Concrete Technology And Design Set 11 MCQs

Q1 | Curing a concrete for long period ensures better

volume stability

strength

water resistance

all the above

Q2 | Batching error means inaccuracy in the quantity of

aggregates

cement

water

all the above

Q3 | If the storey height is equal to length of RCC wall, the percentage increase in strength is

0

10

20

30

Q4 | If X, Y and Z are the fineness modulli of coarse, fine and combined aggregates, the percentage (P)of fine aggregates to combined aggregates, is

p = [(z - x)/(z - y)] × 100

p = [(x - z)/(z - y)] × 100

p = [(x - z)/(z + y)] × 100

p = [(z + x)/(z - y)] × 100

Q5 | If the depth of actual neutral axis in a beam is more than the depth of critical neutral axis, then thebeam is called

balanced beam

under-reinforced beam

over-reinforced beam

none of the above

Q6 | Proper proportioning of concrete, ensures

desired strength and workability

desired durability

water tightness of the structure

all the above

Q7 | The relation between modulus of rupture fcr, splitting strength fcs and direct tensile strength fcl isgiven by

fcr - fcs = fcl

fcr > fcs > fcl

fcr < fcs < fcl

fcs > fcr > fcl

Q8 | Air entrainment in the concrete increases

workability

strength

the effects of temperature variations

the unit weight

Q9 | Construction joints are provided

where b.m. and s.f. are small

where the member is supported by other member

at 18 m apart in huge structures

all the above

Q10 | Maximum distance between expansion joints in structures as per IS: 456 1978 is

20 m

30 m

45 m

60 m

Q11 | Ordinary concrete is not used for concrete grade

m 100

m 150

m 250

m 400

Q12 | In a spherical dome subjected to concentrated load at crown or uniformly distributed load, themeridional force is always

zero

tensile

compressive

tensile or compressive

Q13 | An aggregate is said to be flaky, if its least dimension is less than

2/3 mean dimension

3/4 mean dimension

3/5 mean dimension

5/8 mean dimension

Q14 | While designing an air entrained concrete

water cement ratio is reduced

proportion of aggregates is reduced

an allowance for the entrained air is made

all the above

Q15 | Minimum thickness of load bearing RCC wall should be

50 mm

100 mm

150 mm

200 mm

Q16 | M 150 grade of concrete approximates

1 : 3 : 6 mix

1 : 1 :2 mix

1 : 2 : 4 mix

1 : 1.5 : 3 mix

Q17 | Permissible compressive strength of M 300 concrete grade is

100 kg/cm2

150 kg/cm2

200 kg/cm2

300 kg/cm2

Q18 | Strength of concrete increases with

increase in water-cement ratio

increase in fineness of cement

decrease in curing time

decrease in size of aggregate

Q19 | For ensuring quality of concrete, use

single sized aggregates

two sized aggregate

graded aggregates

coarse aggregates

Q20 | In working stress design, permissible bond stress in the case of deformed bars is more than that inplain bars by

10 %

20 %

30 %

40 %

Q21 | Workability improved by adding

air-entraining agent

foaming agent

oily-agent

all the above

Q22 | The rock which is not calcareous, is:

lime stone

chalk

laterite

none of these

Q23 | A T-shaped retaining wall mainly consists of

one cantilever

two cantilevers

three cantilevers

four cantilevers

Q24 | Pick up the correct statement from the following:

insufficient quantity of water makes the concrete mix harsh

insufficient quantity of water makes the concrete unworkable

excess quantity of water makes the concrete segregated

all the above

Q25 | The fineness modulus of fine aggregate is in the range of

2.0 to 3.5

3.5 to 5.0

5.0 to 7.0

6.0 to 8.5