This set of Repair and Rehabilitation of Structures Multiple Choice Questions & Answers (MCQs) focuses on “Provision of Movement Joint in Structures”.
1. Horizontal joint about _______ in width should be provided between top of panel or partition walls.
a) 10mm
b) 20mm
c) 15mm
d) 25mm
View Answer
Explanation: A horizontal joint about 10mm width is provided between the top of the panel or partition walls and this gap is filled with a mastic compound finished filled with elastic sealant or it is filled with weak mortar to 3 cm depth on the external face and is left open in the internal face.
2. ________ reinforcements are provided in masonry partitions having length to height ratio exceeding the value 2.
a) Diagonal
b) Vertical
c) Horizontal
d) Straight
View Answer
Explanation: When the length to height ratio exceeds 2, then horizontal reinforcements are provided in masonry partitions and this reinforced strip can accommodate differential movement elastically thereby resisting the crack formation to some extent.
3. Garden walls and parapet walls are examples of _______
a) Shear
b) Free standing
c) RC
d) Panel
View Answer
Explanation: Free standing walls are those that stand alone along its length. Long walls that are connected at their ends to another structure can also structurally behave as free standing walls. Garden walls and parapet walls are the examples of free standing walls.
4. Diagonal cracks are formed due to __________ thrust.
a) downward
b) upward
c) sideward
d) uniform
View Answer
Explanation: Diagonal cracks that are tapering and wider at the bottom are caused due to upward thrust which is exerted by the roots of the trees and plants which are growing in the vicinity of the wall.
5. Arching up and cracking of the coping stone occurs in ________ wall.
a) compound
b) free standing
c) main
d) shear
View Answer
Explanation: When the compound walls are built between two heavy structures and they act as rigid restraints leading to the formation of arching and cracking of coping stone when expansion joints are not provided.
6. Cracks that are up to 1.5mm width generally needs no repairing if the bricks used are of non-absorbing type.
a) True
b) False
View Answer
Explanation: When cracks up to 1.5mm occur in the non-absorbing type of brick then repairing is needed because possibility of rain water penetration in these bricks is larger leading to the formation of crack. And so, repairing is needed in this case.
7. Cracks in exposed RC member like sunshades and balconies are controlled by providing expansion joint at an interval of __________
a) 2m
b) 6m
c) 10m
d) 15m
View Answer
Explanation: Expansion joints are provided in exposed RC member like sunshades and balconies at an interval of 6m so as to arrest the formation of cracks due to shrinkage in concrete.
8. When rendering and plastering are done too long after casting of concrete then shrinkage cracks occur.
a) True
b) False
View Answer
Explanation: Plastering should be done immediately after the removal of shuttering by hacking and roughening of the surface and then followed by the application of cement slurry on the concrete surface to enhance the bondage. When plastering is delayed then it leads to the formation cracks.
9. When doors and windows are provided in half brick masonry walls then the hold fast should be at least ____ cm.
a) 15
b) 25
c) 20
d) 30
View Answer
Explanation: The hold fast should be of 25 cm when the doors and windows are provided in half brick masonry walls if not continuous opening and closing of doors and windows may lead to the slackness between the hold fast and frames which results in the formation of cracks.
10. Corner cracks occurs in the panels of concrete ______________
a) flooring
b) ceiling
c) walls
d) columns
View Answer
Explanation: Corner cracks occur in the panels of concrete flooring due to the curling of corners encountered by the action of differential shrinkage between the top and bottom of the slab.
Sanfoundry Global Education & Learning Series – Repair and Rehabilitation of Structures.
To practice all areas of Repair and Rehabilitation of Structures, here is complete set of Multiple Choice Questions and Answers.