Basic Building Construction Questions and Answers on “Types of Upper Floors – 2”.
1. In simple reinforced cement concrete slab flooring, it is important to provide reinforcement in both the directions when the length of the room is _________ times its width.
a) 0.5
b) 1
c) 1.5
d) 2
Answer: c
Clarification: In simple reinforced cement concrete slab flooring, it is important to provide reinforcement in both the directions when the length of the room is 1.5 times its width. This is because in this case, the slab bends in both the directions and such a slab is called two-way reinforced slab.
2. Which grade of cement concrete is used in the construction of simple R.C.C. floors?
a) M15
b) M10
c) M30
d) M20
Answer: d
Clarification: In simple R.C.C. floors, generally cement concrete of M20 mix is used. After pouring of the concrete, it is well-compacted and the slab is properly cured. Shuttering can be removed only when the concrete has fully been set.
3. Which type of bricks should be used in the construction of reinforced brick flooring?
a) First class bricks
b) Second class bricks
c) Third class bricks
d) Fourth class bricks
Answer: a
Clarification: Bricks are classified into 3 types – first class bricks, second class bricks and third class bricks. Only first class bricks should be used in the construction of reinforced brick flooring. The size of the first class bricks is 19 cm x 9 cm x 9 cm.
4. The beams used in beam-slab flooring are known as _________
a) B-beams
b) R-beams
c) K-beams
d) T-beams
Answer: d
Clarification: The beams used in beam-slab flooring are known as T-beams. In this type of flooring, the floor is comprised of R.C.C. beams and slabs cast monolithically. Beams serve as intermediate supports to the slab that is continuous over these beams.
5. Ribbed floors are also known as __________
a) Filler joists floors
b) R.C.C. floors
c) Hollow-tiled floors
d) Solid-tiled floors
Answer: c
Clarification: Ribbed floors are also known as hollow-tiled floors. In this type of flooring, hollow tiles replace the lower part of the slab since concrete cannot bear the tension caused in the lower part of the slab. The use of hollow tiles also reduces the weight of the slab.
6. The clearing spacing of the ribs in ribbed flooring should not exceed ________
a) 10 cm
b) 20 cm
c) 40 cm
d) 50 cm
Answer: d
Clarification: In ribbed flooring, the ribs are closely spaced and the clearing spacing of the ribs should not exceed 50 cm. It depends on the size of the hollow blocks available.
7. In ribbed flooring, lateral ribs having the same width as that of longitudinal ribs are provided if the span exceeds ________
a) 1 cm
b) 1 m
c) 3 cm
d) 3 m
Answer: d
Clarification: In ribbed flooring, lateral ribs having the same width as that of longitudinal ribs are provided if the span exceeds 3 m. These are provided at intervals between 1-3 m.
8. In ribbed flooring, the depth of the rib is at least _________ with the free support.
a) L/10
b) L/20
c) L/25
d) L/30