Showing posts with label RCC Questions. Show all posts
Showing posts with label RCC Questions. Show all posts

RCC Questions (R7)

In this post, I will share some important questions which are frequently asked in competitive examinations such as SSC, UPSC and state PSCs.



  1. The main reinforcement of an RC slab consists of 10 mm bars at 10 cm spacing. If it is desired to replace 10 mm bars by 12 mm bars, then the spacing of 12 mm bars should be


    1. 12 cm
    2. 14 cm
    3. 14.40 cm
    4. 16 cm

    View Answer
    Answer: c
    This question was asked in IES [95].
    Let's say the spacing of 10 mm bar is $x$ and that of 12 mm bar is $y$

    $\frac{1}{x} \times \text{area of 10 mm bar} = \frac{1}{y} \times \text{area of 12 mm bar}$

    $y= \frac{\pi \times 12^2/4}{\pi \times 10^2 /4} \times 10 = 14.40 cm$

  2. Torsion resisting capacity of a given RCC section


    1. Decreases with the decrease in stirrups spacing
    2. Decreases with the increase in longitudinal bars
    3. Does not depend upon stirrup and longitudinal steel
    4. Increases with the increase in the stirrup and longitudinal steel

    View Answer
    Answer: d
    This question was asked in IES [95].
    An increase in the area of stirrups and longitudinal bars increases the stiffness of RCC section and therefore, the torsion resistance capacity of the section increases.

  3. The one-way slab is designed ...


    1. as a beam whose width is equal to the shorter span of the slab
    2. as a beam of unit width
    3. by using Marcus' Method
    4. Any of the above

    View Answer
    Answer: b

  4. Which of the following method is used to design a 2-way slab simply supported on the four edges with corners not held down and carrying UDL?


    1. Grashoff-Rankine Method
    2. Pigeaud's Method
    3. Marcus' Method
    4. None of the above

    View Answer
    Answer: a

  5. The deflection in a two-way slab as compared to the one-way slab is ...


    1. equal
    2. much smaller
    3. much larger
    4. a little less

    View Answer
    Answer: b

  6. As per IS 456, the length of the middle strip of a two-way slab is ...


    1. 1/2 of the span
    2. 1/3 of the span
    3. 3/4 of the span
    4. 2/3 of the span

    View Answer
    Answer: c
    As per IS 456, Fig 25, It is 3/4 of the span.

  7. In case of 2-way slab, the limiting deflection of the slab is ...


    1. primarily a function of the long span
    2. primarily a function of the short span
    3. independent of the long or short span
    4. dependent on both long and short spans

    View Answer
    Answer: b
    This question was asked in IES [95]
    As per IS 456, Cl 24.1 [Note], the short span is used to calcuate depth/effective depth ratio. From this, we can say that in a 2-way slab, the limiting deflection is primarily a function of the short span.

  8. Select the correct statement.
    Moment and shear coefficients for continuous beams and slabs can be used when ...


    1. there are minimum 3 spans which differ by not more than 15% of the longest span
    2. there are maximum 3 spans which differ by not more than 15% of the longest span
    3. there are minimum 3 spans which differ by not more than 25% of the longest span
    4. there are maximum 3 spans which differ by not more than 25% of the longest span

    View Answer
    Answer: a
    As per IS 456:2000, Cl 22.5.1, these coefficients can be used only when the numbers of spans are 3 or more which differ by not more than 15% of the longest span.

  9. A continuous RC beam spans 6 span segments, each supporting a monolithic reinforced concrete slab.
    The beam will best be designed ...


    1. as a rectangular one throughout the span
    2. as a T-beam throughout the span
    3. as a rectangular beam for span moments and T-beam for support moments
    4. as a T-beam for span moments and rectangular beam for support moments

    View Answer
    Answer: d
    This question was asked in IES [2002]
    At supports there will be hogging moment i.e., tension will be above NA and compression will be below NA. As concrete is weak in tension, the beam at supports should be designed as a rectangular beam.
    For span moments, the beam is designed as T-beam, as due to monolithic reinforced concrete slab, some part of the slab will act as a flange for the beam at each of 6 span segments.

  10. Shrinkage in a concrete slab ...


    1. causes shear cracks
    2. causes tension cracks
    3. causes compression cracks
    4. does not cause any cracking

    View Answer
    Answer: b
    This question was asked in IES [2002]
    Cracking due to shrinkage occurs due to restraints that cause tensile stresses and strains in concrete.

  11. A flat slab is supported by ...


    1. beams
    2. walls
    3. columns
    4. all of the above

    View Answer
    Answer: c

  12. What is the minimum thickness of a flat slab?


    1. 100 mm
    2. 125 mm
    3. 150 mm
    4. 175 mm

    View Answer
    Answer: b
    As per IS 456:2000, Cl 31.2.1, the minimum thickness is 125 mm.

