According to IS 456 : 2000, the maximum diameter of reinforcing bars shall not exceed

One-tenth of total thickness of slab

One-fourth of total thickness of slab

One-sixth of total thickness of slab

One-eighth of total thickness of slab

One-tenth of total thickness of slab

Maximum horizontal distance between parallel main reinforcement bars in tension in RC slabs (according to IS 456:2000) shall not be :Take d = effective depth of solid slab

lesser than 5d or 300 mm whichever is smaller

lesser than 3d or 300 mm whichever is smaller

more than 3d or 300 mm whichever is smaller

lesser than 5d or 300 mm whichever is smaller

more than 5d or 450 mm whichever is smaller

A simply supported beam of overall depth 150 mm has neutral axis at 50 mm from extreme top fibre. Permissible flexural stresses in extreme compression and extreme tension fibre are restricted to 15 MPa and 25 MPa respectively. If the load on the beam is increased gradually, then:

failure of section will be due to stresses in extreme bottom fibre and extreme top fibre reaching to maximum permissible tensile and maximum permissible compressive stresses simultaneously

failure of section will be due to stresses in extreme top fibre reaching to maximum permissible tensile stresses

failure of section will be due to stresses in extreme in extreme bottom fibre reaching to maximum permissible tensile stresses

failure of section will be due to stresses in extreme bottom fibre and extreme top fibre reaching to maximum permissible tensile and maximum permissible compressive stresses simultaneously

failure of section will be due to stresses in extreme top fibre reaching to maximum permissible compressive stresses

Along the neutral axis in a beam

fibres undergo maximum elongation

For limit state design of RC beam consider following:i) \(\left[ {\frac{{{f_y}}}{{{f_{ck}}}} = 0.36} \right]\)ii) \(\left[ {\frac{{{A_{st}}}}{{bd}} = 4\% } \right]\)iii) \(\left[ {\frac{{{x_{u\;max}}}}{d} = 0.48} \right]\)Which one of the design criteria shall be applicable?

both balanced and over reinforced sections

Critical section for shear in case of flat slabs is (adopting standard notations)

at a distance of effective depth of slab from the periphery of the column/the drop panel

at a distance of \(\frac{d}{2}\) from the periphery of the column/the capital / the drop panel

IS 456 : 2000 recommends to provide certain minimum steel in RCC beam:-

to avoid rupture of steel in case a flexural failure occurs

to hold the stirrups in position

to provide enough ductility to the beam

A T-beam behaves as a rectangular beam of width equal to its flange if it’s neutral axis

Coincides with centroid of reinforcement

Coincides with centroid of T section

According to IS 456:2000, the HYSD reinforcement in either direction of the slab shall not be less than:

0.15% of the total cross-sectional area

0.10% of the total cross-sectional area

0.12% of the total cross-sectional area

0.15% of the total cross-sectional area

0.20% of the total cross-sectional area

Focusing 'material efficiency’, which of the following is the correct sequence?

Two-way slab > T beam > Rectangular beam

T-beam > Rectangular beam >Two-way slab

Two-way slab > T beam > Rectangular beam

Two-way slab < T beam < Rectangular beam

Maximum shear force for three equal spans of beam/slab occur at ?

inner side of support next to end support

outer side of support next to end support

A rectangular beam of width 230 mm and effective depth 300 mm is proposed to carry a BM and SF of 120 kNm and 270 kN, respectively. If M 30 grade of concrete and Fe 415 steel are used for which τc max = 3.5 MPa, which one of the following statements is correct?

It can be designed as a singly reinforced, under-reinforced section

It can be designed as a doubly reinforced section

The section is unsafe from shear considerations

It can be designed as a doubly reinforced section but it is unsafe from shear considerations

In an under reinforced section, the depth of actual neutral axis is

more than the maximum depth of neutral axis or Xu > Xumax

less that the maximum depth of neutral axis or Xu < Xumax

more than the maximum depth of neutral axis or Xu > Xumax

equal to the maximum depth of neutral axis or Xu = Xumax

equal to the half of depth of beam or Xu = d / 2

In a rectangular reinforced concrete section, the shape of the shear stress diagram as per IS456 is

rectangular over the full depth

parabolic above the neutral axis and rectangular below the neutral axis

rectangular over the full depth

rectangular above the neutral axis and parabolic below the neutral axis

Deep beams are designed for

Both shear force and bending moment

A doubly reinforced beam is considered less economical than a singly reinforced beam because:

