The most commonly used retarder in cement is
Gypsum
Calcium chloride
Calcium carbonate
None of the above
Correct Answer :
A. Gypsum
Related Questions
Gypsum consists of
H₂S and CO₂
CaSO4 and H₂O
Lime and H₂O
CO₂ and calcium
The pressure acting on the stones in stone masonry construction should be
Along the direction of bedding planes
At 45° to the direction of bedding planes
At 60° to the direction of bedding planes
Perpendicular to the direction of bedding planes
Pick up the correct statement from the following:
Hornblende mineral is brittle
Muscovite is also known as white mica and potash mica
Biotite is also known as black-mica
All the above
If the furnace is provided with insufficient fuel at low temperatures, the type of pig iron produced, is called
Bessemer pig
Grey or foundry pig
White or forge pig
Mottled pig
In the cement the compound quickest to react with water, is
Tri-calcium aluminate
Tetra-calcium alumino-ferrite
Tri-calcium silicate
Di-calcium silicate
Ultimate strength to cement is provided by
Tri-calcium silicate
Di-calcium silicate
Tri-calcium aluminate
Tetra calcium alumino ferrite
Pick up the correct statement from the following:
Bull's trench kiln a trench excavated in ground
Hoffman's kiln is constructed over ground
Tunnel Kiln is constructed as a tunnel
All the above
The commonly used lime in white washing, is
White lime
Fat lime
Hydraulic lime
Quick lime
Teak wood is suitable for
Sports articles
Furnitures
Railway sleepers
All the above
Blister steel
Is obtained by cementation process
Is full of fissures and cavities
Can be easily welded
All the above
Strength of cement concrete primarily depends upon
Quality of water
Quantity of aggregate
Quantity of cement
Water-cement ratio
A first class brick when immersed in cold water for 24 hours should not absorb water more than
15 %
20 %
22 %
25 %
Wrought iron is used for
Structural works in beams
Small sized water pipes
Columns and struts
None to these
The rocks which are formed due to cooling of magma at a considerable depth from earth's surface are called
Plutonic rocks
Hypabyssal rocks
Volcanic rocks
Igneous rocks
Granite is not suitable for ordinary building purpose because
It cannot be polished
It is not a fire proof material
It is costly
It has less crushing strength
For one cubic metre of brick masonry, number of bricks required, is
400
425
450
500
Acrylic is the name of
Cellulose resin
Alkyd resin
Methyl methacrylate
Cumarone-indene
The plywood
Has good strength along the panel only
Can be spilt in the plane of the panel
Has greater impact resistance to blows than ordinary wood
Cannot be bent more easily than ordinary wood of same thickness
Sandstone is a (i) Sedimentary rock (ii) Aqueous rock (iii) Siliceous rock The correct answer is
Only (i)
Both (i) and (ii)
Both (i) and (iii)
All (i), (ii) and (iii)
Plastic bitumen is generally used for
Road pavements
Expansion joints
Crack fillings
None to these
Pick up the correct statement regarding low heat cement from the following:
It possesses less compressive strength
Its initial setting time is about one hour
Its final setting time is about 10 hours
All the above
Proper amount of entrained air in concrete results in (i) Better workability (ii) Better resistance to freezing and thawing (iii) Lesser workability (iv) Less resistance to freezing and thawing The correct answer is
(i) and (ii)
(i) and (iv)
(ii) and (iii)
(iii) and (iv)
Commonly used thinner in
Lacquer paints, is alcohol
Cellulose paints is ethyl acetate
Oil paints, is naphtha
All the above
Asbestos is
Corrugated sheet used for roofing
An incombustible fire proof material
An organic substance
All the above
Crushing strength of a good building stone should be more than
50 MPa
100 MPa
150 MPa
200 MPa
A 1st class brick immersed in water for 24 hours, should not absorb water (by weight) more than
10 %
15 %
20 %
25 %
Three basic raw materials which are needed in large quantities for production of steel are
Iron ore, coal and sulphur
Iron ore, carbon and sulphur
Iron ore, coal and lime stone
Iron ore, carbon and lime stone
Which of the following pairs gives a correct combination of the useful and harmful constituents respectively of a good brick earth?
Lime stone and alumina
Silica and alkalies
Alumina and iron
Alkalies and magnesium
The pigment used in paints for corrosive resistance, is
White lead
Ferrous oxide
Zinc white
Red lead
Quick lime is (i) Slow in setting (ii) Rapid in slacking (iii) Good in strength The correct answer is
Only (i)
Only (ii)
Both (i) and (ii)
Both (ii) and (iii)