1000+ Design of Steel Structures MCQ for SSC JHT [Solved]

1. If the moment of inertia of a section about its axis is I and its effective sectional area is A, its radius of gyration r about the axis, is
A. r = I/A
B. r = ?(I/A)
C. r = ?(I/A)
D. r = ?(A/I)
Answer : B

2. When the axis of load lies in the plane of rivet group, then the most heavily loaded rivet will be the one which (Where, Fa is the load shared by each rivet due to axial load and Fm is the shearing load due to moment in any rivet.)
A. Is at the maximum distance from CG of the rivet group
B. Is at the minimum distance from CG of the rivet group
C. Gives the maximum angle between the two forces Fa and Fm
D. Gives the minimum angle between the two forces Fa and Fm
Answer : D

3. The allowable tensile stress in structural mild steel plates for steel tank is assumed as
A. 95.0 MPa on net area
B. 105.5 MPa on net area
C. 105.5 MPa on gross area
D. 150.0 MPa on gross area
Answer : B

4. As per IS : 800, for compression flange, the outstand of flange plates should not exceed
A. 12 t
B. 16 t
C. 20 t
D. 25 t Where t = thickness of thinnest flange plate
Answer : B

5. 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

6. 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
A. (i) and (ii) are correct
B. (i), (ii) and (iii) are correct
C. (ii) and (iii) are correct
D. Only (i) is correct
Answer : A

7. 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

8. 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

9. Lug angle is
A. Used with single angle member
B. Not used with double angle member
C. Used with channel member
D. All the above
Answer : D

10. The effective length of a fillet weld should not be less than
A. Two times the weld size
B. Four times the weld size
C. Six times the weld size
D. Weld size
Answer : B

11. In factory buildings, the horizontal beams spanning between the wall columns supporting a wall covering, are called
A. Stringers
B. Trimmers
C. Girts
D. Lintels
Answer : C

12. 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

13. 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

14. The portal bracing in a truss bridge is used to
A. Transfer load from top of end posts to bearings
B. Keep the rectangular shape of the bridge cross-section
C. Stiffen the structure laterally
D. Prevent the sides-way buckling of top chord
Answer : A

15. The mechanism method and the statical method give
A. Lower and upper bounds respectively on the strength of structure
B. Upper and lower bounds respectively on the strength of structure
C. Lower bound on the strength of structure
D. Upper bound on the strength of structure
Answer : B

16. 2.Compression members composed of two channels back-to-back and separated by a small distance are connected together by riveting so that the minimum slenderness ratio of each member between the connections, does not exceed
A. 40
B. 50
C. 60
D. 70
Answer : A

17. To minimize the total cost of a roof truss, the ratio of the cost of truss to the cost of purlins shall be
A. 1
B. 2
C. 3
D. 4
Answer : B

18. In the cross-section of a weld, throat is the
A. Minimum dimension
B. Average dimension
C. Maximum dimension
D. None of the above
Answer : A

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

20. The critical stress on a column for elastic buckling given by Euler's formula, is br>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

21. 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
A. 60
B. 70
C. 80
D. 100
Answer : C

22. When a tension member is made of four angles with a plate as a web, the allowance for holes is made as
A. Two holes for each angle and one hole for the web
B. One hole for each angle and one hole for the web
C. One hole for each angle and two holes for the web
D. Two holes for each angle and two holes for the web
Answer : C

23. If the depth of the section of an upper column is smaller than the lower column
A. Filler plates are provided with column splice
B. Bearing plates are provided with column splice
C. Filler plates and bearing plates are provided with column splice
D. None of these
Answer : D

24. For a cantilever beam of length L built-in at the support and restrained against torsion at the free end, the effective projecting length l is
A. l = 0.7 L
B. l = 0.75 L
C. l = 0.85 L
D. l = 0.5 L
Answer : B

25. Bearing stiffener in a plate girder is used to
A. Transfer the load from the top flange to the bottom one
B. Prevent buckling of web
C. Decrease the effective depth of web
D. Prevent excessive deflection
Answer : B

26. The allowable shear stress in the web of mild steel beams decreases with
A. Decrease in h/t ratio
B. Increase in h/t ratio
C. Decrease in thickness
D. Increase in height Where 'h' is height and t is thickness
Answer : B

