1. What is the load factor considered for steel structures when combination of dead load, imposed load and earthquake load is considered?
a) 1.5
b) 1.3
c) 1.2
d) 1.7
Discussion
Explanation: In plastic design of steel structures, load factor is 1.3 when combination of dead load, imposed load and earthquake load is considered i.e. 1.3(DL +/- IL +/- EL ).
2. For earthquake loads, axially loaded members have to resist ________________
a) tension only
b) compression only
c) both tension and compression
d) bending moment
Discussion
Explanation: Earthquake are cyclic and induce reversal of stresses. Hence as per seismic philosophy, axially loaded members have to resist both tension and compression.
3. For earthquake loads, beams are designed to resist ________________
a) tension only
b) positive and negative bending moments
c) compression only
d) torsion
Discussion
Explanation: Beams are designed to resist positive and negative bending moments at the same section for earthquake loads.
4. Structures are designed for seismic forces which is ____ than expected seismic force.
a) lesser
b) greater
c) equal to
d) seismic forces are not considered
Discussion
Explanation: Structures are designed for seismic forces which is less than expected seismic force under strong earthquakes, if the structures were to remain linearly elastic.
5. Which of the following factors does not influence earthquake resistance design?
a) geographical location of structure
b) wind of location
c) site soil
d) strength of structure
Discussion
Explanation: The factors which influence earthquake resistance design are : (i) geographical location of structure, (ii) site soil and foundation condition, (iii) importance of structure, (iv) dynamic characteristics of structure such as strength, stiffness, ductility and energy dissipation factor.
6. Structures should be designed such that ___________
a) Minor and frequent earthquakes can collapse the structure
b) Moderate earthquakes can cause damage to the structure
c) Major earthquakes should not cause any damage to the structure and the structure should be functional
d) Minor earthquake should not cause any damage to the structure and the structure should be functional
Discussion
Explanation: As per IS 1893, the following seismic philosophy is adopted
(i) Minor and frequent earthquakes should not cause any damage to the structure
(ii) Moderate earthquake should not cause significant structural damage but could have some non structural damage(the structure should become operational once the damage is repaired)
(iii) Major and infrequent earthquake should not cause collapse( structure will be dysfunctional for further use, but will stand so that people can be evacuated and property can be recovered).
7. Which of the following assumption is correct for earthquake design resistant structure?
a) Earthquake will not occur simultaneously with wind
b) Earthquake will occur simultaneously with maximum flood
c) Earthquake will occur simultaneously with maximum sea waves
d) Earthquake will occur simultaneously with wind
Discussion
Explanation: As per IS 1893, it is assumed that earthquake is not likely to occur simultaneously with wind or maximum flood or maximum sea waves.
8. Which analysis is used to obtain design seismic force?
a) Elastic Analysis
b) Plastic Analysis
c) Dynamic Analysis
d) Both elastic and plastic analysis
Discussion
Explanation: Dynamic analysis is used to obtain design seismic force, and its distribution to different level along the height of the building and to various lateral load resisting members.
9. What is structural response factor?
a) factor denoting the acceleration response spectrum of the structure subjected to earthquake ground vibrations
b) factor by which the actual base shear force is reduced
c) factor to obtain the design spectrum
d) factor used to obtain the design seismic force
Discussion
Explanation: Structural response factor (Sa/g) is the factor denoting the acceleration response spectrum of the structure subjected to earthquake ground vibrations. It depends on natural period of vibration and damping of the structure. Response Reduction Factor(R) is the factor by which the actual base shear force is reduced. Zone Factor(Z) is factor to obtain the design spectrum. Importance Factor (I) is the factor used to obtain the design seismic force.
10. Internal pressure coefficient in a building is positive if acting from ________ and external pressure coefficient in a building is positive if acting from ___________
a) outside to inside, inside to outside
b) inside to outside, outside to inside
c) outside to inside, outside to inside
d) inside to outside, inside to outside
Discussion
Explanation: Internal pressure coefficient in a building is positive if acting from inside to outside and external pressure coefficient in a building is positive if acting from outside to inside. The pressure depends on degree of permeability of cladding and direction of wind.