 70 %
D. 80 %
Answer : D

18. The effective length of a battened column is increased by
A. 5 %
B. 10 %
C. 15 %
D. 20 %
Answer : B

19. The greatest gauge of long rivets should not exceed (where d is the diameter of the holes).
A. 2 d
B. 4 d
C. 6 d
D. 8 d
Answer : D

20. The maximum spacing of vertical stiffeners is
A. 1.33 d
B. 1.25 d
C. 1.5 d
D. 1.75 d Where d is the distance between flange angles
Answer : C

21. The external wind pressure acting on a roof depends on
A. Degree of permeability of roof
B. Slope of roof
C. Both (A) and (B)
D. None of the above
Answer : B

22. Which of the following conditions is to be satisfied both in elastic and plastic analysis?
A. Equilibrium condition
B. Yield condition
C. Plastic moment condition
D. Mechanism condition
Answer : A

23. A simply supported beam carrying a central load, will be safe in deflection if the ratio of its span to depth, is
A. < 19
B. < 24
C. > 19
D. > 24
Answer : B

24. Which of the following sections should preferably be used at places where torsion occurs?
A. Angle section
B. Channel section
C. Box type section
D. Any of the above
Answer : C

25. For the buildings having a low permeability, the internal wind pressure acting normal to the wall and roof surfaces is taken as
A. Zero
B. ±0.2 p
C. ± 0.5 p
D. ±0.7 p Where p is basic wind pressure
Answer : B

26. The slenderness ratio of a column supported throughout its length by a masonry wall is
A. Zero
B. 10
C. 100
D. Infinity
Answer : A

27. The live load for a sloping roof with slope 15°, where access is not provided to roof, is taken as
A. 0.65 kN/m²
B. 0.75 kN/m²
C. 1.35 kN/m²
D. 1.50 kN/m²
Answer : A

28. The ratio of plastic section modulus to elastic section modulus
A. Is equal to 1
B. Is always less than 1
C. Is always greater than 1
D. Can be less than 1
Answer : C

29. The stress in the wall of a thin cylinder subjected to internal pressure, is
A. Hoop compression
B. Shear
C. Torsional shear
D. Hoop tension
Answer : D

30. The spans are considered approximately equal if the longest span does not exceed the shortest span by more than
A. 5 %
B. 10 %
C. 15 %
D. 20 %
Answer : C

31. In case of plastic design, the calculated maximum shear capacity of a beam as per IS: 800 shall be
A. 0.55 Aw.fy
B. 0.65 Aw.fy
C. 0.75 Aw.fy
D. 0.85 Aw.fy Where, Aw = effective cross-sectional area resisting shear fy = yield stress of the steel
Answer : A

32. For steel members exposed to weather and not accessible for repainting, the thickness of steel should not be less than
A. 4.5 mm
B. 6 mm
C. 8 mm
D. 10 mm
Answer : C

33. Under a concentrated load, bearing stress f_b 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).
A. f_b = W/(b + h?3)t_w
B. f_b = W/(b + 2h?3)t_w
C. f_b = W/(b + 2h?2)t_w
D. f_b = W/(b + h?2)t_w
Answer : B

34. The actual thickness of butt weld as compared to the thickness of plate is usually
A. More
B. Less
C. Equal
D. None of the above
Answer : A

35. The economical depth d of a web plate in which allowable bearing stress is f_b, and the maximum bending moment is M, as suggested by Rawater and Clark, is
A. d = ?(M/f_b)
B. d = 1.5 ?(M/f_b)
C. d = 2.5 ?(M/f_b)
D. d = 4.5 ?(M/f_b)
Answer : D

36. The mechanism method of plastic analysis satisfies
A. Equilibrium and mechanism conditions
B. Equilibrium and plastic moment conditions
C. Mechanism and plastic moment conditions
D. Equilibrium condition only
Answer : A

37. The sway bracing is designed to transfer
A. 2Vi % of the top panel wind load to bottom bracing
B. 10% of the top panel wind load to bottom bracing
C. 25% of the top panel wind load to bottom bracing
D. 50% of the top panel wind load to bottom bracing
Answer : D

38. In case of timber structures, the form factor for solid circular crosssection is taken as
A. 1.18
B. 1.414
C. 1.67
D. 1.81
Answer : A

39. Hudson's formula gives the dead weight of a truss bridge as a function of
A. Bottom chord area
B. Top chord area
C. Effective span of bridge
D. Heaviest axle load of engine
Answer : A

40. To the calculated area of cover plates of a built-up beam, an allowance for rivet holes to be added, is
A. 10 %
B. 13 %
C. 15 %
D. 18 %
Answer : B

41. The maximum axial load which is just sufficient to keep a column in a small deflected shape, is called
A. Crippling load
B. Buckling load
C. Critical load
D. All the above
Answer : D

42. A riveted joint may experience
A. Shear failure
B. Shear failure of plates
C. Bearing failure
D. All the above
Answer : D

43. 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
A. Overall depth
B. Clear depth
C. Effective depth
D. None of these
Answer : B

44. In moment resistant connections, the moment resistance of riveted connection depends upon
A. Shear in rivets
B. Compression in rivets
C. Tension in rivets
D. Strength of rivets in bearing
Answer : C

45. In the virtual work method, the virtual quantity is
A. Displacement
B. Load
C. Slope
D. Moment
Answer : A

46. In a gusseted base, when the end of the column is machined for complete bearing on the base plate, then the axial load is assumed to be transferred to base plate
A. Fully by direct bearing
B. Fully through fastenings
C. 50% by direct bearing and 50% through fastenings
D. 75% by direct bearing and 25% through fastenings
Answer : C

47. The effective length of a compression member of length L held in position at both ends but not restrained in direction, is
A. L
B. 0.67 L
C. 0.85 L
D. 1.5 L
Answer : A

48. Shear buckling of web in a plate girder is prevented by using
A. Vertical intermediate stiffener
B. Horizontal stiffener at neutral axis
C. Bearing stiffener
D. None of the above
Answer : A

49. According to IS Specifications, the maximum pitch of rivets in compression is
A. Lesser of 200 mm and 12 t
B. Lesser of 200 mm and 16 t
C. Lesser of 300 mm and 32 t
D. Lesser of 3 00 mm and 24 t Where t is thickness of thinnest outside plate or angle
Answer : A

50. Factor of safety is the ratio of
A. Yield stress to working stress
B. Tensile stress to working stress
C. Compressive stress to working stress
D. Bearing stress to working stress
Answer : A