  13. A thick rectangular portion below the flat slab is called ____.


    1. Column head
    2. Capital
    3. Drop
    4. none of the above

    View Answer
    Answer: c

  14. The width of a column strip in a flat slab is ...


    1. 1/2 of the span
    2. 1/3 of the span
    3. 1/4 of the span
    4. 1/5 of the span

    View Answer
    Answer: c
    As per IS 456:2000, Cl 31.1.1 [a], the width of the column strip is $0.25 {l}_{2}$ but not greater than $0.25 {l}_{1}$. Where, ${l}_{1}$ is the span in the direction moments are being determined and ${l}_{2}$ is the transverse span to ${l}_{1}$





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RCC Questions (R6)

In this post, I will share some important questions which are frequently asked in competitive examinations such as SSC, UPSC and state PSCs.



  1. How diagonal tension reinforcement is provided in a beam?


    1. Longitudinal Bars
    2. Helical reinforcement
    3. Bent-up bars
    4. None of the above

    View Answer
    Answer: c

  2. Why minimum shear reinforcement is provided in a beam?


    1. To resist the bond stress at the support
    2. To resist shear at the support
    3. To arrest the longitudinal cracks on side faces due to shrinkage and temperature variation.
    4. All of the above

    View Answer
    Answer: c
    The minimum shear reinforcement is provided in a beam so that beam does not fail in shear when the shear strength of concrete gets reduced due to tension-induced into the beam through shrinkage or some restraint.

  3. The maximum value of permissible shear stress is based on ...


    1. Diagonal tension failure
    2. Diagonal compression failure
    3. Flexural compression failure
    4. Flexural tension failure

    View Answer
    Answer: b
    The maximum permissible shear stress is based on diagonal compression failure because if the total area of stirrups and bent-up bars exceed a certain limit, the section might become stronger in diagonal tension as compared to diagonal compression. Hence, a shear compression failure may occur even before the shear reinforcement has yielded and that is an undesirable situation as the nature of the failure is brittle.

  4. The first crack formed in a deep beam is ...


    1. Diagonal crack due to tension
    2. Diagonal crack due to compression
    3. Shear crack
    4. Flexural crack

    View Answer
    Answer: a

  5. What will be the maximum spacing between vertical stirrups in an RCC beam when the effective depth is 300 mm?


    1. 250 mm
    2. 300 mm
    3. 275 mm
    4. 225 mm

    View Answer
    Answer: d
    The maximum spacing is the minimum of 0.75 times the effective depth of beam and 300 mm.

  6. An RCC beam of effective depth 1 m and effective span 10 m is supported on columns of size 500 mm X 500 mm. If the beam is loaded with a UDL of 10 MN/m then what is the design shear force?


    1. 37.5 MN
    2. 50 MN
    3. 43 MN
    4. 47.5 MN

    View Answer
    Answer: a
    The critical section is 1 m from the face of the support and 1.25 m from the centre of the support.
    shear force at support is 50 MN
    Design Shear force $=50-10\times (0.25+1)=37.5$ MN

  7. Which of the following is correct for compression steel?


    1. ${L}_{d}=\frac{\phi {\sigma}_{s}}{4 {\tau}_{bd}}$
    2. ${L}_{d}=\frac{\phi {\sigma}_{s}}{5 {\tau}_{bd}}$
    3. ${L}_{d}=\frac{\phi {\sigma}_{s}}{6.4 {\tau}_{bd}}$
    4. ${L}_{d}=\frac{\phi {\sigma}_{s}}{8 {\tau}_{bd}}$

    View Answer
    Answer: b
    In the case of compresstion steel the bond stress is increased by 25%.

  8. How bond stress gets changed when HYSD bars are used?


    1. Its value increased by 25%
    2. Its value decreased by 25%
    3. Its value increased by 50%
    4. Its value decreased by 50%

    View Answer
    Answer: c

  9. The term "${M}_{1}/V$" in the expression ${L}_{d}\leq {M}_{1}/V + {L}_{0}$ is increased by ____ when the reaction is compressive.


    1. 25%
    2. 30%
    3. 45%
    4. 60%

    View Answer
    Answer: b
    As per IS 456, Cl 26.2.3.3, the term ${M}_{1}/V$ is increased by 30%.

  10. In above question, what is the value of ${L}_{0}$?


    1. The effective depth of the member
    2. 12 times the diameter of the bar
    3. Smaller of (a) and (b)
    4. Greater of (a) and (b)

    View Answer
    Answer: d
    As per IS 456, CL 26.2.3.3, it is greater of the first two options.

