Concrete Technology And Design Set 10 MCQs

Q1 | Modulus of elasticity of steel as per IS: 4561978 shall be taken as

20 kn/cm²

200 kn/cm²

200 kn/mm²

2 × 106 n/cm²

Q2 | The grade of concrete M 150 means that compressive strength of a 15 cm cube after 28 days, is

100 kg/cm2

150 kg/cm2

200 kg/cm2

250 kg/cm2

Q3 | The cement becomes useless if its absorbed moisture content exceeds

1 %

2 %

3 %

5 %

Q4 | In reinforced concrete footing on soil, the minimum thickness at edge should not be less than

100 mm

150 mm

200 mm

250 mm

Q5 | For preparing a test-specimen, it is necessary

to mix cement and fine aggregate by dry hand

to mix coarse aggregates

to mix water to the cement, fine aggregates and coarse aggregates

all the above

Q6 | 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

Q7 | The process of hardening the concrete by keeping its surface moist is known

placing

wetting

curing

compacting

Q8 | For the construction of the retaining structures, the type of concrete mix to be used, is

1 : 3 : 6

1 : 2 : 4

1 : 1½ : 3

1 : 4 : 8

Q9 | The produce impermeable concrete

thorough mixing of concrete is required

proper compaction of concrete is required

proper curing of concrete is required

all the above

Q10 | Pozzolanic properties exist in

shales

fly ash

pumicite

all the above

Q11 | A continuous beam is deemed to be a deep beam when the ratio of effective span to overall depth(1/D) is less than

1.5

2.0

2.5

3.0

Q12 | 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

Q13 | If fineness modulus of sand is 2.5, it is graded as

very fine sand

fine sand

medium sand

coarse sand

Q14 | Maximum quantity of water needed per 50 kg of cement for M 15 grade of concrete is

28 liters

30 liters

32 liters

34 liters

Q15 | The increased cohesiveness of concrete, makes it

less liable to segregation

more liable to segregation

more liable to bleeding

more liable for surface scaling in frosty weather

Q16 | Concrete is unsuitable for compaction by a vibrator if it is

dry

earth moist

semi-plastic

plastic

Q17 | In order to obtain the best workability of concrete, the preferred shape of aggregate is

rounded

elongated

angular

all of the above

Q18 | 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

Q19 | An aggregate which passes through 25 mm I.S. sieve and is retained on 20 mm sieve, is said to beflaky if its least dimension is less than

22.5 mm

18.5 mm

16.5 mm

13.5 mm

Q20 | Approximate value of shrinkage strain in concrete, is

0.003

0.0003

0.00003

0.03

Q21 | For quality control of Portland cement, the test essentially done is

setting time

tensile strength

consistency

all the above

Q22 | Strength of concrete with passage of time

increases

decreases

fluctuates

remains constant

Q23 | Which of the following statements is incorrect?

higher vee-bee time shows lower workability

higher slump shows higher workability

higher compacting factor shows higher workability

none of the above

Q24 | To obtain cement dry powder, lime stones and shales or their slurry, is burnt in a rotary kiln at atemperature between

1100° and 1200°c

1200° and 1300°c

1300° and 1400°c

1400° and 1500°c

Q25 | In a pile of length , the points of suspension from ends for lifting it are located at

0.207 l

0.25 l

0.293 l

0.333 l