CONCRETE 2

Question 1

CLASSIFICATION ACCORDING TO DESIGN OF CONCRETE

Answer 1

1. Plain cement concrete.
2. Reinforced cement concrete(RCC).
3. Pre-stressed cement concrete(PCC)

Question 2

The cement concrete in which no reinforcement is provided.
This type of concrete is strong in taking compressive
stresses but weak in taking tensile stresses.
is commonly used in for foundation work and flooring of buildings.

Answer 2

plain cement concrete

Question 3

embedded for taking tensile stress
e the steel reinforcement is to be
used generally in the form of round bars,6mm to 32mm dia
commonly used for construction of slabs, beams, columns, foundation,
precast concrete.

Answer 3

reinforced cement concrete

Question 4

s. Usual proportions of ingredients
in a reinforced concrete

Answer 4

1 part of cement:1-2parts of sand:2-4parts of crushed stones
or gravel.

Question 5

high compressive stresses are artificially induced before their actual use
e high compressive stresses are induced by pre-tensioning the reinforcement before placing the concrete, and the reinforcement is released when final setting of the concrete
take place.
can take up high tensile and compressive stresses without development of cracks. The quantity of reinforcement can be considerably reduced by using this concrete.

Answer 5

pre-stressed cement concrete

Question 6

according to purpose of concrete

Answer 6

vacuum concrete
air-entrained concrete
light weight concrete

Question 7

the cement concrete from which
entrained air and excess water is
removed after placing it, by suction
with the help of vacuum pump
e the excess water which is
added to increase workability but
not required for the hydration of
cement of concrete is removed by
forming vacuum chamber.

Answer 7

vacuum concrete

Question 8

concrete prepared by mixing
aluminum in it
bubbles of
hydrogen gas are liberated which
forms cell and make the concrete
cellular.
used for lining walls and roofs for
heat and sound insulation purpose.

Answer 8

air entertained concrete

Question 9

prepared by using coke
breeze, cinder or slag as coarse
aggregate
is light in
weight and posses heat insulating
properties.
used in making precast structural units for
partition and wall lining

Answer 9

light weight concrete

Question 10

CLASS AA

Answer 10

1: 1 1/2 : 3
concrete under water, retaining walls

Question 11

CLASS A

Answer 11

1 : 2 : 4
footings, column, beams, RC slabs

Question 12

CLASS B

Answer 12

1 : 2 1/2 : 5
slab on-fill, non bearing wall

Question 13

CLASS C

Answer 13

1 : 3 : 6
concrete plant box, etc