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

30 Structural Design & Detailing (RCC and Steel) MCQs for APSC JE PWD & Water Resources 2025

Topics Covered

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

Topic: RCC Design

1. What is the primary purpose of reinforcement in RCC?

a) Increase compressive strength b) Resist tensile forces c) Reduce concrete volume d) Improve insulation

Answer: b) Resist tensile forces
Steel reinforcement compensates for concrete’s low tensile strength.

Topic: RCC Design

2. Which method is commonly used for RCC design in India?

a) Working Stress Method b) Limit State Method c) Ultimate Load Method d) Elastic Method

Answer: b) Limit State Method
It ensures safety and serviceability as per IS 456:2000.

Topic: RCC Design

3. What is the minimum grade of concrete for RCC as per IS 456?

a) M10 b) M15 c) M20 d) M25

Answer: c) M20
M20 is the minimum grade for RCC to ensure adequate strength.

Topic: RCC Detailing

4. What is the purpose of providing stirrups in beams?

a) Increase compressive strength b) Resist shear forces c) Reduce beam depth d) Enhance durability

Answer: b) Resist shear forces
Stirrups prevent shear failure in RCC beams.

Topic: RCC Detailing

5. What is the minimum cover for RCC slabs exposed to weather?

a) 15 mm b) 20 mm c) 25 mm d) 40 mm

Answer: c) 25 mm
IS 456 specifies 25 mm cover for slabs to protect reinforcement from corrosion.

Topic: RCC Detailing

6. Why is anchorage length provided in RCC?

a) To reduce steel usage b) To ensure bond strength c) To increase beam width d) To improve aesthetics

Answer: b) To ensure bond strength
Anchorage length transfers forces between steel and concrete.

Topic: Structural Analysis

7. What is the primary load considered in RCC design?

a) Dead load b) Live load c) Wind load d) Earthquake load

Answer: a) Dead load
Dead load (self-weight) is a constant primary load in design.

Topic: RCC Design

8. What is the maximum span-to-depth ratio for a simply supported RCC beam?

a) 10 b) 20 c) 26 d) 32

Answer: b) 20
IS 456 recommends a span/depth ratio of 20 for simply supported beams.

Topic: RCC Detailing

9. What is the purpose of a curtailment of bars in beams?

a) Increase shear resistance b) Reduce steel quantity c) Improve concrete strength d) Enhance durability

Answer: b) Reduce steel quantity
Curtailment stops bars where bending moment decreases, optimizing steel use.

Topic: RCC Design

10. What is the characteristic strength of concrete?

a) Average strength b) Strength below which 5% of results fall c) Maximum strength d) Strength after 7 days

Answer: b) Strength below which 5% of results fall
It’s a statistical measure for design as per IS 456.

Topic: RCC Detailing

11. What is the minimum diameter of bars for main reinforcement in slabs?

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

Answer: b) 8 mm
IS 456 specifies 8 mm as the minimum for main bars in slabs.

Topic: Structural Analysis

12. What is the factor of safety in the Limit State Method?

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

Answer: c) 1.5
A partial safety factor of 1.5 is applied to concrete in LSM.

Topic: RCC Design

13. What is the purpose of a doubly reinforced beam?

a) Reduce beam depth b) Resist both tension and compression c) Increase shear strength d) Improve aesthetics

Answer: b) Resist both tension and compression
Top and bottom steel handle high moments.

Topic: RCC Detailing

14. What is the maximum spacing of stirrups in beams?

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

Answer: c) 300 mm
IS 456 limits stirrup spacing to 300 mm or 0.75d, whichever is less.

Topic: Structural Analysis

15. What is a moment distribution method used for?

a) Shear force calculation b) Analysis of indeterminate structures c) Deflection measurement d) Concrete mix design

Answer: b) Analysis of indeterminate structures
It balances moments in continuous beams and frames.

Topic: Steel Design

16. What is the primary advantage of steel structures?

a) Low cost b) High tensile strength c) Fire resistance d) Corrosion resistance

Answer: b) High tensile strength
Steel excels in tension, making it ideal for long spans.

Topic: Steel Design

17. Which code governs steel design in India?

a) IS 456 b) IS 800 c) IS 875 d) IS 1893

Answer: b) IS 800
IS 800:2007 provides guidelines for steel structure design.

Topic: Steel Design

18. What is the yield strength of Fe 415 steel?

a) 250 MPa b) 415 MPa c) 500 MPa d) 600 MPa

Answer: b) 415 MPa
Fe 415 indicates a yield strength of 415 MPa.

Topic: Steel Detailing

19. What is the purpose of a gusset plate?

a) Increase beam depth b) Connect steel members c) Reduce steel weight d) Improve insulation

Answer: b) Connect steel members
Gusset plates join beams, columns, or truss members.

Topic: Steel Detailing

20. What is the minimum bolt diameter for structural connections?

a) 10 mm b) 12 mm c) 16 mm d) 20 mm

Answer: c) 16 mm
IS 800 recommends 16 mm as the minimum for structural bolts.

Topic: Steel Design

21. What is a tension member in steel design?

a) Member under compression b) Member under tensile force c) Member under shear d) Member under bending

Answer: b) Member under tensile force
E.g., tie rods or cables resist pulling forces.

Topic: Steel Detailing

22. What is the purpose of stiffeners in steel beams?

a) Reduce beam weight b) Prevent web buckling c) Increase shear strength d) Enhance corrosion resistance

Answer: b) Prevent web buckling
Stiffeners stabilize the web under load.

Topic: Steel Design

23. What is the slenderness ratio in steel design?

a) Ratio of length to width b) Ratio of effective length to radius of gyration c) Ratio of depth to thickness d) Ratio of span to depth

Answer: b) Ratio of effective length to radius of gyration
It determines buckling capacity of compression members.

Topic: Steel Detailing

24. What is the minimum edge distance for bolts in steel?

a) 1.5 times bolt diameter b) 2 times bolt diameter c) 2.5 times bolt diameter d) 3 times bolt diameter

Answer: a) 1.5 times bolt diameter
IS 800 specifies this to prevent edge failure.

Topic: Structural Analysis

25. What is a plastic hinge in steel structures?

a) A rigid joint b) A point of yielding under bending c) A shear failure point d) A connection detail

Answer: b) A point of yielding under bending
It allows rotation in plastic analysis.

Topic: Steel Design

26. What is the purpose of a plate girder?

a) Reduce steel weight b) Support heavy loads over long spans c) Increase corrosion resistance d) Improve aesthetics

Answer: b) Support heavy loads over long spans
Plate girders are used in bridges and large buildings.

Topic: Steel Detailing

27. What is the advantage of welded connections over bolted?

a) Lower cost b) Greater rigidity c) Easier inspection d) Faster installation

Answer: b) Greater rigidity
Welded joints provide a stiffer connection.

Topic: Steel Design

28. What is a compression member in steel design?

a) Member under tension b) Member under compressive force c) Member under shear d) Member under torsion

Answer: b) Member under compressive force
E.g., columns resist axial compression.

Topic: Steel Detailing

29. What is the purpose of a cleat in steel connections?

a) Reduce steel thickness b) Support beams on columns c) Increase shear strength d) Enhance durability

Answer: b) Support beams on columns
Cleats provide a simple connection for beam ends.

Topic: Structural Analysis

30. What is the influence line used for?

a) Concrete mix design b) Analyzing moving loads c) Measuring deflection d) Calculating steel weight

Answer: b) Analyzing moving loads
It determines maximum effects of live loads on structures.