Structural Design & Detailing (RCC and Steel) MCQs for APSC PWD & WRD JE 2025: 2

Additional Structural Design & Detailing MCQs for APSC JE PWD & Water Resources 2025

Topics Covered

• RCC Design
• RCC Detailing
• Steel Design
• Steel Detailing
• Structural Analysis

Topic: RCC Design

41. What is the purpose of providing torsion reinforcement in RCC beams?

a) To resist bending moment b) To resist twisting forces c) To reduce beam depth d) To increase compressive strength

Answer: b) To resist twisting forces
Torsion reinforcement (stirrups and longitudinal bars) handles twisting as per IS 456.

Topic: RCC Design

42. What is the minimum grade of concrete for severe exposure conditions?

a) M20 b) M25 c) M30 d) M40

Answer: c) M30
IS 456 specifies M30 for severe exposure to ensure durability.

Topic: RCC Design

43. What is an over-reinforced RCC section?

a) Steel yields before concrete b) Concrete fails before steel yields c) Both fail simultaneously d) No reinforcement provided

Answer: b) Concrete fails before steel yields
Over-reinforced sections are brittle and avoided in design.

Topic: RCC Design

44. What is the partial safety factor for steel in LSM?

a) 1.15 b) 1.5 c) 1.0 d) 2.0

Answer: a) 1.15
IS 456 specifies 1.15 for steel in the Limit State Method.

Topic: RCC Design

45. Why is a T-beam used in RCC structures?

a) To reduce steel usage b) To utilize slab as compression flange c) To increase shear strength d) To improve aesthetics

Answer: b) To utilize slab as compression flange
T-beams increase moment capacity by using the slab in compression.

Topic: RCC Design

46. What is the maximum water-cement ratio for M25 concrete?

a) 0.40 b) 0.45 c) 0.50 d) 0.55

Answer: c) 0.50
IS 456 recommends a maximum of 0.50 for M25 under moderate exposure.

Topic: RCC Detailing

47. What is the minimum cover for RCC columns in moderate exposure?

a) 20 mm b) 25 mm c) 40 mm d) 50 mm

Answer: c) 40 mm
IS 456 specifies 40 mm for columns to protect against corrosion.

Topic: RCC Detailing

48. Why are distribution bars provided in RCC slabs?

a) To resist main bending moment b) To distribute loads and control cracking c) To increase slab thickness d) To reduce concrete strength

Answer: b) To distribute loads and control cracking
Distribution bars handle secondary stresses and shrinkage.

Topic: RCC Detailing

49. What is the maximum spacing of main bars in RCC slabs?

a) 150 mm b) 200 mm c) 300 mm d) 450 mm

Answer: c) 300 mm
IS 456 limits spacing to 3d or 300 mm, whichever is less.

Topic: RCC Detailing

50. What is the purpose of providing hooks in stirrups?

a) To increase shear capacity b) To ensure anchorage c) To reduce steel weight d) To improve concrete flow

Answer: b) To ensure anchorage
Hooks prevent stirrups from slipping under shear forces.

Topic: RCC Detailing

51. What is the minimum diameter of ties in RCC columns?

a) 6 mm b) 8 mm c) 10 mm d) 12 mm

Answer: b) 8 mm
IS 456 specifies 8 mm for column ties to confine concrete.

Topic: RCC Detailing

52. Why is development length important in RCC?

a) To reduce bar diameter b) To ensure full stress transfer c) To increase concrete volume d) To enhance durability

Answer: b) To ensure full stress transfer
Development length ensures the bar can transfer its full strength to concrete.

Topic: Steel Design

53. What is the purpose of a battened column?

a) To reduce column weight b) To increase buckling resistance c) To enhance fire resistance d) To improve aesthetics

Answer: b) To increase buckling resistance
Battens connect parallel members to act as one, per IS 800.

Topic: Steel Design

54. What is the yield strength of Fe 500 steel?

a) 415 MPa b) 500 MPa c) 550 MPa d) 600 MPa

Answer: b) 500 MPa
Fe 500 has a yield strength of 500 MPa as per IS standards.