  11. Which of the following statements is incorrect?


    1. If the bars are larger than 36 mm in diameter, Lap splices are not generally provided.
    2. Lap length including anchorage value of hooks for the bar in flexural tension shall be ${L}_{d}$ or $12 \phi$, whichever is greater.
    3. The straight length of the lap shall not be less than $12 \phi$ or 200 mm.
    4. None of the above

    View Answer
    Answer: c
    As per IS 456, Cl 26.2.5.1 [c], it is $15 \phi$ or 200 mm.

  12. If "D" is the diameter of the bar, then what is the anchorage value of the U-hook?


    1. 12D
    2. 16D
    3. 18D
    4. 20D

    View Answer
    Answer: b
    As per IS 456, Cl 26.2.2.1 [b-2], it's "16D"

  13. What is the radius of a U type hook (Mild steel)?


    1. 4 times the diameter
    2. 3 times the diameter
    3. 2 times the diameter
    4. none of the above

    View Answer
    Answer: c
    As per IS 2502, Fig 1, (Note), the radius is "KD" and K is 2 for mild steel and 4 for HYSD bar.

  14. When the splices are welded in compression then the strength of the weld is taken as ...


    1. 100 % of the design strength of the joined bars
    2. 80 % of the design strength of the joined bars
    3. 90 % of the design strength of the joined bars
    4. 750 % of the design strength of the joined bars

    View Answer
    Answer: a
    As per IS 456, Cl 26.2.5.2, it is 100 % of the design strength of the joined bars when the splices are in compression.
    If the bars are spliced in tension then the strength of weld is 80 % of the design strength of the welded bars and 100 % of design strength of the mechanical connection.





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RCC Questions (R5)

In this post, I will share some important questions which are frequently asked in competitive examinations such as SSC, UPSC and state PSCs.



  1. When side reinforcement is used in a beam?


    1. the depth of web exceeds 500 mm
    2. the depth of web exceeds 750 mm
    3. the depth of web exceeds 1000 mm
    4. the depth of web exceeds 1250 mm

    View Answer
    Answer: b
    As per IS 456, Cl 26.5.1.3, when the depth of the web exceeds 750 mm, side reinforcement is provided.

  2. What is the minimum percentage of side reinforcement?


    1. 0.1
    2. 0.5
    3. 2.0
    4. 4.0

    View Answer
    Answer: a
    The total minimum side reinforcement to be provided on both side is 0.1 %.

  3. The actual curtailment point of tension reinforcement in flexural member shall be beyond the theoretical curtailment point by ...


    1. the effective depth of the member
    2. 12 times the bar diameter
    3. greater of (a) and (b)
    4. smaller of (a) and (b)

    View Answer
    Answer: c
    As per IS 456, Cl 26.3.2.1, it greater of option (a) and (b).

  4. Select the correct option regarding the extension of the positive moment reinforcement into the support.


    1. at least 1/3 reinforcement in simple members
    2. at least 1/4 reinforcement in continuous members
    3. length of the extension is ${L}_{d}/3$
    4. All are correct

    View Answer
    Answer: d
    Extension of positive reinforcement is done as per IS 456, cl 26.2.3.3

  5. The extension of negative moment reinforcement beyond the point of inflection is ...


    1. 12 times bar diameter
    2. 1/16 of the clear span
    3. smaller of (a) and (b)
    4. greater of (a) and (b)

    View Answer
    Answer: d
    As per IS 456, Cl 26.2.3.4, it is greater of option (a) and (b)

  6. What is the shape of the shear stress distribution above the neutral axis of a beam as per elastic theory?


    1. rectangular
    2. cubic
    3. parabolic
    4. circular

    View Answer
    Answer: c

  7. Flexural cracks make an angle of _____ with the vertical.


    1. $0^\circ$
    2. $30^\circ$
    3. $45^\circ$
    4. $90^\circ$

    View Answer
    Answer: a

  8. Which of the following is the region of diagonal tension cracks?


    1. midspan
    2. adjacent to support
    3. where shear force is significant
    4. where both shear force and bending moment are significant

    1. only (i)
    2. only (ii)
    3. both (ii) and (iii)
    4. both (ii) and (iv)

    View Answer
    Answer: c

  9. Shear span is a zone where


    1. bending moment is zero
    2. shear force is zero
    3. bending moment is constant
    4. shear force is constant

    View Answer
    Answer: d

  10. At which angle (to the horizontal) the shear failure will normally occur in beams and cantilevers without shear reinforcement?


