Rapid hardening cement contains
Tri-calcium silicate
Tri-calcium aluminate
Tetra-calcium alumino-ferrite
Di-calcium silicate
Correct Answer :
A. Tri-calcium silicate
Related Questions
The slag which floats on the surface of the molten iron generally contains
Lime (CaO) 45%
Silica (SiO2) 35%
Alumina (Al2O3) 12% and MgO, CaSO4, KMnO2 and FeO 8%
All the above
In a rock calcium carbonate predominates. State whether it is:
Siliceous rock
Argillaceous rock
Calcareous rock
None of these
Mastic asphalt is
Acid resisting material
Non-corrosive material
Corrosive material
Heating-resisting material
Mastic asphalt is
Water proof
Fire proof
Elastic
All the above
A first class brick when immersed in cold water for 24 hours should not absorb water more than
15 %
20 %
22 %
25 %
Quick setting cement is produced by adding
Less amount of gypsum in very fine powdered form
More amount of gypsum in very fine powdered form
Aluminium sulphate in very fine powdered form
Pozzolana in very fine powdered form
The size of modular bricks, is
10 × 10 × 9 cm
19 × 9 × 9 cm
22.5 × 10 × 8.5 cm
22.5 × 8.0 × 9 cm
The rocks which are formed due to cooling of magma at a relatively shallow depth from the earth's surface are called
Plutonic rocks
Hypabyssal rocks
Volcanic rocks
Igneous rocks
The wedging is adopted for quarrying costly stratified rock such as
Laterite
Marble
Limestone
All the above
Excess of silica in brick earth results in
Cracking and warping of bricks
Loss of cohesion
Enhancing the impermeability of bricks
None of the above
Elastomers can extend upto
Five times their original dimensions
Seven times their original dimensions
Ten times their original dimensions
Three times their original dimensions
Which of the following trees yields hard wood?
Deodar
Chir
Shishum
Pine
Cast steel is manufactured by
Cementation process
Crucible process
Bessemer process
Open hearth process
The most important tool in brick laying for lifting and spreading mortar and for forming joints is
Trowel
Square
Bolster
Scutch
Asbestos cement
Is brittle
Warps due to changes in humidity
Strength is lowered when saturated by water
All of the above
Pick up the correct statement from the following:
The baked earth is called terra-cotta
The articles prepared from clay which is burnt at low temperature and cooled down slowly, are called earthen-ware
The articles prepared from refractory clays which as mixed with stone and crushed pottery, are called stone ware
All the above
Which of the following ingredients of the brick earth enables the brick to retain its shape?
Alumina
Silica
Iron
Magnesia
Pick up the correct statement from the following: Method of sawing timber
Tangentially to annual rings, is known as tangential method
In four quarters such that each board cuts annual rings at angles not less than 45°, is known as quarter sawing method
Cut out of quarter logs, parallel to the medullary rays and perpendicular to annual rings, is known as radial sawing
All the above
Lime putty
Is made from hydraulic lime
Is made by adding lime to water
Can be used only upto three days
All of above
Clay and silt content in a good brick earth must be at least
50 %
40 %
30 %
25 %
The initial setting time of hydraulic lime, is
30 minutes
60 minutes
90 minutes
120 minutes
The age of a tree can be known by examining
Cambium layer
Annular rings
Medullary rays
Heart wood
The operation of removal of impurities or clay adhering to iron ores, is known as
Dressing
Calcination
Roasting
Smelting
Which of the following is a rock?
Quartz
Mica
Gypsum
None of the above
A piece of timber whose thickness and width are respectively 5 cm and 10 cm is called
Slate
Plank
Board
Strip
Pick up the correct characteristic of Pyroxene from the following:
It forms octagonal crystals
It converts to chlorine by hydration
Its density is 2.3 to 3.6 g/cm2
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)
The specific gravity of marble, is
2.50
2.60
2.66
2.72
The cast iron when heated to red heat with powdered red haematite in an oven for increasing its toughness, is converted to
Grey cast iron
White cast iron
Mottled cast iron
Toughed cast iron
The colour of statuary marble used for sculptor's work, is
Red
Blue
White
Green