Home / Civil Engineering / RCC Structures Design :: Section 1

### Civil Engineering :: RCC Structures Design

1.  In a combined footing if shear stress exceeds 5 kg/cm2, the nominal stirrups provided are:
2.  A. 6 legged B. 8 legged C. 10 legged D. 12 legged E. none of these.

3.  The maximum area of tension reinforcement in beams shall not exceed
4. A.
 0.15%
B.

1.5%

C.

4%

D.

1%

5.  As per I.S. 456 - 1978, the pH value of water shall be
6. A.

less than 6

B.

equal to 6

C.
 not less than 6
D.
 equal to 7

7. The minimum number of main steel bars provided in R.C.C.

8.  A. rectangular columns is 4 B. circular columns is 6 C. octagonal columns is 8 D. all the above.

9. Post tensioning system

10.  A. was widely used in earlier days B. is not economical and hence not generally used C. is economical for large spans and is adopted now a days D. none of these.

11.  An R.C.C. column is treated as long if its slenderness ratio is greater than
12. A.
 30
B.

35

C.

40

D.

50

E.

60

13.  The width of the flange of a T-beam should be less than
14. A.

one-third of the effective span of the T-beam

B.

distance between the centres of T-beam

C.
 breadth of the rib plus twelve times the thickness of the slab
D.

least of the above.

15. A prestressed rectangular beam which carries two concentrated loads W at L/3 from either end, is provided with a bent tendon with tension P such that central one-third portion of the tendon remains parallel to the longitudinal axis, the maximum dip h is

16.  A. $$\frac { WL } { P}$$ B. $$\frac { WL } {2 P}$$ C. $$\frac { WL } {3 P}$$ D. $$\frac { WL } {4 P}$$

17.  Pick up the correct statement from the following:
18. A.
 A pile is a slender member which transfers the load through its lower end on a strong strata
B.

A pile is a slender member which transfers its load to the surrounding soil

C.

A pile is a slender member which transfers its load by friction

D.

A pile is a cylindrical body of concrete which transfers the load at a depth greater than its width.

19.  . Cantilever retaining walls can safely be used for a height not more than
20. A.
 3 m
B.
 4 m
C.
 5 m
D.
 6 m
E.
 8 m

21.  If W is the load on a circular slab of radius R, the maximum circumferential moment at the centre of the slab, is
22.  A. $$\frac { WR^2 } {16 }$$ B. $$\frac { 2WR^2 } {16 }$$ C. $$\frac { 3WR^2 } {16 }$$ D. zero E. none of these.

23.  If a bent tendon is required to balance a concentrated load W at the centre of the span L, the central dip h must be at least
24.  A. $$\frac { WL } { P }$$ B. $$\frac { WL } { 2P }$$ C. $$\frac { WL } {3 P }$$ D. $$\frac { WL } { 4P }$$ E. $$\frac { 3WL } { 5P }$$

25. For M 150 mix concrete, according to I.S. specifications, local bond stress, is

26. A.

5 kg/cm2

B.

10 kg/cm2

C.

15 kg/cm2

D.
 20 kg/cm2
E.
 25 kg/cm2

27.  If the average bending stress is 6 kg/cm2 for M 150 grade concrete, the length of embedment of a bar of diameter d according to I.S. 456 specifications, is
28. A.
 28 d
B.

38 d

C.

48 d

D.
 58 d
E.
 95 d

29.  Bottom bars under the columns are extended into the interior of the footing slab to a distance greater than
30.  A. 42 diameters from the centre of the column B. 42 diameters from the inner edge of the column C. 42 diameters from the outer edge of the column D. 24 diameter from the centre of the column

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

32. A.

6 mm

B.

8 mm

C.

10 mm

D.
 12 mm
E.

none of these.

33.  The design of a retaining wall assumes that the retained earth
34. A.
 is dry
B.

is free from moisture

C.

is not cohesives

D.

consists of granular particles

E.

all the above.