    1. $0^\circ$
    2. $30^\circ$
    3. $45^\circ$
    4. $90^\circ$

    View Answer
    Answer: b
    As per IS 456, Cl 4.5.1, it is $30^\circ$ to the horizontal


  11. At which place the critical section for shear will lie in the case of a secondary beam?


    1. the face of the support
    2. at a distance of effective depth of the beam
    3. at a distance of half the effective depth of the beam
    4. none of the above

    View Answer
    Answer: a
    When support offers a tensile reaction, the critical section for shear for such a case is at the face of the support.
    For more info see IS 456, cl 22.6.2

  12. Maximum spacing between shear reinforcement bar in a beam is ...


    1. 0.75 times the effective depth
    2. 300 mm
    3. smaller of (a) and (b)
    4. greater of (a) and (b)

    View Answer
    Answer: c
    As per IS 456, Cl 26.5.1.5, it is smaller of option (a) and (b)

  13. When nominal shear stress in a beam is not greater than the permissible shear stress then ...


    1. nominal shear reinforcement still provided
    2. no shear reinforcement is provided
    3. shear reinforcement is provided for the difference of nominal and permissible shear stress
    4. none of the above

    View Answer
    Answer: a
    As per IS 456, Cl 40.3, minimum reinforcement is provided when nominal shear stress is less than permissible shear stress.

  14. Shear reinforcement is provided in the form of ...


    1. vertical stirrups
    2. bent-up bars
    3. inclined stirrups
    4. all of the above

    View Answer
    Answer: d

  15. The maximum value of shear stress for a solid slab is ...


    1. equal to that for beam
    2. equal to half to that for beam
    3. equal to 1.5 times to that for beam
    4. equal to twice to that for beam

    View Answer
    Answer: b
    As per IS 456, Cl 40.2.3.1, for solid slabs, maximum shear stress is half to that for beams.





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RCC Questions (R4)

In this post, I will share some important questions which are frequently asked in competitive examinations such as SSC, UPSC and state PSCs.



  1. The location of neutral axis in a T beam is ...


    1. in the web
    2. in the flange
    3. at the intersection of web and flange
    4. either (a) or (b) or (c)

    View Answer
    Answer: d

  2. If NA of a T beam lies within flange then ...


    1. the beam is designed as a rectangular beam
    2. the concrete area in the web will be ignored
    3. both (a) and (b)
    4. the beam is designed as a T beam

    View Answer
    Answer: c
    If NA lies within the depth of the flange than, the concrete below the NA can be ignored as it can not take tension and such T-beam is design as a rectangular beam of width equal to flange width.

  3. If roof slab and beam supporting it act monolithically then which of the following is correct.


    1. the beam is designed as T beam
    2. the beam is designed as a rectangular beam
    3. design of beam will depend upon the depth of NA
    4. none of the above

    View Answer
    Answer: c

  4. Which of the following is not an advantage of compression steel used in a doubly reinforced beam?


    1. it reduces the long-term deflection and increases the ductility of the beam.
    2. it makes the beam more economical than the singly reinforced beam.
    3. it permits the smaller size of the beam.
    4. it can be used as anchor bars.

    View Answer
    Answer: b
    In a doubly reinforced beam, compression steel is under stressed and hence they doubly reinforced beam is less economical than the singly reinforced beam.

  5. Consider the following statements and choose the correct option.


    1. failure of an under-reinforced beam is called compression failure.
    2. failure of an over reinforced beam is called tensile failure.

    1. both statements are correct
    2. both statements are wrong
    3. only statement (1) is correct
    4. only statement (2) is correct

    View Answer
    Answer: b
    failure of an under-reinforced beam is called tensile failure because under ultimate state the tension steel yields significantly before a strain of 0.0035 occurs in the concrete. This failure is also called ductile failure.
    failure of an over reinforced beam is called compression or brittle failure because concrete reaches the crushing strain and yielding of tensile steel is not significant.

  6. Select the incorrect statement.


    1. In an over reinforced section, the moment of resistance increases rapidly.
    2. In an under-reinforced section, the moment of resistance nearly proportional to the percentage of tension steel.
    3. The rate of gain of the moment of resistance increases with the use of higher grade of steel.
    4. In higher grade, steel balanced section is reached at a smaller percentage of steel.

    View Answer
    Answer: a

  7. What is the minimum percentage of mild steel provided in a slab?


    1. 0.12
    2. 0.15
    3. 0.18
    4. 0.20

    View Answer
    Answer: b
    As per IS 456, Cl 26.5.2.1, It is 0.15% for mild steel and 0.12 for HYSD bars.

  8. The maximum ratio of the total depth of the slab and diameter of steel bar is ...


    1. 4
    2. 6
    3. 7
    4. 8

    View Answer
    Answer: d
    As per IS 456, Cl 26.5.2.2, the Maximum diameter of steel bar in a slab can be 1/8th of the overall depth of the slab.