Topic: Steel Design

55. What is the maximum slenderness ratio for a steel compression member?

a) 180 b) 200 c) 250 d) 300

Answer: a) 180
IS 800 limits compression members to a slenderness ratio of 180.

Topic: Steel Design

56. Why are rolled steel sections preferred in design?

a) High corrosion resistance b) Uniform properties and availability c) Low cost d) Fire resistance

Answer: b) Uniform properties and availability
Rolled sections like I-beams have consistent strength and are widely available.

Topic: Steel Design

57. What is a purlin in steel structures?

a) A vertical column b) A horizontal member supporting roof c) A foundation element d) A connection plate

Answer: b) A horizontal member supporting roof
Purlins support roof cladding and transfer loads to rafters.

Topic: Steel Design

58. What is the partial safety factor for steel in IS 800?

a) 1.0 b) 1.1 c) 1.5 d) 2.0

Answer: b) 1.1
IS 800 specifies 1.1 for steel in the Limit State Method.

Topic: Steel Detailing

59. What is the purpose of a base plate in steel columns?

a) To increase column height b) To transfer loads to foundation c) To reduce steel weight d) To enhance corrosion resistance

Answer: b) To transfer loads to foundation
Base plates distribute column loads to concrete footings.

Topic: Steel Detailing

60. What is the minimum pitch distance for bolts in steel?

a) 1.5 times bolt diameter b) 2.5 times bolt diameter c) 3.5 times bolt diameter d) 4 times bolt diameter

Answer: b) 2.5 times bolt diameter
IS 800 specifies 2.5d to ensure connection strength.

Topic: Steel Detailing

61. Why are fillet welds commonly used in steel connections?

a) High cost b) Ease of fabrication c) Low strength d) Fire resistance

Answer: b) Ease of fabrication
Fillet welds are simpler and faster to execute than groove welds.

Topic: Steel Detailing

62. What is the purpose of an angle section in steel detailing?

a) To reduce steel thickness b) To connect members or act as bracing c) To increase shear strength d) To improve durability

Answer: b) To connect members or act as bracing
Angles are versatile for connections and lateral stability.

Topic: Steel Detailing

63. What is the minimum size of a fillet weld as per IS 800?

a) 3 mm b) 5 mm c) 6 mm d) 8 mm

Answer: a) 3 mm
IS 800 specifies a minimum fillet weld size of 3 mm for structural welds.

Topic: Steel Detailing

64. What is a shop drawing in steel detailing?

a) A conceptual design sketch b) A detailed fabrication drawing c) A load calculation sheet d) A material testing report

Answer: b) A detailed fabrication drawing
Shop drawings guide the fabrication and erection of steel members.

Topic: Structural Analysis

65. What is the purpose of a shear force diagram?

a) To calculate deflections b) To determine shear stresses c) To measure concrete strength d) To analyze buckling

Answer: b) To determine shear stresses
Shear force diagrams show the variation of shear along a member.

Topic: Structural Analysis

66. What is a statically determinate structure?

a) Requires advanced analysis b) Can be solved using equilibrium equations c) Has redundant supports d) Fails under live loads

Answer: b) Can be solved using equilibrium equations
E.g., simply supported beams have no indeterminacy.

Topic: Structural Analysis

67. What is the slope-deflection method used for?

a) Shear force calculation b) Analysis of indeterminate structures c) Concrete mix design d) Steel weight estimation

Answer: b) Analysis of indeterminate structures
It calculates moments based on slopes and deflections.

Topic: Structural Analysis

68. What is a bending moment diagram used for?

a) To determine shear forces b) To analyze bending stresses c) To calculate deflections d) To measure steel strength

Answer: b) To analyze bending stresses
BMD shows the variation of moment along a member.

Topic: Structural Analysis

69. What is the degree of indeterminacy for a two-hinged arch?

a) 1 b) 2 c) 3 d) 4

Answer: a) 1
A two-hinged arch has one degree of indeterminacy.

Topic: Structural Analysis

70. What is the purpose of a flexibility matrix?

a) To calculate shear forces b) To analyze indeterminate structures c) To determine concrete strength d) To measure steel weight

Answer: b) To analyze indeterminate structures
The flexibility matrix relates displacements to forces in force methods.