35.  Dimensions of a beam need be changed if the shear stress is more than
36. A.

10 kg/cm2

B.

15 kg/cm2

C.

20 kg/cm2

D.
 25 kg/cm2

37. The thickness of base slab of a retaining wall generally provided, is

38.  A. one half of the width of the stem at the bottom B. one-third of the width of the stem at the bottom C. one fourth of the width of the steam at the bottom D. width of the stem at the bottom E. twice the width of the steam at the bottom.

39. For a circular slab carrying a uniformly distributed load, the ratio of the maximum negative to maximum positive radial moment, is

40.  A. 1 B. 2 C. 3 D. 4 E. 5

41.  Thickened part of a flat slab over its supporting column, is technically known as
42. A.
 drop panel
B.

capital

C.

D.

none of these.

43.  An R.C.C. beam not provided with shear reinforcement may develop cracks in its bottom inclined roughly to the horizontal at
44. A.

25°

B.
 35°
C.
 45°
D.
 55°
E.
 60°

45.  The effective span of a simply supported slab, is
46.  A. distance between the centres of the bearings 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.

47.  Pick up the incorrect statement from the following:
48. A.

In the stem of a retaining wall, reinforcement is provided near the earth side

B.
 In the toe slab of a retaining wall, rein forcement is provided at the bottom of the slab
C.

In the heel slab of a retaining wall, rein forcement is provided at the top of the slab

D.

None of these.

49.  . The minimum cube strength of concrete used for a prestressed member, is
50.  A. 50 kg/cm2 B. 150 kg/cm2 C. 250 kg/cm2 D. 350 kg/cm2 E. 400 kg/cm2

51.  The number of treads in a flight is equal to
52. A.

risers in the flight

B.
 risers plus one
C.
 risers minus one
D.
 none of these.

53.  A short column 20 cm x 20 cm in section is reinforced with 4 bars whose area of cross section is 20 sq. cm. If permissible compressive stresses in concrete and steel are 40 kg/cm2 and 300 kg/cm2, the Safe load on the column, should not exceed
54. A.
 4120 kg
B.

41, 200 kg

C.

412, 000 kg

D.
 none of these.

55.  The reinforced concrete beam which has width 25 cm, lever arm 40 cm, shear force 6t/cm2, safe shear stress 5 kg/cm2 and B.M. 24 mt,
56. A.
 is safe in shear
B.
 is unsafe in shear
C.

is over safe in shear

D.

needs redesigning.

57.  In a beam the local bond stress Sb, is equal to
58.  A. $$\frac { \text{shear fore} } { \text{Lever arm *Total perimeter of reinforcement} }$$ B. $$\frac { \text{Total perimeter of reinforcement} } { \text{Lever am*shear force} }$$ C. $$\frac { \text{Lever arm}} { \text{shear force*Total perimeter of reinforcement}}$$ D. $$\frac { \text{Lever arm} } { \text{Bendimg moment 8Total perimeter} }$$

59.  According to I.S. : 456 specifications, the safe diagonal tensile stress for M 150 grade concrete, is
60. A.

5 kg/cm2

B.

10 kg/cm2

C.
 15 kg/cm2
D.
 20 kg/cm2
E.

25 kg/cm2

61.  A foundation rests on
62. A.

base of the foundation

B.

C.
 foundation soil
D.

both (b) and (c)

63.  For initial estimate for a beam design, the width is assumed
64. A.

1/15th of span

B.
 1/20th of span
C.

1/25th of span

D.
 1/30th of span
E.

1/40th of span.

65.  If R and T are rise and tread of a stair spanning horizontally, the steps are supported by a wall on one side and by a stringer beam on the other side, the steps are designed as beams of width
66. A.

R + T

B.
 T-R
C.

$$\sqrt{R^2+T^2}$$

D.

R - T

67.  The advantage of a concrete pile over a timber pile, is
68. A.

no decay due to termites

B.
 no restriction on length
C.

higher bearing capacity

D.

not necessary to cut below the water mark

E.

all the above.