27. Slenderness ratio of a compression member is
A. Moment of inertia/Radius of gyration
B. Effective length/Area of cross-section
C. Radius of gyration/Effective length
D. Radius of gyration/ Area of cross-section
Answer : C

28. Pick up the correct statement from the following:
A. Loaded columns are supported on column bases
B. Column bases transmit the column load to the concrete foundation
C. Column load is spread over a large area on concrete
D. All the above
Answer : D

29. 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
A. M = WL/100
B. M = WL/200
C. M = WL/300
D. M = WL/400
Answer : C

30. 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

31. 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

32. The moment of the couple set up in a section of a beam by the longitudinal compressive and tensile force, is known as
A. Bending moment
B. Moment of resistance
C. Flexural stress moment
D. None of these
Answer : B

33. Other conditions being same, the load factor in indeterminate structures is
A. Equal to load factor in determinate structures
B. More than the load factor in determinate structures
C. Less than the load factor in determinate structures
D. Unpredictable
Answer : B

34. For eccentrically loaded columns, the bending factor is
A. Cross-sectional area of column/Radius of gyration
B. Radius of gyration/Cross-sectional area of column
C. Cross-sectional area of column/Section modulus of the section
D. Section modulus of the section/Cross-sectional area of column
Answer : C

35. 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

36. Efficiency of a riveted joint is defined as the ratio of
A. Least strength of a riveted joint to the strength of solid plate
B. Greatest strength of a riveted joint to the strength of solid plate
C. Least strength of a riveted plate to the greatest strength of the riveted joint
D. All the above
Answer : D

37. For the steel member exposed to weather and accessible for repainting, the thickness of steel should not be less than (accepting the webs of Indian Standard rolled steel joists and channels).
A. 4 mm
B. 6 mm
C. 8 mm
D. 10 mm
Answer : B

38. The distance measured along one rivet line from the centre of a rivet to the centre of adjoining rivet on an adjacent parallel rivet line, is called
A. Pitch of rivet
B. Gauge distance of rivet
C. Staggered pitch
D. All the above
Answer : C

39. The use of tie plates in laced columns is
A. Prohibited
B. Not prohibited
C. Permitted at start and end of lacing system only
D. Permitted between two parts of the lacing
Answer : C

40. The number o seismic zones in which the country has been divided is
A. 3
B. 5
C. 6
D. 7
Answer : B

41. Pick up the correct statement from the following:
A. When the gauge distance is larger than the pitch, the failure of the section may occur in a zig-zag line
B. When the gauge distance is smaller than the pitch, the failure of the section may occur in a straight right angle section through the centre of rivet holes
C. When the gauge distance and pitch are both equal, the failure to the section becomes more likely as the diameter of the holes increases
D. All the above
Answer : D

42. The risk coefficient k, depends on
A. Mean probable design life of structures
B. Basic wind speed
C. Both (A) and (B)
D. None of the above
Answer : C

43. For a rectangular section, the ratio of the maximum and average shear stresses, is
A. 1.5
B. 2.0
C. 2.5
D. 3.5
Answer : A

44. The elastic strain for steel is about
A. 1/12 of strain at the initiation of strain hardening and about 1/120 of maximum strain
B. 1/2 of strain at the initiation of strain hardening and about 1/12 of maximum strain
C. 1/12 of strain at the initiation of strain hardening and 1/200 of maximum strain
D. 1/24 of strain at the initiation of strain hardening and about 1/200 of maximum strain
Answer : C

45. Bulb angles are used in
A. Column building
B. Bridge building
C. Ship building
D. Water tank building
Answer : C

46. Rise of a Jack arch is kept about
A. 1/2 to 1/3 of the span
B. 1/3 to 1/4 of the span
C. 1/4 to 1/8 of the span
D. 1/8 to 1/12 of the span
Answer : D

47. Angle of inclination of the lacing bar with the longitudinal axis of the column should preferably be between
A. 10° to 30°
B. 30° to 40°
C. 40° to 70°
D. 90°
Answer : C

48. The deflection of beams may be decreased by
A. Increasing the depth of beam
B. Increasing the span
C. Decreasing the depth of beam
D. Increasing the width of beam
Answer : A

49. 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

50. In a truss girder of a bridge, a diagonal consists of mild steel flat 4001.S.F. and carries a pull of 80 tonnes. If the gross-diameter of the rivet is 26 mm, the number of rivets required in the splice, is
A. 6
B. 7
C. 8
D. 9
Answer : C