Tensile steel required is more than that for balanced section

Compressive steel is under stressed

Tensile steel required is more than that for balanced section

Concrete is not stressed to its full value

In the design of the slab, the diameter of reinforcing bars shall not exceed

one-fourth of overall thickness of slab

one-eighth of overall thickness of slab

one-fourth of overall thickness of slab

one-half of overall thickness of slab

one-third of overall thickness of slab

In case of one-way continuous slab, maximum bending moment will be at:

interior support other than next to end support

67 + Mcqs in Beams And Slabs in Prestressed Concrete Structures Page 1 McqOptions

1.	In reinforced brickwork slabs, the diameter of main reinforcement shall, preferable not exceed
A.	8 mm
B.	10 mm
C.	12 mm
D.	16 mm
Answer» D. 16 mm

2.	In case of a non-cellular, non-ribbed flat slab, the spacing of the steel reinforcing bars shall not exceed m times the thickness of the slab, wherein m is
A.	1.5
B.	1.2
C.	1.9
D.	2
E.	3
Answer» E. 3

3.	In absence of detailed design, approximately how much percentage for steel reinforcement may be considered for estimation of RCC lintels
A.	1.0 to 5.0 %
B.	0.7 to 1.0%
C.	0.2 to 0.5 %
D.	1.0 to 10.0%
Answer» C. 0.2 to 0.5 %

5.	A rectangular beam 200 mm wide has an effective depth of 350 mm. It is subjected to a bending moment of 24,000 Nm. The permissible stresses are c = 5 N/mm2, t = 140 N/mm2; and m is 18. The required area of tensile reinforcement will be
A.	688 mm2
B.	778 mm2
C.	864 mm2
D.	954 mm2
Answer» C. 864 mm2

7.	According to IS 3414, the recommended spacing of expansion joints for thin unprotected slabs is
A.	30 m
B.	45 m
C.	6 m
D.	12 m
E.	15 m
Answer» F.

8.	A reinforced concrete cantilever porch has thickness t. The main reinforcement steel will be placed:
A.	At mid-thickness.
B.	At t/3 from the top.
C.	Close to the bottom surface.
D.	Close to the top surface.
Answer» E.

9.	According to IS 456, when high strength deformed bars are used, the reinforcement shall not be less than p percent of the total cross sectional area of the slab, where p is
A.	0.12
B.	0.15
C.	0.1
D.	0.09
E.	0.16
Answer» B. 0.15

10.	Minimum area of tension reinforcement in a beam shall be greater than:-
A.	0.85bd/fy
B.	0.87 fy/bd
C.	0.4bd fy
D.	0.04 bd
Answer» B. 0.87 fy/bd

11.	Maximum compression reinforcement in beams is given by:
A.	0.04bd
B.	0.05bd
C.	0.04bD
D.	0.12bD
Answer» D. 0.12bD

12.	In doubly reinforced beams, the percentage of the maximum compression reinforcement of the gross cross sectional area of beam should not exceed:-
A.	2%
B.	4%
C.	5%
D.	3%
Answer» C. 5%

14.	In a two-way spanning slab, if corners of the slab are not allowed to lift, torsion reinforcement is provided at corners in the form of a mesh. The size of mesh should be equal to
A.	0.125 lx × 0.125 ly
B.	0.125 lx × 0.25 ly
C.	0.25 lx × 0.25 ly
D.	0.20 lx × 0.20 ly
Answer» E.

15.	In a doubly-reinforced beam, if c and t are stresses in concrete and tension reinforcement, d is the effective depth and n is the depth of critical neutral axis n, the following relationship holds good
A.	mc/t = n/(d - n)
B.	(m + c)/t = n/(d + n)
C.	(t + c)/m = (d + n)/n
D.	mc/t = (d - n)/t
Answer» B. (m + c)/t = n/(d + n)

21.	If W is load on a circular slab of radius R, the maximum radial moment at the centre of the slab is-
A.	\(\frac{{W{R^2}}}{{16}}\)
B.	\(\frac{{3W{R^2}}}{{32}}\)
C.	\(\frac{{W{R^2}}}{{32}}\)
D.	\(\frac{{3W{R^2}}}{{16}}\)
Answer» E.

