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
Correct Answer :
B. Bleeding
Related Questions
Segregation is responsible for
Honey-combed concrete
Porous layers in concrete
Surface scaling in concrete
All the above
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
Strength of concrete with passage of time
Increases
Decreases
Fluctuates
Remains constant
The entrained air in concrete
Increases workability
Decreases workability
Decreases resistance to weathering
Increases strength
The diameter of the Vicat plunger is 10 mm and its length varies from
20 mm to 30 mm
30 mm to 40 mm
40 mm to 50 mm
50 mm to 60 mm
To minimise the effect of differential settlement, the area of a footing should be designed for
Dead load only
Dead load + live load
Dead load + fraction of live load
Live load + fraction of dead load
Workability of concrete is inversely proportional to
Time of transit
Water-cement ratio
The air in the mix
Size of aggregate
In a pile of length l, the points of suspension from ends for lifting it are located at
0.207 l
0.25 l
0.293 l
0.333 l
Shrinkage of concrete depends upon
(i) Humidity of atmosphere
(ii) Passage of time
(iii) Stress The correct answer is
(i) and (ii)
(ii) and (iii)
Only (iii)
All (i), (ii) and (iii)
The compaction of concrete, improves
Density
Strength
Durability
All the above
Which of the following R.C. retaining walls is suitable for heights beyond 6 m?
L-shaped wall
T-shaped wall
Counterfort type
All of the above
Permissible compressive strength of M 200 concrete grade is
100 kg/cm2
150 kg/cm2
200 kg/cm2
250 kg/cm2
Permissible compressive strength of M 300 concrete grade is
100 kg/cm2
150 kg/cm2
200 kg/cm2
300 kg/cm2
Pick up the incorrect statement from the following:
The bottom and top ends of slump mould are parallel to each other
The axis of the mould is perpendicular to the end faces
The internal surface of the mould is kept clean and free from set cement
The mould is in the form of a frustum of hexagonal pyramid
Slump test of concrete is a measure of its
Consistency
Compressive strength
Tensile strength
Impact value
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
Too wet concrete may cause
Weakness of concrete
Excessive laitance
Segregation
All the above
On a grading curve, the gap grading is represented by
A horizontal line
A vertical line
N.W. inclined line
N.E. inclined line
Hardening of cement occurs at
Rapid rate during the first few days and afterwards it continues to increase at a decreased rate
Slow rate during the first few days and afterwards it continues to increase at a rapid rate
Uniform rate throughout its age
None of these
Pick up the incorrect statement from the following:
Admixtures accelerate hydration
Admixtures make concrete water proof
Admixtures make concrete acid proof
Admixtures give high strength
Sinking of an intermediate support of a continuous beam (i) Reduces the negative moment at support (ii) Increases the negative moment at support (iii) Reduces the positive moment at center of span (iv) Increases the positive moment at center of span The correct answer is
(i) and (iii)
(i) and (iv)
(ii) and (iii)
(ii) and (iv)
The type of aggregates of same nominal size, which contain less voids when compacted, are
Rounded spherical
Irregular
Flaky
None of these
Pick up the correct statement from the following:
Lime in excess, causes the cement to expand and disintegrate
Silica in excess, causes the cement to set slowly
Alumina in excess, reduces the strength of the cement
All the above
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
How long will it take for the concrete to achieve 100% of its strength?
7 days
14 days
21 days
28 days
The percentage of voids in cement is approximately
25 %
40 %
60 %
80 %
To hydrate 500kg of cement full water needed, is
100 kg
110 kg
120 kg
130 kg
Pick up the incorrect statement from the following:
The degree of grinding of cement, is called fineness
The process of changing cement paste into hard mass, is known as setting of cement
The phenomenon by virtue of which cement does not allow transmission of sound, is known as soundness of cement
The heat generated during chemical reaction of cement with water, is known as heat of hydration
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
Minimum pitch of transverse reinforcement in a column is
The least lateral dimension of the member
Sixteen times the smallest diameter of longitudinal reinforcement bar to be tied
Forty-eight times the diameter of transverse reinforcement
Lesser of the above three values