MCQ
20821. 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
20822. 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
20823. Which of the following is the purest form of iron? [BB-20]
Cast iron
Wrought iron
Mild steel
High carbon steel
ব্যাখ্যা: 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.
20824. What is the main compound of typical Portland Cement- [PBRLP-21]
CaO
SiO₂
Al₂O3
Fe,O3
20825. A good quality of stone absorbs water less than------[BPSC-22]
5%
10%
15%
20%
ব্যাখ্যা: 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.
20826. Inner part of a timber log surrounding the pith, is called- [PBRLP-21]
Sapwood
Cambium layer
Heartwood
None of the above
20827. A first class brick when immersed in cold water for 24 hours should not absorb water more than- [BPSC-22]
10%
20%
15%
25%
ব্যাখ্যা: 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%.
20828. The diameter of the needle of Vicat apparatus for measuring in initial setting is- [PBRLP-21]
0.5mm
1.0mm
1.10mm
1.50mm
20829. The initial setting time of rapid hardening cement should not be less than--
30 min
4 hours
1 hour
10 hours
20830. The compressive strength of ordinary cement is less than its tensile strength
right
wrong
20831. 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
20832. Initial setting time (minimum) of ordinary port land cement is- [BPSC-22]
60 minutes
45 minutes
30 minutes
20 minutes
ব্যাখ্যা: ব্যাখ্যা: Initial setting time (minimum) of ordinary portland cement is 30 minutes and final setting time 10 hours.
20833. The normal consistency of Portland cement is about-
10%
15%
20%
25%
20834. ইটের Herring-bone bond গাঁথুনি কোন কাজে ব্যবহৃত হয়?
Brick paving
Very thick wall
Partition walls
Footing foundation
20835. যদি বালুর FM ৩.০ হয় তবে উক্ত বালুকে বলা হয়-
very fine sand
fine sand
medium sand
flaky
20836. In a mortar, the binding material is-[PBRLP-21]
Cement
Sand
Course aggregate
Water
20837. The final setting time of ordinary cement should not be more than-
2 hours,
4 hours
4 hours
10 hours
20838. The moisture content in timber for framework should not exceed-
5%
10%
15%
20%
20839. In brick field, pugmill is used for- [BPSC-22]
preparation of clay
drying of bricks
burning of bricks
moulding of bricks
ব্যাখ্যা: 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.
20840. The main purpose of timber seasoning is-[BPSC-22]
to make timber cocter
to made timber fire resistant
to remove moisture at uniform rate
None of the above
ব্যাখ্যা: 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.