23.	A RCC slab under mild exposure condition having main longitudinal tensile reinforcement of diameter 12 mm, then minimum allowable nominal cover to satisfy durability requirement is
A.	10 mm
B.	15 mm
C.	20 mm
D.	25 mm
Answer» C. 20 mm

26.	A ribbed slab is provided for which of the following?
A.	a plain ceiling
B.	thermal insulation
C.	acoustic insulation
D.	All option are correct
Answer» E.

16.	A reinforced cement concrete beam section has a size of 300 mm width and 400 mm effective depth, the grade of concrete used is M20 and grade of steel is Fe 415. If the ultimate bending moment of 150 kN-m acts at the section, the beam has to be designed as
A.	Singly reinforced beam
B.	Doubly reinforced beam
C.	Beam cannot be designed
D.	Balanced beam
Answer» C. Beam cannot be designed

17.	A reinforced concrete slab is 75 mm thick. The maximum size of the reinforcement bar that can be used is:
A.	6 mm diameter
B.	8 mm diameter
C.	10 mm diameter
D.	12 mm diameter
Answer» C. 10 mm diameter

18.	Area of the side face reinforcement of a beam where the depth of web exceeds 750 mm shall be not less than:
A.	0.25% of web area
B.	0.15% of web area
C.	0.10% of web area
D.	0.8% of web area
Answer» D. 0.8% of web area

19.	Along the neutral axis in a beam
A.	fibres undergo maximum strain
B.	fibres undergo maximum elongation
C.	fibres undergo minimum strain
D.	fibres do not undergo strain
Answer» E.

20.	For limit state design of RC beam consider following:i) \(\left[ {\frac{{{f_y}}}{{{f_{ck}}}} = 0.36} \right]\)ii) \(\left[ {\frac{{{A_{st}}}}{{bd}} = 4\% } \right]\)iii) \(\left[ {\frac{{{x_{u\;max}}}}{d} = 0.48} \right]\)Which one of the design criteria shall be applicable?
A.	Balanced section
B.	Over - reinforced section
C.	Under reinforced section
D.	both balanced and over reinforced sections
Answer» D. both balanced and over reinforced sections

24.	IS 456 : 2000 recommends to provide certain minimum steel in RCC beam:-
A.	to avoid rupture of steel in case a flexural failure occurs
B.	to ensure compression failure
C.	to hold the stirrups in position
D.	to provide enough ductility to the beam
Answer» B. to ensure compression failure

25.	If any tension reinforcement in an RC beam attains its yield stress during loading before the concrete in the compression zone fails due to crushing, the beam is said to be
A.	under-reinforced
B.	over-reinforced
C.	balanced
D.	non-homogeneous
Answer» B. over-reinforced

29.	An RCC slab (M 25 grade), of dimensions 5 m × 5 m × 0.15 m, is supported on four square columns (M 25 grade) of side 400 mm, the clear height of each column being 3 m. Assuming rigid connections, the fundamental time period of vibration of the slab along the horizontal direction is nearly.
A.	4.12 s
B.	2.80 s
C.	0.062 s
D.	1.07 s
Answer» D. 1.07 s

30.	For a simply supported beam of span 12 m, the basic value of span to effective depth ratio is
A.	20
B.	26
C.	65/3
D.	50/3
Answer» E.

31.	In simple supported beam main reinforcement is provided at ______ of beam
A.	Top
B.	Middle
C.	Bottom
D.	Anywhere as per site condition
Answer» D. Anywhere as per site condition

Explore topic-wise MCQs in Prestressed Concrete Structures.

