Deck 3: Concrete Design and Analysis

Question 1

On an absolutely rigid foundation base, the pressure will

A)Be more at the edges of the foundation
B)Be uniform
C)Not be uniform
D)Be zero at the centre of the foundation

Answer 1

Not be uniform

Question 2

The diameter of transverse reinforcement of columns should be equal to one-fourth of the diameter of the main steel rods but not less than

A)4 mm
B)5 mm
C)6 mm
D)7 mm

Answer 2

7 mm

Question 3

For a continuous floor slab supported on beams, the ratio of end span length and intermediate span length, is

A)0.6
B)0.7
C)0.8
D)0.9

Answer 3

0.9

Question 4

In a singly reinforced beam

A)Compression is borne entirely by concrete
B)Steel possesses initial stresses when embedded in concrete
C)Plane sections transverse to the centre line of the beam before bending remain plane after bending
D)Elastic moduli for concrete and steel have different values within the limits of deformation of the beam

Question 5

The ratio of the breadth to effective depth of a beam is kept

A)0.25
B)0.50
C)0.70
D)0.75

Question 6

A T-beam behaves as a rectangular beam of a width equal to its flange if its neutral axis

A)Remains within the flange
B)Remains below the slab
C)Coincides the geometrical centre of the beam
D)None of these

Question 7

The width of the rib of a T-beam, is generally kept between

A)1/7 to 1/3 of rib depth
B)1/3 to 1/2 of rib depth
C)1/2 to 3/4 of rib depth
D)1/3 to 2/3 of rib depth

Question 8

For the design of a simply supported T-beam the ratio of the effective span to the overall depth of the beam is limited to

A)10
B)15
C)20
D)25

Question 9

If the depth of actual neutral axis of a doubly reinforced beam

A)Is greater than the depth of critical neutral axis, the concrete attains its maximum stress earlier
B)Is less than the depth of critical neutral axis, the steel in the tensile zone attains its maximum stress earlier
C)Is equal to the depth of critical neutral axis; the concrete and steel attain their maximum stresses simultaneously
D)All the above

Question 10

The maximum diameter of a bar used in a ribbed slab, is

A)12 mm
B)6 mm
C)20 mm
D)22 mm

Question 11

If the diameter of the main reinforcement in a slab is 16 mm, the concrete cover to main bars is

A)10 mm
B)12 mm
C)14 mm
D)16 mm

Question 12

Minimum spacing between horizontal parallel reinforcement of different sizes, should not be less than

A)One diameter of thinner bar
B)One diameter of thicker bar
C)Twice the diameter of thinner bar
D)None of these

Question 13

The diameter of main bars in R.C.C. columns, shall not be less than

A)6 mm
B)8 mm
C)10 mm
D)12 mm

Question 14

Dimensions of a beam need be changed if the shear stress is more than

A)10 kg/cm²
B)15 kg/cm²
C)20 kg/cm²
D)25 kg/cm²

Question 15

The effective span of a simply supported slab, is

A)Distance between the centres of thebearings
B)Clear distance between the inner faces of the walls plus twice the thickness of the wall
C)Clear span plus effective depth of the slab
D)None of these

Question 16

The maximum ratio of span to depth of a cantilever slab, is

A)8
B)10
C)12
D)16

Question 17

An R.C.C. roof slab is designed as a two way slab if

A)It supports live loads in both directions
B)The ratio of spans in two directions is less than 2
C)The slab is continuous over two supports
D)The slab is discontinuous at edges

Question 18

In a combined footing for two columns carrying unequal loads, the maximum hogging bending moment occurs at

A)Less loaded column
B)More loaded column
C)A point of the maximum shear force
D)A point of zero shear force

Question 19

If the effective length of a 32 cm diameter R.C.C. column is 4.40 m, its slenderness ratio, is

A)40
B)45
C)50
D)55

Question 20

The radius of a bar bend to form a hook, should not be less than

A)Twice thediameter
B)Thrice thediameter
C)Four times the diameter
D)Five times the diameter

Question 21

A simply supported beam 6 m long and of effective depth 50 cm, carries a uniformly distributed load 2400 kg/m including its self weight. If the lever arm factor is 0.85 and permissible tensile stress of steel is 1400 kg/cm², the area of steel required, is

A)14 cm²
B)15 cm²
C)16 cm²
D)17 cm²

Question 22

The amount of reinforcement for main bars in a slab, is based upon

A)Minimum bendingmoment
B)Maximumbendingmoment
C)Maximum shear force
D)Minimum shearforce

Question 23

The diameter of longitudinal bars of a column should never be less than

A)6 mm
B)8 mm
C)10 mm
D)12 mm

Question 24

Steel beam theory is used for

A)Design of simple steel beams
B)Steel beams encased in concrete
C)Doubly reinforced beams ignoring compressive stress inconcrete
D)Beams if shear exceeds 4 times allowable shear stress