  9. Which of the following is the function(s) of transverse reinforcement in a slab?


    1. it distributes the effects of point load on the slab evenly and uniformly.
    2. it distributes the shrinkage and temperature cracks more evenly.
    3. it keeps the main reinforcement in position.
    4. all of the above.

    View Answer
    Answer: d

  10. What is the spacing between the main reinforcement in a slab?


    1. 3 times the effective depth of the slab
    2. 300 mm
    3. Smaller of the above two
    4. Greater of the first two options

    View Answer
    Answer: c
    As per IS 456, Cl 26.3.3 (b-1), it is 3 times the effective depth or 300 mm (whichever is smaller)

  11. What is the spacing between the main reinforcement in a slab?


    1. 5 times the effective depth of the slab
    2. 450 mm
    3. Smaller of the above two
    4. Greater of the first two options

    View Answer
    Answer: c
    As per IS 456, Cl 26.3.3 (b-2), it is 5 times the effective depth or 450 mm (whichever is smaller)

  12. Steel bars are bent up at a distance of _______ from the centre of the support in slabs.


    1. l/5
    2. l/6
    3. l/7
    4. l/8

    Where l is the centre to centre span

    View Answer
    Answer: c

  13. The triangular load on a lintel makes an angle of ____ on its base with the vertical.


    1. $30^\circ$
    2. $45^\circ$
    3. $60^\circ$
    4. $70^\circ$

    View Answer
    Answer: a

  14. There is slab over a lintel, intersecting the load dispersion triangle. The load acting on the lintel will be...


    1. load due to masonry between the lintel and the slab.
    2. self-weight of the slab of length equal to the length of the lintel.
    3. triangular load on the slab
    4. addition of the above

    View Answer
    Answer: d





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RCC Questions (R3)

In this post, I will share some important questions which are frequently asked in competitive examinations such as SSC, UPSC and state PSCs.



  1. As per IS 456, Which of the following is the ratio to limit the vertical deflection of a simply supported beam?


    1. 7
    2. 20
    3. 26
    4. no such limit

    View Answer
    Answer: b
    As per IS 456 Cl 23.2.3, the ratio of span to effective depth for a simply supported beam is 20.

  2. If the span of a simply supported beam is 12, then what will be its effective depth?


    1. 1.7 m
    2. 0.6 m
    3. 0.72 m
    4. 0.462 m

    View Answer
    Answer: c
    Since the span is over 10m, the ratio for simply supported beam (20) will be modified by a factor "20/(span in meter)"
    $\frac{12}{\text{effective depth}}=20 \times \frac{10}{12}$
    $\text{effective depth}=0.72 m$

  3. The deflection including the effects of temperature, creep and shrinkage occurring after the erection of partitions and the application of finishes should not exceed _______.


    1. span/350
    2. 20 mm
    3. span/250
    4. lesser of (a) and (b)

    View Answer
    Answer: d
    As per IS:456, Cl 23.2 (b), it is lesser of span/350 and 20 mm.

  4. The effective depth and width of a cantilever beam are 380 mm and 200 mm. What should be the maximum clear span so that the beam stays laterally stable?


    1. 5 m
    2. 10.5 m
    3. 12 m
    4. 7 m

    View Answer
    Answer: a
    As per IS: 456, Cl 23.3, a cantilever is laterally stable if its clear span does not exceed $25 \times width$ or $100 {b^2}/d$ whichever is less

  5. Which of the following slabs is a one-way slab?


    1. 10 m X 15 m
    2. 15 m X 30 m
    3. 4 m X 7 m
    4. 8 m X 3 m

    View Answer
    Answer: d
    One-way slabs are those slabs in which ratio of longer span to shorter span is greater than 2.

  6. What is the span to overall depth ratio for the two-way simply supported slab reinforced with HYSD bars?


    1. 28
    2. 35
    3. 40
    4. 32

    View Answer
    Answer: a
    As per IS: 456 Cl 24.1 (Note-2), Ratio is 35 and if HYSD bar is used the ratio is multiplied by 0.8.

  7. What is the maximum reinforcement allowed in compression zone of a beam?


    1. $0.04 \times bD$
    2. $0.04 \times bd$
    3. $0.01 \times bD$
    4. $0.01 \times bd$

    Where, b,d and D are the width, effective depth and overall depth of a beam

    View Answer
    Answer: a
    As per IS: 456 Cl 26.5.1.2, it is $0.04 \times bD$

  8. The width of a beam is 250 mm and exposure condition is mild. If 600 $mm^2$ reinforcement is to be provided using 16 mm bars then what will be the centre to centre spacing between the steel bars?