In reinforced brickwork slabs, the diameter of main reinforcement shall, preferable not exceed

In case of a non-cellular, non-ribbed flat slab, the spacing of the steel reinforcing bars shall not exceed m times the thickness of the slab, wherein m is

In absence of detailed design, approximately how much percentage for steel reinforcement may be considered for estimation of RCC lintels

According to IS 456 : 2000, the maximum diameter of reinforcing bars shall not exceed

A rectangular beam 200 mm wide has an effective depth of 350 mm. It is subjected to a bending moment of 24,000 Nm. The permissible stresses are c = 5 N/mm2, t = 140 N/mm2; and m is 18. The required area of tensile reinforcement will be

Maximum horizontal distance between parallel main reinforcement bars in tension in RC slabs (according to IS 456:2000) shall not be :Take d = effective depth of solid slab

According to IS 3414, the recommended spacing of expansion joints for thin unprotected slabs is

A reinforced concrete cantilever porch has thickness t. The main reinforcement steel will be placed:

According to IS 456, when high strength deformed bars are used, the reinforcement shall not be less than p percent of the total cross sectional area of the slab, where p is

Minimum area of tension reinforcement in a beam shall be greater than:-

Maximum compression reinforcement in beams is given by:

In doubly reinforced beams, the percentage of the maximum compression reinforcement of the gross cross sectional area of beam should not exceed:-

A simply supported beam of overall depth 150 mm has neutral axis at 50 mm from extreme top fibre. Permissible flexural stresses in extreme compression and extreme tension fibre are restricted to 15 MPa and 25 MPa respectively. If the load on the beam is increased gradually, then:

In a two-way spanning slab, if corners of the slab are not allowed to lift, torsion reinforcement is provided at corners in the form of a mesh. The size of mesh should be equal to

In a doubly-reinforced beam, if c and t are stresses in concrete and tension reinforcement, d is the effective depth and n is the depth of critical neutral axis n, the following relationship holds good

A reinforced cement concrete beam section has a size of 300 mm width and 400 mm effective depth, the grade of concrete used is M20 and grade of steel is Fe 415. If the ultimate bending moment of 150 kN-m acts at the section, the beam has to be designed as

A reinforced concrete slab is 75 mm thick. The maximum size of the reinforcement bar that can be used is:

Area of the side face reinforcement of a beam where the depth of web exceeds 750 mm shall be not less than:

Along the neutral axis in a beam

For limit state design of RC beam consider following:i) \(\left[ {\frac{{{f_y}}}{{{f_{ck}}}} = 0.36} \right]\)ii) \(\left[ {\frac{{{A_{st}}}}{{bd}} = 4\% } \right]\)iii) \(\left[ {\frac{{{x_{u\;max}}}}{d} = 0.48} \right]\)Which one of the design criteria shall be applicable?

If W is load on a circular slab of radius R, the maximum radial moment at the centre of the slab is-

Critical section for shear in case of flat slabs is (adopting standard notations)

A RCC slab under mild exposure condition having main longitudinal tensile reinforcement of diameter 12 mm, then minimum allowable nominal cover to satisfy durability requirement is

IS 456 : 2000 recommends to provide certain minimum steel in RCC beam:-

If any tension reinforcement in an RC beam attains its yield stress during loading before the concrete in the compression zone fails due to crushing, the beam is said to be

A ribbed slab is provided for which of the following?

A T-beam behaves as a rectangular beam of width equal to its flange if it’s neutral axis

According to IS 456:2000, the HYSD reinforcement in either direction of the slab shall not be less than:

An RCC slab (M 25 grade), of dimensions 5 m × 5 m × 0.15 m, is supported on four square columns (M 25 grade) of side 400 mm, the clear height of each column being 3 m. Assuming rigid connections, the fundamental time period of vibration of the slab along the horizontal direction is nearly.

For a simply supported beam of span 12 m, the basic value of span to effective depth ratio is

In simple supported beam main reinforcement is provided at ______ of beam

Focusing 'material efficiency’, which of the following is the correct sequence?

Maximum shear force for three equal spans of beam/slab occur at ?

A rectangular beam of width 230 mm and effective depth 300 mm is proposed to carry a BM and SF of 120 kNm and 270 kN, respectively. If M 30 grade of concrete and Fe 415 steel are used for which τc max = 3.5 MPa, which one of the following statements is correct?

If area of steel for maximum mid span moment is 205 mm2, what would be the area of steel required for the corner?

