To reduce the tensile stresses likely to be developed due to evaporation of water
To minimise the change in the dimensions of the slab
To minimise the necessary cracking
All the above
D. All the above
0.207 l
0.25 l
0.293 l
0.333 l
P = [(Z - X)/(Z - Y)] × 100
P = [(X - Z)/(Z - Y)] × 100
P = [(X - Z)/(Z + Y)] × 100
P = [(Z + X)/(Z - Y)] × 100
Sand obtained from pits, is washed to remove clay and silt
Sand obtained from flooded pits, need not be washed before use
The chloride in sea shore sand and shingle may cause corrosion of reinforcement if the concrete is porous
All the above
Has strength less than 10% to 15%
Has more resistance to weathering
Is more plastic and workable
Is free from segregation and bleeding
Rounded aggregate
Irregular aggregate
Angular aggregate
Flaky aggregates
Fineness test
Consistency test
Test for setting time
Test for tensile strength
Less
More
Equal
None of the above
100 kg
110 kg
120 kg
130 kg
2.5 cm
5.0 cm
7.5 cm
10 cm
Voids in coarse aggregates are filled by fine aggregates
Voids in fine aggregates are filled by the cement paste
Volume of fine aggregates is equal to total voids in coarse aggregates plus 10% extra
All the above
Ferrous sulphate
Potassium chloride
Ammonia
Nitric acid
Wetter mix
Larger proportion of maximum size aggregate
Coarser grading
All the above
To reduce the tensile stresses likely to be developed due to evaporation of water
To minimise the change in the dimensions of the slab
To minimise the necessary cracking
All the above
(i) and (ii)
(i)and(iv)
(ii) and (iii)
(iii) and (iv)
Internal moisture conditions on hydration continue till complete strength is gained
Concrete specimens may be tested at any temperature
Concrete specimens need be of same age
Concrete specimens need be of same size
Dry
Earth moist
Semi-plastic
Plastic
Aggregate cement ratio
Time of transit
Grading of the aggregate
All of above
100 kg/cm2
150 kg/cm2
200 kg/cm2
250 kg/cm2
Mixing of different sizes of sand particles
Mixing of lime with sand
Maximum water with sand
Swelling of sand when wetted
1 : 3 : 6 mix
1 : 1 : 2 mix
1 : 2 : 4 mix
1 : 1.5 : 3 mix
Course
Medium
Medium to fine
Fine
50 mm
75 mm
100 mm
120 mm
Rounded
Elongated
Angular
All of the above
Workability of concrete
Strength of concrete
Durability of concrete
All the above
Tonnes/cubic metre
kg/cubic metre
kg/litre
g/cm3
0.37 fy
0.57 fy
0.67 fy
0.87 fy
3
4
5
7
Tricalcium silicate (C3S) hydrates rapidly
Tricalcium silicate (C3S) generates more heat of hydration
Tricalcium silicate (C3S) develops early strength
Tricalcium silicate (C3S) has more resistance to sulphate attack
Made with cement concrete
Thick and reinforced
Thin and heavily reinforced
Thick and heavily reinforced
M 100
M 200
M 300
M 500