    1. 102 mm
    2. 97 mm
    3. 92 mm
    4. 88 mm

    View Answer
    Answer: b
    Since the exposure condition is "mild", the nominal cover as per IS:456 Table 16 is 20 mm
    Number of bars required is 3
    C/C distance $=\frac{250- 2\times 20 -2\times 8}{2} = 97 mm$

  9. What is the maximum limit on lateral sway under transient wind load?


    1. H/350
    2. H/400
    3. H/450
    4. H/500
    Where H is the total height of the building.


    View Answer
    Answer: d
    As per IS:456, cl 20.5, limit to lateral sway is H/500

  10. What is the effective span for an intermediate span?


    1. The clear span between supports
    2. The clear span between supports plus the effective depth of the beam/slab
    3. The clear span between supports plus width of the support
    4. Lesser of (b) and (c)

    View Answer
    Answer: a
    As per IS:456, Cl 22.2 (b1), for continuous spans, For end span with one end fixed and the other continuous or for intermediate spans, the effective span shall be the clear span between supports.

  11. Which of the following is correct regarding Flanged Beam?


    1. The slab shall be cast integrally with the web, or the web and the slab shall be effectively bonded together in any other manner.
    2. If the main reinforcement of the slab is parallel to the beam, transverse reinforcement shall be provided, such reinforcement shall not be less than 50 percent of the main reinforcement mid-span of the slab.
    3. Both (a) and (b)
    4. Neither (a) nor (b)

    View Answer
    Answer: a
    As per IS:456, Cl 23.1.1, The slab shall be cast integrally with the web, or the web and the slab shall be effectively bonded together in any other manner.
    If the main reinforcement of the slab is parallel to the beam, transverse reinforcement shall be provided, such reinforcement shall not be less than 60 per cent of the main reinforcement mid-span of the slab.

  12. For heavy load condition, what may be the overall depth of a continuous T-beam?


    1. 1/12 to 1/15 of the span
    2. 1/15 to 1/20 of the span
    3. 1/10 to 1/12 of the span
    4. 1/8 to 1/12 of the span

    View Answer
    Answer: c
    For light loads = 1/15 to 1/20 of the span
    For medium loads = 1/12 to 1/15 of the span
    For heavy loads = 1/10 to 1/12 of the span

  13. An isolated T-beam has a flange width of 1 m, flange thickness 80 mm rib width of 240 mm and effective depth of 400 mm, simply supported over a span of 4m. What is the effective width of the flange?


    1. 1000 mm
    2. 940 mm
    3. 850 mm
    4. 740 mm

    View Answer
    Answer: d
    Effective width of flange is given by,
    ${b}_{f}=\frac{{l}_{0}}{\frac{{l}_{0}}{b}+4}+{b}_{w}$
    ${b}_{f}=\frac{4000}{\frac{4000}{1000}+4}+{240}=740 mm$

  14. What is the depth of the neutral axis of a beam of effective depth 400 mm and width of 250 mm? Area of steel is 600 $mm^2$ $m=19$.


    1. 240 mm
    2. 242 mm
    3. 243 mm
    4. 244 mm

    View Answer
    Answer: b
    $\frac{b\times x^2}{2}=m\times{A}_{st}(d-x)$





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RCC Questions (R2)

In this post, I will share some important questions which are frequently asked in competitive examinations such as SSC, UPSC and state PSCs.



  1. What is the ratio of permissible stress in bending compression and that of direct compression for M20 grade concrete?


    1. less than 1.5
    2. 1
    3. less than 1
    4. greater than 1.5

    View Answer
    Answer: a
    permissible stress in bending compression and that of direct compression is 7 $N/mm^2$ and 5 $N/mm^2$ respectively.

  2. Select the incorrect statement.


    1. Cold working is the process in which bar is stretched beyond the yield plateau either by twisting or stretching.
    2. The lugs or rugs on the deformed bar minimises the slippage of the bar in concrete
    3. Cold working increases the ductility of mild steel
    4. The yield stress of cold worked bars are specified at 0.2% proof stress

    View Answer
    Answer: c
    The process of cold working reduces the ductility of mild steel.

  3. What is the permissible stress of Fe 415 steel in tension?


    1. 415 $N/mm^2$
    2. 230 $N/mm^2$
    3. 190 $N/mm^2$
    4. 140 $N/mm^2$

    View Answer
    Answer: b
    As per IS 456, Table-22, it is 230 $N/mm^2$

  4. At which place the tension reinforcement is provided in a cantilever beam?


    1. above neutral axis
    2. below neutral axis
    3. at the neutral axis
    4. Any of the above

    View Answer
    Answer: a
    Since the tension is above the NA in a cantilever, therefore, tension reinforcement is provided above NA.

