Concrete Technology And Design Set 3 MCQs

Q1 | For the construction of thin R.C.C. structures, the type of cement to be avoided, is

ordinary portland cement

rapid hardening cement

low heat cement

blast furnace slag cement

Q2 | Which of the following R.C. retaining walls is suitable for heights beyond 6 m?

l-shaped wall

t-shaped wall

counterfort type

all of the above

Q3 | For batching 1:3:6 concrete mix by volume, the ingredients required per bag of 50 kg cement, are:

70 litres of sand and 120 litres of aggregates

70 kg of sand and 140 litres of aggregates

105 litres of sand and 140 litres of aggregates

105 litres of sand and 210 litres of aggregates

Q4 | A concrete using an air entrained cement

has strength less than 10% to 15%

has more resistance to weathering

is more plastic and workable

is free from segregation and bleeding

Q5 | Pick up the correct statement from the following:

segregation is necessary for a workable concrete

consistency does not affect the workability of concrete

if the concrete mix is dry, the slump is maximum

none of these

Q6 | The surface where two successive placements of concrete meet, is known as

contraction joint

expansion joint

construction joint

both (a) and (b)

Q7 | A beam curved in plan is designed for

bending moment and shear

bending moment and torsion

shear and torsion

bending moment, shear and torsion

Q8 | 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

Q9 | 'Ware house pack' of cement means

full capacity of the ware house

pressure exertion of the bags of upper layers

pressure compaction of the bags on lower layers

packing the ware house

Q10 | High carbon content in the steel causes

decrease in tensile strength but increase in ductility

increase in tensile strength but decrease in ductility

decrease in both tensile strength and ductility

increase in both tensile strength and ductility

Q11 | Particles of 0.002 mm size are that of

clay

sand

gravel

none of these

Q12 | Ultimate strength of cold drawn high steel wires

increases with increase in diameter of bar

decreases with increase in diameter of bar

does not depend on diameter of bar

none of the above

Q13 | The cement whose strength is a little lower than the ordinary cement during the first threemonths but attains afterwards the same strength, is known as

low-heat portland cement

rapid hardening portland cement

portland blast slag cement

portland pozzolana cement

Q14 | The dimensions of a 35 litre forma for measuring aggregates by volume, are:

length 30 cm, breadth 25 cm, height 30 cm

length 39 cm, breadth 25 cm, height 32 cm

length 27 cm, breadth 27 cm, height 48 cm

length 220 cm, breadth 25 cm, height 40 cm

Q15 | Ratio of permissible stress in direct compression and bending compression is

less than 1

between 1 and 1.5

between 1.5 and 2.0

greater than 2

Q16 | Concrete containing

siliceous aggregates, has higher co-efficient of expansion

igneous aggregates, has intermediate coefficient of expansion

lime stones, has lowest co-efficient of expansion

all the above

Q17 | The lower water cement ratio in concrete, introduces

smaller creep and shrinkage

greater density and smaller permeability

improved frost resistance

all the above

Q18 | In T-shaped R C. retaining walls, the main reinforcement in the stem is provided on

the front face in one direction

the front face in both directions

the inner face in one direction

the inner face in both directions

Q19 | 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

Q20 | Pick up the correct statement from the following:

construction joints in columns are provided a few cm below the junction of beam

construction joints in columns are provided at the bottom hunching

construction joints in beams and slabs are provided within middle third

all the above

Q21 | According to ISI recommendations, the maximum depth of stress block for balanced section of abeam of effective depth d is

0.43 d

0.55 d

0.68 d

0.85 d

Q22 | Pick up the correct proportions of chemical ingredients of cement

lime : silica : alumina : iron oxide : 63 : 22 : 6 : 3

silica : lime : alumina : iron oxide : 63 : 22 : 6 : 3

alumina : silica : lime : iron oxide : 63 : 22 : 6 : 3

iron oxide : alumina : silica : lime : 63 : 22 : 6 : 3

Q23 | Internal friction between the ingredients of concrete, is decreased by using

less water

fine aggregates

rich mix

more water and coarse aggregates

Q24 | Pick up the correct statement from the following:

the quality of water governs the strength of concrete

10% excess of water reduces the strength of concrete by 15%

30% excess of water reduces the strength of concrete by 50%

all the above

Q25 | Pick up the correct statement from the following:

lime in excess, causes the cement to expand and disintegrate

silica in excess, causes the cement to set slowly

alumina in excess, reduces the strength of the cement

all the above