In an under reinforced section, the depth of actual neutral axis is

In a rectangular reinforced concrete section, the shape of the shear stress diagram as per IS456 is

If the permissible compressive and tensile stresses in a singly reinforced beam are 20 MPa and 250 MPa respectively, and if the neutral axis depth is limited to 0.3 times the effective depth of the section, then the percentage area of the steel required for an economic section is (using WSM)

A simply supported beam of span 6 m is resting on a 230 mm wide brick wall. Assumed depth of beam is 85 mm per 1 m span, and also assume width of the beam equals width of the support. The factored dead load of the beam is ______.

Deep beams are designed for

In design of slab, as per IS-456, what should be minimum percent of distribution steel if Fe 415 reinforcement is used ?

A doubly reinforced beam is considered less economical than a singly reinforced beam because:

In the design of the slab, the diameter of reinforcing bars shall not exceed

If the length of an intermediate span of a continuous slab is 5 m , the length of the end span is kept

If reinforcement in a beam is cut parallel to its length in the plan, the reinforcement will be represented in section as which of the following options?

In case of one-way continuous slab, maximum bending moment will be at:

A simply supported isolated ‘T’ beam of 6m span shown below is used as a walkway. The effective width of the flange is:-

In a cantilever beam carrying gravity load, main reinforcement is provided

In singly reinforced beams, steel main reinforcement is provided in

32.	Focusing 'material efficiency’, which of the following is the correct sequence?
A.	T-beam > Rectangular beam >Two-way slab
B.	T-beam < Rectangular beam < b>
C.	Two-way slab > T beam > Rectangular beam
D.	Two-way slab < T beam < Rectangular beam
Answer» C. Two-way slab > T beam > Rectangular beam

33.	Maximum shear force for three equal spans of beam/slab occur at ?
A.	inner side of end support
B.	inner side of support next to end support
C.	outer side of support next to end support
D.	outer side of end support
Answer» D. outer side of end support

35.	If area of steel for maximum mid span moment is 205 mm2, what would be the area of steel required for the corner?
A.	153.75 mm2
B.	205 mm2
C.	102.5 mm2
D.	41 mm2
Answer» B. 205 mm2

37.	In a rectangular reinforced concrete section, the shape of the shear stress diagram as per IS456 is
A.	parabolic over the full depth
B.	parabolic above the neutral axis and rectangular below the neutral axis
C.	rectangular over the full depth
D.	rectangular above the neutral axis and parabolic below the neutral axis
Answer» C. rectangular over the full depth

38.	If the permissible compressive and tensile stresses in a singly reinforced beam are 20 MPa and 250 MPa respectively, and if the neutral axis depth is limited to 0.3 times the effective depth of the section, then the percentage area of the steel required for an economic section is (using WSM)
A.	0.56%
B.	0.76%
C.	0.86%
D.	1.20%
Answer» E.

39.	Consider the following statements:1. The minimum steel requirements of slabs are based on considerations of shrinkage and temperature effects alone, and not on strength.2. Providing excessive reinforcement in beams can result in congestion, thereby adversely affecting the proper placement and compaction of concrete.Which of the above statements is/are correct?
A.	1 only
B.	2 only
C.	Both 1 and 2
D.	Neither 1 nor 2
Answer» D. Neither 1 nor 2

40.	A simply supported beam of span 6 m is resting on a 230 mm wide brick wall. Assumed depth of beam is 85 mm per 1 m span, and also assume width of the beam equals width of the support. The factored dead load of the beam is ______.
A.	21.11 kN
B.	26.39 kN
C.	17.6 kN
D.	30.2 kN
Answer» C. 17.6 kN

41.	Deep beams are designed for
A.	Shear force only
B.	Bending moment only
C.	Both shear force and bending moment
D.	Bearing
Answer» C. Both shear force and bending moment

42.	In design of slab, as per IS-456, what should be minimum percent of distribution steel if Fe 415 reinforcement is used ?
A.	0.12% of total cross-section
B.	0.15% of total cross-section
C.	0.50% of total cross-section
D.	1% of total cross-section
Answer» B. 0.15% of total cross-section

43.	A doubly reinforced beam is considered less economical than a singly reinforced beam because:
A.	Shear reinforcement is more
B.	Compressive steel is under stressed
C.	Tensile steel required is more than that for balanced section
D.	Concrete is not stressed to its full value
Answer» C. Tensile steel required is more than that for balanced section