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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