69.  If the permissible compressive stress for a concrete in bending is C kg/m2, the modular ratio is
70. A.
 2800/C
B.
 2300/2C
C.

2800/3C

D.

2800/C2

71.  If d and n are the effective depth and depth of the neutral axis respectively of a singly reinforced beam, the lever arm of the beam, is
72.  A. d B.  n C. d + $$\frac { n} {3}$$ D. d - $$\frac { n} {3}$$ E. d - $$\frac { n} {3}$$

73.  To have pressure wholly compressive under the base of a retaining wall of width b, the resultant of the weight of the wall and the pressure exerted by the retained, earth should have eccentricity not more than
74.  A. $$\frac { b} { 3 }$$ B. $$\frac { b} { 4 }$$ C. $$\frac { b} { 5 }$$ D. $$\frac { b} { 6 }$$ E. $$\frac { b} { 8}$$

75.  The width of the flange of a T-beam, which may be considered to act effectively with the rib depends upon
76. A.
B.

overall thickness of the rib

C.

centre to centre distance between T-beams

D.
 span of the T-beam
E.

all the above.

77. Design of a two way slab simply supported on edges and having no provision to prevent the corners from lifting, is made by

78.  A. Rankine formula B. Marcus formula C. Rankine Grashoff formula D. Grashoff formula E. Rankine-Marcus formula.

79. Design of R.C.C. simply supported beams carrying U.D.L. is based on the resultant B.M. at

80.  A. supports B. mid span C. every section D. quarter span.

81.  The transverse reinforcements provided at right angles to the main reinforcement
82. A.
B.

resist the temperature stresses

C.

resist the shrinkage stress

D.

all the above.

83.  The amount of reinformcement for main bars in a slab, is based upon
84. A.

minimum bending moment

B.
 maximum bending moment
C.

maximum shear force

D.

minimum shear force.

85.  If the effective length of a 32 cm diameter R.C.C. column is 4.40 m, its slenderness ratio, is
86. A.
 40
B.

45

C.

50

D.

55

E.

60

87. The percentage of minimum reinforcement of the gross sectional area in slabs, is

88.  A. 0.10% B. 0.12% C. 0.15% D. 0.18% E. 0.20%

89. A continuous beam shall be deemed to be a deep beam if the ratio of effective span to overall depth, is

90.  A. 2.5 B. 2.0 C. less than 2 D. less than 2.5

91.  If T and R are tread and rise respectively of a stair, then
92.  A. 2R + T = 60 B. R + 2T = 60 C. 2R + T = 30 D. R + 2T= 30 E. 3R + 27 = 30

93.  If k is wobble correction factor, Î¼ is coefficient of friction between the duct surface and the curve of tendon of radius R, the tension ratio at a distance x from either end, is
94.  A. 1 + KX - $$\frac { \mu X } { R }$$ B. 1 - kX + $$\frac { \mu X } { R }$$ C. 1 - kX - $$\frac { \mu X } { R }$$ D. 1 + KX +$$\frac { \mu X } { R }$$ E. 1+$$\frac { K } { R}$$- $$\frac { \mu X } { R }$$

95.  In a prestressed beam carrying an external load W with a bent tendon is having angle of inclination Î¸ and prestressed load P. The net downward load at the centre is
96. A.

W - 2P cos θ

B.

W - P cos θ

C.

W - P sin θ

D.

W - 2P sin θ

E.
 W + 2P sin θ

97. The effective width of a column strip of a flat slab, is

98. A.

one-fourth the width of the panel

B.
 half the width of the panel
C.

D.

diameter of the column

E.

none of these.

99. High strength concrete is used in prestressed member

100. A.
 to overcome high bearing stresses developed at the ends
B.

to ovecome bursting stresses at the ends

C.

to provide high bond stresses

D.

to overcome cracks due to shrinkage

E.

all the above.