If 20 kg of coarse aggregate is sieved through 80 mm, 40 mm, 20 mm, 10 mm, 4.75 mm, 2.36 mm, 1.18 mm, 600 micron, 300 micron and 150 micron standard sieves and the weights retained are 0 kg, 2 kg, 8 kg, 6 kg, 4 kg respectively, the fineness modulus of the aggregate, is
7.30
7.35
7.40
7.45
Correct Answer :
C. 7.40
Related Questions
To hydrate 500kg of cement full water needed, is
100 kg
110 kg
120 kg
130 kg
The property of fresh concrete, in which the water in the mix tends to rise to the surface while placing and compacting, is called
Segregation
Bleeding
Bulking
Creep
As compared to ordinary Portland cement, high alumina cement has
Higher initial setting time but lower final setting time
Lower initial setting time but higher final setting time
Higher initial and final setting times
Lower initial and final setting times
The effect of adding calcium chloride in concrete is (i) To increase shrinkage (ii) To decrease shrinkage (iii) To increase setting time (iv) To decrease setting time The correct answer is
(i) and (iii)
(i) and (iv)
(ii) and (iii)
(ii) and (iv)
Workability of concrete for a given water content is good if the aggregates, are
Rounded aggregate
Irregular aggregate
Angular aggregate
Flaky aggregates
In working stress design, permissible bond stress in the case of deformed bars is more than that in plain bars by
10 %
20 %
30 %
40 %
Non-uniform compaction may cause the concrete
Porous
Non-homogeneous
Reduced strength
All the above
To obtain a very high strength concrete, use very fine grained
Granite
Magnetite
Barite
Volcanic scoria
If a beam fails in bond, then its bond strength can be increased most economically by
Increasing the depth of beam
Using thinner bars but more in number
Using thicker bars but less in number
Providing vertical stirrups
The relation between modulus of rupture fcr, splitting strength fcs and direct tensile strength fcl is given by
fcr - fcs = fcl
fcr > fcs > fcl
fcr < fcs < fcl
fcs > fcr > fcl
According to Whitney's theory, ultimate strain of concrete is assumed to be
0.03 %
0.1 %
0.3 %
3 %
Pick up the correct statement from the following:
An increase in water content must be accompanied by an increase in cement content
Angular and rough aggregates reduce the workability of the concrete
The slump of the concrete mix decreases due to an increase in temperature
All the above
In counterfort type retaining walls (i) The vertical slab is designed as a continuous slab (ii) The heel slab is designed as a continuous slab (iii) The vertical slab is designed as a cantilever (iv) The heel slab is designed as a cantilever The correct answer is
(i) and (ii)
(i)and(iv)
(ii) and (iii)
(iii) and (iv)
Concrete gains strength due to
Chemical reaction of cement with sand and coarse aggregates
Evaporation of water from concrete
Hydration of cement
All the above
Inert material of a cement concrete mix, is
Water
Cement
Aggregate
None of these
The recommended value of modular ratio for reinforced brick work is
18
30
40
58
High carbon content in the steel causes
Decrease in tensile strength but increase in ductility
Increase in tensile strength but decrease in ductility
Decrease in both tensile strength and ductility
Increase in both tensile strength and ductility
Pre-stress loss due to friction occurs
Only in post-tensioned beams
Only in pre-tensioned beams
In both post-tensioned and pre-tensioned beams
None of the above
Pozzolana cement is used with confidence for construction of
Dams
Massive foundations
R.C.C. structures
All the above
Tricalcium aluminate (C3A)
Reacts fast with water
Generates less heat of hydration
Causes initial setting and early strength of cement
Does not contribute to develop ultimate strength
Select the correct statement
Elastic modulus of high tensile steel is nearly the same as that of mild steel
Elastic modulus of high tensile steel is more than that of mild steel
Carbon percentage in high carbon steel is less than that in mild steel
High tensile steel is cheaper than mild steel
If the size of panel in a flat slab is 6 m × 6 m, then as per Indian Standard Code, the widths of column strip and middle strip are
3.0 m and 1.5 m
1.5 m and 3.0 m
3.0 m and 3.0 m
1.5 m and 1.5 m
Permissible compressive strength of M 200 concrete grade is
100 kg/cm2
150 kg/cm2
200 kg/cm2
250 kg/cm2
Workability improved by adding
Fly ash
Hydrated lime
Calcium chloride
All the above
According to Water-Cement Ratio Law, the strength of workable plastic concrete
Depends upon the amount of water used in the mix
Does not depend upon the quality of cement mixed with aggregates
Does not depend upon the quantity of cement mixed with aggregates
All the above
Curing of pavements, floors, roofs and slabs, is done by
Membrane method
Ponding method
Covering surface with bags
Sprinkling water method
The diameter of ties in a column should be
More than or equal to one fourth of diameter of main bar
More than or equal to 5 mm
More than 5 mm but less than one-fourth of diameter of main bar
More than 5 mm and also more than one-fourth of diameter of main bar
For a cantilever of effective depth of 0.5 m, the maximum span to satisfy vertical deflection limit is
3.5 m
4 m
4.5 m
5 m
For ensuring quality of concrete, use
Single sized aggregates
Two sized aggregate
Graded aggregates
Coarse aggregates
The rock which is not calcareous, is:
Lime stone
Chalk
Laterite
None of these