Structural Analysis Multiple Choice Questions on “Loading Conditions for Strength Design”.
1. By this method, the load factors are:-
a) Smaller than 0.5
b) 0.5 < 0.75
c) 0.75 < 1
d) Larger than 1
Answer: d
Clarification: Resulting factored load are used to have a design to support the ultimate loads. So, factors are > 1.
2. Purpose of load factors is to account for:-
a) Lapse in designing
b) Lapse in constructing
c) Lapse in funding
d) Lapse in predicting magnitudes of dead or live load
Answer: d
Clarification: It accounts for uncertainties related to estimation of magnitude of dead or live loads.
3. Load factors used for live load are _____ than that used for dead loads.
a) Smaller
b) Larger
c) Depends upon case
d) Depends upon loading
Answer: b
Clarification: Magnitudes of dead loads can be predicted more accurately than magnitudes of live loads.
4. The load factor to be used with strength design depends upon:-
a) Amount of load
b) Is constant
c) Depends upon engineer
d) Depends upon type of structure
Answer: d
Clarification: Load factors are determined statistically and type of structures is considered.
5. Which of the following load combinations is recommended for building structures?
a) D + F
b) 1.4D + F
c) D + 1.4F
d) 1.4(D + F)
Answer: d
Clarification: These are mentioned inn ASCE 7-02 and can be verified from there.
6. When larger dead loads tend to reduce the effects of other loads, what is the recommended factor that is used with the dead load?
a) 0.9
b) 0.8
c) 0.7
d) 0.6
Answer: a
Clarification: 0.9D + 1.6W + 1.6H & 0.9D + 1E + 1.6H are the examples.
7. Load factors do not vary in relation to the seriousness of failure.
Is the above statement true or false?
a) True
b) False
Answer: a
Clarification: Load factors were developed on the assumption that designers would consider the seriousness of all the possible failure in specifying loads. Load factors are minimum values.
8. In the equation U-0.9D + 1.6W + 1.6H, what is the load factor for H if the structural action of H counteracts that due to W or E?
a) 0.1
b) 0.05
c) 0.005
d) 0
Answer: d
Clarification: H should be included in design resistance here as lateral earth pressure opposes action of other forces.
9. In case of wind and seismic loads, how many times do we have to apply applicable equations?
a) 1
b) 2
c) 3
d) 4
Answer: b
Clarification: Wind and seismic loads can have two values depending upon direction of those forces, and it is possible for the sign of them to be different.