  5. Consider the following equation and select the correct statements.


    1. At any cross-section, plane sections before bending remain plane after bending
    2. The concrete and steel are well bonded
    3. After the cracking, concrete bears the same amount of tension as that of steel
    4. Young's modulus of concrete is generally found by Rankine's method from the stress-strain curve.

    1. All are correct
    2. Options (i) and (iii)
    3. Options (i) and (ii)
    4. Options (ii) and (iv)

    View Answer
    Answer: c
    All tensile stresses are taken by the steel alone.
    Young's modulus of concrete is generally found by Secant method from the stress-strain curve.

  6. For an uncracked section of a beam, what is the net increase in the equivalent concrete area?


    1. $m{A}_{st}$
    2. $(m-1){A}_{st}$
    3. $0.5(m-1){A}_{st}$
    4. $1.5(m){A}_{st}$

    Where, $m=$modular ratio and ${A}_{st}=$ Area of steel


    View Answer
    Answer: b

  7. Neutral axis depth factor is given by ...


    1. $\frac{1}{1+\frac{r}{m}}$
    2. $\frac{1}{1+\frac{m}{r}}$
    3. $\frac{r}{1+\frac{1}{m}}$
    4. $\frac{1}{m+\frac{r}{m}}$

    Where, $r=$ Stress ratio and $m=$ Modular ratio


    View Answer
    Answer: a

  8. What is the value of the modular ratio for M25 grade concrete?


    1. 10.98
    2. 3.73
    3. 13.33
    4. 93.33

    View Answer
    Answer: a
    As per IS 456, Modular ratio $= \frac{280}{3\times {\sigma}_{cbc}}$
    ${\sigma}_{cbc}=8.5$ $N/mm^2$ for M25 grade of concrete.

  9. Consider the following statements and select the appropriate option.


    1. For compression reinforcement modular ratio is taken as 1.5 times the modular ratio
    2. The long-term effect of creep and shrinkage of concrete and non-linearity at higher strains in concrete results in much larger compressive stress in compression steel than those indicated by linear elastic theory using normally specified value of the modular ratio

    1. Both statements are correct and (ii) is the correct explanation of (i)
    2. Both statements are correct and (ii) is the incorrect explanation of (i)
    3. (i) is correct but (ii) is wrong
    4. (ii) is correct but (i) is wrong

    View Answer
    Answer: a

  10. What is the value of constant (R) for a Balanced moment of resistance for M20 Grade concrete and Fe 250 steel?


    1. 1.2138 $N/mm^2$
    2. 0.91 $N/mm^2$
    3. 3.468 $N/mm^2$
    4. 2.6 $N/mm^2$

    View Answer
    Answer: a
    $R=\frac {1}{2}\times {J}{K}{\sigma}_{cbc}$

    $K=\frac{1}{1+ \frac{r}{m}}$

    $J=1-\frac{K}{3}$

    $R = 0.1734 \times {\sigma}_{cbc}=1.2138$ $N/mm^2$

  11. If $d$ is the effective depth and $x$ is the neutral axis of the beam, then the lever arm is given by ...


    1. $d-x$
    2. $d/x$
    3. $d-\frac{x}{2}$
    4. $d-\frac {x}{3}$

    View Answer
    Answer: d

  12. Select the correct statement


    1. In under reinforced section, concrete reaches its permissible limit of stress prior to steel
    2. In under reinforced section, steel is provided is more than required for a balanced section
    3. In under reinforced section, the actual neutral axis is above the critical neutral axis
    4. none of the above

    View Answer
    Answer: c
    In under reinforced section, steel reaches its permissible limit of stress prior to concrete.
    In under reinforced section, steel is provided is less than required for a balanced section

  13. The effective depth and width of a beam are 450 mm and 250 mm respectively. The M20 grade of concrete and Fe 250 steel is used. What will be the minimum tensile reinforcement if applied moment is 10 KNm?


    1. 183 $N/mm^2$
    2. 102.52 $N/mm^2$
    3. 212.5 $N/mm^2$
    4. 382.5 $N/mm^2$

    View Answer
    Answer: d
    As per IS 456, cl 26.5.1.1, minimum tensile reinforcement is,
    ${A}_{s}=\frac{0.85 \times bd}{{f}_{y}}$

  14. The effective depth and depth Neutral axis is 300 mm and 160 mm. M20 grade concrete and Fe 415 is used. If the section is overly-reinforced what will be the stress in steel?


    1. 230 $N/mm^2$
    2. 81.64 $N/mm^2$
    3. 140 $N/mm^2$
    4. 6.125 $N/mm^2$

    View Answer
    Answer: b






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RCC Questions (R1)

In this post, I will share some important questions which are frequently asked in competitive examinations such as SSC, UPSC and state PSCs.



