MCQ
20821. Initial setting time (minimum) of ordinary port land cement is- [BPSC-22]
ব্যাখ্যা: Initial setting time (minimum) of ordinary portland cement is 30 minutes and final setting time 10 hours.
60 minutes
45 minutes
30 minutes
20 minutes
20822. যদি বালুর FM ৩.০ হয় তবে উক্ত বালুকে বলা হয়-
very fine sand
fine sand
medium sand
flaky
20823. The diameter of the needle of Vicat apparatus for measuring in initial setting is- [PBRLP-21]
0.5mm
1.0mm
1.10mm
1.50mm
20824. The initial setting time of rapid hardening cement should not be less than--
30 min
4 hours
1 hour
10 hours
20825. Inner part of a timber log surrounding the pith, is called- [PBRLP-21]
Sapwood
Cambium layer
Heartwood
None of the above
20826. What is the main compound of typical Portland Cement- [PBRLP-21]
CaO
SiO₂
Al₂O3
Fe,O3
20827. The normal consistency of Portland cement is about-
10%
15%
20%
25%
20828. The final setting time of ordinary cement should not be more than-
2 hours,
4 hours
4 hours
10 hours
20829. A first class brick when immersed in cold water for 24 hours should not absorb water more than- [BPSC-22]
ব্যাখ্যা: A first class brick when immersed in cold 11 water for 24 hours, it absorb 1/5 to 1/7 (15% to 20%).
It should not absorb water more than 20%.
10%
20%
15%
25%
20830. Which of the following is the purest form of iron? [BB-20]
ব্যাখ্যা: Wrought iron is the purest from of iron. It contains 0.12 to 0.25% carbon and is thus the purest from of iron.
Cast iron
Wrought iron
Mild steel
High carbon steel
20831. What happens when fineness of cement is increased- [PBRLP-21]
It decreases the rate of hydration
It has no-impact on rate of hydration
It increases the rate of hydration
None of the above
20832. The main purpose of timber seasoning is-[BPSC-22]
ব্যাখ্যা: Seasoning of timber is the process by which moisture content in the timber is reduced to required level. By reducing moisture content, the strength, elasticity and durability properties are developed.
to make timber cocter
to made timber fire resistant
to remove moisture at uniform rate
None of the above
20833. A good quality of stone absorbs water less than------[BPSC-22]
ব্যাখ্যা: A good building stone should be less porous. It should not absorb more than 5% of water. Any stone absorbing 10% of water should be rejected.
5%
10%
15%
20%
20834. In brick field, pugmill is used for- [BPSC-22]
ব্যাখ্যা: A pugmill or pug mill is a machine in which clay or other materials are mixed into a plastic state. A pugmill
may be a fast continous mixer.
preparation of clay
drying of bricks
burning of bricks
moulding of bricks
20835. ইটের Herring-bone bond গাঁথুনি কোন কাজে ব্যবহৃত হয়?
Brick paving
Very thick wall
Partition walls
Footing foundation
20836. If two types of sand having FM 2.5 and 2.25 respectively and mix together as same ratio what will be the combined FM? [MOD-20]
2.65
2.37
4.75
4.5
20837. The compressive strength of ordinary cement is less than its tensile strength
right
wrong
20838. In a mortar, the binding material is-[PBRLP-21]
Cement
Sand
Course aggregate
Water
20839. 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
20840. The moisture content in timber for framework should not exceed-
5%
10%
15%
20%