Practice Concrete Technology And Design Of Concrete Structures Multiple Choice Questions Quiz-3 - MCQGeeks.com

Q.1

For a continuous slab of 3 m x 3.5 m size, the minimum overall depth of slab to satisfy vertical deflection limits is

50 mm
75 mm
100 mm
120 mm

Q.2

According to ISI recommendations, the maximum depth of stress block for balanced section of a beam of effective depth d is

0.43 d
0.55 d
0.68 d
0.85 d

Q.3

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

L-shaped wall
T-shaped wall
counterfort type
all of the above

Q.4

In the design of a front counterfort in a counterfort retaining wall, the main reinforcement is provided on
i) bottom face near counterfort
ii) top face near counterfort
iii) bottom face near centre of span
iv) top face near centre of span
The correct answer is

only (i)
only (ii)
both (i) and (iv)
both (ii) and (iii)

Q.5

The main reinforcement in the toe of a T- shaped R C. retaining wall is provided on
i) top face parallel to the wall
ii) top face perpendicular to the wall
iii) bottom face paralleUo the wall
iv) bottom face perpendicular to the wall
The correct answer is

only (ii) is correct
(i) and (ii) are correct
(iii) and (iv) are correct
only (iv) is correct

Q.6

Shrinkage of concrete depends upon
i) humidity of atmosphere
ii) passage of time
iii) stress
The correct answer is

(i) and (ii)
(ii) and (iii)
only (iii)
All (i), (ii) and (iii)

Q.7

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

Q.8

Which of the following has high tensile strength ?

plain hot rolled wires
cold drawn wires
heat treated rolled wires
all have same tensile strength

Q.9

Select the correct statement

Elastic modulus of high tensile steel is nearly the same as that of mild steel
Elastic modulus of high tensile steel is more than that of mild steel
Carbon percentage in high carbon steel is less than that in mild steel
High tensile steel is cheaper than mild steel

Q.10

Select the incorrect statement

Lean mixes bleed more as compared to rich ones.
Bleeding can be minimized by adding pozzuolana finer aggregate.
Bleeding can be increased by addition of calcium chloride.
none of the above

Q.11

Select the incorrect statement

The loss of prestress is more in pre-tensioning system than in post-tensioning system.
Pretensioning system has greater certainty about its durability.
For heavy loads and large spans in buildings or bridges, post-tensioning system is cheaper than pretensioning system
none of the above

Q.12

In counterfort type retaining walls
i) the vertical slab is designed as a continuous slab
ii) the heel slab is designed as a continuous slab
iii) the vertical slab is designed as a cantilever
iv) the heel slab is designed as a cantilever
The correct answer is

(i) and (ii)
(i) and (iv)
(ii) and (iii)
(iii) and (iv)

Q.13

Sinking of an intermediate support of a continuous beam
i) reduces the negative moment at support
ii) increases the negative moment at support
iii) reduces the positive moment at center of span
iv) increases the positive moment at center of span
The correct answer is

(i) and (iii)
(i) and (iv)
(ii) and (iii)
(ii) and (iv)

Q.14

In a ring beam subjected to uniformly distributed load
i) shear force at mid span is zero
ii) shear force at mid span is maximum
iii) torsion at mid span is zero
iv) torsion at mid span is maximum
The correct answer is

(i) and (iii)
(i) and (iv)
(ii) and (iii)
(ii) and (iv)

Q.15

Normally prestressing wires are arranged in the

upper part of the beam
lower part of the beam
center
anywhere

Q.16

Modulus of rupture of concrete is a measure of

flexural tensile strength
direct tensile strength
compressive strength
split tensile strength

Q.17

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

rounded
elongated
angular
all of the above

Q.18

To minimize the effect of differential settlement, the area of a footing should be designed for

Dead load only
Dead load + live load
Dead load + fraction of live load
Live load + fraction of dead load

Q.19

The load carrying capacity of a helically reinforced column as compared to that of a tied column is about

5% less
10% less
5% more
10% more

Q.20

The minimum cover in a slab should neither be less than the diameter of bar nor less than

10 mm
15 mm
25 mm
13 mm

Q.21

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

Q.22

Minimum thickness of load bearing RCC wall should be

50 mm
100 mm
150 mm
200 mm

Q.23

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

Q.24

A T-shaped retaining wall mainly conssits of

one cantilever
two cantilevers
three cantilevers
four cantilevers

Q.25

Minimum grade of concrete to be used in reinforced concrete as per IS:456-1978 is

M15
M20
M10
M25

Q.26

The depth of footing for an isolated column is governed by
i) maximum bending moment
ii) shear force
iii) punching shear
The correct answer is

only (i)
(i) and (ii)
(i) and (iii)
(i), (ii) and (iii)

Q.27

In a counterfort retaining wall, the main reinforcement is provided on the
i) bottom face in front counterfort
ii) inclined face in front counterfort
iii) bottom face in back counterfort
iv) inclined face in back counterEort
The correct answer is

(i) and (ii),
(ii) and (iii)
(i) and (iv)
(iii) and (iv)

Q.28

The effect of adding calcium chloride in concrete is
i) to increase shrinkage
ii) to decrease shrinkage
iii) to increase setting time
iv) to decrease setting time
The correct answer is

(i) and (iii)
(i)and(iv)
(ii) and (iii)
(ii) and (iv)

Q.29

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

Q.30

The slab is designed as one way if the ratio of long span to short span is

less than 1
between 1 and 1.5
between 1.5 and 2
greater than 2

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