Design of Steel Structures MCQs - Methods and Assumptions of Analysis

1. The design action effects for design basis earthquake loads is obtained by _____________
a) Elastic Analysis
b) Plastic Analysis
c) Advanced Analysis
d) Dynamic Analysis

  Discussion

Answer: a
Explanation: The design action effects for design basis earthquake loads is obtained by elastic analysis. The maximum credible earthquake load can be assumed to correspond to load at which significant plastic hinges are formed and shall be obtained by plastic analysis.

2. What is non-sway frame?
a) transverse displacement of one end of member relative to other end is not effectively prevented
b) longitudinal displacement of one end of member relative to other end is not effectively prevented
c) transverse displacement of one end of member relative to other end is effectively prevented
d) longitudinal displacement of one end of member relative to other end is effectively prevented

  Discussion

Answer: c
Explanation: In non-sway frame, transverse displacement of one end of member relative to other end is effectively prevented. Example : in triangulated frames and trusses, in plane stiffeners is provided by bracings or by shear walls, etc.

3. What is sway frame?
a) longitudinal displacement of one end of member relative to other end is not effectively prevented
b) transverse displacement of one end of member relative to other end is effectively prevented
c) longitudinal displacement of one end of member relative to other end is effectively prevented
d) transverse displacement of one end of member relative to other end is not effectively prevented

  Discussion

Answer: d
Explanation: In sway frame, transverse displacement of one end of member relative to other end is not effectively prevented. Such members and frames occur in structure which depend on flexural action of members to resist lateral loads and sway.

4. Which of the following is true about rigid construction?
a) connections between members at their junction does not have sufficient rigidity
b) connections between members at their junction have sufficient rigidity
c) members are not connected
d) connection between members at junction will not resist any moment

  Discussion

Answer: b
Explanation: In rigid construction, connections between members at their junction have sufficient rigidity to hold angles between members connected at joint, unchanged under load.

5. In simple construction, connection between members at their junction will __________
a) resist moment
b) resist force
c) not resist force
d) not resist moment

  Discussion

Answer: d
Explanation: In simple construction, connection between members at their junction will not resist any appreciable moment and shall be assumed to be hinged

6. What percent of factored load is notional horizontal force?
a) 0.5%
b) 1%
c) 10%
d) 20%

  Discussion

Answer: a
Explanation: Notional horizontal force = 0.5% of factored dead load + vertical imposed load at that level. Notional horizontal force are applied to analyse a frame subjected to gravity loads, considering sway stability of frame.

7. Which of the following is not an assumption of first order elastic analysis of rigid jointed frame?
a) materials behave linearly
b) yielding effects can be ignored
c) member instability effects cannot be ignored
d) frame instability effects can be ignored

  Discussion

Answer: c
Explanation: The following are the assumptions of first order elastic analysis of rigid jointed frame : (i) materials behave linearly, (ii) yielding effects can be ignored, (iii) member instability effects such as those caused by axial compression can ignored, (iv) frame behaves linearly frame instability effects such as those caused by moments due to horizontal frame deflection, etc can be ignored.

8. Basic objective of second order elastic analysis is :
a) to calculate external force equilibrium in deformed geometry of structure
b) to calculate internal force equilibrium in deformed geometry of structure
c) to calculate external force equilibrium in undeformed geometry of structure
d) to calculate internal force equilibrium in undeformed geometry of structure

  Discussion

Answer: b
Explanation: Basic objective of second order elastic analysis is to calculate internal force equilibrium in deformed geometry of structure. In this P-Δ effect is also considered.

9. First order analysis yields bending moment equal to those for a _____
a) cantilever beam
b) continuous beam
c) fixed beam
d) simply supported beam

  Discussion

Answer: d
Explanation: First order analysis yields bending moment equal to those for a simply supported beam since material and frame are assumed to behave linearly and member instability effects and frame instability effects can be ignored.

10. When plastic analysis is used, the yield stress of grade of steel used shall not exceed _____
a) 250 MPa
b) 500 MPa
c) 450 MPa
d) 800 MPa

  Discussion

Answer: c
Explanation: When plastic analysis is used, the yield stress of grade of steel used shall not exceed 450 MPa and the stress strain distribution of steel shall not be significantly different from those obtained for steels complying with IS 2062.