A concrete having a slump of 6.5 cm, is said to be
Dry
Earth moist
Semi-plastic
Plastic
Correct Answer :
D. Plastic
Related Questions
For an ordinary Portland cement
Residual does not exceed 10% when sieved through IS Sieve No. 9
Soundness varies from 5 to 10 mm
Initial setting time is not less than 30 minutes
Compressive stress after 7 days, is not less than 175 kg/cm2
The temperature reinforcement in the vertical slab of a T-shaped R.C. retaining wall is
Not needed
Provided equally on inner and front faces
Provided more on inner face than on front face
Provided more on front face than on inner face
Slump test of concrete is a measure of its
Consistency
Compressive strength
Tensile strength
Impact value
To obtain a very high strength concrete, use very fine grained
Granite
Magnetite
Barite
Volcanic scoria
A concrete using an air entrained cement
Has strength less than 10% to 15%
Has more resistance to weathering
Is more plastic and workable
Is free from segregation and bleeding
The main reinforcement in the heel of a T-shaped R.C. retaining wall is provided on
Top face perpendicular to wall
Bottom face perpendicular to wall
Both top and bottom faces perpendicular to wall
None of the above
The risk of segregation is more for
Wetter mix
Larger proportion of maximum size aggregate
Coarser grading
All the above
The percentage of reinforcement in case of slabs, when high strength deformed bars are used is not less than
0.15
0.12
0.30
1.00
Pick up the correct statement from the following:
Construction joints in columns are provided a few cm below the junction of beam
Construction joints in columns are provided at the bottom hunching
Construction joints in beams and slabs are provided within middle third
All the above
Pick up the correct statement from the following:
The concrete gains strength due to hydration of cement
The concrete does not set at freezing point
The strength of concrete increases with its age
All the above
High temperature
Increases the strength of concrete
Decreases the strength of concrete
Has no effect on the strength of concrete
None of these
Inert material of a cement concrete mix, is
Water
Cement
Aggregate
None of these
Permissible compressive strength of M 200 concrete grade is
100 kg/cm2
150 kg/cm2
200 kg/cm2
250 kg/cm2
Assertion A : The load factor for live load is greater than that for dead load. Reason R : The live loads are more uncertain than dead loads. Select your answer based on the coding system given below:
Both A and R is true and R is the correct explanation of A
Both A and R is true but R is not the correct explanation of A
A is true but R is false
A is false but R is true
The strength and quality of concrete, depend upon:
Grading of aggregates
Surface area of aggregates
Shape of aggregates
All the above
For the construction of thin R.C.C. structures, the type of cement to be avoided, is
Ordinary Portland cement
Rapid hardening cement
Low heat cement
Blast furnace slag cement
Bulking of sand is maximum if moisture content is about
2 %
4 %
6 %
10 %
An aggregate which passes through 25 mm I.S. sieve and is retained on 20 mm sieve, is said to be flaky if its least dimension is less than
22.5 mm
18.5 mm
16.5 mm
13.5 mm
Maximum percentage reinforcement in case of slabs is limited to
2
4
6
8
The maximum amount of dust which may be permitted in aggregates is
5% of the total aggregates for low workability with a coarse grading
10% of the total aggregates for low workability with a fine grading
20% of the total aggregates for a mix having high workability with fine grading
All the above
The commonly used material in the manufacture of cement is
Sand stone
Slate
Lime stone
Graphite
Too wet concrete may cause
Weakness of concrete
Excessive laitance
Segregation
All the above
The individual variation between test strength of sample should not be more than
± 5 % of average
± 10 % of average
± 15 % of average
± 20 % of average
The compressive strength of 100 mm cube as compared to 150 mm cube is always
Less
More
Equal
None of 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
For a simply supported beam of span 15 m, the minimum effective depth to satisfy the vertical deflection limits should be
600 mm
750 mm
900 mm
More than 1 m
Hydration of cement is due to chemical action of water with
Tricalcium silicate and dicalcium silicate
Dicalcium silicate and tricalcium aluminate
Tricalcium aluminate and tricalcium alumino ferrite
All the above
In counterfort retaining walls, the main reinforcement in the stem at support is
Not provided
Provided only on inner face
Provided only on front face
Provided both on inner and front faces
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 surface where two successive placements of concrete meet, is known as
Contraction joint
Expansion joint
Construction joint
Both (a) and (b)