1.Which of the following should be used for construction in brick-backed ashlar masonry?
a) Cement mortar
b) Lime mortar
c) Mud mortar
d) Cement concrete
Explanation: In brick-backed ashlar masonry, cement mortar should be used for construction. Cement mortar is used to form joints of uniform thickness and imparts strength to the masonry.
2. In rubble-backed brick masonry, each alternate course comprises of a __________
a) Header
b) Stretcher
c) Bat
d) Quoin header
Explanation: In rubble-backed brick masonry, each alternate course comprises of a quoin header. It is defined as a corner on the face side of a wall.
3. In which of the following types, stone marble may be used for making stone tiles?
a) Brick-backed ashlar masonry
b) Brick-backed stone slab facing
c) Rubble-backed brick masonry
d) Stone-backed masonry
Explanation: In brick-backed ashlar masonry, alternate courses of ashlar are present. In brick-backed stone slab facing, stone marble may be used for making stone tiles.
4. In brick-backed stone slab facing, it is advisable to use steel cramps for connecting the facing and backing.
a) True
b) False
Explanation: Brick-backed stone slab facing is composed of bricks that are laid in courses with proper bonds. In brick-backed stone slab facing, it is advisable to use metal cramps for connecting the facing and backing.
5. According to the recommendations laid by the Concrete Association of India, what should be the least strength of the blocks used in concrete masonry?
a) 3 N/mm2
b) 4 N/mm2
c) 2 N/mm2
d) 5 N/mm2
Explanation: Concrete Association of India recommends that the strength of the blocks used in concrete masonry should be at least 3 N/mm2 and the recommended size of common blocks used in cement concrete masonry are 39 cm x 19 cm x 30 cm; 39 cm x 19 cm x 20 cm and 39 cm x 19 cm x 10 cm.
6. In concrete masonry, a hollow concrete block has a core-void area greater than __________ of the gross area.
a) 20%
b) 15%
c) 30%
d) 25%
Explanation: Concrete masonry uses two types of cement concrete blocks for the construction of walls – hollow concrete block and solid concrete block. A hollow concrete block has a core-void area greater than 25% of the gross area.
7.In which of the following surface finishes, finishing material such as marble is used on the facing side of the block?
a) Common finished surface
b) Glazed finish
c) Specially faced finish
d) Colored finish
Explanation: Common finished surface is obtained by mixing appropriate aggregates. Glazed finish is used to give a shiny appearance. Colored finish is obtained by adding various colored pigments to the concrete mix to impart different colors whereas in the specially faced finish, finishing material such as marble, is used on the facing side of the block.
8. While manufacturing the concrete masonry bricks, the cement-aggregate ratio should not be thinner than __________
a) 1:6
b) 1:3
c) 3:4
d) 1:4
Explanation: While manufacturing the concrete masonry bricks, the cement-aggregate ratio should not be thinner than 1:6. The aggregate should have a mixture with the proportion of fine aggregate being 60% and coarse aggregate being 40%.
9. Which of the following surface finishes is used for decorative works?
a) Slumped finish
b) Colored finish
c) Specially faced finish
d) Glazed finish
Explanation: Glazed finish is used to give a very pleasing and shiny appearance to the surfaces. Hence, this type of surface finish is widely used for decorative works.
10. Solid concrete blocks are obtained from lightweight aggregates while hollow concrete blocks are obtained from heavy aggregates.
a) True
b) False
Explanation: Concrete masonry uses two types of cement concrete blocks for the construction of walls – hollow concrete block and solid concrete block. Solid concrete blocks are obtained from heavy aggregates while hollow concrete blocks are obtained from lightweight aggregates.