1. In cases of girders, It is assumed that it:-
a) Does support axial force
b) Does not support axial force
c) Does not support shear force
d) Does not support axial and shear force
Explanation: It is one of the three assumptions made as degree of indeterminacy of a column-girder system is 3.
2. Portal frames are frequently used in a building to:-
a) Transfer vertical forces
b) Transfer moment
c) Transfer horizontal forces
d) It is a zero it is used to transfer horizontal force applied at top of frame to foundation
Explanation: Portal frames are frequently used in a building to transfer horizontal forces
3. Which of the following supports are not used in portals?
a) Fixed
b) Pin
c) partial
d) Roller
Explanation: Portals are either fixed, pin or partial supported.
4. What is the degree of indeterminacy of a pin supported portal frame?
a) 1
b) 2
c) 3
d) 4
Explanation: It has 4 unknowns and as usual 3 equilibrium equations
5. Where is point of inflection located in top girder in a pin supported portal frame?
a) At one of the ends
b) At both ends
c) At center of beam
d) Inflection point is not present
Explanation: On drawing elastic defection diagram of a portal frame, we can find out the location of point of inflection.
6. What is the relation between shear at the base of each columns of a portal frame which is pin supported?
a) They are equal
b) One is double of other
c) One is triple of other
d) Depends upon magnitude of load applied
Explanation: On assuming a pin at midpoint of top girder we can easily show that both shears are equal by conserving force and moment
7. What is the degree of indeterminacy of a fixed supported portal frames?
a) 1
b) 2
c) 3
d) 4
Explanation: There are a total of 6 unknowns and three equilibrium equations involved in such cases.
8. Where is point of inflections of vertical members in a portal frame located at?
a) At centre
b) Depends upon magnitude of load
c) Depends upon relative lengths of vertical member
d) There is no inflection point in vertical members
Explanation: If vertical members are equal in length then inflection points will be in centre. Otherwise its location would vary.
9. What is the relation between shear at the base of each columns of a portal frame which is fixed supported (given length of columns are equal)?
a) They are equal
b) One is double of other
c) One is triple of other
d) Depends upon magnitude of load applied
Explanation: On assuming a pin at midpoint of each column we can easily show that both shears are equal by conserving force and moment
10. At what distance base is point of inflection assumed in column of a portal frame which is supported by partially fixed supports (length of column is L)?
a) L
b) L/2
c) L/3
d) L/4
Explanation: Since, it will lie somewhere between end point and L/2, generally it is assumed to lie at a distance of L/3 from base.