If the slump of a concrete mix is 60 mm, its workability is
Very low
Low
Medium
High
Correct Answer :
C. Medium
Related Questions
Pick up the incorrect statement from the following:
A rich mix of concrete possesses higher strength than that a lean mix of desired workability with excessive quantity of water
The strength of concrete decreases as the water cement ratio increases
Good compaction by mechanical vibrations, increases the strength of concrete
None of these
Pick up the correct statement from the following:
High percentage of C3S and low percentage of C2S cause rapid hardening
High percentage of C3S and low percentage of C2S make the cement less resistive to chemical attack
Low percentage of C3S and high percentage of C2S contribute to slow hardening
All the above
Pick up the incorrect statement from the following. While performing preliminary test on concrete
Proportions of the material and water should be the same as to be used at the work site
Cement should be mixed by hand in order to maintain uniformity
Concrete mix should be stored in air-tight containers
Concrete ingredients should be kept at a temperature of 37° ± 2°C
For the construction of the retaining structures, the type of concrete mix to be used, is
1 : 3 : 6
1 : 2 : 4
1 : 1 ½ : 3
1 : 4 : 8
If the depth of actual neutral axis in a beam is more than the depth of critical neutral axis, then the beam is called
Balanced beam
Under-reinforced beam
Over-reinforced beam
None of the above
The type of aggregates not suitable for high strength concrete and for pavements subjected to tension, is
Rounded aggregate
Irregular aggregate
Angular aggregate
Flaky aggregate
The process of hardening the concrete by keeping its surface moist is known
Placing
Wetting
Curing
Compacting
Concrete containing
Siliceous aggregates, has higher co-efficient of expansion
Igneous aggregates, has intermediate coefficient of expansion
Lime stones, has lowest co-efficient of expansion
All the above
If aggregates completely pass through a sieve of size 75 mm and are retained on a sieve of size 60 mm, the particular aggregate will be flaky if its minimum dimension is less than
20.5 mm
30.5 mm
40.5 mm
50.5 mm
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
Which of the following has high tensile strength?
Plain hot rolled wires
Cold drawn wires
Heat treated rolled wires
All have same tensile strength
The load factors for live load and dead load are taken respectively as
1.5 and 2.2
2.2 and 1.5
1.5 and 1.5
2.2 and 2.2
Maximum quantity of water needed per 50 kg of cement for M 15 grade of concrete is
28 liters
30 liters
32 liters
34 liters
I.S. Sieve Nos. 10 mm and 4.75 mm are generally used for grading of
Coarse aggregates
Fine aggregates
Neither (a) nor (b)
Both (a) and (b)
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
According to Whitney's theory, depth of stress block for a balanced section of a concrete beam is limited to
0.43 d
0.537 d
0.68 d
0.85 d Where d is effective depth of beam
Pick up the correct statement from the following:
Sand stones may be divided into calcareous, siliceous and ferruginous sand stones
Concrete using sand stones, cracks due to excessive shrinkage
Broken bricks produce a concrete having good fire resisting qualities
All the above
The main reinforcement in the toe of a T-shaped R C. retaining wall is provided on
(i) Top face parallel to the wall
(ii) Top face perpendicular to the wall
(iii) Bottom face parallel to the wall
(iv) Bottom face perpendicular to the wall The correct answer is
Only (ii) is correct
(i) and (ii) are correct
(iii) and (iv) are correct
Only (iv) is correct
A T-shaped retaining wall mainly consists of
One cantilever
Two cantilevers
Three cantilevers
Four cantilevers
The aggregate containing moisture in pores and having its surface dry, is known as
Moist aggregates
Very dry aggregates
Dry aggregates
Saturated surface dry aggregate
Modulus of elasticity of steel as per IS: 4561978 shall be taken as
20 kN/cm²
200 kN/cm²
200 kN/mm²
2 × 106 N/cm²
For a concrete mix 1:3:6 and water cement ratio 0.6 both by weight, the quantity of water required per bag, is
10 kg
12 kg
14 kg
16 kg
Pick up the correct statement from the following:
Cement should be mixed for at least one minute
10% of water is placed in the rotating drum before adding dry material
10% of water is added after placing the other ingredients in the drum
All the above
Gypsum is added for
Colour
Strength
Controlling setting time
None of these
For given water content, workability decreases if the concrete aggregates contain an excess of
Thin particles
Flat particles
Elongated particles
All the above
Transport of concrete by pumps, is done for a distance of
100 m
200 m
300 m
400 m
Higher workability of concrete is required if the structure is
Made with cement concrete
Thick and reinforced
Thin and heavily reinforced
Thick and heavily reinforced
The preliminary test is repeated if the difference of compressive strength of three test specimens, exceeds
5 kg/cm2
8 kg/cm2
10 kg/cm2
15 kg/cm2
The centroid of compressive force, from the extreme compression fiber, in limit state design lies at a distance of (Where xu is the depth of neutral axis at the limit state of collapse)
0.367 xu
0.416 xu
0.446 xu
0.573 xu
Permissible compressive strength of M 150 concrete grade is
100 kg/cm2
150 kg/cm2
200 kg/cm2
250 kg/cm2