The minimum cover to the ties or spirals should not be less than
15 mm
20 mm
25 mm
50 mm
Correct Answer :
C. 25 mm
Related Questions
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
Vicat apparatus is used for
Fineness test
Consistency test
Test for setting time
Test for tensile strength
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
Proper proportioning of concrete, ensures
Desired strength and workability
Desired durability
Water tightness of the structure
All the above
Workability of concrete for a given water content is good if the aggregates, are
Rounded aggregate
Irregular aggregate
Angular aggregate
Flaky aggregates
For a longitudinal reinforcing bar in a column, the minimum cover shall neither be less than the diameter of bar nor less than
15 mm
25 mm
30 mm
40 mm
The following proportion of the ingredients of concrete mix, is not in conformation to arbitrary method of proportioning
1 : 1 : 2
1 : 2 : 4
1 : 3 : 6
1 : 4 : 10
For ensuring quality of concrete, use
Single sized aggregates
Two sized aggregate
Graded aggregates
Coarse aggregates
The main reason for providing number of reinforcing bars at a support in a simply supported beam is to resist in that zone
Compressive stress
Shear stress
Bond stress
Tensile stress
Slump test of concrete is a measure of its
Consistency
Compressive strength
Tensile strength
Impact value
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
For road pavements, the cement generally used, is
Ordinary Portland cement
Rapid hardening cement
Low heat cement
Blast furnace slag cement
The operation of removing humps and hollows of uniform concrete surface, is known as
Floating
Screeding
Trowelling
Finishing
The ratio of the length to breadth of a wooden float, is
4.5
5.5
6.5
7.5
Pick up the correct statement from the following:
According to the petrological characteristics, concrete aggregates are classified as heavy weight, normal weight and light weight
According to the shape of the particles, concrete aggregates are classified as rounded irregular, angular and flaky
According to the surface texture of the particles, the concrete aggregates are classified as glassy, smooth, granular, rough, crystalline, honey combed and porous
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
Pick up the correct statement from the following:
The weight of ingredients of concrete mix, is taken in kilograms
Water and aggregates are measured in litres
20 bags of cement make one tonne
All the above
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 percentage of the aggregate of F.M. 2.6 to be combined with coarse aggregate of F.M. 6.8 for obtaining the aggregates of F.M. 5.4, is
30 %
40 %
50 %
60 %
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
A concrete having a slump of 6.5 cm, is said to be
Dry
Earth moist
Semi-plastic
Plastic
Concrete gains strength due to
Chemical reaction of cement with sand and coarse aggregates
Evaporation of water from concrete
Hydration of cement
All the above
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
A construction joint is provided where
Bending moment is small
Shear force is small
The member is supported by other member
All the above
Cube strength of controlled concrete to be used for pre-tensioned and post-tensioned work respectively should not be less than
35 MPa and 42 MPa
42 MPa and 35 MPa
42 MPa and 53 MPa
53 MPa and 42 MPa
If the various concrete ingredients i.e. cement, sand and aggregates are in the ratio of 1:3:6, the grade of concrete, is
M 100
M 150
M 200
M 250
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
The minimum cover to the ties or spirals should not be less than
15 mm
20 mm
25 mm
50 mm
Pick up the correct statement from the following:
Water enables chemical reaction to take place with cement
Water lubricates the mixture of gravel, sand and cement
Strength of concrete structure largely depends upon its workability
All the above
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