rcc design beams slabs footings columns staircases retaining walls water tanks limit state and working stress methods - Question Bank

1. The minimum thickness of a water tank wall to resist hydrostatic pressure is determined by:
A) The grade of concrete
B) The grade of steel
C) The diameter of the tank and the head of water
D) The type of curing
2. The limiting moment of resistance of a singly reinforced rectangular beam depends on:
A) Grade of concrete and grade of steel only
B) Grade of concrete, grade of steel, and overall dimensions
C) Grade of concrete, grade of steel, and effective depth
D) Grade of concrete, grade of steel, and width of the beam
3. In a doubly reinforced beam, the additional compression reinforcement is provided when:
A) The beam is under shear stress
B) The required strength exceeds that of a singly reinforced beam
C) The deflection limits are exceeded
D) The bond stress is high
4. The depth of the foundation for a retaining wall is primarily determined by:
A) The height of the wall
B) The soil bearing capacity and the overturning moment
C) The amount of backfill
D) The type of soil
5. The minimum diameter of shear reinforcement (stirrups) in a beam is generally:
A) 6 mm
B) 8 mm
C) 10 mm
D) 12 mm
6. The load factor for dead load and live load in limit state design, according to IS 456:2000, is typically:
A) 1.5 for both
B) 1.5 for dead load, 1.5 for live load
C) 1.5 for dead load, 1.5 for live load (when acting together)
D) 1.0 for dead load, 1.5 for live load
7. The design of a footing is governed by:
A) Bending moment only
B) Shear force only
C) Punching shear and bending moment
D) Axial load only
8. For a slab supporting a heavy load and having a large span, the shear reinforcement is generally required when the average shear stress exceeds:
A) 0.5 N/mm²
B) 1.0 N/mm²
C) 1.5 N/mm²
D) 2.0 N/mm²
9. The critical section for shear in a beam, according to IS 456:2000, is at:
A) The center of the span
B) The face of the support
C) Half the effective depth from the support
D) One-third the effective depth from the support
10. In the working stress method, the stress distribution in concrete is assumed to be:
A) Parabolic
B) Rectangular
C) Triangular
D) Linear
11. The maximum percentage of steel reinforcement in a column is limited to:
A) 4%
B) 6%
C) 8%
D) 10%
12. The minimum grade of concrete for plain concrete footings is:
A) M10
B) M15
C) M20
D) M25
13. For a cantilever beam, the effective span is taken as:
A) Clear span plus half the width of the support
B) Clear span plus the depth of the beam
C) Clear span
D) Unsupported length
14. The lap length of reinforcement bars in tension is generally taken as:
A) 20 times the bar diameter
B) 24 times the bar diameter
C) 30 times the bar diameter
D) 40 times the bar diameter
15. The stress block parameters in limit state design for concrete are based on the:
A) Elastic theory
B) Plastic theory
C) Whitney's stress block
D) Rankine's theory
16. The main reinforcement in a one-way slab is provided along the:
A) Longer span
B) Shorter span
C) Both spans equally
D) Diagonal direction
17. In a retaining wall, the soil pressure acting on the backfill is:
A) Uniformly distributed
B) Triangularly distributed
C) Trapezoidal distribution
D) Parabolically distributed
18. The slenderness ratio of a column is the ratio of its effective length to its:
A) Unsupported length
B) Least lateral dimension
C) Overall length
D) Diameter
19. The minimum clear cover for main reinforcement in a reinforced concrete beam exposed to weather is:
A) 15 mm
B) 20 mm
C) 25 mm
D) 30 mm
20. In the limit state of collapse, the partial safety factor for loads is applied to:
A) Material strength
B) Service loads
C) Ultimate loads
D) Working stresses
21. The maximum amount of compression reinforcement in a beam, according to IS 456:2000, is:
A) 1% of the gross cross-sectional area
B) 2% of the gross cross-sectional area
C) 3% of the gross cross-sectional area
D) 4% of the gross cross-sectional area
22. The bond stress in plain bars is generally:
A) Higher than in deformed bars
B) Lower than in deformed bars
C) Equal to that in deformed bars
D) Negligible
23. In the design of staircases, the tread is the horizontal part and the riser is the:
A) Inclined part
B) Supporting beam
C) Vertical part
D) Landing
24. The effective length of a column is the product of its unsupported length and a factor that depends on:
A) The cross-sectional dimensions of the column
B) The end conditions of the column
C) The grade of concrete used
D) The amount of shear reinforcement