  1. Which of the following IS codes is used for Plain and Reinforced Concrete?


    1. IS 455: 1989
    2. IS 456: 2000
    3. IS 800: 2007
    4. IS 875: 1987

    View Answer
    Answer: b

  2. What is the minimum grade of concrete recommended for reinforced concrete work?


    1. M10
    2. M15
    3. M20
    4. M25

    View Answer
    Answer: c
    As per Table 5 of IS 456: 2000, the minimum grade of concrete to be used is M20.

  3. The strength of the material below which not more than 5% of the test results are expected to fall is called _______.


    1. Characteristic Strength
    2. Working Strength
    3. Flexural Strength
    4. None of the above

    View Answer
    Answer: a

  4. What is the total shrinkage strain of concrete?


    1. 0.003
    2. 0.0003
    3. 0.0035
    4. 0.002

    View Answer
    Answer: b
    As per IS 456:2000, cl 6.2.4.1, The total shrinkage strain for design may be taken as 0.0003.

  5. What is the flexural strength of M25 grade of concrete?


    1. 2.5 $N/mm^2$
    2. 3 $N/mm^2$
    3. 3.25 $N/mm^2$
    4. 3.5 $N/mm^2$

    View Answer
    Answer: d
    Flexural Strength $=0.7\sqrt{{f}_{ck}}$
    $=3.5 N/mm^2$

  6. Select the correct statement.


    1. Short term modulus of Elasticity of concrete is directly proportional to the characteristic strength of concrete
    2. Short term modulus of Elasticity of concrete is directly proportional to square root of the characteristic strength of concrete
    3. Short term modulus of Elasticity of concrete is inversely proportional to square root of the characteristic strength of concrete
    4. Short term modulus of Elasticity of concrete is not related to the characteristic strength of concrete

    View Answer
    Answer: b
    As per IS 456:2000, cl 6.3.2.1, Short-term modulus of elasticity of concrete is given by,
    ${E}_{c}=5000 \sqrt{{f}_{ck}}$

  7. Concrete surface exposed to seawater spray comes under which if the following environmental exposure condition?


    1. Moderate
    2. Severe
    3. Very severe
    4. Extreme

    View Answer
    Answer: c
    As per IS 456:2000 Table-3, this condition comes under very severe environment.

  8. What is the minimum grade of concrete to be used in RCC, when the surface is exposed directly along the sea coast?


    1. M20
    2. M25
    3. M30
    4. M35

    View Answer
    Answer: c
    As per IS 456, cl 8.2.8, M30 to be used for RCC and M20 to be used for PCC.

  9. For which grades Nominal mix may be used?


    1. M5 or lower
    2. M10 or lower
    3. M15 or lower
    4. M20 or lower

    View Answer
    Answer: d
    As per IS 456, Cl 9.1.1, for grades M20 or lower, the nominal mix may be used with the permission of Engineer-in-charge.

  10. What is the tolerance limit (in percent) for measuring equipment measuring cement and water?


    1. $\pm 3$ and $\pm 2$
    2. $\pm 2$ and $\pm 3$
    3. $\pm 2$ and $\pm 2$
    4. $\pm 3$ and $\pm 3$

    View Answer
    Answer: b
    As per IS 456, Cl 10.2.2, it is $\pm 2$ % and $\pm 3$ %.

  11. What is the minimum period to remove props to arches spanning over 6 m?


    1. 7 days
    2. 14 days
    3. 21 days
    4. 28 days

    View Answer
    Answer: c
    As per IS 456, Cl 11.3.1, it is 21 days.

  12. What is the maximum free fall of concrete?


    1. 0.5 m
    2. 1 m
    3. 1.5 m
    4. 2 m

    View Answer
    Answer: c
    As per IS 456, cl 13.2, the maximum free fall is 1.5 m

  13. What is the minimum of the radius of bent at construction joints, if HYSD bars are used?


    1. 6 times the diameter of the bar
    2. 4 times the diameter of the bar
    3. 3 times the diameter of the bar
    4. 5 times the diameter of the bar

    View Answer
    Answer: a
    As per IS 456, cl 12.5, 6 times the diameter of the bar for HYSD and 4 times the dia of the bar for plain mild steel bar.

  14. As per IS 456, what is the minimum time for which curing is to be done?


    1. 7 days
    2. 14 days
    3. 21 days
    4. 28 days

    View Answer
    Answer: a
    As per IS 456. cl 13.5, minimum time period is 7 days.

  15. The individual variation should not be more than ____ percent of the average test result.


    1. $\pm 5$
    2. $\pm 10$
    3. $\pm 12$
    4. $\pm 15$

    View Answer
    Answer: d
    As per IS 456, cl 15.4, it is $\pm 15$ percent.





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