MCQ
20881.
The moisture content in timber for framework should not exceed-
5%
10%
15%
20%
20882.
The cementing property in cement is mainly due to---
lime
silica
iron oxide
alumina
20883.
ইটের Herring-bone bond গাঁথুনি কোন কাজে ব্যবহৃত হয়?
Brick paving
Very thick wall
Partition walls
Footing foundation
20884.
Lime occurs in a free state in nature.
True
False
20885.
The normal consistency of Portland cement is about-
10%
15%
20%
25%
20886.
The main constituent of Portland cement is-
lime
iron oxide
alumina
alkalies
20887.
The compressive strength of paving bricks should not be less than-
20 MN/m²
30 MN/m²
40 MN/m²
50 MN/m²
20888.
The percentage of the slag component of Portland-slag cement varies from-
10 to 40%
70 to 80%
40 to 70%
80 to 90%
20889.
The time required for seasoning of timber in kiln seasoning is-
2 to 5 days
5 to 10 days
10 to 20 days
20 to 40 days
20890.
The average out-turn of first class bricks in kiln burning is-
50 to 60%
60 to 70%
70 to 80%
80 to 90%
20891.
The burning of bricks in kilns is completed within-----hours.
12
24
48
96
20892.
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%
20893.
For one cubic metre of brick masonry, the number of bricks required is-
400
450
500
550
ব্যাখ্যা: [Note: মেট্রিক ইট 500টি লাগে।
20894.
The compressive strength of perforated bricks should not be less than-
4 MN/m²
5 MN/m²
6 MN/m²
7 MN/m²
20895.
The silica in Portland cement should be
10 to 20%
20 to 25%
25 to 40%
40 to 60%
ব্যাখ্যা: ব্যাখ্যা: ১। ক্যালসিয়াম অক্সাইড (CaO)..........63%
২। ম্যাগনেশিয়াম অক্সাইড (MgO)..........2%
৩। সিলিকা (SiO₂)..........22%
৪। অ্যালুমিনা (Al2O3)..........7%
৫। আয়রন অক্সাইড (Fe2O3)..........3%
৬। সালফার ট্রাই-অক্সাইড (SO3).........2%
৭। ক্ষারকীয় পদার্থ...........1%
........ মোট 100%
20896.
The commonly used lime in white washing is---
quick lime
fat lime
lean lime
hydraulic lime
20897.
The initial setting time of rapid hardening cement should not be less than--
30 min
4 hours
1 hour
10 hours
20898.
The final setting time of ordinary cement should not be more than-
2 hours,
4 hours
4 hours
10 hours
20899.
The compressive strength of ordinary cement is less than its tensile strength
right
wrong
20900.
The fuel generally used for burning limestone is
coalur
firewood
charcoal
any one of these