MCQ
22281. The average out-turn of first class bricks in kiln burning is-
50 to 60%
60 to 70%
70 to 80%
80 to 90%
22282. For the construction of retaining walls, a------stone must be used.
soft
hard
heavy
light
22283. The size of mould for bricks should be---- the specified size of the bricks.
equal to
double
smaller than
larger than
22284. The fuel generally used for burning limestone is
coalur
firewood
charcoal
any one of these
22285. The percentage of alumina in a good brick clay should vary from-
20 to 30%
30 to 40%
40 to 50%
50 to 60%
22286. The frog of a brick is normally made on its-
longer face
bottom face
shorter face
top face
22287. The amount of gypsum usually added in the manufacture of cement is-
0.5 to 1%
3 to 5%
1 to 3%
0.1 to 0.5%
22288. The compressive strength of paving bricks should not be less than-
20 MN/m²
30 MN/m²
40 MN/m²
50 MN/m²
22289. The main constituent of Portland cement is-
lime
iron oxide
alumina
alkalies
22290. The average out-turn of first class bricks in clamp burning is about-
50%
60%
70%
80%
22291. The normal consistency of Portland cement is about-
10%
15%
20%
25%
22292. The cementing property in cement is mainly due to---
lime
silica
iron oxide
alumina
22293. The percentage of the slag component of Portland-slag cement varies from-
10 to 40%
70 to 80%
40 to 70%
80 to 90%
22294. The final setting time of ordinary cement should not be more than-
2 hours,
4 hours
4 hours
10 hours
22295. The natural drying of bricks is also called back drying.
true
false
22296. The burning of bricks in kilns is completed within-----hours.
12
24
48
96
22297. For one cubic metre of brick masonry, the number of bricks required is-
400
450
500
550
22298. The compressive strength of perforated bricks should not be less than-
4 MN/m²
5 MN/m²
6 MN/m²
7 MN/m²
22299. The silica in Portland cement should be
10 to 20%
20 to 25%
25 to 40%
40 to 60%
22300. The commonly used lime in white washing is---
quick lime
fat lime
lean lime
hydraulic lime