According to IS : 382-1963, a good aggregate should be
Chemically inert
Sufficiently strong
Hard and durable
All the above
Correct Answer :
D. All the above
Related Questions
In symmetrically reinforced sections, shrinkage stresses in concrete and steel are respectively
Compressive and tensile
Tensile and compressive
Both compressive
Both tensile
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
If a grading curve is horizontal between the portions of 20 mm I.S. Sieve and 4.75 mm I.S. Sieve, the graded aggregates do not contain
20 mm particles
10 mm particles
4.75 mm particles
All the above
According to IS: 4561978, minimum slenderness ratio for a short column is
Less than 12
Less than 18
Between 18 and 24
More than 24
If the depth of moist sand in a cylinder is 15 cm and the depth of the sand when fully inundated with water is 12 cm, the bulking of the moist sand, is
10 %
12 %
15 %
25 %
After casting, an ordinary cement concrete on drying
Expands
Mix
Shrinks
None of these
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 rock which is not calcareous, is:
Lime stone
Chalk
Laterite
None of these
Specified compressive strength of concrete is obtained from cube tests at the end of
3 days
7 days
21 days
28 days
The strength of concrete after one year as compared to 28 days strength is about
10 to 15% more
15 to 20% more
20 to 25% more
25 to 50% more
The limits of percentage p of the longitudinal reinforcement in a column is given by
0.15% to 2%
0.8% to 4%
0.8% to 6%
0.8% to 8%
The main object of compaction of concrete, is:
To eliminate air holes
To achieve maximum density
To provide intimate contact between the concrete and embedded materials
All the above
Minimum grade of concrete to be used in reinforced concrete as per IS: 4561978 is
M 15
M 20
M 10
M 25
Le-Chatelier's apparatus is used for testing
Soundness of cement
Hardness of cement
Strength of cement
Durability of cement
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:
Bulking of sand is caused due to formation of a thin film of surface moisture
Fine sand bulks more than coarse sand
The volume of fully saturated sand, is equal to the volume of dry and loose sand
All the above
Curing of pavements, floors, roofs and slabs, is done by
Membrane method
Ponding method
Covering surface with bags
Sprinkling water method
According to Whitney's theory, ultimate strain of concrete is assumed to be
0.03 %
0.1 %
0.3 %
3 %
On a grading curve, the gap grading is represented by
A horizontal line
A vertical line
N.W. inclined line
N.E. inclined line
Di-calcium silicate (C2S)
Hydrates rapidly
Generates less heat of hydration
Hardens rapidly
Provides less ultimate strength to cement
In the design of a front counterfort in a counterfort retaining wall, the main reinforcement is provided on (i) Bottom face near counterfort (ii) Top face near counterfort (iii) Bottom face near centre of span (iv) Top face near centre of span The correct answer is
Only (i)
Only (ii)
Both (i) and (iv)
Both (ii) and (iii)
Separation of coarse aggregates from mortar during transportation, is known
Bleeding
Creeping
Segregation
Shrinkage
For concreting tunnel linings, transportation of concrete is done by
Pans
Wheel borrows
Containers
Pumps
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
During erection, the pile of length l is supported by a crane at a distance of
0.207 l
0.293 l
0.707 l
0.793 l From the driving end of pile which rests on the ground
Curing a concrete for long period ensures better
Volume stability
Strength
Water resistance
All the above
The bulk density of aggregates, depends upon
Shape
Grading
Compaction
All the above
The type of aggregates of same nominal size, which contain less voids when compacted, are
Rounded spherical
Irregular
Flaky
None of these
The cement whose strength is a little lower than the ordinary cement during the first three months but attains afterwards the same strength, is known as
Low-heat Portland cement
Rapid hardening Portland cement
Portland blast slag cement
Portland pozzolana cement
Bulking of sand is
Mixing of different sizes of sand particles
Mixing of lime with sand
Maximum water with sand
Swelling of sand when wetted