25. The limiting depth of the neutral axis for a singly reinforced rectangular beam in Fe 415 steel is approximately:
A) 0.46 d
B) 0.53 d
C) 0.63 d
D) 0.73 d
26. For a two-way slab simply supported on all four sides, the ratio of the longer span to the shorter span, beyond which it is considered a one-way slab, is:
A) 1.0
B) 1.5
C) 2.0
D) 2.5
27. The minimum percentage of tension reinforcement in a singly reinforced rectangular beam is:
A) 0.85 / fy
B) 0.5 / fy
C) 1.0 / fy
D) 2.0 / fy
28. The maximum spacing of shear reinforcement (stirrups) in a beam, according to IS 456:2000, is the least of:
A) Effective depth, 300 mm, or 3 times the web thickness
B) Effective depth, 400 mm, or 3 times the web thickness
C) Effective depth, 300 mm, or 4 times the web thickness
D) Effective depth, 400 mm, or 4 times the web thickness
29. In the working stress method, the stress in concrete at the extreme fiber is limited to:
A) 0.45 fck
B) 0.67 fck
C) 0.87 fy
D) 0.002
30. For water tanks, the concrete mix should be:
A) Lean mix
B) Rich mix
C) Nominal mix
D) Standard mix
31. The modular ratio 'm' is defined as the ratio of the modulus of elasticity of steel to the modulus of elasticity of concrete, i.e., m = Es / Ec. Its value is approximately:
A) 7
B) 10
C) 15
D) 20
32. The function of transverse reinforcement (stirrups) in a beam is to resist:
A) Bending moment
B) Shear force
C) Torsional moment
D) Axial load
33. The minimum diameter of longitudinal reinforcing bars in a column is:
A) 8 mm
B) 10 mm
C) 12 mm
D) 16 mm
34. In the limit state of serviceability, the deflection is checked for:
A) Maximum load
B) Factored load
C) Characteristic load
D) Ultimate load
35. The effective width of a flange for a continuous T-beam is taken as:
A) Span/6 + width of web + 6 * thickness of flange
B) Span/12 + width of web + 3 * thickness of flange
C) Span/8 + width of web + 4 * thickness of flange
D) Span/10 + width of web + 5 * thickness of flange
36. A T-beam is considered as a rectangular beam when the neutral axis is located:
A) Within the flange
B) Below the flange
C) At the junction of flange and web
D) Above the flange
37. The development length of a bar is the length of embedment required to develop the:
A) Compressive strength of the bar
B) Tensile strength of the bar
C) Bond strength between the bar and concrete
D) Yield strength of the bar
38. For a column subjected to axial load and bending, the stress distribution is assumed to be:
A) Uniform
B) Linear
C) Parabolic
D) Rectangular
39. The minimum reinforcement in a slab is provided to:
A) Reduce deflection
B) Prevent cracking due to temperature and shrinkage
C) Increase shear strength
D) Improve ductility
40. In the limit state of collapse, the design load is obtained by multiplying the service load by a:
A) Serviceability factor
B) Material factor
C) Load factor
D) Factor of safety
41. The shear strength of concrete is primarily dependent on:
A) Tensile strength of concrete
B) Compressive strength of concrete
C) Modulus of elasticity of concrete
D) Poisson's ratio of concrete
42. For footing design, the maximum bending moment is usually calculated at the:
A) Center of the column face
B) Edge of the column
C) Center of the footing
D) Projection of the footing
43. The limiting deflection for a simply supported beam, as per IS 456:2000, is generally taken as a fraction of the span. The common fraction is:
A) 1/150
B) 1/250
C) 1/350
D) 1/500
44. In the working stress method, the stress distribution in concrete and steel at the ultimate load is assumed to be:
A) Parabolic in concrete and linear in steel
B) Rectangular in concrete and linear in steel
C) Triangular in concrete and linear in steel
D) Linear in both concrete and steel
45. For a rectangular column, the minimum eccentricity is taken as:
A) Length/500 + lateral dimension/30
B) Length/100 + lateral dimension/20
C) Length/20 + lateral dimension/10
D) Length/50 + lateral dimension/5
46. The minimum grade of concrete for reinforced concrete work exposed to moderate conditions as per IS 456:2000 is:
A) M15
B) M20
C) M25
D) M30
47. According to IS 456:2000, the maximum diameter of reinforcing bars that can be used in a one-way slab without shear reinforcement is:
A) 8 mm
B) 10 mm
C) 12 mm
D) 16 mm
48. The effective span of a simply supported beam is taken as:
A) Clear span plus the depth of the beam
B) Clear span plus half the width of the support
C) Clear span minus the width of the support
D) Clear span
49. In limit state design of reinforced concrete, the limit state of collapse corresponds to:
A) Unacceptable durability
B) Excessive deflection
C) Rupture of the structure
D) Cracking of concrete