The effect of creep on modular ratio is
To decrease it
To increase it
Either to decrease or to increase it
To keep it unchanged
Correct Answer :
B. To increase it
Related Questions
M 150 grade of concrete approximates
1 : 3 : 6 mix
1 : 1 :2 mix
1 : 2 : 4 mix
1 : 1.5 : 3 mix
While compacting the concrete by a mechanical vibrator, the slump should not exceed
2.5 cm
5.0 cm
7.5 cm
10 cm
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
Pick up the correct statement from the following:
Water cement paste hardens due to hydration
During hardening cement binds the aggregates together
Cement provides strength, durability and water tightness to the concrete
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
The strength and quality of concrete, depend upon:
Grading of aggregates
Surface area of aggregates
Shape of aggregates
All the above
Pick up the incorrect statement from the following:
With passage of time, the strength of cement increases
With passage of time, the strength of cement decreases
After a period of 24 months, the strength of cement reduces to 50%
The concrete made with storage deteriorated cement, gains strength with time
As compared to ordinary Portland cement, use of pozzolana cement
Reduces workability
Increases bleeding
Increases shrinkage
Increases strength
Pick up the correct statement from the following:
Continuous grading is not necessary for obtaining a minimum of air voids
The omission of a certain size of aggregate is shown by a straight horizontal line on the grading curve
The omission of a certain size of aggregate in concrete increases the workability but also increases the liability to segregation
All the above
For a good concrete
Aggregates should be hard and durable
Water should be free from organic materials
Cement should be sufficient to produce the required strength
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
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
Most common method of pre-stressing used for factory production is
Long line method
Freyssinet system
Magnel-Blaton system
Lee-Macall system
Pick up the correct statement from the following:
The free water is the amount of water added while mixing and the amount of water held on the surface of the aggregates prior to mixing
The total water is the free water and the amount actually absorbed by the aggregates
Neither (a) nor (b)
Both (a) and (b)
The average permissible stress in bond for plain bars in tension is
Increased by 10% for bars in compression
Increased by 25% for bars in compression
Decreased by 10% for bars in compression
Decreased by 25% for bars in compression
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
According to IS: 4561978, the column or the strut is the member whose effective length is greater than
The least lateral dimension
2 times the least lateral dimension
3 times the least lateral dimension
4 times the least lateral dimension
Half of the main steel in a simply supported slab is bent up near the support at a distance of x from the center of slab bearing where x is equal to (Where l is the span)
l/3
l/5
l/7
l/10
The specifications of a cement bag for storage, are
Weight 50 kg
Height 18 cm
Plan area 3000 sq. cm
All the above
The factor which affects workability, is
Water content and its temperature
Shape and size of the aggregates
Air entraining agents
All the above
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 %
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 bulk density of aggregates, depends upon
Shape
Grading
Compaction
All the above
Addition of pozzolana to cement
Decreases workability
Increases strength
Increases heat of hydration
None of these
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
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
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
The high strength of rapid hardening cement at early stage, is due to its
Finer grinding
Burning at high temperature
Increased lime cement
Higher content of tricalcium
The size of fine aggregates does not exceed
2.75 mm
3.00 mm
3.75 mm
4.75 mm